Autor(es) | Título | Ano | Periódico | Tipo | DOI/URL |
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Zuquim, G., Tuomisto, H., Jones, M.M., Prado, J., Figueiredo, F.O., Moulatlet, G., Costa, F.R., Quesada, C. and Emilio, T. | Predicting environmental gradients with fern species composition in Brazilian Amazonia [BibTeX] |
2014 | Journal of Vegetation Science Vol. 8, pp. n/a-n/a |
article | |
BibTeX:
@article{zuquim_predicting_2014, author = {Zuquim, G. and Tuomisto, H. and Jones, M. M. and Prado, J. and Figueiredo, F. O.G. and Moulatlet, G.M. and Costa, F. R.C. and Quesada, C.A. and Emilio, T.}, title = {Predicting environmental gradients with fern species composition in Brazilian Amazonia}, journal = {Journal of Vegetation Science}, year = {2014}, volume = {8}, pages = {n/a--n/a} } |
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Zimmermann, M., Meir, P., Silman, M.R., Fedders, A., Gibbon, A., Malhi, Y., Urrego, D.H., Bush, M.B., Feeley, K.J., Garcia, K.C., Dargie, G.C., Farfan, W.R., Goetz, B.P., Johnson, W.T., Kline, K.M., Modi, A.T., Rurau, N.M.Q., Staudt, B.T. and Zamora, F. | No Differences in Soil Carbon Stocks Across the Tree Line in the Peruvian Andes | 2010 | Ecosystems Vol. 13(1), pp. 62-74 |
article | DOI |
Abstract: Reliable soil organic carbon (SOC) stock measurements of all major ecosystems are essential for predicting the influence of global warming on global soil carbon pools, but hardly any detailed soil survey data are available for tropical montane cloud forests (TMCF) and adjacent high elevation grasslands above (puna). TMCF are among the most threatened of ecosystems under current predicted global warming scenarios. We conducted an intensive soil sampling campaign extending 40 km along the tree line in the Peruvian Andes between 2994 and 3860 m asl to quantify SOC stocks of TMCF, puna grassland, and shrubland sites in the transition zone between the two habitats. SOC stocks from the soil surface down to the bedrock averaged (+/- standard error SE) 11.8 (+/- 1.5, N = 24) kg C/m(2) in TMCF, 14.7 (+/- 1.4, N = 9) kg C/m(2) in the shrublands and 11.9 (+/- 0.8, N = 35) kg C/m(2) in the grasslands and were not significantly different (P textgreater 0.05 for all comparisons). However, soil profile analysis revealed distinct differences, with TMCF profiles showing a uniform SOC distribution with depth, shrublands a linear decrease, and puna sites an exponential decrease in SOC densities with soil depth. Organic soil layer thickness reached a maximum (similar to 70 cm) at the upper limit of the TMCF and declined with increasing altitude toward puna sites. Within TMCF, no significant increase in SOC stocks with increasing altitude was observed, probably because of the large variations among SOC stocks at different sites, which in turn were correlated with spatial variation in soil depth. | |||||
BibTeX:
@article{zimmermann_no_2010, author = {Zimmermann, Michael and Meir, Patrick and Silman, Miles R. and Fedders, Anna and Gibbon, Adam and Malhi, Yadvinder and Urrego, Dunia H. and Bush, Mark B. and Feeley, Kenneth J. and Garcia, Karina C. and Dargie, Greta C. and Farfan, Wiliam R. and Goetz, Bradley P. and Johnson, Wesley T. and Kline, Krystle M. and Modi, Andrew T. and Rurau, Natividad M. Q. and Staudt, Brian T. and Zamora, Flor}, title = {No Differences in Soil Carbon Stocks Across the Tree Line in the Peruvian Andes}, journal = {Ecosystems}, year = {2010}, volume = {13}, number = {1}, pages = {62--74}, url = {://WOS:000275172700004}, doi = {https://doi.org/10.1007/s10021-009-9300-2} } |
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Zimmermann, A., Germer, S., Neill, C., Krusche, A.V. and Elsenbeer, H. | Spatio-temporal patterns of throughfall and solute deposition in an open tropical rain forest | 2008 | Journal of Hydrology Vol. 360(1-4), pp. 87-102 |
article | DOI |
Abstract: The brief interaction of precipitation with a forest canopy can create a high spatial variability of both throughfall and solute deposition. We hypothesized that (i) the variability in natural forest systems is high but depends on system-inherent stability, (ii) the spatial variability of solute deposition shows seasonal dynamics depending on the increase in rainfall frequency, and (iii) spatial patterns persist only in the short-term. The study area in the north-western Brazilian state of Rondonia is subject to a climate with a distinct wet and dry season. We collected rain and throughfall on an event basis during the early wet season (n = 14) and peak of the wet season (n = 14) and analyzed the samples for pH and concentrations of NH4+, Na+, K+, Ca2+ Mg2+,, Cl-, NO3-, SO42- and DOC. The coefficient 3 4 cient of variation for throughfall based on both sampling intervals was 29%, which is at the lower end of values reported from other tropical forest sites, but which is higher than in most temperate forests. Coefficients of variation of solute deposition ranged from 29% to 52%. This heterogeneity of solute deposition is neither particularly high nor particularly tow compared with a range of tropical and temperate forest ecosystems. We observed an increase in solute deposition variability with the progressing wet season, which was explained by a negative correlation between heterogeneity of solute deposition and antecedent dry period. The temporal stability of throughfall. patterns was Low during the early wet season, but gained in stability as the wet season progressed. We suggest that rapid plant growth at the beginning of the rainy season is responsible for the lower stability, whereas less vegetative activity during the later rainy season might favor the higher persistence of "hot" and "cold" spots of throughfall. quantities. The relatively high stability of throughfall patterns during later stages of the wet season may influence processes at the forest floor and in the soil. Solute deposition patterns showed less clear trends but all patterns displayed a short-term stability only. The weak stability of those patterns is apt to impede the formation of solute deposition -induced biochemical microhabitats in the soil. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{zimmermann_spatio-temporal_2008, author = {Zimmermann, Alexander and Germer, Sonja and Neill, Christopher and Krusche, Alex V. and Elsenbeer, Helmut}, title = {Spatio-temporal patterns of throughfall and solute deposition in an open tropical rain forest}, journal = {Journal of Hydrology}, year = {2008}, volume = {360}, number = {1-4}, pages = {87--102}, url = {://WOS:000259793700007}, doi = {https://doi.org/10.1016/j.jhydrol.2008.07.028} } |
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Zhuang, Y., Fu, R., Marengo, J.A. and Wang, H. | Seasonal variation of shallow-to-deep convection transitionand its link to the environmental conditions over the Central Amazon [BibTeX] |
2017 | J. Geophys. Res. Atmos. Vol. 122 |
article | DOI |
BibTeX:
@article{zhuang_seasonal_2017, author = {Zhuang, Y. and Fu, R. and Marengo, J. A. and Wang, H.}, title = {Seasonal variation of shallow-to-deep convection transitionand its link to the environmental conditions over the Central Amazon}, journal = {J. Geophys. Res. Atmos.}, year = {2017}, volume = {122}, doi = {https://doi.org/10.1002/2016JD025993} } |
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Zhou, J.C., Swietlicki, E., Hansson, H.C. and Artaxo, P. | Submicrometer aerosol particle size distribution and hygroscopic growth measured in the Amazon rain forest during the wet season | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20), pp. 8055- 8065 |
article | DOI URL |
Abstract: The number-size distribution and hygroscopic growth of submicrometer aerosol particles were measured in central Amazonia during the first Cooperative LBA Airborne Regional Experiment (CLAIRE) wet season experiment in March-April 1998. This was the first time ever that these types of measurements were performed in the Amazon rain forest. A Differential Mobility Particle Sizer (DMPS) was used to measure aerosol number-size distribution with diameters in the range 3-850 nm. The observed total number concentrations were frequently between 300 and 600 cm(-3) with a mean value around 450 cm(-3). Two aerosol particle modes (Aitken and accumulation mode) were always present. The average particle concentrations for those two modes were 239 and 177 cm(-3), with geometric diameters of 68 and 151 nm, respectively. An ultrafine mode had a number concentration and a mean diameter of 92 cm(-3) and 24 nm, respectively, and only occurred at 18% of the time, causing the size distribution to be trimodal instead of bimodal. The hygroscopic growth of aerosol particles was measured in situ with a Hygroscopic Tandem Differential Mobility Analyzer (H-TDMA) at six dry particle diameters between 35 and 265 nm. In contrast to the bimodal hygroscopic behavior found in polluted continental environments, the hygroscopic properties of aerosol particles in the Amazon rain forest is essentially unimodal with average diameter growth factors of 1.16-1.32 from dry to 90% relative humidity (RH). Aerosol soluble volume fractions were, in general, between 0.14 and 0.27, estimated by assuming that only ammonium hydrogen sulphate interacted with water vapour. | |||||
BibTeX:
@article{zhou_submicrometer_2002, author = {Zhou, J. C. and Swietlicki, E. and Hansson, H. C. and Artaxo, P.}, title = {Submicrometer aerosol particle size distribution and hygroscopic growth measured in the Amazon rain forest during the wet season}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, pages = {8055-- 8065}, url = {://WOS:000180466200012}, doi = {https://doi.org/10.1029/2000jd000203} } |
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Zheng, R. and Y., D. | Linear relation between convective cloud base height and updrafts and application to satellite retrievals [BibTeX] |
2015 | Geophysical Research Letters Vol. 42, pp. 6485-6491 |
article | DOI |
BibTeX:
@article{zheng_linear_2015, author = {Zheng, Rosenfeld, D., Y.}, title = {Linear relation between convective cloud base height and updrafts and application to satellite retrievals}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, pages = {6485--6491}, doi = {https://doi.org/10.1002/2015GL064809} } |
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Zhang, Y., Sanchez, M.S., Douet, C. and al. , e. | Changing shapes and implied viscosities of suspended submicron particles [BibTeX] |
2015 | Atmospheric Chemistry and Physics Vol. 15(14), pp. 7819-7829 |
article | DOI |
BibTeX:
@article{zhang_changing_2015, author = {Zhang, Y. and Sanchez, M. S and Douet, C. and al., et}, title = {Changing shapes and implied viscosities of suspended submicron particles}, journal = {Atmospheric Chemistry and Physics}, year = {2015}, volume = {15}, number = {14}, pages = {7819--7829}, doi = {https://doi.org/10.5194/acp-15-7819-2015} } |
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Zhang, Y., Fu, R., Yu, H., Qian, Y., Dickinson, R., Silva Dias, M.A.F., da Silva Dias, P.L. and Fernandes, K. | Impact of biomass burning aerosol on the monsoon circulation transition over Amazonia | 2009 | Geophysical Research Letters Vol. 36 |
article | DOI URL |
Abstract: Ensemble simulations of a regional climate model (RegCM3) forced by aerosol radiative forcing suggest that biomass burning aerosols can work against the seasonal monsoon circulation transition, thus re-enforce the dry season rainfall pattern for Southern Amazonia. Strongly absorbing smoke aerosols warm and stabilize the lower troposphere within the smoke center in southern Amazonia (where aerosol optical depth textgreater0.3). These changes increase the surface pressure in the smoke center, weaken the southward surface pressure gradient between northern and southern Amazonia, and consequently induce an anomalous moisture divergence in the smoke center and an anomalous convergence in northwestern Amazonia (5 degrees S-5 degrees N, 60 degrees W-70 degrees W). The increased atmospheric thermodynamic stability, surface pressure, and divergent flow in Southern Amazonia may inhibit synoptic cyclonic activities propagated from extratropical South America, and re-enforce winter-like synoptic cyclonic activities and rainfall in southeastern Brazil, Paraguay and northeastern Argentina. Citation: Zhang, Y., R. Fu, H. Yu, Y. Qian, R. Dickinson, M. A. F. Silva Dias, P. L. da Silva Dias, and K. Fernandes (2009), Impact of biomass burning aerosol on the monsoon circulation transition over Amazonia, Geophys. Res. Lett., 36, L10814, doi: 10.1029/2009GL037180. | |||||
BibTeX:
@article{zhang_impact_2009, author = {Zhang, Yan and Fu, Rong and Yu, Hongbin and Qian, Yun and Dickinson, Robert and Silva Dias, Maria Assuncao F. and da Silva Dias, Pedro L. and Fernandes, Katia}, title = {Impact of biomass burning aerosol on the monsoon circulation transition over Amazonia}, journal = {Geophysical Research Letters}, year = {2009}, volume = {36}, url = {://WOS:000266518400001}, doi = {https://doi.org/10.1029/2009gl037180} } |
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Zhan, X.W., Xue, Y.K. and Collatz, G.J. | An analytical approach for estimating CO2 and heat fluxes over the Amazonian region | 2003 | Ecological Modelling Vol. 162(1-2), pp. 97-117 |
article | DOI URL |
Abstract: Accurate assessments of the CO2 fluxes between the terrestrial ecosystems and the atmosphere are pressingly needed for the climate change and carbon cycle studies. The Collatz et al. parameterization of leaf photosynthesis-stomatal conductance has been widely applied in land surface parameterization schemes for simulating the land surface CO2 fluxes. The study in this paper developed an analytical solution approach for the Collatz et al.'s parameterization for stable solution and computational efficiency. This analytical approach is then applied to the simplified biosphere model (SSiB), enhancing its capability of simulating land surface CO2 fluxes. The enhanced SSiB model is tested with field observation data sets from two Amazonian field experiments (ABRACOS missions and Manaus Eddy Covariance Study). Simulations of the land surface fluxes of latent heat, sensible heat and soil heat by the enhanced SSiB agree very well with observations with correlation coefficients being larger than 0.80. However, the correlation coefficient for the daily means Of CO2 fluxes is only 0.42 for the Manaus data set. A day-time, "square wave" in the simulated CO2 flux diurnal curves is found. The discrepancies between simulation and observation were found to be the results of incorrect parameter setup or improper leaf to canopy scaling strategy. A modification to the scaling strategy improves significantly the accuracy of the photosynthesis-stomatal conductance model. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{zhan_analytical_2003, author = {Zhan, X. W. and Xue, Y. K. and Collatz, G. J.}, title = {An analytical approach for estimating CO2 and heat fluxes over the Amazonian region}, journal = {Ecological Modelling}, year = {2003}, volume = {162}, number = {1-2}, pages = {97--117}, url = {://WOS:000182484700007}, doi = {https://doi.org/10.1016/s0304-3800(02)00405-2} } |
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Zeri, M., Sa´, L.D.A. and Nobre, C.A. | Estimating Buoyancy Heat Flux Using the Surface Renewal Technique over Four Amazonian Forest Sites in Brazil [BibTeX] |
2013 | Boundary-Layer Meteorology Vol. 149, pp. 179-196 |
article | |
BibTeX:
@article{zeri_estimating_2013, author = {Zeri, M. and Sa´, L D. A. and Nobre, C. A.}, title = {Estimating Buoyancy Heat Flux Using the Surface Renewal Technique over Four Amazonian Forest Sites in Brazil}, journal = {Boundary-Layer Meteorology}, year = {2013}, volume = {149}, pages = {179--196} } |
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Zeri, M., Sa´, L.D.A., Manzi, A.O., Araújo, A.C., Aguiar, R.G., Von Randow, C., Sampaio, G., Cardoso, F.L. and Nobre, C.A. | Variability of Carbon and Water Fluxes Following Climate Extremes over a Tropical Forest in Southwestern Amazonia [BibTeX] |
2014 | PLoS One Vol. 9 |
article | |
BibTeX:
@article{zeri_variability_2014, author = {Zeri, M. and Sa´, L D. A. and Manzi, A. O. and Araújo, A C. and Aguiar, R. G. and Von Randow, C. and Sampaio, G and Cardoso, F. L. and Nobre, C. A.}, title = {Variability of Carbon and Water Fluxes Following Climate Extremes over a Tropical Forest in Southwestern Amazonia}, journal = {PLoS One}, year = {2014}, volume = {9} } |
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Zeri, M. and Sa, L.D.A. | The impact of data gaps and quality control filtering on the balances of energy and carbon for a Southwest Amazon forest | 2010 | Agricultural and Forest Meteorology Vol. 150(12), pp. 1543-1552 |
article | DOI URL |
Abstract: Fluxes of CO(2), water vapor, sensible heat and several heat storage terms were used to characterize the dependence of the energy balance closure and carbon balance on gaps introduced by screening for high quality or turbulent conditions. The current work is the first study where a sensitivity analysis was applied to the carbon balance and energy balance closure for an Amazonian forest site. The measurements were part of the RACCI/DRY-TO-WET Experiment, within the framework of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). The energy balance closure varied from 88% to 98%, with an average intercept of 5 W m(-2). The level of closure was dependent on the amount of data filtered out according to the quality control flag. A compromise between moderate data quality and good sampling of daytime periods was determined to be the best choice for this site. Different values of friction velocity threshold and data quality used in the screening of data resulted in a carbon balance ranging from -0.10 +/- 0.15 to 0.31 +/- 0.25 t C ha(-1), where positive values indicate a net source of carbon in the period. Applying the screening based on friction velocity and quality control changed this ecosystem in the period analyzed from a sink into a source of carbon to the atmosphere. Year-round continuous measurements would be required to verify if the net release of carbon during this transition period is part of the natural cycle for this forest or if that was caused by disturbances in the ecosystem or local climatology. Our results show that the carbon sink strength associated with this forest site could have been overestimated in previous works due to underestimation of nocturnal respiration, caused by lack of filtering of low turbulence conditions. (C) 2010 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{zeri_impact_2010, author = {Zeri, Marcelo and Sa, Leonardo D. A.}, title = {The impact of data gaps and quality control filtering on the balances of energy and carbon for a Southwest Amazon forest}, journal = {Agricultural and Forest Meteorology}, year = {2010}, volume = {150}, number = {12}, pages = {1543--1552}, url = {://WOS:000284784800005}, doi = {https://doi.org/10.1016/j.agrformet.2010.08.004} } |
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Zeri, M. and Sa, L.D.A. | Horizontal and Vertical Turbulent Fluxes Forced by a Gravity Wave Event in the Nocturnal Atmospheric Surface Layer Over the Amazon Forest | 2010 | Boundary-Layer Meteorology Vol. 138(3), pp. 413-431 |
article | DOI URL |
Abstract: A nocturnal gravity wave was detected over a south-western Amazon forest during the Large-Scale Biosphere-Atmosphere experiment in Amazonia (LBA) in the course of the dry-to-wet season campaign on October 2002. The atmospheric surface layer was stably stratified and had low turbulence activity, based on friction velocity values. However, the passage of the wave, an event with a period of about 180-300 s, caused negative turbulent fluxes of carbon dioxide (CO(2)) and positive sensible heat fluxes, as measured by the eddy-covariance system at 60 m (a parts per thousand 30 m above the tree tops). The evolution of vertical profiles of air temperature, specific humidity and wind speed during the wave movement revealed that cold and drier air occupied the sub-canopy space while high wind speeds were measured above the vegetation. The analysis of wind speed and scalars high frequency data was performed using the wavelet technique, which enables the decomposition of signals in several frequencies allowed by the data sampling conditions. The results showed that the time series of vertical velocity and air temperature were -90A degrees out of phase during the passage of the wave, implying no direct vertical transport of heat. Similarly, the time series of vertical velocity and CO(2) concentration were 90A degrees out of phase. The wave was not directly associated with vertical fluxes of this variable but the mixing induced by its passage resulted in significant exchanges in smaller scales as measured by the eddy-covariance system. The phase differences between horizontal velocity and both air temperature and CO(2) concentration were, respectively, zero and 180A degrees, implying phase and anti-phase relationships. As a result, the wave contributed to positive horizontal fluxes of heat and negative horizontal fluxes of carbon dioxide. Such results have to be considered in nocturnal boundary-layer surface-atmosphere exchange schemes for modelling purposes. | |||||
BibTeX:
@article{zeri_horizontal_2010, author = {Zeri, Marcelo and Sa, Leonardo D. A.}, title = {Horizontal and Vertical Turbulent Fluxes Forced by a Gravity Wave Event in the Nocturnal Atmospheric Surface Layer Over the Amazon Forest}, journal = {Boundary-Layer Meteorology}, year = {2010}, volume = {138}, number = {3}, pages = {413--431}, url = {://WOS:000287503200004}, doi = {https://doi.org/10.1007/s10546-010-9563-3} } |
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Zeng, N., Yoon, J.-H., Marengo, J.A., Subramaniam, A., Nobre, C.A., Mariotti, A. and Neelin, J.D. | Causes and impacts of the 2005 Amazon drought | 2008 | Environmental Research Letters Vol. 3(1) |
article | DOI URL |
Abstract: A rare drought in the Amazon culminated in 2005, leading to near record-low streamflows, small Amazon river plume, and greatly enhanced fire frequency. This episode was caused by the combination of 2002-03 El Nino and a dry spell in 2005 attributable to a warm subtropical North Atlantic Ocean. Analysis for 1979-2005 reveals that the Atlantic influence is comparable to the better-known Pacific linkage. While the Pacific influence is typically locked to the wet season, the 2005 Atlantic impact concentrated in the Amazon dry season when its hydroecosystem is most vulnerable. Such mechanisms may have wide-ranging implications for the future of the Amazon rainforest. | |||||
BibTeX:
@article{zeng_causes_2008, author = {Zeng, Ning and Yoon, Jin-Ho and Marengo, Jose A. and Subramaniam, Ajit and Nobre, Carlos A. and Mariotti, Annarita and Neelin, J. David}, title = {Causes and impacts of the 2005 Amazon drought}, journal = {Environmental Research Letters}, year = {2008}, volume = {3}, number = {1}, url = {://WOS:000253653200004 http://iopscience.iop.org/1748-9326/3/1/014002/pdf/1748-9326_3_1_014002.pdf}, doi = {https://doi.org/10.1088/1748-9326/3/1/014002} } |
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Zeng, N. | Seasonal cycle and interannual variability in the Amazon hydrologic cycle | 1999 | Journal of Geophysical Research-Atmospheres Vol. 104(D8), pp. 9097-9106 |
article | DOI URL |
Abstract: An analysis of the Amazon basin hydrologic cycle has been carried out using the NASA/Goddard Earth Observing System (GEOS-1) atmospheric reanalysis, observed rainfall of Xie and Arkin [1996], and historical Amazon River discharge. Over a seasonal cycle the precipitation is found to vary by 5 mm d(-1), and the runoff is found to vary by 2 mm d(-1), while the evaporation largely remains constant. On interannual timescales the hydrologic variability both in the atmosphere and at the land surface is found to be closely related to El Nino-Southern Oscillation (ENSO). The correlation between the Southern Oscillation Index and Xie and Arkin precipitation is 0.8 for the period 1985-1993 and 0.56 for the period 1979-1996. The precipitation lags behind the Southern Oscillation Index by 3-4 months while the Amazon River discharge lags behind the precipitation by another 3 months. The lagged relationship suggests interesting dynamic mechanisms. The reanalysis moisture convergence and observed discharge are used to diagnose basin average soil water storage. The year to year variation in the annual mean soil water storage is similar to 200 mm, comparable to the change within a climatological seasonal cycle. In one case, the basin soil water storage increases by 462 mm from September 1987 to March 1989, suggesting the remarkable ability of the tropical rain forest environment to store and take up water. | |||||
BibTeX:
@article{zeng_seasonal_1999, author = {Zeng, N.}, title = {Seasonal cycle and interannual variability in the Amazon hydrologic cycle}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1999}, volume = {104}, number = {D8}, pages = {9097--9106}, url = {://WOS:000079925600001}, doi = {https://doi.org/10.1029/1998jd200088} } |
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Zemp, D.C., Schleussner, C.-F., Barbosa, H.M.J., Hirota, M., Montade, V., Sampaio, G., Staal, A., Wang-Erlandsson, L. and Rammig, A. | Self-amplified Amazon forest loss due to vegetation-atmosphere feedbacks [BibTeX] |
2017 | Nature Communications | article | DOI |
BibTeX:
@article{zemp_self-amplified_2017, author = {Zemp, D. C. and Schleussner, C.-F. and Barbosa, H. M. J. and Hirota, M. and Montade, V. and Sampaio, G. and Staal, A. and Wang-Erlandsson, L. and Rammig, A.}, title = {Self-amplified Amazon forest loss due to vegetation-atmosphere feedbacks}, journal = {Nature Communications}, year = {2017}, doi = {https://doi.org/10.1038/ncomms14681} } |
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Zeilhofer, P., Sanches, L., Vourlitis, G.L. and De Andrade, N.L.R. | Seasonal variations in litter production and its relation with MODIS vegetation indices in a semi-deciduous forest of Mato Grosso | 2012 | Remote Sensing Letters Vol. 3(1), pp. 1-9 |
article | DOI URL |
Abstract: Litter production is related to canopy processes including the timing and amount of leaf development, reproduction and net primary production. However, quantifying spatial and temporal patterns in litter production is complicated in Amazonian semi-deciduous forests because of high spatial heterogeneity and seasonal variation in rainfall. Here, we use monthly measurements of litter production and Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) composites over a 6-year period to assess whether MODIS can be used to quantify litter production of tropical semi-deciduous forests. Original MODIS NDVI and EVI values were poorly related to the seasonal periodicity in litter production, but after using singular spectrum analysis (SSA) signal extraction techniques, clear relationships between litter production and the NDVI and EVI emerged. These results indicate that MODIS NDVI and EVI data are useful for detecting temporal patterns in litter production for Amazonian semi-deciduous forests if signal extraction analyses such as SSA are conducted. | |||||
BibTeX:
@article{zeilhofer_seasonal_2012, author = {Zeilhofer, P. and Sanches, L. and Vourlitis, G. L. and De Andrade, N. L. R.}, title = {Seasonal variations in litter production and its relation with MODIS vegetation indices in a semi-deciduous forest of Mato Grosso}, journal = {Remote Sensing Letters}, year = {2012}, volume = {3}, number = {1}, pages = {1--9}, url = {://000292874300001}, doi = {https://doi.org/10.1080/01431161.2010.523025} } |
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Zdeahal, Z., Vermeylen, R., Clayes, M., Maenhaut, W., Guyon, P. and Artaxo, P. | Characterization of novel di- and tricarboxilic acids in fine tropical aerosols [BibTeX] |
2001 | Journal of Mass Spectrometry Vol. 36(4), pp. 403-46 |
article | |
BibTeX:
@article{zdeahal_characterization_2001, author = {Zdeahal, Z. and Vermeylen, R. and Clayes, M. and Maenhaut, W. and Guyon, P. and Artaxo, P.}, title = {Characterization of novel di- and tricarboxilic acids in fine tropical aerosols}, journal = {Journal of Mass Spectrometry}, year = {2001}, volume = {36}, number = {4}, pages = {403--46} } |
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Zaveri, R.A., Wang, J., Fan, J., Zhang, Y., Shilling, J.E., Zelenyuk, A., Mei, F., Newsom, R., Pekour, M., Tomlinson, J., Comstock, J.M., Shrivastava, M., Fortner, E., Machado, L.A.T., Artaxo, P. and Martin, S.T. | Rapid growth of anthropogenic organic nanoparticles greatly alters cloud life cycle in the Amazon rainforest [BibTeX] |
2022 | Sci Adv Vol. 8(2), pp. eabj0329 |
article | DOI URL |
BibTeX:
@article{zaveri_rapid_2022, author = {Zaveri, R. A. and Wang, J. and Fan, J. and Zhang, Y. and Shilling, J. E. and Zelenyuk, A. and Mei, F. and Newsom, R. and Pekour, M. and Tomlinson, J. and Comstock, J. M. and Shrivastava, M. and Fortner, E. and Machado, L. A. T. and Artaxo, P. and Martin, S. T.}, title = {Rapid growth of anthropogenic organic nanoparticles greatly alters cloud life cycle in the Amazon rainforest}, journal = {Sci Adv}, year = {2022}, volume = {8}, number = {2}, pages = {eabj0329}, note = {Edition: 2022/01/13}, url = {https://www.ncbi.nlm.nih.gov/pubmed/35020441}, doi = {https://doi.org/10.1126/sciadv.abj0329} } |
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Zarin, D.J., Ducey, M.J., Tucker, J.M. and Salas, W.A. | Potential biomass accumulation in Amazonian regrowth forests | 2001 | Ecosystems Vol. 4(7), pp. 658-668 |
article | DOI URL |
Abstract: Biomass accumulation in the secondary forests of abandoned pastures and slash-and-burn agricultural fallows is an important but poorly constrained component of the regional carbon budget for the Brazilian Amazon. Using empirical relationships derived from a global analysis, we predicted potential aboveground biomass accumulation (ABA) for the region's regrowth forests based on soil texture and climate data. For regrowth forests on nonsandy soils, the globally derived relationship provided a nearly unbiased linear predictor of Amazonian validation data consisting of 66 stands at seven sites; there was no significant difference between stands that regrew following use as pasture land and those that regrew following slash-and-burn agriculture. For regrowth forests on nonsandy soil, the 1 sigma error range of our ABA model was 58%-171% for the Amazonian validation data. For regrowth forests on sandy soils, the validation data were limited to 19 stands at one site, and the globally derived relationship was substantially biased multiplicatively and nonlinearly. Hence we developed a regional refinement by adding to our validation data ABA values from the two Amazonian sites with sandy soil that had previously been included in the global analysis. Based on a conservative jackknife goodness-of-fit assessment (leaving out one site at a time), we calculated a 1 sigma error range of 42%-158% for our sandy soil Amazonian regrowth forest ABA model. We present our predictions of potential regrowth forest ABA as a set of 0.5 degrees resolution maps for the region at 5, 10, and 20 years following abandonment. | |||||
BibTeX:
@article{zarin_potential_2001, author = {Zarin, D. J. and Ducey, M. J. and Tucker, J. M. and Salas, W. A.}, title = {Potential biomass accumulation in Amazonian regrowth forests}, journal = {Ecosystems}, year = {2001}, volume = {4}, number = {7}, pages = {658--668}, url = {://WOS:000172503300004}, doi = {https://doi.org/10.1007/s10021-001-0035-y} } |
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Zarin, D.J., Davidson, E.A., Brondizio, E., Vieira, I.C.G., Sa, T., Feldpausch, T., Schuur, E.A., Mesquita, R., Moran, E., Delamonica, P., Ducey, M.J., Hurtt, G.C., Salimon, C. and Denich, M. | Legacy of fire slows carbon accumulation in Amazonian forest regrowth | 2005 | Frontiers in Ecology and the Environment Vol. 3(7), pp. 365-369 |
article | DOI URL |
Abstract: Amazonian farmers and ranchers use fire to clear land for agriculture and pasture as part of extensive land-use strategies that have deforested 500 000 km(2) over the past 25 years. Ash from burning biomass fertilizes crops and pastures, but declining productivity often occurs after a few years, generally leading to land abandonment and further clearing. Subsequent forest regrowth partially offsets carbon emissions from deforestation, but is often repeatedly cleared and burned. In the first quantitative, basin-wide assessment of the effect of repeated clearing and burning on forest regrowth, our analysis of data from 90 stands at nine locations across the region indicates that stands with a history of five or more fires suffer on average a greater than 50% reduction in carbon accumulation. In the absence of management interventions, Amazonian landscapes dominated by this pronounced legacy of fire are apt to accumulate very little carbon and will remain highly susceptible to recurrent burning. | |||||
BibTeX:
@article{zarin_legacy_2005, author = {Zarin, D. J. and Davidson, E. A. and Brondizio, E. and Vieira, I. C. G. and Sa, T. and Feldpausch, T. and Schuur, E. A. and Mesquita, R. and Moran, E. and Delamonica, P. and Ducey, M. J. and Hurtt, G. C. and Salimon, C. and Denich, M.}, title = {Legacy of fire slows carbon accumulation in Amazonian forest regrowth}, journal = {Frontiers in Ecology and the Environment}, year = {2005}, volume = {3}, number = {7}, pages = {365--369}, url = {://WOS:000231675200015}, doi = {https://doi.org/10.1890/1540-9295(2005)003%5B0365:lofsca%5D2.0.co;2} } |
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Zannoni, N., Leppla, D., Lembo Silveira de Assis, P.I., Hoffmann, T., Sá, M., Araújo, A. and Williams, J. | Surprising chiral composition changes over the Amazon rainforest with height, time and season | 2020 | Communications Earth & Environment Vol. 1(1), pp. 4 |
article | DOI URL |
Abstract: Many biogenic volatile organic compounds (BVOC) are chiral, existing in two mirror image forms called enantiomers. The most abundant atmospheric chiral BVOC is α-pinene (C10H16), whose enantiomeric ratio has been reported to be regiospecific. Here we show with measurements made on a 325 m tower in the Amazon rainforest that the enantiomeric ratio varies unexpectedly (by a factor of ten) with (+)-α-pinene dominating at canopy level and (−)-α-pinene at tower top. The ratio is independent of wind direction, speed and sunlight but shows diurnal temperature dependent enrichment in the (−)-α-pinene enantiomer at the lowest 80 m height. These effects cannot be caused by atmospheric reaction with oxidants, or aerosol uptake. The reversal of chiral ratio at 80 m reveals the presence of a potent uncharacterized local (+)-α-pinene rich source, possibly linked to herbivory and termites. These results suggest the presence of a strong uncharacterized BVOC source that is overlooked in current emission models. | |||||
BibTeX:
@article{zannoni_surprising_2020, author = {Zannoni, Nora and Leppla, Denis and Lembo Silveira de Assis, Pedro Ivo and Hoffmann, Thorsten and Sá, Marta and Araújo, Alessandro and Williams, Jonathan}, title = {Surprising chiral composition changes over the Amazon rainforest with height, time and season}, journal = {Communications Earth & Environment}, year = {2020}, volume = {1}, number = {1}, pages = {4}, url = {https://doi.org/10.1038/s43247-020-0007-9}, doi = {https://doi.org/10.1038/s43247-020-0007-9} } |
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Zanin, P.R. | Soil Water Uptake by Amazonian Trees and Simulation of Impacts on Energy Fluxes and Soil Moisture Dynamics at the LBA Flux Towers | 2021 | Revista Brasileira de Meteorologia Vol. 36(3), pp. 441-454 |
article | DOI URL |
Abstract: Observational and modeling studies show that a deeper soil water uptake by tree roots is required for evapotranspiration in the Amazon Basin. Therefore, this study performed three numerical modeling experiments with different depths of soil water uptake by Amazonian tree roots using the Eta/CPTEC regional climate model. In the “Control” and “Deep Soil Shallow Root” experiments the depth of soil water uptake by tree roots is set up with 2 m, while in the “Deep Soil Deep Root” experiment this depth is set up with 7.2 m, according to the observational studies. The energy balance at the LBA flux towers is better simulated in the “Deep Soil Deep Root” experiment than in other experiments. Moreover, with the “Deep Soil Deep Root” experiment the seasonality of evapotranspiration is reduced in the regions where there is strong seasonality of precipitation, while the seasonality of moisture is reduced in shallow soil layers and increases in the deeper soil layers. In addition, in the regions with strong seasonality of precipitation the deeper soil layers have an inter-annual hydrological memory, and in all regions the soil moisture memory is inversely related to the amount of precipitation, with different behaviors in each soil layer. In conclusion, the deeper soil water uptake by the Amazonian trees is important for the energy balance and soil moisture dynamics in the Amazon Basin. Resumo Estudos observacionais e de modelagem mostram que uma captação mais profunda de água do solo pelas raízes das árvores é necessária para a evapotranspiração na Bacia Amazônica. Portanto, este estudo realizou três experimentos de modelagem com diferentes profundidades de captação de água do solo pelas raízes das árvores da Amazônia usando o modelo Eta/CPTEC. Nos experimentos “Controle” e “Solo Profundo Raiz Rasa” a profundidade de captação de água no solo pelas raízes das árvores é estabelecida em 2 m, enquanto que no experimento “Solo Profundo Raiz Profunda” essa profundidade é estabelecida em 7,2 m, de acordo com estudos observacionais. O balanço de energia nas torres de fluxo do LBA é melhor simulado no experimento “Solo Profundo Raiz Profunda” do que nos outros experimentos. Além disso, com o experimento “Solo Profundo Raiz Profunda” a sazonalidade da evapotranspiração é reduzida nas regiões com forte sazonalidade da precipitação, enquanto que a sazonalidade da umidade do solo é reduzida nas camadas rasas e aumentada nas camadas mais profundas do solo. Também foi verificado que nas regiões com forte sazonalidade da precipitação as camadas mais profundas do solo têm uma memória hidrológica interanual, e que a memória da umidade do solo em todas as regiões analisadas tem uma relação inversa com a quantidade de precipitação, com diferentes comportamentos em cada camada do solo. Em conclusão, a captação mais profunda de água no solo pelas árvores Amazônicas é importante para o balanço de energia e dinâmica da umidade do solo na Bacia Amazônica. |
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BibTeX:
@article{zanin_soil_2021, author = {Zanin, Paulo Rodrigo}, title = {Soil Water Uptake by Amazonian Trees and Simulation of Impacts on Energy Fluxes and Soil Moisture Dynamics at the LBA Flux Towers}, journal = {Revista Brasileira de Meteorologia}, year = {2021}, volume = {36}, number = {3}, pages = {441--454}, url = {http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-77862021000300441&lang=pt}, doi = {https://doi.org/10.1590/0102-77863630029} } |
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Zanchi, F., Waterloo, M., Kruijt, B., Kesselmeier, J., Luizão, F., Manzi, A. and Dolman, A. | Soil CO2 efflux in central Amazonia: environmental and methodological effects [BibTeX] |
2012 | Acta Amazonica Vol. 42(2), pp. 173-184 |
article | DOI |
BibTeX:
@article{zanchi_soil_2012, author = {Zanchi, F.B. and Waterloo, M.J. and Kruijt, B. and Kesselmeier, J. and Luizão, F.J. and Manzi, A.O. and Dolman, A.J.}, title = {Soil CO2 efflux in central Amazonia: environmental and methodological effects}, journal = {Acta Amazonica}, year = {2012}, volume = {42}, number = {2}, pages = {173--184}, doi = {https://doi.org/10.1590/S0044-59672012000200001} } |
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Zanchi, F.B., Waterloo, M.J., Dolman, A.J., Groenendijk, M., Kesselmeier, J., Kruijt, B., Bolson, M.A., Luizão, F.J. and Manzi, A.O. | Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils [BibTeX] |
2011 | Ambi-Agua Vol. 6(1), pp. 6-29 |
article | DOI |
BibTeX:
@article{zanchi_influence_2011, author = {Zanchi, Fabrício Berton and Waterloo, Maarten Johannes and Dolman, Albertus Johannes and Groenendijk, Margriet and Kesselmeier, Jurgen and Kruijt, Bart and Bolson, Marcos Alexandre and Luizão, Flávio Jesus and Manzi, Antônio Ocimar}, title = {Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils}, journal = {Ambi-Agua}, year = {2011}, volume = {6}, number = {1}, pages = {6--29}, doi = {https://doi.org/10.4136/ambi-agua.170} } |
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Zanchi, F., Meesters, A., Waterloo, M., Kruijt, B., Kesselmeier, J., Luizão, F. and Dolman, A. | Soil CO2 exchange in seven pristine Amazonian rain forest sites in relation to soil temperature [BibTeX] |
2014 | Agricultural and Forest Meteorology Vol. 192-193, pp. 96-107 |
article | |
BibTeX:
@article{zanchi_soil_2014, author = {Zanchi, F.B. and Meesters, A.G.C.A. and Waterloo, M.J. and Kruijt, B. and Kesselmeier, J. and Luizão, F.J. and Dolman, A.J.}, title = {Soil CO2 exchange in seven pristine Amazonian rain forest sites in relation to soil temperature}, journal = {Agricultural and Forest Meteorology}, year = {2014}, volume = {192-193}, pages = {96--107} } |
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Zanchi, F.B., da Rocha, H.R., Freitas, H.C.d., Kruijt, B., Waterloo, M.J. and Manzi, A.O. | Measurements of soil respiration and simple models dependent on moisture and temperature for an Amazonian southwest tropical forest [BibTeX] |
2009 | Biogeosciences Discuss. Vol. 6, pp. 6147-6177 |
article | |
BibTeX:
@article{zanchi_measurements_2009, author = {Zanchi, F. B. and da Rocha, H. R. and Freitas, H. C. de and Kruijt, B. and Waterloo, M. J. and Manzi, A. O.}, title = {Measurements of soil respiration and simple models dependent on moisture and temperature for an Amazonian southwest tropical forest}, journal = {Biogeosciences Discuss.}, year = {2009}, volume = {6}, pages = {6147--6177} } |
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Zanchi, W., Aguiar, M.J., L.J.G., v.R., Kruijt, C., Cardoso, B., Manzi, F.L. and F.B., A.O. | Estimativa do Índice de Área Foliar (IAF) e Biomassa em pastagem no estado de Rondônia, Brasil [BibTeX] |
2009 | Acta Amazonica Vol. 39(2), pp. 335 - 348 |
article | |
BibTeX:
@article{zanchi_estimativa_2009, author = {Zanchi, Waterloo, M.J., Aguiar, L.J.G., von Randow, C., Kruijt, B., Cardoso, F.L., Manzi, A.O., F.B.}, title = {Estimativa do Índice de Área Foliar (IAF) e Biomassa em pastagem no estado de Rondônia, Brasil}, journal = {Acta Amazonica}, year = {2009}, volume = {39}, number = {2}, pages = {335 -- 348} } |
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Zahn, E., Dias, N.l., Araújo, A., Sá, L., Söergel, M., Trebs, I., Wolff, S. and Manzi, A. | Scalar turbulent behavior in the roughness sublayer of an Amazonian forest [BibTeX] |
2016 | Atmospheric Chemistry and Physics Vol. 16, pp. 11349-11366 |
article | DOI |
BibTeX:
@article{zahn_scalar_2016, author = {Zahn, E. and Dias, N. l. and Araújo, A. and Sá, L. and Söergel, M. and Trebs, I. and Wolff, S. and Manzi, A.}, title = {Scalar turbulent behavior in the roughness sublayer of an Amazonian forest}, journal = {Atmospheric Chemistry and Physics}, year = {2016}, volume = {16}, pages = {11349--11366}, doi = {https://doi.org/10.5194/acp-16-11349-2016} } |
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Yokelson, R.J., Karl, T., Artaxo, P., Blake, D.R., Christian, T.J., Griffith, D.W.T., Guenther, A. and Hao, W.M. | The Tropical Forest and Fire Emissions Experiment: overview and airborne fire emission factor measurements | 2007 | Atmospheric Chemistry and Physics Vol. 7(19), pp. 5175-5196 |
article | URL |
Abstract: The Tropical Forest and Fire Emissions Experiment (TROFFEE) used laboratory measurements followed by airborne and ground based field campaigns during the 2004 Amazon dry season to quantify the emissions from pristine tropical forest and several plantations as well as the emissions, fuel consumption, and fire ecology of tropical deforestation fires. The airborne campaign used an Embraer 110B aircraft outfitted with whole air sampling in canisters, mass-calibrated nephelometry, ozone by UV absorbance, Fourier transform infrared spectroscopy (FTIR), and proton-transfer mass spectrometry (PTR-MS) to measure PM(10), O(3), CO(2), CO, NO, NO(2), HONO, HCN, NH(3), OCS, DMS, CH(4), and up to 48 non-methane organic compounds (NMOC). The Brazilian smoke/haze layers extended to 2 - 3 km altitude, which is much lower than the 5 - 6 km observed at the same latitude, time of year, and local time in Africa in 2000. Emission factors (EF) were computed for the 19 tropical deforestation fires sampled and they largely compare well to previous work. However, the TROFFEE EF are mostly based on a much larger number of samples than previously available and they also include results for significant emissions not previously reported such as: nitrous acid, acrylonitrile, pyrrole, methylvinylketone, methacrolein, crotonaldehyde, methylethylketone, methylpropanal, '' acetol plus methylacetate,'' furaldehydes, dimethylsulfide, and C(1)-C(4) alkyl nitrates. Thus, we recommend these EF for all tropical deforestation fires. The NMOC emissions were similar to 80% reactive, oxygenated volatile organic compounds (OVOC). Our EF for PM(10) (17.8 +/- 4 g/kg) is similar to 25% higher than previously reported for tropical forest fires and may reflect a trend towards, and sampling of, larger fires than in earlier studies. A large fraction of the total burning for 2004 likely occurred during a two-week period of very low humidity. The combined output of these fires created a massive '' mega-plume '' textgreater 500 km across that we sampled on 8 September. The mega-plume contained high PM(10) and 10 - 50 ppbv of many reactive species such as O(3), NH(3), NO(2), CH(3)OH, and organic acids. This is an intense and globally important chemical processing environment that is still poorly understood. The mega-plume or '' white ocean '' of smoke covered a large area in Brazil, Bolivia, and Paraguay for about one month. The smoke was transported textgreater 2000 km to the southeast while remaining concentrated enough to cause a 3 - 4-fold increase in aerosol loading in the S (a) over tildeo Paulo area for several days. | |||||
BibTeX:
@article{yokelson_tropical_2007, author = {Yokelson, R. J. and Karl, T. and Artaxo, P. and Blake, D. R. and Christian, T. J. and Griffith, D. W. T. and Guenther, A. and Hao, W. M.}, title = {The Tropical Forest and Fire Emissions Experiment: overview and airborne fire emission factor measurements}, journal = {Atmospheric Chemistry and Physics}, year = {2007}, volume = {7}, number = {19}, pages = {5175--5196}, url = {://WOS:000251239000010} } |
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Yee, Isaacman-VanWertz, G., Wernis, R. A., Meng, M., Rivera, V., Kreisberg, N. M., Hering, S. V., Bering, M. S., Glasius, M., Upshur, M. A., Gray Bé, A., Thomson, R. J., Geiger, F. M., Offenberg, J. H., Lewandowski, M., Kourtchev, I., Kalberer, M., de Sá, S., Martin, S. T., Alexander, M. L., Palm, B. B., Hu, W., Campuzano-Jost, P., Day, D. A., Jimenez, J. L., Liu, Y., McKinney, K. A., Artaxo, P., Viegas, J., Manzi, A., Oliveira, M. B., de Souza, R., Machado, L. A. T., Longo, K., and Goldstein, A. H., L. D. | Observations of sesquiterpenes and their oxidation products in central Amazonia during the wet and dry seasons [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 10433-10457 |
article | DOI |
BibTeX:
@article{yee_observations_2018, author = {Yee, Isaacman-VanWertz, G., Wernis, R. A., Meng, M., Rivera, V., Kreisberg, N. M., Hering, S. V., Bering, M. S., Glasius, M., Upshur, M. A., Gray Bé, A., Thomson, R. J., Geiger, F. M., Offenberg, J. H., Lewandowski, M., Kourtchev, I., Kalberer, M., de Sá, S., Martin, S. T., Alexander, M. L., Palm, B. B., Hu, W., Campuzano-Jost, P., Day, D. A., Jimenez, J. L., Liu, Y., McKinney, K. A., Artaxo, P., Viegas, J., Manzi, A., Oliveira, M. B., de Souza, R., Machado, L. A. T., Longo, K., and Goldstein, A. H., L. D.}, title = {Observations of sesquiterpenes and their oxidation products in central Amazonia during the wet and dry seasons}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {10433--10457}, doi = {https://doi.org/10.5194/acp-18-10433-2018} } |
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Ye, J., Batista, C.E., Guimarães, P.C., Ribeiro, I.O., Vidoudez, C., Barbosa, R.G., Oliveira, R.L., Ma, Y., Jardine, K.J., Surratt, J.D., Guenther, A.B., Souza, R.A.F. and Martin, S.T. | Near-canopy horizontal concentration heterogeneity of semivolatile oxygenated organic compounds and implications for 2-methyltetrols primary emissions | 2021 | Environmental Science: Atmospheres Vol. 1(1), pp. 8-20 |
article | DOI URL |
Abstract: Semivolatile oxygenated organic compounds (SV-OVOCs) are important atmospheric species, in particular for the production and chemistry of atmospheric particulate matter and related impacts on air quality and climate. In this study, SV-OVOCs were collected in the horizontal plane of the roughness layer over the tropical forest in the central Amazon during the wet season of 2018. A sampler mounted to a copter-type, hovering unmanned aerial vehicle was used. Underlying the collection region, a plateau forest transitioned into a slope forest across several hundred meters. The concentrations of pinonic and pinic acids, which are monoterpene oxidation products, had no statistical difference over the two forests. By comparison, across the study period, differences in the concentration of 2-methyltetrols, which are products of isoprene oxidation, ranged from −70% to +480% over the two forests. The chemical lifetime of 2-methyltetrols in the atmosphere is sufficiently long that heterogeneity in the isoprene emission rate from the two forests followed by atmospheric oxidation does not explain the concentration heterogeneity of 2-methyltetrols. Standing waves and local meteorology also cannot account for the heterogeneity. Of the possibilities considered, the most plausible explanation is the direct emission from the forest of 2-methyltetrols produced through biological processes within the plants. Under this explanation, the rate of direct SV-OVOC emissions should be modulated by forest type and related environmental stressors. Direct emissions of SV-OVOCs should be more broadly considered for constraining and improving models of atmospheric composition, transport, and chemistry over tropical forests. | |||||
BibTeX:
@article{ye_near-canopy_2021, author = {Ye, Jianhuai and Batista, Carla E. and Guimarães, Patricia C. and Ribeiro, Igor O. and Vidoudez, Charles and Barbosa, Rafael G. and Oliveira, Rafael L. and Ma, Yongjing and Jardine, Kolby J. and Surratt, Jason D. and Guenther, Alex B. and Souza, Rodrigo A. F. and Martin, Scot T.}, title = {Near-canopy horizontal concentration heterogeneity of semivolatile oxygenated organic compounds and implications for 2-methyltetrols primary emissions}, journal = {Environmental Science: Atmospheres}, year = {2021}, volume = {1}, number = {1}, pages = {8--20}, url = {http://dx.doi.org/10.1039/D0EA00006J}, doi = {https://doi.org/10.1039/D0EA00006J} } |
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Yáñez-Serrano, A.M., Nölscher, A.C., Williams, J., Wolff, S., Alves, E., Martins, G.A., Bourtsoukidis, E., Brito, J., Jardine, K., Artaxo, P. and Kesselmeier, J. | Diel and seasonal changes of biogenic volatile organic compounds within and above an Amazonian rainforest [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 3359-3378 |
article | DOI |
BibTeX:
@article{yanez-serrano_diel_2015, author = {Yáñez-Serrano, A. M. and Nölscher, A. C. and Williams, J. and Wolff, S. and Alves, E. and Martins, G. A. and Bourtsoukidis, E. and Brito, J. and Jardine, K. and Artaxo, P. and Kesselmeier, J.}, title = {Diel and seasonal changes of biogenic volatile organic compounds within and above an Amazonian rainforest}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {3359--3378}, doi = {https://doi.org/10.5194/acp-15-3359-2015} } |
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Yáñez-Serrano, A.M., Bourtsoukidis, E., Alves, E.G., Bauwens, M., Stavrakou, T., Llusià, J., Filella, I., Guenther, A., Williams, J., Artaxo, P., Sindelarova, K., Doubalova, J., Kesselmeier, J. and Peñuelas, J. | Amazonian biogenic volatile organic compounds under global change | 2020 | Global Change Biology Vol. 26(9), pp. 4722-4751 |
article | DOI URL |
Abstract: Abstract Biogenic volatile organic compounds (BVOCs) play important roles at cellular, foliar, ecosystem and atmospheric levels. The Amazonian rainforest represents one of the major global sources of BVOCs, so its study is essential for understanding BVOC dynamics. It also provides insights into the role of such large and biodiverse forest ecosystem in regional and global atmospheric chemistry and climate. We review the current information on Amazonian BVOCs and identify future research priorities exploring biogenic emissions and drivers, ecological interactions, atmospheric impacts, depositional processes and modifications to BVOC dynamics due to changes in climate and land cover. A feedback loop between Amazonian BVOCs and the trends of climate and land-use changes in Amazonia is then constructed. Satellite observations and model simulation time series demonstrate the validity of the proposed loop showing a combined effect of climate change and deforestation on BVOC emission in Amazonia. A decreasing trend of isoprene during the wet season, most likely due to forest biomass loss, and an increasing trend of the sesquiterpene to isoprene ratio during the dry season suggest increasing temperature stress-induced emissions due to climate change. | |||||
BibTeX:
@article{yanez-serrano_amazonian_2020, author = {Yáñez-Serrano, Ana M. and Bourtsoukidis, Efstratios and Alves, Eliane G. and Bauwens, Maite and Stavrakou, Trissevgeni and Llusià, Joan and Filella, Iolanda and Guenther, Alex and Williams, Jonathan and Artaxo, Paulo and Sindelarova, Katerina and Doubalova, Jana and Kesselmeier, Jürgen and Peñuelas, Josep}, title = {Amazonian biogenic volatile organic compounds under global change}, journal = {Global Change Biology}, year = {2020}, volume = {26}, number = {9}, pages = {4722--4751}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.15185}, doi = {https://doi.org/10.1111/gcb.15185} } |
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Yañez-Serrano, N., A. C., B., Alves, E., E. G., G., Bonn, L., Wolff, B., Sa, S., Yamasoe, M., Williams, M., Andreae, J., M. O., K. and A. M., J. | Monoterpene chemical speciation in a tropical rainforest: variation with season, height, and time of day at the Amazon Tall Tower Observatory (ATTO) [BibTeX] |
2018 | Atmospheric Chemistry and Physics Vol. 18(5), pp. 3403-3418 |
article | DOI |
BibTeX:
@article{yanez-serrano_monoterpene_2018, author = {Yañez-Serrano, Nölscher, A. C., Bourtsoukidis, E., Alves, E. G., Ganzeveld, L., Bonn, B., Wolff, S., Sa, M., Yamasoe, M., Williams, J., Andreae, M. O., Kesselmeier, J., A. M.}, title = {Monoterpene chemical speciation in a tropical rainforest: variation with season, height, and time of day at the Amazon Tall Tower Observatory (ATTO)}, journal = {Atmospheric Chemistry and Physics}, year = {2018}, volume = {18}, number = {5}, pages = {3403--3418}, doi = {https://doi.org/10.5194/acp-18-3403-2018} } |
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Yañez-Serrano, A. C. Nölscher, E. Bourtsoukidis, B. Destroff, N. Zannoni, V. Gros, C. Boissard, M. Lanza, J. Brito, S. M. Noe, E. House, C. N. Hewitt, K. Jardine, T. Behrendt, J. Williams, P. Artaxo, M. O. Andreae, J. Kesselmeier, A. M. | Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, boreal, temperate and marine environments [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 10965-10984 |
article | DOI |
BibTeX:
@article{yanez-serrano_atmospheric_2016, author = {Yañez-Serrano, A. C. Nölscher, E. Bourtsoukidis, B. Destroff, N. Zannoni, V. Gros, C. Boissard, M. Lanza, J. Brito, S. M. Noe, E. House, C. N. Hewitt, K. Jardine, T. Behrendt, J. Williams, P. Artaxo, M. O. Andreae, J. Kesselmeier, A. M.}, title = {Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, boreal, temperate and marine environments}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {10965--10984}, doi = {https://doi.org/10.5194/acp-2016-317} } |
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Yamasoe, M.A., von Randow, C., Manzi, A.O., Schafer, J.S., Eck, T.F. and Holben, B.N. | Effect of smoke and clouds on the transmissivity of photosynthetically active radiation inside the canopy | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 1645-1656 |
article | URL |
Abstract: Biomass burning activities emit high concentrations of aerosol particles to the atmosphere. Such particles can interact with solar radiation, decreasing the amount of light reaching the surface and increasing the fraction of diffuse radiation through scattering processes, and thus has implications for photosynthesis within plant canopies. This work reports results from photosynthetically active radiation ( PAR) and aerosol optical depth (AOD) measurements conducted simultaneously at Reserva Biologica do Jaru (Rondonia State, Brazil) during LBA/SMOCC (Large-Scale Biosphere-Atmosphere Experiment in Amazonia/Smoke, Aerosols, Clouds, Rainfall, and Climate) and RaCCI ( Radiation, Cloud, and Climate Interactions in the Amazon during the Dry-to-Wet Transition Season) field experiments from 15 September to 15 November 2002. AOD values were retrieved from an AERONET ( Aerosol Robotic Network) radiometer, MODIS ( Moderate Resolution Spectroradiometer) and a portable sunphotometer from the United States Department of Agriculture - Forest Service. Significant reduction of PAR irradiance at the top of the canopy was observed due to the smoke aerosol particles layer. This radiation reduction affected turbulent fluxes of sensible and latent heats. The increase of AOD also enhanced the transmission of PAR inside the canopy. As a consequence, the availability of diffuse radiation was enhanced due to light scattering by the aerosol particles. A complex relationship was identified between light availability inside the canopy and net ecosystem exchange ( NEE). The results showed that the increase of aerosol optical depth corresponded to an increase of CO2 uptake by the vegetation. However, for even higher AOD values, the corresponding NEE was lower than for intermediate values. As expected, water vapor pressure deficit (VPD), retrieved at 28 m height inside the canopy, can also affect photosynthesis. A decrease in NEE was observed as VPD increased. Further studies are needed to better understand these findings, which were reported for the first time for the Amazon region under smoky conditions. | |||||
BibTeX:
@article{yamasoe_effect_2006, author = {Yamasoe, M. A. and von Randow, C. and Manzi, A. O. and Schafer, J. S. and Eck, T. F. and Holben, B. N.}, title = {Effect of smoke and clouds on the transmissivity of photosynthetically active radiation inside the canopy}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {1645--1656}, url = {://WOS:000237695900002} } |
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Yamasoe, M.A. and Rosario, N.E.d. | Changes in solar radiation partitioning reaching the surface due to biomass burning aerosol particles in the Amazon Basin | 2009 | Vol. 1100Current Problems in Atmospheric Radiation, pp. 657-660 |
incollection | URL |
Abstract: In this paper, results from the partition of downward Surface solar radiation between direct and diffuse components under distinct aerosol loadings will be presented. The field experiment was conducted during 2007 dry season in the Reserva Biologica do Jaru, located in the Southwestern portion of the Amazon Basin (-10.145 degrees, -61.908 degrees), in a region with tropical rainforest vegetation. A Multi-Filter Rotating Shadow-band Radiometer (MFRSR) was used to measure global and diffuse components of solar radiation in narrow bands (centered at 415, 670, 870 and 1036nm) as well as broadband (from about 350 to 1100nm) spectral regions. Due to biomass burning emissions, high values Of aerosol optical depth were observed (accompanying paper by Rosario et al., 2008). Consequently, a significant increase in diffuse solar irradiance was also observed. For example, at channel around 670 nm, the diffuse fraction corresponded to about 80%, even at noon, for aerosol optical depth of about 2 at the same wavelength, which is expected to be about 20% at this time of the day in clean conditions. For clean days, diffuse fraction can reach maximum about 35% during early morning or late afternoon. For broadband irradiance, 70% of radiation is diffuse when AOD is about 2 around noon and Would be about 15-30% for low AOD values. | |||||
BibTeX:
@incollection{nakajima_changes_2009, author = {Yamasoe, M. A. and Rosario, N. E. do}, title = {Changes in solar radiation partitioning reaching the surface due to biomass burning aerosol particles in the Amazon Basin}, booktitle = {Current Problems in Atmospheric Radiation}, year = {2009}, volume = {1100}, pages = {657--660}, url = {://WOS:000265672300160} } |
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Yamasoe, M.A., Artaxo, P., Miguel, A.H. and Allen, A.G. | Chemical composition of aerosol particles from direct emissions of vegetation fires in the Amazon Basin: water-soluble species and trace elements | 2000 | Atmospheric Environment Vol. 34(10), pp. 1641-1653 |
article | DOI URL |
Abstract: Biomass burning is an important global source of aerosol particles to the atmosphere. Aerosol particles were collected in plumes of tropical forest and cerrado biomass burning fires in the Amazon Basin during August-September, 1992. Fine (d(p) textless2 mu m, where d(p) is the aerodynamic diameter of the particle) and coarse (2 mu m textless d(p) textless10 mu m) aerosol particles were collected using stacked filter units. Up to 19 trace elements were determined using particle-induced X-ray emission analysis. Ion chromatography was used to determine up to 11 water-soluble ion components. The dominant species were black carbon, K(+), Cl(-), and SO(4)(2-). Organic matter represents in average 70-92% of the fine mode particle mass. The composition of the emitted particles in cerrado fires presents a well-defined pattern related to both the combustion phase and cerrado categories, which is not observed in the case of forest fires. Higher concentrations relative to the fine particulate mass were observed during the flaming emissions compared to the smoldering ones, for almost all experiments. Global emission flux estimates showed that biomass burning could be an important source of heavy metals and black carbon to the atmosphere. Estimates showed that savanna and tropical forest biomass burning could be responsible for the emission of about 1 Gg yr(-1) of copper, 3 Gg yr(-1) of zinc and 2.2 Tg yr(-1) of black carbon to the atmosphere. In average, these values correspond to 2, 3 and 12%, respectively, of the global budget of these species. (C) 2000 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{yamasoe_chemical_2000, author = {Yamasoe, M. A. and Artaxo, P. and Miguel, A. H. and Allen, A. G.}, title = {Chemical composition of aerosol particles from direct emissions of vegetation fires in the Amazon Basin: water-soluble species and trace elements}, journal = {Atmospheric Environment}, year = {2000}, volume = {34}, number = {10}, pages = {1641--1653}, url = {://WOS:000085995400014}, doi = {https://doi.org/10.1016/s1352-2310(99)00329-5} } |
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Yadvinder Malhi, Christopher E. Doughty, Gregory R. Goldsmith, Daniel B. Metcalfe, Cécile A. J. Girardin, Toby R. Marthews, Jhon del Aguila-Pasquel, Luiz E. O. C. Aragão, Alejandro Araujo-Murakami, Paulo Brando, Antonio C. L. da Costa, Javier E. Silva-Espejo, Filio Farfán Amézquita, David R. Galbraith, Carlos A. Quesada, Wanderley Rocha, Norma Salinas-Revilla, Divino Silvério, Patrick Meir and Phillips, O.L. | The linkages between photosynthesis, productivity, growth and biomass in lowland Amazonian forests [BibTeX] |
2015 | Global Change Biology Vol. 21(6), pp. 2283-2295 |
article | |
BibTeX:
@article{yadvinder_malhi_linkages_2015, author = {Yadvinder Malhi and Christopher E. Doughty and Gregory R. Goldsmith and Daniel B. Metcalfe and Cécile A. J. Girardin and Toby R. Marthews and Jhon del Aguila-Pasquel and Luiz E. O. C. Aragão and Alejandro Araujo-Murakami and Paulo Brando and Antonio C. L. da Costa and Javier E. Silva-Espejo and Filio Farfán Amézquita and David R. Galbraith and Carlos A. Quesada and Wanderley Rocha and Norma Salinas-Revilla and Divino Silvério and Patrick Meir and Phillips, Oliver L.}, title = {The linkages between photosynthesis, productivity, growth and biomass in lowland Amazonian forests}, journal = {Global Change Biology}, year = {2015}, volume = {21}, number = {6}, pages = {2283--2295} } |
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Xu, L., Samanta, A., Costa, M.H., Ganguly, S., Nemani, R.R. and Myneni, R.B. | Widespread decline in greenness of Amazonian vegetation due to the 2010 drought | 2011 | Geophysical Research Letters Vol. 38 |
article | DOI URL |
Abstract: During this decade, the Amazon region has suffered two severe droughts in the short span of five years - 2005 and 2010. Studies on the 2005 drought present a complex, and sometimes contradictory, picture of how these forests have responded to the drought. Now, on the heels of the 2005 drought, comes an even stronger drought in 2010, as indicated by record low river levels in the 109 years of bookkeeping. How has the vegetation in this region responded to this record-breaking drought? Here we report widespread, severe and persistent declines in vegetation greenness, a proxy for photosynthetic carbon fixation, in the Amazon region during the 2010 drought based on analysis of satellite measurements. The 2010 drought, as measured by rainfall deficit, affected an area 1.65 times larger than the 2005 drought - nearly 5 million km(2) of vegetated area in Amazonia. The decline in greenness during the 2010 drought spanned an area that was four times greater (2.4 million km(2)) and more severe than in 2005. Notably, 51% of all drought-stricken forests showed greenness declines in 2010 (1.68 million km(2)) compared to only 14% in 2005 (0.32 million km(2)). These declines in 2010 persisted following the end of the dry season drought and return of rainfall to normal levels, unlike in 2005. Overall, the widespread loss of photosynthetic capacity of Amazonian vegetation due to the 2010 drought may represent a significant perturbation to the global carbon cycle. Citation: Xu, L., A. Samanta, M. H. Costa, S. Ganguly, R. R. Nemani, and R. B. Myneni (2011), Widespread decline in greenness of Amazonian vegetation due to the 2010 drought, Geophys. Res. Lett., 38, L07402, doi:10.1029/2011GL046824. | |||||
BibTeX:
@article{xu_widespread_2011, author = {Xu, Liang and Samanta, Arindam and Costa, Marcos H. and Ganguly, Sangram and Nemani, Ramakrishna R. and Myneni, Ranga B.}, title = {Widespread decline in greenness of Amazonian vegetation due to the 2010 drought}, journal = {Geophysical Research Letters}, year = {2011}, volume = {38}, url = {://WOS:000289357200001}, doi = {https://doi.org/10.1029/2011gl046824} } |
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Xiao, X.M., Zhang, Q.Y., Saleska, S., Hutyra, L., De Camargo, P., Wofsy, S., Frolking, S., Boles, S., Keller, M. and Moore, B. | Satellite-based modeling of gross primary production in a seasonally moist tropical evergreen forest | 2005 | Remote Sensing of Environment Vol. 94(1), pp. 105-122 |
article | DOI URL |
Abstract: A CO2 eddy flux tower study has recently reported that an old-growth stand of seasonally moist tropical evergreen forest in Santarem, Brazil, maintained high gross primary production (GPP) during the dry seasons [Saleska, S. R., Miller, S. D., Matross, D. M., Goulden, M. L., Wofsy. S. C., da Rocha, H. R., de Camargo, P. B., Crill, P., Daube, B. C., de Freitas, H. C., Hutyra, L., Keller, M., Kirchhoff, V., Menton, M., Munger, J. W., Pyle, E. H., Rice, A. H., & Silva, H. (2003). Carbon in amazon forests: Unexpected seasonal fluxes and disturbance-induced losses. Science, 302, 1554-1557]. It was proposed that seasonally moist tropical evergreen forests have evolved two adaptive mechanisms in an environment with strong seasonal variations of light and water: deep roots system for access to water in deep soils and leaf phenology for access to light. Identifying tropical forests with these adaptive mechanisms could substantially improve our capacity of modeling the seasonal dynamics of carbon and water fluxes in the tropical zone. In this paper, we have analyzed multi-year satellite images from the VEGETATION (VGT) sensor onboard the SPOT-4 satellite (4/1998-12/2002) and the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Terra satellite (2000-2003). We reported temporal analyses of vegetation indices and simulations of the satellite-based vegetation photosynthesis model (VPM). The Enhanced Vegetation Index (EVI) identified subtle changes in the seasonal dynamics of leaf phenology (leaf emergence, leaf aging and leaf fall) in the forest, as suggested by the leaf litterfall data. The land surface water index (LSWI) indicated that the forest experienced no water stress in the dry seasons of 1998-2002. The VPM model, which uses EVI, LSWI and site-specific climate data (air temperature and photosynthetically active radiation, PAR) for 2001-2002, predicted high GPP in the late dry seasons, consistent with observed high evapotranspiration and estimated GPP from the CO2 eddy flux tower. (C) 2004 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{xiao_satellite-based_2005, author = {Xiao, X. M. and Zhang, Q. Y. and Saleska, S. and Hutyra, L. and De Camargo, P. and Wofsy, S. and Frolking, S. and Boles, S. and Keller, M. and Moore, B.}, title = {Satellite-based modeling of gross primary production in a seasonally moist tropical evergreen forest}, journal = {Remote Sensing of Environment}, year = {2005}, volume = {94}, number = {1}, pages = {105--122}, url = {://WOS:000226270500009}, doi = {https://doi.org/10.1016/j.rse.2004.08.015} } |
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Xiao, X., Hagen, S., Zhang, Q., Keller, M. and Moore III, B. | Detecting leaf phenology of seasonally moist tropical forests in South America with multi-temporal MODIS images | 2006 | Remote Sensing of Environment Vol. 103(4), pp. 465-473 |
article | DOI URL |
Abstract: Leaf phenology of tropical evergreen forests affects carbon and water fluxes. In an earlier study of a seasonally moist evergreen tropical forest site in the Amazon basin, time series data of Enhanced Vegetation Index (EVI) from the VEGETATION and Moderate Resolution Imaging Spectroradiometer (MODIS) sensors showed an unexpected seasonal pattern, with higher EVI in the late dry season than in the wet season. In this study we conducted a regionat-scale analysis of tropical evergreen forests in South America, using time series data of EVI from MODIS in 2002. The results show a large dynamic range and spatial variations of annual maximum EVI for evergreen forest canopies in the region. In tropical evergreen forests, maximum EVI in 2002 typically occurs during the late dry season to early wet season. This suggests that leaf phenology in tropical evergreen forests is not determined by the seasonality of precipitation. Instead, leaf phenological process may be driven by availability of solar radiation and/or avoidance of herbivory. (c) 2006 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{xiao_detecting_2006, author = {Xiao, Xiangming and Hagen, Stephen and Zhang, Qingyuan and Keller, Michael and Moore, III, Berrien}, title = {Detecting leaf phenology of seasonally moist tropical forests in South America with multi-temporal MODIS images}, journal = {Remote Sensing of Environment}, year = {2006}, volume = {103}, number = {4}, pages = {465--473}, url = {://WOS:000239882000007}, doi = {https://doi.org/10.1016/j.rse.2006.04.013} } |
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Wu, L., Kim, X., H. K., G., Godoi, H., R. H. M., B., C. G. G., G., A. F. L., Y., C. I., d.S., R. A. F., P., Andreae, C., M. O., R. and C.-U., L. | Single-particle characterization of aerosols collected at a remote site in the Amazonian rainforest and an urban site in Manaus, Brazil [BibTeX] |
2019 | Atmospheric Chemistry and Physics Vol. 19(2), pp. 1221-1240 |
article | DOI |
BibTeX:
@article{wu_single-particle_2019, author = {Wu, Li, X., Kim, H. K., Geng, H., Godoi, R. H. M., Barbosa, C. G. G., Godoi, A. F. L., Yamamoto, C. I., de Souza, R. A. F., Pöhlker, C., Andreae, M. O., Ro, C.-U., L.}, title = {Single-particle characterization of aerosols collected at a remote site in the Amazonian rainforest and an urban site in Manaus, Brazil}, journal = {Atmospheric Chemistry and Physics}, year = {2019}, volume = {19}, number = {2}, pages = {1221--1240}, doi = {https://doi.org/10.5194/acp-19-1221-2019} } |
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Wu, K., Hayek, M., Restrepo-Coupe, N., Wiedemann, K.T., Xiangtao, XU, Wehr, R., Christoffersen, B.O., Miao, G., da Silva, R., de Araujo, A.C., Oliviera, R.C., Camargo, P.B., Monson, R.K., Huete, A.R., Saleska Scott R., J. and Guan | Partitioning controls on Amazon forest photosynthesis between environmental and biotic factors at hourly to interannual timescales [BibTeX] |
2016 | Global Change Biology, pp. 1365 | article | DOI |
BibTeX:
@article{wu_partitioning_2016, author = {Wu, Kaiyu ; Hayek, Matthew ; Restrepo-Coupe, Natalia ; Wiedemann, Kenia T. ; XU, Xiangtao ; Wehr, Richard ; Christoffersen, Bradley O. ; Miao, Guofang ; da Silva, Rodrigo ; de Araujo, Alessandro C. ; Oliviera, Raimundo C. ; Camargo, Plinio B. ; Monson, Russell K. ; Huete, Alfredo R. ; Saleska, Scott R., Jin ; Guan}, title = {Partitioning controls on Amazon forest photosynthesis between environmental and biotic factors at hourly to interannual timescales}, journal = {Global Change Biology}, year = {2016}, pages = {1365}, doi = {https://doi.org/10.1111/gcb.13509} } |
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Wu, J., Serbin, S.P., Xu, X., Albert, L.P., Chen, M., Meng, R., Saleska, S.R. and Rogers, A. | The phenology of leaf quality and its within-canopy variation are essential for accurate modeling of photosynthesis in tropical evergreen forests [BibTeX] |
2017 | Global Change Biology | article | DOI |
BibTeX:
@article{wu_phenology_2017, author = {Wu, Jin and Serbin, Shawn P. and Xu, Xiangtao and Albert, Loren P. and Chen, Min and Meng, Ran and Saleska, Scott R. and Rogers, Alistair}, title = {The phenology of leaf quality and its within-canopy variation are essential for accurate modeling of photosynthesis in tropical evergreen forests}, journal = {Global Change Biology}, year = {2017}, doi = {https://doi.org/10.1111/gcb.13725} } |
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Wu, J., Rogers, A., Albert, L.P., Ely, K., Prohaska, N., Wolfe, B.T., Oliveira Jr, R.C., Saleska, S.R. and Serbin, S.P. | Leaf reflectance spectroscopy captures variation in carboxylation capacity across species, canopy environment and leaf age in lowland moist tropical forests | 2019 | New Phytologist Vol. 224(2), pp. 663-674 |
article | DOI URL |
Abstract: Summary Understanding the pronounced seasonal and spatial variation in leaf carboxylation capacity (Vc,max) is critical for determining terrestrial carbon cycling in tropical forests. However, an efficient and scalable approach for predicting Vc,max is still lacking. Here the ability of leaf spectroscopy for rapid estimation of Vc,max was tested. Vc,max was estimated using traditional gas exchange methods, and measured reflectance spectra and leaf age in leaves sampled from tropical forests in Panama and Brazil. These data were used to build a model to predict Vc,max from leaf spectra. The results demonstrated that leaf spectroscopy accurately predicts Vc,max of mature leaves in Panamanian tropical forests (R2 = 0.90). However, this single-age model required recalibration when applied to broader leaf demographic classes (i.e. immature leaves). Combined use of spectroscopy models for Vc,max and leaf age enabled construction of the Vc,max–age relationship solely from leaf spectra, which agreed with field observations. This suggests that the spectroscopy technique can capture the seasonal variability in Vc,max, assuming sufficient sampling across diverse species, leaf ages and canopy environments. This finding will aid development of remote sensing approaches that can be used to characterize Vc,max in moist tropical forests and enable an efficient means to parameterize and evaluate terrestrial biosphere models. | |||||
BibTeX:
@article{wu_leaf_2019, author = {Wu, Jin and Rogers, Alistair and Albert, Loren P. and Ely, Kim and Prohaska, Neill and Wolfe, Brett T. and Oliveira Jr, Raimundo Cosme and Saleska, Scott R. and Serbin, Shawn P.}, title = {Leaf reflectance spectroscopy captures variation in carboxylation capacity across species, canopy environment and leaf age in lowland moist tropical forests}, journal = {New Phytologist}, year = {2019}, volume = {224}, number = {2}, pages = {663--674}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.16029}, doi = {https://doi.org/10.1111/nph.16029} } |
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Wu, J., Kobayashi, H., Stark, S.C., Meng, R., Guan, K., Tran, N.N., Gao, S., Yang, W., Restrepo-Coupe, N., Miura, T., Oliviera, R.C., Rogers, A., Dye, D.G., Nelson, B.W., Serbin, S.P., Huete, A.R. and Saleska, S.R. | Biological processes dominate seasonality of remotely sensed canopy greenness in an Amazon evergreen forest | 2018 | New Phytologist Vol. 217(4), pp. 1507-1520 |
article | DOI URL |
Abstract: Summary Satellite observations of Amazon forests show seasonal and interannual variations, but the underlying biological processes remain debated. Here we combined radiative transfer models (RTMs) with field observations of Amazon forest leaf and canopy characteristics to test three hypotheses for satellite-observed canopy reflectance seasonality: seasonal changes in leaf area index, in canopy-surface leafless crown fraction and/or in leaf demography. Canopy RTMs (PROSAIL and FLiES), driven by these three factors combined, simulated satellite-observed seasonal patterns well, explaining c. 70% of the variability in a key reflectance-based vegetation index (MAIAC EVI, which removes artifacts that would otherwise arise from clouds/aerosols and sun–sensor geometry). Leaf area index, leafless crown fraction and leaf demography independently accounted for 1, 33 and 66% of FLiES-simulated EVI seasonality, respectively. These factors also strongly influenced modeled near-infrared (NIR) reflectance, explaining why both modeled and observed EVI, which is especially sensitive to NIR, captures canopy seasonal dynamics well. Our improved analysis of canopy-scale biophysics rules out satellite artifacts as significant causes of satellite-observed seasonal patterns at this site, implying that aggregated phenology explains the larger scale remotely observed patterns. This work significantly reconciles current controversies about satellite-detected Amazon phenology, and improves our use of satellite observations to study climate–phenology relationships in the tropics. | |||||
BibTeX:
@article{wu_biological_2018, author = {Wu, Jin and Kobayashi, Hideki and Stark, Scott C. and Meng, Ran and Guan, Kaiyu and Tran, Ngoc Nguyen and Gao, Sicong and Yang, Wei and Restrepo-Coupe, Natalia and Miura, Tomoaki and Oliviera, Raimundo Cosme and Rogers, Alistair and Dye, Dennis G. and Nelson, Bruce W. and Serbin, Shawn P. and Huete, Alfredo R. and Saleska, Scott R.}, title = {Biological processes dominate seasonality of remotely sensed canopy greenness in an Amazon evergreen forest}, journal = {New Phytologist}, year = {2018}, volume = {217}, number = {4}, pages = {1507--1520}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.14939}, doi = {https://doi.org/10.1111/nph.14939} } |
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Wu, J., Chavana-Bryant, C., Prohaska, N., Serbin, S.P., Guan, K., Albert, L.P., Yang, X., van Leewen, W.J.D., Garnello, A.J., Martins, G., Malhi, Y., Gerard, F., Oliviera, R.C. and Saleska, S.c.R. | Convergence in relationships between leaf traits, spectra and ageacross diverse canopy environments and two contrasting tropical forests [BibTeX] |
2017 | New Phytologist Vol. 214, pp. 1033-1048 |
article | DOI |
BibTeX:
@article{wu_convergence_2017, author = {Wu, J. and Chavana-Bryant, C. and Prohaska, N. and Serbin, S. P. and Guan, K. and Albert, L. P. and Yang, Xi and van Leewen, W. J. D. and Garnello, A. J. and Martins, G. and Malhi, Y. and Gerard, F. and Oliviera, R. C. and Saleska, S cott R.}, title = {Convergence in relationships between leaf traits, spectra and ageacross diverse canopy environments and two contrasting tropical forests}, journal = {New Phytologist}, year = {2017}, volume = {214}, pages = {1033--1048}, doi = {https://doi.org/10.1111/nph.14051} } |
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Wu, J., Chavana-Bryant, C., Prohaska, N., Serbin, S.P., Guan, K., Albert, L.P., Yang, X., van Leeuwen, W.J.D., Garnello, A.J., Martins, G., Malhi, Y., Gerard, F., Oliviera, R.C. and Saleska, S.R. | Convergence in relationships between leaf traits, spectra and age across diverse canopy environments and two contrasting tropical forests [BibTeX] |
2016 | New Phytologist | article | DOI |
BibTeX:
@article{wu_convergence_2016, author = {Wu, Jin and Chavana-Bryant, Cecilia and Prohaska, Neill and Serbin, Shawn P. and Guan, Kaiyu and Albert, Loren P. and Yang, Xi and van Leeuwen, Willem J. D. and Garnello, Anthony John and Martins, Giordane and Malhi, Yadvinder and Gerard, France and Oliviera, Raimundo Cosme and Saleska, Scott R.}, title = {Convergence in relationships between leaf traits, spectra and age across diverse canopy environments and two contrasting tropical forests}, journal = {New Phytologist}, year = {2016}, doi = {https://doi.org/10.1111/nph.14051} } |
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Wu, J., Albert, L.P., Lopes, A.P., Restrepo-Coupe, N., Hayek, M., Wiedemann, K.T., Guan, K., Stark, S.C., Christoffersen, B., Prohaska, N., Tavares, J.V., Marostica, S., Kobayashi, H., Ferreira, M.L., Campos, K.S., Silva, R.d., Brando, P.M., Dye, D.G., Huxman, T.E., Huete, A.R., Nelson, B.W. and Saleska, S.R. | Leaf development and demography explain photosynthetic seasonality in Amazon evergreen forests [BibTeX] |
2016 | Science Vol. 351(6276), pp. 972-976 |
article | |
BibTeX:
@article{wu_leaf_2016, author = {Wu, Jin and Albert, Loren P. and Lopes, Aline P. and Restrepo-Coupe, Natalia and Hayek, Matthew and Wiedemann, Kenia T. and Guan, Kaiyu and Stark, Scott C. and Christoffersen, Bradley and Prohaska, Neill and Tavares, Julia V. and Marostica, Suelen and Kobayashi, Hideki and Ferreira, Mauricio L. and Campos, Kleber Silva and Silva, Rodrigo da and Brando, Paulo M. and Dye, Dennis G. and Huxman, Travis E. and Huete, Alfredo R. and Nelson, Bruce W. and Saleska, Scott R.}, title = {Leaf development and demography explain photosynthetic seasonality in Amazon evergreen forests}, journal = {Science}, year = {2016}, volume = {351}, number = {6276}, pages = {972--976} } |
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Worobiec, A., Szaloki, I., Osan, J., Maenhaut, W., Stefaniak, E.A. and Van Grieken, R. | Characterisation of Amazon Basin aerosols at the individual particle level by X-ray microanalytical techniques | 2007 | Atmospheric Environment Vol. 41(39), pp. 9217-9230 |
article | DOI URL |
Abstract: As a part of the LBA/CLAIRE-98 project (LBA, Large-Scale Biosphere-Atmosphere Experiment in Amazonia; CLAIRE, Cooperative LBA Regional Experiment), an extensive aerosol characterisation study was performed. The field work for the study took place in the Amazon Basin from 23 March to 15 April 1998. The collected aerosol samples were analysed by conventional and thin-window electron probe X-ray microanalysis (EPMA) combined with principal component analysis (PCA). Intensive transport of soil dust particles from the Sahara was observed at the end of March and beginning of April. The absolute number concentration of fine soil dust particles (0.30 mu m textless particle diameter textless 2 mu m) reached a value of 3.5 million m(-3). Changes in the total number of particles and reactions of the Saharan dust, i.e., agglomeration with sea salt above the Atlantic Ocean and with local particulate matter, were observed. Particle number concentrations were higher in the fine size fraction, with soil dust dominating in the first part of the campaign. A significant contribution of natural biogenic particles was observed in the last 2 weeks of the campaign, but only in the coarse size fraction. The organic part of the aerosol particles and their agglomeration with other types of particles was studied. The chemical transformation of airborne marine particles in the abundant presence of gaseous pollutants originating from biomass burning and biogenic emissions was observed as well, e.g. N-containing species such as sodium nitrate particles classified as aged sea salt. Carbon was present in almost all particle types. (C) 2007 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{worobiec_characterisation_2007, author = {Worobiec, Anna and Szaloki, Imre and Osan, Janos and Maenhaut, Willy and Stefaniak, Elzbieta Anna and Van Grieken, Rene}, title = {Characterisation of Amazon Basin aerosols at the individual particle level by X-ray microanalytical techniques}, journal = {Atmospheric Environment}, year = {2007}, volume = {41}, number = {39}, pages = {9217--9230}, url = {://WOS:000252260400031}, doi = {https://doi.org/10.1016/j.atmosenv.2007.07.056} } |
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Womack, A.M., Artaxo, P.E., Ishida, F.Y., Mueller, R.C., Saleska, S.R., Wiedemann, K.T., Bohannan, B.J.M. and Green, J.L. | Characterization of active and total fungal communities in the atmosphere over the Amazon rainforest [BibTeX] |
2015 | Biogeosciences Vol. 12, pp. 6337-6349 |
article | DOI |
BibTeX:
@article{womack_characterization_2015, author = {Womack, A. M. and Artaxo, P. E. and Ishida, F. Y. and Mueller, R. C. and Saleska, S. R. and Wiedemann, K. T. and Bohannan, B. J. M. and Green, J. L.}, title = {Characterization of active and total fungal communities in the atmosphere over the Amazon rainforest}, journal = {Biogeosciences}, year = {2015}, volume = {12}, pages = {6337--6349}, note = {Edition: http://www.biogeosciences.net/12/6337/2015/bg-12-6337-2015.html}, doi = {https://doi.org/10.5194/bg-12-6337-2015} } |
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Wolff, S.A., Trebs, I., Ocimar, M.A. and Sá, L.D.d.A. | Reactive and non-reactive trace gas exchange within and above an Amazonian rainforest. [BibTeX] |
2013 | Revista Ciência e Natura, pp. 470-472 | article | |
BibTeX:
@article{wolff_reactive_2013, author = {Wolff, S. A. and Trebs, I. and Ocimar, Manzi Antonio and Sá, Leonardo Deane de Abreu}, title = {Reactive and non-reactive trace gas exchange within and above an Amazonian rainforest.}, journal = {Revista Ciência e Natura}, year = {2013}, pages = {470--472} } |
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Wolfarth, N., Tadei, W., Durieux L., B. and Filizola | Epidemiological analysis of malaria and its relationships with hydrological variables in four municipalities of the State of Amazonas, Brazil [BibTeX] |
2013 | Hydrological Sciences Journal Vol. 58, pp. 1-10 |
article | |
BibTeX:
@article{wolfarth_epidemiological_2013, author = {Wolfarth, N.; Tadei, W.P.; Durieux, L., B.R.; Filizola}, title = {Epidemiological analysis of malaria and its relationships with hydrological variables in four municipalities of the State of Amazonas, Brazil}, journal = {Hydrological Sciences Journal}, year = {2013}, volume = {58}, pages = {1--10} } |
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Wittmann, E., Lopes, A., de Oliveira Wittmann, A., Junk, W., Piedade MTF., F. and Householder | Implementation of the Ramsar Convention on South American wetlands: an update [BibTeX] |
2015 | Research and Reports in Biodiversity Studies Vol. 4, pp. 47-58 |
article | |
BibTeX:
@article{wittmann_implementation_2015, author = {Wittmann, E; Lopes, A; de Oliveira Wittmann, A; Junk, WJ; Piedade, MTF., F; Householder}, title = {Implementation of the Ramsar Convention on South American wetlands: an update}, journal = {Research and Reports in Biodiversity Studies}, year = {2015}, volume = {4}, pages = {47--58} } |
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Withey, K., Berenguer, E., Palmeira, A.F., Espırito-Santo, F.D.B., Lennox, G.D., Silva, C.V.J., Aragao, L.E.O.C., Ferreira, J., Franc¸a, F., Malhi, Y., Rossi, L. and Barlow, J. | Quantifying immediate carbon emissions from El Niño-mediated wildfires in humid tropical forests [BibTeX] |
2018 | Phil. Trans. R. Soc. B Vol. 373, pp. 20170312 |
article | DOI |
BibTeX:
@article{withey_quantifying_2018, author = {Withey, K. and Berenguer, E. and Palmeira, A. F. and Espırito-Santo, F. D. B. and Lennox, G. D. and Silva, C. V. J. and Aragao, L. E. O. C. and Ferreira, J. and Franc¸a, F. and Malhi, Y. and Rossi, L.C. and Barlow, J.}, title = {Quantifying immediate carbon emissions from El Niño-mediated wildfires in humid tropical forests}, journal = {Phil. Trans. R. Soc. B}, year = {2018}, volume = {373}, pages = {20170312}, doi = {https://doi.org/10.1098/rstb.2017.0312} } |
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Wimmer, D., Mazon, S.B., Manninen, H.E., Kangasluoma, J., Franchin, A., Nieminen, T., Backman, J., Wang, J., Kuang, C., Krejci, R., Brito, J., Morais, F., Martin, S.T., Artaxo, P., Kulmala, M., Kerminen, V.-M. and Petäjä., T. | Ground-based observation of clusters and nucleationmode particles in the Amazon [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 13245-13264 |
article | |
BibTeX:
@article{wimmer_ground-based_2018, author = {Wimmer, D. and Mazon, S. B. and Manninen, H. E. and Kangasluoma, J. and Franchin, A. and Nieminen, T. and Backman, J. and Wang, J. and Kuang, C. and Krejci, R. and Brito, J. and Morais, F.G. and Martin, S. T. and Artaxo, P. and Kulmala, M. and Kerminen, V.-M. and T., Petäjä.}, title = {Ground-based observation of clusters and nucleationmode particles in the Amazon}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {13245--13264} } |
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Wilson, M., Bates, P., Alsdorf, D., Forsberg, B., Horritt, M., Melack, J., Frappart, F. and Famiglietti, J. | Modeling large-scale inundation of Amazonian seasonally flooded wetlands | 2007 | Geophysical Research Letters Vol. 34(15) |
article | DOI URL |
Abstract: This paper presents the first application and validation of a 2D hydrodynamic model of the Amazon at a large spatial scale. The simulation results suggest that a significantly higher proportion of total flow is routed through the floodplain than previously thought. We use the hydrodynamic model LISFLOOD-FP with topographic data from the Shuttle Radar Topography Mission to predict floodplain inundation for a 240 x 125 km section of the central Amazon floodplain in Brazil and compare our results to satellite- derived estimates of inundation extent, existing gauged data and satellite altimetry. We find that model accuracy is good at high water ( 72% spatial fit; 0.99 m root mean square error in water stage heights), while accuracy drops at low water ( 23%; 3.17 m) due to incomplete drainage of the floodplain resulting from errors in topographic data and omission of floodplain hydrologic processes from this initial model. | |||||
BibTeX:
@article{wilson_modeling_2007, author = {Wilson, Matthew and Bates, Paul and Alsdorf, Doug and Forsberg, Bruce and Horritt, Matthew and Melack, John and Frappart, Frederic and Famiglietti, James}, title = {Modeling large-scale inundation of Amazonian seasonally flooded wetlands}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {15}, url = {://WOS:000248871500004}, doi = {https://doi.org/10.1029/2007gl030156} } |
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Williamson, G.B., Van Eldik, T., Delamonica, P. and Laurance, W.F. | How many millenarians in Amazonia? Sizing the ages of large trees [BibTeX] |
1999 | Trends in Plant Science Vol. 4(10), pp. 387-387 |
article | DOI URL |
BibTeX:
@article{williamson_how_1999, author = {Williamson, G. B. and Van Eldik, T. and Delamonica, P. and Laurance, W. F.}, title = {How many millenarians in Amazonia? Sizing the ages of large trees}, journal = {Trends in Plant Science}, year = {1999}, volume = {4}, number = {10}, pages = {387--387}, url = {://WOS:000082917300006}, doi = {https://doi.org/10.1016/s1360-1385(99)01477-6} } |
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Williamson, G.B., Laurance, W.F., Oliveira, A.A., Delamonica, P., Gascon, C., Lovejoy, T.E. and Pohl, L. | Amazonian tree mortality during the 1997 El Nino drought | 2000 | Conservation Biology Vol. 14(5), pp. 1538-1542 |
article | DOI URL |
Abstract: In 1997, the Amazon Basin experienced an exceptionally severe El Nino drought. We assessed effects of this rare event on mortality rates of trees in intact rainforest based on data from permanent plots. Long-term (5- to 13-year) mortality rates averaged only 1.12% per year prior to the drought. During the drought year, annual mortality jumped to 1.91% but abruptly fell back to 1.23% in the year following El Nino. Trees dying during the drought dirt not differ significantly in site or species composition from those that died previously, and there was no detectable effect of soil texture on mortality rates. These results suggest that intact Amazonian rainforests are relatively resistant to severe El Nino events. | |||||
BibTeX:
@article{williamson_amazonian_2000, author = {Williamson, G. B. and Laurance, W. F. and Oliveira, A. A. and Delamonica, P. and Gascon, C. and Lovejoy, T. E. and Pohl, L.}, title = {Amazonian tree mortality during the 1997 El Nino drought}, journal = {Conservation Biology}, year = {2000}, volume = {14}, number = {5}, pages = {1538--1542}, url = {://WOS:000089816800043 http://onlinelibrary.wiley.com/store/10.1046/j.1523-1739.2000.99298.x/asset/j.1523-1739.2000.99298.x.pdf?v=1&t=h6hwjnyl&s=97b23de2dacb5151bf2106d917c3d6ef9bb7a68e}, doi = {https://doi.org/10.1046/j.1523-1739.2000.99298.x} } |
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Williamson, G.B., Bentos, T., Longworth, J... and Mesquita, R. | Convergence and divergence in alternative successional pathways in Central Amazonia [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 341-348 |
article | |
BibTeX:
@article{williamson_convergence_2014, author = {Williamson, G. B. and Bentos, T.V. and Longworth, J. . and Mesquita, R.C.G.}, title = {Convergence and divergence in alternative successional pathways in Central Amazonia}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {341--348} } |
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Williams, M.R., Filoso, S. and Lefebvre, P. | Effects of land-use change on solute fluxes to floodplain lakes of the central Amazon | 2004 | Biogeochemistry Vol. 68(2), pp. 259-275 |
article | DOI URL |
Abstract: A time-series analysis of airborne photographs and Landsat thematic mapper (TM and ETM+) images and hydrochemical data were used to examine the effects of land-use change from 1930 to 2001 on solute inputs to Lake Calado, a floodplain lake in the central Amazon. Deforestation from slash-and-burn agricultural activities has dramatically decreased the amount of primary growth upland and flooded forests in the basin. The increasing area that is converted to agricultural plots and pasture in the Lake Calado basin has increased solute loading to the lake from upland tributaries (storm and base flow), bank seepage and overland flow, and decreased throughfall inputs. Whereas solute concentrations in stream water were generally higher in 1992 than 1930, Na(+) and Cl(-) concentrations were also considerably higher in 2001 than 1992, likely because of an increase in the number of humans and cattle in the watershed. Estimates of solute inputs to Lake Calado via throughfall indicate that the mass transfer of some major solutes in the throughfall of undisturbed flooded forests can be larger than that from a combination of all other sources in areas that do not have a strong influence from the Solimoes River. Chemical gains in rain as it passed through the forest canopy occurred for most major ions and relatively large gains were observed for PO(4)(3-) and Ca(2+). Although often neglected in studies of tropical forest ecosystems, throughfall can be an important source of solutes to relatively undisturbed lake environments in the central Amazon. | |||||
BibTeX:
@article{williams_effects_2004, author = {Williams, M. R. and Filoso, S. and Lefebvre, P.}, title = {Effects of land-use change on solute fluxes to floodplain lakes of the central Amazon}, journal = {Biogeochemistry}, year = {2004}, volume = {68}, number = {2}, pages = {259--275}, url = {://WOS:000221102500007}, doi = {https://doi.org/10.1023/B:BIOG.0000025746.07774.e0} } |
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Williams, M., Shimabukuro, Y.E., Herbert, D.A., Lacruz, S.P., Renno, C. and Rastetter, E.B. | Heterogeneity of soils and vegetation in an eastern Amazonian rain forest: Implications for scaling up biomass and production | 2002 | Ecosystems Vol. 5(7), pp. 692-704 |
article | DOI URL |
Abstract: Transferring fine-scale ecological knowledge into an understanding of earth system processes presents a considerable challenge to ecologists. Our objective here was to identify and quantify heterogeneity of, and relationships among, vegetation and soil properties in terra firme rain forest ecosystems in eastern Amazonia and assess implications for generating regional predictions of carbon (C) exchange. Some of these properties showed considerable variation among sites; soil textures varied from 11% to 92% clay. But we did not find any significant correlations between soil characteristics (percentage clay, nitrogen [N], C, organic matter) and vegetation characteristics (leaf area index [LAI], foliar N concentration, basal area, biomass, stem density). We found some evidence for increased drought stress on the sandier sites: There was a significant correlation between soil texture and wood delta(13)C (but not with foliar delta(13)C); volumetric soil moisture was lower at sandier sites; and some canopy foliage had large, negative dawn water potentials (psi(id)), indicating limited water availability in the rooting zone. However, at every site at least one foliage sample indicated full or nearly full rehydration, suggesting significant interspecific variability in drought vulnerability. There were significant differences in foliar delta(15) N among sites, but not in foliar % N, suggesting differences in N cycling but not in plant access to N. We used an ecophysiological model to examine the sensitivity of gross primary production (GPP) to observed inter- and intrasite variation in key driving variables-LAI, foliar N, and psi(id). The greatest sensitivity was to foliar N; standard errors on foliar N data translated into uncertainty in GPP predictions up to 10% on sunny days and +/-5% on cloudy days. Local variability in LAI had a minor influence on uncertainty, especially on sunny days. The largest observed reductions in psi(ld) reduced GPP by 4%-6%. If uncertainty in foliar N estimates is propagated into the model, then GPP estimates are not significantly different among sites. Our results suggest that water restrictions in the sandier sites are not enough to reduce production significantly and that texture is not the key control on plant access to N. | |||||
BibTeX:
@article{williams_heterogeneity_2002, author = {Williams, M. and Shimabukuro, Y. E. and Herbert, D. A. and Lacruz, S. P. and Renno, C. and Rastetter, E. B.}, title = {Heterogeneity of soils and vegetation in an eastern Amazonian rain forest: Implications for scaling up biomass and production}, journal = {Ecosystems}, year = {2002}, volume = {5}, number = {7}, pages = {692--704}, url = {://WOS:000179275900009}, doi = {https://doi.org/10.1007/s10021-002-0165-x} } |
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Williams, M., Malhi, Y., Nobre, A.D., Rastetter, E.B., Grace, J. and Pereira, M.G.P. | Seasonal variation in net carbon exchange and evapotranspiration in a Brazilian rain forest: a modelling analysis | 1998 | Plant Cell and Environment Vol. 21(10), pp. 953-968 |
article | DOI URL |
Abstract: Tropical rain forests account for a significant fraction of global net primary productivity, and are important latent energy (LE) sources, affecting extra-tropical atmospheric circulation. The influence of environmental factors on these fluxes has until recently been poorly understood, largely due to a paucity of data, but in recent years the amount of available data has been increased greatly by use of eddy covariance techniques. In this paper we examine the factors that control daily and seasonal carbon (C) and LE fluxes, by comparing a detailed model of the soil-plant-atmosphere continuum against a unique long-term data-set collected using eddy covariance at an undisturbed rain forest site north of Manaus, Brazil. Our initial application of the model was parametrized with simple measurements of canopy structure, and driven with local meteorological data. It made effective predictions of C and LE exchange during the wet season, but dry season predictions were overestimates in both cases. Sensitivity analyses indicated that the best explanation for this behaviour was a seasonal change in soil and root hydraulic resistances (R-b). An optimization routine was then used to estimate the increase in R-b during the dry season that would be required to explain the reduced dry season fluxes. The local soil, a clay latosol, is typical of much of Amazonia, having very low available water and low hydraulic conductivity. We conclude that an increase in soil-root hydraulic resistance in the dry season introduces a significant seasonal cycle to carbon and water fluxes from this tropical forest. Furthermore, our model structure appears to be an effective tool for regional and temporal scaling of C and LE fluxes, with primary data requirements being regional and temporal information on meteorology, leaf area index (LAI), foliar N, critical leaf water potentials, and plant and soil hydraulic characteristics. | |||||
BibTeX:
@article{williams_seasonal_1998, author = {Williams, M. and Malhi, Y. and Nobre, A. D. and Rastetter, E. B. and Grace, J. and Pereira, M. G. P.}, title = {Seasonal variation in net carbon exchange and evapotranspiration in a Brazilian rain forest: a modelling analysis}, journal = {Plant Cell and Environment}, year = {1998}, volume = {21}, number = {10}, pages = {953--968}, url = {://WOS:000077641600001}, doi = {https://doi.org/10.1046/j.1365-3040.1998.00339.x} } |
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Williams, J., Poschl, U., Crutzen, P.J., Hansel, A., Holzinger, R., Warneke, C., Lindinger, W. and Lelieveld, J. | An atmospheric chemistry interpretation of mass scans obtained from a proton transfer mass spectrometer flown over the tropical rainforest of Surinam | 2001 | Journal of Atmospheric Chemistry Vol. 38(2), pp. 133-166 |
article | DOI URL |
Abstract: Data on a variety of organic gases are presented, obtained with a proton transfer mass spectrometer (PTR-MS) operated during the March 1998 LBA/CLAIRE airborne measurement campaign, between 60 and 12500 m over the rainforest in Surinam (2 degrees N-5 degrees N, 54 degrees W-57 degrees W). The instrument can detect molecules with a proton affinity greater than water, including alkenes, dialkenes, carbonyls, alcohols, and nitriles. Many such molecules are emitted from the rainforest (e.g., isoprene) or formed from the oxidation of primary emissions (e.g., methylvinylketone (MVK) and methacrolein (MACR)). From a comparison with modelled data; the variation with altitude; previously reported biogenic emissions and the time and location of the measurement, possible and probable identities for the significant masses encountered in the range 33-140 amu have been deduced. The main observed protonated masses, postulated identities and observed average boundary layer mixing ratios over the rainforest were: 33 methanol (1.1 nmol/mol); 42 acetonitrile (190 pmol/mol); 43 multiple possibilities (5.9 nmol/mol), 45 acetaldehyde (1.7 nmol/mol), 47 formic acid (not quantified); 59 acetone (2.9 nmol/mol), 61 acetic acid (not quantified), 63 dimethyl sulphide (DMS) (289 pmol/mol), 69 isoprene (1.7 nmol/mol), 71 MVK + MACR (1.3 nmol/mol), 73 methyl ethyl ketone (1.8 nmol/mol), 75 hydroxyacetone (606 pmol/mol), 83 C-5 isoprene hydroxy carbonyls C5H8O2, methyl furan, and cis 3-hexen-1-ol (732 pmol/mol), 87 C-5 carbonyls and methacrylic acid, 95 possibly 2-vinyl furan (656 pmol/mol), 97 unknown (305 pmol/mol), 99 cis hexenal (512 pmol/mol) and 101 isoprene C-5 hydroperoxides (575 pmol/mol). Some species agreed well with those derived from an isoprene only photochemical model (e.g., mass 71 MVK + MACR) while others did not and were observed at higher than previously reported mixing ratios (e.g., mass 59 acetone, mass 63 DMS). Monoterpenes were not detected above the detection limit of 300 pmol/mol. Several species postulated are potentially important sources of HOx in the free troposphere, e.g., methanol, acetone, methyl ethyl ketone, methyl vinyl ketone and methacrolein. | |||||
BibTeX:
@article{williams_atmospheric_2001, author = {Williams, J. and Poschl, U. and Crutzen, P. J. and Hansel, A. and Holzinger, R. and Warneke, C. and Lindinger, W. and Lelieveld, J.}, title = {An atmospheric chemistry interpretation of mass scans obtained from a proton transfer mass spectrometer flown over the tropical rainforest of Surinam}, journal = {Journal of Atmospheric Chemistry}, year = {2001}, volume = {38}, number = {2}, pages = {133--166}, url = {://WOS:000166865500002 http://www.springerlink.com/content/v26n6440307112k1/fulltext.pdf}, doi = {https://doi.org/10.1023/a:1006322701523} } |
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Williams, J., Keßel, S.U., Nölscher, A.C., Yang, Y., Lee, Y., Yanez-Serrano, A.M., Wolff, S., Kesselmeier, J., Klüpfel, T., Lelieveld, J. and Shao, M. | Opposite OH reactivity and ozone cycles in the Amazon rainforest and megacity Beijing: Subversion of biospheric oxidant control by anthropogenic emissions [BibTeX] |
2016 | Atmospheric Environment Vol. 125, pp. 112 118 |
article | |
BibTeX:
@article{williams_opposite_2016, author = {Williams, Jonathan and Keßel, Stephan U. and Nölscher, Anke C. and Yang, Yudong and Lee, Yue and Yanez-Serrano, Ana Maria and Wolff, Stefan and Kesselmeier, Jürgen and Klüpfel, Thomas and Lelieveld, Jos and Shao, Min}, title = {Opposite OH reactivity and ozone cycles in the Amazon rainforest and megacity Beijing: Subversion of biospheric oxidant control by anthropogenic emissions}, journal = {Atmospheric Environment}, year = {2016}, volume = {125}, pages = {112 118} } |
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Williams, J., Fischer, H., Harris, G.W., Crutzen, P.J., Hoor, P., Hansel, A., Holzinger, R., Warneke, C., Lindinger, W., Scheeren, B. and Lelieveld, J. | Variability-lifetime relationship for organic trace gases: A novel aid to compound identification and estimation of HO concentrations | 2000 | Journal of Geophysical Research-Atmospheres Vol. 105(D16), pp. 20473-20486 |
article | DOI URL |
Abstract: In this study we report aircraft-borne measurements of organic species made during March 1998 in Surinam, an unpolluted region on the northeast coast of South America Measurements included the following: CO by tunable diode laser; a wide variety of organics including acetone, acetonitrile, and isoprene by proton transfer mass spectrometry (PTR-MS); and nonmethane hydrocarbon measurements by gas chromatography-flame ionization detection. Here we compare the standard deviation of the natural logarithm of the mixing ratio (Sigma_1nX) to the estimated lifetime of these species. This relationship has been used to support identification of masses measured by the PTR-MS; ascertain the consistency and quality of hydrocarbon measurement data; and to provide information concerning sinks of important trace species. A selection of the data is used to indirectly determine an average HO concentration of 2.0 X 10(5) molecules cm(-3) along the back trajectory for air encountered during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia-Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE) measurement campaign between 0-1 km over the tropical rain forest. The lower than expected HO concentration derived could have been caused by significant atmospheric or oceanic photochemical production of acetone and MEK along the back trajectory. | |||||
BibTeX:
@article{williams_variability-lifetime_2000, author = {Williams, J. and Fischer, H. and Harris, G. W. and Crutzen, P. J. and Hoor, P. and Hansel, A. and Holzinger, R. and Warneke, C. and Lindinger, W. and Scheeren, B. and Lelieveld, J.}, title = {Variability-lifetime relationship for organic trace gases: A novel aid to compound identification and estimation of HO concentrations}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2000}, volume = {105}, number = {D16}, pages = {20473--20486}, url = {://WOS:000089107600003}, doi = {https://doi.org/10.1029/2000jd900203} } |
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Williams, E., Rosenfeld, D., Madden, N., Gerlach, J., Gears, N., Atkinson, L., Dunnemann, N., Frostrom, G., Antonio, M., Biazon, B., Camargo, R., Franca, H., Gomes, A., Lima, M., Machado, R., Manhaes, S., Nachtigall, L., Piva, H., Quintiliano, W., Machado, L., Artaxo, P., Roberts, G., Renno, N., Blakeslee, R., Bailey, J., Boccippio, D., Betts, A., Wolff, D., Roy, B., Halverson, J., Rickenbach, T., Fuentes, J. and Avelino, E. | Contrasting convective regimes over the Amazon: Implications for cloud electrification | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Four distinct meteorological regimes in the Amazon basin have been examined to distinguish the contributions from boundary layer aerosol and convective available potential energy (CAPE) to continental cloud structure and electrification. The lack of distinction in the electrical parameters (peak flash rate, lightning yield per unit rainfall) between aerosol-rich October and aerosol-poor November in the premonsoon regime casts doubt on a primary role for the aerosol in enhancing cloud electrification. Evidence for a substantial role for the aerosol in suppressing warm rain coalescence is identified in the most highly polluted period in early October. The electrical activity in this stage is qualitatively peculiar. During the easterly and westerly wind regimes of the wet season, the lightning yield per unit of rainfall is positively correlated with the aerosol concentration, but the electrical parameters are also correlated with CAPE, with a similar degree of scatter. Here cause and effect are difficult to establish with available observations. This ambiguity extends to the "green ocean" westerly regime, a distinctly maritime regime over a major continent with minimum aerosol concentration, minimum CAPE, and little if any lightning. | |||||
BibTeX:
@article{williams_contrasting_2002, author = {Williams, E. and Rosenfeld, D. and Madden, N. and Gerlach, J. and Gears, N. and Atkinson, L. and Dunnemann, N. and Frostrom, G. and Antonio, M. and Biazon, B. and Camargo, R. and Franca, H. and Gomes, A. and Lima, M. and Machado, R. and Manhaes, S. and Nachtigall, L. and Piva, H. and Quintiliano, W. and Machado, L. and Artaxo, P. and Roberts, G. and Renno, N. and Blakeslee, R. and Bailey, J. and Boccippio, D. and Betts, A. and Wolff, D. and Roy, B. and Halverson, J. and Rickenbach, T. and Fuentes, J. and Avelino, E.}, title = {Contrasting convective regimes over the Amazon: Implications for cloud electrification}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200056}, doi = {https://doi.org/10.1029/2001jd000380} } |
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Williams, A., Antonia, A.D., Almeida, V.D., Suarez, J.M., Liebmann, F., Malhado, B. and A.C.M., E. | The drought of the century in the Amazon basin: an analysis of the regional variation of rainfall in South America in 1926 [BibTeX] |
2005 | Acta Amazonica Vol. 35(2), pp. 231-238 |
article | |
BibTeX:
@article{williams_drought_2005, author = {Williams, Antonia, A.D., Antonia, V.D., Almeida, J.M., Suarez, F., Liebmann, B., Malhado, A.C.M., E.}, title = {The drought of the century in the Amazon basin: an analysis of the regional variation of rainfall in South America in 1926}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, number = {2}, pages = {231--238} } |
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Laurance, W.F., Fearnside, P.M., Lovejoy, T.E. and Camargo, J.L.C. | An Amazonian Forest and Its Fragments as a Laboratory of Global Change [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 407-440 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_amazonian_2016, author = {William F. Laurance, Philip M. Fearnside, Thomas E. Lovejoy, José L. C. Camargo}, title = {An Amazonian Forest and Its Fragments as a Laboratory of Global Change}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {407--440}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Wiederkehr, N., Gama, F.F., Mura, J., Santos, J., Bispo, P. and Sano, E. | Analysis of the Target Decomposition Technique Attributes and Polarimetric Ratios to Discriminate Land Use and Land Cover Classes of the Tapajós Region [BibTeX] |
2019 | Bulletin of Geodetic Sciences Vol. 25(1), pp. e2019002 |
article | DOI |
BibTeX:
@article{wiederkehr_analysis_2019, author = {Wiederkehr, N.C. and Gama, F. F. and Mura, J.C. and Santos, J.R. and Bispo, P.C. and Sano, E.E.}, title = {Analysis of the Target Decomposition Technique Attributes and Polarimetric Ratios to Discriminate Land Use and Land Cover Classes of the Tapajós Region}, journal = {Bulletin of Geodetic Sciences}, year = {2019}, volume = {25}, number = {1}, pages = {e2019002}, doi = {https://doi.org/10.1590/s1982-21702019000100002} } |
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Wick, B., Veldkamp, E., de Mello, W.Z., Keller, M. and Crill, P. | Nitrous oxide fluxes and nitrogen cycling along a pasture chronosequence in Central Amazonia, Brazil | 2005 | Biogeosciences Vol. 2(2), pp. 175-187 |
article | URL |
Abstract: We studied nitrous oxide (N(2)O) fluxes and soil nitrogen (N) cycling following forest conversion to pasture in the central Amazon near Santarem, Para, Brazil. Two undisturbed forest sites and 27 pasture sites of 0.5 to 60 years were sampled once each during wet and dry seasons. In addition to soil-atmosphere fluxes of N(2)O we measured 27 soil chemical, soil microbiological and soil physical variables. Soil N(2)O fluxes were higher in the wet season than in the dry season. Fluxes of N(2)O from forest soils always exceeded fluxes from pasture soils and showed no consistent trend with pasture age. At our forest sites, nitrate was the dominant form of inorganic N both during wet and dry season. At our pasture sites nitrate generally dominated the inorganic N pools during the wet season and ammonium dominated during the dry season. Net mineralization and nitrification rates displayed large variations. During the dry season net immobilization of N was observed in some pastures. Compared to forest sites, young pasture sites (textless= 2 years) had low microbial biomass N and protease activities. Protease activity and microbial biomass N peaked in pastures of intermediate age (4 to 8 years) followed by consistently lower values in older pasture (10 to 60 years). The C/N ratio of litter was low at the forest sites (similar to 25) and rapidly increased with pasture age reaching values of 60-70 at pastures of 15 years and older. Nitrous oxide emissions at our sites were controlled by C and N availability and soil aeration. Fluxes of N2O were negatively correlated to leaf litter C/N ratio, NH(4)(+)-N and the ratio of NO(3)(-)-N to the sum of NO(3)(-)-N + NH(4)(+)-N (indicators of N availability), and methane fluxes and bulk density (indicators of soil aeration status) during the wet season. During the dry season fluxes of N(2)O were positively correlated to microbial biomass N, beta-glucosidase activity, total inorganic N stocks and NH(4)(+)-N. In our study region, pastures of all age emitted less N(2)O than old-growth forests, because of a progressive decline in N availability with pasture age combined with strongly anaerobic conditions in some pastures during the wet season. | |||||
BibTeX:
@article{wick_nitrous_2005, author = {Wick, B. and Veldkamp, E. and de Mello, W. Z. and Keller, M. and Crill, P.}, title = {Nitrous oxide fluxes and nitrogen cycling along a pasture chronosequence in Central Amazonia, Brazil}, journal = {Biogeosciences}, year = {2005}, volume = {2}, number = {2}, pages = {175--187}, url = {://WOS:000236195000006} } |
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Whitehead, J.D., Darbyshire, E., Brito, J., Barbosa, H.M.J., Crawford, I., Stern, R., Gallagher, M.W., Kaye, P.H., Allan, J.D., Coe, H., Artaxo, P. and McFiggans., G. | Biogenic cloud nuclei in the central Amazon during the transition from wet to dry season [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 9727-9743 |
article | DOI |
BibTeX:
@article{whitehead_biogenic_2016, author = {Whitehead, J. D. and Darbyshire, E. and Brito, J. and Barbosa, H. M. J. and Crawford, I. and Stern, R. and Gallagher, M. W. and Kaye, P. H. and Allan, J. D. and Coe, H. and Artaxo, P. and G., McFiggans.}, title = {Biogenic cloud nuclei in the central Amazon during the transition from wet to dry season}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {9727--9743}, doi = {https://doi.org/10.5194/acp-16-9727-2016} } |
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Werth, D. and Avissar, R. | The regional evapotranspiration of the Amazon | 2004 | Journal of Hydrometeorology Vol. 5(1), pp. 100-109 |
article | DOI URL |
Abstract: The annual cycle of evapotranspiration (ET) is an important component of the Amazon hydrological balance, which is of critical importance to the global water cycle. Understanding the changing water balance in this region is particularly important to estimate future global and regional hydroclimate change in response to projected deforestation of the rain forest in this region. Several methods have been used to estimate the annual ET cycle in the Amazon basin. These different methods, which result in a spread of annual means, ranges, and phases of the ET cycle, are evaluated here. In an attempt to reconcile the differences between them, both the data and the assumptions upon which the methods are based are scrutinized. The differences seem to originate from the geographic site where radiation and ET are simulated and/or observed and, more significantly, from the way that vegetation controls ET in the different models being used. While field campaigns conducted during the Large-Scale Biosphere Atmosphere (LBA) experiment in the Amazon have provided many new insights into the Amazon hydroclimate, additional observations of ET and precipitation in that region are needed to understand better the processes involved. | |||||
BibTeX:
@article{werth_regional_2004, author = {Werth, D. and Avissar, R.}, title = {The regional evapotranspiration of the Amazon}, journal = {Journal of Hydrometeorology}, year = {2004}, volume = {5}, number = {1}, pages = {100--109}, url = {://WOS:000189076700007}, doi = {https://doi.org/10.1175/1525-7541(2004)005%3C0100:treota%3E2.0.co;2} } |
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Werth, D. and Avissar, R. | The local and global effects of Amazon deforestation | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: To quantify the effects of land cover changes in the Amazon on local and global climate, numerical simulation experiments using the Goddard Institute for Space Studies Model II global climate model are conducted. An ensemble approach is adopted, in which a group of six control simulations is compared with a group of six deforested simulations. The deforestation effect in the Amazon is strong, with reductions in precipitation, evapotranspiration, and cloudiness. We also detect a noticeable impact in several other regions of the world, several of which show a reduction in rainy season precipitation that exhibits a high signal-to-noise ratio (determined by the t statistic). To determine the significance of the deforestation signal, we create several "false" ensembles, combining control and deforested members randomly, for comparison with the actual "true" ensemble. Such an analysis has not been used previously in deforestation studies and is useful for verifying the significance of a purported effect. The globally averaged precipitation deficits for the true ensemble are generally high in comparison with the false ensembles. Furthermore, changes in the Amazon due to the deforestation correlate significantly with remote changes in several areas. This suggests that the Amazon deforestation is producing a detectable signal throughout the Earth, and this finding underscores the importance of human activity in that region. | |||||
BibTeX:
@article{werth_local_2002, author = {Werth, D. and Avissar, R.}, title = {The local and global effects of Amazon deforestation}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200096}, doi = {https://doi.org/10.1029/2001jd000717} } |
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Wendisch, U. Poschl, M. Andreae, L. Machado, R. Albrecht, H. Schlager, D. Rosenfeld, S. Martin, A. Abdelmonem, A. Afchine, A. Araujo, P. Artaxo, H., M. and Aufmhoff, S. Borrmann, R. Braga, B. Buchholz, M. Cecchini, A. Costa, J. Curtius, M. Dollner, M. Dorf, V. Dreiling, V. Ebert, A. Ehrlich, F. Ewald, , H. Barbosa and G. Fisch, F. Frank, D. Fuetterer, C. Heckl, F. Heidelberg, T. Hueneke, E. Jaekel, E. Jaervinen, T. Jurkat, S. Kanter, U. Kaestner, M. Kenntner, J., A. Fix and Kesselmeier, M. Knecht, R. Kohl, T. Koelling, M. Kraemer, M. Krueger, T. Krisna, J. Lavric, K. Longo, C. Mahnke, A. Manzi, B. Mayer, S., T. Klimach and Mertes, S. Molleker, S. Muench, B. Nillius, K. Pfeilsticker, C. Poehlker, A. Roiger, D. Rose, D. Rosenow, D. Sauer, M. Schnaiter, J. Schneider, C. Schulz, , A. Minikin and R. de Souza, P. Stock, D. Vila, C. Voigt, A. Walser, D. Walter, R. Weigel, B. Weinzierl, F. Werner, M. Yamasoe, H. Ziereis, T. Zinner, and M. Zoeger, A. Spanu | The ACRIDICON-CHUVA campaign: Studying tropical deep convective clouds and precipitation over Amazonia using the new German research aircraft HALO [BibTeX] |
2016 | Bulletin of the American Meteorological Society | article | DOI |
BibTeX:
@article{wendisch_acridicon-chuva_2016, author = {Wendisch, U. Poschl, M. Andreae, L. Machado, R. Albrecht, H. Schlager, D. Rosenfeld, S. Martin, A. Abdelmonem, A. Afchine, A. Araujo, P. Artaxo, H., M. and Aufmhoff, S. Borrmann, R. Braga, B. Buchholz, M. Cecchini, A. Costa, J. Curtius, M. Dollner, M. Dorf, V. Dreiling, V. Ebert, A. Ehrlich, F. Ewald, , H. Barbosa and G. Fisch, F. Frank, D. Fuetterer, C. Heckl, F. Heidelberg, T. Hueneke, E. Jaekel, E. Jaervinen, T. Jurkat, S. Kanter, U. Kaestner, M. Kenntner, J., A. Fix and Kesselmeier, M. Knecht, R. Kohl, T. Koelling, M. Kraemer, M. Krueger, T. Krisna, J. Lavric, K. Longo, C. Mahnke, A. Manzi, B. Mayer, S., T. Klimach and Mertes, S. Molleker, S. Muench, B. Nillius, K. Pfeilsticker, C. Poehlker, A. Roiger, D. Rose, D. Rosenow, D. Sauer, M. Schnaiter, J. Schneider, C. Schulz, , A. Minikin and R. de Souza, P. Stock, D. Vila, C. Voigt, A. Walser, D. Walter, R. Weigel, B. Weinzierl, F. Werner, M. Yamasoe, H. Ziereis, T. Zinner, and M. Zoeger, A. Spanu}, title = {The ACRIDICON-CHUVA campaign: Studying tropical deep convective clouds and precipitation over Amazonia using the new German research aircraft HALO}, journal = {Bulletin of the American Meteorological Society}, year = {2016}, doi = {https://doi.org/10.1175/BAMS-D-14-00255.1} } |
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Wei, D., Ruiz-Plancarte, J., Freire, L.S., Gerken, T., Chamecki, M., Fuentes, J.D., Stoy, P., Trowbridge, A., Nascimento dos Santos, M., Acevedo, R.M. and O. Dias, N. | Relationship between canopy turbulence and vertical distribution of reactive gases in the central Amazon rainforest [BibTeX] |
2016 | Ciência & Natura Vol. 38(Ed. Especial- IX Workshop Brasileiro de Micrometeorologia), pp. 543-547 |
article | DOI |
BibTeX:
@article{wei_relationship_2016, author = {Wei, D. and Ruiz-Plancarte, J. and Freire, L. S. and Gerken, T. and Chamecki, M. and Fuentes, J. D. and Stoy, P.C. and Trowbridge, A. and M., Nascimento dos Santos and R.M., Acevedo and O. Dias, N.L.}, title = {Relationship between canopy turbulence and vertical distribution of reactive gases in the central Amazon rainforest}, journal = {Ciência & Natura}, year = {2016}, volume = {38}, number = {Ed. Especial- IX Workshop Brasileiro de Micrometeorologia}, pages = {543--547}, doi = {https://doi.org/10.5902/2179460X20275} } |
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Wei, D., Fuentes, J.D., Gerken, T., Trowbridge, A.M., Stoy, P.C. and Chamecki, M. | Influences of nitrogen oxides and isoprene on ozone-temperature relationships in the Amazon rain forest [BibTeX] |
2019 | Atmospheric Environment Vol. 206, pp. 280-292 |
article | DOI |
BibTeX:
@article{wei_influences_2019, author = {Wei, Dandan and Fuentes, Jose D. and Gerken, Tobias and Trowbridge, Amy M. and Stoy, Paul C. and Chamecki, Marcelo}, title = {Influences of nitrogen oxides and isoprene on ozone-temperature relationships in the Amazon rain forest}, journal = {Atmospheric Environment}, year = {2019}, volume = {206}, pages = {280--292}, doi = {https://doi.org/10.1016/j.atmosenv.2019.02.044} } |
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Wei, D., Fuentes, J.D., Gerken, T., Chamecki, M. and Santos, R.M.N.d. | Environmental and biological controls on seasonal patterns of isoprene above a rain forest in central Amazonia [BibTeX] |
2018 | Agricultural and Forest Meteorology Vol. 256–257, pp. 391-406 |
article | |
BibTeX:
@article{wei_environmental_2018, author = {Wei, D. and Fuentes, J. D. and Gerken, T. and Chamecki, M. and Santos, R. M. N. dos}, title = {Environmental and biological controls on seasonal patterns of isoprene above a rain forest in central Amazonia}, journal = {Agricultural and Forest Meteorology}, year = {2018}, volume = {256–257}, pages = {391--406} } |
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Webler, A.D., Aguiar, R.G. and Aguiar, L.J.G. | Fluxo de Massa e Radiação Fotossinteticamente Ativa em um Área de Pastagem e de Floresta em Rondônia [BibTeX] |
2018 | Vol. 1(1)Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental, pp. 99-105 |
incollection | |
BibTeX:
@incollection{org_fluxo_2018, author = {Webler, A. D. and Aguiar, R. G. and Aguiar, L. J G.}, title = {Fluxo de Massa e Radiação Fotossinteticamente Ativa em um Área de Pastagem e de Floresta em Rondônia}, booktitle = {Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental}, publisher = {Appris Editora}, year = {2018}, volume = {1}, number = {1}, pages = {99--105} } |
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Webler, A.D., Aguiar, R.G. and Aguiar, L.J.G. | Características da precipitação em área de floresta primária e área de pastagem no Estado de Rondônia [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 55-58 |
article | |
BibTeX:
@article{webler_caracteristicas_2007, author = {Webler, Alberto D. and Aguiar, Renata G. and Aguiar, Leonardo J. G.}, title = {Características da precipitação em área de floresta primária e área de pastagem no Estado de Rondônia}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {55--58} } |
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Weber, O.L. and Couto, E.G. | Dinâmica da matéria orgânica no complexo do Pantanal [BibTeX] |
2008 | (463-480)Fundamentos da Matéria Orgânica do Solo: Ecossistemas Tropicais e Subtropicais | incollection | |
BibTeX:
@incollection{metropole_dinamica_2008, author = {Weber, O. L. and Couto, E. G.}, title = {Dinâmica da matéria orgânica no complexo do Pantanal}, booktitle = {Fundamentos da Matéria Orgânica do Solo: Ecossistemas Tropicais e Subtropicais}, year = {2008}, number = {463-480} } |
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Waterloo, M.J., Oliveira, S.M., Drucker, D.P., Nobre, A.D., Cuartas, L.A., Hodnett, M.G., Langedijk, I., Jans, W.W.P., Tomasella, J., de Araujo, A.C., Pimentel, T.P. and Munera Estrada, J.C. | Export of organic carbon in run-off from an Amazonian rainforest blackwater catchment | 2006 | Hydrological Processes Vol. 20(12), pp. 2581-2597 |
article | DOI URL |
Abstract: Rainfall, run-off and dissolved and particulate organic carbon concentrations were measured to investigate the hydrological export of organic carbon out of the blackwater Igarape Asu rainforest catchment over a two-year period. Annual rainfall was above average (2442 mm) at 2976 mm in 2002 and below average at 2054 mm in 2003. Surface run-off dominated the flow out of the catchment, with groundwater outflow being negligible. Streamflow totals amounted to 1362 mm in 2002 and 780 mm in 2003. Dissolved organic carbon (DOC) concentrations in rainfall were similar to those measured in rainfall elsewhere in the Amazon Basin at 1-2 mg l(-1), leading to atmospheric DOC deposition estimates of 3.5 g m(-2) in 2002 and 2.4 g m(-2) in 2003. Daily average DOC concentrations in run-off ranged from 8 mg l(-1) under low flow conditions to 27 mg l(-1) during large quickflow events. Suspended sediment (10-2000-mu m size fraction) consisted for 28% of carbon and had a median concentration of 4.1 mg l(-1). Daily run-off varied between 1.2-2.5 mm day(-1) during dry periods with corresponding organic carbon exports of 0.009-0.031 g m(-2) day(-1). Exports associated with large storms were much higher, reaching a daily maximum of 1.02 g m(-2) day(-1) for a discharge event of 38.4 mm. Export of carbon during the wet seasons amounted to 70% of the total. Annual exports in river water were different between the years because of differences in run-off, varying between 26.2 g C m(-2) in 2002 and 11.7 g C m(-2) in 2003. Organic carbon exports were dominated by DOC, with exports in sediment constituting 6-8% of the total. Net carbon export, corrected for rainfall inputs, amounted to 22.7 and 9.3 g m(-2) in 2002 and 2003, respectively. The present study indicates that accounting for exports of organic carbon in stream runoff (averaging 19.0 g m(-2) year(-1) over the 2 years) would reduce the rainforest sink strength, estimated at 300-400 g m(-2) year(-1) from eddy covariance measurements, by 5-6% for this blackwater catchment. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{waterloo_export_2006, author = {Waterloo, Maarten J. and Oliveira, Sylvia M. and Drucker, Debora P. and Nobre, Antonio D. and Cuartas, Luz A. and Hodnett, Martin G. and Langedijk, Ivar and Jans, Wilma W. P. and Tomasella, Javier and de Araujo, Alessandro C. and Pimentel, Tania P. and Munera Estrada, Juan C.}, title = {Export of organic carbon in run-off from an Amazonian rainforest blackwater catchment}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2581--2597}, url = {://WOS:000239670800008}, doi = {https://doi.org/10.1002/hyp.6217} } |
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Ward, T.S., Sawakuchi, H.O., Gagne-Maynard, W., Cunha, A.C., Brito, D.C., Neu, V., de Matos Valerio, A., da Silva, R., Krusche, A.V., Richey, J.E., Keil Richard G., N.D. and Bianchi | The reactivity of plant-derived organic matter and the potential importance of priming effects along the lower Amazon River [BibTeX] |
2016 | Journal of Geophysical Research-Biogeosciences Vol. 121, pp. 1 |
article | |
BibTeX:
@article{ward_reactivity_2016, author = {Ward, Thomas S. ; Sawakuchi, Henrique O. ; Gagne-Maynard, William ; Cunha, Alan C. ; Brito, Daimio C. ; Neu, Vania ; de Matos Valerio, Aline ; da Silva, Rodrigo ; Krusche, Alex V. ; Richey, Jeffrey E. ; Keil, Richard G., Nicholas D. ; Bianchi}, title = {The reactivity of plant-derived organic matter and the potential importance of priming effects along the lower Amazon River}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2016}, volume = {121}, pages = {1} } |
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Ward, N.D., Krusche, A., Sawakuchi, H., Brito, D., Cunha, A., Moura, J.M.S., Silva, R., Yager, P.L., Keil, R. and Richey, J. | The compositional evolution of dissolved and particulate organic matter along the lower Amazon River-Óbidos to the ocean [BibTeX] |
2015 | Marine Chemistry Vol. 177(2), pp. 244-256 |
article | |
BibTeX:
@article{ward_compositional_2015, author = {Ward, Nicholas D. and Krusche, A.V. and Sawakuchi, H.O. and Brito, D.C. and Cunha, A.C. and Moura, J. M. S. and Silva, R.da and Yager, P. L. and Keil, R.G. and Richey, J.E.}, title = {The compositional evolution of dissolved and particulate organic matter along the lower Amazon River-Óbidos to the ocean}, journal = {Marine Chemistry}, year = {2015}, volume = {177}, number = {2}, pages = {244--256} } |
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Ward, N., Keil, R., Medeiros, P., Brito, D., Cunha, A., Dittmar, T., Yager, P., Krusche, A. and Richey, J. | Degradation of terrestrially derived macromolecules in the Amazon River Nicholas D. [BibTeX] |
2013 | Nature Geoscience Vol. 6, pp. 530-533 |
article | DOI |
BibTeX:
@article{ward_degradation_2013, author = {Ward, ND and Keil, RG and Medeiros, PM and Brito, DC and Cunha, AC and Dittmar, T and Yager, PL and Krusche, AK and Richey, JE}, title = {Degradation of terrestrially derived macromolecules in the Amazon River Nicholas D.}, journal = {Nature Geoscience}, year = {2013}, volume = {6}, pages = {530--533}, doi = {https://doi.org/10.1038/NGEO1817} } |
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Wantzen, K.M., Nunes da Cunha, C., Junk, W.J., Girard, P., Rossetto, O.C., Penha, J.M.F., Couto, E.G., Becker, M., Priante, G.R., Tomas Walfrido, M., Santos, S.A., Marta, J., Domingos, I.T., Sonoda, F., Cunha, C.N., Curvo, M. and Callil, C. | Suggestions for a sustainable management Concept for the Pantanal [BibTeX] |
2011 | THE PANTANAL: Ecology, biodiversity and sustainable management of a large neotropical seasonal wetland, pp. 795-832 | incollection | |
BibTeX:
@incollection{wantzen_suggestions_2011, author = {Wantzen, K. M. and Nunes da Cunha, C. and Junk, W. J. and Girard, P. and Rossetto, O. C. and Penha, J. M. F. and Couto, E. G. and Becker, M. and Priante, G. R. and M., Tomas Walfrido and Santos, S. A. and Marta, J. and Domingos, I. T. and Sonoda, F. and Cunha, C. N. and Curvo, M. and Callil, C.}, title = {Suggestions for a sustainable management Concept for the Pantanal}, booktitle = {THE PANTANAL: Ecology, biodiversity and sustainable management of a large neotropical seasonal wetland}, publisher = {ed.Sofia : Pensoft}, year = {2011}, pages = {795--832} } |
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Wantzen, K., Couto, E., Mund, E. and al. , e. | Soil carbon stocks in stream-valley-ecosystems in the Brazilian Cerrado Agroscape [BibTeX] |
2012 | Agriculture, Ecosystems & Environment Vol. 151, pp. 70-79 |
article | |
BibTeX:
@article{wantzen_soil_2012, author = {Wantzen, K.M. and Couto, E.G. and Mund, E.E. and al., et}, title = {Soil carbon stocks in stream-valley-ecosystems in the Brazilian Cerrado Agroscape}, journal = {Agriculture, Ecosystems & Environment}, year = {2012}, volume = {151}, pages = {70--79} } |
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Wang, X., Wang, Q., Prass, M., Pöhlker, C., Moran-Zuloaga, D., Artaxo, P., Gu, J., Yang, N., Yang, X., Tao, J., Hong, J., Ma, N., Cheng, Y., Su, H. and Andreae, M.O. | The export of African mineral dust across the Atlantic and its impact over the Amazon Basin [BibTeX] |
2022 | Atmos. Chem. Phys. Discuss. Vol. 2022, pp. 1-44 |
article | DOI URL |
BibTeX:
@article{wang_export_2022, author = {Wang, X. and Wang, Q. and Prass, M. and Pöhlker, C. and Moran-Zuloaga, D. and Artaxo, P. and Gu, J. and Yang, N. and Yang, X. and Tao, J. and Hong, J. and Ma, N. and Cheng, Y. and Su, H. and Andreae, M. O.}, title = {The export of African mineral dust across the Atlantic and its impact over the Amazon Basin}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2022}, volume = {2022}, pages = {1--44}, url = {https://acp.copernicus.org/preprints/acp-2022-683/}, doi = {https://doi.org/10.5194/acp-2022-683} } |
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Wang, X., Chen, J.M., Ju, W. and Zhang, Y. | Seasonal Variations in Leaf Maximum Photosynthetic Capacity and Its Dependence on Climate Factors Across Global FLUXNET Sites | 2022 | Journal of Geophysical Research: Biogeosciences Vol. 127(5), pp. e2021JG006709 |
article | DOI URL |
Abstract: Abstract The maximum carboxylation rate (Vcmax) is an important parameter affecting the photosynthesis rate of plant leaves. In terrestrial ecosystem models (TEMs), Vcmax at 25°C (Vm25°) is often assigned as constants according to plant functional types (PFTs), while its variations with leaf temperature and nutrient contents are described using empirical functions. However, Vm25° could itself vary seasonally due to changes in the leaf physiological state that cannot be described by the empirical functions, potentially causing large uncertainties in simulated water and carbon fluxes. So far, the seasonal variation in Vm25° has not been systematically studied. Here, we generated a Vm25° data set of eight main biomes from 2000 to 2020 using eddy covariance (EC) measurements at globally distributed 176 sites. The boreal ecosystem productivity simulator was combined with a light response curve model (BEPS-LRC) to invert Vm25° from EC data. We investigated seasonal variations of Vm25° and analyzed how different environmental and physiological factors, such as physiological (leaf chlorophyll content, LCC and Rubisco or RuBP) and climatic environment factors, including air temperature (Ta), solar shortwave radiation, CO2 concentration (CO2), and soil water content (SWC), influence this parameter. Vm25° values derived from flux data using BEPS-LRC correlate well with Vm25° of the reference data set (R2 = 0.74, slope = 0.77, and root mean square error = 24.45 ?mol m?2 s?1, p textless 0.001). Leaf Vm25° has strong seasonal variations in all PFTs except for in evergreen broadleaf forests, but its seasonal variation patterns differ greatly among eight biomes. Air temperature (Ta) is the most important determinant of Vm25°, followed by SWC. The interactive effects of Ta and SWC on Vm25° vary among different biomes. The seasonal variation of Vm25° was strongly dependent on LCC. After the correction of temperature effect, the contribution of LCC to the seasonal variation of Vm25° averaged 26% among eight biomes. These findings provide useful information for better parameterization of Vm25° in TEMs. | |||||
BibTeX:
@article{wang_seasonal_2022, author = {Wang, Xiaoping and Chen, Jing M. and Ju, Weimin and Zhang, Yongguang}, title = {Seasonal Variations in Leaf Maximum Photosynthetic Capacity and Its Dependence on Climate Factors Across Global FLUXNET Sites}, journal = {Journal of Geophysical Research: Biogeosciences}, year = {2022}, volume = {127}, number = {5}, pages = {e2021JG006709}, url = {https://doi.org/10.1029/2021JG006709}, doi = {https://doi.org/10.1029/2021JG006709} } |
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Wang, W., Kourtchev, I., Graham, B., Cafmeyer, J., Maenhaut, W. and Claeys, M. | Characterization of oxygenated derivatives of isoprene related to 2-methyltetrols in Amazonian aerosols using trimethylsilylation and gas chromatography/ion trap mass spectrometry | 2005 | Rapid Commun Mass Spectrom Vol. 19(10), pp. 1343-51 |
article | DOI URL |
Abstract: In the present study, we have tentatively identified the structures of three oxygenated derivatives of isoprene in Amazonian rain forest aerosols as the C(5) alkene triols, 2-methyl-1,3,4-trihydroxy-1-butene (cis and trans) and 3-methyl-2,3,4-trihydroxy-1-butene. The formation of these oxygenated derivatives of isoprene can be explained by acid-catalyzed ring opening of epoxydiol derivatives of isoprene, namely, 1,2-epoxy-2-methyl-3,4-dihydroxybutane and 1,2-dihydroxy-2-methyl-3,4-epoxybutane. The structural proposals of the C(5) alkene triols were based on chemical derivatization reactions and detailed interpretation of electron and chemical ionization mass spectral data, including data obtained from first-order mass spectra, deuterium labeling of the trimethylsilyl methyl groups, and MS(2) ion trap experiments. The characterization of 2-methyl-1,3,4-trihydroxy-1-butene (cis and trans) and 3-methyl-2,3,4-trihydroxy-1-butene in forest aerosols is important from an atmospheric chemistry viewpoint in that these compounds hint at the formation of intermediate isomeric epoxydiol derivatives of isoprene and as such provide mechanistic insights into the formation of the previously reported 2-methyltetrols through photooxidation of isoprene. | |||||
BibTeX:
@article{wang_characterization_2005, author = {Wang, W. and Kourtchev, I. and Graham, B. and Cafmeyer, J. and Maenhaut, W. and Claeys, M.}, title = {Characterization of oxygenated derivatives of isoprene related to 2-methyltetrols in Amazonian aerosols using trimethylsilylation and gas chromatography/ion trap mass spectrometry}, journal = {Rapid Commun Mass Spectrom}, year = {2005}, volume = {19}, number = {10}, pages = {1343--51}, note = {Edition: 2005/04/28}, url = {http://www.ncbi.nlm.nih.gov/pubmed/15856536 http://onlinelibrary.wiley.com/store/10.1002/rcm.1940/asset/1940_ftp.pdf?v=1&t=h6hwulpu&s=7562605b2435ad563035881949d45c7cf4bb2154}, doi = {https://doi.org/10.1002/rcm.1940} } |
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Wang, Q., Saturno, J., Chi, X., Walter, D., Lavric, J., Moran-Zuloaga, D., Ditas, F., Pöhlker, C., Brito, J., Carbone, S., Artaxo, P. and Andreae, M.O. | Modeling investigation of light absorbing aerosols in the central Amazon during the wet season [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 14775-14794 |
article | DOI |
BibTeX:
@article{wang_modeling_2016, author = {Wang, Q. and Saturno, J. and Chi, X. and Walter, D. and Lavric, J.V. and Moran- Zuloaga, D. and Ditas, F. and Pöhlker, C. and Brito, J. and Carbone, S. and Artaxo, P. and Andreae, M. O.}, title = {Modeling investigation of light absorbing aerosols in the central Amazon during the wet season}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {14775--14794}, doi = {https://doi.org/10.5194/acp-2016-586} } |
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Wang, J. and Krejci, R. and Scott Giangrande, Henrique M. J. Barbosa, Joel Brito, Samara Carbone, Xuguang Chi, Jennifer Comstock, Florian Ditas, Jost Lavric, Hanna E. Manninen, Fan Mei, Daniel Moran-Zuloaga, Christopher Pöhlker, Mira L. Pöhlker, Jorge Saturno, Beat Schmid, Rodrigo A. F. Souza, Stephen R. Springston, Jason M. Tomlinson, Tami Toto, David Walter, Daniela Wimmer, James N. Smith, Markku Kulmala, Luiz A. T. Machado, Paulo Artaxo, Meinrat O. Andreae, Tuukka Petäjä & Scot T. Martin, Chongai Kuang | Amazon boundary layer aerosol concentration sustained by vertical transport during rainfall [BibTeX] |
2016 | Nature | article | DOI |
BibTeX:
@article{wang_amazon_2016, author = {Wang, J. and Krejci, R. and Scott Giangrande, Henrique M. J. Barbosa, Joel Brito, Samara Carbone, Xuguang Chi, Jennifer Comstock, Florian Ditas, Jost Lavric, Hanna E. Manninen, Fan Mei, Daniel Moran-Zuloaga, Christopher Pöhlker, Mira L. Pöhlker, Jorge Saturno, Beat Schmid, Rodrigo A. F. Souza, Stephen R. Springston, Jason M. Tomlinson, Tami Toto, David Walter, Daniela Wimmer, James N. Smith, Markku Kulmala, Luiz A. T. Machado, Paulo Artaxo, Meinrat O. Andreae, Tuukka Petäjä & Scot T. Martin, Chongai Kuang}, title = {Amazon boundary layer aerosol concentration sustained by vertical transport during rainfall}, journal = {Nature}, year = {2016}, doi = {https://doi.org/10.1038/nature19819} } |
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Wang, J., Chagnon, F.J.F., Williams, E.R., Betts, A.K., Renno, N.O., Machado, L.A.T., Bisht, G., Knox, R. and Brase, R.L. | Impact of deforestation in the Amazon basin on cloud climatology | 2009 | Proceedings of the National Academy of Sciences of the United States of America Vol. 106(10), pp. 3670-3674 |
article | DOI URL |
Abstract: Shallow clouds are prone to appear over deforested surfaces whereas deep clouds, much less frequent than shallow clouds, favor forested surfaces. Simultaneous atmospheric soundings at forest and pasture sites during the Rondonian Boundary Layer Experiment (RBLE-3) elucidate the physical mechanisms responsible for the observed correlation between clouds and land cover. We demonstrate that the atmospheric boundary layer over the forested areas is more unstable and characterized by larger values of the convective available potential energy ( CAPE) due to greater humidity than that which is found over the deforested area. The shallow convection over the deforested areas is relatively more active than the deep convection over the forested areas. This greater activity results from a stronger lifting mechanism caused by mesoscale circulations driven by deforestation-induced heterogeneities in land cover. | |||||
BibTeX:
@article{wang_impact_2009, author = {Wang, Jingfeng and Chagnon, Frederic J. F. and Williams, Earle R. and Betts, Alan K. and Renno, Nilton O. and Machado, Luiz A. T. and Bisht, Gautam and Knox, Ryan and Brase, Rafael L.}, title = {Impact of deforestation in the Amazon basin on cloud climatology}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2009}, volume = {106}, number = {10}, pages = {3670--3674}, note = {Edition: 2009/02/25}, url = {://WOS:000264036900008}, doi = {https://doi.org/10.1073/pnas.0810156106} } |
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Wandelli, E. and Fearnside, P. | Secondary vegetation in central Amazonia: Land-use history effects on aboveground biomass [BibTeX] |
2015 | Forest Ecology and Management Vol. 347, pp. 140-148 |
article | |
BibTeX:
@article{wandelli_secondary_2015, author = {Wandelli, E.V. and Fearnside, P.M.}, title = {Secondary vegetation in central Amazonia: Land-use history effects on aboveground biomass}, journal = {Forest Ecology and Management}, year = {2015}, volume = {347}, pages = {140--148} } |
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Walsh, S.J., Messina, J.P., Mena, C.F., Malanson, G.P. and Page, P.H. | Complexity theory, spatial simulation models, and land use dynamics in the Northern Ecuadorian Amazon | 2008 | Geoforum Vol. 39(2), pp. 867-878 |
article | DOI URL |
Abstract: Our research questions and analytical approaches are used to examine coupled human-natural systems in the Northern Ecuadorian Amazon. They are based on complexity theory and extend from our earlier work in Cellular Automata (CA) in which land use/land cover (LULC) change patterns were spatially simulated to examine deforestation and agricultural extensification on household farms. The basic intent is to understand linkages between people and the environment by explicitly considering pattern-process relationships and the nature of feedback mechanisms among social, biophysical, and geographical factors that influence LULC dynamics within the study area. In this research, we describe how our CA modeling approach emphasizes the human dimensions of LULC change by including socio-economic and demographic characteristics at the household-level along with biophysical data that describe the resource endowments of farms, geographic accessibility of farms to roads and communities, and the evolving nature of human-environment interactions over time and space in response to exogenous and endogenous factors. A LULC change scenario is examined by comparing model outcomes generated for a base CA model and an alternative CA model to explore the effects of increases in household income on land use change patterns at the farm level, achieved as a consequence of improved geographic accessibility to roads and communities and increased off-farm employment as a household livelihood strategy. Growth or transitions rules in our CA model, as well as neighborhood associations are sensitive to socio-economic and demographic factors of households, resource endowments of farms, geographic accessibility, and the uncertainty associated with peasant farming in a frontier setting. Model outcomes indicate that increases in household income are associated with more land in pasture and more land being cultivated for crops as a result of greater access to agricultural markets. In addition, more land in secondary forest succession occurs as a consequence of greater access to roads and communities, thereby, affording a better opportunity for off-farm employment and greater levels of household income. (C) 2007 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{walsh_complexity_2008, author = {Walsh, Stephen J. and Messina, Joseph P. and Mena, Carlos F. and Malanson, George P. and Page, Philip H.}, title = {Complexity theory, spatial simulation models, and land use dynamics in the Northern Ecuadorian Amazon}, journal = {Geoforum}, year = {2008}, volume = {39}, number = {2}, pages = {867--878}, url = {://WOS:000254925000031}, doi = {https://doi.org/10.1016/j.geoforum.2007.02.011} } |
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Walker, R., Perz, S., Caldas, M. and Silva, L.G.T. | Land use and land cover change in forest frontiers: The role of household life cycles | 2002 | International Regional Science Review Vol. 25(2), pp. 169-199 |
article | DOI URL |
Abstract: Tropical deforestation remains a critical issue given its present rate and a widespread consensus regarding its implications for the global carbon cycle and biodiversity. Nowhere is the problem more pronounced than in the Amazon basin, home to the world's largest intact, tropical forest. This article addresses land cover change processes at household level in the Amazon basin, and to this end adapts a concept of domestic life cycle to the current institutional environment of tropical frontiers. In particular, it poses a risk minimization model that integrates demography with market-based factors such as transportation costs and accessibility. In essence, the article merges the theory of Chayanov with the household economy framework, in which markets exist for inputs (including labor), outputs, and capital. The risk model is specified and estimated, using survey data for 261 small producers along the Transamazon Highway in the eastern sector of the Brazilian Amazon. | |||||
BibTeX:
@article{walker_land_2002, author = {Walker, R. and Perz, S. and Caldas, M. and Silva, L. G. T.}, title = {Land use and land cover change in forest frontiers: The role of household life cycles}, journal = {International Regional Science Review}, year = {2002}, volume = {25}, number = {2}, pages = {169--199}, url = {://WOS:000176999900002}, doi = {https://doi.org/10.1177/016001760202500202} } |
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Walker, R., Moran, E. and Anselin, L. | Deforestation and cattle ranching in the Brazilian Amazon: External capital and household processes | 2000 | World Development Vol. 28(4), pp. 683-699 |
article | DOI URL |
Abstract: This paper decomposes recent deforestation in four study areas in the Brazilian Amazon into components associated with large ranches and small producers. It then assesses in an inferential framework small producer deforestation with respect to the proximate causes of their farming systems, and the household drivers of their farming system choices. It is shown that, For areas with substantial in-migration of small producers, forest clearance at the household level is mainly attributable to the availability of hired labor, and not to household labor force or the physical capital at their disposal. The paper conducts the inferential analysis of small producer deforestation using measures of forest clearance taken from satellite image classification and directly from field surveys. A substantial discrepancy in the measures is identified, which has implications for household level research on land cover change. (C) 2000 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{walker_deforestation_2000, author = {Walker, R. and Moran, E. and Anselin, L.}, title = {Deforestation and cattle ranching in the Brazilian Amazon: External capital and household processes}, journal = {World Development}, year = {2000}, volume = {28}, number = {4}, pages = {683--699}, url = {://WOS:000086161800005}, doi = {https://doi.org/10.1016/s0305-750x(99)00149-7} } |
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Walker, R., Moore, N.J., Arima, E., Perz, S., Simmons, C., Caldas, M., Vergara, D. and Bohrer, C. | Protecting the Amazon with protected areas | 2009 | Proceedings of the National Academy of Sciences of the United States of America Vol. 106(26), pp. 10582-10586 |
article | DOI URL |
Abstract: This article addresses climate-tipping points in the Amazon Basin resulting from deforestation. It applies a regional climate model to assess whether the system of protected areas in Brazil is able to avoid such tipping points, with massive conversion to semiarid vegetation, particularly along the south and southeastern margins of the basin. The regional climate model produces spatially distributed annual rainfall under a variety of external forcing conditions, assuming that all land outside protected areas is deforested. It translates these results into dry season impacts on resident ecosystems and shows that Amazonian dry ecosystems in the southern and southeastern basin do not desiccate appreciably and that extensive areas experience an increase in precipitation. Nor do the moist forests dry out to an excessive amount. Evidently, Brazilian environmental policy has created a sustainable core of protected areas in the Amazon that buffers against potential climate-tipping points and protects the drier ecosystems of the basin. Thus, all efforts should be made to manage them effectively. | |||||
BibTeX:
@article{walker_protecting_2009, author = {Walker, Robert and Moore, Nathan J. and Arima, Eugenio and Perz, Stephen and Simmons, Cynthia and Caldas, Marcellus and Vergara, Dante and Bohrer, Claudio}, title = {Protecting the Amazon with protected areas}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2009}, volume = {106}, number = {26}, pages = {10582--10586}, note = {Edition: 2009/06/25}, url = {://WOS:000267564300036}, doi = {https://doi.org/10.1073/pnas.0806059106} } |
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Walker, R., Drzyzga, S.A., Li, Y.L., Qi, J.G., Caldas, M., Arima, E. and Vergara, D. | A behavioral model of landscape change in the Amazon Basin: The colonist case | 2004 | Ecological Applications Vol. 14(4), pp. S299-S312 |
article | URL |
Abstract: This paper presents the prototype of a predictive model capable of describing both magnitudes of deforestation and its spatial articulation into patterns of forest fragmentation. In a departure from other landscape models, it establishes an explicit behavioral foundation for algorithm development, predicated on notions of the peasant economy and on household production theory. It takes a "bottom-up" approach, generating the process of land-cover change occurring at lot level together with the geography of a transportation system to describe regional landscape change. In other words, it translates the decentralized decisions of individual households into a collective, spatial impact. In so doing, the model unites the richness of survey research on farm households with the analytical rigor of spatial analysis enabled by geographic information systems (GIS). The paper describes earlier efforts at spatial modeling, provides a critique of the so-called spatially explicit model, and elaborates a behavioral foundation by considering farm practices of colonists in the Amazon basin. It then uses, insight from the behavioral statement to motivate a GIS-based model architecture. The model is implemented for a long-standing colonization frontier in the eastern sector of the basin, along the Trans-Amazon Highway in the State of Para, Brazil. Results are subjected to both sensitivity analysis and error assessment, and suggestions are made about how the model could be improved. | |||||
BibTeX:
@article{walker_behavioral_2004, author = {Walker, R. and Drzyzga, S. A. and Li, Y. L. and Qi, J. G. and Caldas, M. and Arima, E. and Vergara, D.}, title = {A behavioral model of landscape change in the Amazon Basin: The colonist case}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S299--S312}, url = {://WOS:000223269000024} } |
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Walker, R., Diniz, M., Caldas, M. and Chermont, L. | A Economia da Amazônia Hoje e Amanha: Integração Nacional e a Expansão da Oferta [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 117-136 |
incollection | |
BibTeX:
@incollection{batistella_economia_2008, author = {Walker, Robert and Diniz, Marcelo and Caldas, Marcellus and Chermont, Larissa}, title = {A Economia da Amazônia Hoje e Amanha: Integração Nacional e a Expansão da Oferta}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {117--136}, note = {Section: 2} } |
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Walker, R., DeFries, R., Vera-Diaz, M.d.C., Shimabukuro, Y. and Venturieri, A. | The Expansion of Intensive Agriculture and Ranching in Brazilian Amazonia | 2009 | Vol. 186Amazonia and Global Change, pp. 61-82 |
incollection | DOI URL |
Abstract: Agriculture in Amazonia has often provoked controversy, given the tremendous ecological value of the region's environment. First with ranching, and now with the soybean boom, tractors and cattle have marched across lands that for millennia supported only closed moist forest, resident ecosystems, and dispersed indigenous peoples. The present chapter considers this expansion, focusing on the Brazilian portion of the basin. Its premise is that effective Amazonian policy must be grounded on an understanding of the region's agriculture. The chapter pursues its objectives by first addressing the development initiatives that created the preconditions for Amazonia's current agricultural economy. The region is remote and has therefore required sustained government intervention to release its potential. The policy discussion is followed by descriptions of cattle ranching and soy farming. For each, market settings and trajectories of expansion are presented. Although these sectoral descriptions are data rich, they do not provide a conceptual framework for analyzing the environmental impacts of evolving market conditions. To accomplish this, the chapter invokes the classical land use model of von Thunen to explain Amazonian land cover dynamics in relation to soy-cattle linkages. It addresses these dynamics with remote sensing data from Mato Grosso, Para, and Rondonia, and then discusses scenarios of agricultural advances on the forest. Conclusions follow, considering possible policy responses to deforestation, and the social context of agricultural intensification, with special attention to the issues of land tenure security and distributional equity. | |||||
BibTeX:
@incollection{keller_expansion_2009, author = {Walker, R. and DeFries, R. and Vera-Diaz, M. del C. and Shimabukuro, Y. and Venturieri, A.}, title = {The Expansion of Intensive Agriculture and Ranching in Brazilian Amazonia}, booktitle = {Amazonia and Global Change}, year = {2009}, volume = {186}, pages = {61--82}, url = {://WOS:000289443400005}, doi = {https://doi.org/10.1029/2008gm000735} } |
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Walker, R., Browder, J., Arima, E., Simmons, C., Pereira, R., Caldas, M., Shirota, R. and de Zen, S. | Ranching and the new global range: Amazonia in the 21st century | 2009 | Geoforum Vol. 40(5), pp. 732-745 |
article | DOI URL |
Abstract: This paper seeks to understand how the Brazilian Amazon, which many thought unsuitable for agricultural development, has yielded to a dynamic cattle economy in only a few decades. It does so by embedding the Thunian model of location rents within the regime of capital accumulation that has driven the Brazilian economy since the mid-20th century. The paper addresses policies that have created location rents in Amazonia, the effect of these rents on land managers, and the spatial implications of their behavior on forests. Thus, the paper connects macro-processes and structures to agents on the ground, in providing a political ecological explanation relevant to land change science. The policy discussion focuses on reductions in transportation costs. improvements in animal health, and monetary and trade reforms. To illustrate the impact of policy, the paper presents data on the geography of Amazonian herd expansion, on the growth of Amazonian exports, and on the profitability of the region's cattle economy. It follows the empirical presentation with more abstract consideration of the spatial relations between cattle ranching and soy farming, and implications for deforestation. The paper concludes on a speculative note by considering the likelihood of forest transition in the region, given the transformation of Amazonia into a global resource frontier. (C) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{walker_ranching_2009, author = {Walker, Robert and Browder, John and Arima, Eugenio and Simmons, Cynthia and Pereira, Ritaumaria and Caldas, Marcellus and Shirota, Ricardo and de Zen, Sergio}, title = {Ranching and the new global range: Amazonia in the 21st century}, journal = {Geoforum}, year = {2009}, volume = {40}, number = {5}, pages = {732--745}, url = {://WOS:000272789600005}, doi = {https://doi.org/10.1016/j.geoforum.2008.10.009} } |
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Walker, R. and Arima, E. | Smallholder timber sales along the Transamazon Highway: a comment [BibTeX] |
2011 | Ecological Economics Vol. 70(9), pp. 1565-1567 |
article | DOI URL |
BibTeX:
@article{walker_smallholder_2011, author = {Walker, Robert and Arima, Eugenio}, title = {Smallholder timber sales along the Transamazon Highway: a comment}, journal = {Ecological Economics}, year = {2011}, volume = {70}, number = {9}, pages = {1565--1567}, url = {://WOS:000292803300001}, doi = {https://doi.org/10.1016/j.ecolecon.2010.11.018} } |
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Walker, R. | Special issue: Deforestation - Introduction [BibTeX] |
2004 | International Regional Science Review Vol. 27(3), pp. 243-246 |
article | DOI URL |
BibTeX:
@article{walker_special_2004, author = {Walker, R.}, title = {Special issue: Deforestation - Introduction}, journal = {International Regional Science Review}, year = {2004}, volume = {27}, number = {3}, pages = {243--246}, url = {://WOS:000222136600001}, doi = {https://doi.org/10.1177/0160017604266025} } |
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Walker, R. | Theorizing land-cover and land-use change: The case of tropical deforestation | 2004 | International Regional Science Review Vol. 27(3), pp. 247-270 |
article | DOI URL |
Abstract: This article addresses land-cover and land-use dynamics from the perspective of regional science and economic geography. It first provides an account of the so-called spatially explicit model, which has emerged in recent years as a key empirical approach to the issue. The article uses this discussion as a springboard to evaluate the potential utility, of von Thunen to the discourse on land-cover and land-use change. After identifying shortcomings of current theoretical approaches to land use in mainly urban models, the article filters a discussion of deforestation through the lens of bid-rent and assesses its effectiveness in helping us comprehend the destruction of tropical forest in the Amazon basin. The article considers the adjustments that would have to be made to existing theory to make it more useful to the empirical issues. | |||||
BibTeX:
@article{walker_theorizing_2004, author = {Walker, R.}, title = {Theorizing land-cover and land-use change: The case of tropical deforestation}, journal = {International Regional Science Review}, year = {2004}, volume = {27}, number = {3}, pages = {247--270}, url = {://WOS:000222136600002}, doi = {https://doi.org/10.1177/0160017604266026} } |
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Walker, R. | Mapping process to pattern in the landscape change of the Amazonian frontier | 2003 | Annals of the Association of American Geographers Vol. 93(2), pp. 376-398 |
article | DOI URL |
Abstract: Changes in land use and land cover are dynamic processes reflecting a sequence of decisions made by individual land managers. In developing economies, these decisions may be embedded in the evolution of individual households, as is often the case in indigenous areas and agricultural frontiers. One goal of the present article is to address the land-use and land-cover decisions of colonist farmers in the Amazon Basin as a function, in part, of household characteristics. Another goal is to generalize the issue of tropical deforestation into a broader discussion on forest dynamics. The extent of secondary forest in tropical areas has been well documented in South America and Africa. Agricultural-plot abandonment often occurs in tandem with primary forest clearance and as part of the same decision-making calculus. Consequently, tropical deforestation and forest succession are not independent processes in the landscape. This article presents a framework that integrates them into a model of forest dynamics at household level, and in so doing provides an account of the spatial pattern of deforestation that has been observed in the Amazon's colonization frontiers. | |||||
BibTeX:
@article{walker_mapping_2003, author = {Walker, R.}, title = {Mapping process to pattern in the landscape change of the Amazonian frontier}, journal = {Annals of the Association of American Geographers}, year = {2003}, volume = {93}, number = {2}, pages = {376--398}, url = {://WOS:000184143400008}, doi = {https://doi.org/10.1111/1467-8306.9302008} } |
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Wagner, F., Hérault, B., Rossi, V., Hilker, T., Maeda, E., Sanchez, A. and al. , e. | Climate drivers of the Amazon forest greening [BibTeX] |
2017 | PLos ONE Vol. 12(7), pp. e0180932 |
article | DOI |
BibTeX:
@article{wagner_climate_2017, author = {Wagner, F.H. and Hérault, B. and Rossi, V. and Hilker, T. and Maeda, E.E. and Sanchez, A. and al., et}, title = {Climate drivers of the Amazon forest greening}, journal = {PLos ONE}, year = {2017}, volume = {12}, number = {7}, pages = {e0180932}, doi = {https://doi.org/10.1371/journal.pone.0180932} } |
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Wagner, Hérault, B., Bonal, D., Stahl, C., Anderson, L. O., Baker, T. R., Becker, G. S., Beeckman, H., Boanerges Souza, D., Botosso, P. C., Bowman, D. M. J. S., Bräuning, A., Brede, B., Brown, F. I., Camarero, J. J., Camargo, P. B., Cardoso, F. C. G., Carvalho, F. A., Castro, W., Chagas, R. K., Chave, J., Chidumayo, E. N., Clark, D. A., Costa, F. R. C., Couralet, C., da Silva Mauricio, P. H., Dalitz, H., de Castro, V. R., de Freitas Milani, J. E., de Oliveira, E. C., de Souza Arruda, L., Devineau, J.-L., Drew, D. M., Dünisch, O., Durigan, G., Elifuraha, E., Fedele, M., Ferreira Fedele, L., Figueiredo Filho, A., Finger, C. A. G., Franco, A. C., Freitas Júnior, J. L., Galvão, F., Gebrekirstos, A., Gliniars, R., Graça, P. M. L. D. A., Griffiths, A. D., Grogan, J., Guan, K., Homeier, J., Kanieski, M. R., Kho, L. K., Koenig, J., Kohler, S. V., Krepkowski, J., Lemos-Filho, J. P., Lieberman, D., Lieberman, M. E., Lisi, C. S., Longhi Santos, T., López Ayala, J. L., Maeda, E. E., Malhi, Y., Maria, V. R. B., Marques, M. C. M., Marques, R., Maza Chamba, H., Mbwambo, L., Melgaço, K. L. L., Mendivelso, H. A., Murphy, B. P., O'Brien, J. J., Oberbauer, S. F., Okada, N., Pélissier, R., Prior, L. D., Roig, F. A., Ross, M., Rossatto, D. R., Rossi, V., Rowland, L., Rutishauser, E., Santana, H., Schulze, M., Selhorst, D., Silva, W. R., Silveira, M., Spannl, S., Swaine, M. D., Toledo, J. J., Toledo, M. M., Toledo, M., Toma, T., Tomazello Filho, M., Valdez Hernández, J. I., Verbesselt, J., Vieira, S. A., Vincent, G., Volkmer de Castilho, C., Volland, F., Worbes, M., Zanon, M. L. B., and Aragão, L. E. O. C., F. H. | Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests [BibTeX] |
2016 | Biogeosciences Vol. 13, pp. 2537-2562 |
article | DOI |
BibTeX:
@article{wagner_climate_2016, author = {Wagner, Hérault, B., Bonal, D., Stahl, C., Anderson, L. O., Baker, T. R., Becker, G. S., Beeckman, H., Boanerges Souza, D., Botosso, P. C., Bowman, D. M. J. S., Bräuning, A., Brede, B., Brown, F. I., Camarero, J. J., Camargo, P. B., Cardoso, F. C. G., Carvalho, F. A., Castro, W., Chagas, R. K., Chave, J., Chidumayo, E. N., Clark, D. A., Costa, F. R. C., Couralet, C., da Silva Mauricio, P. H., Dalitz, H., de Castro, V. R., de Freitas Milani, J. E., de Oliveira, E. C., de Souza Arruda, L., Devineau, J.-L., Drew, D. M., Dünisch, O., Durigan, G., Elifuraha, E., Fedele, M., Ferreira Fedele, L., Figueiredo Filho, A., Finger, C. A. G., Franco, A. C., Freitas Júnior, J. L., Galvão, F., Gebrekirstos, A., Gliniars, R., Graça, P. M. L. D. A., Griffiths, A. D., Grogan, J., Guan, K., Homeier, J., Kanieski, M. R., Kho, L. K., Koenig, J., Kohler, S. V., Krepkowski, J., Lemos-Filho, J. P., Lieberman, D., Lieberman, M. E., Lisi, C. S., Longhi Santos, T., López Ayala, J. L., Maeda, E. E., Malhi, Y., Maria, V. R. B., Marques, M. C. M., Marques, R., Maza Chamba, H., Mbwambo, L., Melgaço, K. L. L., Mendivelso, H. A., Murphy, B. P., O'Brien, J. J., Oberbauer, S. F., Okada, N., Pélissier, R., Prior, L. D., Roig, F. A., Ross, M., Rossatto, D. R., Rossi, V., Rowland, L., Rutishauser, E., Santana, H., Schulze, M., Selhorst, D., Silva, W. R., Silveira, M., Spannl, S., Swaine, M. D., Toledo, J. J., Toledo, M. M., Toledo, M., Toma, T., Tomazello Filho, M., Valdez Hernández, J. I., Verbesselt, J., Vieira, S. A., Vincent, G., Volkmer de Castilho, C., Volland, F., Worbes, M., Zanon, M. L. B., and Aragão, L. E. O. C., F. H.}, title = {Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests}, journal = {Biogeosciences}, year = {2016}, volume = {13}, pages = {2537--2562}, doi = {https://doi.org/10.5194/bg-13-2537-2016} } |
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Wade, L. | A pristine Amazon's last stand [BibTeX] |
2015 | Science Vol. 347(6226), pp. 1051-1052 |
article | DOI |
BibTeX:
@article{wade_pristine_2015, author = {Wade, L.}, title = {A pristine Amazon's last stand}, journal = {Science}, year = {2015}, volume = {347}, number = {6226}, pages = {1051--1052}, doi = {https://doi.org/10.1126/science.347.6226.1051} } |
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Vourlitis, G.L., Priante, N., Hayashi, M.M.S., Nogueira, J.D., Raiter, F., Hoegel, W. and Campelo, J.H. | Effects of meteorological variations on the CO2 exchange of a Brazilian transitional tropical forest | 2004 | Ecological Applications Vol. 14(4), pp. S89-S100 |
article | URL |
Abstract: The net ecosystem CO2 exchange (NEE) of a 28-30 m tall transitional (eco-tonal) tropical forest of the Brazilian Amazon was quantified using tower-based eddy co-variance. Measurements were made between August 1999 and July 2001 and were used to develop nonlinear statistical models to assess daily variations in ecophysiological parameters and provide annual estimates of NEE, gross ecosystem CO2 exchange (GEE), and respiration (R-e). Diurnal trends in NEE were correlated with variations in photosynthetic photon flux density (Q), vapor pressure deficit (V), and temperature. Seasonal trends in the CO2-flux components estimated from nonlinear regression (A(max) and R-0) were highly correlated with soil water availability and canopy structural properties (LAI and litter production). These results suggest that variations in soil water content can affect rates of canopy photosynthesis and whole forest respiration by altering both physiological processes and canopy structural properties. Estimates of the annual NEE suggest that the forest was in balance with respect to CO2 during the study period, which, in terms of rainfall, was a relatively typical period compared to the 30-yr average rainfall regime. Our results also suggest that the warmer and dryer microclimate and decline in LAI that accompany landcover change will cause transitional forests to be sources Of CO2 to the atmosphere. | |||||
BibTeX:
@article{vourlitis_effects_2004, author = {Vourlitis, G. L. and Priante, N. and Hayashi, M. M. S. and Nogueira, J. D. and Raiter, F. and Hoegel, W. and Campelo, J. H.}, title = {Effects of meteorological variations on the CO2 exchange of a Brazilian transitional tropical forest}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S89--S100}, url = {://WOS:000223269000009} } |
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Vourlitis, G.L., Priante, N., Hayashi, M.M.S., Nogueira, J.D., Caseiro, F.T. and Campelo, J.H. | Seasonal variations in the evapotranspiration of a transitional tropical forest of Mato Grosso, Brazil | 2002 | Water Resources Research Vol. 38(6) |
article | DOI URL |
Abstract: [1] The seasonal pattern of evapotranspiration (expressed as latent heat flux Q(e)) for a 28- to 30-m-tall tropical transitional (ecotonal) forest was quantified over an annual cycle using eddy covariance measurement and micrometeorological estimation techniques. The study was conducted near the city of Sinop, in northern Mato Grosso, Brazil, which is located within the ecotone of tropical rain forest and savanna (cerrado). Although the majority of net radiation (Q*) was consumed by Q(e) (50-90%), seasonal variations in Q(e) were large and positively correlated with precipitation. Total daily Qe for the dry season (June-August) was on average 6.0 MJ m(-2) d(-1), while daily Q(e) for the transition (October-November and April-May) and wet (December-March) season periods were 7.5 and 10.0 MJ m(-2) d(-1), respectively. The seasonal variation in midday (0900-1500 LT) surface conductance (g(s)) was also positively correlated with precipitation. Analysis of the "decoupling factor'' (Omega) indicated that the forest was strongly coupled to the atmosphere (Omega = 0.1-0.3) over the dry season and transition periods, suggesting that Q(e) was under relatively strong stomatal control. Although rainfall during the study period was above the long-term (30-year) average, our results indicate that the seasonal dynamics of Q(e) for the tropical transitional forest were more comparable to tropical savanna than to rain forest. | |||||
BibTeX:
@article{vourlitis_seasonal_2002, author = {Vourlitis, G. L. and Priante, N. and Hayashi, M. M. S. and Nogueira, J. D. and Caseiro, F. T. and Campelo, J. H.}, title = {Seasonal variations in the evapotranspiration of a transitional tropical forest of Mato Grosso, Brazil}, journal = {Water Resources Research}, year = {2002}, volume = {38}, number = {6}, url = {://WOS:000178936000002}, doi = {https://doi.org/10.1029/2000wr000122} } |
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Vourlitis, G.L., Priante, N., Hayashi, M.M.S., Nogueira, J.D., Caseiro, F.T. and Campelo, J.H. | Seasonal variations in the net ecosystem CO2 exchange of a mature Amazonian transitional tropical forest (cerradao) | 2001 | Functional Ecology Vol. 15(3), pp. 388-395 |
article | DOI URL |
Abstract: 1. Tower-based eddy covariance and measurements of the vertical CO2 concentration gradient within the canopy were used to quantify the seasonal variations in the net ecosystem CO2 exchange (NEE) of a 28-30 m tall transitional tropical forest (cerradao). The study was conducted near the city of Sinop, Mato Grosso, Brazil (11 degrees 24.75' S; 55 degrees 19.50' W), which is located in the ecotone of two major regional ecosystem types of South America (tropical rainforest and savanna). 2. The NEE during the dry season (August-September) was in balance, but during the transition period between the dry and wet seasons (October-November) the cerradao stand became a net source of 50-150 mmol m(-2) day(-1) CO2 to the atmosphere. Measurements during the wet season (February, April) indicate that the forest was a net sink of between -55 and -102 mmol m(-2) day(-1). 3. The NEE of the transitional tropical forest was more similar to that of tropical rainforest during the wet season, but during the dry season the NEE of the transitional forest was more similar to that reported for tropical savanna. The data suggest that seasonal variations in rainfall have important implications for the seasonal pattern of NEE in cerradao. | |||||
BibTeX:
@article{vourlitis_seasonal_2001, author = {Vourlitis, G. L. and Priante, N. and Hayashi, M. M. S. and Nogueira, J. D. and Caseiro, F. T. and Campelo, J. H.}, title = {Seasonal variations in the net ecosystem CO2 exchange of a mature Amazonian transitional tropical forest (cerradao)}, journal = {Functional Ecology}, year = {2001}, volume = {15}, number = {3}, pages = {388--395}, url = {://WOS:000169131300013}, doi = {https://doi.org/10.1046/j.1365-2435.2001.00535.x} } |
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Vourlitis, G.L., Nogueira, J.d.S., Priante Filho, N., Hoeger, W., Raiter, F., Biudes, M., Arruda, J., Capistrano, V., Brito de Faria, J. and Lobo, F.d.A. | The sensitivity of Diel CO(2) and H(2)O vapor exchange of a tropical transitional forest to seasonal variation in meteorology and water availability | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Measurements of ecosystem gas exchange, meteorology, and hydrology ( rainfall and soil moisture) were used to assess the seasonal patterns of, and controls on, average diel (24 h) net ecosystem CO(2) exchange (NEE), evapotranspiration (E), and bulk canopy water vapor conductance (G(c)) of a tropical transitional (ecotonal) forest in the Brazilian Amazon. Diel trends in E and NEE were almost completely explained by the diel variation in photosynthetic photon flux density (Q(PPFD)), and while the Q(PPFD) response of E varied little over the annual cycle, the Q(PPFD) response of NEE declined substantially during the dry season, and the magnitude of hysteresis in the NEE - Q(PPFD) response increased as well. The magnitude of the residuals for the Q(PPFD) versus NEE response was significantly negatively correlated with total monthly rainfall and surface soil moisture and positively correlated with the maximum daily temperature and atmospheric vapor pressure deficit ( V). Average daily Gc was also significantly correlated with average daily V ( r= - 0.72) and soil moisture (r = 0.62), suggesting strong stomatal control of NEE during drought. However, drought reduced ecosystem CO(2) efflux relatively more than CO(2) assimilation, suggesting that the seasonal variation in NEE was largely driven by seasonal variation in respiration. When compared with other tropical forests, seasonality in NEE was negatively correlated with annual rainfall and positively correlated with dry-season length. The relatively high sensitivity of NEE to seasonal variation in climate and water availability has profound implications for C cycling dynamics under novel climates resulting from climate and/or land-use change in the Amazon basin. | |||||
BibTeX:
@article{vourlitis_sensitivity_2005, author = {Vourlitis, G. L. and Nogueira, J. de S. and Priante Filho, N. and Hoeger, W. and Raiter, F. and Biudes, M.S. and Arruda, J.C. and Capistrano, V.B. and Brito de Faria, J.L. and Lobo, F. de A.}, title = {The sensitivity of Diel CO(2) and H(2)O vapor exchange of a tropical transitional forest to seasonal variation in meteorology and water availability}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241358500001} } |
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Vourlitis, G.L., Nogueira, J.d.S., Lobo, F.d.A., Sendall, K.M., de Paulo, S.R., Dias, C.A.A., Pinto Jr., O.B. and de Andrade, N.L.R. | Energy balance and canopy conductance of a tropical semi-deciduous forest of the southern Amazon Basin | 2008 | Water Resources Research Vol. 44(3) |
article | DOI URL |
Abstract: Deforestation and climate change have the capacity to alter rainfall regimes, water availability, and surface-atmosphere flux of water and energy of tropical forests, especially in ecotonal, semi-deciduous tropical forests of the southern Amazon Basin, which have experienced rapid regional warming and deforestation over the last three decades. To reduce uncertainty regarding current and future energy and water flux, micrometeorological measurements of latent (Q(e)) and sensible heat flux (Q(h)) and canopy conductance (G(c)) were combined with measurements of sap flux density (F(d)) and maximum leaf conductance (g(smax)) to characterize the seasonal controls on mass (H(2)O) and energy exchange of an ecotonal, semi-deciduous forest in northern Mato Grosso, Brazil over the 2005-2006 annual cycle. Average diel patterns and daily rates of energy flux and conductance declined during the dry season; however, the decline in Fd and Qe was smaller and/or more gradual than Gc and gsmax. Weekly averages of transpiration calculated from sap flow measurements during the dry-wet season transition period were positively correlated (r(2) = 0.47; p textless 0.05; n = 11) with estimates of leaf area index (LAI) derived from the Modis-Aqua satellite platform while estimates of evapotranspiration ET derived from eddy covariance were not, presumably because these estimates also include an evaporation component. Overall, our results suggest that access to deep water reserves can support high rates of Fd and Qe during the dry season, but because of high evaporative demand, declines in plant water potential lead to a corresponding decline in Gc. Furthermore, seasonal variations in LAI, that are likely to be controlled in part by plant water status and phenology, constrain tree and stand transpiration. Thus the consistency of Qe over the annual cycle appears to be the result of trade-offs between water availability (rainfall, soil moisture, water potential), canopy structural properties (LAI), and meteorological conditions including vapor pressure deficit and net radiation. | |||||
BibTeX:
@article{vourlitis_energy_2008, author = {Vourlitis, George L. and Nogueira, Jose de Souza and Lobo, Francisco de Almeida and Sendall, Kerrie M. and de Paulo, Sergio Roberto and Dias, Carlos Alberto Antunes and Pinto, Jr., Osvaldo Borges and de Andrade, Nara Luisa Reis}, title = {Energy balance and canopy conductance of a tropical semi-deciduous forest of the southern Amazon Basin}, journal = {Water Resources Research}, year = {2008}, volume = {44}, number = {3}, url = {://WOS:000254169900001}, doi = {https://doi.org/10.1029/2006wr005526} } |
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Vourlitis, G.L., Nogueira, J.d.S., Lobo, F.d.A. and Pinto, O.B. | Variations in evapotranspiration andclimate for an Amazonian semi-deciduousforest over seasonal, annual, and El Niñocycles [BibTeX] |
2014 | Int J Biometeorol Vol. DOI: 10.1007/s00484-014-0837-1 |
article | DOI |
BibTeX:
@article{vourlitis_variations_2014, author = {Vourlitis, George L. and Nogueira, José de Souza and Lobo, Francisco de Almeida and Pinto, Osvaldo Borges}, title = {Variations in evapotranspiration andclimate for an Amazonian semi-deciduousforest over seasonal, annual, and El Niñocycles}, journal = {Int J Biometeorol}, year = {2014}, volume = {DOI: 10.1007/s00484-014-0837-1}, doi = {https://doi.org/10.1007/s00484-014-0837-1} } |
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Vourlitis, G.L., Lobo, F.d.A., Zeilhofer, P. and Nogueira, J.d.S. | Temporal patterns of net CO(2) exchange for a tropical semideciduous forest of the southern Amazon Basin | 2011 | Journal of Geophysical Research-Biogeosciences Vol. 116 |
article | DOI URL |
Abstract: The carbon cycling of tropical ecosystems has received considerable attention over the last 1-2 decades; however, interactions between climate variation and tropical forest net ecosystem CO(2) exchange (NEE) are still uncertain. To reduce this uncertainty, and assess the biophysical controls on NEE, we used the eddy covariance method over a 3 year period (2005-2008) to measure the CO(2) flux and energy balance for a 25-28 m tall, mature tropical semideciduous forest located near Sinop Mato Grosso, Brazil. The study period encompassed warm-dry, cool-wet, and cool-dry climate conditions, and based on previous research, we hypothesized that the net CO(2) accumulation of the semideciduous forest would be lower during periods of drought. Using time series of the enhanced vegetation index (EVI), a NEE-light-use model, and path analysis, we found that the estimated quantum yield (a', mu mol CO(2) mmol photons(-1)) was directly affected by temporal variations in the EVI, precipitation, and photosynthetically active radiation (PAR), while the optimal rate of gross primary production (F(GPP,opt), mu mol m(-2) s(-1)) was directly affected by the EVI and PAR. However, indirect effects of precipitation on the a' and F(GPP,opt) were stronger than direct effects because variations in precipitation also lead to variations in the EVI and the atmospheric vapor pressure deficit (VPD). Daytime ecosystem respiration (F(RE,day), mu mol m(-2) s(-1)) was directly affected by temporal variations in temperature and VPD and indirect effects of other variables were of lesser importance. Net ecosystem CO(2) uptake was often higher in the dry season than the wet season, not because of a dry season "green-up" but because rates of ecosystem respiration declined relatively more than rates of canopy photosynthesis. Over interannual timescales, average daily NEE increased over the 3 year study period and was highest in 2007-2008, which was also the driest year in terms of rainfall. However, 2007-2008 was also the coolest year during the 3 year study period, and the low temperature appeared to compensate for the low rainfall. Overall, our data suggest that the NEE of tropical semideciduous forests is sensitive to temporal variations in surface water availability but that indirect effects of other variables, such as temperature and VPD, are important in controlling CO(2) gain and loss. Such interactions will be important for the future NEE under warmer and drier conditions that are anticipated with anthropogenic climate change. | |||||
BibTeX:
@article{vourlitis_temporal_2011, author = {Vourlitis, George L. and Lobo, Francisco de Almeida and Zeilhofer, Peter and Nogueira, Jose de Souza}, title = {Temporal patterns of net CO(2) exchange for a tropical semideciduous forest of the southern Amazon Basin}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2011}, volume = {116}, url = {://WOS:000294803600001}, doi = {https://doi.org/10.1029/2010jg001524} } |
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Vourlitis, G.L., Lobo, F.d.A., Biudes, M.S., Rodriguez Ortiz, C.E. and Nogueira, J.d.S. | Spatial Variations in Soil Chemistry and Organic Matter Content across a Vochysia divergens Invasion Front in the Brazilian Pantanal | 2011 | Soil Science Society of America Journal Vol. 75(4), pp. 1554-1561 |
article | DOI URL |
Abstract: The Pantanal is a large and diverse wetland that spans three South American countries including parts of Brazil, Paraguay, and Bolivia. An invasive tree, Vochysia divergens Pohl (commonly known as Cambara), has been expanding throughout the Pantanal for more than four decades forming monospecific stands. Given the rapid and extensive spread of Cambara, and the potential for woody plant invasion to alter soil organic matter and nutrient stocks, we hypothesized that Cambara invasion would significantly increase soil organic matter and nutrient content. To test this hypothesis we sampled the soil, litter, and vegetation of a monospecific Cambara stand, a grassland (campo) stand in the process of Cambara invasion (transitional), and a campo stand free of Cambara during the dry season in July and August of 2009 and 2010 when stands were free from seasonal flooding. Surface (0-10 cm) soil in sites dominated by Cambara had significantly higher soil organic matter (SOM), P, and cation content, and higher cation exchange capacity (CEC), but soil pH and K(+) concentration were less coincident with Cambara presence. The variation of soil characteristics was also significantly higher in the transitional site, indicating that the transition from a grassland-to a Cambara-dominated system significantly increased the spatial variability of soil chemistry. These results indicate that Cambara invasion fundamentally alters the C and nutrient storage of Panatanal soils. Future research will investigate if these results are general for Cambara invasion and address mechanisms of how Cambara invasion affects the nutrient cycling and storage of Pantanal soils. | |||||
BibTeX:
@article{vourlitis_spatial_2011, author = {Vourlitis, George L. and Lobo, Francisco de Almeida and Biudes, Marcelo Sacardi and Rodriguez Ortiz, Carmen Eugenia and Nogueira, Jose de Souza}, title = {Spatial Variations in Soil Chemistry and Organic Matter Content across a Vochysia divergens Invasion Front in the Brazilian Pantanal}, journal = {Soil Science Society of America Journal}, year = {2011}, volume = {75}, number = {4}, pages = {1554--1561}, url = {://WOS:000293076400036}, doi = {https://doi.org/10.2136/sssaj2010.0412} } |
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Vourlitis, G., Hentz, C.S., Pinto Junior, O.B., Carneiro, E. and Nogueira, J.S. | Soil N, P, and C dynamics of upland and seasonally flooded forests of the Brazilian Pantanal [BibTeX] |
2017 | Global Ecology and Conservation Vol. 12, pp. 227-240 |
article | |
BibTeX:
@article{vourlitis_soil_2017, author = {Vourlitis, G.L. and Hentz, C. S. and Pinto Junior, O. B. and Carneiro, E. and Nogueira, J. S.}, title = {Soil N, P, and C dynamics of upland and seasonally flooded forests of the Brazilian Pantanal}, journal = {Global Ecology and Conservation}, year = {2017}, volume = {12}, pages = {227--240} } |
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Vourlitis, G. and Fernandez, J. | Changes in the soil, litter, and vegetation nitrogen and carbon concentrations of semiarid shrublands in response to chronic dry season nitrogen input [BibTeX] |
2012 | Journal of Arid Environments Vol. 82, pp. 115-122 |
article | |
BibTeX:
@article{vourlitis_changes_2012, author = {Vourlitis, G.L. and Fernandez, J.S.}, title = {Changes in the soil, litter, and vegetation nitrogen and carbon concentrations of semiarid shrublands in response to chronic dry season nitrogen input}, journal = {Journal of Arid Environments}, year = {2012}, volume = {82}, pages = {115--122} } |
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von Randow, R.d.C.S., Tomasella, J., von Randow, C., de Araújo, A.C., Manzi, A.O., Hutjes, R. and Kruijt, B. | Evapotranspiration and gross primary productivity of secondary vegetation in Amazonia inferred by eddy covariance | 2020 | Agricultural and Forest Meteorology Vol. 294, pp. 108141 |
article | DOI URL |
Abstract: The conversion of primary forest (PF) to other types of land cover, such as pasture and agriculture, in Amazonia, affects regional carbon and water balances, significantly contributing to increased carbon emissions and reduced evapotranspiration. However, secondary forest (SF) growth, resulting from the abandonment of low-productivity pasture areas, offers a potential alternative to counterbalance the effects of deforestation on carbon release to the atmosphere and evapotranspiration reduction. In this work, we present four years of eddy flux measurements of a SF that is approximately 20 years old, located in Central Amazonia, and we compare these measurements with those of a PF in the same region, analyzing daily and seasonal variations in evapotranspiration, gross primary productivity of carbon and water use efficiency. On average, evapotranspiration is 20% higher in the SF (3.6 mm day−1) than in the PF (3.1 mm day−1), while gross primary productivity is only 5% higher in the SF (8.1 gC m−2 day−1) than in the PF (7.8 gC m−2 day−1). Despite robust evidence of higher evapotranspiration and gross primary productivity in SF, the estimated uncertainty range of WUE is large to reach definite conclusions about the differences on carbon gain per water loss between the sites. Nonetheless, the significantly higher evapotranspiration and gross primary productivity of SF may counterbalance both water and C losses from deforestation and has important implications for regional budgets. | |||||
BibTeX:
@article{von_randow_evapotranspiration_2020, author = {von Randow, Rita de Cassia Silva and Tomasella, Javier and von Randow, Celso and de Araújo, Alessandro Carioca and Manzi, Antonio Ocimar and Hutjes, Ronald and Kruijt, Bart}, title = {Evapotranspiration and gross primary productivity of secondary vegetation in Amazonia inferred by eddy covariance}, journal = {Agricultural and Forest Meteorology}, year = {2020}, volume = {294}, pages = {108141}, url = {https://www.sciencedirect.com/science/article/pii/S0168192320302434}, doi = {https://doi.org/10.1016/j.agrformet.2020.108141} } |
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von Randow, R., von Randow, C., Hutjes, R., Tomasella, J. and Kruijt, B. | Evapotranspiration of deforested areas in central and southwestern Amazonia [BibTeX] |
2011 | Theoretical and Applied Climatology, pp. DOI 10.1007/s00704-011-0570-1 (2012) | article | |
BibTeX:
@article{von_randow_evapotranspiration_2011, author = {von Randow, R.C.S. and von Randow, C. and Hutjes, R.W.A. and Tomasella, J. and Kruijt, B.}, title = {Evapotranspiration of deforested areas in central and southwestern Amazonia}, journal = {Theoretical and Applied Climatology}, year = {2011}, pages = {DOI 10.1007/s00704--011--0570--1 (2012)} } |
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von Randow, Marcelo Restrepo-Coupe, Natalia Muza, Michel N. de Gonçalves, Luis Gustavo G. Costa, Marcos H. Araujo, Alessandro C. Manzi, Antonio o. Da Rocha, Humberto r. Saleska, Scott R. Arain, M. Alaf Baker, Ian T. Cestaro, Bruno P. Christoffersen, Bradley Ciais, Philippe Fisher, Joshua b. Galbraith, david guan, xiaodan van den hurk, bart ichii, kazuhito imbuzeiro, hewlley jain, atul levine, naomi miguez-Macho, Gonzalo Poulter, Ben, et al., Celso Zeri | Inter-annual variability of carbon and water fluxes in Amazonian forest, Cerrado and pasture sites, as simulated by terrestrial biosphere models [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183, pp. 145-155 |
article | |
BibTeX:
@article{von_randow_inter-annual_2013, author = {von Randow, Marcelo Restrepo-Coupe, Natalia Muza, Michel N. de Gonçalves, Luis Gustavo G. Costa, Marcos H. Araujo, Alessandro C. Manzi, Antonio o. Da Rocha, Humberto r. Saleska, Scott R. Arain, M. Alaf Baker, Ian T. Cestaro, Bruno P. Christoffersen, Bradley Ciais, Philippe Fisher, Joshua b. Galbraith, david guan, xiaodan van den hurk, bart ichii, kazuhito imbuzeiro, hewlley jain, atul levine, naomi miguez-Macho, Gonzalo Poulter, Ben, et al., Celso Zeri}, title = {Inter-annual variability of carbon and water fluxes in Amazonian forest, Cerrado and pasture sites, as simulated by terrestrial biosphere models}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, pages = {145--155} } |
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von Randow, C., Sa, L.D.A., Gannabathula, P., Manzi, A.O., Arlino, P.R.A. and Kruijt, B. | Scale variability of atmospheric surface layer fluxes of energy and carbon over a tropical rain forest in southwest Amazonia - 1. Diurnal conditions | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: The aim of this study is to investigate the low-frequency characteristics of diurnal turbulent scalar spectra and cospectra near the Amazonian rain forest during the wet and dry seasons. This is because the available turbulent data are often nonstationary and there is no clear spectral gap to separate data into "mean" and "turbulent" parts. Daubechies-8 orthogonal wavelet is used to scale project turbulent signals in order to provide scale variance and covariance estimations. Based on the characteristics of the scale dependence of the scalar fluxes, some classification criteria of this scale dependence are investigated. The total scalar covariance of each 4-hour data run is partitioned in categories of scale covariance contributions. This permits the study of some statistical characteristics of the scalar turbulent fields in each one of these classes and, thus, to give an insight and a possible explanation of the origin of the variability of the scalar fields close to the Amazonian forest. The results have shown that a two-category classification is the most appropriate to describe the kind of observed fluctuations: "turbulent" and "mesoscale" contributions. The largest contribution of the sensible heat, latent heat, and CO2 covariance contributions occurs in the "turbulent" length scales. Mesoscale eddy motions, however, can contribute up to 30% of the total covariances under weak wind conditions. Analysis of scale correlation coefficient [r(T(v)q)] between virtual temperature (T-v) and humidity (q) signals shows that the scale patterns of T-v and q variability are not similar and r(T(v)q) textless 1 for all analyzed scales. Scale humidity skewness calculations are negative during the dry season and positive during the wet season. This suggests that different boundary layer moisture regimes occur during the dry and wet seasons. | |||||
BibTeX:
@article{von_randow_scale_2002, author = {von Randow, C. and Sa, L. D. A. and Gannabathula, Pssd and Manzi, A. O. and Arlino, P. R. A. and Kruijt, B.}, title = {Scale variability of atmospheric surface layer fluxes of energy and carbon over a tropical rain forest in southwest Amazonia - 1. Diurnal conditions}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200018}, doi = {https://doi.org/10.1029/2001jd000379} } |
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von Randow, C., Manzi, A.O., Kruijt, B., de Oliveira, P.J., Zanchi, F.B., Silva, R.L., Hodnett, M.G., Gash, J.H.C., Elbers, J.A., Waterloo, M.J., Cardoso, F.L. and Kabat, P. | Comparative measurements and seasonal variations in energy and carbon exchange over forest and pasture in South West Amazonia | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 5-26 |
article | DOI URL |
Abstract: Comparative measurements of radiation flux components and turbulent fluxes of energy and CO2 are made at two sites in South West Amazonia: one in a tropical forest reserve and one in a pasture. The data were collected from February 1999 to September 2002, as part of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). During the dry seasons, although precipitation and specific humidity are greatly reduced, the soil moisture storage profiles down to 3.4 m indicate that the forest vegetation continues to withdraw water from deep layers in the soil. For this reason, seasonal changes observed in the energy partition and CO2 fluxes in the forest are small, compared to the large reductions in evaporation and photosynthesis observed in the pasture. For the radiation balance, the reflected short wave radiation increases by about 55% when changing from forest to pasture. Combined with an increase of 4.7% in long wave radiation loss, this causes an average reduction of 13.3% in net radiation in the pasture, compared to the forest. In the wet season, the evaporative fraction (lambdaE/R-n) at the pasture is 17% lower than at the forest. This difference increases to 24% during the dry season. Daytime CO2 fluxes are 20-28% lower (in absolute values) in the pasture compared to the forest. The night-time respiration in the pasture is also reduced compared to the forest, with averages 44% and 57% lower in the wet and dry seasons, respectively. As the reduction in the nocturnal respiration is larger than the reduction in the daytime uptake, the combined effect is a 19-67% higher daily uptake of CO2 in the pasture, compared to the forest. This high uptake of CO2 in the pasture site is not surprising, since the growth of the vegetation is constantly renewed, as the cattle remove the biomass. | |||||
BibTeX:
@article{von_randow_comparative_2004, author = {von Randow, C. and Manzi, A. O. and Kruijt, B. and de Oliveira, P. J. and Zanchi, F. B. and Silva, R. L. and Hodnett, M. G. and Gash, J. H. C. and Elbers, J. A. and Waterloo, M. J. and Cardoso, F. L. and Kabat, P.}, title = {Comparative measurements and seasonal variations in energy and carbon exchange over forest and pasture in South West Amazonia}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {5--26}, url = {://WOS:000222024700003}, doi = {https://doi.org/10.1007/s00704-004-0041-z} } |
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von Randow, C., Kruijt, B., Holtslag, A.A.M. and de Oliveira, M.B.L. | Exploring eddy-covariance and large-aperture scintillometer measurements in an Amazonian rain forest | 2008 | Agricultural and Forest Meteorology Vol. 148(4), pp. 680-690 |
article | DOI URL |
Abstract: A large-aperture scintillometer (LAS) is used to estimate the surface sensible heat fluxes in an Amazonian rain forest site, and these fluxes are compared with an eddy-covariance system (EC) to analyze conditions of low-frequency modulation in the surface layer. The results show that the flux estimates from the EC are often lower than from the LAS. The differences between EC and LAS tend to increase with decreasing correlation between vertical wind and temperature (r(omega T))- Using different averaging times on EC calculations, we observe that the largest differences between the LAS and the EC fluxes are found for 10-min averages, less so for 30-min averages, while 1-h averages give the smallest differences. The results are attributed to the spatial averaging effect of the LAS. Generally, the results suggest that r(omega T) can be used as an indicator of the importance of low-frequency motions in the surface layer. Evaluating the energy balance for different ranges Of r(omega T) we found that its closure improves when data with increasingly higher r(omega T) are used. In addition, a methodology has been developed to correct the scintillometer signals for the effect of tower vibrations. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{von_randow_exploring_2008, author = {von Randow, Celso and Kruijt, Bart and Holtslag, Albert A. M. and de Oliveira, Maria Betania L.}, title = {Exploring eddy-covariance and large-aperture scintillometer measurements in an Amazonian rain forest}, journal = {Agricultural and Forest Meteorology}, year = {2008}, volume = {148}, number = {4}, pages = {680--690}, url = {://WOS:000255455700013}, doi = {https://doi.org/10.1016/j.agrformet.2007.11.011} } |
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von Randow, C., Kruijt, B. and Holtslag, A.A.M. | Low-frequency modulation of the atmospheric surface layer over Amazonian rain forest and its implication for similarity relationships | 2006 | Agricultural and Forest Meteorology Vol. 141(2-4), pp. 192-207 |
article | DOI URL |
Abstract: The application of Monin-Obukhov similarity theory (MOS) is based on empirical relationships derived over uniform surfaces in flat terrain. It is not clear to what extent these relationships hold for complex surfaces such as tropical forest or hilly terrain. This study investigates the influence of low-frequency motions in the structure of the atmospheric surface layer over Amazonian forest and its implication for the application of MOS theory. We test the estimation of heat fluxes by the flux-variance method, which is based on MOS theory, for measurements in unstable conditions in the K34 forest site in central Amazonia, north of Manaus, Brazil. It is found that the MOS relationships and the flux-variance method provide reasonable results only when the w - T correlation (r(wT)) is above 0.5. Examining the scale dependence of r(wT) and of u - w correlation (r(uw)) revealed that w variations tend to be not well correlated with fluctuations in u or Tat low frequencies. In this sense, a greater influence of low-frequency processes tends to cause r(wT) and r(uw) to decrease, and in these conditions the surface layer cannot be characterized by the 'textbook' descriptions of the surface layer observed over uniform terrain. As an alternative to the conventional MOS scaling, we test the use of the 'dissipation velocity' u(epsilon), = (kze)(1/3), proposed by McNaughton [McNaughton, K.G., 2006. On the kinetic energy budget of the unstable atmospheric surface layer. Boundary-Layer Meteorol. 118, 83-107], to scale the standard deviations and parameterize the modulation of low-frequency motions. The systematic variation with stability is taken out by the use of the new parameters, and the scaled variables become independent of the MOS stability parameter. This result is consistent with the self-organizing nature of the turbulent structure in the modulated surface layer. The results highlight the complexities of the surface layer above vegetation such as Amazonian forest. Estimations of the parameter v(*)/u(*), which represent the modulation of the outer-layer motions on the surface layer, indicate that during roughly 20% of the time the unstable surface layer above the forest deviates from the 'classical' description. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{von_randow_low-frequency_2006, author = {von Randow, Celso and Kruijt, Bart and Holtslag, Albert A. M.}, title = {Low-frequency modulation of the atmospheric surface layer over Amazonian rain forest and its implication for similarity relationships}, journal = {Agricultural and Forest Meteorology}, year = {2006}, volume = {141}, number = {2-4}, pages = {192--207}, url = {://WOS:000243669500009}, doi = {https://doi.org/10.1016/j.agrformet.2006.10.005} } |
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Viljur, M.-L., Abella, S.R., Adámek, M., Alencar, J.B.R., Barber, N.A., Beudert, B., Burkle, L.A., Cagnolo, L., Campos, B.R., Chao, A., Chergui, B., Choi, C.-Y., Cleary, D.F.R., Davis, T.S., Dechnik-Vázquez, Y.A., Downing, W.M., Fuentes-Ramirez, A., Gandhi, K.J.K., Gehring, C., Georgiev, K.B., Gimbutas, M., Gongalsky, K.B., Gorbunova, A.Y., Greenberg, C.H., Hylander, K., Jules, E.S., Korobushkin, D.I., Köster, K., Kurth, V., Lanham, J.D., Lazarina, M., Leverkus, A.B., Lindenmayer, D., Marra, D.M., Martín-Pinto, P., Meave, J.A., Moretti, M., Nam, H.-Y., Obrist, M.K., Petanidou, T., Pons, P., Potts, S.G., Rapoport, I.B., Rhoades, P.R., Richter, C., Saifutdinov, R.A., Sanders, N.J., Santos, X., Steel, Z., Tavella, J., Wendenburg, C., Wermelinger, B., Zaitsev, A.S. and Thorn, S. | The effect of natural disturbances on forest biodiversity: an ecological synthesis | 2022 | Biological Reviews Vol. 97(5), pp. 1930-1947 |
article | DOI URL |
Abstract: ABSTRACT Disturbances alter biodiversity via their specific characteristics, including severity and extent in the landscape, which act at different temporal and spatial scales. Biodiversity response to disturbance also depends on the community characteristics and habitat requirements of species. Untangling the mechanistic interplay of these factors has guided disturbance ecology for decades, generating mixed scientific evidence of biodiversity responses to disturbance. Understanding the impact of natural disturbances on biodiversity is increasingly important due to human-induced changes in natural disturbance regimes. In many areas, major natural forest disturbances, such as wildfires, windstorms, and insect outbreaks, are becoming more frequent, intense, severe, and widespread due to climate change and land-use change. Conversely, the suppression of natural disturbances threatens disturbance-dependent biota. Using a meta-analytic approach, we analysed a global data set (with most sampling concentrated in temperate and boreal secondary forests) of species assemblages of 26 taxonomic groups, including plants, animals, and fungi collected from forests affected by wildfires, windstorms, and insect outbreaks. The overall effect of natural disturbances on α-diversity did not differ significantly from zero, but some taxonomic groups responded positively to disturbance, while others tended to respond negatively. Disturbance was beneficial for taxonomic groups preferring conditions associated with open canopies (e.g. hymenopterans and hoverflies), whereas ground-dwelling groups and/or groups typically associated with shady conditions (e.g. epigeic lichens and mycorrhizal fungi) were more likely to be negatively impacted by disturbance. Across all taxonomic groups, the highest α-diversity in disturbed forest patches occurred under moderate disturbance severity, i.e. with approximately 55% of trees killed by disturbance. We further extended our meta-analysis by applying a unified diversity concept based on Hill numbers to estimate α-diversity changes in different taxonomic groups across a gradient of disturbance severity measured at the stand scale and incorporating other disturbance features. We found that disturbance severity negatively affected diversity for Hill number q =?0 but not for q =?1 and q =?2, indicating that diversity?disturbance relationships are shaped by species relative abundances. Our synthesis of α-diversity was extended by a synthesis of disturbance-induced change in species assemblages, and revealed that disturbance changes the ?-diversity of multiple taxonomic groups, including some groups that were not affected at the α-diversity level (birds and woody plants). Finally, we used mixed rarefaction/extrapolation to estimate biodiversity change as a function of the proportion of forests that were disturbed, i.e. the disturbance extent measured at the landscape scale. The comparison of intact and naturally disturbed forests revealed that both types of forests provide habitat for unique species assemblages, whereas species diversity in the mixture of disturbed and undisturbed forests peaked at intermediate values of disturbance extent in the simulated landscape. Hence, the relationship between α-diversity and disturbance severity in disturbed forest stands was strikingly similar to the relationship between species richness and disturbance extent in a landscape consisting of both disturbed and undisturbed forest habitats. This result suggests that both moderate disturbance severity and moderate disturbance extent support the highest levels of biodiversity in contemporary forest landscapes. | |||||
BibTeX:
@article{viljur_effect_2022, author = {Viljur, Mari-Liis and Abella, Scott R. and Adámek, Martin and Alencar, Janderson Batista Rodrigues and Barber, Nicholas A. and Beudert, Burkhard and Burkle, Laura A. and Cagnolo, Luciano and Campos, Brent R. and Chao, Anne and Chergui, Brahim and Choi, Chang-Yong and Cleary, Daniel F. R. and Davis, Thomas Seth and Dechnik-Vázquez, Yanus A. and Downing, William M. and Fuentes-Ramirez, Andrés and Gandhi, Kamal J. K. and Gehring, Catherine and Georgiev, Kostadin B. and Gimbutas, Mark and Gongalsky, Konstantin B. and Gorbunova, Anastasiya Y. and Greenberg, Cathryn H. and Hylander, Kristoffer and Jules, Erik S. and Korobushkin, Daniil I. and Köster, Kajar and Kurth, Valerie and Lanham, Joseph Drew and Lazarina, Maria and Leverkus, Alexandro B. and Lindenmayer, David and Marra, Daniel Magnabosco and Martín-Pinto, Pablo and Meave, Jorge A. and Moretti, Marco and Nam, Hyun-Young and Obrist, Martin K. and Petanidou, Theodora and Pons, Pere and Potts, Simon G. and Rapoport, Irina B. and Rhoades, Paul R. and Richter, Clark and Saifutdinov, Ruslan A. and Sanders, Nathan J. and Santos, Xavier and Steel, Zachary and Tavella, Julia and Wendenburg, Clara and Wermelinger, Beat and Zaitsev, Andrey S. and Thorn, Simon}, title = {The effect of natural disturbances on forest biodiversity: an ecological synthesis}, journal = {Biological Reviews}, year = {2022}, volume = {97}, number = {5}, pages = {1930--1947}, url = {https://doi.org/10.1111/brv.12876}, doi = {https://doi.org/10.1111/brv.12876} } |
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Vilani, S., Nogueira, L., Priante Filho, J.S. and M.T., N.P. | Sazonalidade da radiação, temperatura e umidade em uma floresta de transição amazônia cerrado [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 331-343 |
article | |
BibTeX:
@article{vilani_sazonalidade_2006, author = {Vilani, Sanches, L., Nogueira, J.S., Priante Filho, N.P., M.T.}, title = {Sazonalidade da radiação, temperatura e umidade em uma floresta de transição amazônia cerrado}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {331--343} } |
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Vila, D.A., Machado, L.A.T., Laurent, H. and Velasco, I. | Forecast and Tracking the Evolution of Cloud Clusters (ForTraCC) using satellite infrared imagery: Methodology and validation | 2008 | Weather and Forecasting Vol. 23(2), pp. 233-245 |
article | DOI URL |
Abstract: The purpose of this study is to develop and validate an algorithm for tracking and forecasting radiative and morphological characteristics of mesoscale convective systems (MCSs) through their entire life cycles using geostationary satellite thermal channel information (10.8 mu m). The main features of this system are the following: 1) a cloud cluster detection method based on a threshold temperature (235 K), 2) a tracking technique based on MCS overlapping areas in successive images, and 3) a forecast module based on the evolution of each particular MCS in previous steps. This feature is based on the MCS's possible displacement (considering the center of the mass position of the cloud cluster in previous time steps) and its size evolution. Statistical information about MCS evolution during the Wet Season Atmospheric Mesoscale Campaign (WETAMC) of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) was used to obtain area expansion mean rates for different MCSs according to their lifetime durations. This nowcasting tool was applied to evaluate the MCS displacement and size evolution over the Del Plata basin in South America up to 120 min with 30-min intervals. The Forecast and Tracking the Evolution of Cloud Clusters (ForTraCC) technique's performance was evaluated based on the difference between the forecasted and observed images. This evaluation shows good agreement between the observed and forecast size and minimum temperature for shorter forecast lead times, but tends to underestimate MCS size (and overestimate the minimum temperature) for larger forecast lead times. | |||||
BibTeX:
@article{vila_forecast_2008, author = {Vila, Daniel Alejandro and Machado, Luiz Augusto Toledo and Laurent, Henri and Velasco, Ines}, title = {Forecast and Tracking the Evolution of Cloud Clusters (ForTraCC) using satellite infrared imagery: Methodology and validation}, journal = {Weather and Forecasting}, year = {2008}, volume = {23}, number = {2}, pages = {233--245}, url = {://WOS:000255077500003}, doi = {https://doi.org/10.1175/2007waf2006121.1} } |
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Vihermaa, L., Waldron, S., Garnett, M. and Newton, J. | Old carbon contributes to aquatic emissions of carbon dioxide in the Amazon [BibTeX] |
2014 | Biogeosciences Vol. 11, pp. 3635-3645 |
article | DOI |
BibTeX:
@article{vihermaa_old_2014, author = {Vihermaa, L.E. and Waldron, S. and Garnett, M.H. and Newton, J.}, title = {Old carbon contributes to aquatic emissions of carbon dioxide in the Amazon}, journal = {Biogeosciences}, year = {2014}, volume = {11}, pages = {3635--3645}, doi = {https://doi.org/10.5194/bg-11-3635-2014} } |
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Vieira, P., Andreoli R.V., S. and Satyamurty | On the South Atlantic Convergence Zone affecting southern Amazonia in austral summer [BibTeX] |
2013 | Atmospheric Science Letters Vol. 14, pp. 01-06 |
article | |
BibTeX:
@article{vieira_south_2013, author = {Vieira, P.; Andreoli, R.V., S.O.; Satyamurty}, title = {On the South Atlantic Convergence Zone affecting southern Amazonia in austral summer}, journal = {Atmospheric Science Letters}, year = {2013}, volume = {14}, pages = {01--06} } |
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Vieira, S., Trumbore, S., Camargo, P.B., Selhorst, D., Chambers, J.Q., Higuchi, N. and Martinelli, L.A. | Slow growth rates of Amazonian trees: Consequences for carbon cycling | 2005 | Proceedings of the National Academy of Sciences of the United States of America Vol. 102(51), pp. 18502-18507 |
article | DOI URL |
Abstract: Quantifying age structure and tree growth rate of Amazonian forests is essential for understanding their role in the carbon cycle. Here, we use radiocarbon dating and direct measurement of diameter increment to document unexpectedly slow growth rates for trees from three locations spanning the Brazilian Amazon basin. Central Amazon trees, averaging only approximate to 1 mm/year diameter increment, grow half as fast as those from areas with more seasonal rainfall to the east and west. Slow growth rates mean that trees can attain great ages; across our sites we estimate 17-50% of trees with diameter textgreater 10 cm have ages exceeding 300 years. Whereas a few emergent trees that make up a large portion of the biomass grow faster, small trees that are more abundant grow slowly and attain ages of hundreds of years. The mean age of carbon in living trees (60-110 years) is within the range of or slightly longer than the mean residence time calculated from C inventory divided by annual C allocation to wood growth (40-100 years). Faster C turnover is observed in stands with overall higher rates of diameter increment and a larger fraction of the biomass in large, fast-growing trees. As a consequence, forests can recover biomass relatively quickly after disturbance, whereas recovering species composition may take many centuries. Carbon cycle models that apply a single turnover time for carbon in forest biomass do not account for variations in life strategy and therefore may overestimate the carbon sequestration potential of Amazon forests. | |||||
BibTeX:
@article{vieira_slow_2005, author = {Vieira, S. and Trumbore, S. and Camargo, P. B. and Selhorst, D. and Chambers, J. Q. and Higuchi, N. and Martinelli, L. A.}, title = {Slow growth rates of Amazonian trees: Consequences for carbon cycling}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2005}, volume = {102}, number = {51}, pages = {18502--18507}, note = {Edition: 2005/12/13}, url = {://WOS:000234174300047}, doi = {https://doi.org/10.1073/pnas.0505966102} } |
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Vieira, S., de Camargo, P.B., Selhorst, D., da Silva, R., Hutyra, L., Chambers, J.Q., Brown, I.F., Higuchi, N., dos Santos, J., Wofsy, S.C., Trumbore, S.E. and Martinelli, L.A. | Forest structure and carbon dynamics in Amazonian tropical rain forests | 2004 | Oecologia Vol. 140(3), pp. 468-479 |
article | DOI URL |
Abstract: Living trees constitute one of the major stocks of carbon in tropical forests. A better understanding of variations in the dynamics and structure of tropical forests is necessary for predicting the potential for these ecosystems to lose or store carbon, and for understanding how they recover from disturbance. Amazonian tropical forests occur over a vast area that encompasses differences in topography, climate, and geologic substrate. We observed large differences in forest structure, biomass, and tree growth rates in permanent plots situated in the eastern (near Santarem, Para), central (near Manaus, Amazonas) and southwestern (near Rio Branco, Acre) Amazon, which differed in dry season length, as well as other factors. Forests at the two sites experiencing longer dry seasons, near Rio Branco and Santarem, had lower stem frequencies (460 and 466 ha(-1) respectively), less biodiversity (Shannon-Wiener diversity index), and smaller aboveground C stocks (140.6 and 122.1 Mg C ha(-1)) than the Manaus site (626 trees ha(-1), 180.1 Mg C ha(-1)), which had less seasonal variation in rainfall. The forests experiencing longer dry seasons also stored a greater proportion of the total biomass in trees with textgreater50 cm diameter (41-45 vs 30% in Manaus). Rates of annual addition of C to living trees calculated from monthly dendrometer band measurements were 1.9 (Manaus), 2.8 (Santarem), and 2.6 (Rio Branco) Mg C ha(-1) year(-1). At all sites, trees in the 10-30 cm diameter class accounted for the highest proportion of annual growth (38, 55 and 56% in Manaus, Rio Branco and Santarem, respectively). Growth showed marked seasonality, with largest stem diameter increment in the wet season and smallest in the dry season, though this may be confounded by seasonal variation in wood water content. Year-to-year variations in C allocated to stem growth ranged from nearly zero in Rio Branco, to 0.8 Mg C ha(-1) year(-1) in Manaus (40% of annual mean) and 0.9 Mg C ha(-1) year(-1) (33% of annual mean) in Santarem, though this variability showed no significant relation with precipitation among years. Initial estimates of the C balance of live wood including recruitment and mortality as well as growth suggests that live wood biomass is at near steady-state in Manaus, but accumulating at about 1.5 Mg C ha(-1) at the other two sites. The causes of C imbalance in living wood pools in Santarem and Rio Branco sites are unknown, but may be related to previous disturbance at these sites. Based on size distribution and growth rate differences in the three sites, we predict that trees in the Manaus forest have greater mean age (similar to240 years) than those of the other two forests (similar to140 years). | |||||
BibTeX:
@article{vieira_forest_2004, author = {Vieira, S. and de Camargo, P. B. and Selhorst, D. and da Silva, R. and Hutyra, L. and Chambers, J. Q. and Brown, I. F. and Higuchi, N. and dos Santos, J. and Wofsy, S. C. and Trumbore, S. E. and Martinelli, L. A.}, title = {Forest structure and carbon dynamics in Amazonian tropical rain forests}, journal = {Oecologia}, year = {2004}, volume = {140}, number = {3}, pages = {468--479}, note = {Edition: 2004/06/29}, url = {://WOS:000223008700011}, doi = {https://doi.org/10.1007/s00442-004-1598-z} } |
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Vieira, I.C.G., Toledo, P.M.d. and Araújo Jr., R.S.O. | The Socioecological Implications of Land Use and Landscape Change in the Brazilian Amazon [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 441-462 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_socioecological_2016, author = {Vieira, Ima C. G. and Toledo, Peter M. de and Araújo Jr., Roberto S. O.}, title = {The Socioecological Implications of Land Use and Landscape Change in the Brazilian Amazon}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {441--462}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Vieira, I.C.G., de Almeida, A.S., Davidson, E.A., Stone, T.A., de Carvalho, C.J.R. and Guerrero, J.B. | Classifying successional forests using Landsat spectral properties and ecological characteristics in eastern Amazonia | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 470-481 |
article | DOI URL |
Abstract: Secondary forests may become increasingly important as temporary reservoirs of genetic diversity, stocks of carbon and nutrients, and moderators of hydrologic cycles in the Amazon Basin as agricultural lands are abandoned and often later cleared again for agriculture. We studied a municipality in northeastern Par, Brazil, that has been settled for over a century and where numerous cycles of slash and burn agriculture have occurred. The forests were grouped into young (3-6 years), intermediate (10-20 years), advanced (40-70 years), and mature successional stages using 1999 Landsat 7 ETM imagery. Supervised classification of the imagery showed that these forest classes occupied 22%, 13%, 9%, and 6% of the area, respectively. Although this area underwent widespread deforestation many decades ago, forest of some type covers about 50% of the area. Row crops, tree crops, and pastures cover 8%, 20%, and 22%, respectively. The best separation among land covers appeared in a plot of NDVI versus band 5 reflectance. The same groupings of successional forests were derived independently from indices of similarity among tree species composition. Measured distributions of tree height and diameter also covaried with these successional classes, with the young forests having nearly uniform distributions, whereas multiple height and diameter classes were present in the advanced successional forests. Biomass accumulated more slowly in this secondary forest chronosequence than has been reported for other areas, which explains why the 70-year-old forests here were still distinguishable from mature forests using spectral properties. Rates of forest regrowth may vary across regions due to differences in edaphic, climatic, and historical land-use factors, thus rendering most relationships among spectral properties and forest age site-specific. Successional status, as characterized by species composition, biomass, and distributions of heights and diameters, may be superior to stand age as a means of stratifying these forests for characterization of spectral properties. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{vieira_classifying_2003, author = {Vieira, I. C. G. and de Almeida, A. S. and Davidson, E. A. and Stone, T. A. and de Carvalho, C. J. R. and Guerrero, J. B.}, title = {Classifying successional forests using Landsat spectral properties and ecological characteristics in eastern Amazonia}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {470--481}, url = {://WOS:000186827400007}, doi = {https://doi.org/10.1016/j.rse.2002.09.002} } |
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Victoria, D.d.C., Santiago, A.V., Ramos Ballester, M.V., Pereira, A.R., Victoria, R.L. and Richey, J.E. | Water balance for the Ji-Parana River Basin, Western Amazon, using a simple method through geographical information systems and remote sensing | 2007 | Earth Interactions Vol. 11 |
article | DOI URL |
Abstract: The Thornthwaite-Mather climatological model integrated into a Geographic Information System (GIS) was used to simulate the monthly water balance for the Ji-Parana river basin, in the western Amazonian state of Rondonia (RO), from February 1995 through December 1996. Model inputs were Advanced Very High Resolution Radar (AVHRR) images, rainfall from rain gauges within and around the basin, soils, and land cover maps. Mean monthly temperature images, estimated from AVHRR, were used to calculate monthly potential evapotranspiration images. Rainfall measurements were interpolated to obtain monthly rainfall images using the spline method. Results were compared with annual water mass balance for 10 internal subbasins. Model results underestimated basin evapotranspiration in -6% and water surplus was overestimated in +12%. Annual basin evapotranspiration was 1166 mm, or 3.2 mm day(-1), with a minimum in the dry season (1.7 mm day(-1) in July) and maximum in the beginning of the wet season (4.2 mm day(-1) in October). Three distinct land cover scenarios were evaluated. Complete basin deforestation reduced basin evapotranspiration and increased water deficit and surplus in approximately 200 mm yr(-1). | |||||
BibTeX:
@article{victoria_water_2007, author = {Victoria, Daniel de Castro and Santiago, Alailson Venceslau and Ramos Ballester, Maria Victoria and Pereira, Antonio Roberto and Victoria, Reynaldo Luiz and Richey, Jeffrey E.}, title = {Water balance for the Ji-Parana River Basin, Western Amazon, using a simple method through geographical information systems and remote sensing}, journal = {Earth Interactions}, year = {2007}, volume = {11}, url = {://WOS:000245809500001}, doi = {https://doi.org/10.1175/ei198.1} } |
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Viana, R., Ferraz, J.B., Neves, A., Vieira, G. and Pereira, B. | Soil quality indicators for different restoration stages on Amazon rainforest [BibTeX] |
2014 | Soil & Tillage Research Vol. 1-7, pp. 140 |
article | |
BibTeX:
@article{viana_soil_2014, author = {Viana, R.M. and Ferraz, J. B.S. and Neves, A.F. and Vieira, G. and Pereira, B.F.F.}, title = {Soil quality indicators for different restoration stages on Amazon rainforest}, journal = {Soil & Tillage Research}, year = {2014}, volume = {1-7}, pages = {140} } |
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Viana, L., Bustamante, M., Molina, M., Pinto, A., Kisselle, K., Zepp, R. and Burke, R. | Microbial communities in Cerrado soils under native vegetation subjected to prescribed fire and under pasture [BibTeX] |
2011 | Pesquisa Agropecuaria Brasileira Vol. 46(12), pp. 1665-1672 |
article | |
BibTeX:
@article{viana_microbial_2011, author = {Viana, L.T. and Bustamante, M.M.C. and Molina, M. and Pinto, A.S.P. and Kisselle, K. and Zepp, R. and Burke, R.A.}, title = {Microbial communities in Cerrado soils under native vegetation subjected to prescribed fire and under pasture}, journal = {Pesquisa Agropecuaria Brasileira}, year = {2011}, volume = {46}, number = {12}, pages = {1665--1672} } |
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Vestin, A., Rissler, J., Swietlicki, E., Frank, G.P. and Andreae, M.O. | Cloud-nucleating properties of the Amazonian biomass burning aerosol: Cloud condensation nuclei measurements and modeling | 2007 | Journal of Geophysical Research-Atmospheres Vol. 112(D14) |
article | DOI URL |
Abstract: The cloud-nucleating properties of the atmospheric aerosol were studied in an area under strong influence of vegetation burning. The measurements were part of Large-Scale Biosphere Atmosphere Experiment in Amazonia-Smoke Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) and were carried out at a ground site located in the state of Rondonia in southwestern Amazonia, Brazil, September to November 2002, covering the dry season, a transition period, and the onset of the wet season. The concentrations of cloud condensation nuclei (CCN) were measured with a static thermal gradient CCN counter for supersaturations ranging between 0.23 and 1.12%. As a closure test, the CCN concentrations were predicted with a time resolution of 10 min from measurements of the dry particle number size distribution (3-850 nm, Differential Mobility Analyzer (DMPS)) and hygroscopic growth at 90% relative humidity (Hygroscopic Tandem Differential Mobility Analyzer (H-TDMA)). No chemical information was needed. The predicted and measured CCN concentrations were highly correlated (r(2)=0.97-0.99), and the predictions were only slightly lower than those measured, typically by 15-20%. Parameterizations of the predicted CCN concentrations are given for each of the three meteorological periods. These are based on averages taken during the afternoon hours when the measurements at ground level were representative for the aerosol entering the base of convective clouds. Furthermore, a more detailed parameterization including the mixing state of the aerosol is given, where the hygroscopic properties are expressed as the number of soluble ions or nondissociating molecules per unit volume dry particle. | |||||
BibTeX:
@article{vestin_cloud-nucleating_2007, author = {Vestin, A. and Rissler, J. and Swietlicki, E. and Frank, G. P. and Andreae, M. O.}, title = {Cloud-nucleating properties of the Amazonian biomass burning aerosol: Cloud condensation nuclei measurements and modeling}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2007}, volume = {112}, number = {D14}, url = {://WOS:000248285700006 http://www.agu.org/journals/jd/jd0714/2006JD008104/2006JD008104.pdf}, doi = {https://doi.org/10.1029/2006jd008104} } |
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Verissimo, A., Cochrane, M.A., Souza, C. and Salomao, R. | Priority areas for establishing national forests in the Brazilian Amazon | 2002 | Conservation Ecology Vol. 6(1) |
article | URL |
Abstract: Brazil will benefit if it gains control of its vast Amazonian timber resources. Without immediate planning, the fate of much of the Amazon will be decided by predatory and largely unregulated timber interests. Logging in the Amazon is a transient process of natural resource mining. Older logging frontiers are being exhausted of timber resources and will face severe wood shortages within 5 yr. The Brazilian government can avoid the continued repetition of this process in frontier areas by establishing a network of National Forests (Florestas Nacionais or Flonas) to stabilize the timber industry and simultaneously protect large tracts of forest. Flonas currently comprise less than 2% of the Brazilian Amazon (83,000 km(2)). If all these forests were used for sustainable logging, they would provide less than 10% of the demand for Amazonian timber. To sustainably supply the present and near-future demand for timber, approximately 700,000 km(2) of the Amazon forest needs to be brought into well-managed production. Brazil's National Forest Program, launched in 2000, is designed to create at least 400,000 km(2) of new Flonas. Objective decision-making tools are needed to site these new national forests. We present here a method for optimally locating the needed Flonas that incorporates information on existing protected areas, current vegetation cover, areas of human occupation, and timber stocks. The method combines these data in a spatial database that makes it possible to model the economic potential of the region's various forests as a function of their accessibility and timber values while constraining model solutions for existing areas of protection or human occupation. Our results indicate that 1.15 x 10(6) km(2) of forests (23% of the Brazilian Amazon) could be established as Flonas in a manner that will promote sustainable forest management; these Flonas would also serve as buffer zones for fully protected areas such as parks and reserves. | |||||
BibTeX:
@article{verissimo_priority_2002, author = {Verissimo, A. and Cochrane, M. A. and Souza, C. and Salomao, R.}, title = {Priority areas for establishing national forests in the Brazilian Amazon}, journal = {Conservation Ecology}, year = {2002}, volume = {6}, number = {1}, url = {://WOS:000177892600012} } |
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Verissimo, A., Cochrane, M.A. and Souza, C. | Ecology - National forests in the Amazon [BibTeX] |
2002 | Science Vol. 297(5586), pp. 1478-1478 |
article | DOI URL |
BibTeX:
@article{verissimo_ecology_2002, author = {Verissimo, A. and Cochrane, M. A. and Souza, C.}, title = {Ecology - National forests in the Amazon}, journal = {Science}, year = {2002}, volume = {297}, number = {5586}, pages = {1478--1478}, note = {Edition: 2002/08/31}, url = {://WOS:000177697300028}, doi = {https://doi.org/10.1126/science.1072807} } |
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Verissimo, A. and Cochrane, M.A. | A risky forest policy in the Amazon? Response [BibTeX] |
2003 | Science Vol. 299(5614), pp. 1843-1843 |
article | URL |
BibTeX:
@article{verissimo_risky_2003, author = {Verissimo, A. and Cochrane, M. A.}, title = {A risky forest policy in the Amazon? Response}, journal = {Science}, year = {2003}, volume = {299}, number = {5614}, pages = {1843--1843}, url = {://WOS:000181669700018} } |
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Verchot, L.V., Moutinho, P.R. and Davidson, D.A. | Leaf-cutting ant (Atta Sexdens) and nutrient cycling: deep soil inorganic nitrogen stocks, mineralization, and nitrification in Eastern Amazonia | 2003 | Soil Biology & Biochemistry Vol. 35(9), pp. 1219-1222 |
article | DOI URL |
Abstract: Nest excavation and agricultural activities of the leaf-cutting ant Atta sexdens create complex belowground heterogeneity in secondary forests of Eastern Amazonia. We examined the effects of this heterogeneity on inorganic-N stocks, net mineralization, and net nitrification to test the hypothesis that the bulk soil of the nests has higher net rates of mineralization and nitrification than soil that was not affected by the influences of ant nests, throughout the profile. This study was conducted in a secondary forest at Fazenda Vitoria, near Paragominas in the Eastern Brazilian Amazon, where a previous study showed that the bulk soil of ant nests had elevated NO3-. The results of the inorganic-N measurements were consistent with the previous study, showing elevated NO3- deep in the soil profile of the nests. However, neither net mineralization nor net nitrification were significantly greater at depth in the mineral soil of the nests compared to soil that was not influenced by nests (P = 0.05), although variability was higher in the nest soil. These results suggest that the NO3- may have diffused into the surrounding mineral from the N-rich organic matter buried by the ants in chambers within the deep soil. (C) 2003 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{verchot_leaf-cutting_2003, author = {Verchot, L. V. and Moutinho, P. R. and Davidson, D. A.}, title = {Leaf-cutting ant (Atta Sexdens) and nutrient cycling: deep soil inorganic nitrogen stocks, mineralization, and nitrification in Eastern Amazonia}, journal = {Soil Biology & Biochemistry}, year = {2003}, volume = {35}, number = {9}, pages = {1219--1222}, url = {://WOS:000184666300008}, doi = {https://doi.org/10.1016/s0038-0717(03)00183-4} } |
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Verchot, L.V., Davidson, E.A., Cattanio, J.H., Ackerman, I.L., Erickson, H.E. and Keller, M. | Land use change and biogeochemical controls of nitrogen oxide emissions from soils in eastern Amazonia | 1999 | Global Biogeochemical Cycles Vol. 13(1), pp. 31-46 |
article | DOI URL |
Abstract: The objectives of this study were (1) to determine the effects of land use change on N oxide fluxes from soil in seasonally dry, eastern Amazonia and (2) evaluate the "hole-in-the-pipe" model in a field setting where N availability varies among land uses and soil moisture varies among seasons. We measured N oxide flux from an old-growth forest, a 20-year-old secondary forest, an active pasture, and a degraded pasture. We also measured soil water content, soil inorganic N stocks, net N mineralization and nitrification potential. To determine the effects of pasture age on N oxide flux, we measured gas fluxes at a chronosequence of pastures (0-13 years). In the land use study, N(2)O fluxes followed the order: primary forest (2.4 kg N ha(-1) yr(-1)) textgreater secondary forest (0.9 kg N ha(-1) yr(-1)) textgreater active pasture (0.3 kg N ha(-1) yr(-1)) textgreater degraded pasture (0.1 kg N ha(-1) yr(-1)), and NO fluxes followed the order: primary forest (1.5 kg N ha(-1) yr(-1)) textgreater degraded pasture (0.7 kg N ha(-1) yr(-1)) 2 active pasture (0.5 kg N ha(-1) yr(-1)) 2 secondary forest (0.3 kg N ha(-1) yr(-1)). In the chronosequence study, no trend in N oxide emissions with pasture age was apparent, but emissions from pastures were lower than from the forest. Total N oxide flux correlated with a laboratory measure of nitrification potential (r(2) = 0.85). The ratio N(2)O:NO correlated with soil water content (r(2) = 0.56). Parameterization of the model accounted for variability in N oxide emissions across land uses and seasons and the model application revealed the importance of studying both N oxide gases simultaneously. Model predictions for six independent sites agreed well with observed fluxes, suggesting that the model may be applicable at a broader scale. The consistently low annual emissions of N(2)O estimated for all of the Amazonian pastures that we studied suggest that conversions of tropical forests to cattle pastures may not in the long term cause a significant increase in the contribution of soil emissions to atmospheric N(2)O or NO. | |||||
BibTeX:
@article{verchot_land_1999, author = {Verchot, L. V. and Davidson, E. A. and Cattanio, J. H. and Ackerman, I. L. and Erickson, H. E. and Keller, M.}, title = {Land use change and biogeochemical controls of nitrogen oxide emissions from soils in eastern Amazonia}, journal = {Global Biogeochemical Cycles}, year = {1999}, volume = {13}, number = {1}, pages = {31--46}, url = {://WOS:000079003000004}, doi = {https://doi.org/10.1029/1998gb900019} } |
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Verchot, L.V., Davidson, E.A., Cattanio, J.H. and Ackerman, I.L. | Land-use change and biogeochemical controls of methane fluxes in soils of eastern Amazonia | 2000 | Ecosystems Vol. 3(1), pp. 41-56 |
article | DOI URL |
Abstract: Tropical soils account for 10%-20% of the 15-35 Tg of atmospheric methane (CH(4)) consumed annually by soils, although tropical deforestation could be changing the soil sink. The objectives of this study were (a) to quantify differences in soil CH(4) fluxes among primary forest, secondary forest, arrive pasture, and degraded pasture in eastern Amazonia; and (b) to investigate controlling mechanisms of CH(4) fluxes, including N availability, gas-phase transport, and soil respiration. At one ranch, Fazenda Vitoria, annual uptake estimates (kg CH(4)ha(-1) y(-1)) based on monthly measurements were: primary forest, 2.1; secondary forest, 1.0; active pasture, 1.3; degraded pasture, 3.1. The lower annual uptake in the active pasture compared with the primary forest was due to CH(4) production during the wet season in the pasture soils, which is consistent with findings from other studies. In contrast, the degraded pasture was never a CH(4) source. Expressing uptake as a negative flux and emission as a positive flux, CH(4) fluxes were positively correlated with CO(2) fluxes, indicating that root and microbial respiration in the productive pastures, and to a lesser extent in the primary forest, contributed to the formation of anaerobic microsites where CH(4) was produced, whereas this productivity was absent in the degraded pasture. In all land uses, uptake rates of atmospheric CH(4) were greater in the dry season than in the wet season, indicating the importance of soil water content and gas transport on CH(4) fluxes. These clay soils had low annual uptake rates relative to reported rates on sandy soils, which also is consistent with gas transport within the soil being a limiting factor. Nitrogen availability indices did not correlate with CH(4) fluxes, indicating that inhibition of CH(4) oxidation was not an important mechanism explaining differences among land uses. At another ranch, Fazenda Agua Parada, no significant effect of pasture age was observed along a chronosequence of pasture ages. We conclude that land-use change can either increase or decrease the soil sink of CH(4), depending on the duration of wet and dry seasons, the effects of seasonal precipitation on gas-phase transport, and the phenology and relative productivity of the vegetation in each land use. | |||||
BibTeX:
@article{verchot_land-use_2000, author = {Verchot, L. V. and Davidson, E. A. and Cattanio, J. H. and Ackerman, I. L.}, title = {Land-use change and biogeochemical controls of methane fluxes in soils of eastern Amazonia}, journal = {Ecosystems}, year = {2000}, volume = {3}, number = {1}, pages = {41--56}, url = {://WOS:000085509300009}, doi = {https://doi.org/10.1007/s100210000009} } |
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Verchot, L.V., Brienza Jr., S., de Oliveira, V.C., Mutegi, J.K., Cattanio, J.H. and Davidson, E.A. | Fluxes of CH(4), CO(2), NO, and N(2)O in an improved fallow agroforestry system in eastern Amazonia | 2008 | Agriculture Ecosystems & Environment Vol. 126(1-2), pp. 113-121 |
article | DOI URL |
Abstract: The objective of this study was to evaluate the effect of leguminous fallows on methane (CH(4)), carbon dioxide (CO(2)), N oxides (N(2)O and NO) fluxes. We measured CH(4), N(2)O, NO, and CO(2) fluxes from improved fallows of Inga edulis and Acacia mangium during two successive fallow periods in an old agricultural frontier on sandy soils in eastern Amazonia. Sampling for the first fallow period was done in 1996 and 1997 while that for the second fallow was done in 1999 and 2000. We observed net CH(4) uptake during majority of the sampling campaigns. We did not observe any significant difference in CH(4) flux between improved fallows and unimproved fallows (control) during either of the sampling periods (P textgreater 0.05). We observed significantly higher uptake during the dry season relative to wet season, indicating the importance of soil water content and gas transport on CH(4) fluxes. For both wet and dry seasons, soil respiration rates (CO(2)) N(2)O and NO fluxes were similar for improved fallow plots and the control (P textgreater 0.05). We did not observe any significant seasonality in soil respiration or NO fluxes, but there was a significant difference in N(2)O flux between seasons (P = 0.0638). Contrary to other studies, our observations suggest that improved fallows using N-fixing trees do not appear to decrease the soil CH(4) sink and also do not seem to increase CO(2) and N-oxide emission in these sandy Amazonian soils. The result for N oxides is particularly pertinent to greenhouse gas (GHG) accounting methods that assess N(2)O emissions as a fraction of N fixation. (c) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{verchot_fluxes_2008, author = {Verchot, Louis V. and Brienza, Jr., Silvio and de Oliveira, Valdirene Costa and Mutegi, James K. and Cattanio, J. Henrique and Davidson, Eric A.}, title = {Fluxes of CH(4), CO(2), NO, and N(2)O in an improved fallow agroforestry system in eastern Amazonia}, journal = {Agriculture Ecosystems & Environment}, year = {2008}, volume = {126}, number = {1-2}, pages = {113--121}, url = {://WOS:000255694700011}, doi = {https://doi.org/10.1016/j.agee.2008.01.012} } |
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Vera-Diaz, M.d.C., Kaufmann, R.K., Nepstad, D.C. and Schlesinger, P. | An interdisciplinary model of soybean yield in the Amazon Basin: The climatic, edaphic, and economic determinants | 2008 | Ecological Economics Vol. 65(2), pp. 420-431 |
article | DOI URL |
Abstract: Soybean production is one of the main economic forces driving the expansion of the agricultural frontier in the Brazilian Amazon. To assess the potential for expansion we estimate a model of soybean yield that integrates the major climatic, edaphic, and economic determinants in the Amazon Basin. Yield is modeled as a function of yield as simulated by a crop physiology model that captures the effects of climate and physical attributes on the development of soybean plant; fertilizer applications; and economic/spatial parameters such as credit, transports costs and latitude. Current values of these determinants indicate that roughly 20% of Amazon Region or similar to 1,000,000 km(2) (excluding protected areas) can generate yields greater than 2000 kg/ha. Soybean production may be possible over a wider area of Amazon, but realizing this potential requires improvements in economic determinants such as the transportation infrastructure. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{vera-diaz_interdisciplinary_2008, author = {Vera-Diaz, Maria del Carmen and Kaufmann, Robert K. and Nepstad, Daniel C. and Schlesinger, Peter}, title = {An interdisciplinary model of soybean yield in the Amazon Basin: The climatic, edaphic, and economic determinants}, journal = {Ecological Economics}, year = {2008}, volume = {65}, number = {2}, pages = {420--431}, url = {://WOS:000254798800022}, doi = {https://doi.org/10.1016/j.ecolecon.2007.07.015} } |
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Venturini, A.M., Dias, N.M.S., Gontijo, J.B., Yoshiura, C.A., Paula, F.S., Meyer, K.M., Nakamura, F.M., da Franca, A.G., Borges, C.D., Barlow, J., Berenguer, E., Nusslein, K., Rodrigues, J.L.M., Bohannan, B.J.M. and Tsai, S.M. | Increased soil moisture intensifies the impacts of forest-to-pasture conversion on methane emissions and methane-cycling communities in the Eastern Amazon [BibTeX] |
2022 | Environ Res Vol. 212(Pt A), pp. 113139 |
article | DOI URL |
BibTeX:
@article{venturini_increased_2022, author = {Venturini, A. M. and Dias, N. M. S. and Gontijo, J. B. and Yoshiura, C. A. and Paula, F. S. and Meyer, K. M. and Nakamura, F. M. and da Franca, A. G. and Borges, C. D. and Barlow, J. and Berenguer, E. and Nusslein, K. and Rodrigues, J. L. M. and Bohannan, B. J. M. and Tsai, S. M.}, title = {Increased soil moisture intensifies the impacts of forest-to-pasture conversion on methane emissions and methane-cycling communities in the Eastern Amazon}, journal = {Environ Res}, year = {2022}, volume = {212}, number = {Pt A}, pages = {113139}, note = {Edition: 2022/03/27}, url = {https://www.ncbi.nlm.nih.gov/pubmed/35337832}, doi = {https://doi.org/10.1016/j.envres.2022.113139} } |
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Vendrasco, E.P., Dias, P.L.S. and Freitas, E.D. | A case study of the direct radiative effect of biomass burning aerosols on precipitation in the Eastern Amazon | 2009 | Atmospheric Research Vol. 94(3), pp. 409-421 |
article | DOI URL |
Abstract: Numerical experiments with the Brazilian additions to the Regional Atmospheric Modeling System were performed with two nested grids (50 and 10 km horizontal resolution, respectively) with and without the effect of biomass burning for 8 different situations for 96 h integrations. Only the direct radiative effect of aerosols is considered. The results were analyzed in large areas encompassing the BR163 road (one of the main areas of deforestation in the Amazon). mainly where most of the burning takes place. The precipitation change due to the direct radiative impact of biomass burning is generally negative (i.e., there is a decrease of precipitation). However, there are a few cases with a positive impact. Two opposite forcing mechanisms were explored: (a) the thermodynamic forcing that is generally negative in the sense that the aerosol tends to stabilize the lower atmosphere and (b) the dynamic impact associated with the low level horizontal pressure gradients produced by the aerosol plumes. In order to understand the non-linear relationship between the two effects, experiments were performed with 4-fold emissions. In these cases, the dynamic effect overcomes the stabilization produced by the radiative forcing and precipitation increase is observed in comparison with the control experiment. This study suggests that. in general, the biomass burning radiative forcing decreases the precipitation. However, very large concentrations of aerosols may lead to an increase of precipitation due to the dynamical forcing associated with the horizontal pressure gradients. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{vendrasco_case_2009, author = {Vendrasco, E. P. and Dias, P. L. Silva and Freitas, E. D.}, title = {A case study of the direct radiative effect of biomass burning aerosols on precipitation in the Eastern Amazon}, journal = {Atmospheric Research}, year = {2009}, volume = {94}, number = {3}, pages = {409--421}, url = {://WOS:000271336300005}, doi = {https://doi.org/10.1016/j.atmosres.2009.06.016} } |
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Vasconcelos, S.S., Zarin, D.J., Silva da Rosa, M.B. and Oliveira, F.d.A. | Leaf decomposition in a dry season irrigation experiment in Eastern Amazonian forest regrowth | 2007 | Biotropica Vol. 39(5), pp. 593-600 |
article | DOI URL |
Abstract: Leaf-litter decomposition is a major component of carbon and nutrient dynamics in tropical forest ecosystems, and moisture availability is widely considered to be a major influence on decomposition rates. Here, we report the results of a study of leaf-litter decomposition of five tree species in response to dry-season irrigation in a tropical forest regrowth stand in the Brazilian Amazon; three experiments differing in the timing of installation and duration allowed for an improved resolution of irrigation effects on decomposition. We hypothesized that decomposition rates would be faster under higher moisture availability in the wet season and during dry-season irrigation periods in the treatment plots, and that decomposition rates would be faster for species with higher quality leaves, independent of treatment. The rates of decomposition (k) were up to 2.4 times higher in irrigated plots than in control plots. The highest k values were shown by Annona paludosa (0.97 to 1.26/yr) while Ocotea guianensis (0.73 to 0.85/yr) had the lowest values; intermediate rates were found for Lacistema pubescens (0.91 to 1.02/yr) and Vismia guianensis (0.91 to 1.08/yr). These four tree species differed significantly in leaf-litter quality parameters (nitrogen, phosphorus, lignin, and cellulose concentrations, as well as lignin:nitrogen and carbon:nitrogen ratios), but differences in decomposition rates among tree species were not strictly correlated with leaf-litter quality. Overall, our results show that dry-season moisture deficits limit decomposition in Amazonian forest regrowth. | |||||
BibTeX:
@article{vasconcelos_leaf_2007, author = {Vasconcelos, Steel Silva and Zarin, Daniel Jacob and Silva da Rosa, Maria Beatriz and Oliveira, Francisco de Assis}, title = {Leaf decomposition in a dry season irrigation experiment in Eastern Amazonian forest regrowth}, journal = {Biotropica}, year = {2007}, volume = {39}, number = {5}, pages = {593--600}, url = {://WOS:000248968200006}, doi = {https://doi.org/10.1111/j.1744-7429.2007.00313.x} } |
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Vasconcelos, S.S., Zarin, D.J., Capanu, M., Littell, R., Davidson, E.A., Ishida, F.Y., Santos, E.B., Araujo, M.M., Aragao, D.V., Rangel-Vasconcelos, L.G.T., Oliveira, F.D., McDowell, W.H. and de Carvalho, C.J.R. | Moisture and substrate availability constrain soil trace gas fluxes in an eastern Amazonian regrowth forest | 2004 | Global Biogeochemical Cycles Vol. 18(2) |
article | DOI URL |
Abstract: Changes in land-use and climate are likely to alter moisture and substrate availability in tropical forest soils, but quantitative assessment of the role of resource constraints as regulators of soil trace gas fluxes is rather limited. The primary objective of this study was to quantify the effects of moisture and substrate availability on soil trace gas fluxes in an Amazonian regrowth forest. We measured the efflux of carbon dioxide (CO(2)), nitric oxide (NO), nitrous oxide (N(2)O), and methane (CH(4)) from soil in response to two experimental manipulations. In the first, we increased soil moisture availability during the dry season by irrigation; in the second, we decreased substrate availability by continuous removal of aboveground litter. In the absence of irrigation, soil CO(2) efflux decreased during the dry season while irrigation maintained soil CO(2) efflux levels similar to the wet season. Large variations in soil CO(2) efflux consistent with a significant moisture constraint on respiration were observed in response to soil wet-up and dry-down events. Annual soil C efflux for irrigated plots was 27 and 13% higher than for control plots in 2001 and 2002, respectively. Litter removal significantly reduced soil CO(2) efflux; annual soil C efflux in 2002 was 28% lower for litter removal plots compared to control plots. The annual soil C efflux: litterfall C ratio for the control treatment (4.0-5.2) was consistent with previously reported values for regrowth forests that indicate a relatively large belowground C allocation. In general, fluxes of N(2)O and CH(4) were higher during the wet season and both fluxes increased during dry-season irrigation. There was no seasonal effect on NO fluxes. Litter removal had no significant impact on N oxide or CH(4) emissions. Net soil nitrification did not respond to dry-season irrigation, but was somewhat reduced by litter removal. Overall, these results demonstrate significant soil moisture and substrate constraints on soil trace gas emissions, particularly for CO(2), and suggest that climate and land-use changes that alter moisture and substrate availability are therefore likely to have an impact on atmosphere chemistry. | |||||
BibTeX:
@article{vasconcelos_moisture_2004, author = {Vasconcelos, S. S. and Zarin, D. J. and Capanu, M. and Littell, R. and Davidson, E. A. and Ishida, F. Y. and Santos, E. B. and Araujo, M. M. and Aragao, D. V. and Rangel-Vasconcelos, L. G. T. and Oliveira, F. D. and McDowell, W. H. and de Carvalho, C. J. R.}, title = {Moisture and substrate availability constrain soil trace gas fluxes in an eastern Amazonian regrowth forest}, journal = {Global Biogeochemical Cycles}, year = {2004}, volume = {18}, number = {2}, url = {://WOS:000221611000002}, doi = {https://doi.org/10.1029/2003gb002210} } |
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Vasconcelos, S.S., Zarin, D.J., Araujo, M.M., Turbay Rangel-Vasconcelos, L.G., Reis de Carvalho, C.J., Staudhammer, C.L. and Oliveirat, F.d.A. | Effects of seasonality, litter removal and dry-season irrigation on litterfall quantity and quality in eastern Amazonian forest regrowth, Brazil | 2008 | Journal of Tropical Ecology Vol. 24, pp. 27-38 |
article | DOI URL |
Abstract: Litterfall quantity and quality may respond to alterations in resource availability expected with ongoing land-use and climate changes. Here, we quantify the effects of altered resource availability on non-woody litterfall quantity and quality (nitrogen and phosphorus concentrations) in eastern Amazonian forest regrowth (Brazil) through two multi-year experimental manipulations: (1) daily irrigation (5 mm d(-1)) during the dry season; and (2) fortnightly litter removal. Consistent with other tropical forest data litterfall exhibited seasonal patterns, increasing with the onset of the dry season and declining with the onset of the rainy season. Irrigation did not affect litterfall mass and had little impact on nitrogen (N) or phosphorus (P) concentrations and return, except for decreasing litter P concentration at the end of two irrigation periods. Litter removal did not alter litterfall mass or P concentration, but progressively reduced litterfall N during the course of the experiment. Overall, these results suggest significant resistance to altered resource availability within the bounds of our experimental treatments; our findings may help to constrain carbon and nutrient cycling predictions for tropical forests in response to land-use and climate changes. | |||||
BibTeX:
@article{vasconcelos_effects_2008, author = {Vasconcelos, Steel Silva and Zarin, Daniel Jacob and Araujo, Maristela Machado and Turbay Rangel-Vasconcelos, Livia Gabrig and Reis de Carvalho, Claudio Jose and Staudhammer, Christina Lynn and Oliveirat, Francisco de Assis}, title = {Effects of seasonality, litter removal and dry-season irrigation on litterfall quantity and quality in eastern Amazonian forest regrowth, Brazil}, journal = {Journal of Tropical Ecology}, year = {2008}, volume = {24}, pages = {27--38}, url = {://WOS:000252822200004}, doi = {https://doi.org/10.1017/s0266467407004580} } |
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Vasconcelos, H.L. and Luizao, F.J. | Litter production and litter nutrient concentrations in a fragmented Amazonian landscape | 2004 | Ecological Applications Vol. 14(3), pp. 884-892 |
article | DOI URL |
Abstract: We analyzed the effects of distance to forest edge and soil texture on fine-litter production and on nutrient concentrations in the leaf fall in an experimentally fragmented landscape in Brazilian Amazonia. Production of fine litter (leaves, twigs textless2 cm in diameter, flowers, and fruits) was measured over a 3-yr period. Litter traps were installed in plots located near (textless100 m) and, far (textgreater250 m) from forest edges, and in clayey or sandy soils. In total, 28 plots were established, with 10 litter traps-per plot. Results reveal a significant effect of distance to forest edge on litter production, but no significant effect of soil type or interaction between soil type and edge distance. On average, annual litter production on edge plots exceeded that on the interior plots by 0.68 Mg/ha (9.50 +/- 0.23 vs. 8.82 +/- 0.14 Mg.ha(-1).yr(-1), mean +/- SE, based on a 3-yr period). With regard to nutrient concentrations in the leaf fall, we detected a significant effect of soil type on three of eight nutrients analyzed. Concentrations of N, Mg, and Mn were greater in leaves on clayey than on sandy soils. Distance to forest edge only significantly affected the concentration of Ca, which was greater near than far from edges, perhaps due to strong Ca mobilization by the roots of pioneer trees. Several factors may account for the observed increase in litterfall near forest edges, including the greater prevalence of winds, increased plant desiccation stress, and higher rates of tree recruitment, especially of pioneer trees, near edges. Elevated rates of litterfall are likely to have cascading effects on the ecology of fragmented forests, affecting the invertebrate fauna, increasing seed and seedling mortality, and causing forest fragments to be more vulnerable to destructive surface fires. | |||||
BibTeX:
@article{vasconcelos_litter_2004, author = {Vasconcelos, H. L. and Luizao, F. J.}, title = {Litter production and litter nutrient concentrations in a fragmented Amazonian landscape}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {3}, pages = {884--892}, url = {://WOS:000222174000020}, doi = {https://doi.org/10.1890/03-5093} } |
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Vasconcelos, H.L. and Laurance, W.F. | Influence of habitat, litter type, and soil invertebrates on leaf-litter decomposition in a fragmented Amazonian landscape | 2005 | Oecologia Vol. 144(3), pp. 456-462 |
article | DOI URL |
Abstract: Amazonian forest fragments and second-growth forests often differ substantially from undisturbed forests in their microclimate, plant-species composition, and soil fauna. To determine if these changes could affect litter decomposition, we quantified the mass loss of two contrasting leaf-litter mixtures, in the presence or absence of soil macroinvertebrates, and in three forest habitats. Leaf-litter decomposition rates in second-growth forests (textgreater 10 years old) and in fragment edges (textless 100 m from the edge) did not differ from that in the forest interior (textgreater 250 in from the edges of primary forests). In all three habitats, experimental exclusion of soil invertebrates resulted in slower decomposition rates. Faunal-exclosure effects were stronger for litter of the primary forest, composed mostly of leaves of old-growth trees, than for litter of second-growth forests, which was dominated by leaves of successional species. The latter had a significantly lower initial concentration of N, higher C:N and lignin:N ratios, and decomposed at a slower rate than did litter from forest interiors. Our results indicate that land-cover changes in Amazonia affect decomposition mainly through changes in plant species composition, which in turn affect litter quality. Similar effects may occur on fragment edges, particularly on very disturbed edges, where successional trees become dominant. The drier microclimatic conditions in fragment edges and second-growth forests (textgreater10 years old) did not appear to inhibit decomposition. Finally, although soil invertebrates play a key role in leaf-litter decomposition, we found no evidence that differences in the abundance, species richness, or species composition of invertebrates between disturbed and undisturbed forests significantly altered decomposition rates. | |||||
BibTeX:
@article{vasconcelos_influence_2005, author = {Vasconcelos, H. L. and Laurance, W. F.}, title = {Influence of habitat, litter type, and soil invertebrates on leaf-litter decomposition in a fragmented Amazonian landscape}, journal = {Oecologia}, year = {2005}, volume = {144}, number = {3}, pages = {456--462}, note = {Edition: 2005/06/09}, url = {://WOS:000231247800013}, doi = {https://doi.org/10.1007/s00442-005-0117-1} } |
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Vasconcelos, C. and Novo, E. | Mapeamento do uso e cobertura da terra a partir da segmentação e classificação de imagens- fração solo, sombra e vegetação derivadas do modelo linear de mistura aplicado a dados sdo sensor TM/Landsat 5, na região do reservatório de Tucuruí/PA [BibTeX] |
2004 | Acta Amazonica Vol. 34, pp. 487-493 |
article | |
BibTeX:
@article{vasconcelos_mapeamento_2004, author = {Vasconcelos, C.H. and Novo, E.M.L.M.}, title = {Mapeamento do uso e cobertura da terra a partir da segmentação e classificação de imagens- fração solo, sombra e vegetação derivadas do modelo linear de mistura aplicado a dados sdo sensor TM/Landsat 5, na região do reservatório de Tucuruí/PA}, journal = {Acta Amazonica}, year = {2004}, volume = {34}, pages = {487--493} } |
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Varella, R.F., Bustamante, M.M.C., Pinto, A.S., Kisselle, K.W., Santos, R.V., Burke, R.A., Zepp, R.G. and Viana, L.T. | Soil fluxes of CO(2), CO, NO, And N(2)O from an old pasture and from native Savanna in Brazil | 2004 | Ecological Applications Vol. 14(4), pp. S221-S231 |
article | URL |
Abstract: We compared fluxes Of CO(2), CO, NO, and N(2)O, soil microbial biomass,and N availability in a 20-yr-old Brachiaria pasture and a native cerrado area (savanna in central Brazil). Availability of N and NO fluxes were lower in the pasture than in the cerrado. N(2)O fluxes were below detection limit at both sites. The CO fluxes showed weak seasonal variation with slightly higher positive fluxes in the dry season and lower fluxes, including net consumption, during the wet season. The cerrado CO fluxes were higher and more variable than the fluxes in the pasture. Both sites showed a seasonal pattern in CO(2) emissions with lower fluxes (similar to2 mumol CO(2)(.)m(-2.)s(-2) 1) during the dry season. There were no significant differences in annual CO(2) soil emissions between the cerrado and the pasture, but the temporal trends differed, with higher fluxes in the pasture during the transition from the wet to the dry season. Artificial water addition in the pasture during the dry season resulted in short-lived pulses of NO and CO(2). | |||||
BibTeX:
@article{varella_soil_2004, author = {Varella, R. F. and Bustamante, M. M. C. and Pinto, A. S. and Kisselle, K. W. and Santos, R. V. and Burke, R. A. and Zepp, R. G. and Viana, L. T.}, title = {Soil fluxes of CO(2), CO, NO, And N(2)O from an old pasture and from native Savanna in Brazil}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S221--S231}, url = {://WOS:000223269000019} } |
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VanWey, L.K., D'Antona, A.O. and Brondizio, E.S. | Household demographic change and land use/land cover change in the Brazilian Amazon | 2007 | Population and Environment Vol. 28(3), pp. 163-185 |
article | DOI URL |
Abstract: Demographic interest in population and environment has grown in recent decades. One of the most prominent research areas in this tradition addresses the impact of population on land use and land cover change. Building on this tradition, we examine the effects of household demographic composition on land use and land cover on small farms in two study areas in the Brazilian Amazon. Fixed effects regression models of used area and forested area show few consistent effects of changes in household demography on land use and land cover change. Effects are inconsistent with the household life cycle model that currently dominates the literature on household demographic effects in frontiers. Changes in the number of children and women, particularly young women, have the most significant effects on land use and land cover change. We conclude by arguing that households strategically access cash for investment in agriculture and that specific strategies are determined by economic and institutional context. | |||||
BibTeX:
@article{vanwey_household_2007, author = {VanWey, Leah K. and D'Antona, Alvaro O. and Brondizio, Eduardo S.}, title = {Household demographic change and land use/land cover change in the Brazilian Amazon}, journal = {Population and Environment}, year = {2007}, volume = {28}, number = {3}, pages = {163--185}, url = {://WOS:000247585200002}, doi = {https://doi.org/10.1007/s11111-007-0040-y} } |
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van Haren, J.L.M., Cosme de Oliveira Jr., R., Restrepo-Coupe, N., Hutyra, L., de Camargo, P.B., Keller, M. and Saleska, S.R. | Do plant species influence soil CO(2) and N(2)O fluxes in a diverse tropical forest? | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115(G3) |
article | DOI URL |
Abstract: To test whether plant species influence greenhouse gas production in diverse ecosystems, we measured wet season soil CO(2) and N(2)O fluxes close to similar to 300 large (textgreater35 cm in diameter at breast height (DBH)) trees of 15 species at three clay-rich forest sites in central Amazonia. We found that soil CO(2) fluxes were 38% higher near large trees than at control sites textgreater10 m away from any tree (P textless 0.0001). After adjusting for large tree presence, a multiple linear regression of soil temperature, bulk density, and liana DBH explained 19% of remaining CO(2) flux variability. Soil N(2)O fluxes adjacent to Caryocar villosum, Lecythis lurida, Schefflera morototoni, and Manilkara huberi were 84%-196% greater than Erisma uncinatum and Vochysia maxima, both Vochysiaceae. Tree species identity was the most important explanatory factor for N(2)O fluxes, accounting for more than twice the N(2)O flux variability as all other factors combined. Two observations suggest a mechanism for this finding: (1) sugar addition increased N(2)O fluxes near C. villosum twice as much (P textless 0.05) as near Vochysiaceae and (2) species mean N(2)O fluxes were strongly negatively correlated with tree growth rate (P = 0.002). These observations imply that through enhanced belowground carbon allocation liana and tree species can stimulate soil CO(2) and N(2)O fluxes (by enhancing denitrification when carbon limits microbial metabolism). Alternatively, low N(2)O fluxes potentially result from strong competition of tree species with microbes for nutrients. Species-specific patterns in CO(2) and N(2)O fluxes demonstrate that plant species can influence soil biogeochemical processes in a diverse tropical forest. | |||||
BibTeX:
@article{van_haren_plant_2010, author = {van Haren, Joost L. M. and Cosme de Oliveira, Jr., R. and Restrepo-Coupe, Natalia and Hutyra, Lucy and de Camargo, Plinio B. and Keller, Michael and Saleska, Scott R.}, title = {Do plant species influence soil CO(2) and N(2)O fluxes in a diverse tropical forest?}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, number = {G3}, url = {://WOS:000280718800001}, doi = {https://doi.org/10.1029/2009jg001231} } |
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van Gorsel, E., Delpierre, N., Leuning, R., Black, A., Munger, J.W., Wofsy, S., Aubinet, M., Feigenwinter, C., Beringer, J., Bonal, D., Chen, B., Chen, J., Clement, R., Davis, K.J., Desai, A.R., Dragoni, D., Etzold, S., Gruenwald, T., Gu, L., Heinesch, B., Hutyra, L.R., Jans, W.W.P., Kutsch, W., Law, B.E., Leclerc, M.Y., Mammarella, I., Montagnani, L., Noormets, A., Rebmann, C. and Wharton, S. | Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO(2) | 2009 | Agricultural and Forest Meteorology Vol. 149(11), pp. 1919-1930 |
article | DOI URL |
Abstract: Micrometeorological measurements of night time ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u*-threshold filtering technique. Tellus 59B, 397-403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (F(C)) and change in storage (F(S)) of CO(2) in the few hours after sundown. The sum of F(C) and F(S) reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration R(Rmax). The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of F(c) + F(s) extrapolated to zero light, R(LRC), and (3) with a detailed process-based forest ecosystem model, R(cast). At most sites respiration rates estimated using the u*-filter, R(ust), were smaller than R(Rmax), and R(LRC). Agreement of our approach with independent measurements indicates that R(Rmax), provides an excellent estimate of nighttime ecosystem respiration. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{van_gorsel_estimating_2009, author = {van Gorsel, Eva and Delpierre, Nicolas and Leuning, Ray and Black, Andy and Munger, J. William and Wofsy, Steven and Aubinet, Marc and Feigenwinter, Christian and Beringer, Jason and Bonal, Damien and Chen, Baozhang and Chen, Jiquan and Clement, Robert and Davis, Kenneth J. and Desai, Ankur R. and Dragoni, Danilo and Etzold, Sophia and Gruenwald, Thomas and Gu, Lianhong and Heinesch, Bernhard and Hutyra, Lucy R. and Jans, Wilma W. P. and Kutsch, Werner and Law, B. E. and Leclerc, Monique Y. and Mammarella, Ivan and Montagnani, Leonardo and Noormets, Asko and Rebmann, Corinna and Wharton, Sonia}, title = {Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO(2)}, journal = {Agricultural and Forest Meteorology}, year = {2009}, volume = {149}, number = {11}, pages = {1919--1930}, url = {://WOS:000270640300013}, doi = {https://doi.org/10.1016/j.agrformet.2009.06.020} } |
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van Dijk, S.M., Gut, A., Kirkman, G.A., Meixner, F.X., Andreae, M.O. and Gomes, B.M. | Biogenic NO emissions from forest and pasture soils: Relating laboratory studies to field measurements | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: During September and October 1999, dynamic chamber measurements were carried out to determine nitric oxide (NO) fluxes from a primary forest soil and an old pasture in the Brazilian Amazon basin as part of the project "European Studies of Trace Gases and Atmospheric Chemistry as a Contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia" (LBA-EUSTACH). In addition, soil samples were collected from these two sites, and laboratory experiments were conducted to determine the NO production and consumption rate constants as functions of soil temperature and soil moisture. These laboratory results were converted into NO fluxes using a simple algorithm, which required additional information on the gas diffusion in soil, the soil bulk density, and the field conditions (soil temperature and soil moisture). Over the entire measurement period, the calculated and measured NO fluxes agreed well both for the forest (6.9 +/- 2.9 and 5.0 +/- 4.6 ng m(-2) s(-1), respectively) and for the pasture (0.67 +/- 0.09 and 0.65 +/- 0.37 ng m(-2) s(-1), respectively). Forest to pasture conversion decreased NO production and gas diffusion and resulted in smaller NO fluxes from pasture than forest soil. | |||||
BibTeX:
@article{van_dijk_biogenic_2002, author = {van Dijk, S. M. and Gut, A. and Kirkman, G. A. and Meixner, F. X. and Andreae, M. O. and Gomes, B. M.}, title = {Biogenic NO emissions from forest and pasture soils: Relating laboratory studies to field measurements}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200015 http://www.agu.org/journals/jd/jd0217/2001JD000358/2001JD000358.pdf}, doi = {https://doi.org/10.1029/2001jd000358} } |
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van der Werf, G.R., Morton, D.C., DeFries, R.S., Olivier, J.G.J., Kasibhatla, P.S., Jackson, R.B., Collatz, G.J. and Randerson, J.T. | CO(2) emissions from forest loss [BibTeX] |
2009 | Nature Geoscience Vol. 2(11), pp. 737-738 |
article | DOI URL |
BibTeX:
@article{van_der_werf_co2_2009, author = {van der Werf, G. R. and Morton, D. C. and DeFries, R. S. and Olivier, J. G. J. and Kasibhatla, P. S. and Jackson, R. B. and Collatz, G. J. and Randerson, J. T.}, title = {CO(2) emissions from forest loss}, journal = {Nature Geoscience}, year = {2009}, volume = {2}, number = {11}, pages = {737--738}, url = {://WOS:000271388500004}, doi = {https://doi.org/10.1038/ngeo671} } |
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van der Werf, G.R., Morton, D.C., DeFries, R.S., Giglio, L., Randerson, J.T., Collatz, G.J. and Kasibhatla, P.S. | Estimates of fire emissions from an active deforestation region in the southern Amazon based on satellite data and biogeochemical modelling | 2009 | Biogeosciences Vol. 6(2), pp. 235-249 |
article | URL |
Abstract: Tropical deforestation contributes to the build-up of atmospheric carbon dioxide in the atmosphere. Within the deforestation process, fire is frequently used to eliminate biomass in preparation for agricultural use. Quantifying these deforestation-induced fire emissions represents a challenge, and current estimates are only available at coarse spatial resolution with large uncertainty. Here we developed a biogeochemical model using remote sensing observations of plant productivity, fire activity, and deforestation rates to estimate emissions for the Brazilian state of Mato Grosso during 2001-2005. Our model of DEforestation CArbon Fluxes (DECAF) runs at 250-m spatial resolution with a monthly time step to capture spatial and temporal heterogeneity in fire dynamics in our study area within the "arc of deforestation", the southern and eastern fringe of the Amazon tropical forest where agricultural expansion is most concentrated. Fire emissions estimates from our modelling framework were on average 90 Tg C year(-1), mostly stemming from fires associated with deforestation (74%) with smaller contributions from fires from conversions of Cerrado or pastures to cropland (19%) and pasture fires (7%). In terms of carbon dynamics, about 80% of the aboveground living biomass and litter was combusted when forests were converted to pasture, and 89% when converted to cropland because of the highly mechanized nature of the deforestation process in Mato Grosso. The trajectory of land use change from forest to other land uses often takes more than one year, and part of the biomass that was not burned in the dry season following deforestation burned in consecutive years. This led to a partial decoupling of annual deforestation rates and fire emissions, and lowered interannual variability in fire emissions. Interannual variability in the region was somewhat dampened as well because annual emissions from fires following deforestation and from maintenance fires did not covary, although the effect was small due to the minor contribution of maintenance fires. Our results demonstrate how the DECAF model can be used to model deforestation fire emissions at relatively high spatial and temporal resolutions. Detailed model output is suitable for policy applications concerned with annual emissions estimates distributed among post-clearing land uses and science applications in combination with atmospheric emissions modelling to provide constrained global deforestation fire emissions estimates. DECAF currently estimates emissions from fire; future efforts can incorporate other aspects of net carbon emissions from deforestation including soil respiration and regrowth. | |||||
BibTeX:
@article{van_der_werf_estimates_2009, author = {van der Werf, G. R. and Morton, D. C. and DeFries, R. S. and Giglio, L. and Randerson, J. T. and Collatz, G. J. and Kasibhatla, P. S.}, title = {Estimates of fire emissions from an active deforestation region in the southern Amazon based on satellite data and biogeochemical modelling}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {2}, pages = {235--249}, url = {://WOS:000263839200009} } |
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van der Molen, M.K., Dolman, A.J., Ciais, P., Eglin, T., Gobron, N., Law, B.E., Meir, P., Peters, W., Phillips, O.L., Reichstein, M., Chen, T., Dekker, S.C., Doubkova, M., Friedl, M.A., Jung, M., van den Hurk, B.J.J.M., de Jeu, R.A.M., Kruijt, B., Ohta, T., Rebel, K.T., Plummer, S., Seneviratne, S.I., Sitch, S., Teuling, A.J., van der Werf, G.R. and Wang, G. | Drought and ecosystem carbon cycling | 2011 | Agricultural and Forest Meteorology Vol. 151(7), pp. 765-773 |
article | DOI URL |
Abstract: Drought as an intermittent disturbance of the water cycle interacts with the carbon cycle differently than the 'gradual' climate change. During drought plants respond physiologically and structurally to prevent excessive water loss according to species-specific water use strategies. This has consequences for carbon uptake by photosynthesis and release by total ecosystem respiration. After a drought the disturbances in the reservoirs of moisture, organic matter and nutrients in the soil and carbohydrates in plants lead to longer-term effects in plant carbon cycling, and potentially mortality. Direct and carry-over effects, mortality and consequently species competition in response to drought are strongly related to the survival strategies of species. Here we review the state of the art of the understanding of the relation between soil moisture drought and the interactions with the carbon cycle of the terrestrial ecosystems. We argue that plant strategies must be given an adequate role in global vegetation models if the effects of drought on the carbon cycle are to be described in a way that justifies the interacting processes. (C) 2011 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{van_der_molen_drought_2011, author = {van der Molen, M. K. and Dolman, A. J. and Ciais, P. and Eglin, T. and Gobron, N. and Law, B. E. and Meir, P. and Peters, W. and Phillips, O. L. and Reichstein, M. and Chen, T. and Dekker, S. C. and Doubkova, M. and Friedl, M. A. and Jung, M. and van den Hurk, B. J. J. M. and de Jeu, R. A. M. and Kruijt, B. and Ohta, T. and Rebel, K. T. and Plummer, S. and Seneviratne, S. I. and Sitch, S. and Teuling, A. J. and van der Werf, G. R. and Wang, G.}, title = {Drought and ecosystem carbon cycling}, journal = {Agricultural and Forest Meteorology}, year = {2011}, volume = {151}, number = {7}, pages = {765--773}, url = {://WOS:000291283300001}, doi = {https://doi.org/10.1016/j.agrformet.2011.01.018} } |
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van der Heijden, G.M.F. and Phillips, O.L. | Environmental effects on Neotropical liana species richness | 2009 | Journal of Biogeography Vol. 36(8), pp. 1561-1572 |
article | DOI URL |
Abstract: Aim Lianas differ physiologically from trees, and therefore their species-richness patterns and potential climate-change responses might also differ. However, multivariate assessments of spatial patterns in liana species richness and their controls are lacking. Our aim in this paper is to identify the environmental factors that best explain the variation in liana species richness within tropical forests. Location Lowland and montane Neotropical forests. Methods We quantified the contributions of environmental variables and liana and tree-and-shrub abundance to the species richness of lianas, trees and shrubs textgreater= 2.5 cm in diameter using a subset of 65 standardized (0.1 ha) plots from 57 Neotropical sites from a global dataset collected by the late Alwyn Gentry. We used both regression and structural equation modelling to account for the effects of environmental variables (climate, soil and disturbance) and liana density on liana species richness, and we compared the species-richness patterns of lianas with those of trees and shrubs. Results We found that, after accounting for liana density, dry-season length was the dominant predictor of liana species richness. In addition, liana species richness was also related to stand-level wood density (a proxy for disturbance) in lowland forests, a pattern that has not hitherto been shown across such a large study region. Liana species richness had a weak association with soil properties, but the effect of soil may be obscured by the strong correlation between soil properties and climate. The diversity patterns of lianas and of trees and shrubs were congruent: wetter forests had a greater species richness of all woody plants. Main conclusions The primary association of both liana and tree-and-shrub species richness with water availability suggests that, if parts of the Neotropics become drier as a result of climate change, substantial declines in the species richness of woody plants at the stand level may be anticipated. | |||||
BibTeX:
@article{van_der_heijden_environmental_2009, author = {van der Heijden, Geertje M. F. and Phillips, Oliver L.}, title = {Environmental effects on Neotropical liana species richness}, journal = {Journal of Biogeography}, year = {2009}, volume = {36}, number = {8}, pages = {1561--1572}, url = {://WOS:000268056000013}, doi = {https://doi.org/10.1111/j.1365-2699.2009.02099.x} } |
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van der Heijden, G.M.F. and Phillips, O.L. | Liana infestation impacts tree growth in a lowland tropical moist forest | 2009 | Biogeosciences Vol. 6(10), pp. 2217-2226 |
article | URL |
Abstract: Ecosystem-level estimates of the effect of lianas on tree growth in mature tropical forests are needed to evaluate the functional impact of lianas and their potential to affect the ability of tropical forests to sequester carbon, but these are currently lacking. Using data collected on tree growth rates, local growing conditions and liana competition in five permanent sampling plots in Amazonian Peru, we present the first ecosystem-level estimates of the effect of lianas on above-ground productivity of trees. By first constructing a multi-level linear mixed effect model to predict individual-tree diameter growth model using individual-tree growth conditions, we were able to then estimate stand-level above-ground biomass (AGB) increment in the absence of lianas. We show that lianas, mainly by competing above-ground with trees, reduce tree annual above-ground stand-level biomass increment by similar to 10%, equivalent to 0.51 Mg dry weight ha(-1) yr(-1) or 0.25 Mg C ha(-1) yr(-1). AGB increment of lianas themselves was estimated to be 0.15 Mg dry weight ha(-1) yr(-1) or 0.07 Mg C ha(-1) yr(-1), thus only compensating similar to 29% of the liana-induced reduction in ecosystem AGB increment. Increasing liana pressure on tropical forests will therefore not only tend to reduce their carbon storage capacity, by indirectly promoting tree species with low-density wood, but also their rate of carbon uptake, with potential consequences for the rate of increase in atmospheric carbon dioxide. | |||||
BibTeX:
@article{van_der_heijden_liana_2009, author = {van der Heijden, G. M. F. and Phillips, O. L.}, title = {Liana infestation impacts tree growth in a lowland tropical moist forest}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {10}, pages = {2217--2226}, url = {://WOS:000271354900018} } |
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van der Heijden, G.M.F. and Phillips, O.L. | What controls liana success in Neotropical forests? | 2008 | Global Ecology and Biogeography Vol. 17(3), pp. 372-383 |
article | DOI URL |
Abstract: Aim We seek to determine the factors which control the success of lianas across macroecological gradients. Lianas have a strong impact on the growth, mortality and biomass of tropical trees, and are reported to be increasing in dominance, so understanding their behaviour is important from the perspectives of both ecological and global change. Location Lowland and montane Neotropical forests. Methods Using 65 standardized samples of lianas (textgreater= 2.5 cm diameter) from across the Neotropics, we attempted to account for characteristics of both the environment and the forest in explaining macroecological variation in liana success in Neotropical forests, using regression analyses and structural equation modelling. Results We found that both liana density and basal area were unrelated to mean annual precipitation, dry season length or soil variables, except for a weak effect of mean annual precipitation on liana basal area. Structural characteristics of the forest explained more of the variation in liana density and basal area than the physical environment. More disturbed forests generally tended to have a higher liana density. Liana basal area, however, was highest in undisturbed forests. Main conclusions The availability of host trees and their characteristics may be more important than the direct effects of the physical environment in controlling the success of lianas in Neotropical forests. Changes to the tropical climate in the coming century may not strongly affect lianas directly, but could have very substantial indirect effects via changes in tree community structure and dynamics. | |||||
BibTeX:
@article{van_der_heijden_what_2008, author = {van der Heijden, Geertje M. F. and Phillips, Oliver L.}, title = {What controls liana success in Neotropical forests?}, journal = {Global Ecology and Biogeography}, year = {2008}, volume = {17}, number = {3}, pages = {372--383}, url = {://WOS:000254948700007}, doi = {https://doi.org/10.1111/j.1466-8238.2007.00376.x} } |
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van der Heijden, G.M.F., Healey, J.R. and Phillips, O.L. | Infestation of trees by lianas in a tropical forest in Amazonian Peru | 2008 | Journal of Vegetation Science Vol. 19(6), pp. 747-U8 |
article | DOI URL |
Abstract: Question: In Amazonian moist forest, four questions arose: 1. Do tree species differ in their susceptibility to lianas? 2. What host tree traits (branch-free bole height, growth rate, bark type, leaf length and adult stature) are correlated with the susceptibility of tree species to lianas infesting the trunk and the crown? 3. To what extent do spatial variables (proximity to liana-infested trees and the light environment of the tree crown) affect the likelihood of liana infestation? 4. Are spatial variables or tree traits relatively more important in influencing the susceptibility of trees to lianas? We address all questions separately for trunk and crown infestation. Location: Tambopata Nature Reserve, Peru. Methods: We collected information on liana infestation, tree morphological traits, growth, light-environment and position for 3675 trees in seven 1-ha permanent sample plots. We separated trunk from crown infestation and used correlation and logistic regression analyses for tree species and individual tree-level analyses, respectively. Results: Half of all trees were colonised by at least one liana. Of 41 relatively common dicot tree species, at least five have significantly greater and three significantly lower crown infestation rates than expected by chance. Trunk and crown infestation are influenced by different host traits - trunk infestation was only affected by bark type, while crown infestation is reduced when trees are fast-growing, tall, have low-density wood, long branch-free boles and long leaves. The likelihood of both trunk and crown infestation increases for trees growing in close proximity to another liana-infested tree, but is invariant with the light environment of tree crowns. Conclusion: Crown and trunk infestation have not been properly distinguished before; it is important to do so as the factors determining the different modes of infestation differ fundamentally. The association between crown infestation and tree traits suggests that increases in liana dominance in Amazonian forests could cause changes in forest composition, including favouring faster growing tree species with low density wood, potentially reducing the carbon stored by mature forests. | |||||
BibTeX:
@article{van_der_heijden_infestation_2008, author = {van der Heijden, Geertje M. F. and Healey, John R. and Phillips, Oliver L.}, title = {Infestation of trees by lianas in a tropical forest in Amazonian Peru}, journal = {Journal of Vegetation Science}, year = {2008}, volume = {19}, number = {6}, pages = {747--U8}, url = {://WOS:000264001900002}, doi = {https://doi.org/10.3170/2008-8-18459} } |
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van der Heijden, G.M.F., Feldpausch, T.R., Herrero, A.d.l.F., van der Velden, N.K. and Phillips, O.L. | Calibrating the liana crown occupancy index in Amazonian forests | 2010 | Forest Ecology and Management Vol. 260(4), pp. 549-555 |
article | DOI URL |
Abstract: Lianas hold an important, but understudied, role in forest dynamics, however they are difficult to measure and detailed liana measurements are time consuming. Many researchers have therefore used an ordinal scale index, the crown occupancy index (COI), to describe the liana load carried by trees. Here we assess the overall effectiveness, in terms of accuracy, precision, repeatability and efficiency, of the COI in tropical forests. We relate the COI to more detailed liana measurements at the individual tree-level and site-level, comparing sites with different levels of liana infestation. Our results show (1) that the COI accurately measures individual tree and plot level liana loads, indicated by the strong correlations between the COI and the number and basal area of lianas. However, (2) as expected, the COI is only weakly related to the basal area of lianas rooted close to the tree, which is a proxy for competition for below-ground resources. The COI is also (3) an efficient measure of liana loads, as the input time needed for a COI survey is considerably less than that of a detailed liana survey. We also (4) found a high degree of repeatability in COI classification between observers. Additionally (5), the COI can be used to differentiate between sites in terms of their overall liana canopy competition (precision), but (6) may not be a precise indicator of the site-level mean basal area of lianas in tree crowns. (C) 2010 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{van_der_heijden_calibrating_2010, author = {van der Heijden, Geertje M. F. and Feldpausch, Ted R. and Herrero, Ana de la Fuente and van der Velden, Naomi K. and Phillips, Oliver L.}, title = {Calibrating the liana crown occupancy index in Amazonian forests}, journal = {Forest Ecology and Management}, year = {2010}, volume = {260}, number = {4}, pages = {549--555}, url = {://WOS:000280172400015}, doi = {https://doi.org/10.1016/j.foreco.2010.05.011} } |
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van Asperen, H., Alves-Oliveira, J.R., Warneke, T., Forsberg, B., de Araújo, A.C. and Notholt, J. | The role of termite CH4 emissions on the ecosystem scale: a case study in the Amazon rainforest [BibTeX] |
2021 | Biogeosciences Vol. 18(8), pp. 2609-2625 |
article | DOI URL |
BibTeX:
@article{van_asperen_role_2021, author = {van Asperen, H. and Alves-Oliveira, J. R. and Warneke, T. and Forsberg, B. and de Araújo, A. C. and Notholt, J.}, title = {The role of termite CH4 emissions on the ecosystem scale: a case study in the Amazon rainforest}, journal = {Biogeosciences}, year = {2021}, volume = {18}, number = {8}, pages = {2609--2625}, url = {https://bg.copernicus.org/articles/18/2609/2021/}, doi = {https://doi.org/10.5194/bg-18-2609-2021} } |
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Valentini, C.M.A., Sanches, L., de Paula, S.R., Vourlitis, G.L., de Souza Nogueira, J., Pinto, O.B. and de Almeida Lobo, F. | Soil respiration and aboveground litter dynamics of a tropical transitional forest in northwest Mato Grosso, Brazil | 2008 | Journal of Geophysical Research Vol. 113 |
article | DOI URL |
Abstract: Measurements of soil CO(2) efflux, litter production, and the surface litter pool biomass were made over a 1 year period in a tropical transitional forest near Sinop, Mato Grosso, Brazil with the aim of quantifying the seasonal variation in soil respiration and litter decomposition and the annual contribution of litter decomposition to soil CO(2) efflux. Average annual soil CO(2) efflux (+/- 95% confidence interval (CI)) was 7.91 +/- 1.16 g C m(-2) d(-1). Soil CO(2) efflux was highest during the November-February wet season (9.15 +/- 0.90 g C m(-2) d(-1)) and lowest during the May-September dry season (6.19 +/- 1.40 g C m(-2) d(-1)), and over 60% of the variation in seasonal soil CO(2) efflux was explained by seasonal variations in soil temperature and moisture. Mass balance estimates of mean (+/- 95% CI) decomposition rates were statistically different between the wet and dry seasons (0.66 +/- 0.08 and 1.65 +/- 0.10 g C m(-2) d(-1), respectively), and overall, decomposition of leaf litter comprised 16% of the average annual soil respiration. Leaf litter production was higher during the dry season, and mean (+/- 95% CI) leaf litter fall (5.6 +/- 1.7 Mg ha(-1)) comprised 73% of the total litter fall (7.8 +/- 2.3 Mg ha(-1)). Average (+/- 95% CI) annual litter pool biomass was estimated to be 5.5 +/- 0.3 Mg ha(-1), which was similar to the measured pool size (5.7 +/- 2.2 Mg ha(-1)). Overall, seasonal variations in environmental variables, specifically water availability (soil moisture and rainfall), had a profound influence on litter production, soil respiration, and surface litter decomposition. | |||||
BibTeX:
@article{valentini_soil_2008, author = {Valentini, Carla Maria Abido and Sanches, Luciana and de Paula, Sérgio Roberto and Vourlitis, George Louis and de Souza Nogueira, José and Pinto, Osvaldo Borges and de Almeida Lobo, Francisco}, title = {Soil respiration and aboveground litter dynamics of a tropical transitional forest in northwest Mato Grosso, Brazil}, journal = {Journal of Geophysical Research}, year = {2008}, volume = {113}, url = {://WOS:000262042300001}, doi = {https://doi.org/10.1029/2007jg000619} } |
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Valentini, C.M.A., Espinosa, M.M. and Roberto de Paulo, S. | Estimate of CO2 efflux of soil, of a transition forest in northwest of Mato Grosso state, using multiple regression | 2008 | Cerne Vol. 14(1), pp. 9-16 |
article | URL |
Abstract: Many research groups have being studying the contribution of tropical forests to the global carbon cycle, and the climatic consequences of substituting the forests for pastures. Considering that soil CO, efflux is the greater component of the carbon cycle of the biosphere, this work found an equation for estimating the soil CO2 efflux of an area of the Transition Forest, using a model of multiple regression for time series data of temperature and soil moisture. The study was carried out in the northwest of Mato Grosso, Brazil (11 degrees 24.75'S; 55 degrees 19.50'W), in a transition forest between cerrado and AmazonForest, 50 km far from Sinop county. Each month, throughout one year, it was measured soil CO2 efflux, temperature and soil moisture. The annual average of soil CO, efflux was 7.5 +/- 0.6 (mean SE) i Mol m(-2)s(-1), the annual mean soil temperature was 25,06 +/- 0.12 (mean +/- SE) degrees C. The study indicated that the humidity had high influence on soil CO2 efflux; however the results were more significant using a multiple regression model that estimated the logarithm of soil CO2 efflux, considering time, soil moisture and the interaction between time duration and the inverse of soil temperature. | |||||
BibTeX:
@article{valentini_estimate_2008, author = {Valentini, Carla Maria Abido and Espinosa, Mariano Martinez and Roberto de Paulo, Srgio}, title = {Estimate of CO2 efflux of soil, of a transition forest in northwest of Mato Grosso state, using multiple regression}, journal = {Cerne}, year = {2008}, volume = {14}, number = {1}, pages = {9--16}, url = {://WOS:000254582900002} } |
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Vale, R., Gomes, A.C.S., Santana, R.A.S. and Tóta, J... | Hydroclimatic variables associated with El Nino and La Nina events at the Curuá-Una hydroelectric reservoir, Central Amazonia. [BibTeX] |
2016 | Acta Amazonica Vol. 46, pp. p. 303-308 |
article | |
BibTeX:
@article{vale_hydroclimatic_2016, author = {Vale, Roseilson and Gomes, A. C. S. and Santana, R. A. S. and Tóta, Júlio .}, title = {Hydroclimatic variables associated with El Nino and La Nina events at the Curuá-Una hydroelectric reservoir, Central Amazonia.}, journal = {Acta Amazonica}, year = {2016}, volume = {46}, pages = {p. 303--308} } |
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Ungersbock, M., Rubel, F., Fuchs, T. and Rudolf, B. | Bias correction of global daily rain gauge measurements | 2001 | Physics and Chemistry of the Earth Part B-Hydrology Oceans and Atmosphere Vol. 26(5-6), pp. 411-414 |
article | DOI URL |
Abstract: Up to the present global precipitation climatologies based on rain gauges have been corrected for systematic measurement errors using monthly correction factors only. We present results from a statistical correction model for daily measurements. It was developed in the framework of BALTEX and adapted for the Global Precipitation Climatology Centre (GPCC) to correct global daily rain gauge data routinely transmitted via GTS. We focus on regions of the GEWEX continental scale experimets BALTEX (Europe), GAME (Asia), LBA (South-America) and GCIP (North-America). The correction model was applied to 2 years of data (1996, 1997) and compared with the correction factors of the widely used precipitation climatology of Legates (1987). In the BALTEX region our averaged daily correction factor is about equal to the monthly correction given by Legates during the summer months, while Legates estimated higher corrections for snow (up to 50 %). In the regions of GAME: and LBA the corrections given by Legates are also generally higher (50 - 100 %) than our corrections. This is opposite to the corrections calculated for GCIP rain gauges, which are not significantly different. (C) 2001 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{ungersbock_bias_2001, author = {Ungersbock, M. and Rubel, F. and Fuchs, T. and Rudolf, B.}, title = {Bias correction of global daily rain gauge measurements}, journal = {Physics and Chemistry of the Earth Part B-Hydrology Oceans and Atmosphere}, year = {2001}, volume = {26}, number = {5-6}, pages = {411--414}, url = {://WOS:000168209000008}, doi = {https://doi.org/10.1016/s1464-1909(01)00027-2} } |
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Uhl, C. and Nepstad, D. | Amazonia at the millennium | 2000 | Interciencia Vol. 25(3), pp. 159-164 |
article | URL |
Abstract: Much of what we thought was true about Amazon rainforest has turned out to be not quite so. As perceptions sharpen, the value of the Amazon ecosystem is becoming more fully appreciated, as are the consequences of converting this forest to other uses. Even though the regions's forest can spring back after many assaults, continued deforestation, fire, and forest fragmentation might eventually lead to the formation of a stable fire-prone scrub vegetation where rainforests now occur. To move toward lasting solutions to the knotty conservation and development problems that now face the Amazon region will require vision, a strong government presence, the continued growth of civic responsibility, agile NGOs, and vocal scientists. | |||||
BibTeX:
@article{uhl_amazonia_2000, author = {Uhl, C. and Nepstad, D.}, title = {Amazonia at the millennium}, journal = {Interciencia}, year = {2000}, volume = {25}, number = {3}, pages = {159--164}, url = {://WOS:000087356700006} } |
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Turner, D.P., Ritts, W.D., Cohen, W.B., Gower, S.T., Running, S.W., Zhao, M.S., Costa, M.H., Kirschbaum, A.A., Ham, J.M., Saleska, S.R. and Ahl, D.E. | Evaluation of MODIS NPP and GPP products across multiple biomes | 2006 | Remote Sensing of Environment Vol. 102(3-4), pp. 282-292 |
article | DOI URL |
Abstract: Estimates of daily gross primary production (GPP) and annual net primary production (NPP) at the 1 km spatial resolution are now produced operationally for the global terrestrial surface using imagery from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. Ecosystem-level measurements of GPP at eddy covariance flux towers and plot-level measurements of NPP over the surrounding landscape offer opportunities for validating the MODIS NPP and GPP products, but these flux measurements must be scaled over areas on the order of 25 km(2) to make effective comparisons to the MODIS products. Here, we report results for such comparisons at 9 sites varying widely in biome type and land use. The sites included arctic tundra, boreal forest, temperate hardwood forest, temperate conifer forest, tropical rain forest, tallgrass prairie, desert grassland, and cropland. The ground-based NPP and GPP surfaces were generated by application of the Biome-BGC carbon cycle process model in a spatially-distributed mode. Model inputs of land cover and leaf area index were derived from Landsat data. The MODIS NPP and GPP products showed no overall bias. They tended to be overestimates at low productivity sites - often because of artificially high values of MODIS FPAR (fraction of photosynthetically active radiation absorbed by the canopy), a critical input to the MODIS GPP algorithm. In contrast, the MODIS products tended to be underestimates in high productivity sites - often a function of relatively low values for vegetation light use efficiency in the MODIS GPP algorithm. A global network of sites where both NPP and GPP are measured and scaled over the local landscape is needed to more comprehensively validate the MODIS NPP and GPP products and to potentially calibrate the MODIS NPP/GPP algorithm parameters. (c) 2006 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{turner_evaluation_2006, author = {Turner, D. P. and Ritts, W. D. and Cohen, W. B. and Gower, S. T. and Running, S. W. and Zhao, M. S. and Costa, M. H. and Kirschbaum, A. A. and Ham, J. M. and Saleska, S. R. and Ahl, D. E.}, title = {Evaluation of MODIS NPP and GPP products across multiple biomes}, journal = {Remote Sensing of Environment}, year = {2006}, volume = {102}, number = {3-4}, pages = {282--292}, url = {://WOS:000238406000008}, doi = {https://doi.org/10.1016/j.rse.2006.02.017} } |
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Tunnicliffe, R.L., Ganesan, A.L., Parker, R.J., Boesch, H., Gedney, N., Poulter, B., Zhang, Z., Lavrič, J.V., Walter, D., Rigby, M., Henne, S., Young, D. and O'Doherty, S. | Quantifying sources of Brazil's CH4 emissions between 2010 and 2018 from satellite data [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(21), pp. 13041-13067 |
article | DOI URL |
BibTeX:
@article{tunnicliffe_quantifying_2020, author = {Tunnicliffe, R. L. and Ganesan, A. L. and Parker, R. J. and Boesch, H. and Gedney, N. and Poulter, B. and Zhang, Z. and Lavrič, J. V. and Walter, D. and Rigby, M. and Henne, S. and Young, D. and O'Doherty, S.}, title = {Quantifying sources of Brazil's CH4 emissions between 2010 and 2018 from satellite data}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {21}, pages = {13041--13067}, url = {https://acp.copernicus.org/articles/20/13041/2020/}, doi = {https://doi.org/10.5194/acp-20-13041-2020} } |
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Tumang, K., Victoria, A.V., R. L., R. and C.A., J.E. | On line pre-concentration for simultaneous determination of low molecular weight organic acids and inorganic anions in Amazonian river water samples employing chromatography with conductivity detection [BibTeX] |
2007 | Acta Amazonica Vol. 37, pp. 287-294 |
article | |
BibTeX:
@article{tumang_line_2007, author = {Tumang, Krusche, A.V., Victoria, R. L., Richey, J.E., C.A.}, title = {On line pre-concentration for simultaneous determination of low molecular weight organic acids and inorganic anions in Amazonian river water samples employing chromatography with conductivity detection}, journal = {Acta Amazonica}, year = {2007}, volume = {37}, pages = {287--294} } |
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Tuet, W.Y., Liu, F., Alves, N.d.O., Fok, S., Artaxo, P., Vasconcellos, P.C., Champion, J. and Nga Lee, NG | Chemical oxidative potential and cellular oxidative stress from open biomass burning aerosol [BibTeX] |
2019 | Environmental Science & Technology Letters Vol. 28, pp. 1-17 |
article | |
BibTeX:
@article{tuet_chemical_2019, author = {Tuet, Wing Y and Liu, Fobang and Alves, Nilmara de Oliveira and Fok, Shierly and Artaxo, Paulo and Vasconcellos, Perola C and Champion, Julie and NG, Nga Lee}, title = {Chemical oxidative potential and cellular oxidative stress from open biomass burning aerosol}, journal = {Environmental Science & Technology Letters}, year = {2019}, volume = {28}, pages = {1--17} } |
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Tucker, J.M., Brondizio, E.S. and Moran, E.F. | Rates of forest regrowth in eastern Amazonia: A comparison of Altamira and Bragantina regions, Para State, Brazil | 1998 | Interciencia Vol. 23(2), pp. 64-+ |
article | URL |
Abstract: Extensive areas of secondary vegetation cover the Amazonian landscape and are becoming a prominent feature surrounding rounding rural communities. In areas where much of the land has been deforested secondary succession plays a vital role in maintaining the cycle of shifting cultivation. This paper examines rates of for est regrowth, or secondary succession, following agro-pastoral activity, as a process which sustains communities living in the Amazon. First, we examine the differences in rates of succession, and secondly, reclassify regrowth stages according to vegetation structure. We compare the late of succession at two study sites within the Brazilian state of Para Altamira (Lover Xingu Basin) and Igarape-Acu (Bragantina Region), a nutrient-rich soil and nutrient-poor soil area respectively. Altamira displays a rate of forest regrowth that is nearly twice as fast as Bragantina. Density, height, and basal area clearly distinguish between the rates succession in the Altamira and Bragantina regions. An eight year old fallow in Altamira has over four times the tree basel area of an eight year old fallow in Bargantina and a canopy which is nearly seven meters taller. The two regions' distinct rates of forest succession discard any uniform scenario for secondary succession in Amazonia, but point to similar features characterizing the over all process. Soil fertility and land use history emerge as the critical factors regrowth in these two regions. Our research has show that age alone cannot be used to predict stages of development of secondary succession, since local and regional differences in land use history and soil fertility can cause structural differences among sites within the same age class. Physiognomic parameters provide a mole consistent way of comparing secondary vegetation across sites and regions. We introduce a cross-regional classification system Sol successional stages based primarily on structural criteria. Succession is divided into three stages, initial (SS1), intermediate (SS2), and advanced (SS3). The features which uniquely identify each successional stage include 1.) the relative contribution of saplings (individuals textless 10 cm and (3)2 cm DBH) and trees (individuals (3)10 cm DBH) to the total basal area, 2.) tree basal area, 3.) average total height, 4.) mode total height, 5.) average DBH, and 6.) the standard deviation of total height which indicates the degree of structural diversity among the plants. The relative contribution of saplings and trees to total basal area emerges as the primary indicator of each stage. From viewpoint of remote sensing and land use analysis, the difinition of structural parameters for regrowth stages is especially important, since structural features are associated with spectral data from satellite images. Regrowth stages based on structural criteria which can be identified independent of age will help facilitate the aggregation of cross-regional data sets, help to understand the pace of regrowth in relation to management strategies, and furthermore, aid the development of a basin-wide classification system of remotely sensed satellite images for secondary succession. | |||||
BibTeX:
@article{tucker_rates_1998, author = {Tucker, J. M. and Brondizio, E. S. and Moran, E. F.}, title = {Rates of forest regrowth in eastern Amazonia: A comparison of Altamira and Bragantina regions, Para State, Brazil}, journal = {Interciencia}, year = {1998}, volume = {23}, number = {2}, pages = {64--+}, url = {://WOS:000073529100002} } |
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Tucker, C.J., Steininger, M.K., Townshend, J.R.G., Killeen, T.R. and Desch, A. | Tropical deforestation in the Bolivian Amazon | 2000 | Vol. 4056Wavelet Applications Vii, pp. 2-11 |
incollection | DOI URL |
Abstract: Landsat satellite images from the mid-1980s and early 1990s were used to map tropical forest extent and deforestation in similar to 800,000 km(2) of Amazonian Bolivia. Forest cover extent, including tropical deciduous forest, totaled 472,000 km(2) while the area of natural non-forest formations totaled 298,000 km(2). The area deforested totaled 15,000 km(2) in the middle 1980s and 28,800 km(2) by the early 1990s. The rate of tropical deforestation in the textgreater1,000 mm y(-1) precipitation forest zone of Bolivia was 2,200 km(2) y(-1) from 1985-1986 to 1992-1994. We document a spatially-concentrated "deforestation zone" in Santa Cruz Department where textgreater60% of the Bolivian deforestation is occurring at an accelerating rate in areas of tropical deciduous dry forest. | |||||
BibTeX:
@incollection{szu_tropical_2000, author = {Tucker, C. J. and Steininger, M. K. and Townshend, J. R. G. and Killeen, T. R. and Desch, A.}, title = {Tropical deforestation in the Bolivian Amazon}, booktitle = {Wavelet Applications Vii}, year = {2000}, volume = {4056}, pages = {2--11}, url = {://WOS:000088256200001}, doi = {https://doi.org/10.1117/12.381717} } |
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Trumbore, S., Da Costa, E.S., Nepstad, D.C., De Camargo, P.B., Martinelli, L., Ray, D., Restom, T. and Silver, W. | Dynamics of fine root carbon in Amazonian tropical ecosystems and the contribution of roots to soil respiration | 2006 | Global Change Biology Vol. 12(2), pp. 217-229 |
article | DOI URL |
Abstract: Radiocarbon ((14)C) provides a measure of the mean age of carbon (C) in roots, or the time elapsed since the C making up root tissues was fixed from the atmosphere. Radiocarbon signatures of live and dead fine (textless 2 mm diameter) roots in two mature Amazon tropical forests are consistent with average ages of 4-11 years (ranging from textless 1 to textgreater 40 years). Measurements of (14)C in the structural tissues of roots known to have grown during 2002 demonstrate that new roots are constructed from recent (textless 2-year-old) photosynthetic products. High Delta(14)C values in live roots most likely indicate the mean lifetime of the root rather than the isotopic signature of inherited C or C taken up from the soil. Estimates of the mean residence time of C in forest fine roots (inventory divided by loss rate) are substantially shorter (1-3 years) than the age of standing fine root C stocks obtained from radiocarbon (4-11 years). By assuming positively skewed distributions for root ages, we can effectively decouple the mean age of C in live fine roots (measured using (14)C) from the rate of C flow through the live root pool, and resolve these apparently disparate estimates of root C dynamics. Explaining the (14)C values in soil pore space CO(2), in addition, requires that a portion of the decomposing roots be cycled through soil organic matter pools with decadal turnover time. | |||||
BibTeX:
@article{trumbore_dynamics_2006, author = {Trumbore, S. and Da Costa, E. S. and Nepstad, D. C. and De Camargo, P. B. and Martinelli, Liza and Ray, D. and Restom, T. and Silver, W.}, title = {Dynamics of fine root carbon in Amazonian tropical ecosystems and the contribution of roots to soil respiration}, journal = {Global Change Biology}, year = {2006}, volume = {12}, number = {2}, pages = {217--229}, url = {://WOS:000234974900007}, doi = {https://doi.org/10.1111/j.1365-2486.2005.001063.x} } |
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Trumbore, S. and Camargo, P.d. | Soil Carbon Dynamics [BibTeX] |
2009 | (Geophysical Monograph 186)Amazonia and Global Change, pp. 451-462 | incollection | |
BibTeX:
@incollection{ed_m_keller_soil_2009, author = {Trumbore, S. and Camargo, P.B. de}, title = {Soil Carbon Dynamics}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, number = {Geophysical Monograph 186}, pages = {451--462} } |
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Trujillo Lehmann, J., Cravo, M. and Atroch A.L. & Filho, F.L. | Fertilization and cover crop effects on soil nitrogen and plant nutrition in a young guarana plantation [BibTeX] |
2003 | Acta Amazonica Vol. 33, pp. 535-548 |
article | |
BibTeX:
@article{trujillo_fertilization_2003, author = {Trujillo, Lehmann, J.; Cravo, M.S.; Atroch, A.L. & Filho, F.J.N., L.C.}, title = {Fertilization and cover crop effects on soil nitrogen and plant nutrition in a young guarana plantation}, journal = {Acta Amazonica}, year = {2003}, volume = {33}, pages = {535--548} } |
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Trebs, I., Metzger, S., Meixner, F.X., Helas, G.N., Hoffer, A., Rudich, Y., Falkovich, A.H., Moura, M.A.L., da Silva, R.S., Artaxo, P., Slanina, J. and Andreae, M.O. | The NH4+-NO3--Cl--SO42--H2O aerosol system and its gas phase precursors at a pasture site in the Amazon Basin: How relevant are mineral cations and soluble organic acids? | 2005 | Journal of Geophysical Research-Atmospheres Vol. 110(D7) |
article | DOI URL |
Abstract: Real-time measurements of ammonia, nitric acid, hydrochloric acid, sulfur dioxide and the water-soluble inorganic aerosol species, ammonium, nitrate, chloride, and sulfate were performed at a pasture site in the Amazon Basin (Rondonia, Brazil). The measurements were made during the late dry season (biomass burning), the transition period, and the onset of the wet season (clean conditions) using a wet-annular denuder (WAD) in combination with a Steam-Jet Aerosol Collector (SJAC). Measurements were conducted from 12 September to 14 November 2002 within the framework of LBA-SMOCC (Large-Scale Biosphere Atmosphere Experiment in Amazonia-Smoke Aerosols, Clouds, Rainfall, and Climate: Aerosols From Biomass Burning Perturb Global and Regional Climate). Real-time data were combined with measurements of sodium, potassium, calcium, magnesium, and low-molecular weight (LMW) polar organic acids determined on 12-, 24-, and 48-hours integrated filter samples. The contribution of inorganic species to the fine particulate mass (D-p textless= 2.5 mu m) was frequently below 20% by mass, indicating the preponderance of organic matter. The measured concentration products of NH3 x HNO3 and NH3 x HCl persistently remained below the theoretical equilibrium dissociation constants of the NH3/HNO3/NH4NO3 and NH3/HCl/NH4Cl systems during daytime (RH textless 90%). The application of four thermodynamic equilibrium models (EQMs) indicates that the fine mode aerosol anions NO3-, Cl-, and SO42- were balanced predominantly by mineral cations (particularly pyrogenic K+) during daytime. At nighttime (RH textgreater 90%) fine-mode NH4NO3 and NH4Cl are predicted to be formed in the aqueous aerosol phase. Probably, Cl- was driven out of the aerosol phase largely by reaction of pyrogenic KCl with HNO3 and H2SO4. As shown by an updated version of the equilibrium simplified aerosol model (EQSAM(2)), which incorporates mineral aerosol species and lumped LMW polar organic acids, daytime aerosol NH4+ was mainly balanced by organic compounds. | |||||
BibTeX:
@article{trebs_nh4-no3--cl--so42--h2o_2005, author = {Trebs, I. and Metzger, S. and Meixner, F. X. and Helas, G. N. and Hoffer, A. and Rudich, Y. and Falkovich, A. H. and Moura, M. A. L. and da Silva, R. S. and Artaxo, P. and Slanina, J. and Andreae, M. O.}, title = {The NH4+-NO3--Cl--SO42--H2O aerosol system and its gas phase precursors at a pasture site in the Amazon Basin: How relevant are mineral cations and soluble organic acids?}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2005}, volume = {110}, number = {D7}, url = {://WOS:000228378100005}, doi = {https://doi.org/10.1029/2004jd005478} } |
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Trebs, I., Meixner, F.X., Slanina, J., Otjes, R., Jongejan, P. and Andreae, M.O. | Real-time measurements of ammonia, acidic trace gases and water-soluble inorganic aerosol species at a rural site in the Amazon Basin (vol 4, pg 967, 2004) [BibTeX] |
2005 | Atmospheric Chemistry and Physics Vol. 5, pp. 3451-3453 |
article | URL |
BibTeX:
@article{trebs_real-time_2005, author = {Trebs, I. and Meixner, F. X. and Slanina, J. and Otjes, R. and Jongejan, P. and Andreae, M. O.}, title = {Real-time measurements of ammonia, acidic trace gases and water-soluble inorganic aerosol species at a rural site in the Amazon Basin (vol 4, pg 967, 2004)}, journal = {Atmospheric Chemistry and Physics}, year = {2005}, volume = {5}, pages = {3451--3453}, url = {://WOS:000234143500001} } |
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Trebs, I., Meixner, F.X., Slanina, J., Otjes, R., Jongejan, P. and Andreae, M.O. | Real-time measurements of ammonia, acidic trace gases and water-soluble inorganic aerosol species at a rural site in the Amazon Basin | 2004 | Atmospheric Chemistry and Physics Vol. 4, pp. 967-987 |
article | URL |
Abstract: We measured the mixing ratios of ammonia (NH3), nitric acid (HNO3), nitrous acid (HONO), hydrochloric acid (HCl), sulfur dioxide (SO2) and the corresponding water-soluble inorganic aerosol species, ammonium (NH4+), nitrate (NO3-), nitrite (NO2-), chloride (Cl-) and sulfate (SO42-), and their diel and seasonal variations at a pasture site in the Amazon Basin (Rondonia, Brazil). This study was conducted within the framework of LBA-SMOCC ( Large Scale Biosphere Atmosphere Experiment in Amazonia-Smoke Aerosols, Clouds, Rainfall and Climate: Aerosols from Biomass Burning Perturb Global and Regional Climate). Sampling was performed from 12 September to 14 November 2002, extending from the dry season ( extensive biomass burning activity), through the transition period to the wet season ( background conditions). Measurements were made continuously using a wet-annular denuder ( WAD) in combination with a Steam-Jet Aerosol Collector (SJAC) followed by suitable on-line analysis. A detailed description and verification of the inlet system for simultaneous sampling of soluble gases and aerosol compounds is presented. Overall measurement uncertainties of the ambient mixing ratios usually remained below 15%. The limit of detection (LOD) was determined for each single data point measured during the field experiment. Median LOD values (3sigma-definition) were less than or equal to0.015 ppb for acidic trace gases and aerosol anions and less than or equal to0.118 ppb for NH3 and aerosol NH4+. Mixing ratios of acidic trace gases remained below 1 ppb throughout the measurement period, while NH3 levels were an order of magnitude higher. Accordingly, mixing ratios of NH4+ exceeded those of other inorganic aerosol contributors by a factor of 4 to 10. During the wet season, mixing ratios decreased by nearly a factor of 3 for all compounds compared to those observed when intensive biomass burning took place. Additionally, N-containing gas and aerosol species featured pronounced diel variations. This is attributed to strong relative humidity and temperature variations between day and night as well as to changing photochemistry and stability conditions of the planetary boundary layer. HONO exhibited a characteristic diel cycle with high mixing ratios at nighttime and was not completely depleted by photolysis during daylight hours. | |||||
BibTeX:
@article{trebs_real-time_2004, author = {Trebs, I. and Meixner, F. X. and Slanina, J. and Otjes, R. and Jongejan, P. and Andreae, M. O.}, title = {Real-time measurements of ammonia, acidic trace gases and water-soluble inorganic aerosol species at a rural site in the Amazon Basin}, journal = {Atmospheric Chemistry and Physics}, year = {2004}, volume = {4}, pages = {967--987}, url = {://WOS:000222321900003} } |
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Trebs, I., Mayol-Bracero, O., Pauliquevis, T., Kuhn, U., Sander, R., Ganzeveld, L., Meixner, F., Kesselmeier, J., Artaxo, P. and Andreae, M. | Impact of the Manaus urban plume on trace gas mixing ratios near the surface in the Amazon Basin: Implications for the NO-NO2-O3 photostationary state and peroxy radical levels [BibTeX] |
2012 | Journal of Geophysical Research Vol. 117(D05307), pp. doi:10.1029/2011JD016386 |
article | |
BibTeX:
@article{trebs_impact_2012, author = {Trebs, I. and Mayol-Bracero, O.L. and Pauliquevis, T. and Kuhn, U. and Sander, R. and Ganzeveld, L. and Meixner, F.X. and Kesselmeier, J. and Artaxo, P. and Andreae, M.O.}, title = {Impact of the Manaus urban plume on trace gas mixing ratios near the surface in the Amazon Basin: Implications for the NO-NO2-O3 photostationary state and peroxy radical levels}, journal = {Journal of Geophysical Research}, year = {2012}, volume = {117}, number = {D05307}, pages = {doi:10.1029/2011JD016386} } |
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Trebs, I., Lara, L.L., Zeri, L.M.M., Gatti, L.V., Artaxo, P., Dlugi, R., Slanina, J., Andreae, M.O. and Meixner, F.X. | Dry and wet deposition of inorganic nitrogen compounds to a tropical pasture site (Rondonia, Brazil) | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 447-469 |
article | URL |
Abstract: The input of nitrogen (N) to ecosystems has increased dramatically over the past decades. While total (wet + dry) N deposition has been extensively determined in temperate regions, only very few data sets of N wet deposition exist for tropical ecosystems, and moreover, reliable experimental information about N dry deposition in tropical environments is lacking. In this study we estimate dry and wet deposition of inorganic N for a remote pasture site in the Amazon Basin based on in-situ measurements. The measurements covered the late dry (biomass burning) season, a transition period and the onset of the wet season (clean conditions) (12 September to 14 November 2002) and were a part of the LBA-SMOCC (Large-Scale Biosphere-Atmosphere Experiment in Amazonia-Smoke, Aerosols, Clouds, Rainfall, and Climate) 2002 campaign. Ammonia (NH(3)), nitric acid (HNO(3)), nitrous acid (HONO), nitrogen dioxide (NO(2)), nitric oxide (NO), ozone (O(3)), aerosol ammonium (NH(4)(+)) and aerosol nitrate (NO(3)(-)) were measured in real-time, accompanied by simultaneous meteorological measurements. Dry deposition fluxes of NO(2) and HNO(3) are inferred using the "big leaf multiple resistance approach" and particle deposition fluxes are derived using an established empirical parameterization. Bi-directional surface-atmosphere exchange fluxes of NH(3) and HONO are estimated by applying a "canopy compensation point model". N dry and wet deposition is dominated by NH(3) and NH(4)(+), which is largely the consequence of biomass burning during the dry season. The grass surface appeared to have a strong potential for daytime NH(3) emission, owing to high canopy compensation points, which are related to high surface temperatures and to direct NH(3) emissions from cattle excreta. NO(2) also significantly accounted for N dry deposition, whereas HNO(3), HONO and N-containing aerosol species were only minor contributors. Ignoring NH3 emission from the vegetation surface, the annual net N deposition rate is estimated to be about -11 kgN ha(-1) yr(-1). If on the other hand, surface-atmosphere exchange of NH(3) is considered to be bi-directional, the annual net N budget at the pasture site is estimated to range from -2.15 to -4.25 kgN ha(-1) yr(-1). | |||||
BibTeX:
@article{trebs_dry_2006, author = {Trebs, I. and Lara, L. L. and Zeri, L. M. M. and Gatti, L. V. and Artaxo, P. and Dlugi, R. and Slanina, J. and Andreae, M. O. and Meixner, F. X.}, title = {Dry and wet deposition of inorganic nitrogen compounds to a tropical pasture site (Rondonia, Brazil)}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {447--469}, url = {://WOS:000235230200001} } |
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Trebs, I., Andreae, M.O., Elbert, W., Mayol-Bracero, O.L., Soto-Garcia, L.L., Rudich, Y., Falkovich, A.H., Maenhaut, W., Artaxo, P., Otjes, R. and Slanina, J. | Aerosol inorganic composition at a tropical site: Discrepancies between filter-based sampling and a semi-continuous method | 2008 | Aerosol Science and Technology Vol. 42(4), pp. 255-269 |
article | DOI URL |
Abstract: The concentrations of the water-soluble inorganic aerosol species, ammonium (NH4+), nitrate (NO3-), chloride (Cl-), and sulfate (SO42-), were measured from September to November 2002 at a pasture site in the Amazon Basin (Rondnia, Brazil) (LBA-SMOCC). Measurements were conducted using a semi-continuous technique (Wet-annular denuder/Steam-Jet Aerosol Collector: WAD/SJAC) and three integrating filter-based methods, namely (1) a denuder-filter pack (DFP: Teflon and impregnated Whatman filters), (2) a stacked-filter unit (SFU: polycarbonate filters), and (3) a High Volume dichotomous sampler (HiVol: quartz fiber filters). Measurements covered the late dry season (biomass burning), a transition period, and the onset of the wet season (clean conditions). Analyses of the particles collected on filters were performed using ion chromatography (IC) and Particle-Induced X-ray Emission spectrometry (PIXE). Season-dependent discrepancies were observed between the WAD/SJAC system and the filter-based samplers. During the dry season, when PM2.5 (D-p textless= 2.5 mu m) concentrations were similar to 100 mu g m(-3), aerosol NH4+ and SO42- measured by the filter-based samplers were on average two times higher than those determined by the WAD/SJAC. Concentrations of aerosol NO3- and Cl- measured with the HiVol during daytime, and with the DFP during day- and nighttime also exceeded those of the WAD/SJAC by a factor of two. In contrast, aerosol NO3- and Cl- measured with the SFU during the dry season were nearly two times lower than those measured by the WAD/SJAC. These differences declined markedly during the transition period and towards the cleaner conditions during the onset of the wet season (PM2.5 similar to 5 mu g m(-3)); when filter-based samplers measured on average 40-90% less than the WAD/SJAC. The differences were not due to consistent systematic biases of the analytical techniques, but were apparently a result of prevailing environmental conditions and different sampling procedures. For the transition period and wet season, the significance of our results is reduced by a low number of data points. We argue that the observed differences are mainly attributable to (a) positive and negative filter sampling artifacts, (b) presence of organic compounds and organosulfates on filter substrates, and (c) a SJAC sampling efficiency of less than 100%. | |||||
BibTeX:
@article{trebs_aerosol_2008, author = {Trebs, Ivonne and Andreae, Meinrat O. and Elbert, Wolfgang and Mayol-Bracero, Olga L. and Soto-Garcia, Lydia L. and Rudich, Yinon and Falkovich, Alla H. and Maenhaut, Willy and Artaxo, Paulo and Otjes, Rene and Slanina, Jacob}, title = {Aerosol inorganic composition at a tropical site: Discrepancies between filter-based sampling and a semi-continuous method}, journal = {Aerosol Science and Technology}, year = {2008}, volume = {42}, number = {4}, pages = {255--269}, url = {://WOS:000254948100003}, doi = {https://doi.org/10.1080/02786820801992899} } |
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Trancoso, R., Carneiro Filho, A., Tomasella, J., Schietti, J., Forsberg, B.R. and Miller, R.P. | Deforestation and conservation in major watersheds of the Brazilian Amazon | 2009 | Environmental Conservation Vol. 36(4), pp. 277-288 |
article | DOI URL |
Abstract: Conserving natural vegetation cover is of critical importance for maintaining the ecological integrity and hydrological properties of large river basins (more than 100 000 km(2)). Recent estimates indicate that more than 700 000 km(2) of Brazilian Amazon have already been deforested, and to reduce further losses and preserve the important natural and cultural resources in this region, large conservation areas have been created by the Brazilian government. The present study analysed land cover and land use change in the major watersheds of the Brazilian Amazon, in order to evaluate the current balance between deforestation and conservation of natural areas in the region. The results show that watersheds draining the southern part of the basin have suffered the highest deforestation rates, with the largest losses (8.3-20% of total basin area) occurring in the Madeira, Tapajos, Xingu, Araguaia and Tocantins river basins. Most large watersheds already have significant deforestation in their headwaters, which can affect hydrological functions and ecological sustainability. The greatest allocation of land for conservation was encountered in the Trombetas, Xingu and Negro watersheds, where conservation areas occupied 92.5, 56.9 and 50.6% of the total basin, respectively. While extensive areas of the Amazon biome have been deforested, on the scale of large watersheds there is a positive balance between conservation areas and deforestation, and on average the area delimited by conservation areas is more than three times larger than the deforested areas. An analysis by subwatersheds, however, indicates that certain regions have achieved more critical levels of deforestation, in some situations affecting more than 80% of the subwatersheds. | |||||
BibTeX:
@article{trancoso_deforestation_2009, author = {Trancoso, Ralph and Carneiro Filho, Arnaldo and Tomasella, Javier and Schietti, Juliana and Forsberg, Bruce Rider and Miller, Robert Pritchard}, title = {Deforestation and conservation in major watersheds of the Brazilian Amazon}, journal = {Environmental Conservation}, year = {2009}, volume = {36}, number = {4}, pages = {277--288}, url = {://WOS:000280607900003}, doi = {https://doi.org/10.1017/s0376892909990373} } |
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Townsend, A.R., Cleveland, C.C., Asner, G.P. and Bustamante, M.M.C. | Controls over foliar N : P ratios in tropical rain forests | 2007 | Ecology Vol. 88(1), pp. 107-118 |
article | DOI URL |
Abstract: Correlations between foliar nutrient concentrations and soil nutrient availability have been found in multiple ecosystems. These relationships have led to the use of foliar nutrients as an index of nutrient status and to the prediction of broadscale patterns in ecosystem processes. More recently, a growing interest in ecological stoichiometry has fueled multiple analyses of foliar nitrogen : phosphorus ( N: P) ratios within and across ecosystems. These studies have observed that N: P values are generally elevated in tropical forests when compared to higher latitude ecosystems, adding weight to a common belief that tropical forests are generally N rich and P poor. However, while these broad generalizations may have merit, their simplicity masks the enormous environmental heterogeneity that exists within the tropics; such variation includes large ranges in soil fertility and climate, as well as the highest plant species diversity of any biome. Here we present original data on foliar N and P concentrations from 150 mature canopy tree species in Costa Rica and Brazil, and combine those data with a comprehensive new literature synthesis to explore the major sources of variation in foliar N: P values within the tropics. We found no relationship between N: P ratios and either latitude or mean annual precipitation within the tropics alone. There is, however, evidence of seasonal controls; in our Costa Rica sites, foliar N: P values differed by 25% between wet and dry seasons. The N: P ratios do vary with soil P availability and/or soil order, but there is substantial overlap across coarse divisions in soil type, and perhaps the most striking feature of the data set is variation at the species level. Taken as a whole, our results imply that the dominant influence on foliar N: P ratios in the tropics is species variability and that, unlike marine systems and perhaps many other terrestrial biomes, the N: P stoichiometry of tropical forests is not well constrained. Thus any use of N: P ratios in the tropics to infer larger-scale ecosystem processes must comprehensively account for the diversity of any given site and recognize the broad range in nutrient requirements, even at the local scale. | |||||
BibTeX:
@article{townsend_controls_2007, author = {Townsend, Alan R. and Cleveland, Cory C. and Asner, Gregory P. and Bustamante, Mercedes M. C.}, title = {Controls over foliar N : P ratios in tropical rain forests}, journal = {Ecology}, year = {2007}, volume = {88}, number = {1}, pages = {107--118}, note = {Edition: 2007/05/11}, url = {://WOS:000245668300014}, doi = {https://doi.org/10.1890/0012-9658(2007)88%5B107:cofnri%5D2.0.co;2} } |
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Townsend, A.R., Asner, G.P., White, J.W.C. and Tans, P.P. | Land use effects on atmospheric C-13 imply a sizable terrestrial CO2 sink in tropical latitudes | 2002 | Geophysical Research Letters Vol. 29(10) |
article | DOI URL |
Abstract: [1] Records of atmospheric CO2 and (CO2)-C-13 can be used to distinguish terrestrial vs. oceanic exchanges of CO2 with the atmosphere. However, this approach has proven difficult in the tropics, partly due to extensive land conversion from C-3 to C-4 vegetation. We estimated the effects of such conversion on biosphere- atmosphere C-13 exchange for 1991-2000, and then explored how this "land-use disequilibrium'' altered the partitioning of net atmospheric CO2 exchanges between ocean and land using NOAA-CMDL data and a 2D, zonally averaged atmospheric transport model. Our results suggest sizable CO2 uptake in C-3-dominated tropical regions in 8 of the 10 years; 1997 and 1998, which included a strong ENSO event, are near neutral. Since these fluxes include any deforestation source, our findings imply either that such sources are smaller than previously estimated, and/or the existence of a large equatorial terrestrial CO2 sink. | |||||
BibTeX:
@article{townsend_land_2002, author = {Townsend, A. R. and Asner, G. P. and White, J. W. C. and Tans, P. P.}, title = {Land use effects on atmospheric C-13 imply a sizable terrestrial CO2 sink in tropical latitudes}, journal = {Geophysical Research Letters}, year = {2002}, volume = {29}, number = {10}, url = {://WOS:000178888300080}, doi = {https://doi.org/10.1029/2001gl013454} } |
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Townsend, A.R., Asner, G.P., Cleveland, C.C., Lefer, M.E. and Bustamante, M.M.C. | Unexpected changes in soil phosphorus dynamics along pasture chronosequences in the humid tropics | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Phosphorus (P) is widely believed to limit plant growth and organic matter storage in a large fraction of the world's lowland tropical rain forests. We investigated how the most common land use change in such forests, conversion to cattle pasture, affects soil P fractions along pasture chronosequences in the central Brazilian Amazon and in southwestern Costa Rica. Our sites represent a broad range in rainfall, soil type, management strategies, and total soil P (45.2-1228.0 mug P/g soil), yet we found some unexpected and at times quite similar changes in soil P in all sites. In the Brazilian sites, where rainfall is relatively low and pasture management is more intense than in the Costa Rican sites, significant losses in total soil P and soil organic carbon (SOC) were seen with pasture age on already P-deficient Oxisol and Entisol soils. However, P losses were from inorganic soil P fractions, while organic forms of soil P remained constant or increased with pasture age, despite the declines in SOC. In Costa Rica, SOC remained constant across the Oxisol sites and increased from forest to pasture on the Mollisols, while soil organic P increased with pasture age in both sequences. | |||||
BibTeX:
@article{townsend_unexpected_2002, author = {Townsend, A. R. and Asner, G. P. and Cleveland, C. C. and Lefer, M. E. and Bustamante, M. M. C.}, title = {Unexpected changes in soil phosphorus dynamics along pasture chronosequences in the humid tropics}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200023}, doi = {https://doi.org/10.1029/2001jd000650} } |
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Tota, J., Fitzjarrald, D.R., Staebler, R.M., Sakai, R.K., Moraes, O.M.M., Acevedo, O.C., Wofsy, S.C. and Manzi, A.O. | Amazon rain forest subcanopy flow and the carbon budget: Santarem LBA-ECO site | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: Horizontal and vertical CO(2) fluxes and gradients were made in an Amazon tropical rain forest, the Tapajos National Forest Reserve (FLONA-Tapajos: 54 degrees 580 ' W, 2 degrees 51 ' S). Two observational campaigns in 2003 and 2004 were conducted to describe subcanopy flows, clarify their relationship to winds above the forest, and estimate how they may transport CO(2) horizontally. It is now recognized that subcanopy transport of respired CO(2) is missed by budgets that rely only on single point eddy covariance measurements, with the error being most important under nocturnal calm conditions. We tested the hypothesis that horizontal mean transport, not previously measured in tropical forests, may account for the missing CO(2) in such conditions. A subcanopy network of wind and CO(2) sensors was installed. Significant horizontal transport of CO(2) was observed in the lowest 10 m of the canopy. Results indicate that CO(2) advection accounted for 73% and 71%, respectively, of the carbon budget for all calm nights evaluated during dry and wet periods. We found that horizontal advection is likely important to the canopy CO(2) budget even for conditions with the above-canopy friction velocity higher than commonly used thresholds. | |||||
BibTeX:
@article{tota_amazon_2008, author = {Tota, Julio and Fitzjarrald, David R. and Staebler, Ralf M. and Sakai, Ricardo K. and Moraes, Osvaldo M. M. and Acevedo, Otavio C. and Wofsy, Steven C. and Manzi, Antonio O.}, title = {Amazon rain forest subcanopy flow and the carbon budget: Santarem LBA-ECO site}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000257998700003 http://www.agu.org/pubs/crossref/2008/2007JG000597.shtml}, doi = {https://doi.org/10.1029/2007jg000597} } |
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Tota, J., Fitzjarrald, D. and da Silva Dias, M. | Amazon rainforest exchange of carbon and subcanopy air flow: Manaus LBA site--a complex terrain condition. | 2012 | The ScientificWorld Journal Vol. 2012, pp. 165067 |
article | DOI URL |
Abstract: On the moderately complex terrain covered by dense tropical Amazon Rainforest (Reserva Biologica do Cuieiras--ZF2--02 degrees 36'17.1'' S, 60 degrees 12'24.4'' W), subcanopy horizontal and vertical gradients of the air temperature, CO(2) concentration and wind field were measured for the dry and wet periods in 2006. We tested the hypothesis that horizontal drainage flow over this study area is significant and can affect the interpretation of the high carbon uptake rates reported by previous works at this site. A similar experimental design as the one by Tota et al. (2008) was used with a network of wind, air temperature, and CO(2) sensors above and below the forest canopy. A persistent and systematic subcanopy nighttime upslope (positive buoyancy) and daytime downslope (negative buoyancy) flow pattern on a moderately inclined slope (12%) was observed. The microcirculations observed above the canopy (38 m) over the sloping area during nighttime presents a downward motion indicating vertical convergence and correspondent horizontal divergence toward the valley area. During the daytime an inverse pattern was observed. The micro-circulations above the canopy were driven mainly by buoyancy balancing the pressure gradient forces. In the subcanopy space the microcirculations were also driven by the same physical mechanisms but probably with the stress forcing contribution. The results also indicated that the horizontal and vertical scalar gradients (e.g., CO(2)) were modulated by these micro-circulations above and below the canopy, suggesting that estimates of advection using previous experimental approaches are not appropriate due to the tridimensional nature of the vertical and horizontal transport locally. This work also indicates that carbon budget from tower-based measurement is not enough to close the system, and one needs to include horizontal and vertical advection transport of CO(2) into those estimates. | |||||
BibTeX:
@article{tota_amazon_2012, author = {Tota, J. and Fitzjarrald, D.R. and da Silva Dias, M.A.}, title = {Amazon rainforest exchange of carbon and subcanopy air flow: Manaus LBA site--a complex terrain condition.}, journal = {The ScientificWorld Journal}, year = {2012}, volume = {2012}, pages = {165067}, note = {Edition: 2012/05/24}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22619608 http://www.tswj.com/2012/165067/}, doi = {https://doi.org/10.1100/2012/165067} } |
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Tota, F., Fuentes, G., Oliveira, J., Garstang, P.J., Heitz, M., Sigler, R. and J., J. | Análise da Variabilidade Diária da precipitação em áreas de pastagem para a época Chuvosa de 1999- Projeto TRMM/LBA [BibTeX] |
2000 | Acta Amazonica Vol. 30(4), pp. 629-639 |
article | |
BibTeX:
@article{tota_alise_2000, author = {Tota, Fisch, G., Fuentes, J., Oliveira, P.J., Garstang, M., Heitz, R., Sigler, J., J.}, title = {Análise da Variabilidade Diária da precipitação em áreas de pastagem para a época Chuvosa de 1999- Projeto TRMM/LBA}, journal = {Acta Amazonica}, year = {2000}, volume = {30}, number = {4}, pages = {629--639} } |
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Torello-Raventos, T., Veenendaal, E., Schrodt, F., Saiz, G., Domingues, T., Djagbletey, G., Ford, A., Kemp, J., Marimon, B., Marimon-Junior, B., Lenza, E., Ratter, J., Maracahipes, L., Sasaki, D., Sonké, B., Zapfack, L., Taedoumg, H., Villarroel, D., Schwarz, M., Quesada, C., Ishida, F., Nardoto, G., Affum-Baffoe, K., Arroyo, L., et al. , M. and Feldpausch | On the delineation of tropical vegetation types with an emphasis on forest/ savanna transitions [BibTeX] |
2013 | Plant Ecology & Diversity Vol. 6, pp. 101-137 |
article | |
BibTeX:
@article{torello-raventos_delineation_2013, author = {Torello-Raventos, T.R.; Veenendaal, E.; Schrodt, F.; Saiz, G.; Domingues, T.F.; Djagbletey, G.; Ford, A.; Kemp, J.; Marimon, B.S.; Marimon-Junior, B.; Lenza, E.; Ratter, J.A.; Maracahipes, L.; Sasaki, D.; Sonké, B.; Zapfack, L.; Taedoumg, H.; Villarroel, D.; Schwarz, M.; Quesada, C.A.; Ishida, F.Y.; Nardoto, G.B.; Affum-Baffoe, K.; Arroyo, L.; et al., M.; Feldpausch}, title = {On the delineation of tropical vegetation types with an emphasis on forest/ savanna transitions}, journal = {Plant Ecology & Diversity}, year = {2013}, volume = {6}, pages = {101--137} } |
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Toomey, M., Roberts, D. and Nelson, B. | The influence of epiphylls on remote sensing of humid forests | 2009 | Remote Sensing of Environment Vol. 113(8), pp. 1787-1798 |
article | DOI URL |
Abstract: Epiphylls - lichens, fungi, liverworts, etc. infesting leaf surfaces - are found throughout humid forests of the world. It is well understood that epiphylls inhibit light interception by host plants, but their effect on remote sensing of colonized forests has not been examined. Incorporating leaf-level spectra from Terra Firme (primary forest) and Amazonian Caatinga (woodlands/forest growing on nutrient-deficient sandy soils), we used the GeoSAIL model to propagate leaf-level measurements to the canopy level and determine their effect on commonly used vegetation indices. In Caatinga, moderate infestations (50% leaf area epiphyll cover), lowered simulated Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) values by 6.1% and 20.4%, respectively, largely due to near infrared dampening. Heavy infestation (100% cover) simulations exhibited decreases 1.5-2 times greater than those of moderate infestations. For Terra Firme, which are generally less affected by epiphylls, moderate (20% leaf area) and heavy infestations (40%) lowered EVI by 4.4% (S.D. 0.8%) and 8.1% (S.D. 1.5%), respectively. Near infrared and green reflectance were most affected at the canopy level, showing mean decreases of 10.6% (S.D. 2.25%) and 9.5% (S.D. 3.49%), respectively, in heavy Terra Firme infestations. Time series of Moderate Resolution Imaging Spectrometer (MODIS) data corroborated the modeling results, suggesting a degree of coupling between epiphyll cover and the EVI and NDVI. These results suggest that, without explicit consideration of the presence of epiphylls, remote sensing-based methodologies may underestimate leaf area index, biomass and productivity in humid forests. (C) 2009 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{toomey_influence_2009, author = {Toomey, M. and Roberts, D. and Nelson, B.}, title = {The influence of epiphylls on remote sensing of humid forests}, journal = {Remote Sensing of Environment}, year = {2009}, volume = {113}, number = {8}, pages = {1787--1798}, url = {://000267163200019}, doi = {https://doi.org/10.1016/j.rse.2009.04.002} } |
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Tong, H., Zhang, Y., Filippi, A., Wang, T., Li, C., Liu, F., Leppla, D., Kourtchev, I., Wang, K., Keskinen, H.-M., Levula, J.T., Arangio, A.M., Shen, F., Ditas, F., Martin, S.T., Artaxo, P., Godoi, R.H.M., Yamamoto, C.I., de Souza, R.A.F., Huang, R.-J., Berkemeier, T., Wang, Y., Su, H., Cheng, Y., Pope, F.D., Fu, P., Yao, M., Pöhlker, C., Petäjä, T., Kulmala, M., Andreae, M.O., Shiraiwa, M., Pöschl, U., Hoffmann, T. and Kalberer, M. | Radical Formation by Fine Particulate Matter Associated with Highly Oxygenated Molecules [BibTeX] |
2019 | Environmental Science & Technology Vol. 53(21), pp. 12506-12518 |
article | DOI URL |
BibTeX:
@article{tong_radical_2019, author = {Tong, Haijie and Zhang, Yun and Filippi, Alexander and Wang, Ting and Li, Chenpei and Liu, Fobang and Leppla, Denis and Kourtchev, Ivan and Wang, Kai and Keskinen, Helmi-Marja and Levula, Janne T. and Arangio, Andrea M. and Shen, Fangxia and Ditas, Florian and Martin, Scot T. and Artaxo, Paulo and Godoi, Ricardo H. M. and Yamamoto, Carlos I. and de Souza, Rodrigo A. F. and Huang, Ru-Jin and Berkemeier, Thomas and Wang, Yueshe and Su, Hang and Cheng, Yafang and Pope, Francis D. and Fu, Pingqing and Yao, Maosheng and Pöhlker, Christopher and Petäjä, Tuukka and Kulmala, Markku and Andreae, Meinrat O. and Shiraiwa, Manabu and Pöschl, Ulrich and Hoffmann, Thorsten and Kalberer, Markus}, title = {Radical Formation by Fine Particulate Matter Associated with Highly Oxygenated Molecules}, journal = {Environmental Science & Technology}, year = {2019}, volume = {53}, number = {21}, pages = {12506--12518}, url = {https://doi.org/10.1021/acs.est.9b05149}, doi = {https://doi.org/10.1021/acs.est.9b05149} } |
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Tomasella, P., Borma, L., Marengo, J., Nobre, C., Bittencourt, O., Prado, M., Rodriguez, D., Cuartas L.A., J. and Pinho | The droughts of 1997 and 2005 in Amazonia: floodplain hydrology and its potential ecological and human impacts [BibTeX] |
2013 | Climatic Change Vol. 116, pp. 723-746 |
article | |
BibTeX:
@article{tomasella_droughts_2013, author = {Tomasella, P.F.; Borma, L.S.; Marengo, J.A.; Nobre, C.A.; Bittencourt, O.R.F.O.; Prado, M.C.R.; Rodriguez, D.A.; Cuartas, L.A., J.; Pinho}, title = {The droughts of 1997 and 2005 in Amazonia: floodplain hydrology and its potential ecological and human impacts}, journal = {Climatic Change}, year = {2013}, volume = {116}, pages = {723--746} } |
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Tomasella, J., Neill, C., Figueiredo, R. and Nobre, A. | Water and Chemical Budgets at the Catchment Scale Including Nutrient Exports From Intact Forests and Disturbed Landscapes [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 505-524 |
incollection | |
BibTeX:
@incollection{m_keller_water_2009, author = {Tomasella, J. and Neill, C. and Figueiredo, R. and Nobre, A.D.}, title = {Water and Chemical Budgets at the Catchment Scale Including Nutrient Exports From Intact Forests and Disturbed Landscapes}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {505--524} } |
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Tomasella, J., Hodnett, M.G., Cuartas, L.A., Nobre, A.D., Waterloo, M.J. and Oliveira, S.M. | The water balance of an Amazonian micro-catchment: the effect of interannual variability of rainfall on hydrological behaviour | 2007 | Hydrological Processes Vol. 22(13), pp. 2133-2147 |
article | DOI URL |
Abstract: In humid tropical systems, the large intraseasonal and interannual variability of rainfall can significantly affect all components of the water balance. This variability and the lack of detailed hydrological and meteorological data in both temporal and spatial scales have created uncertainties regarding the closure of the water balance for the Amazon basin. Previous studies in Amazonian micro-catchments suggested that both the unsaturated and groundwater system, which are not taken into consideration in basin-wide water budgets published in the literature, play an important role in controlling the timing of runoff generation. In this paper, the components of the water balance and the variations in different storages within the system were examined using 3 years' data from a 6.58 km(2) micro-catchment in central Amazonia. The role and relative importance of the various stores were examined. The results show a strong memory effect in the groundwater system that carries over seasonal climate anomalies from one year to the next and affects the hydrological response well beyond the time span of the anomaly. In addition, the deep unsaturated zone was found to play a key role in reducing most of the intraseasonal variability and also affected the groundwater recharge. This memory effect is crucial for sustaining streamflow and evaporation in years with rainfall deficiency. The memory effect caused by storage in the groundwater and unsaturated systems may also prevent the closure of annual large-scale water balances, which assume that storage returns to a standard state each year. Copyright (C) 2007 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{tomasella_water_2007, author = {Tomasella, Javier and Hodnett, Martin G. and Cuartas, Luz Adriana and Nobre, Antonio D. and Waterloo, Maarten J. and Oliveira, Sylvia M.}, title = {The water balance of an Amazonian micro-catchment: the effect of interannual variability of rainfall on hydrological behaviour}, journal = {Hydrological Processes}, year = {2007}, volume = {22}, number = {13}, pages = {2133--2147}, url = {://WOS:000257090200008}, doi = {https://doi.org/10.1002/hyp.6813} } |
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Tomasella, J., Borma, L.S., Marengo, J.A., Rodriguez, D.A., Cuartas, L.A., Nobre, C.A. and Prado, M.C.R. | The droughts of 1996-1997 and 2004-2005 in Amazonia: hydrological response in the river main-stem | 2010 | Hydrological Processes Vol. 25(8), pp. 1228-1242 |
article | DOI URL |
Abstract: Severe hydrological droughts in the Amazon have generally been associated with strong El Nino events. More than 100 years of stage record at Manaus harbour confirms that minimum water levels generally coincide with intense warming in the tropical Pacific sea waters. During 2005, however, the Amazon experienced a severe drought which was not associated with an El Nino event. Unless what usually occurs during strong El Nino events, when negative rainfall anomalies usually affect central and eastern Amazon drainage basin; rainfall deficiencies in the drought of 2005 were spatially constrained to the west and southwest of the basin. In spite of this, discharge stations at the main-stem recorded minimum water levels as low as those observed during the basin-wide 1996-1997 El Nino-related drought. The analysis of river discharges along the main-stem and major tributaries during the drought of 2004-2005 revealed that the recession on major tributaries began almost simultaneously. This was not the case in the 1996-1997 drought, when above-normal contribution of some tributaries for a short period during high water was crucial to partially counterbalance high discharge deficits of the other tributaries. Since time-lagged contributions of major tributaries are fundamental to damp the extremes in the main-stem, an almost coincident recession in almost all tributaries caused a rapid decrease in water discharges during the 2005 event. Copyright. (C) 2010 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{tomasella_droughts_2010, author = {Tomasella, Javier and Borma, Laura S. and Marengo, Jose A. and Rodriguez, Daniel A. and Cuartas, Luz A. and Nobre, Carlos A. and Prado, Maria C. R.}, title = {The droughts of 1996-1997 and 2004-2005 in Amazonia: hydrological response in the river main-stem}, journal = {Hydrological Processes}, year = {2010}, volume = {25}, number = {8}, pages = {1228--1242}, url = {://WOS:000289425700003}, doi = {https://doi.org/10.1002/hyp.7889} } |
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Tokay, A., Kruger, A., Krajewski, W.F., Kucera, P.A. and Pereira, A.J. | Measurements of drop size distribution in the southwestern Amazon basin | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Simultaneous observations of an optical and an impact type disdrometer and their application in radar rainfall estimation are evaluated. The disdrometers and two collocated rain gauges were operated in the southwest Amazon region of Brazil in 1999 as part of a NASA Tropical Rainfall Measuring Mission (TRMM) field campaign and the hydro-meteorological component of the Large Scale Biosphere-Atmosphere Experiment (LBA). During the experiment, we observed large drops with diameters greater than 5 mm. These large drops were not adequately detected by the impact disdrometer and resulted in differences in drop size distribution and integral rain parameters derived from the two sensors. Considering coincident observations, we calculated that the impact disdrometer recorded about 11% lower rainfall accumulations than the optical disdrometer. In addition, radar rainfall algorithms, which we derived from the impact and optical disdrometer measurements, showed instrument dependency. Out of four radar rainfall algorithms that we considered, rain rate derived from specific differential phase has the least dependency, while the rain rate derived from reflectivity at horizontal polarization and differential reflectivity combined exhibited the largest. We also observed the characteristics of rainfall and drop size distribution in two distinct wind regimes present during the TRMM-LBA field campaign. Rain was heavier in the easterly regime, with more large drops being present. | |||||
BibTeX:
@article{tokay_measurements_2002, author = {Tokay, A. and Kruger, A. and Krajewski, W. F. and Kucera, P. A. and Pereira, A. J.}, title = {Measurements of drop size distribution in the southwestern Amazon basin}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200009}, doi = {https://doi.org/10.1029/2001jd000355} } |
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Tipper, R., Malhi, Y., Meir, P., Glace, J. and Jarvis, P. | Woods and sinks [BibTeX] |
1999 | New Scientist Vol. 164(2212), pp. 59-59 |
article | URL |
BibTeX:
@article{tipper_woods_1999, author = {Tipper, R. and Malhi, Y. and Meir, P. and Glace, J. and Jarvis, P.}, title = {Woods and sinks}, journal = {New Scientist}, year = {1999}, volume = {164}, number = {2212}, pages = {59--59}, url = {://WOS:000083708900038} } |
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Tian, H.Q., Melillo, J.M., Kicklighter, D.W., McGuire, A.D., Helfrich, J.V.K., Moore, B. and Vorosmarty, C.J. | Effect of interannual climate variability on carbon storage in Amazonian ecosystems | 1998 | Nature Vol. 396(6712), pp. 664-667 |
article | DOI URL |
Abstract: The Amazon Basin contains almost one-half of the world's undisturbed tropical evergreen forest as well as large areas of tropical savanna(1,2). The forests account for about 10 per cent of the world's terrestrial primary productivity and for a similar fraction of the carbon stored in land ecosystems(2,3), and short-term held measurements' suggest that these ecosystems are globally important carbon sinks. But tropical land ecosystems have experienced substantial interannual climate variability owing to frequent El Nino episodes in recent decades(5). Of particular importance to climate change policy is how such climate variations, coupled with increases in atmospheric CO2 concentration, affect terrestrial carbon storage(6-8). Previous model analyses have demonstrated the importance of temperature in controlling carbon storage(9,10). Here we use a transient process-based biogeochemical model of terrestrial ecosystems(3,11) to investigate interannual variations of carbon storage in undisturbed Amazonian ecosystems in response to climate variability and increasing atmospheric CO2 concentration during the period 1980 to 1994. In El Nino years, which bring hot, dry weather to much of the Amazon region, the ecosystems act as a source of carbon to the atmosphere (up to 0.2 petagrams of carbon in 1987 and 1992). In other years, these ecosystems act as a carbon sink (up to 0.7 Pg C in 1981 and 1993). These fluxes are large; they compare to a 0.3 Pg C per year source to the atmosphere associated with deforestation in the Amazon Basin in the early 1990s(12). Soil moisture, which is affected by both precipitation and temperature, and which affects both plant and soil processes, appears to be an important central on carbon storage. | |||||
BibTeX:
@article{tian_effect_1998, author = {Tian, H. Q. and Melillo, J. M. and Kicklighter, D. W. and McGuire, A. D. and Helfrich, J. V. K. and Moore, B. and Vorosmarty, C. J.}, title = {Effect of interannual climate variability on carbon storage in Amazonian ecosystems}, journal = {Nature}, year = {1998}, volume = {396}, number = {6712}, pages = {664--667}, url = {://WOS:000077694200050}, doi = {https://doi.org/10.1038/25328} } |
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Tian, H., Melillo, J.M., Kicklighter, D.W., McGuire, A.D., Helfrich, J., Moore, B. and Vorosmarty, C.J. | Climatic and biotic controls on annual carbon storage in Amazonian ecosystems | 2000 | Global Ecology and Biogeography Vol. 9(4), pp. 315-335 |
article | DOI URL |
Abstract: 1 The role of undisturbed tropical land ecosystems in the global carbon budget is not well understood. It has been suggested that interannual climate variability can affect the capacity of these ecosystems to store carbon in the short term. In this paper, we use a transient version of the Terrestrial Ecosystem Model (TEM) to estimate annual carbon storage in undisturbed Amazonian ecosystems during the period 1980-94, and to understand the underlying causes of the year-to-year variations in net carbon storage for this region. 2 We estimate that the total carbon storage in the undisturbed ecosystems of the Amazon Basin in 1980 was 127.6 Pg C, with about 94.3 Pg C in vegetation and 33.3 Pg C in the reactive pool of soil organic carbon. About 83% of the total carbon storage occurred in tropical evergreen forests. Based on our model's results, we estimate that, over the past 15 years, the total carbon storage has increased by 3.1 Pg C (+ 2%), with a 1.9-Pg C (+2%) increase in vegetation carbon and a 1.2-Pg C (+4%) increase in reactive soil organic carbon. The modelled results indicate that the largest relative changes in net carbon storage have occurred in tropical deciduous forests, but that the largest absolute changes in net carbon storage have occurred in the moist and wet forests of the Basin. 3 Our results show that the strength of interannual variations in net carbon storage of undisturbed ecosystems in the Amazon Basin varies from a carbon source of 0.2 Pg C/year to a carbon sink of 0.7 Pg C/year. Precipitation, especially the amount received during the drier months, appears to be a major controller of annual net carbon storage in the Amazon Basin. Our analysis indicates further that changes in precipitation combine with changes in temperature to affect net carbon storage through influencing soil moisture and nutrient availability. 4 On average, our results suggest that the undisturbed Amazonian ecosystems accumulated 0.2 Pg C/year as a result of climate variability and increasing atmospheric CO2 over the study period. This amount is large enough to have compensated for most of the carbon losses associated with tropical deforestation in the Amazon during the same period. 5 Comparisons with empirical data indicate that climate variability and CO2 fertilization explain most of the variation in net carbon storage for the undisturbed ecosystems. Our analyses suggest that assessment of the regional carbon budget in the tropics should be made over at least one cycle of El Nino-Southern Oscillation because of interannual climate variability. Our analyses also suggest that proper scaling of the site-specific and subannual measurements of carbon fluxes to produce Basin-wide flux estimates must take into account seasonal and spatial variations in net carbon storage. | |||||
BibTeX:
@article{tian_climatic_2000, author = {Tian, H. and Melillo, J. M. and Kicklighter, D. W. and McGuire, A. D. and Helfrich, J. and Moore, B. and Vorosmarty, C. J.}, title = {Climatic and biotic controls on annual carbon storage in Amazonian ecosystems}, journal = {Global Ecology and Biogeography}, year = {2000}, volume = {9}, number = {4}, pages = {315--335}, url = {://WOS:000089055400005 http://onlinelibrary.wiley.com/store/10.1046/j.1365-2699.2000.00198.x/asset/j.1365-2699.2000.00198.x.pdf?v=1&t=h6hwwe7i&s=5b72d0ecdbf2cba8ea1aee7c881cc675ef3858d8}, doi = {https://doi.org/10.1046/j.1365-2699.2000.00198.x} } |
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Thomas, S.M., Neill, C., Deegan, L.A., Krusche, A.V., Ballester, V.M. and Victoria, R.L. | Influences of land use and stream size on particulate and dissolved materials in a small Amazonian stream network | 2004 | Biogeochemistry Vol. 68(2), pp. 135-151 |
article | DOI URL |
Abstract: We investigated the influences of forest or pasture land use and stream size on particulate and dissolved material concentrations in a network of second to third order streams in Rondonia, in the Brazilian Amazon. During the dry season, a second order stream originating in pasture had lower concentrations of dissolved oxygen and nitrate, higher concentrations of chlorophyll, total suspended solids, particulate organic carbon, particular organic nitrogen, ammonium, and phosphate than a second order stream originating in forest. Where the second order forest stream exited forest and entered pasture, concentrations of dissolved oxygen dropped from 6 mg/L to almost 0 mg/L and nitrate concentrations dropped from 12 muM to 2 muM over a reach of 2 km. These changes indicated a strong influence of land use. During the rainy season, differences among reaches of all particulate and dissolved materials were diminished. Concentrations of oxygen, chlorophyll, total suspended solids, particulate organic carbon and nitrogen, nitrate, ammonium, and phosphate in the third order pasture stream more closely resembled the second order forest stream than the second order pasture stream, suggesting that conditions in the channels of larger pasture streams more strongly control concentrations of these materials. If this pattern is widespread in stream networks of regions that consist of a mosaic of forest and pasture lands, it may have important consequences for understanding the effects of deforestation on larger rivers of the Amazon Basin. This would indicate that the effects of forest clearing on the concentrations of many suspended and dissolved materials will be most easily detected in very small streams but potentially difficult to detect in larger streams and rivers. | |||||
BibTeX:
@article{thomas_influences_2004, author = {Thomas, S. M. and Neill, C. and Deegan, L. A. and Krusche, A. V. and Ballester, V. M. and Victoria, R. L.}, title = {Influences of land use and stream size on particulate and dissolved materials in a small Amazonian stream network}, journal = {Biogeochemistry}, year = {2004}, volume = {68}, number = {2}, pages = {135--151}, url = {://WOS:000221102500001}, doi = {https://doi.org/10.1023/B:BIOG.0000025734.66083.b7} } |
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Thalman, de Sá, S. S., Palm, B. B., Barbosa, H. M. J., Pöhlker, M. L., Alexander, M. L., Brito, J., Carbone, S., Castillo, P., Day, D. A., Kuang, C., Manzi, A., Ng, N. L., Sedlacek III, A. J., Souza, R., Springston, S., Watson, T., Pöhlker, C., Pöschl, U., Andreae, M. O., Artaxo, P., Jimenez, J. L., Martin, S. T., and Wang, J., R. | CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions [BibTeX] |
2017 | Atmos. Chem. Phys. Vol. 17, pp. 11779-11801 |
article | DOI |
BibTeX:
@article{thalman_ccn_2017, author = {Thalman, de Sá, S. S., Palm, B. B., Barbosa, H. M. J., Pöhlker, M. L., Alexander, M. L., Brito, J., Carbone, S., Castillo, P., Day, D. A., Kuang, C., Manzi, A., Ng, N. L., Sedlacek III, A. J., Souza, R., Springston, S., Watson, T., Pöhlker, C., Pöschl, U., Andreae, M. O., Artaxo, P., Jimenez, J. L., Martin, S. T., and Wang, J., R.}, title = {CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions}, journal = {Atmos. Chem. Phys.}, year = {2017}, volume = {17}, pages = {11779--11801}, doi = {https://doi.org/10.5194/acp-17-11779-2017} } |
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Ter Steege, N. C. A. Killeen, T. J. Laurance, W. F. Peres, C. A. Guevara, J. E. Salomao, R. P. Castilho, C. V. Amaral, I. L. de Almeida Matos, F. D. de Souza Coelho, L. Magnusson, W. E. Phillips, O. L. DE Andrade Lima Filho, D. de Jesus Veiga Carim, M., H. Pitman and Irume, M. P. Molino, J.-F. Sabatier, D. Wittmann, F. Lopez, D. C. da Silva Guimaraes, J. R. Mendoza, A. M. Vargas, P. N. Manzatto, A. G., et al., M. V. Martins | Estimating the global conservation status of more than 15,000 Amazonian tree species [BibTeX] |
2015 | Science Advances Vol. 1, pp. e1500936- e1500936 |
article | |
BibTeX:
@article{ter_steege_estimating_2015, author = {Ter Steege, N. C. A. Killeen, T. J. Laurance, W. F. Peres, C. A. Guevara, J. E. Salomao, R. P. Castilho, C. V. Amaral, I. L. de Almeida Matos, F. D. de Souza Coelho, L. Magnusson, W. E. Phillips, O. L. DE Andrade Lima Filho, D. de Jesus Veiga Carim, M., H. Pitman and Irume, M. P. Molino, J.-F. Sabatier, D. Wittmann, F. Lopez, D. C. da Silva Guimaraes, J. R. Mendoza, A. M. Vargas, P. N. Manzatto, A. G., et al., M. V. Martins}, title = {Estimating the global conservation status of more than 15,000 Amazonian tree species}, journal = {Science Advances}, year = {2015}, volume = {1}, pages = {e1500936-- e1500936} } |
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Ter Steege, H., Pitman, N.C.A., Phillips, O.L., Chave, J., Sabatier, D., Duque, A., Molino, J.-F., Prevost, M.-F., Spichiger, R., Castellanos, H., von Hildebrand, P. and Vasquez, R. | Continental-scale patterns of canopy tree composition and function across Amazonia | 2006 | Nature Vol. 443(7110), pp. 444-447 |
article | DOI URL |
Abstract: The world's greatest terrestrial stores of biodiversity and carbon are found in the forests of northern South America, where large-scale biogeographic patterns and processes have recently begun to be described(1-4). Seven of the nine countries with territory in the Amazon basin and the Guiana shield have carried out large-scale forest inventories, but such massive data sets have been little exploited by tropical plant ecologists(5-8). Although forest inventories often lack the species-level identifications favoured by tropical plant ecologists, their consistency of measurement and vast spatial coverage make them ideally suited for numerical analyses at large scales, and a valuable resource to describe the still poorly understood spatial variation of biomass, diversity, community composition and forest functioning across the South American tropics(9). Here we show, by using the seven forest inventories complemented with trait and inventory data collected elsewhere, two dominant gradients in tree composition and function across the Amazon, one paralleling a major gradient in soil fertility and the other paralleling a gradient in dry season length. The data set also indicates that the dominance of Fabaceae in the Guiana shield is not necessarily the result of root adaptations to poor soils ( nodulation or ectomycorrhizal associations) but perhaps also the result of their remarkably high seed mass there as a potential adaptation to low rates of disturbance. | |||||
BibTeX:
@article{ter_steege_continental-scale_2006, author = {Ter Steege, Hans and Pitman, Nigel C. A. and Phillips, Oliver L. and Chave, Jerome and Sabatier, Daniel and Duque, Alvaro and Molino, Jean-Francois and Prevost, Marie-Francois and Spichiger, Rodolphe and Castellanos, Hernan and von Hildebrand, Patricio and Vasquez, Rodolfo}, title = {Continental-scale patterns of canopy tree composition and function across Amazonia}, journal = {Nature}, year = {2006}, volume = {443}, number = {7110}, pages = {444--447}, note = {Edition: 2006/09/29}, url = {://WOS:000240798800043}, doi = {https://doi.org/10.1038/nature05134} } |
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Ter Steege, H., Pitman, N., Sabatier, D., Castellanos, H., Van der Hout, P., Daly, D.C., Silveira, M., Phillips, O., Vasquez, R., Van Andel, T., Duivenvoorden, J., De Oliveira, A.A., Ek, R., Lilwah, R., Thomas, R., Van Essen, J., Baider, C., Maas, P., Mori, S., Terborgh, J., Vargas, P.N., Mogollon, H. and Morawetz, W. | A spatial model of tree alpha-diversity and tree density for the Amazon | 2003 | Biodiversity and Conservation Vol. 12(11), pp. 2255-2277 |
article | DOI URL |
Abstract: Large-scale patterns of Amazonian biodiversity have until now been obscured by a sparse and scattered inventory record. Here we present the first comprehensive spatial model of tree alpha-diversity and tree density in Amazonian rainforests, based on the largest-yet compilation of forest inventories and bolstered by a spatial interpolation technique that allows us to estimate diversity and density in areas that have never been inventoried. These data were then compared to continent-wide patterns of rainfall seasonality. We find that dry season length, while only weakly correlated with average tree alpha-diversity, is a strong predictor of tree density and of maximum tree alpha-diversity. The most diverse forests for any given DSL are concentrated in a narrow latitudinal band just south of the equator, while the least diverse forests for any given DSL are found in the Guayana Shield and Amazonian Bolivia. Denser forests are more diverse than sparser forests, even when we used a measure of diversity that corrects for sample size. We propose that rainfall seasonality regulates tree alpha-diversity and tree density by affecting shade tolerance and subsequently the number of different functional types of trees that can persist in an area. | |||||
BibTeX:
@article{ter_steege_spatial_2003, author = {Ter Steege, H. and Pitman, N. and Sabatier, D. and Castellanos, H. and Van der Hout, P. and Daly, D. C. and Silveira, M. and Phillips, O. and Vasquez, R. and Van Andel, T. and Duivenvoorden, J. and De Oliveira, A. A. and Ek, R. and Lilwah, R. and Thomas, R. and Van Essen, J. and Baider, C. and Maas, P. and Mori, S. and Terborgh, J. and Vargas, P. N. and Mogollon, H. and Morawetz, W.}, title = {A spatial model of tree alpha-diversity and tree density for the Amazon}, journal = {Biodiversity and Conservation}, year = {2003}, volume = {12}, number = {11}, pages = {2255--2277}, url = {://WOS:000183903600007}, doi = {https://doi.org/10.1023/a:1024593414624} } |
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Telles, E.D.C., de Camargo, P.B., Martinelli, L.A., Trumbore, S.E., da Costa, E.S., Santos, J., Higuchi, N. and Oliveira, R.C. | Influence of soil texture on carbon dynamics and storage potential in tropical forest soils of Amazonia (vol 17, pg 1040, 2003) [BibTeX] |
2004 | Global Biogeochemical Cycles Vol. 18(1) |
article | DOI URL |
BibTeX:
@article{telles_influence_2004, author = {Telles, E. D. C. and de Camargo, P. B. and Martinelli, L. A. and Trumbore, S. E. and da Costa, E. S. and Santos, J. and Higuchi, N. and Oliveira, R. C.}, title = {Influence of soil texture on carbon dynamics and storage potential in tropical forest soils of Amazonia (vol 17, pg 1040, 2003)}, journal = {Global Biogeochemical Cycles}, year = {2004}, volume = {18}, number = {1}, url = {://WOS:000188866800001}, doi = {https://doi.org/10.1029/2003gb002186} } |
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Telles, E.D.C., de Camargo, P.B., Martinelli, L.A., Trumbore, S.E., da Costa, E.S., Santos, J., Higuchi, N. and Oliveira, R.C. | Influence of soil texture on carbon dynamics and storage potential in tropical forest soils of Amazonia | 2003 | Global Biogeochemical Cycles Vol. 17(2) |
article | DOI URL |
Abstract: [1] Stable and radiocarbon isotopes were used to investigate the role of soil clay content in the storage and dynamics of soil carbon in tropical forest soils. Organic matter in clay-rich Oxisols and Ultisols contains at least two distinct components: ( 1) material with light delta(13)C signatures and turnover times of decades or less; and ( 2) clay-associated, C-13-enriched, carbon with turnover times of decades at the surface to millennia at depths textgreater 20 cm. Soil texture, in this case clay content, exerts a major control on the amount of slowly cycling carbon and therefore influences the storage and dynamics of carbon in tropical forest soils. Soils in primary tropical forest have been proposed as a potentially large sink for anthropogenic carbon. Comparison of carbon stocks in Oxisols sampled near Manaus, Brazil, shows no measurable change in organic carbon stocks over the past 20 years. Simple models estimating the response of soil carbon pools to a sustained 0.5% yr(-1) increase in productivity result in C storage rates of 0.09 to 0.13 MgC ha(-1) yr(-1) in soil organic matter, with additional potential storage of 0.18 to 0.27 MgC ha(-1) yr(-1) in surface litter and roots. Most storage occurs in organic matter pools with turnover times less than a decade. Export of carbon in dissolved form from upland terra firme Oxisols likely accounts for textless 0.2 MgC ha(-1) yr(-1), but more work is required to assess the export potential for periodically inundated Spodosols. | |||||
BibTeX:
@article{telles_influence_2003, author = {Telles, E. D. C. and de Camargo, P. B. and Martinelli, L. A. and Trumbore, S. E. and da Costa, E. S. and Santos, J. and Higuchi, N. and Oliveira, R. C.}, title = {Influence of soil texture on carbon dynamics and storage potential in tropical forest soils of Amazonia}, journal = {Global Biogeochemical Cycles}, year = {2003}, volume = {17}, number = {2}, url = {://WOS:000182860300002}, doi = {https://doi.org/10.1029/2002gb001953} } |
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Tejada, G., Görgens, E.B., Espírito-Santo, F.D.B., Cantinho, R.Z. and Ometto, J.P. | Evaluating spatial coverage of data on the aboveground biomass in undisturbed forests in the Brazilian Amazon [BibTeX] |
2019 | Carbon Balance and Management Vol. 14:11 |
article | |
BibTeX:
@article{tejada_evaluating_2019, author = {Tejada, G. and Görgens, E. B. and Espírito-Santo, F. D. B. and Cantinho, R. Z. and Ometto, J. P.}, title = {Evaluating spatial coverage of data on the aboveground biomass in undisturbed forests in the Brazilian Amazon}, journal = {Carbon Balance and Management}, year = {2019}, volume = {14:11} } |
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Targhetta, N., Kesselmeier, J. and Wittmann, F. | Effects of the hydroedaphic gradient on tree species composition and aboveground wood biomass of oligotrophic forest ecosystems in the central Amazon basin [BibTeX] |
2015 | Folia Geobotanica Vol. 50, pp. 185-205 |
article | |
BibTeX:
@article{targhetta_effects_2015, author = {Targhetta, N. and Kesselmeier, J. and Wittmann, F.}, title = {Effects of the hydroedaphic gradient on tree species composition and aboveground wood biomass of oligotrophic forest ecosystems in the central Amazon basin}, journal = {Folia Geobotanica}, year = {2015}, volume = {50}, pages = {185--205} } |
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Tarasova, T.A., Nobre, C.A., Holben, B.N., Eck, T.F. and Setzer, A. | Assessment of smoke aerosol impact on surface solar irradiance measured in the Rondonia region of Brazil during Smoke, Clouds, and Radiation - Brazil | 1999 | Journal of Geophysical Research-Atmospheres Vol. 104(D16), pp. 19161-19170 |
article | DOI URL |
Abstract: The impact of smoke aerosols on the surface solar irradiance in the Rondonia region of Brazil is examined. The climate of this region is subequatorial with two distinct seasons; There is a sharp decline of the precipitation and cloudiness during the dry season which lasts from June to September accompanied by anthropogenic burning of savanna and forest in August and September with the resultant strong emission of smoke into the troposphere. Thus the magnitude of the column aerosol optical depth increases in these months while both precipitable water and cloud amount decrease in accordance with the seasonal cycle of humidity. All these atmospheric constituents influence the magnitude of the solar irradiance at the surface. In order to assess the aerosol and gaseous effects on the surface irradiance as compared with impact of cloudiness, we performed the clear-sky radiative transfer model calculations by employing a broadband radiation code and both aerosol optical depth and precipitable water retrieved from Sun photometer measurements. Calculation results show that the elevated aerosol optical depth observed in Rondonia during August and September causes a negative trend in the daily mean clear-sky surface solar irradiance during this period. Since the daily mean solar irradiance measured at the surface under all-sky conditions demonstrates a similar negative trend, it can be explained by the aerosol influence while the effect of clouds appears in the daily variations of the irradiance. It was also shown that smoke aerosols cause a decrease of the monthly mean values of all-sky surface irradiance in August and September as compared with July and October. Corresponding decreases in the near surface air temperature due to the smoke aerosols were not found. | |||||
BibTeX:
@article{tarasova_assessment_1999, author = {Tarasova, T. A. and Nobre, C. A. and Holben, B. N. and Eck, T. F. and Setzer, A.}, title = {Assessment of smoke aerosol impact on surface solar irradiance measured in the Rondonia region of Brazil during Smoke, Clouds, and Radiation - Brazil}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1999}, volume = {104}, number = {D16}, pages = {19161--19170}, url = {://WOS:000082235300011 http://www.agu.org/journals/jd/v104/iD16/1999JD900258/1999JD900258.pdf}, doi = {https://doi.org/10.1029/1999jd900258} } |
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Tarasova, T.A., Nobre, C.A., Eck, T.F. and Holben, B.N. | Modeling of gaseous, aerosol, and cloudiness effects on surface solar irradiance measured in Brazil's Amazonia 1992-1995 | 2000 | Journal of Geophysical Research-Atmospheres Vol. 105(D22), pp. 26961-26969 |
article | DOI URL |
Abstract: The effects of water vapor, aerosol, and cloudiness on the incident surface solar irradiance continuously measured in Brazil's Amazonia at six observational sites from 1992 to 1995 are examined by means of a clear-sky broadband radiative transfer model. The aerosol optical depth and precipitable water, both retrieved from Sun photometer measurements, serve as inputs to the model. Computed monthly mean values of clear-sky surface irradiance are analyzed in conjunction with the monthly mean values of all-sky surface irradiance measured on the ground. To assess the effect of cloudiness, we present the cloud radiative forcing and cloud radiative forcing ratio at the surface, both widely employed in cloud radiation budget studies, By its definition the monthly mean cloud radiative forcing (cloud radiative forcing; ratio) is the difference (ratio) between surface solar irradiances under all-sky an clear-sky conditions. The analysis of the irradiances, as computed and as measured, shows that during the wet season the gaseous and cloudiness effects on the! solar radiation attenuation in the atmosphere are comparable, while the aerosol influence is much smaller. The aerosol effect increases and cloudiness effect decreases in the second half of the dry season. Thus during the biomass burning period ill southern Amazonia, the water vapor and aerosol effects become comparable, while the cloudiness impact is 2-3 times smaller. Both cloudiness and aerosol effects have strong seasonal variations, while the gaseous effect changes slightly throughout the year. | |||||
BibTeX:
@article{tarasova_modeling_2000, author = {Tarasova, T. A. and Nobre, C. A. and Eck, T. F. and Holben, B. N.}, title = {Modeling of gaseous, aerosol, and cloudiness effects on surface solar irradiance measured in Brazil's Amazonia 1992-1995}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2000}, volume = {105}, number = {D22}, pages = {26961--26969}, url = {://WOS:000165589200012}, doi = {https://doi.org/10.1029/2000jd900433} } |
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Tarasova, T.A. and Nobre, C.A. | On the temperature aerosol effect measured in Brazil's Amazonia during the dry season in smoke aerosol conditions | 2001 | Irs 2000: Current Problems in Atmospheric Radiation, pp. 737-740 | incollection | URL |
Abstract: The data of the daily minimum and maximum near surface air temperatures obtained at the observational site Reserva Jaru in Brazil's Amazonia in August-September 1995 are analyzed in conjunction with the data of the incident solar irradiance and net thermal irradiance at the surface. The solar irradiance incoming at the surface decreases from the beginning of August to mid-September in accordance with the increase of the aerosol optical depth at the mid-visible wavelength from 0.3 to 1-3. The aerosol optical depth elevation is related to the emission of smoke by the biomass burning. But the calculations show that the daily average net (downward minus upward) solar radiative flux at the top of the aerosol layer, 2 km, does not change with the aerosol optical depth elevation because both downward and upward fluxes increase simultaneously. Thus the absence of the trend in the daily maximum temperature from the beginning of August to mid-September is explained by the constant absorption of the solar radiation in both aerosol and surface layers while the positive trend in the daily minimum temperature can be explained by increasing in the night of the downward longwave radiative flux from the heated aerosol layer to the surface. | |||||
BibTeX:
@incollection{smith_temperature_2001, author = {Tarasova, T. A. and Nobre, C. A.}, title = {On the temperature aerosol effect measured in Brazil's Amazonia during the dry season in smoke aerosol conditions}, booktitle = {Irs 2000: Current Problems in Atmospheric Radiation}, year = {2001}, pages = {737--740}, url = {://WOS:000176920100189} } |
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Tapia-Coral, S.C., Luizao, F.J., Wandelli, E. and Fernandes, E.C.M. | Carbon and nutrient stocks in the litter layer of agroforestry systems in central Amazonia, Brazil | 2005 | Agroforestry Systems Vol. 65(1), pp. 33-42 |
article | DOI URL |
Abstract: Both second-growth and agroforestry systems (AFs) have the potential for recovering thousands of abandoned pasturelands in Amazon. The AFs may do it faster and, at the same time, produce direct economic benefits for farmers. Improved nutrient recycling may be expected due to distinctive litter production in AFs, but lacks experimental data yet. The stocks of carbon and nutrients of the litter layer under different agroforestry systems ( AFs) were investigated at an abandoned pasture site, 60 km north of Manaus. The experimental design consisted of three blocks, with five treatments: four different types of 5-year-old AFs and a secondary forest ( CAP). Litter layer was sampled in the wet and dry seasons, sorted according to the predominant plant species and analysed for carbon and nutrient concentrations. The litter layer in the control plots was much larger than in the AFs, and thus, the carbon stocks in the litter layer of the control (wet = 489 g m(2); dry = 783 g m(2)) were larger than in the AFs. However, due to a clearly higher concentration of nutrients in the litter from the AFs, some nutrient stocks were similar or even greater than in the control. The planted timber species and the green manures were important sources of K and Ca to the litter layer while the peach-palm was an important source of Mg. In general, the litter of AFs had lower C: nutrient ratios than the litter in the secondary forest control, indicating a faster nutrient recycling in the AFs. | |||||
BibTeX:
@article{tapia-coral_carbon_2005, author = {Tapia-Coral, S. C. and Luizao, F. J. and Wandelli, E. and Fernandes, E. C. M.}, title = {Carbon and nutrient stocks in the litter layer of agroforestry systems in central Amazonia, Brazil}, journal = {Agroforestry Systems}, year = {2005}, volume = {65}, number = {1}, pages = {33--42}, url = {://WOS:000229000700004 http://www.springerlink.com/content/x2x34711m7644764/fulltext.pdf}, doi = {https://doi.org/10.1007/s10457-004-5152-0} } |
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Tapia-Coral, S.C., Luizao, F.J., Barros, E., Pashanasi, B. and del Castillo, D. | Effect of Pontoscolex corethrurus Muller, 1857 (Oligochaeta : Glossoscolecidae) inoculation on litter weight loss and soil nitrogen in mesocosms in the Peruvian Amazon | 2006 | Caribbean Journal of Science Vol. 42(3), pp. 410-418 |
article | URL |
Abstract: A glasshouse experiment was set up at the Centro de Investigaciones de Jenaro Herrera in the Peruvian Amazon to determine the effect of Pontoscolex corethrurus inoculation on litter weight loss and soil inorganic nitrogen (NH4+ and NO3-). The soils in mesocosms were covered by leaf litter from two timber trees, Cedrelinga catenaeformis, Simarouba amara and mixture of both. The experiment lasted one year, evaluating three treatments: inoculation of juvenile P. corethrurus (T1); inoculation of adult P. corethrurus (T2); and, without earthworms (T3). Four replications were used for each litter type: Cedrelinga, Simarouba, and a mixture of both. The following parameters were determined: the weight of the remaining litter, the density of juvenile and adult P. corethurus, earthworm activity based on faecal pellets, carbon and macro-nutrient concentrations in faecal pellets, and soil inorganic nitrogen. There was a higher density of adult P. corethrurus in the Simarouba litter; however, earthworm biomass was similar across treatments and litter types. The inoculation of juvenile and adult P. corethrurus considerably increased NH4+ and NO3- concentrations in the soil. This was particularly true for adult earthworms, the most effective in mineralizing nitrogen. Pontoscolex corethrurus had a positive effect on litter weight loss and Cedrelinga litter (with higher nutrient concentration) lost more weigh (91.1%) than that of Simarouba (73.3%). Thus, the addition of fast-decomposing and high-quality litter or green cover to tropical soils could increase the release of nitrogen and the soil mineralization and nitrification potentials. | |||||
BibTeX:
@article{tapia-coral_effect_2006, author = {Tapia-Coral, Sandra C. and Luizao, Flavio J. and Barros, Eleusa and Pashanasi, Beto and del Castillo, Dennis}, title = {Effect of Pontoscolex corethrurus Muller, 1857 (Oligochaeta : Glossoscolecidae) inoculation on litter weight loss and soil nitrogen in mesocosms in the Peruvian Amazon}, journal = {Caribbean Journal of Science}, year = {2006}, volume = {42}, number = {3}, pages = {410--418}, url = {://WOS:000245937900016} } |
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Tapia-Coral, S.C., Costa, J.R.d., Inuma, J.C., Morais, J.W., Wandelli, E.V. and Luizão, F.J. | Serviços Ambientais em Ecossistemas Manejados por Agricultores Familiares do Assentamento Tarumã-Mirim, Amazonas [BibTeX] |
2008 | , pp. 36p.School: INPA | techreport | |
BibTeX:
@techreport{tapia-coral_servicos_2008, author = {Tapia-Coral, Sandra C. and Costa, Joanne Régis da and Inuma, Jomber Chota and Morais, José Wellington and Wandelli, Elisa Vieira and Luizão, Flávio J.}, title = {Serviços Ambientais em Ecossistemas Manejados por Agricultores Familiares do Assentamento Tarumã-Mirim, Amazonas}, school = {INPA}, year = {2008}, pages = {36p.}, note = {Edition: FAPEAM} } |
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Tapia-Coral Luizão, F.&.W.E.S. | Macrofauna da liteira em sistemas agroflorestais sobre pastagens abandonadas na Amazônia central [BibTeX] |
1999 | Acta Amazonica Vol. 29, pp. 477-495 |
article | |
BibTeX:
@article{tapia-coral_macrofauna_1999, author = {Tapia-Coral, Luizão, F.J. & Wandelli, E.V., S.C.}, title = {Macrofauna da liteira em sistemas agroflorestais sobre pastagens abandonadas na Amazônia central}, journal = {Acta Amazonica}, year = {1999}, volume = {29}, pages = {477--495} } |
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Tapia-Coral, S., Luizão, F., Pashanasi, B., Castillo, D. and Lavelle, P. | Influencia da massa e nutrientes da liteira sobre a composição dos macro-invertebrados em plantios florestais na Amazônia Peruana. [BibTeX] |
2014 | Folia Amazonica Vol. 23, pp. 171-186 |
article | |
BibTeX:
@article{tapia-coral_influencia_2014, author = {Tapia-Coral, S. and Luizão, F.J. and Pashanasi, B. and Castillo, D. and Lavelle, P.}, title = {Influencia da massa e nutrientes da liteira sobre a composição dos macro-invertebrados em plantios florestais na Amazônia Peruana.}, journal = {Folia Amazonica}, year = {2014}, volume = {23}, pages = {171--186} } |
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Tapajós, R., Machado, W.B., Santana, R., Vale, R., Ferreira Junior M. J. A., R. and Silva | Análise das características do vento sobre a Floresta Nacional do Tapajós, Pará, Brasil [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 204-204 |
article | |
BibTeX:
@article{tapajos_alise_2016, author = {Tapajós, R. ; Machado, W. B. ; Santana, R. ; Vale, R. ; Ferreira Junior, M. J. A., R. ; Silva}, title = {Análise das características do vento sobre a Floresta Nacional do Tapajós, Pará, Brasil}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {204--204} } |
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Tapajós, R., Machado, W., Aguiar, D., Bota, B., Weidemann, K., Furtado Neto, A., Silva, R.d. and Fitzjarrald, D. | Brisa do rio tapajós e sua influência na atmosfera [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 470 - 472 |
article | |
BibTeX:
@article{tapajos_brisa_2013, author = {Tapajós, Raphael and Machado, Wilderclay and Aguiar, Diego and Bota, Bruno and Weidemann, Kenia and Furtado Neto, Alírio and Silva, Rodrigo da and Fitzjarrald, David}, title = {Brisa do rio tapajós e sua influência na atmosfera}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {470 -- 472} } |
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Tanaka, L.M.d.S., Satyamurty, P. and Machado, L.A.T. | Diurnal variation of precipitation in central Amazon Basin [BibTeX] |
2014 | International Journal of Climatology Vol. 34(13), pp. 3574-3584 |
article | DOI |
BibTeX:
@article{tanaka_diurnal_2014, author = {Tanaka, L. M. d. S. and Satyamurty, P. and Machado, L. A. T.}, title = {Diurnal variation of precipitation in central Amazon Basin}, journal = {International Journal of Climatology}, year = {2014}, volume = {34}, number = {13}, pages = {3574--3584}, doi = {https://doi.org/10.1002/joc.3929} } |
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Talbot, S.L., Lopez-Gonzalez, G., Brienen, R.J., Monteagudo, A., Baker, T.R., Feldpausch, T.R., Malhi, Y., Vanderwel, M., Araujo Murakami, A., Arroyo, L.P., Chao, K.-J., Erwin, T., Van Der Heijden, G., Keeling, H., Killeen, T., Neill, D., Núñez Vargas, P., Parada Gutierrez, G.A., Pitman, N., Quesada, C.A., Silveira, M., Stropp, J., Phillips Oliver L., J. and Lewis | Methods to estimate aboveground wood productivity from long-term forest inventory plots [BibTeX] |
2014 | Forest Ecology and Management Vol. 320, pp. 30-38 |
article | |
BibTeX:
@article{talbot_methods_2014, author = {Talbot, Simon L. ; Lopez-Gonzalez, Gabriela ; Brienen, Roel J.W. ; Monteagudo, Abel ; Baker, Timothy R. ; Feldpausch, Ted R. ; Malhi, Yadvinder ; Vanderwel, Mark ; Araujo Murakami, Alejandro ; Arroyo, Luzmila P. ; Chao, Kuo-Jung ; Erwin, Terry ; Van Der Heijden, Geertje ; Keeling, Helen ; Killeen, Tim ; Neill, David ; Núñez Vargas, Percy ; Parada Gutierrez, Germaine Alexander ; Pitman, Nigel ; Quesada, Carlos Alberto ; Silveira, Marcos ; Stropp, Juliana ; Phillips, Oliver L., Joey ; Lewis}, title = {Methods to estimate aboveground wood productivity from long-term forest inventory plots}, journal = {Forest Ecology and Management}, year = {2014}, volume = {320}, pages = {30--38} } |
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Tagliavini, E., Moretti, F., Decesari, S., Facchini, M.C., Fuzzi, S. and Maenhaut, W. | Functional group analysis by HNMR/chemical derivatization for the characterization of organic aerosol from the SMOCC field campaign | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 1003-1019 |
article | URL |
Abstract: Water soluble organic compounds (WSOC) in aerosol samples collected in the Amazon Basin in a period encompassing the middle/late dry season and the beginning of the wet season, were investigated by H NMR spectroscopy. HiVol filter samples (PM2.5 and PM textgreater 2.5) and size-segregated samples from multistage impactor were subjected to H NMR characterization. The H NMR methodology, recently developed for the analysis of organic aerosol samples, has been improved by exploiting chemical methylation of carboxylic groups with diazomethane, which allows the direct determination of the carboxylic acid content of WSOC. The content of carboxylic carbons for the different periods and sizes ranged from 12% to 20% of total measured carbon depending on the season and aerosol size, with higher contents for the fine particles in the transition and wet periods with respect to the dry period. A comprehensive picture is presented of WSOC functional groups in aerosol samples representative of the biomass burning period, as well as of transition and semi-clean atmospheric conditions. A difference in composition between fine (PM2.5) and coarse (PM textgreater 2.5) size fractions emerged from the NMR data, the former showing higher alkylic content, the latter being largely dominated by R-O-H (or R-O-R') functional groups. Very small particles (textless0.14 mu m), however, present higher alkyl-chain content and less oxygenated carbons than larger fine particles (0.42-1.2 mu m). More limited variations were found between the average compositions in the different periods of the campaign. | |||||
BibTeX:
@article{tagliavini_functional_2006, author = {Tagliavini, E. and Moretti, F. and Decesari, S. and Facchini, M. C. and Fuzzi, S. and Maenhaut, W.}, title = {Functional group analysis by HNMR/chemical derivatization for the characterization of organic aerosol from the SMOCC field campaign}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {1003--1019}, url = {://WOS:000236364700001} } |
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Tadesse, A. and Anagnostou, E.N. | A statistical approach to ground radar-rainfall estimation | 2005 | Journal of Atmospheric and Oceanic Technology Vol. 22(11), pp. 1720-1732 |
article | DOI URL |
Abstract: This paper presents development of a statistical procedure for estimation of ensemble rainfall fields from a combination of ground radar observations and in situ rain gauge measurements. The uncertainty framework characterizes radar-rainfall estimation algorithm limitation accounting for rain gauge sampling uncertainty. The procedure is applied on a multicomponent rainfall estimation algorithm, which utilizes a rain-path attenuation correction technique, a power-law reflectivity-to-rainfall (Z-R) relationship, and a parameter to differentiate between convective (C) and stratiform (S) regimes in the Z-R conversion. Uncertainty is explicitly accounted for by evaluating the algorithm's parameter set posterior probability density function (known as parameters' equifinality) on the basis of the Generalized Likelihood Uncertainty Estimation (GLUE) framework. The study is facilitated by NASA's C-band Doppler radar [named the Tropical Ocean Global Atmosphere (TOGA)] observations and four dense rain gauge clusters available from the Tropical Rainfall Measuring Mission (TRMM)-Large-Scale-Biosphere-Atmosphere (LBA) experiment, conducted between January and February of 1999 in Southwest Amazon. Statistics are proposed for jointly evaluating the wideness of radar retrieval uncertainty limits [uncertainty ratio (UR)] and the percentage of observations that fall within those error bounds [exceedance ratio (ER)]. Results show that the parameter range selected in GLUE could characterize the radar-rainfall estimation uncertainty. Combined assessment of UR and ER for a varying range of parameters' equifinality provides an objective basis for comparing rain retrieval algorithms and determining uncertainty bounds. Ensemble radar-rainfall fields derived on the basis of this procedure can be used to statistically assess satellite rain retrieval algorithms and derive ensemble hydrologic predictions driven by radar-rainfall input (e. g., runoff and soil moisture). | |||||
BibTeX:
@article{tadesse_statistical_2005, author = {Tadesse, A. and Anagnostou, E. N.}, title = {A statistical approach to ground radar-rainfall estimation}, journal = {Journal of Atmospheric and Oceanic Technology}, year = {2005}, volume = {22}, number = {11}, pages = {1720--1732}, url = {://WOS:000233993900007}, doi = {https://doi.org/10.1175/jtech1796.1} } |
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Swenson, B., Pither, J., Kerkhoff, A., Boyle, B., Weiser, M., Elser, J., Fagan, W., Forero-Montaña, J., Fyllas, N., Kraft, N., Lake, J., Moles, A., PATIÑO, S., Phillips, O., Price, C., Reich, P., Quesada, C., Stegen, J., Valencia, R., Wright, I., Wright, S., Andelman, S., Joergensen, P., Lacher Jr, T., et al. , N. and Enquist | The biogeography and filtering of woody plant functional diversity in North and South America [BibTeX] |
2012 | Global Ecology and Biogeography Vol. 21, pp. 798-808 |
article | |
BibTeX:
@article{swenson_biogeography_2012, author = {Swenson, B.J.; Pither, J.; Kerkhoff, A.J.; Boyle, B.; Weiser, M.D.; Elser, J.J.; Fagan, W.F.; Forero-Montaña, J.; Fyllas, N.; Kraft, N.J.B.; Lake, J.K.; Moles, A.T.; PATIÑO, S.; Phillips, O.L.; Price, C.A.; Reich, P.B.; Quesada, C.A.; Stegen, J.C.; Valencia, R.; Wright, I.J.; Wright, S.J.; Andelman, S.; Joergensen, P.M.; Lacher Jr, T.E.; et al., N.G.; Enquist}, title = {The biogeography and filtering of woody plant functional diversity in North and South America}, journal = {Global Ecology and Biogeography}, year = {2012}, volume = {21}, pages = {798--808} } |
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Svierzoski, N.D.S., Lopes, A.G., Ruezzene, C.B., Gomes, J.d.B. and Webler, A.D. | Componentes do balanço de energia em área de pastagem na Amazônia Ocidental / Energy balance components in a pasture area in Western Amazon | 2 | Brazilian Journal of Development Vol. 7(2), pp. 19683-19694 |
article | DOI URL |
Abstract: <p>A conversão de áreas de floresta em áreas de pastagem levanta discussões sobre as possíveis mudanças que esse ato pode provocar no clima, tanto regional, quanto global. Dessa forma, o presente estudo buscou analisar os componentes do balanço de energia nos quatro períodos do ano de 2010 em uma área de pastagem localizada no sudoeste da Amazônia. Os dados foram coletados por instrumentos instalados em uma torre meteorológica do Programa LBA e calculados a partir do método de covariância de vórtices turbulentos. Para os períodos úmido, úmido-seco, seco e seco-úmido a média em W m<sup>-2</sup> de LE foi de 95,4; 84,5; 66,86; 87,9 e de H foi de 17,5; 23,6; 31,6; 31,4 respectivamente. A análise dos dados permitiu o entendimento da variabilidade dos componentes do balanço de energia, e ainda, os possíveis efeitos das mudanças no uso da terra amazônica.</p> | |||||
BibTeX:
@article{svierzoski_componentes_2, author = {Svierzoski, Nicoly Dal Santo and Lopes, Aricson Garcia and Ruezzene, Camila Bermond and Gomes, Josiane de Brito and Webler, Alberto Dresch}, title = {Componentes do balanço de energia em área de pastagem na Amazônia Ocidental / Energy balance components in a pasture area in Western Amazon}, journal = {Brazilian Journal of Development}, year = {2}, volume = {7}, number = {2}, pages = {19683--19694}, note = {Section: Original Papers}, url = {https://brazilianjournals.com/ojs/index.php/BRJD/article/view/25259}, doi = {https://doi.org/10.34117/bjdv7n2-557} } |
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Suni, T., Guenther, A., Hansson, H., Kulmala, M. and M.O. Andreae P. Artaxo, E.B.M.B.L.G.P.K.N.N.-D.M...R.A.R.D.R.S.S.A.A. | The significance of land–atmosphere interactions in the Earth system—iLEAPS achievements and perspectives [BibTeX] |
2015 | Anthropocene | article | DOI |
BibTeX:
@article{suni_significance_2015, author = {Suni, T. and Guenther, A. and Hansson, H.C. and Kulmala, M. and M.O. Andreae, P. Artaxo, E. Blyth, M. Brus, L. Ganzeveld, P. Kabat, Nde. Noblet-Ducoudre M, . Reichstein A. Reissell, D. Rosenfeld, S. Seneviratne., A. Arneth}, title = {The significance of land–atmosphere interactions in the Earth system—iLEAPS achievements and perspectives}, journal = {Anthropocene}, year = {2015}, note = {Edition: http://www.sciencedirect.com/science/article/pii/S2213305415300254}, doi = {https://doi.org/10.1016/j.ancene.2015.12.001} } |
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Summers, P.M., Browder, J.O. and Pedlowski, M.A. | Tropical forest management and silvicultural practices by small farmers in the Brazilian Amazon: recent farm-level evidence from Rondonia | 2004 | Forest Ecology and Management Vol. 192(2-3), pp. 161-177 |
article | DOI URL |
Abstract: This paper examines forest management and silvicultural practices of small colonist landholders in the western Brazilian Amazon state of Rondonia. Although recent colonists in the Amazon are widely acknowledged as key agents of tropical forest conversion, relatively little is known of their uses of primary and secondary forest patches and the degree to which these farmers plant trees as part of their land use strategies. Based on longitudinal survey data drawn from three different colonist settlements in 1992 and 2002, this paper explores the range of small farmer's uses of forests and fallows that may indicate future trends in forest management. We also examine the links between forest extraction and tree planting and the factors that may influence these practices. We found that nearly 40% of the farmers surveyed regularly extract useful products from their forests. We examine the types and quantities of timber and non-timber forest products extracted by small farmers over this 10-year study period, and reasons given by them for managing or not managing their forest patches. Forest extractor households were characterized as having a smaller percentage of their land deforested and smaller cattle herds. In addition, we found that roughly 30% of the small farmers surveyed planted trees on their farms during this 10-year study period. Results of statistical analysis (ANOVA and chi square contingency tests) to identify factors that correlate with tree planting behavior indicate that tree planters own larger plots, reside longer on those plots, have a larger number of working age household members, and secure land titles. They were also more likely to participate in social organizations. We conclude that despite ongoing deforestation processes in the region, natural forest use is an important subsistence activity for many small farmers and that many farmers are planting and managing tree species for both short-term products and as long-term investments. (C) 2004 Published by Elsevier B.V. | |||||
BibTeX:
@article{summers_tropical_2004, author = {Summers, P. M. and Browder, J. O. and Pedlowski, M. A.}, title = {Tropical forest management and silvicultural practices by small farmers in the Brazilian Amazon: recent farm-level evidence from Rondonia}, journal = {Forest Ecology and Management}, year = {2004}, volume = {192}, number = {2-3}, pages = {161--177}, url = {://WOS:000221318300003}, doi = {https://doi.org/10.1016/j.foreco.2003.12.016} } |
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Stropp, J., van der Sleen, P., Quesada, C.A. and ter Steege, H. | Herbivory and habitat association of tree seedlings in lowland evergreen rainforest on white-sand and terra-firme in the upper Rio Negro [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 255-265 |
article | |
BibTeX:
@article{stropp_herbivory_2014, author = {Stropp, Juliana and van der Sleen, Peter and Quesada, Carlos A. and ter Steege, Hans}, title = {Herbivory and habitat association of tree seedlings in lowland evergreen rainforest on white-sand and terra-firme in the upper Rio Negro}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {255--265} } |
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Stropp, J., ter Steege, H. and Malhi, Y. | Disentangling regional and local tree diversity in the Amazon | 2009 | Ecography Vol. 32(1), pp. 46-54 |
article | DOI URL |
Abstract: We analyzed the most extensive data set of tree inventory plots spread over the complete Amazon basin and Guiana shield. We aimed to separate the regional and local tree alpha-diversity to investigate the drivers of diversity at the relevant scale. Our results are consistent with the partitioning of total tree alpha-diversity into regional and local components, which are controlled by evolutionary- and ecological processes, respectively. Regional diversity is correlated with palaeo-climatic stability (31%), and long-term large-scale ecosystem dynamics (14%), as represented by the age of the geological formation. Both mechanisms contribute to high diversity in the central to western Amazon. Actual rainfall seasonality is correlated with regional tree diversity to a certain extent (19%), but we argue that this is of little consequence for the evolutionary drivers of the regional species pool. Frequency of disturbance is the main process driving local diversity, although its explanatory power is relatively small (17%). | |||||
BibTeX:
@article{stropp_disentangling_2009, author = {Stropp, Juliana and ter Steege, Hans and Malhi, Yadvinder}, title = {Disentangling regional and local tree diversity in the Amazon}, journal = {Ecography}, year = {2009}, volume = {32}, number = {1}, pages = {46--54}, url = {://WOS:000264880300006}, doi = {https://doi.org/10.1111/j.1600-0587.2009.05811.x} } |
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Strong, C., Fuentes, J.D., Garstang, M. and Betts, A.K. | Daytime cycle of low-level clouds and the tropical convective boundary layer in southwestern Amazonia | 2005 | Journal of Applied Meteorology Vol. 44(10), pp. 1607-1619 |
article | DOI URL |
Abstract: During the wet season in the southwestern Amazon region, daytime water transport out of the atmospheric mixed layer into the deeper atmosphere is shown to depend upon cloud amounts and types and synoptic-scale velocity fields. Interactions among clouds, convective conditions, and subcloud-layer properties were estimated for two dominant flow regimes observed during the 1999 Tropical Rainfall Measuring Mission component of the Brazilian Large-Scale Biosphere-Atmosphere (TRMM-LBA) field campaign. During daytime the cloud and subcloud layers were coupled by radiative, convective, and precipitation processes. The properties of cloud and subcloud layers varied according to the different convective influences of easterly versus westerly lower-tropospheric flows. The most pronounced flow-regime effects on composite cloud cycles occurred under persistent lower-tropospheric flows, which produced strong convective cloud growth with a near absence of low-level stratiform clouds, minimal cumulative attenuation of incoming solar irradiance (similar to 25%), rapid daytime mixed-layer growth (textgreater 100 m h(-1)), and boundary layer drying (0.22 g kg(-1) h(-1)), high convective velocities (textgreater 1.5 m s(-1)), high surface buoyancy flux (textgreater 200 W m(-2)) and high latent heat flux (600 W m(-2)) into cloud layer. In contrast, persistent westerly flows were less convective, showing a strong morning presence of low-level stratiform genera (textgreater 0.9 cloud amount), greater cumulative attenuation of incoming solar irradiance (similar to 47%), slower mixed-layer growth (textless 50 m h(-1)) with a slight tendency for mixed-layer moistening, and a delayed peak in the low-level cumuliform cloud cycle (2000 versus 1700 UTC). The results reported in this article indicate that numerical models need to account for cloud amounts and types when estimating water vapor transport to the cloud layer. | |||||
BibTeX:
@article{strong_daytime_2005, author = {Strong, C. and Fuentes, J. D. and Garstang, M. and Betts, A. K.}, title = {Daytime cycle of low-level clouds and the tropical convective boundary layer in southwestern Amazonia}, journal = {Journal of Applied Meteorology}, year = {2005}, volume = {44}, number = {10}, pages = {1607--1619}, url = {://WOS:000233034500008}, doi = {https://doi.org/10.1175/jam2266.1} } |
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Stoy, P., Gerken, T., Fuentes, J.D., Nascimento dos Santos, R.M., Randow, C.V., Maia, J.M.F., Manzi, A. and Chamecki, ..M. | Energy Balance Closure in a tropical forest: contributions of turbulent 18 exchange and ecosystem heat storage [BibTeX] |
2016 | Ciência & Natura Vol. 38(Ed. Especial- IX Workshop Brasileiro de Micrometeorologia), pp. 548 - 551 |
article | |
BibTeX:
@article{stoy_energy_2016, author = {Stoy, P.C. and Gerken, T. and Fuentes, J. D. and Nascimento dos Santos, R. M. and Randow, C. Von and Maia, J. M. F. and Manzi, A. and Chamecki, . M.}, title = {Energy Balance Closure in a tropical forest: contributions of turbulent 18 exchange and ecosystem heat storage}, journal = {Ciência & Natura}, year = {2016}, volume = {38}, number = {Ed. Especial- IX Workshop Brasileiro de Micrometeorologia}, pages = {548 -- 551} } |
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Stith, J.L., Dye, J.E., Bansemer, A., Heymsfield, A.J., Grainger, C.A., Petersen, W.A. and Cifelli, R. | Microphysical observations of tropical clouds | 2002 | Journal of Applied Meteorology Vol. 41(2), pp. 97-117 |
article | DOI URL |
Abstract: The results from airborne in situ sampling of convective tropical storms in the Amazon and Kwajalein are presented. Three cases from the Amazon and two from Kwajalein are compared and provide examples of the much larger dataset that was obtained from field campaigns in these two regions during 1999. The strength of the updraft was a major factor in determining the microphysical characteristics of hydrometeors. Weak updrafts exhibited a well-developed warm rain process by the time droplets had reached the freezing level. Stronger updrafts (textgreater5 m s(-1)) contained smaller droplets or ice particles at cloud midlevels than regions with the weaker updrafts. Significant supercooled liquid water was found only at temperatures warmer than -12degreesC, although traces of liquid water were observed at temperatures as cold as -18degreesC. In deep stratiform anvil regions, aggregation was observed to be a major growth mechanism. These clouds did not contain appreciable amounts of supercooled water. Clouds with similar updrafts in the Amazon and Kwajalein exhibited similar particle types and concentrations. The implications of these results for current Tropical Rainfall Measuring Mission (TRMM) investigations are discussed. | |||||
BibTeX:
@article{stith_microphysical_2002, author = {Stith, J. L. and Dye, J. E. and Bansemer, A. and Heymsfield, A. J. and Grainger, C. A. and Petersen, W. A. and Cifelli, R.}, title = {Microphysical observations of tropical clouds}, journal = {Journal of Applied Meteorology}, year = {2002}, volume = {41}, number = {2}, pages = {97--117}, url = {://WOS:000173316500001}, doi = {https://doi.org/10.1175/1520-0450(2002)041%3C0097:mootc%3E2.0.co;2} } |
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Stickler, C.M., Nepstad, D.C., Coe, M.T., McGrath, D.G., Rodrigues, H.O., Walker, W.S., Soares-Filho, B.S. and Davidson, E.A. | The potential ecological costs and cobenefits of REDD: a critical review and case study from the Amazon region | 2009 | Global Change Biology Vol. 15(12), pp. 2803-2824 |
article | DOI URL |
Abstract: The United Nations climate treaty may soon include a mechanism for compensating tropical nations that succeed in reducing carbon emissions from deforestation and forest degradation, source of nearly one fifth of global carbon emissions. We review the potential for this mechanism [reducing emissions from deforestation and degradation (REDD)] to provoke ecological damages and promote ecological cobenefits. Nations could potentially participate in REDD by slowing clear-cutting of mature tropical forest, slowing or decreasing the impact of selective logging, promoting forest regeneration and restoration, and expanding tree plantations. REDD could also foster efforts to reduce the incidence of forest fire. Potential ecological costs include the accelerated loss (through displaced agricultural expansion) of low-biomass, high-conservation-value ecosystems, and substitution of low-biomass vegetation by monoculture tree plantations. These costs could be avoided through measures that protect low-biomass native ecosystems. Substantial ecological cobenefits should be conferred under most circumstances, and include the maintenance or restoration of (1) watershed functions, (2) local and regional climate regimes, (3) soils and biogeochemical processes, (4) water quality and aquatic habitat, and (5) terrestrial habitat. Some tools already being developed to monitor, report and verify (MRV) carbon emissions performance can also be used to measure other elements of ecosystem function, making development of MRV systems for ecological cobenefits a concrete possibility. Analysis of possible REDD program interventions in a large-scale Amazon landscape indicates that even modest flows of forest carbon funding can provide substantial cobenefits for aquatic ecosystems, but that the functional integrity of the landscape's myriad small watersheds would be best protected under a more even spatial distribution of forests. Because of its focus on an ecosystem service with global benefits, REDD could access a large pool of global stakeholders willing to pay to maintain carbon in forests, thereby providing a potential cascade of ecosystem services to local stakeholders who would otherwise be unable to afford them. | |||||
BibTeX:
@article{stickler_potential_2009, author = {Stickler, Claudia M. and Nepstad, Daniel C. and Coe, Michael T. and McGrath, David G. and Rodrigues, Hermann O. and Walker, Wayne S. and Soares-Filho, Britaldo S. and Davidson, Eric A.}, title = {The potential ecological costs and cobenefits of REDD: a critical review and case study from the Amazon region}, journal = {Global Change Biology}, year = {2009}, volume = {15}, number = {12}, pages = {2803--2824}, url = {://WOS:000271710300001}, doi = {https://doi.org/10.1111/j.1365-2486.2009.02109.x} } |
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Steudler, P.A., Garcia-Montiel, D.C., Piccolo, M.C., Neill, C., Melillo, J.M., Feigl, B.J. and Cerri, C.C. | Trace gas responses of tropical forest and pasture soils to N and P fertilization | 2002 | Global Biogeochemical Cycles Vol. 16(2) |
article | DOI URL |
Abstract: [1] We measured the responses of nitric oxide (NO), nitrous oxide (N2O) and carbon dioxide (CO2) to nitrogen (N) and/or phosphorus (P) fertilization in a mature moist tropical forest and an 11-year-old pasture in the Brazilian Amazon. Nitrogen was applied in two forms, ammonium (NH4+) and nitrate (NO3-). In the forest, NO emissions increased by 4 to 9 times the controls in the NH4+ amended plots. Nitrous oxide emissions showed a small response only in the NH4+ amended plots. In the pasture, NO emissions during the first 7 days after fertilization with either form of N were about twice those in the control plots. Nitrous oxide emissions increased more than 18 times the controls in the NO3- amended plots 1 day after fertilization. The estimated yields of total nitrogen oxide loss from the forest were between 0.2 and 1.6% of the applied nitrogen, predominately as NO. Pasture yields were greater, up to 2.8% of the applied nitrogen, predominately as N2O. In the context of Rondonia and other regions in the Amazon Basin, pasture management practices are changing to include increased use of fertilizer, particularly in older pastures that have lower NO and N2O emissions than the original intact forests. This may lead to large short-term releases of N2O and alter the future N2O emissions from the Basin. | |||||
BibTeX:
@article{steudler_trace_2002, author = {Steudler, P. A. and Garcia-Montiel, D. C. and Piccolo, M. C. and Neill, C. and Melillo, J. M. and Feigl, B. J. and Cerri, C. C.}, title = {Trace gas responses of tropical forest and pasture soils to N and P fertilization}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {2}, url = {://WOS:000178887900005}, doi = {https://doi.org/10.1029/2001gb001394} } |
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Sternberg, L.D., Moreira, M.Z., Martinelli, L.A., Victoria, R.L., Barbosa, E.M., Bonates, L.C.M. and Nepstad, D. | The relationship between O-18/O-16 and C-13/C-12 ratios of ambient CO2 in two Amazonian tropical forests | 1998 | Tellus Series B-Chemical and Physical Meteorology Vol. 50(4), pp. 366-376 |
article | DOI URL |
Abstract: Oxygen and carbon isotopic compositions of ambient carbon dioxide in two tropical forests in the Amazonian basin were determined at the beginning and the end of the dry season. One site, Fazenda Vitoria, is typical of a seasonal forest with a pronounced dry season from May to November whereas the other site, Reserva Ducke, has a milder dry season. Samples collected at night revealed that in the beginning of the dry season, when the forest is still relatively wet, isotopic exchange between carbon dioxide and wet surfaces or fog is possible. Oxygen isotope ratios of ambient carbon dioxide collected during the day were correlated with the carbon isotope ratios. These correlations are representative of the mixing line between tropospheric and respired CO2. The mixing lines were used to extrapolate the delta(18)O values of soil-respired CO2. These values were compared with those derived from the isotopic composition of bulk soil water (as reflected by plant stem water) and a diffusion isotopic effect of 8.8 parts per thousand,. It was observed that delta(18)O values of respired CO2 derived by extrapolation were greater than those calculated by using delta(18)O values of bulk soil water and the associated diffusion isotope effect. The results show that in tropical forests, assumptions used in previous studies of temperate regions to derive the oxygen isotopic composition of respired CO2 do not hold. | |||||
BibTeX:
@article{sternberg_relationship_1998, author = {Sternberg, L. D. and Moreira, M. Z. and Martinelli, L. A. and Victoria, R. L. and Barbosa, E. M. and Bonates, L. C. M. and Nepstad, D.}, title = {The relationship between O-18/O-16 and C-13/C-12 ratios of ambient CO2 in two Amazonian tropical forests}, journal = {Tellus Series B-Chemical and Physical Meteorology}, year = {1998}, volume = {50}, number = {4}, pages = {366--376}, url = {://WOS:000076567700004}, doi = {https://doi.org/10.1034/j.1600-0889.1998.t01-3-00004.x} } |
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Sternberg, L., Moreira, M.Z. and Nepstad, D.C. | Uptake of water by lateral roots of small trees in an Amazonian Tropical Forest | 2002 | Plant and Soil Vol. 238(1), pp. 151-158 |
article | DOI URL |
Abstract: A pulse chase technique was used to determine depth and breath of plant water uptake in an Amazonian evergreen forest. Two 2x2 m(2) plots were irrigated with deuterated water. The deuterium pulse, measured as deltaD values of soil and plant sap water, was followed in the soil water profile and in stem water of small trees inside and up to 12 m away from the irrigated plots. The deuterium pulse percolation rate was measured to be approximately 0.25 m/month and similar to a previous study in central Amazon. There was little horizontal movement of label through the soil profile; allowing us to conclude that any evidence of label in plants away from the irrigation plots implies the presence of their roots inside the irrigation plots. The bulk of label uptake occurred in plants inside the irrigation plots. However, there were a few individuals as far as 10 m away picking up the label from the irrigation plots. This labeling pattern leads to the conclusion that small trees may have a core of water absorbing roots close to their main trunk, with some roots meandering far from their main trunk. | |||||
BibTeX:
@article{sternberg_uptake_2002, author = {Sternberg, Ldsl and Moreira, M. Z. and Nepstad, D. C.}, title = {Uptake of water by lateral roots of small trees in an Amazonian Tropical Forest}, journal = {Plant and Soil}, year = {2002}, volume = {238}, number = {1}, pages = {151--158}, url = {://WOS:000174002500015}, doi = {https://doi.org/10.1023/a:1014214404699} } |
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Steininger, M.K., Tucker, C.J., Townshend, J.R.G., Killeen, T.J., Desch, A., Bell, V. and Ersts, P. | Tropical deforestation in the Bolivian Amazon | 2001 | Environmental Conservation Vol. 28(2), pp. 127-134 |
article | URL |
Abstract: The distributions of forest and deforestation throughout the tropics are poorly known despite their importance to regional biodiversity and global climate and biodiversity. Deforestation estimates based on surveys or sampling have large errors, and high-resolution, wall-to-wall mapping of tropical forests is necessary to assess the impacts of fragmentation. Landsat satellite images from the mid-1980s and early 1990s were thus used to map closed-canopy tropical forest extent and anthropogenic deforestation in an approximately 700 000 km(2) area of Amazonian Bolivia with precipitation textgreater 1000mm yr(-1). Total potential forest cover extent, including tropical deciduous forest, was 448 700 km(2), while the area of natural non-forest formations was 245 100 km(2). The area deforested was 15 500 km(2) in the mid-1980s and 24 700 km(2) by the early 1990s. The rate of tropical deforestation in the forest zone of Bolivia with textgreater 1000 mm yr(-1) precipitation below 1500 m elevation and north of 19 degrees S, was 1529 km(2) yr(-1) from 1985-1986 to 1992-1994. Our estimates of deforestation are significantly lower than those reported by the Food and Agriculture Organization of the United Nations (FAO). We document a spatially-concentrated 'deforestation zone' in Santa Cruz where textgreater 60% of the Bolivian deforestation has occurred. These results indicate that the rate of deforestation in Bolivia has been rapid despite a relatively small human population, and, as in Brazil, clearance has concentrated in the more deciduous forests. | |||||
BibTeX:
@article{steininger_tropical_2001, author = {Steininger, M. K. and Tucker, C. J. and Townshend, J. R. G. and Killeen, T. J. and Desch, A. and Bell, V. and Ersts, P.}, title = {Tropical deforestation in the Bolivian Amazon}, journal = {Environmental Conservation}, year = {2001}, volume = {28}, number = {2}, pages = {127--134}, url = {://WOS:000170219200005} } |
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Steininger, M.K. | Net carbon fluxes from forest clearance and regrowth in the Amazon | 2004 | Ecological Applications Vol. 14(4), pp. S313-S322 |
article | URL |
Abstract: Estimates of net carbon exchange resulting from forest clearance and regrowth were made for three areas in the Brazilian and Bolivian Amazon. The study areas, ranging in size from 600 to 10 000 km(2) include communities that practice a range of land uses from small-scale, rotational agriculture to long-term pasture. Carbon emissions from deforestation were estimated based on rates of deforestation derived from Landsat satellite data and published estimates of mature forest biomass. Estimates of carbon uptake by secondary forest regrowth were based on area estimates from the satellite data and biomass estimates from field surveys. Estimates of carbon emissions from the clearance of secondary forest were included. The total carbon emissions were partitioned into that immediately released by biomass burning during clearance and that from subsequent decomposition and burning of felled biomass. A range of net carbon fluxes from secondary forest regrowth and clearance was estimated by extrapolating land-use patterns in each study area to the entire area of deforested landscape in Amazonian Brazil and Bolivia, and by varying average biomass accumulation rate of regrowing forest and fallow period. Over 60 km(2) of forest were cleared from 1988 to 1905 in each of the Brazilian study areas, and over 940 km(2) were cleared from 1986 to 1996 in the Bolivian study area. This resulted in 30-200 Mg C/yr emitted from biomass burning during deforestation. If the carbon that is committed to subsequent burning and decomposition of felled biomass is included, total committed emissions of 75-650 Mg C/yr resulted from deforestation in each study area. The carbon uptake by secondary forests was 33-435 Mg C/yr. However, emissions from the reclearance of secondary forests were nearly as large: 17-365 Mg C/yr. Extrapolation. of these results to the Brazilian and Bolivian Amazon suggests that, at the national level, carbon uptake by secondary forests offset less than one-fifth of the carbon emissions from deforestation. Despite differences in land-use pattern, average fallow period, and rate of biomass accumulation used in the extrapolation, net carbon uptake by secondary forests was consistently small when compared to the total emissions from deforestation. | |||||
BibTeX:
@article{steininger_net_2004, author = {Steininger, M. K.}, title = {Net carbon fluxes from forest clearance and regrowth in the Amazon}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S313--S322}, url = {://WOS:000223269000025} } |
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Steininger, M.K. | Satellite estimation of tropical secondary forest above-ground biomass: data from Brazil and Bolivia | 2000 | International Journal of Remote Sensing Vol. 21(6-7), pp. 1139-1157 |
article | DOI URL |
Abstract: This paper reports on a test of the ability to estimate above-ground biomass of tropical secondary forest from canopy spectral reflectance using satellite optical data. Landsat Thematic Mapper data were acquired concurrent with field surveys conducted in secondary forest fallows near Manaus, Brazil and Santa Cruz ae la Sierra, Bolivia. Measurements of age and above-ground live biomass were made in 34 regrowth stands. Satellite data were converted to surface reflectances and compared with regrowth stand age, biomass and structural variables. Among the Brazilian stands, significant relationships were observed between middle-infrared reflectance and stand age, height, volume and biomass. The canopy reflectance-biomass relationship saturated at around 15.0 kg m(-2), or over 15 years of age (rtextgreater0.80, ptextless0.01). In the Bolivian study area, no significant relationship between canopy spectral reflectance and biomass was observed. These contrasting results are probably caused by a low Sun angle during the satellite measurements from Bolivia. However, regrowth structural and general compositional differences between the two study areas could explain the lack of a significant relationship in Bolivia. The results demonstrate a current potential for biomass estimation of secondary forests with satellite optical data in some, but not all, tropical regions. A discussion of the potential for regional extrapolation of spectral relationships and future satellite imagery is included. | |||||
BibTeX:
@article{steininger_satellite_2000, author = {Steininger, M. K.}, title = {Satellite estimation of tropical secondary forest above-ground biomass: data from Brazil and Bolivia}, journal = {International Journal of Remote Sensing}, year = {2000}, volume = {21}, number = {6-7}, pages = {1139--1157}, url = {://WOS:000086357700004}, doi = {https://doi.org/10.1080/014311600210119} } |
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Steininger, M.K. | Secondary forest structure and biomass following short and extended land-use in central and southern Amazonia | 2000 | Journal of Tropical Ecology Vol. 16, pp. 689-708 |
article | DOI URL |
Abstract: A study was conducted on the effect of extended land-use on secondary forest biomass accumulation in the Amazon. Structural measurements were made in a series of secondary forest stands, from 4-30 y old, in Brazil and Bolivia. Half of the stands were forest regrowth following clearance and only 1 y of cultivation; the other half were regrowth following 4 y or more of continuous pasture in Brazil and three or more rotations of medium-fallow agriculture in Bolivia. Above-ground live biomass was estimated using published allometric equations. Total biomass ranged from 17 to 207 Mg ha(-1). Biomass of pioneer trees was poorly related to stand age, while that of later-successional trees increased linearly with age. Total biomass accumulation in Bolivia averaged 5.4 Mg ha(-1) y(-1) over the entire age sequence. Biomass accumulation for regrowth following short-term use was not greater than that for regrowth following medium-fallow agriculture. In Brazil, biomass accumulation averaged 9.1 Mg ha(-1) y(-1) over the first 12 y of regrowth and 5.9 Mg ha(-1) y(-1) over the entire age sequence. Biomass accumulation was significantly slower, around 5.0 Mg ha(-1) y(-1), for regrowth following continuous pasture than for regrowth following 1 y of cultivation. | |||||
BibTeX:
@article{steininger_secondary_2000, author = {Steininger, M. K.}, title = {Secondary forest structure and biomass following short and extended land-use in central and southern Amazonia}, journal = {Journal of Tropical Ecology}, year = {2000}, volume = {16}, pages = {689--708}, url = {://WOS:000090119000005}, doi = {https://doi.org/10.1017/s0266467400001656} } |
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Stark, S., Leitold, V., Wu, J.L., Hunter, M., Castilho, C.V.d., Costa, F.C., McMahon, S., Parker, G., Shimabukuro, M.T., Lefsky, M., Keller, M., Alves, L.F., Schietti, J., Shimabukuro, Y., Brandão, D., Woodcock, T., Higuchi, N., Camargo, P.B.d., Oliveira, R.d. and Saleska, S. | Amazon forest carbon dynamics predicted by profiles of canopy leaf area and light environment [BibTeX] |
2012 | Ecology Letters Vol. 15(12), pp. 1406-1414 |
article | |
BibTeX:
@article{stark_amazon_2012, author = {Stark, S.C. and Leitold, V. and Wu, J. L. and Hunter, M.O. and Castilho, C. V. de and Costa, F.R. C. and McMahon, S.M. and Parker, G.G. and Shimabukuro, M. T. and Lefsky, M.A. and Keller, M. and Alves, Luciana F. and Schietti, J. and Shimabukuro, Y.E. and Brandão, D.O. and Woodcock, T.K. and Higuchi, N. and Camargo, Pl. B. de and Oliveira, R.C. de and Saleska, S.R.}, title = {Amazon forest carbon dynamics predicted by profiles of canopy leaf area and light environment}, journal = {Ecology Letters}, year = {2012}, volume = {15}, number = {12}, pages = {1406--1414} } |
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Stark, S., Enquist, B., Saleska, S., Leitold, V., Schietti, J., Longo, M., Alves, L., Camargo, P. and Oliveira, R. | Linking canopy leaf area and light environments with tree size distributions to explain Amazon forest demography [BibTeX] |
2015 | Ecology Letters Vol. 18(7), pp. 636-645 |
article | |
BibTeX:
@article{stark_linking_2015, author = {Stark, SC and Enquist, BJ and Saleska, SR and Leitold, V and Schietti, J and Longo, M and Alves, LF and Camargo, PB and Oliveira, RC}, title = {Linking canopy leaf area and light environments with tree size distributions to explain Amazon forest demography}, journal = {Ecology Letters}, year = {2015}, volume = {18}, number = {7}, pages = {636--645} } |
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Stark, S., Breshears, D., Garcia, E., Law, D., Minor, D., Saleska, S., Swann, A.L., Villegas, J.C., Aragão, L.E. and al. , e. | Toward accounting for ecoclimate teleconnections: intra-and inter-continental consequences of altered energy balance after vegetation change [BibTeX] |
2015 | Landscape Ecology, pp. 1-14 | article | |
BibTeX:
@article{stark_toward_2015, author = {Stark, SC and Breshears, DD and Garcia, ES and Law, DJ and Minor, DM and Saleska, SR and Swann, Abigail LS and Villegas, Juan Camilo and Aragão, Luiz EOC and al., et}, title = {Toward accounting for ecoclimate teleconnections: intra-and inter-continental consequences of altered energy balance after vegetation change}, journal = {Landscape Ecology}, year = {2015}, pages = {1--14} } |
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Staebler, R.M. and Fitzjarrald, D.R. | Observing subcanopy CO2 advection | 2004 | Agricultural and Forest Meteorology Vol. 122(3-4), pp. 139-156 |
article | DOI URL |
Abstract: Underestimation of nocturnal CO2 respiration under calm conditions remains an unsolved problem at many forest flux stations. In this paper, the hypothesis is tested that horizontal mean transport, not previously measured, may account for the missing CO2. A systematic methodology was developed that comprises characterizing the subcanopy motions, determining the appropriate size of the subcanopy network required to make the measurements, developing a method of integrating the measurements in the vertical, and determining the required averaging time. Measurements were performed at the Harvard Forest (Petersham, MA), over 4 years. The appropriate size of the network of wind and CO2 sensors was shown to be on the order of 100 m, ensuring that sensors were generally observing coherent processes on this scale or larger and thus displayed some correlation. Horizontal transport of CO2 at Harvard Forest was found to be restricted to the bottom similar to10 m of the forest. The fraction of the negative buoyancy force in the sum of dynamic driving forces described nights with missing flux problems ("deficit nights") significantly better than the commonly used friction velocity criterion. Including the measured horizontal transport terms did not on average fully account for the observed difference in NEE of 1.2 +/- 0.3 mumol m(-2) s(-1) between deficit and non-deficit nights, but decreased the difference to 0.7 +/- 0.5 mumol m(-2) s(-1). Horizontal transport did account for the difference, to within measurement error, during summer months, but not during spring or fall. Crown Copyright (C) 2003 Published by Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{staebler_observing_2004, author = {Staebler, R. M. and Fitzjarrald, D. R.}, title = {Observing subcanopy CO2 advection}, journal = {Agricultural and Forest Meteorology}, year = {2004}, volume = {122}, number = {3-4}, pages = {139--156}, url = {://WOS:000220547300002}, doi = {https://doi.org/10.1016/j.agrformet.2003.09.011} } |
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Spolador, S., Costa, L. and J., M.H. | Radiação fotossinteticamente ativa em uma floresta de transição cerrado-amazônica [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 301-307 |
article | |
BibTeX:
@article{spolador_radiacao_2006, author = {Spolador, Sanches, L., Costa, M.H., J.}, title = {Radiação fotossinteticamente ativa em uma floresta de transição cerrado-amazônica}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {301--307} } |
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Spanner, G., Gimenez, B., Wright, C., Menezes, V., Newman, B., Collins, A., Jardine, K.J., Negrón-Juárez, R., Lima, A., Rodrigues, J., Chambers, J., Higuchi, N. and Warren, J. | Dry Season Transpiration and Soil Water Dynamics in the Central Amazon | 2022 | Frontiers in Plant Science Vol. 13 |
article | DOI URL |
Abstract: With current observations and future projections of more intense and frequent droughts in the tropics, understanding the impact that extensive dry periods may have on tree and ecosystem-level transpiration and concurrent carbon uptake has become increasingly important. Here, we investigate paired soil and tree water extraction dynamics in an old-growth upland forest in central Amazonia during the 2018 dry season. Tree water use was assessed via radial patterns of sap flow in eight dominant canopy trees, each a different species with a range in diameter, height, and wood density. Paired multi-sensor soil moisture probes used to quantify volumetric water content dynamics and soil water extraction within the upper 100 cm were installed adjacent to six of those trees. To link depth-specific water extraction patterns to root distribution, fine root biomass was assessed through the soil profile to 235 cm. To scale tree water use to the plot level (stand transpiration), basal area was measured for all trees within a 5 m radius around each soil moisture probe. The sensitivity of tree transpiration to reduced precipitation varied by tree, with some increasing and some decreasing in water use during the dry period. Tree-level water use scaled with sapwood area, from 11 to 190 L per day. Stand level water use, based on multiple plots encompassing sap flow and adjacent trees, varied from ∼1.7 to 3.3 mm per day, increasing linearly with plot basal area. Soil water extraction was dependent on root biomass, which was dense at the surface (i.e., 45% in the upper 5 cm) and declined dramatically with depth. As the dry season progressed and the upper soil dried, soil water extraction shifted to deeper levels and model projections suggest that much of the water used during the month-long dry-down could be extracted from the upper 2–3 m. Results indicate variation in rates of soil water extraction across the research area and, temporally, through the soil profile. These results provide key information on whole-tree contributions to transpiration by canopy trees as water availability changes. In addition, information on simultaneous stand level dynamics of soil water extraction that can inform mechanistic models that project tropical forest response to drought. | |||||
BibTeX:
@article{spanner_dry_2022, author = {Spanner, G.C. and Gimenez, B.O. and Wright, C.L. and Menezes, V.S. and Newman, B. and Collins, A.D. and Jardine, K. J. and Negrón-Juárez, R.I. and Lima, A.J.N. and Rodrigues, J.R. and Chambers, J.Q. and Higuchi, N. and Warren, J.M.}, title = {Dry Season Transpiration and Soil Water Dynamics in the Central Amazon}, journal = {Frontiers in Plant Science}, year = {2022}, volume = {13}, url = {https://www.frontiersin.org/articles/10.3389/fpls.2022.825097}, doi = {https://doi.org/10.3389/fpls.2022.825097} } |
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Souza, R. and Ceballos, J. | Análise de desempenho de diferentes sistemas de sondagem sobre rondônia durante o experimento RACCI/LBA [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3a), pp. 129-141 |
article | |
BibTeX:
@article{souza_alise_2006, author = {Souza, R.A.F. and Ceballos, J.C.}, title = {Análise de desempenho de diferentes sistemas de sondagem sobre rondônia durante o experimento RACCI/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3a}, pages = {129--141} } |
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Souza, M., Araújo, M., R.L.C., C., J.C.P., P. and F.M.A., J. | Thermal properties and heat fluxes in soils under forest and pasture, in Marabá, PA, Brazil [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 89-103 |
article | |
BibTeX:
@article{souza_thermal_2006, author = {Souza, Makino, M., Araújo, R.L.C., Cohen, J.C.P., Pinheiro, F.M.A., J.R.S.}, title = {Thermal properties and heat fluxes in soils under forest and pasture, in Marabá, PA, Brazil}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {89--103} } |
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Souza Filho, R., Costa, A., Paulino, M.H., Cohen, E.J. and J.C.P., J. | Variação sazonal do balanço de radiação em uma floresta tropical no nordeste da amazônia [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 318-330 |
article | |
BibTeX:
@article{souza_filho_variacao_2006, author = {Souza Filho, Ribeiro, A., Costa, M.H., Paulino, E.J., Cohen, J.C.P., J.D.C.}, title = {Variação sazonal do balanço de radiação em uma floresta tropical no nordeste da amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {318--330} } |
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Souza Filho Ribeiro, A.C.M.C.J.J. | Mecanismos de controle da variação sazonal da transpiração de uma floresta tropical no nordeste da Amazônia [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 235 - 241 |
article | |
BibTeX:
@article{souza_filho_mecanismos_2005, author = {Souza Filho, Ribeiro, A., Costa, M.H., Cohen J.C.P., J.D.C.}, title = {Mecanismos de controle da variação sazonal da transpiração de uma floresta tropical no nordeste da Amazônia}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {235 -- 241} } |
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Souza, F.F.C., Mathai, P.P., Pauliquevis, T., Balsanelli, E., Pedrosa, F.O., Souza, E.M., Baura, V.A., Monteiro, R.A., Cruz, L.M., Souza, R.A.F., Andreae, M.O., Barbosa, C.G.G., de Angelis, I.H., Sánchez-Parra, B., Pӧhlker, C., Weber, B., Ruff, E., Reis, R.A., Godoi, R.H.M., Sadowsky, M.J. and Huergo, L.F. | Influence of seasonality on the aerosol microbiome of the Amazon rainforest | 2021 | Science of The Total Environment Vol. 760, pp. 144092 |
article | DOI URL |
Abstract: The Amazon rainforest is the world's largest tropical forest, and this biome may be a significant contributor to primary biological aerosol (PBA) emissions on a global scale. These aerosols also play a pivotal role in modulating ecosystem dynamics, dispersing biological material over geographic barriers and influencing climate through radiation absorption, light scattering, or acting as cloud condensation nuclei. Despite their importance, there are limited studies investigating the effect of environmental variables on the bioaerosol composition in the Amazon rainforest. Here we present a 16S rRNA gene-based amplicon sequencing approach to investigate the bacterial microbiome in aerosols of the Amazon rainforest during distinct seasons and at different heights above the ground. Our data revealed that seasonal changes in temperature, relative humidity, and precipitation are the primary drivers of compositional changes in the Amazon rainforest aerosol microbiome. Interestingly, no significant differences were observed in the bacterial community composition of aerosols collected at ground and canopy levels. The core airborne bacterial families present in Amazon aerosol were Enterobacteriaceae, Beijerinckiaceae, Polyangiaceae, Bacillaceae and Ktedonobacteraceae. By correlating the bacterial taxa identified in the aerosol with literature data, we speculate that the phyllosphere may be one possible source of airborne bacteria in the Amazon rainforest. Results of this study indicate that the aerosol microbiota of the Amazon Rainforest are fairly diverse and principally impacted by seasonal changes in temperature and humidity. | |||||
BibTeX:
@article{souza_influence_2021, author = {Souza, Felipe F. C. and Mathai, Prince P. and Pauliquevis, Theotonio and Balsanelli, Eduardo and Pedrosa, Fabio O. and Souza, Emanuel M. and Baura, Valter A. and Monteiro, Rose A. and Cruz, Leonardo M. and Souza, Rodrigo A. F. and Andreae, Meinrat O. and Barbosa, Cybelli G. G. and de Angelis, Isabella Hrabe and Sánchez-Parra, Beatriz and Pӧhlker, Christopher and Weber, Bettina and Ruff, Emil and Reis, Rodrigo A. and Godoi, Ricardo H. M. and Sadowsky, Michael J. and Huergo, Luciano F.}, title = {Influence of seasonality on the aerosol microbiome of the Amazon rainforest}, journal = {Science of The Total Environment}, year = {2021}, volume = {760}, pages = {144092}, url = {https://www.sciencedirect.com/science/article/pii/S0048969720376233}, doi = {https://doi.org/10.1016/j.scitotenv.2020.144092} } |
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Souza, Rissi, D. V., Pedrosa, F. O., Souza, E. M., Baura, V. A., Monteiro, R. A., Balsanelli, E., Cruz, L. M., Souza, R. A. F., Andreae, M. O., Reis, R. A., Godoi, R. H. M., Huergo, L. F., F. F. C. | Uncovering prokaryotic biodiversity within aerosols of the pristine Amazon forest [BibTeX] |
2019 | Science of the Total Environment. Vol. 688, pp. 83-86 |
article | DOI |
BibTeX:
@article{souza_uncovering_2019, author = {Souza, Rissi, D. V., Pedrosa, F. O., Souza, E. M., Baura, V. A., Monteiro, R. A., Balsanelli, E., Cruz, L. M., Souza, R. A. F., Andreae, M. O., Reis, R. A., Godoi, R. H. M., Huergo, L. F., F. F. C.}, title = {Uncovering prokaryotic biodiversity within aerosols of the pristine Amazon forest}, journal = {Science of the Total Environment.}, year = {2019}, volume = {688}, pages = {83--86}, doi = {https://doi.org/10.1016/j.scitotenv.2019.06.218} } |
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Souza, E.P., Renno, N.O. and Dias, M. | Convective circulations induced by surface heterogeneities | 2000 | Journal of the Atmospheric Sciences Vol. 57(17), pp. 2915-2922 |
article | DOI URL |
Abstract: A simple theory for convective circulations induced by surface heterogeneities is proposed. The theory is based on the thermodynamics of heat engines and provides a simple physical explanation for the general characteristics of circulations forced by surface inhomogeneities in sloping terrains. In particular, the theory is applied to a mesoscale circulation induced by deforestation. It predicts that the intensity of the mesoscale convective circulation forced by deforestation depends on the difference of the near-surface nonadiabatic temperature and humidity between the forest and cleared regions and on the depth of the convective boundary layer. The theory was successfully tested against observations made during a field experiment in the Amazon forest and a nearby clearing. | |||||
BibTeX:
@article{souza_convective_2000, author = {Souza, E. P. and Renno, N. O. and Dias, Mafs}, title = {Convective circulations induced by surface heterogeneities}, journal = {Journal of the Atmospheric Sciences}, year = {2000}, volume = {57}, number = {17}, pages = {2915--2922}, url = {://WOS:000089229100009}, doi = {https://doi.org/10.1175/1520-0469(2000)057%3C2915:ccibsh%3E2.0.co;2} } |
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Souza, E. and Rocha, E. | Diurnal Variation of Rainfall In Bragança-Pa (Eastern Amazon) During Rainy Season: Mean Characteristics And Extreme Events [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 142-152 |
article | |
BibTeX:
@article{souza_diurnal_2006, author = {Souza, E.B. and Rocha, E.J.P.}, title = {Diurnal Variation of Rainfall In Bragança-Pa (Eastern Amazon) During Rainy Season: Mean Characteristics And Extreme Events}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {142--152} } |
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Souza, E.B., Lopes, M.N.G., Rocha, E.J.P., Souza, J.R.S., Cunha, A.C., Ramos da Silva, R., Ferreira, D.B.S., Santos, D.M., Carmo, A.M.C., Souza, J.R.A., Guimarães, P.L., Mota, M.A., Makino, M., Souza, A.M.L., Mota, G.V., Kuhn, P.A.F., Souza, P.F.S. and Vitorino, M.I. | Precipitação Sazonal Sobre a Amazônia Oriental no Período Chuvoso: Observaçoões e Simulações Regionais com o REGCM3 [BibTeX] |
2009 | Revista Brasileira de Meteorologia Vol. 24, pp. 111-124 |
article | |
BibTeX:
@article{souza_precipitacao_2009, author = {Souza, E. B. and Lopes, M. N. G. and Rocha, E. J. P. and Souza, J. R. S. and Cunha, A. C. and Ramos da Silva, R. and Ferreira, D. B. S. and Santos, D. M. and Carmo, A. M. C. and Souza, J. R. A. and Guimarães, P. L. and Mota, M. A. and Makino, M. and Souza, A. M. L. and Mota, G. V. and Kuhn, P. A. F. and Souza, P. F. S. and Vitorino, M. I.}, title = {Precipitação Sazonal Sobre a Amazônia Oriental no Período Chuvoso: Observaçoões e Simulações Regionais com o REGCM3}, journal = {Revista Brasileira de Meteorologia}, year = {2009}, volume = {24}, pages = {111--124} } |
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Souza Kayano, M., Tota, J., Pezzi, L. and Fisch G.F. & Nobre, C.E. | On the influence of the El Niño, La Niña and Atlantic dipole pattern on the Amazonian rainfall during 1960-1998 [BibTeX] |
2000 | Acta Amazonica Vol. 30, pp. 305-318 |
article | |
BibTeX:
@article{souza_influence_2000, author = {Souza, Kayano, M.; Tota, J.; Pezzi, L.P.; Fisch, G.F. & Nobre, C.A., E.B.}, title = {On the influence of the El Niño, La Niña and Atlantic dipole pattern on the Amazonian rainfall during 1960-1998}, journal = {Acta Amazonica}, year = {2000}, volume = {30}, pages = {305--318} } |
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Souza, C.M.d., Dias-Júnior, C.Q., Tóta, J. and Sá, L.D.d.A. | An empirical-analytical model of the vertical wind speed profile above and within an Amazon forest site [BibTeX] |
2016 | Meteorological Applications Vol. 23, pp. 158-164 |
article | DOI |
BibTeX:
@article{souza_empirical-analytical_2016, author = {Souza, Cledenilson Mendonça de and Dias-Júnior, Cléo Quaresma and Tóta, Júlio and Sá, Leonardo Deane de Abreu}, title = {An empirical-analytical model of the vertical wind speed profile above and within an Amazon forest site}, journal = {Meteorological Applications}, year = {2016}, volume = {23}, pages = {158--164}, doi = {https://doi.org/10.1002/met.1543} } |
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Souza Jr., C., Roberts, D.A. and Monteiro, A. | Multitemporal analysis of degraded forests in the southern Brazilian Amazon | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: In this study, statistical multitemporal analysis was applied to evaluate the capability of reflectance, vegetation indices [ normalized difference vegetation index (NDVI) and soil adjusted vegetation index (SAVI)], normalized difference infrared indices (NDII5 and NDII7), and fraction images, derived from spectral mixture analysis (SMA), to distinguish intact forest from four classes of degraded forests: nonmechanized logging, managed logging, conventional logging, and logged and burned. For this purpose, a robust time series dataset of Landsat Thematic Mapper 5/Enhanced Thematic Mapper (TM/ ETM+) images was used in conjunction with forest inventory transects and data on disturbance history. The study area is located near two important sawmill centers - Sinop and Claudia, in Mato Grosso State - in the southern Brazilian Amazon. Most of the remote sensing measures tested to distinguish intact forest from degraded forests showed statistically significant changes. Fraction images, particularly green vegetation (GV) and nonphotosynthetic vegetation (NPV), were the most effective means tested for identifying conventional logging and logged and burned forest in the region. The GV change, detected from intact forest to conventional logging and logged and burned forest classes, persists no more than 1 yr, but the NPV change is still significantly different for up to 2 yr. In the second and third years following a degradation event, a significant regeneration change signal was observed in reflectance and fraction images, which can be useful for identifying these types of forest disturbances in areas where optical satellite images cannot be acquired every year. | |||||
BibTeX:
@article{souza_multitemporal_2005, author = {Souza, Jr., C.M. and Roberts, Dar A. and Monteiro, A.L.}, title = {Multitemporal analysis of degraded forests in the southern Brazilian Amazon}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241357600001} } |
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Souza, C.M., Roberts, D.A. and Cochrane, M.A. | Combining spectral and spatial information to map canopy damage from selective logging and forest fires | 2005 | Remote Sensing of Environment Vol. 98(2-3), pp. 329-343 |
article | DOI URL |
Abstract: We propose a new spectral index, the Normalized Difference Fraction Index (NDFI), for enhanced detection of forest canopy damage caused by selective logging activities and associated forest fires. The NDFI synthesizes information from several component fraction images derived from spectral mixture models. Interpretation of the NDFI data is facilitated by 4 contextual classification algorithm (CCA) that enables accurate mapping of logging and fire-derived canopy damages. The CCA utilizes detected log landings, which are the spatial signature of selective logging, as starting locations for searching the NDFI image for canopy damage. This process separates canopy changes due to logging and associated forest fires from those caused by other natural disturbances. These methods were tested in the Sinop region, in the Southern Brazilian Amazon. Forest transect inventories, conducted along a gradient of degraded forests, were used to evaluated the performance of the NDFI. The NDFI was more sensitive to canopy damage than any individual fraction and is shown to have the potential for further sub-classification of degradation levels in forest environments. Map accuracy of forest canopy damage using the CCA classifier, assessed with aerial videography images, was 94%. The proposed NDFI-CCA classifier approach can be fully automated and, therefore, holds great promise as a forest monitoring tool in tropical forests. (C) 2005 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{souza_combining_2005, author = {Souza, C. M. and Roberts, D. A. and Cochrane, M. A.}, title = {Combining spectral and spatial information to map canopy damage from selective logging and forest fires}, journal = {Remote Sensing of Environment}, year = {2005}, volume = {98}, number = {2-3}, pages = {329--343}, url = {://WOS:000232742900013}, doi = {https://doi.org/10.1016/j.rse.2005.07.013} } |
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Souza, C.M. and Roberts, D. | Mapping forest degradation in the Amazon region with Ikonos images [BibTeX] |
2005 | International Journal of Remote Sensing Vol. 26(3), pp. 425-429 |
article | DOI URL |
BibTeX:
@article{souza_mapping_2005, author = {Souza, C. M. and Roberts, D.}, title = {Mapping forest degradation in the Amazon region with Ikonos images}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {3}, pages = {425--429}, url = {://WOS:000226835700001}, doi = {https://doi.org/10.1080/0143116031000101620} } |
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Souza, C., Sá, L. and Tóta, J. | Filtragem de momentum por escala pelo dossel da floresta Amazônica [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 61-64 |
article | |
BibTeX:
@article{souza_filtragem_2009, author = {Souza, Cledenilson and Sá, Leonardo and Tóta, Julio}, title = {Filtragem de momentum por escala pelo dossel da floresta Amazônica}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {61--64} } |
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Souza, C., Firestone, L., Silva, L.M. and Roberts, D. | Mapping forest degradation in the Eastern Amazon from SPOT 4 through spectral mixture models | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 494-506 |
article | DOI URL |
Abstract: In this paper, we present a methodology to map classes of degraded forest in the Eastern Amazon. Forest degradation field data, available in the literature, and I-m resolution IKONOS image were linked with fraction images (vegetation, nonphotosynthetic vegetation (NPV), soil and shade) derived from spectral mixture models applied to a Satellite Pour L'observation de la Terre (SPOT) 4 multispectral image. The forest degradation map was produced in two steps. First, we investigated the relationship between ground (i.e., field and IKONOS data) and satellite scales by analyzing statistics and performing visual analyses of the field classes in terms of fraction values. This procedure allowed us to define four classes of forest at the SPOT 4 image scale, which included: intact forest; logged forest (recent and older logged forests in the field); degraded forest (heavily burned, heavily logged and burned forests in the field); and regeneration (old heavily logged and old heavily burned forest in the field). Next, we used a decision tree classifier (DTC) to define a set of rules to separate the forest classes using the fraction images. We classified 35% of the forest area (2097.3 km(2)) as intact forest. Logged forest accounted for 56% of the forest area and 9% of the forest area was classified as degraded forest. The resultant forest degradation map showed good agreement (86% overall accuracy) with areas of degraded forest visually interpreted from two IKONOS images. In addition, high correlation (R-2 = 0.97) was observed between the total live aboveground biomass of degraded forest classes (defined at the field scale) and the NPV fraction image. The NPV fraction also improved our ability to mapping of old selectively logged forests. (C) 2003 Published by Elsevier Inc. | |||||
BibTeX:
@article{souza_mapping_2003, author = {Souza, C. and Firestone, L. and Silva, L. M. and Roberts, D.}, title = {Mapping forest degradation in the Eastern Amazon from SPOT 4 through spectral mixture models}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {494--506}, url = {://WOS:000186827400009}, doi = {https://doi.org/10.1016/j.rse.2002.08.002} } |
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Souza, C. and Barreto, P. | An alternative approach for detecting and monitoring selectively logged forests in the Amazon | 2000 | International Journal of Remote Sensing Vol. 21(1), pp. 173-179 |
article | DOI URL |
Abstract: A methodology is presented for estimating the area affected by selective logging in Amazonia's terra firme forests. Areas of land cleared for temporarily storing logs in the forest (log landings) were detected within soil fraction images derived from linear mixture models of forested areas. Based on field data, a 180 m timber extraction radius was assumed for all log landings. The extraction area calculated for detected log landings provides an estimate of the area potentially affected by logging. The resultant image classifications revealed excellent agreement with field data. This methodology can be a powerful tool for the monitoring and control of logging in the Amazon. | |||||
BibTeX:
@article{souza_alternative_2000, author = {Souza, C. and Barreto, P.}, title = {An alternative approach for detecting and monitoring selectively logged forests in the Amazon}, journal = {International Journal of Remote Sensing}, year = {2000}, volume = {21}, number = {1}, pages = {173--179}, url = {://WOS:000084681600013}, doi = {https://doi.org/10.1080/014311600211064} } |
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Sousa Moura, J.M., Martens, C.S., Moreira, M.Z., Lima, R.L., Goncalves Sampaio, I.C., Mendlovitz, H.P. and Menton, M.C. | Spatial and seasonal variations in the stable carbon isotopic composition of methane in stream sediments of eastern Amazonia | 2008 | Tellus Series B-Chemical and Physical Meteorology Vol. 60(1), pp. 21-31 |
article | DOI URL |
Abstract: The stable carbon isotopic composition of methane (delta(13)C-CH(4)) gas bubbles formed in the sediments of three Amazonian streams was determined over a 5-yr period. The study sites were two 'varzea' floodplain (Acu and Maica) and one 'terra-firme' (Jamaraqua) streams. The delta(13)C of sedimentary organic matter (SOM) from the surrounding vegetation and bottom sediments were also determined. The mean delta(13)C value of SOM was lower in the terra-firme (-29.6 parts per thousand) than in the varzea stream (-23.8 parts per thousand) as a result of less C(4) plant deposition in the former. The delta(13)C-CH(4) values varied systematically both seasonally and spatially among the sites during all 5 yr of the study, in association with changes during hydrologic cycle. Overall, the variation in values of delta(13)C-CH(4) during the high water phase covered a narrower range of values, -63 to -56 parts per thousand. Contrastively, during the low water phase the delta(13)C-CH(4) values for varzea and terra-firme streams are different and are in direct opposition. At this phase, the delta(13)C-CH(4) at terra-firme stream is at least 20 parts per thousand depleted of (13)C compared to varzea streams. Changes in organic matter sources, water levels and associated microbial degradation processes control the observed seasonal and spatial variations in net stable carbon isotopic composition of methane. | |||||
BibTeX:
@article{sousa_moura_spatial_2008, author = {Sousa Moura, Jose Mauro and Martens, Christopher S. and Moreira, Marcelo Zacharias and Lima, Risonaldo Leal and Goncalves Sampaio, Irene Cibelle and Mendlovitz, Howard P. and Menton, Mary C.}, title = {Spatial and seasonal variations in the stable carbon isotopic composition of methane in stream sediments of eastern Amazonia}, journal = {Tellus Series B-Chemical and Physical Meteorology}, year = {2008}, volume = {60}, number = {1}, pages = {21--31}, url = {://WOS:000252331400003}, doi = {https://doi.org/10.1111/j.1600-0889.2007.00322.x} } |
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Sousa, E.d.S., Salimon, C.I., Figueiredo, R.d.O. and Krusche, A.V. | Dissolved carbon in an urban area of a river in the Brazilian Amazon | 2011 | Biogeochemistry Vol. 105(1-3), pp. 159-170 |
article | DOI URL |
Abstract: The main objective of this study was to evaluate dissolved organic and inorganic carbon dynamics along upstream and downstream reaches of the Acre River draining the city of Rio Branco, in the state of Acre, Brazil. Dissolved organic carbon (DOC) concentrations in the Acre River were significantly higher during the wet season, ranging from 385 +/- A 160 to 430 +/- A 131 mu M among the stations, with no difference in upstream and downstream concentrations. Dissolved inorganic carbon (DIC) showed an inverse pattern, with higher concentrations in the dry season, ranging from 816 +/- A 215 to 998 +/- A 754 mu M among the stations, as well as no difference in upstream and downstream DIC concentrations. Bicarbonate was the dominant DIC fraction and was mainly observed during the dry season. Due to lower pH values during the wet season, CO(2) partial pressure (pCO(2)) in the Acre River was higher in the wet season, with values ranging from 4,567 +/- A 1,813 to 4,893 +/- A 837 ppm among the stations. Our results indicate that, although the Acre River drains a large city with significant sewage disposal into the river, seasonal hydrological processes are the main driver of dissolved carbon dynamics, even in the downstream study reach directly influenced by urbanization. | |||||
BibTeX:
@article{sousa_dissolved_2011, author = {Sousa, Eliete dos Santos and Salimon, Cleber Ibraim and Figueiredo, Ricardo de Oliveira and Krusche, Alex Vladimir}, title = {Dissolved carbon in an urban area of a river in the Brazilian Amazon}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {159--170}, url = {://WOS:000294501100012}, doi = {https://doi.org/10.1007/s10533-011-9613-z} } |
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Sousa, A.M.L.d., Vitorino, M.I., Castro, N.M.d.R., Botelho, M.d.N. and Souza, P.J.O.P.d. | Evapotranspiração a partir de Sensoriamento Remoto para Assimilação no Modelo Swat no Leste da Amazônia [BibTeX] |
2015 | Floresta Ambient. Vol. 22(4), pp. 456-464 |
article | DOI |
BibTeX:
@article{sousa_evapotranspiracao_2015, author = {Sousa, Adriano Marlison Leão de and Vitorino, Maria Isabel and Castro, Nilza Maria dos Reis and Botelho, Marcel do Nascimento and Souza, Paulo Jorge Oliveira Ponte de}, title = {Evapotranspiração a partir de Sensoriamento Remoto para Assimilação no Modelo Swat no Leste da Amazônia}, journal = {Floresta Ambient.}, year = {2015}, volume = {22}, number = {4}, pages = {456--464}, doi = {https://doi.org/10.1590/2179-8087.083814} } |
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Sousa, A.M.L., Rocha, E.J.P. and Cohen, J.C.P. | Estudo Observacional da Dinâmica da Formação e Evolução da Camada Limite Planetária nos Ecossistemas de Manguezal e Floresta Natural Durante o Período Chuvoso de 2002 [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21, pp. 12-20 |
article | |
BibTeX:
@article{sousa_estudo_2006, author = {Sousa, A. M. L. and Rocha, E. J. P. and Cohen, J. C. P.}, title = {Estudo Observacional da Dinâmica da Formação e Evolução da Camada Limite Planetária nos Ecossistemas de Manguezal e Floresta Natural Durante o Período Chuvoso de 2002}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, pages = {12--20} } |
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Sousa, C., C.R.J., R. and E.J.P., A. | Episode of low level jets in the north and northeast coast of State of Para: a case study of 2002 april 21st to 22nd. [BibTeX] |
2008 | Revista Brasileira de Meteorologia Vol. 23(3), pp. 334-340 |
article | |
BibTeX:
@article{sousa_episode_2008, author = {Sousa, Campos, C.R.J., Rocha, E.J.P., A.M.L.}, title = {Episode of low level jets in the north and northeast coast of State of Para: a case study of 2002 april 21st to 22nd.}, journal = {Revista Brasileira de Meteorologia}, year = {2008}, volume = {23}, number = {3}, pages = {334--340}, note = {Section: 3} } |
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Sousa, C., C.R.J., R. and E.J.P., A. | No litoral norte e nordeste do estado do Pará durante os períodos chuvoso (2002) e seco (2003) [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(2), pp. 170-179 |
article | |
BibTeX:
@article{sousa_no_2006, author = {Sousa, Campos, C.R.J., Rocha, E.J.P., A.M.L.}, title = {No litoral norte e nordeste do estado do Pará durante os períodos chuvoso (2002) e seco (2003)}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {2}, pages = {170--179} } |
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Sousa, R., E.J.P., C. and J.C.P., A. | Desenvolvimento da camada limite planetária nos ecossistemas de mangue e floresta [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 224-232 |
article | |
BibTeX:
@article{sousa_desenvolvimento_2006, author = {Sousa, Rocha, E.J.P., Cohen, J.C.P., A.M.L.}, title = {Desenvolvimento da camada limite planetária nos ecossistemas de mangue e floresta}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {224--232} } |
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Sotta, E.D., Veldkamp, E., Schwendenmann, L., Guimaraes, B.R., Paixao, R.K., Ruivo, M.D.L.P., Lola Da Costa, A.C. and Meir, P. | Effects of an induced drought on soil carbon dioxide (CO(2)) efflux and soil CO(2) production in an Eastern Amazonian rainforest, Brazil | 2007 | Global Change Biology Vol. 13(10), pp. 2218-2229 |
article | DOI URL |
Abstract: In the next few decades, climate of the Amazon basin is expected to change, as a result of deforestation and rising temperatures, which may lead to feedback mechanisms in carbon (C) cycling that are presently unknown. Here, we report how a throughfall exclusion (TFE) experiment affected soil carbon dioxide (CO(2)) production in a deeply weathered sandy Oxisol of Caxiuana (Eastern Amazon). Over the course of 2 years, we measured soil CO(2) efflux and soil CO(2) concentrations, soil temperature and moisture in pits down to 3 m depth. Over a period of 2 years, TFE reduced on average soil CO(2) efflux from 4.3 +/- 0.1 mu mol CO(2) m(-2) s(-1) (control) to 3.2 +/- 0.1 mu mol CO(2) m(-2) s(-1) (TFE). The contribution of the subsoil (below 0.5 m depth) to the total soil CO(2) production was higher in the TFE plot (28%) compared with the control plot (17%), and it did not differ between years. We distinguished three phases of drying after the TFE was started. The first phase was characterized by a translocation of water uptake (and accompanying root activity) to deeper layers and not enough water stress to affect microbial activity and/or total root respiration. During the second phase a reduction in total soil CO(2) efflux in the TFE plot was related to a reduction of soil and litter decomposers activity. The third phase of drying, characterized by a continuing decrease in soil CO(2) production was dominated by a water stress-induced decrease in total root respiration. Our results contrast to results of a drought experiment on clay Oxisols, which may be related to differences in soil water retention characteristics and depth of rooting zone. These results show that large differences exist in drought sensitivity among Amazonian forest ecosystems, which primarily seem to be affected by the combined effects of texture (affecting water holding capacity) and depth of rooting zone. | |||||
BibTeX:
@article{sotta_effects_2007, author = {Sotta, Eleneide Doff and Veldkamp, Edzo and Schwendenmann, Luitgard and Guimaraes, Brenda Rocha and Paixao, Rosiene Keila and Ruivo, Maria De Lourdes P. and Lola Da Costa, Antonio Carlos and Meir, Patrick}, title = {Effects of an induced drought on soil carbon dioxide (CO(2)) efflux and soil CO(2) production in an Eastern Amazonian rainforest, Brazil}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {10}, pages = {2218--2229}, url = {://WOS:000249991600014}, doi = {https://doi.org/10.1111/j.1365-2486.2007.01416.x} } |
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Sotta, E.D., Veldkamp, E., Guimaraes, B.R., Paixao, R.K., Ruivo, M.L.P. and Almeida, S.S. | Landscape and climatic controls on spatial and temporal variation in soil CO(2) efflux in an Eastern Amazonian Rainforest, Caxiuana, Brazil | 2006 | Forest Ecology and Management Vol. 237(1-3), pp. 57-64 |
article | DOI URL |
Abstract: Quantification of temporal and spatial variation of soil CO(2) emissions is essential for an accurate interpretation of tower-based measurements of net ecosystem exchange. Here, we measured in the old-growth forest of Caxiuana, Eastern Amazonia soil CO(2) efflux and its environmental controls from two Oxisol sites with contrasting soil texture and at different landscape positions. Average CO(2) efflux was 21% higher for sand (3.93 +/- 0.06 mu mol CO(2) m(-2) s(-1)) than for the clay (3.08 +/- 0.07 mu mol CO(2), m(-2) s(-1)). No difference was detected for soil temperature between sites, while soil water content in sandy soil (23.2 +/- 0.33%) was much lower than the clay soil (34.5 +/- 0.98%), for the 2-year period. Soil CO(2) efflux did not differ between dry and wet season, but we detected a significant interaction between season and topographic position. The variation caused by topography was in the same order of magnitude as temporal variation. Mean contribution of the litter layer to the CO(2) efflux rates was 20% and varied from 25% during the wet season to close to 0% during the dry season. The relation between soil water content and soil CO(2) efflux showed an optimum for both soil textures but the shape and optimum of the curves were different. The results of our study illustrate that soil moisture is an important driver of temporal variations in soil CO(2) efflux in this old-growth forest. When extrapolating soil CO(2) efflux to larger areas, the significant influences of soil texture, litter, and the interaction of topographical position and time illustrate that it is necessary to include some of the complexity of landscapes. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{sotta_landscape_2006, author = {Sotta, E. D. and Veldkamp, E. and Guimaraes, B. R. and Paixao, R. K. and Ruivo, M. L. P. and Almeida, S. S.}, title = {Landscape and climatic controls on spatial and temporal variation in soil CO(2) efflux in an Eastern Amazonian Rainforest, Caxiuana, Brazil}, journal = {Forest Ecology and Management}, year = {2006}, volume = {237}, number = {1-3}, pages = {57--64}, url = {://WOS:000243230900006}, doi = {https://doi.org/10.1016/j.foreco.2006.09.027} } |
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Sotta, E.D., Meir, P., Malhi, Y., Nobre, A.D., Hodnett, M. and Grace, J. | Soil CO2 efflux in a tropical forest in the central Amazon | 2004 | Global Change Biology Vol. 10(5), pp. 601-617 |
article | DOI URL |
Abstract: This study investigated the spatial and temporal variation in soil carbon dioxide (CO2) efflux and its relationship with soil temperature, soil moisture and rainfall in a forest near Manaus, Amazonas, Brazil. The mean rate of efflux was 6.45+/-0.25 SE mumol CO2 m(-2)s(-1) at 25.6+/-0.22 SEdegreesC (5 cm depth) ranging from 4.35 to 9.76 mumol CO2 m(-2)s(-1); diel changes in efflux were correlated with soil temperature (r(2)=0.60). However, the efflux response to the diel cycle in temperature was not always a clear exponential function. During period of low soil water content, temperature in deeper layers had a better relationship with CO2 efflux than with the temperature nearer the soil surface. Soil water content may limit CO2 production during the drying-down period that appeared to be an important factor controlling the efflux rate (r(2)=0.39). On the other hand, during the rewetting period microbial activity may be the main controlling factor, which may quickly induce very high rates of efflux. The CO2 flux chamber was adapted to mimic the effects of rainfall on soil CO2 efflux and the results showed that efflux rates reduced 30% immediately after a rainfall event. Measurements of the CO2 concentration gradient in the soil profile showed a buildup in the concentration of CO2 after rain on the top soil. This higher CO2 concentration developed shortly after rainfall when the soil pores in the upper layers were filled with water, which created a barrier for gas exchange between the soil and the atmosphere. | |||||
BibTeX:
@article{sotta_soil_2004, author = {Sotta, E. D. and Meir, P. and Malhi, Y. and Nobre, A. D. and Hodnett, M. and Grace, J.}, title = {Soil CO2 efflux in a tropical forest in the central Amazon}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {601--617}, url = {://WOS:000221421600006}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00761.x} } |
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Sotta, E.D., Corre, M.D. and Veldkamp, E. | Differing N status and N retention processes of soils under old-growth lowland forest in Eastern Amazonia, Caxiuana, Brazil | 2008 | Soil Biology & Biochemistry Vol. 40(3), pp. 740-750 |
article | DOI URL |
Abstract: Indirect evidence of the nitrogen (N) status of tropical forests strongly suggests that in heavily weathered soils under old-growth lowland tropical forests nitrogen is in relative excess. However, within the lowland forests of the Amazon basin, there is substantial evidence that soil texture influences soil NH(4)(+) and NO(3)(-) concentrations and hence possibly N availability and retention in the soil. Here, we evaluate the soil N status of two heavily weathered soils which contrast in texture (sandy versus clay Oxisol). Using (15)N pool dilution, we quantified gross rates of soil N cycling and retention. We also measured the delta(15)N signatures from the litter layer down to 50-cm depth mineral soil and calculated the overall (15)N enrichment factor (epsilon) for each soil type. The clay soil showed high gross N mineralization and nitrification rates and a high overall (15)N enrichment factor, signifying high N losses. The sandy soil had low gross rates of N cycling and (15)N enrichment factor, manifesting a conservative soil N cycling. Faster turnover rates of NH(4)(+) compared to NO(3)(-) indicated that NH(4)(+) cycles faster through microorganisms than NO(3)(-), possibly contributing to better retention of NH(4)(+) than NO(3)(-). However this was opposite to abiotic retention processes, which showed higher conversion of NO(3)(-) to the organic N pool than NH(4)(+). Our combined results suggest that clay Oxisol in Amazonian forest have higher N availability than sandy Oxisol, which will have important consequences for changes in soil N cycling and losses when projected increase in anthropogenic N deposition will occur. (c) 2007 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{sotta_differing_2008, author = {Sotta, Elenelde Doff and Corre, Marife D. and Veldkamp, Edzo}, title = {Differing N status and N retention processes of soils under old-growth lowland forest in Eastern Amazonia, Caxiuana, Brazil}, journal = {Soil Biology & Biochemistry}, year = {2008}, volume = {40}, number = {3}, pages = {740--750}, url = {://WOS:000253000800017}, doi = {https://doi.org/10.1016/j.soilbio.2007.10.009} } |
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Soto-Garcia, L.L., Andreae, M.O., Andreae, T.W., Artaxo, P., Maenhaut, W., Kirchstetter, T., Novakov, T., Chow, J.C. and Mayol-Bracero, O.L. | Evaluation of the carbon content of aerosols from the burning of biomass in the Brazilian Amazon using thermal, optical and thermal-optical analysis methods | 2011 | Atmospheric Chemistry and Physics Vol. 11(9), pp. 4425-4444 |
article | DOI URL |
Abstract: Aerosol samples were collected at a pasture site in the Amazon Basin as part of the project LBA-SMOCC-2002 (Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Smoke Aerosols, Clouds, Rainfall and Climate: Aerosols from Biomass Burning Perturb Global and Regional Climate). Sampling was conducted during the late dry season, when the aerosol composition was dominated by biomass burning emissions, especially in the submicron fraction. A 13-stage Dekati low-pressure impactor (DLPI) was used to collect particles with nominal aerodynamic diameters (D(p)) ranging from 0.03 to 0.10 mu m. Gravimetric analyses of the DLPI substrates and filters were performed to obtain aerosol mass concentrations. The concentrations of total, apparent elemental, and organic carbon (TC, EC(a), and OC) were determined using thermal and thermal-optical analysis (TOA) methods. A light transmission method (LTM) was used to determine the concentration of equivalent black carbon (BC(e)) or the absorbing fraction at 880 nm for the size-resolved samples. During the dry period, due to the pervasive presence of fires in the region upwind of the sampling site, concentrations of fine aerosols (D(p) textless 2.5 mu m: average 59.8 mu g m(-3)) were higher than coarse aerosols (D(p) textgreater 2.5 mu m: 4.1 mu g m(-3)). Carbonaceous matter, estimated as the sum of the particulate organic matter (i.e., OC x 1.8) plus BC(e), comprised more than 90% to the total aerosol mass. Concentrations of EC(a) (estimated by thermal analysis with a correction for charring) and BC(e) (estimated by LTM) averaged 5.2 +/- 1.3 and 3.1 +/- 0.8 mu g m(-3), respectively. The determination of EC was improved by extracting water-soluble organic material from the samples, which reduced the average light absorption Angstrom exponent of particles in the size range of 0.1 to 1.0 mu m from textgreater2.0 to approximately 1.2. The size-resolved BC(e) measured by the LTM showed a clear maximum between 0.4 and 0.6 mu m in diameter. The concentrations of OC and BC(e) varied diurnally during the dry period, and this variation is related to diurnal changes in boundary layer thickness and in fire frequency. | |||||
BibTeX:
@article{soto-garcia_evaluation_2011, author = {Soto-Garcia, L. L. and Andreae, M. O. and Andreae, T. W. and Artaxo, P. and Maenhaut, W. and Kirchstetter, T. and Novakov, T. and Chow, J. C. and Mayol-Bracero, O. L.}, title = {Evaluation of the carbon content of aerosols from the burning of biomass in the Brazilian Amazon using thermal, optical and thermal-optical analysis methods}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, number = {9}, pages = {4425--4444}, url = {://WOS:000290618600027}, doi = {https://doi.org/10.5194/acp-11-4425-2011} } |
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Sorribas, R.C.D., Melack, J.M., Bravo, J.M., Jones, C., Carvalho, L., Beighley, E., Forsberg, B., Costa Marcos Heil, M.V. and Paiva | Projections of climate change effects on discharge and inundation in the Amazon basin [BibTeX] |
2016 | Climatic Change Vol. 136, pp. 555-570 |
article | |
BibTeX:
@article{sorribas_projections_2016, author = {Sorribas, Rodrigo C. D. ; Melack, John M. ; Bravo, Juan Martin ; Jones, Charles ; Carvalho, Leila ; Beighley, Edward ; Forsberg, Bruce ; Costa, Marcos Heil, Mino Viana ; Paiva}, title = {Projections of climate change effects on discharge and inundation in the Amazon basin}, journal = {Climatic Change}, year = {2016}, volume = {136}, pages = {555--570} } |
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Sommer, R., Sa, T.D.D., Vielhauer, K., de Araujo, A.C., Folster, H. and Vlek, P.L.G. | Transpiration and canopy conductance of secondary vegetation in the eastern Amazon | 2002 | Agricultural and Forest Meteorology Vol. 112(2), pp. 103-121 |
article | DOI URL |
Abstract: Secondary woody vegetation in the Brazilian Amazon accounts for about 30% of the cleared area in this region, which exceeds 100,000km(2). Despite the relative predominance of secondary vegetation, the hydrological and climatic properties of these areas are not well documented. In an effort to address this, the evapotranspiration (E) of a 3.5-year-old secondary vegetation in the eastern Amazon of Brazil was measured over 1 year, The annual evapotranspiration according to the Bowen ratio energy balance (BREB) amounted to 1421 mm, which is equal to rates quoted for tropical primary forests. The secondary vegetation returned 73% of the annual rainfall (1954 mm) to the atmosphere, Evapotranspiration required 73% of the net-radiation (R-n) energy; this function remained fairly constant over the whole year. In order to estimate evapotranspiration with the Penman-Monteith (PM) method, the canopy conductance (g(c)) was determined using the BREB results. The monthly mean daily g, varied between 14 and 22 mm s(-1) in the rainy season and the transitional period (January-August), and reached a minimum of 7 mm s(-1) in the dry season in October. The hourly as well as daily mean canopy conductance were approximated by a multiple linear regression analysis incorporating hourly and daily averages of R-n and vapour pressure deficit, respectively. In addition, the Jarvis-type model, which is based on a set of environmental control functions, was applied to predict hourly g(c). The multiple linear regression and the non-linear optimisation (Jarvis-type model) were equally suitable for g(c) prediction. The optimised environmental control functions were comparable to those predicted elsewhere for Amazonian primary forests. This underlines the similarity of secondary and primary forests with respect to hydrological characteristics as well as energy turnover. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{sommer_transpiration_2002, author = {Sommer, R. and Sa, T. D. D. and Vielhauer, K. and de Araujo, A. C. and Folster, H. and Vlek, P. L. G.}, title = {Transpiration and canopy conductance of secondary vegetation in the eastern Amazon}, journal = {Agricultural and Forest Meteorology}, year = {2002}, volume = {112}, number = {2}, pages = {103--121}, url = {://WOS:000177563000003}, doi = {https://doi.org/10.1016/s0168-1923(02)00044-8} } |
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Sombroek, W. | Amazon landforms and soils in relation to biological diversity [BibTeX] |
2000 | Acta Amazonica Vol. 30, pp. 81-100 |
article | |
BibTeX:
@article{sombroek_amazon_2000, author = {Sombroek, W.G.}, title = {Amazon landforms and soils in relation to biological diversity}, journal = {Acta Amazonica}, year = {2000}, volume = {30}, pages = {81--100} } |
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Sombroek, W., Ruivo, M.D., Fearnside, P.M., Glaser, B. and Lehmann, J. | Amazonian Dark Earths as carbon stores and sinks [BibTeX] |
2004 | Amazonian Dark Earths: Origin, Properties, Management, pp. 125-139 | incollection | DOI URL |
BibTeX:
@incollection{lehmann_amazonian_2004, author = {Sombroek, W. and Ruivo, M. D. and Fearnside, P. M. and Glaser, B. and Lehmann, J.}, title = {Amazonian Dark Earths as carbon stores and sinks}, booktitle = {Amazonian Dark Earths: Origin, Properties, Management}, year = {2004}, pages = {125--139}, url = {://WOS:000221508500007 http://www.springerlink.com/content/n338191276765p65/}, doi = {https://doi.org/10.1007/1-4020-2597-1_7} } |
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Solander, K.C., Newman, B.D., Carioca de Araujo, A., Barnard, H.R., Berry, Z.C., Bonal, D., Bretfeld, M., Burban, B., Antonio Candido, L., Célleri, R., Chambers, J.Q., Christoffersen, B.O., Detto, M., Dorigo, W.A., Ewers, B.E., José Filgueiras Ferreira, S., Knohl, A., Leung, L.R., McDowell, N.G., Miller, G.R., Terezinha Ferreira Monteiro, M., Moore, G.W., Negron-Juarez, R., Saleska, S.R., Stiegler, C., Tomasella, J. and Xu, C. | The pantropical response of soil moisture to El Niño [BibTeX] |
2020 | Hydrol. Earth Syst. Sci. Vol. 24(5), pp. 2303-2322 |
article | DOI URL |
BibTeX:
@article{solander_pantropical_2020, author = {Solander, K. C. and Newman, B. D. and Carioca de Araujo, A. and Barnard, H. R. and Berry, Z. C. and Bonal, D. and Bretfeld, M. and Burban, B. and Antonio Candido, L. and Célleri, R. and Chambers, J. Q. and Christoffersen, B. O. and Detto, M. and Dorigo, W. A. and Ewers, B. E. and José Filgueiras Ferreira, S. and Knohl, A. and Leung, L. R. and McDowell, N. G. and Miller, G. R. and Terezinha Ferreira Monteiro, M. and Moore, G. W. and Negron-Juarez, R. and Saleska, S. R. and Stiegler, C. and Tomasella, J. and Xu, C.}, title = {The pantropical response of soil moisture to El Niño}, journal = {Hydrol. Earth Syst. Sci.}, year = {2020}, volume = {24}, number = {5}, pages = {2303--2322}, url = {https://hess.copernicus.org/articles/24/2303/2020/}, doi = {https://doi.org/10.5194/hess-24-2303-2020} } |
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Soares-Filho, B.S., Garcia, R.A., Rodrigues, H.O., Moro, S. and Nepstad, D.C. | Nexos Entre as Dimensões Socioeconômicas e o Desmatamento na Amazônia: A Caminho de um Modelo Integrado [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 181-217 |
incollection | |
BibTeX:
@incollection{batistella_nexos_2008, author = {Soares-Filho, Britaldo Silveira and Garcia, Ricardo Alexandrino and Rodrigues, Hermann Oliveira and Moro, Sueli and Nepstad, Daniel Curtis}, title = {Nexos Entre as Dimensões Socioeconômicas e o Desmatamento na Amazônia: A Caminho de um Modelo Integrado}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {181--217}, note = {Section: 2} } |
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Soares-Filho, B., Silvestrini, R., Nepstad, D., Brando, P., Rodrigues, H., Alencar, A., Coe, M., Locks, C., Lima, L., Hissa, L. and Stickler, C. | Forest fragmentation, climate change and understory fire regimes on the Amazonian landscapes of the Xingu headwaters | 2012 | Landscape Ecol. Vol. 27(4), pp. DOI 10.1007/s10980-012-9723-6 |
article | DOI URL |
Abstract: Understory fire modeling is a key tool to investigate the cornerstone concept of landscape ecology, i.e. how ecological processes relate to landscape structure and dynamics. Within this context, we developed FISC-a model that simulates fire ignition and spread and its effects on the forest carbon balance. FISC is dynamically coupled to a land-use change model to simulate fire regimes on the Amazonian landscapes of the Xingu Headwaters under deforestation, climate change, and land-use management scenarios. FISC incorporates a stochastic cellular automata approach to simulate fire spread across agricultural and forested lands. CARLUC, nested in FISC, simulates fuel dynamics, forest regrowth, and carbon emissions. Simulations of fire regimes under modeled scenarios revealed that the major current and future driver of understory fires is forest fragmentation rather than climate change. Fire intensity proved closely related to the landscape structure of the remaining forest. While climate change may increase the percentage of forest burned outside protected areas by 30% over the next four decades, deforestation alone may double it. Nevertheless, a scenario of forest recovery and better land-use management would abate fire intensity by 18% even in the face of climate change. Over this time period, the total carbon balance of the Xingu's forests varies from an average net sink of 1.6 ton ha(-1) year(-1) in the absence of climate change, fire and deforestation to a source of -0.1 ton ha(-1) year(-1) in a scenario that incorporates these three processes. | |||||
BibTeX:
@article{soares-filho_forest_2012, author = {Soares-Filho, B. and Silvestrini, R. and Nepstad, D. and Brando, P. and Rodrigues, H. and Alencar, A. and Coe, M. and Locks, C. and Lima, L. and Hissa, L. and Stickler, C.}, title = {Forest fragmentation, climate change and understory fire regimes on the Amazonian landscapes of the Xingu headwaters}, journal = {Landscape Ecol.}, year = {2012}, volume = {27}, number = {4}, pages = {DOI 10.1007/s10980--012--9723--6}, url = {://000302346900009}, doi = {https://doi.org/10.1007/s10980-012-9723-6} } |
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Soares-Filho, B., Moutinho, P., Nepstad, D., Anderson, A., Rodrigues, H., Garcia, R., Dietzsch, L., Merry, F., Bowman, M., Hissa, L., Silvestrini, R. and Maretti, C. | Role of Brazilian Amazon protected areas in climate change mitigation | 2010 | Proceedings of the National Academy of Sciences of the United States of America Vol. 107(24), pp. 10821-10826 |
article | DOI URL |
Abstract: Protected areas (PAs) now shelter 54% of the remaining forests of the Brazilian Amazon and contain 56% of its forest carbon. However, the role of these PAs in reducing carbon fluxes to the atmosphere from deforestation and their associated costs are still uncertain. To fill this gap, we analyzed the effect of each of 595 Brazilian Amazon PAs on deforestation using a metric that accounts for differences in probability of deforestation in areas of pairwise comparison. We found that the three major categories of PA (indigenous land, strictly protected, and sustainable use) showed an inhibitory effect, on average, between 1997 and 2008. Of 206 PAs created after the year 1999, 115 showed increased effectiveness after their designation as protected. The recent expansion of PAs in the Brazilian Amazon was responsible for 37% of the region's total reduction in deforestation between 2004 and 2006 without provoking leakage. All PAs, if fully implemented, have the potential to avoid 8.0 +/- 2.8 Pg of carbon emissions by 2050. Effectively implementing PAs in zones under high current or future anthropogenic threat offers high payoffs for reducing carbon emissions, and as a result should receive special attention in planning investments for regional conservation. Nevertheless, this strategy demands prompt and predictable resource streams. The Amazon PA network represents a cost of US$147 +/- 53 billion (net present value) for Brazil in terms of forgone profits and investments needed for their consolidation. These costs could be partially compensated by an international climate accord that includes economic incentives for tropical countries that reduce their carbon emissions from deforestation and forest degradation. | |||||
BibTeX:
@article{soares-filho_role_2010, author = {Soares-Filho, Britaldo and Moutinho, Paulo and Nepstad, Daniel and Anderson, Anthony and Rodrigues, Hermann and Garcia, Ricardo and Dietzsch, Laura and Merry, Frank and Bowman, Maria and Hissa, Leticia and Silvestrini, Rafaella and Maretti, Claudio}, title = {Role of Brazilian Amazon protected areas in climate change mitigation}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2010}, volume = {107}, number = {24}, pages = {10821--10826}, note = {Edition: 2010/05/28}, url = {://WOS:000278807400011}, doi = {https://doi.org/10.1073/pnas.0913048107} } |
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Soares Neto, T., Carvalho Jr., J.A., Cortez, E., Azevedo, R., Oliveira, R., Fidalgo, W. and Santos, J. | Laboratory evaluation of Amazon forest biomass burning emissions [BibTeX] |
2011 | Atmospheric Environment Vol. 45(39), pp. 7455-7461 |
article | DOI |
BibTeX:
@article{soares_neto_laboratory_2011, author = {Soares Neto, T.G. and J.A., Carvalho Jr. and Cortez, E.V. and Azevedo, R.G. and Oliveira, R.A. and Fidalgo, W.R.R. and Santos, J.C.}, title = {Laboratory evaluation of Amazon forest biomass burning emissions}, journal = {Atmospheric Environment}, year = {2011}, volume = {45}, number = {39}, pages = {7455--7461}, doi = {https://doi.org/10.1016/j.atmosenv.2011.05.003} } |
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Soares, B.S., Nepstad, D.C., Curran, L.M., Cerqueira, G.C., Garcia, R.A., Ramos, C.A., Voll, E., McDonald, A., Lefebvre, P. and Schlesinger, P. | Modelling conservation in the Amazon basin | 2006 | Nature Vol. 440(7083), pp. 520-523 |
article | DOI URL |
Abstract: Expansion of the cattle and soy industries in the Amazon basin has increased deforestation rates and will soon push all-weather highways into the region's core(1-4). In the face of this growing pressure, a comprehensive conservation strategy for the Amazon basin should protect its watersheds, the full range of species and ecosystem diversity, and the stability of regional climates. Here we report that protected areas in the Amazon basin-the central feature of prevailing conservation approaches(5-8)-are an important but insufficient component of this strategy, based on policy-sensitive simulations of future deforestation. By 2050, current trends in agricultural expansion will eliminate a total of 40% of Amazon forests, including at least two-thirds of the forest cover of six major watersheds and 12 ecoregions, releasing 32 +/- 8 Pg of carbon to the atmosphere. One-quarter of the 382 mammalian species examined will lose more than 40% of the forest within their Amazon ranges. Although an expanded and enforced network of protected areas could avoid as much as one-third of this projected forest loss, conservation on private lands is also essential. Expanding market pressures for sound land management and prevention of forest clearing on lands unsuitable for agriculture are critical ingredients of a strategy for comprehensive conservation(3,4). | |||||
BibTeX:
@article{soares_modelling_2006, author = {Soares, B. S. and Nepstad, D. C. and Curran, L. M. and Cerqueira, G. C. and Garcia, R. A. and Ramos, C. A. and Voll, E. and McDonald, A. and Lefebvre, P. and Schlesinger, P.}, title = {Modelling conservation in the Amazon basin}, journal = {Nature}, year = {2006}, volume = {440}, number = {7083}, pages = {520--523}, note = {Edition: 2006/03/24}, url = {://WOS:000236176100054}, doi = {https://doi.org/10.1038/nature04389} } |
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Soares, B., Alencar, A., Nepstad, D., Cerqueira, G., Diaz, M.D.V., Rivero, S., Solorzano, L. and Voll, E. | Simulating the response of land-cover changes to road paving and governance along a major Amazon highway: the Santarem-Cuiaba corridor | 2004 | Global Change Biology Vol. 10(5), pp. 745-764 |
article | DOI URL |
Abstract: The spatial distribution of human activities in forest frontier regions is strongly influenced by transportation infrastructure. With the planned paving of 6000 km of highway in the Amazon Basin, agricultural frontier expansion will follow, triggering potentially large changes in the location and rate of deforestation. We developed a land-cover change simulation model that is responsive to road paving and policy intervention scenarios for the BR-163 highway in central Amazonia. This corridor links the cities of Cuiaba, in central Brazil, and Santarem, on the southern margin of the Amazon River. It connects important soybean production regions and burgeoning population centers in Mato Grosso State with the international port of Santarem, but 1000 km of this road are still not paved. It is within this context that the Brazilian government has prioritized the paving of this road to turn it into a major soybean exportation facility. The model assesses the impacts of this road paving within four scenarios: two population scenarios (high and moderate growth) and two policy intervention scenarios. In the 'business-as-usual' policy scenario, the responses of deforestation and land abandonment to road paving are estimated based on historical rates of Amazon regions that had a major road paved. In the 'governance' scenario, several plausible improvements in the enforcement of environmental regulations, support for sustainable land-use systems, and local institutional capacity are invoked to modify the historical rates. Model inputs include data collected during expeditions and through participatory mapping exercises conducted with agents from four major frontier types along the road. The model has two components. A scenario-generating submodel is coupled to a landscape dynamics simulator, 'DINAMICA', which spatially allocates the land-cover transitions using a GIS database. The model was run for 30 years, divided into annual time steps. It predicted more than twice as much deforestation along the corridor in business-as-usual vs. governance scenarios. The model demonstrates how field data gathered along a 1000 km corridor can be used to develop plausible scenarios of future land-cover change trajectories that are relevant to both global change science and the decision-making process of governments and civil society in an important rainforest region. | |||||
BibTeX:
@article{soares_simulating_2004, author = {Soares, B. and Alencar, A. and Nepstad, D. and Cerqueira, G. and Diaz, M. D. V. and Rivero, S. and Solorzano, L. and Voll, E.}, title = {Simulating the response of land-cover changes to road paving and governance along a major Amazon highway: the Santarem-Cuiaba corridor}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {745--764}, url = {://WOS:000221421600016}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00769.x} } |
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Snider, G., Weagle, C.L., Martin, R.V., Van Donkelaar, A., Conrad, K., Cunningham, D., Gordon, C., Zwicker, M., Akoshile, C., Artaxo, P., Anh, N.X., Brook, J., Dong, J., Garland, R.M., Greenwald, R., Griffith, D., He, K., Holben, B.N., Kahn, R., Koren, I., Lagrosas, N., Lestari, P., Ma, Z., Vanderlei Martins, J., Quel, E.J. and al. , e. | SPARTAN: a global network to evaluate and enhance satellite-based estimates of ground-level particulate matter for global health applications [BibTeX] |
2015 | Atmospheric Measurement Techniques Vol. 8, pp. 505-521 |
article | |
BibTeX:
@article{snider_spartan_2015, author = {Snider, G. and Weagle, C. L. and Martin, R. V. and Van Donkelaar, A. and Conrad, K. and Cunningham, D. and Gordon, C. and Zwicker, M. and Akoshile, C. and Artaxo, P. and Anh, N. X. and Brook, J. and Dong, J. and Garland, R. M. and Greenwald, R. and Griffith, D. and He, K. and Holben, B. N. and Kahn, R. and Koren, I. and Lagrosas, N. and Lestari, P. and Ma, Z. and Vanderlei Martins, J. and Quel, E. J. and al., et}, title = {SPARTAN: a global network to evaluate and enhance satellite-based estimates of ground-level particulate matter for global health applications}, journal = {Atmospheric Measurement Techniques}, year = {2015}, volume = {8}, pages = {505--521} } |
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Smith, M.N., Taylor, T.C., van Haren, J., Rosolem, R., Restrepo-Coupe, N., Adams, J., Wu, J., de Oliveira, R.C., da Silva, R., de Araujo, A.C., de Camargo, P.B., Huxman, T.E. and Saleska, S.R. | Empirical evidence for resilience of tropical forest photosynthesis in a warmer world | 2020 | Nature Plants Vol. 6(10), pp. 1225-1230 |
article | DOI URL |
Abstract: Tropical forests may be vulnerable to climate change1–3 if photosynthetic carbon uptake currently operates near a high temperature limit4–6. Predicting tropical forest function requires understanding the relative contributions of two mechanisms of high-temperature photosynthetic declines: stomatal limitation (H1), an indirect response due to temperature-associated changes in atmospheric vapour pressure deficit (VPD)7, and biochemical restrictions (H2), a direct temperature response8,9. Their relative control predicts different outcomes—H1 is expected to diminish with stomatal responses to future co-occurring elevated atmospheric [CO2], whereas H2 portends declining photosynthesis with increasing temperatures. Distinguishing the two mechanisms at high temperatures is therefore critical, but difficult because VPD is highly correlated with temperature in natural settings. We used a forest mesocosm to quantify the sensitivity of tropical gross ecosystem productivity (GEP) to future temperature regimes while constraining VPD by controlling humidity. We then analytically decoupled temperature and VPD effects under current climate with flux-tower-derived GEP trends in situ from four tropical forest sites. Both approaches showed consistent, negative sensitivity of GEP to VPD but little direct response to temperature. Importantly, in the mesocosm at low VPD, GEP persisted up to 38 °C, a temperature exceeding projections for tropical forests in 2100 (ref. 10). If elevated [CO2] mitigates VPD-induced stomatal limitation through enhanced water-use efficiency as hypothesized9,11, tropical forest photosynthesis may have a margin of resilience to future warming. | |||||
BibTeX:
@article{smith_empirical_2020, author = {Smith, Marielle N. and Taylor, Tyeen C. and van Haren, Joost and Rosolem, Rafael and Restrepo-Coupe, Natalia and Adams, John and Wu, Jin and de Oliveira, Raimundo C. and da Silva, Rodrigo and de Araujo, Alessandro C. and de Camargo, Plinio B. and Huxman, Travis E. and Saleska, Scott R.}, title = {Empirical evidence for resilience of tropical forest photosynthesis in a warmer world}, journal = {Nature Plants}, year = {2020}, volume = {6}, number = {10}, pages = {1225--1230}, url = {https://doi.org/10.1038/s41477-020-00780-2}, doi = {https://doi.org/10.1038/s41477-020-00780-2} } |
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Smith, M.N., Stark, S.C., Taylor, T.C., Ferreira, M.L., Oliveira, E.d., Restrepo‐Coupe, N., Chen, S., Woodcock, T., Santos, D.B.d., Alves, L.F., Figueira, M., Camargo, P.B.d., Oliveira, R.C.d., Aragão, L.E.O.C., Falk, D.A., McMahon, S.M., Huxman, T.E. and Saleska, S.R. | Seasonal and drought‐related changes in leaf area profiles depend on height and light environment in an Amazon forest [BibTeX] |
2019 | New Phytologist Vol. 222(3) |
article | |
BibTeX:
@article{smith_seasonal_2019, author = {Smith, Marielle N. and Stark, Scott C. and Taylor, Tyeen C. and Ferreira, Mauricio L. and Oliveira, Eronaldo de and Restrepo‐Coupe, Natalia and Chen, Shuli and Woodcock, Tara and Santos, Darlisson Bentes dos and Alves, Luciana F. and Figueira, Michela and Camargo, Plinio B. de and Oliveira, Raimundo C. de and Aragão, Luiz E. O. C. and Falk, Donald A. and McMahon, Sean M. and Huxman, Travis E. and Saleska, Scott R.}, title = {Seasonal and drought‐related changes in leaf area profiles depend on height and light environment in an Amazon forest}, journal = {New Phytologist}, year = {2019}, volume = {222}, number = {3} } |
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Smith, L.K., Melack, J.M. and Hammond, D.E. | Carbon, nitrogen, and phosphorus content and (210)Pb-derived burial rates in sediments of an Amazon floodplain lake | 2003 | Amazoniana-Limnologia Et Oecologia Regionalis Systemae Fluminis Amazonas Vol. 17(3-4), pp. 413-436 |
article | URL |
Abstract: The C, N and P content of surficial sediments, (210)Pb-derived accumulation rates, and burial rates of C, N and P were determined in Lake Calado, a dendritic lake located on the floodplain of the central Amazon basin. A significant positive, linear relationship was found between distance from the river and C, N and P content of the sediments (r(2) = 0.93, r(2) = 0.92, p textless0.001 for C and N, respectively, and r(2) = 0.64, p textless0.05 for P), indicative of high organic matter content on the floodplain and a greater proportion of clay near the river. Average sediment accumulation rates derived from two cores collected from each of three stations ranged from 41 to 117 mg cm(-2) yr(-1). Lake-wide, annual burial rates are estimated to be 3.5 mol cm(-2), 0.28 mol N m(-2) and 0.016 mol P m(-2). | |||||
BibTeX:
@article{smith_carbon_2003, author = {Smith, L. K. and Melack, J. M. and Hammond, D. E.}, title = {Carbon, nitrogen, and phosphorus content and (210)Pb-derived burial rates in sediments of an Amazon floodplain lake}, journal = {Amazoniana-Limnologia Et Oecologia Regionalis Systemae Fluminis Amazonas}, year = {2003}, volume = {17}, number = {3-4}, pages = {413--436}, url = {://WOS:000188382100009} } |
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Smith, C.K., Oliveira, F.D., Gholz, H.L. and Baima, A. | Soil carbon stocks after forest conversion to tree plantations in lowland Amazonia, Brazil | 2002 | Forest Ecology and Management Vol. 164(1-3), pp. 257-263 |
article | DOI URL |
Abstract: The large-scale conversion of Amazonian forest to other land-uses is altering carbon (C) stocks in this important eco-region. and these changes will in turn influence global C cycling. In this study, we evaluated changes of forest floor and surface soil C storage caused by converting primary Amazonian forest to tree plantations at the Curua-Una Forest Reserve, Para, Brazil. The plantations were established between 1959 and 1973 and they consisted of replicated plots of Pinus caribaea var. hondurensis Barrett and Golfari, Carapa guianensis Aubl.. Euxylophora paraensis Hub., and a Leguminosae combination (Parkia multijuga Benth., Dinizia excelsa Ducke, Dalbergia nigra Fr. All. In surface soils (0-20 cm), mean C stocks ranged from 7 (P. caribaea) to 11 kg m(-2) (E. paraensis). Fine litter C inputs ranged from 380 g m(-2) (E. paraensis) to 513 g m(-2) (P. caribaea), and forest floor C stocks (fine material) ranged from 359 (E. paraensis) to 542 g m(-2) (P. caribaea). R caribaea had the smallest fine root biomass-C (less than or equal to2 mm diameter) in the forest floor and surface soils (101 g m(-2)). Relative to adjacent terra fir-me forest, total C stocks in the surface mineral soil, forest floor, and fine roots (live + dead) in the plantations ranged from a net decrease of 13% W caribaea) to a net increase of 7% (E. paraensis). (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{smith_soil_2002, author = {Smith, C. K. and Oliveira, F. D. and Gholz, H. L. and Baima, A.}, title = {Soil carbon stocks after forest conversion to tree plantations in lowland Amazonia, Brazil}, journal = {Forest Ecology and Management}, year = {2002}, volume = {164}, number = {1-3}, pages = {257--263}, url = {://WOS:000176604900020}, doi = {https://doi.org/10.1016/s0378-1127(01)00599-0} } |
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Sisenando, H.A., Batistuzzo de Medeiros, S.R., Saldiva, P.H.N., Artaxo, P. and Hacon, S.S. | Genotoxic potential generated by biomass burning in the Brazilian Legal Amazon by Tradescantia micronucleus bioassay: a toxicity assessment study | 2011 | Environmental Health Vol. 10, pp. 41 |
article | DOI URL |
Abstract: Background: The Brazilian Amazon has suffered impacts from non-sustainable economic development, especially owing to the expansion of agricultural commodities into forest areas. The Tangara da Serra region, located in the southern of the Legal Amazon, is characterized by non-mechanized sugar cane production. In addition, it lies on the dispersion path of the pollution plume generated by biomass burning. The aim of this study was to assess the genotoxic potential of the atmosphere in the Tangara da Serra region, using Tradescantia pallida as in situ bioindicator. Methods: The study was conducted during the dry and rainy seasons, where the plants were exposed to two types of exposure, active and passive. Results: The results showed that in all the sampling seasons, irrespective of exposure type, there was an increase in micronucleus frequency, compared to control and that it was statistically significant in the dry season. A strong and significant relationship was also observed between the increase in micronucleus incidence and the rise in fine particulate matter, and hospital morbidity from respiratory diseases in children. Conclusions: Based on the results, we demonstrated that pollutants generated by biomass burning in the Brazilian Amazon can induce genetic damage in test plants that was more prominent during dry season, and correlated with the level of particulates and elevated respiratory morbidity. | |||||
BibTeX:
@article{sisenando_genotoxic_2011, author = {Sisenando, Herbert A. and Batistuzzo de Medeiros, Silvia R. and Saldiva, Paulo H. N. and Artaxo, Paulo and Hacon, Sandra S.}, title = {Genotoxic potential generated by biomass burning in the Brazilian Legal Amazon by Tradescantia micronucleus bioassay: a toxicity assessment study}, journal = {Environmental Health}, year = {2011}, volume = {10}, pages = {41}, note = {Edition: 2011/05/18}, url = {://WOS:000291801300001}, doi = {https://doi.org/10.1186/1476-069x-10-41} } |
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Sisenando Silvia R Batistuzzo de Medeiros, P.A.P.H.N.S.and.S.S.H.H.A. | Micronucleus frequency in children exposed to biomass burning in the Brazilian Legal Amazon region: a case control study. [BibTeX] |
2012 | BMC Oral Health Vol. 12:6 |
article | DOI |
BibTeX:
@article{sisenando_micronucleus_2012, author = {Sisenando, Silvia R Batistuzzo de Medeiros, Paulo Artaxo, Paulo H N Saldiva and Sandra S Hacon., H. A.}, title = {Micronucleus frequency in children exposed to biomass burning in the Brazilian Legal Amazon region: a case control study.}, journal = {BMC Oral Health}, year = {2012}, volume = {12:6}, doi = {https://doi.org/10.1186/1472-6831-12-6} } |
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Siren, A.H. and Brondizio, E.S. | Detecting subtle land use change in tropical forests | 2009 | Applied Geography Vol. 29(2), pp. 201-211 |
article | DOI URL |
Abstract: This paper presents a study of land use and land cover dynamics in an indigenous community in the Amazon, in particular the methods used to deal with problems related to small size of cultivated plots, spectral similarity between land use classes, atmospheric haze and topographic shade. The main focus was on identifying and quantifying cultivated and fallow areas. Based on remote sensing alone, it was possible to identify about half of the fallows younger than 20 years of age. Combining remote sensing with field-based methods, however, it was possible to estimate the number and size of cultivated areas, the extent of fallows up to 65 years of age, as well as the rate of old-growth forest loss. (C) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{siren_detecting_2009, author = {Siren, Anders H. and Brondizio, Eduardo S.}, title = {Detecting subtle land use change in tropical forests}, journal = {Applied Geography}, year = {2009}, volume = {29}, number = {2}, pages = {201--211}, url = {://WOS:000264661800006}, doi = {https://doi.org/10.1016/j.apgeog.2008.08.006} } |
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Siqueira, P., Chapman, B. and McGarragh, G. | The coregistration, calibration, and interpretation of multiseason JERS-1 SAR data over South America | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 389-403 |
article | DOI URL |
Abstract: The Large-Scale Biosphere-Atmosphere(LBA) experiment in Amazonia represents a unique opportunity to make a comprehensive study of the Amazon region and its component ecosystems. To make sense of the field studies and to generalize the results from them, remote sensing techniques and comprehensive mapping are critical elements for producing region-wide science results. In this paper, we present the processing work done for one such mapping campaign, that of the JERS-1 L-band two season (low and high-flood) SAR data collected in 1995 and 1996. Specifically, to make a useable resource for other LBA researchers to explore, the datasets from the two seasons had to be coregistered (to a sub-pixel level), radiometrically calibrated, and interpreted to verify the quality of the data. This paper describes the techniques used to achieve these goals and an estimate of the land cover based on a simple classification of the data. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{siqueira_coregistration_2003, author = {Siqueira, P. and Chapman, B. and McGarragh, G.}, title = {The coregistration, calibration, and interpretation of multiseason JERS-1 SAR data over South America}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {389--403}, url = {://WOS:000186827400002}, doi = {https://doi.org/10.1016/j.rse.2002.12.002} } |
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Siqueira Júnior, J., Tomasella, J. and Rodriguez, D. | Impacts of future climatic and land cover changes on the hydrological regime of the Madeira River basin [BibTeX] |
2015 | Climatic Change Vol. 129, pp. 117-129 |
article | |
BibTeX:
@article{siqueira_junior_impacts_2015, author = {Siqueira Júnior, J.L. and Tomasella, J. and Rodriguez, D.A.}, title = {Impacts of future climatic and land cover changes on the hydrological regime of the Madeira River basin}, journal = {Climatic Change}, year = {2015}, volume = {129}, pages = {117--129} } |
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Siqueira, J.R. and Machado, L.A.T. | Influence of the frontal systems on the day-to-day convection variability over South America | 2004 | Journal of Climate Vol. 17(9), pp. 1754-1766 |
article | DOI URL |
Abstract: Cold cloud-top fractions derived from International Satellite Cloud Climatology Project images and latitude time diagrams are used to study the interaction of frontal systems with tropical convection over South America (SA). An 11-yr climatology for three frequent types of frontal system-tropical convection interaction is built, and the associated day-to-day convection variability is described using satellite images, complex principal components, and wavelet transforms. Type 1 is frequent throughout the year, especially in austral summer, and is characterized by the penetration of a cold front in subtropical SA that interacts with tropical convection and moves with it into lower tropical latitudes. Type 2 is also more frequent in austral summer and is characterized by Amazon convection and enhancement of a quasi-stationary northwest-southeast-oriented band of convection extending from the Amazon basin to subtropical SA along the passage of a cold front in the subtropics. When the type 2 pattern remains longer than 4 days over SA, it often characterizes the South Atlantic convergence zone. Type 3, which is more frequent in austral winter, is represented by a quasi-stationary cold front in subtropical SA and midlatitudes without significant interaction with tropical convection. Predominant day-to-day fluctuation time scales of convection associated with the three types were identified, ranging from 5 to 7 days in the Tropics (types 1 and 2) and subtropics (type 3). By evaluating circulation patterns over SA using National Centers for Environmental Prediction analysis at 850 and 200 hPa, the northeastward propagation of a transient cyclonic vortex organized by a cold front in southeast SA and Amazon moisture flows is the main feature of the type 1 pattern at low levels. A cyclonic vortex similar to the one in type 1 but quasi-stationary in the subtropics is remarkable for the type 2 pattern, while upper-level cyclonic vortices in northeast Brazil and the existence of a subtropical jet seem to contribute to the blocking configuration of cold fronts in subtropical SA that characterizes the type 3 pattern. | |||||
BibTeX:
@article{siqueira_influence_2004, author = {Siqueira, J. R. and Machado, L. A. T.}, title = {Influence of the frontal systems on the day-to-day convection variability over South America}, journal = {Journal of Climate}, year = {2004}, volume = {17}, number = {9}, pages = {1754--1766}, url = {://WOS:000220951100002}, doi = {https://doi.org/10.1175/1520-0442(2004)017%3C1754:iotfso%3E2.0.co;2} } |
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Sippel, S.J., Hamilton, S.K., Melack, J.M. and Novo, E.M.M. | Passive microwave observations of inundation area and the area/stage relation in the Amazon River floodplain | 1998 | International Journal of Remote Sensing Vol. 19(16), pp. 3055-3074 |
article | DOI URL |
Abstract: Inundation patterns in Amazon River floodplains are revealed by analysis of the 37 GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer on the Nimbus-7 satellite. Flooded area is estimated at monthly intervals for January 1979 through August 1987 using mixing models that account for the major landscape units with distinctive microwave emission characteristics. Results are presented separately for 12 longitudinal reaches along the Amazon River main stem in Brazil as well as for three major tributaries (the Jurua, Purus and Madeira rivers). The total area along the Amazon River main stem that was flooded (including both floodplain and open water) varied between 19000 and 91000 km(2). The: correlation between flooded area and river stage is used to develop a predictive relationship and reconstruct regional inundation patterns in the floodplain of the Amazon River main stem over the past 94 years of stage records (1903-1996). The mean flooded area along the Amazon River during this 94-year period was 46800 km(2), of which the open-water surfaces of river channels and floodplain lakes comprised about 20700 km(2). | |||||
BibTeX:
@article{sippel_passive_1998, author = {Sippel, S. J. and Hamilton, S. K. and Melack, J. M. and Novo, E. M. M.}, title = {Passive microwave observations of inundation area and the area/stage relation in the Amazon River floodplain}, journal = {International Journal of Remote Sensing}, year = {1998}, volume = {19}, number = {16}, pages = {3055--3074}, url = {://WOS:000076934300003}, doi = {https://doi.org/10.1080/014311698214181} } |
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Singer, C.E., Lopez-Gomez, I., Zhang, X. and Schneider, T. | Top-of-Atmosphere Albedo Bias from Neglecting Three-Dimensional Cloud Radiative Effects [BibTeX] |
2021 | Journal of the Atmospheric Sciences Vol. 78(12), pp. 4053-4069 |
article | |
BibTeX:
@article{singer_top--atmosphere_2021, author = {Singer, Clare E. and Lopez-Gomez, Ignacio and Zhang, Xiyue and Schneider, Tapio}, title = {Top-of-Atmosphere Albedo Bias from Neglecting Three-Dimensional Cloud Radiative Effects}, journal = {Journal of the Atmospheric Sciences}, year = {2021}, volume = {78}, number = {12}, pages = {4053--4069} } |
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Simon, E., Meixner, F.X., Rummel, U., Ganzeveld, L., Ammann, C. and Kesselmeier, J. | Coupled carbon-water exchange of the Amazon rain forest, II. Comparison of predicted and observed seasonal exchange of energy, CO72, isoprene and ozone at a remote site in Rondonia | 2005 | Biogeosciences Vol. 2(3), pp. 255-275 |
article | URL |
Abstract: A one-dimensional multi-layer scheme describing the coupled exchange of energy and CO2, the emission of isoprene and the dry deposition of ozone is applied to a rain forest canopy in southwest Amazonia. The model was constrained using mean diel cycles of micrometeorological quantities observed during two periods in the wet and dry season 1999. Calculated net fluxes and concentration profiles for both seasonal periods are compared to observations made at two nearby towers. The modeled day- and nighttime thermal stratification of the canopy layer is consistent with observations in dense canopies. The observed and modeled net fluxes above and H2O and CO2 concentration profiles within the canopy show a good agreement. The predicted net carbon sink decreases from 2.5 t C ha(-1) yr(-1) for wet season conditions to 1 t C ha(-1) yr(-1) for dry season conditions, whereas observed and modeled midday Bowen ratio increases from 0.5 to 0.8. The evaluation results confirmed a seasonal variability of leaf physiological parameters, as already suggested in a companion study. The calculated midday canopy net flux of isoprene increased from 7.1 mg C m(-2) h(-1) during the wet season to 11.4 mg C m(-2) h(-1) during the late dry season. Applying a constant emission capacity in all canopy layers, resulted in a disagreement between observed and simulated profiles of isoprene concentrations, suggesting a smaller emission capacity of shade adapted leaves and deposition to the soil or leaf surfaces. Assuming a strong light acclimation of emission capacity, equivalent to a 66% reduction of the standard emission factor for leaves in the lower canopy, resulted in a better agreement of observed and modeled concentration profiles and a 30% reduction of the canopy net flux compared to model calculations with a constant emission factor. The mean calculated ozone flux for dry season conditions at noontime was approximate to 12 nmol m(-2) s(-1), agreeing well with observed values. The corresponding deposition velocity increased from 0.8 cm s(-1) to textgreater 1.6 cm s(-1) in the wet season, which can not be explained by increased stomatal uptake. Considering reasonable physiological changes in stomatal regulation, the modeled value was not larger than 1.05 cm s(-1). Instead, the observed fluxes could be explained with the model by decreasing the cuticular resistance to ozone deposition from 5000 to 1000 s m(-1). | |||||
BibTeX:
@article{simon_coupled_2005, author = {Simon, E. and Meixner, F. X. and Rummel, U. and Ganzeveld, L. and Ammann, C. and Kesselmeier, J.}, title = {Coupled carbon-water exchange of the Amazon rain forest, II. Comparison of predicted and observed seasonal exchange of energy, CO72, isoprene and ozone at a remote site in Rondonia}, journal = {Biogeosciences}, year = {2005}, volume = {2}, number = {3}, pages = {255--275}, url = {://WOS:000236195300003} } |
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Simon, E., Meixner, F.X., Ganzeveld, L. and Kesselmeier, J. | Coupled carbon-water exchange of the Amazon rain forest, I. Model description, parameterization and sensitivity analysis | 2005 | Biogeosciences Vol. 2(3), pp. 231-253 |
article | URL |
Abstract: Detailed one-dimensional multilayer biosphere-atmosphere models, also referred to as CANVEG models, are used for more than a decade to describe coupled water-carbon exchange between the terrestrial vegetation and the lower atmosphere. Within the present study, a modified CANVEG scheme is described. A generic parameterization and characterization of biophysical properties of Amazon rain forest canopies is inferred using available field measurements of canopy structure, in-canopy profiles of horizontal wind speed and radiation, canopy albedo, soil heat flux and soil respiration, photosynthetic capacity and leaf nitrogen as well as leaf level enclosure measurements made on sunlit and shaded branches of several Amazonian tree species during the wet and dry season. The sensitivity of calculated canopy energy and CO2 fluxes to the uncertainty of individual parameter values is assessed. In the companion paper, the predicted seasonal exchange of energy, CO2, ozone and isoprene is compared to observations. A bi-modal distribution of leaf area density with a total leaf area index of 6 is inferred from several observations in Amazonia. Predicted light attenuation within the canopy agrees reasonably well with observations made at different field sites. A comparison of predicted and observed canopy albedo shows a high model sensitivity to the leaf optical parameters for near-infrared short-wave radiation (NIR). The predictions agree much better with observations when the leaf reflectance and transmission coefficients for NIR are reduced by 25-40%. Available vertical distributions of photosynthetic capacity and leaf nitrogen concentration suggest a low but significant light acclimation of the rain forest canopy that scales nearly linearly with accumulated leaf area. Evaluation of the biochemical leaf model, using the enclosure measurements, showed that recommended parameter values describing the photosynthetic light response, have to be optimized. Otherwise, predicted net assimilation is overestimated by 30-50%. Two stomatal models have been tested, which apply a well established semi-empirical relationship between stomatal conductance and net assimilation. Both models differ in the way they describe the influence of humidity on stomatal response. However, they show a very similar performance within the range of observed environmental conditions. The agreement between predicted and observed stomatal conductance rates is reasonable. In general, the leaf level data suggests seasonal physiological changes, which can be reproduced reasonably well by assuming increased stomatal conductance rates during the wet season, and decreased assimilation rates during the dry season. The sensitivity of the predicted canopy fluxes of energy and CO2 to the parameterization of canopy structure, the leaf optical parameters, and the scaling of photosynthetic parameters is relatively low (1-12%), with respect to parameter uncertainty. In contrast, modifying leaf model parameters within their uncertainty range results in much larger changes of the predicted canopy net fluxes (5-35%). | |||||
BibTeX:
@article{simon_coupled_2005-1, author = {Simon, E. and Meixner, F. X. and Ganzeveld, L. and Kesselmeier, J.}, title = {Coupled carbon-water exchange of the Amazon rain forest, I. Model description, parameterization and sensitivity analysis}, journal = {Biogeosciences}, year = {2005}, volume = {2}, number = {3}, pages = {231--253}, url = {://WOS:000236195300002} } |
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Simon, E., Kuhn, U., Rottenberger, S., Meixner, F.X. and Kesselmeier, J. | Coupling isoprene and monoterpene emissions from Amazonian tree species with physiological and environmental parameters using a neural network approach | 2005 | Plant Cell and Environment Vol. 28(3), pp. 287-301 |
article | DOI URL |
Abstract: The ability to predict isoprene emissions from plants is important for predicting atmospheric chemistry. To improve the basis for prediction capability, data obtained from continuous field measurements of isoprene and monoterpene emissions from three Amazonian tree species were related to observed environmental and leaf physiological parameters using a new neural network approach. The environmental parameters included leaf temperature, light, relative humidity, water vapour pressure deficit, and the history of ambient temperature and ozone concentration, whereas the physiological parameters included stomatal conductance, assimilation and intercellular CO2 concentration. The neural approach with 24 different combinations of these parameters was applied to predict the emission variability observed during short time periods (2-3 d) with individual tree branches and, on a longer-term scale, in aggregated data sets from different seasons, leaf developmental stage, and light environment. The results were compared to the quasi standard emission algorithm for isoprene. On the short-term scale, good agreement (r(2) approximate to 0.9) was obtained between observations and predictions of the standard algorithm as well as predictions of the neural network using the same input parameters (leaf temperature and light). When these predictors were used to model the long-term emission variability, r(2) was reduced to textless 0.5 for both approaches. Remarkably, for the neural technique, more than 50% of the unexplained variance could be explained by the mean temperature of the preceding 36 h. An even better network performance was obtained with physiological parameter combinations (r(2) textgreater 0.9) suggesting a strong and applicable link between isoprenoid emission and leaf primary metabolism. | |||||
BibTeX:
@article{simon_coupling_2005, author = {Simon, E. and Kuhn, U. and Rottenberger, S. and Meixner, F. X. and Kesselmeier, J.}, title = {Coupling isoprene and monoterpene emissions from Amazonian tree species with physiological and environmental parameters using a neural network approach}, journal = {Plant Cell and Environment}, year = {2005}, volume = {28}, number = {3}, pages = {287--301}, url = {://WOS:000227087600003}, doi = {https://doi.org/10.1111/j.1365-3040.2004.01278.x} } |
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Simon, C., Pimentel, T.P., Monteiro, M.T.F., Candido, L.A., Gastmans, D., Geilmann, H., da Costa Oliveira, R., Rocha, J.B., Pires, E., Quesada, C.A., Forsberg, B.R., Ferreira, S.J.F., da Cunha, H.B. and Gleixner, G. | Molecular links between whitesand ecosystems and blackwater formation in the Rio Negro watershed | 2021 | Geochimica et Cosmochimica Acta Vol. 311, pp. 274-291 |
article | DOI URL |
Abstract: Tropical rivers such as the Rio Negro constitute a major portion of the global aquatic flux of dissolved organic carbon (DOC) entering the ocean, but the exact amount, source contributions and fate of terrestrial DOC remain unknown. We investigated the role of valley and upland whitesand ecosystems (WSEs) and terra firme plateaus in forming blackwater tributaries in the Rio Negro basin to develop novel constraints for the terrestrial export of carbon. 5709 molecular markers from ground- and surface waters of two contrasting valley and upland sites feeding Rio Negro tributaries were identified by ultrahigh resolution mass spectrometry (FT-MS), analyzed by multivariate statistics and compared to known Rio Negro markers. In a Principal Coordinates Analysis, valley and upland DOC molecular composition differed by 78% from plateau DOC, which was characterized by reworked, aliphatic and unsaturated N- and S-containing molecules, while valley and upland DOC contained mainly condensed aromatics, aromatics and oxidized unsaturated structures. Valley and upland samples differed by 10% in molecular DOC composition and by their isotopic content (14C of SPE-DOC, 18O and 2H of water) which indicated differences in hydrology and C turnover. Against expectation, markers of widespread whitesand valleys did not emerge as a major source of Rio Negro markers, but specific upland markers did. Pubchem suggested chromene and benzofuran structures as promising candidates for further study. Our findings indicate that the export of molecular markers diverges from expected transport-limited DOC behavior, and thereby opens new avenues for source annotation beyond DOC quantity. Terrestrial DOC from upland whitesand areas is a major source of specific blackwater molecules missing in the regional ecosystem C balance, whereas C export from the whitesand valleys and especially from terra firme plateaus represents mainly recycled and transformed carbon not directly affecting the ecosystem C balance and possibly, the watersheds downstream molecular signature. Our study highlights the potential of high-resolution techniques to constrain carbon balances of ecosystems and landscapes by novel molecular markers. A comparison with other terrestrial DOM datasets indicated molecular similarities with temperate acidic soils and tropical rivers that warrant further analysis of common DOM markers. Implications, limitations, and future challenges are discussed in the light of potential applications of diagnostic molecular links for DOC source annotation and estimation of terrestrial DOM export in the land-to-ocean continuum. | |||||
BibTeX:
@article{simon_molecular_2021, author = {Simon, C. and Pimentel, T. P. and Monteiro, M. T. F. and Candido, L. A. and Gastmans, D. and Geilmann, H. and da Costa Oliveira, R. and Rocha, J. B. and Pires, E. and Quesada, C. A. and Forsberg, B. R. and Ferreira, S. J. F. and da Cunha, H. B. and Gleixner, G.}, title = {Molecular links between whitesand ecosystems and blackwater formation in the Rio Negro watershed}, journal = {Geochimica et Cosmochimica Acta}, year = {2021}, volume = {311}, pages = {274--291}, url = {https://www.sciencedirect.com/science/article/pii/S001670372100394X}, doi = {https://doi.org/10.1016/j.gca.2021.06.036} } |
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Simmons, C., Walker, R., Arima, E., Aldrich, S. and Caldas, M. | The amazon land war in the south of para | 2007 | Annals of the Association of American Geographers Vol. 97(3), pp. 567-592 |
article | DOI URL |
Abstract: The South of Para, located in the heart of the Brazilian Amazon, has become notorious for violent land struggle. Although land conflict has a long history in Brazil, and today impacts many parts of the country, violence is most severe and persistent here. The purpose of this article is to examine why. Specifically, we consider how a particular Amazonian place, the so-called South of Para, has come to be known as Brazil's most dangerous badland. We begin by considering the predominant literature, which attributes land conflict to the frontier expansion process with intensified struggle emerging in the face of rising property values and demand for private property associated with capitalist development. From this discussion, we distill a concept of the frontier, based on notions of property rights evolution and locational rents. We then empirically test the persistence of place-based violence in the region, and assess the frontier movement through an analysis of transportation costs. Findings from the analyses indicate that the prevalent theorization of frontier violence in Amazonia does little to explain its persistent and pervasive nature in the South of Para. To fill this gap in understanding, we develop an explanation based on the geographic conception of place, and we use contentious politics theory heuristically to elucidate the ways in which general processes interact with place-specific history to engender a landscape of violence. In so doing, we focus on environmental, cognitive, and relational mechanisms (and implicated structures), and attempt to deploy them in an explanatory framework that allows direct observation of the accumulating layers of the region's tragic history. We end by placing our discussion within a political ecological context, and consider the implications of the Amazon Land War for the environment. | |||||
BibTeX:
@article{simmons_amazon_2007, author = {Simmons, C.S. and Walker, R.T. and Arima, E.Y. and Aldrich, S.P. and Caldas, M.M.}, title = {The amazon land war in the south of para}, journal = {Annals of the Association of American Geographers}, year = {2007}, volume = {97}, number = {3}, pages = {567--592}, url = {://WOS:000249562400007}, doi = {https://doi.org/10.1111/j.1467-8306.2007.00564.x} } |
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Simmons, C.S., Walker, R., Arima, E., Aldrich, S. and Caldas, M. | A Guerra Amazônica pela Terra no Sul do Pará [BibTeX] |
2008 | Vol. 1Sociedade, Território e Conflitos: BR-163 em questão, pp. 85-146 |
incollection | |
BibTeX:
@incollection{castro_guerra_2008, author = {Simmons, C. S. and Walker, R. and Arima, E. and Aldrich, S.P. and Caldas, M.}, title = {A Guerra Amazônica pela Terra no Sul do Pará}, booktitle = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, pages = {85--146} } |
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Simmons, C.S. | The political economy of land conflict in the Eastern Brazilian Amazon | 2004 | Annals of the Association of American Geographers Vol. 94(1), pp. 183-206 |
article | DOI URL |
Abstract: An important goal of regional development in the Brazilian Amazon was to enhance social welfare and alleviate dire poverty in other parts of the country by providing land to the poor. Nevertheless, both poverty and landlessness have persisted despite development policies that distributed billions of dollars on highway construction, loans, and outright subsidies. Inequitable land distribution has been held as a prime factor in land conflict across the country. Although episodes of conflict over land are common in Brazilian history, this paper focuses on agrarian issues that arose with the opening of the Amazon frontier in the 1970s. The paper presents a political economy approach that considers the role of hierarchical forces interacting across spatial scales, in creating conditions ripe for land conflict at the local level. The premise is that the Brazilian government, intending to bring about economic and social development, promoted contradictory strategies creating land scarcity. These strategies led to expansion of large ranching operations, creation of conservation units, and demarcation of indigenous reserves, which constrained the pool of land available for small farmer settlement. Empirical analysis employing regression and spatial statistics is used to test the proposed model, advancing previous efforts by applying spatial regression, incorporating improved indicators of conflict and explanatory variables generated by a Geographic Information System (GIS). The findings provide support for some elements of the argument, demonstrating statistically significant relationships between land conflict and land concentration, cattle ranching, and road construction. Finally, a case study analysis of a county in the heart of the land conflict zone is provided, illustrating the interaction of scalar forces, and the articulation of land conflict at the local level. | |||||
BibTeX:
@article{simmons_political_2004, author = {Simmons, C. S.}, title = {The political economy of land conflict in the Eastern Brazilian Amazon}, journal = {Annals of the Association of American Geographers}, year = {2004}, volume = {94}, number = {1}, pages = {183--206}, url = {://WOS:000189291300010}, doi = {https://doi.org/10.1111/j.1467-8306.2004.09401010.x} } |
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Simmons, C., Walker, R., Perz, S., Aldrich, S., Caldas, M., Pereira, R., Leite, F., Fernandes, L.C. and Arima, E. | Doing it for Themselves: Direct Action Land Reform in the Brazilian Amazon | 2010 | World Development Vol. 38(3), pp. 429-444 |
article | DOI URL |
Abstract: The present paper considers a sometimes contentious process of land reform presently occurring in Brazil This process, referred to in the papers as Direct Action Land Reform (DALR), involves organizations such as the Landless Rural Workers Movement (Movimento dos Trabalhadores Rurans Sem Terra, or MST) and more spontaneous actions of individuals desiring a piece of land for their own Results of a survey covering 751 households engaged in such land reform actions in the Brazilian Amazon are presented, in order to describe participants and land reform process Evidently, social movement organizations provide for a modest degree of wealth accumulation, a welfare improvement that must be set against potential environmental costs The paper concludes by calling attention to the challenge DALR may ultimately pose to the Brazilian state. (C) 2009 Elsevier Ltd All rights reserved. | |||||
BibTeX:
@article{simmons_doing_2010, author = {Simmons, Cynthia and Walker, Robert and Perz, Stephen and Aldrich, Stephen and Caldas, Marcellus and Pereira, Ritaumaria and Leite, Flavia and Fernandes, Luiz Claudio and Arima, Eugenio}, title = {Doing it for Themselves: Direct Action Land Reform in the Brazilian Amazon}, journal = {World Development}, year = {2010}, volume = {38}, number = {3}, pages = {429--444}, url = {://WOS:000275354000017}, doi = {https://doi.org/10.1016/j.worlddev.2009.06.003} } |
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Silvestrini, R.A., Soares-Filho, B.S., Nepstad, D., Coe, M., Rodrigues, H. and Assuncao, R. | Simulating fire regimes in the Amazon in response to climate change and deforestation | 2011 | Ecological Applications Vol. 21(5), pp. 1573-1590 |
article | URL |
Abstract: Fires in tropical forests release globally significant amounts of carbon to the atmosphere and may increase in importance as a result of climate change. Despite the striking impacts of fire on tropical ecosystems, the paucity of robust spatial models of forest fire still hampers our ability to simulate tropical forest fire regimes today and in the future. Here we present a probabilistic model of human-induced fire occurrence for the Amazon that integrates the effects of a series of anthropogenic factors with climatic conditions described by vapor pressure deficit. The model was calibrated using NOAA-12 night satellite hot pixels for 2003 and validated for the years 2002, 2004, and 2005. Assessment of the fire risk map yielded fitness values textgreater85% for all months from 2002 to 2005. Simulated fires exhibited high overlap with NOAA-12 hot pixels regarding both spatial and temporal distributions, showing a spatial fit of 50% within a radius of 11 km and a maximum yearly frequency deviation of 15%. We applied this model to simulate fire regimes in the Amazon until 2050 using IPCC's A2 scenario climate data from the Hadley Centre model and a business-as-usual (BAU) scenario of deforestation and road expansion from SimAmazonia. Results show that the combination of these scenarios may double forest fire occurrence outside protected areas (PAs) in years of extreme drought, expanding the risk of fire even to the northwestern Amazon by midcentury. In particular, forest fires may increase substantially across southern and southwestern Amazon, especially along the highways slated for paving and in agricultural zones. Committed emissions from Amazon forest fires and deforestation under a scenario of global warming and uncurbed deforestation may amount to 21 +/- 4 Pg of carbon by 2050. BAU deforestation may increase fires occurrence outside PAs by 19% over the next four decades, while climate change alone may account for a 12% increase. In turn, the combination of climate change and deforestation would boost fire occurrence outside PAs by half during this period. Our modeling results, therefore, confirm the synergy between the two Ds of REDD (Reducing Emissions from Deforestation and Forest Degradation in Developing Countries). | |||||
BibTeX:
@article{silvestrini_simulating_2011, author = {Silvestrini, Rafaella Almeida and Soares-Filho, Britaldo Silveira and Nepstad, Daniel and Coe, Michael and Rodrigues, Hermann and Assuncao, Renato}, title = {Simulating fire regimes in the Amazon in response to climate change and deforestation}, journal = {Ecological Applications}, year = {2011}, volume = {21}, number = {5}, pages = {1573--1590}, note = {Edition: 2011/08/13}, url = {://WOS:000292766100012} } |
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Silver, W.L., Thompson, A.W., McGroddy, M.E., Varner, R.K., Dias, J.D., Silva, H., Crill, P.M. and Keller, M. | Fine root dynamics and trace gas fluxes in two lowland tropical forest soils | 2005 | Global Change Biology Vol. 11(2), pp. 290-306 |
article | DOI URL |
Abstract: Fine root dynamics have the potential to contribute significantly to ecosystem-scale biogeochemical cycling, including the production and emission of greenhouse gases. This is particularly true in tropical forests which are often characterized as having large fine root biomass and rapid rates of root production and decomposition. We examined patterns in fine root dynamics on two soil types in a lowland moist Amazonian forest, and determined the effect of root decay on rates of C and N trace gas fluxes. Root production averaged 229 (+/-35) and 153 (+/-27) g m(-2) yr(-1) for years 1 and 2 of the study, respectively, and did not vary significantly with soil texture. Root decay was sensitive to soil texture with faster rates in the clay soil (k=-0.96 year(-1)) than in the sandy loam soil (k=-0.61 year(-1)), leading to greater standing stocks of dead roots in the sandy loam. Rates of nitrous oxide (N2O) emissions were significantly greater in the clay soil (13+/-1 ng N cm(-2) h(-1)) than in the sandy loam (1.4+/-0.2 ng N cm(-2) h(-1)). Root mortality and decay following trenching doubled rates of N2O emissions in the clay and tripled them in sandy loam over a 1-year period. Trenching also increased nitric oxide fluxes, which were greater in the sandy loam than in the clay. We used trenching (clay only) and a mass balance approach to estimate the root contribution to soil respiration. In clay soil root respiration was 264-380 g C m(-2) yr(-1), accounting for 24% to 35% of the total soil CO2 efflux. Estimates were similar using both approaches. In sandy loam, root respiration rates were slightly higher and more variable (521+/-206 g C m(2) yr(-1)) and contributed 35% of the total soil respiration. Our results show that soil heterotrophs strongly dominate soil respiration in this forest, regardless of soil texture. Our results also suggest that fine root mortality and decomposition associated with disturbance and land-use change can contribute significantly to increased rates of nitrogen trace gas emissions. | |||||
BibTeX:
@article{silver_fine_2005, author = {Silver, W. L. and Thompson, A. W. and McGroddy, M. E. and Varner, R. K. and Dias, J. D. and Silva, H. and Crill, P. M. and Keller, M.}, title = {Fine root dynamics and trace gas fluxes in two lowland tropical forest soils}, journal = {Global Change Biology}, year = {2005}, volume = {11}, number = {2}, pages = {290--306}, url = {://WOS:000226705600010}, doi = {https://doi.org/10.1111/j.1365-2486.2005.00903.x} } |
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Silver, W.L., Neff, J., McGroddy, M., Veldkamp, E., Keller, M. and Cosme, R. | Effects of soil texture on belowground carbon and nutrient storage in a lowland Amazonian forest ecosystem | 2000 | Ecosystems Vol. 3(2), pp. 193-209 |
article | DOI URL |
Abstract: Soil texture plays a key role in belowground C storage in forest ecosystems and strongly influences nutrient availability and retention, particularly in highly weathered soils. We used field data and the Century ecosystem model to explore the role of soil texture in belowground C storage, nutrient pool sizes, and N fluxes in highly weathered soils in an Amazonian forest ecosystem. Our field results showed that sandy soils stored approximately 113 Mg C ha(-1) to a I-m depth versus 101 Mg C ha(-1) in clay soils. Coarse root C represented a large and significant ecosystem C pool, amounting to 62% and 48% of the surface soil C pool on sands and clays, respectively, and 34% and 22% of the soil C pool on sands and clays to l-m depth. The quantity of labile soil P, the soil C:N ratio, and live and dead fine root biomass in the 0-10-cm soil depth decreased along a gradient from sands to clays, whereas the opposite trend was observed for total P, mineral N, potential N mineralization. and denitrification enzyme activity. The Century model was able to predict the observed trends in surface soil C and N in loams and sands but underestimated C and N pools in the sands by approximately 45%. The model predicted that total belowground C (0-20 cm depth) in sands would be approximately half that of the clays, in contrast to the 89% we measured. This discrepancy is likely to be due to an underestimation of the role of belowground C allocation with low litter quality in sands, as well as an overestimation of the role of physical C protection by clays in this ecosystem. Changes in P and water availability had little effect on model outputs, whereas adding N greatly increased soil organic matter pools and productivity, illustrating the need for further integration of model structure and tropical forest biogeochemical cycling. | |||||
BibTeX:
@article{silver_effects_2000, author = {Silver, W. L. and Neff, J. and McGroddy, M. and Veldkamp, E. and Keller, M. and Cosme, R.}, title = {Effects of soil texture on belowground carbon and nutrient storage in a lowland Amazonian forest ecosystem}, journal = {Ecosystems}, year = {2000}, volume = {3}, number = {2}, pages = {193--209}, url = {://WOS:000087071600006}, doi = {https://doi.org/10.1007/s100210000019} } |
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Silver, W.L., Kueppers, L.M., Lugo, A.E., Ostertag, R. and Matzek, V. | Carbon sequestration and plant community dynamics following reforestation of tropical pasture | 2004 | Ecological Applications Vol. 14(4), pp. 1115-1127 |
article | DOI URL |
Abstract: Conversion of abandoned cattle pastures to secondary forests and plantations in the tropics has been proposed as a means to increase rates of carbon (C) sequestration from the atmosphere and enhance local biodiversity. We used a long-term tropical reforestation project (55-61 yr) to estimate rates of above- and belowground C sequestration and to investigate the impact of planted species on overall plant community structure. Thirteen tree species (nine native and four nonnative species) were planted as part of the reforestation effort in the mid to late 1930s. In 1992, there were 75 tree species (textgreater9.1 cm dbh) in the forest. Overall, planted species accounted for 40% of the importance value of the forest; planted normative species contributed only 5% of the importance value. In the reforested ecosystem, the total soil C pool (0-60 cm depth) was larger than the aboveground C pool, and there was more soil C in the forest (102 +/- 10 Mg/ha [mean +/- I SE]) than in an adjacent pasture of similar age (69 16 Mg/ha). Forest soil C (C-3-C) increased at a rate of similar to0.9 Mg(.)ha(-1.)yr(-1), but residual pasture C (C-4-C) was lost at a rate of 0.4 Mg(.)ha(-1.)yr(-1), yielding a net gain of 33 Mg/ha as a result of 61 years of forest regrowth. Aboveground C accumulated at a rate of 1.4 +/- 0.05 Mg(.)ha(-1.)yr(-1), to a total of 80 +/- 3 Mg/ha. A survey of 426 merchantable trees in 1959 and 1992 showed that they grew faster in the second 33 years of forest development than in the first 22 years, indicating that later stages of forest development can play an important role in C sequestration. Few indices of C cycling were correlated with plant community composition or structure. Our results indicate that significant soil C can accumulate with reforestation and that there are strong legacies of pasture use and reforestation in plant community structure and rates of plant C sequestration. | |||||
BibTeX:
@article{silver_carbon_2004, author = {Silver, W. L. and Kueppers, L. M. and Lugo, A. E. and Ostertag, R. and Matzek, V.}, title = {Carbon sequestration and plant community dynamics following reforestation of tropical pasture}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {1115--1127}, url = {://WOS:000223156600014 http://www.esajournals.org/doi/pdf/10.1890/03-5123}, doi = {https://doi.org/10.1890/03-5123} } |
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Silveira, J.M., Barlow, J., Krusche, A.V., Orwin, K.H., Balch, J.K. and Moutinho, P. | Effects of experimental fires on litter decomposition in a seasonally dry Amazonian forest | 2009 | Journal of Tropical Ecology Vol. 25, pp. 657-663 |
article | DOI URL |
Abstract: Litter decomposition is a fundamental process for nutrient cycling but we have a limited understanding of this process in disturbed tropical forests. We studied litter decomposition over a 10-mo period in a seasonally dry Amazon forest in Mato Grosso, Brazil. The study plots (50 ha each) included unburned forest (UF), once-burned (BF1) and forest burned annually for 3 y (BF3). We measured understorey density, litter depth, canopy openness. temperature and relative humidity in the plots. Decomposition experiments took place using 720 litterbags filled with approximately 10 g of natural abscised oven-dried leaves. To test the effects of tire on soil meso- and macrofauna, the litterbags had either a fine (2 mm) or coarse (with 1-cm holes in side) mesh size. Litterbags were collected and reweighed 2, 4, 6 and 8 mo after being placed on the forest floor. All forest structure variables were significantly different across plots: BF3 was hotter. less humid, had the highest degree of canopy openness, lowest understorey density and the shallowest litter depth. Litter decomposition (mass loss) was similar in the once-burned and unburned plots, but declined more slowly in BF3. In addition, decomposition was slower in fine-mesh litterbags than coarse-mesh litterbags in BF3. but there was no difference between mesh sizes in BF1 and UF. It is likely that changes in forest structure and microclimate explain the lower decomposition rates in BF3. These results show the importance of recurrent fires, but suggest that single understorey fires may not have long-term negative effects on some ecological processes in seasonally dry Amazonian forests. | |||||
BibTeX:
@article{silveira_effects_2009, author = {Silveira, Juliana M. and Barlow, Jos and Krusche, Alex V. and Orwin, Kate H. and Balch, Jennifer K. and Moutinho, Paulo}, title = {Effects of experimental fires on litter decomposition in a seasonally dry Amazonian forest}, journal = {Journal of Tropical Ecology}, year = {2009}, volume = {25}, pages = {657--663}, url = {://WOS:000271315100009}, doi = {https://doi.org/10.1017/s0266467409990150} } |
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Silva-Dias, M.A.F., Silva-Dias, P.L., Longo, M., Fitzjarrald, D.R. and Denning, A.S. | River breeze circulation in eastern Amazonia: observations and modelling results | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 111-121 |
article | DOI URL |
Abstract: The CIRSAN/LBA field campaign was conducted close to two major rivers of the Amazon Basin, the Tapajos and the Amazon. The observations indicate that during weak trade wind episodes the Tapajos River breeze actually induces a westerly flow at the eastern margin with an associated line of shallow cumulus. The atmospheric circulation induced by the river has been interpreted with the help of a high resolution numerical simulation. A single cell forms during late morning over the Tapajos River and evolves into the afternoon with ascending motion in the eastern margin and a descending branch in the western margin suppressing cloud formation. During the night, convergence is seen along the centre of the River Tapajos. The implications of the particular geometry of the river with respect to the trade winds for the generalization of the surface measurements of turbulent fluxes of heat, moisture and CO2 in the Tapajos eastern margin of the Amazon Basin as a whole are discussed. | |||||
BibTeX:
@article{silva-dias_river_2004, author = {Silva-Dias, M. A. F. and Silva-Dias, P. L. and Longo, M. and Fitzjarrald, D. R. and Denning, A. S.}, title = {River breeze circulation in eastern Amazonia: observations and modelling results}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {111--121}, url = {://WOS:000222024700009}, doi = {https://doi.org/10.1007/s00704-004-0047-6} } |
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Silva-Dias, M.A.F., Rutledge, S., Kabat, P., Silva-Dias, P.L., Nobre, C., Fisch, G., Dolman, A.J., Zipser, E., Garstang, M., Manzi, A.O., Fuentes, J.D., Rocha, H.R., Marengo, J., Plana-Fattori, A., Sa, L.D.A., Alvala, R.C.S., Andreae, M.O., Artaxo, P., Gielow, R. and Gatti, L. | Cloud and rain processes in a biosphere-atmosphere interaction context in the Amazon Region | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: This paper presents an overview of the results from the first major mesoscale atmospheric campaign of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) Program. The campaign, collocated with a Tropical Rainfall Measuring Mission (TRMM) satellite validation campaigns, was conducted in southwest Rondonia in January and February 1999 during the wet season. Highlights on the interaction between clouds, rain, and the underlying landscape through biospheric processes are presented and discussed. | |||||
BibTeX:
@article{silva-dias_cloud_2002, author = {Silva-Dias, M. A. F. and Rutledge, S. and Kabat, P. and Silva-Dias, P. L. and Nobre, C. and Fisch, G. and Dolman, A. J. and Zipser, E. and Garstang, M. and Manzi, A. O. and Fuentes, J. D. and Rocha, H. R. and Marengo, J. and Plana-Fattori, A. and Sa, L. D. A. and Alvala, R. C. S. and Andreae, M. O. and Artaxo, P. and Gielow, R. and Gatti, L.}, title = {Cloud and rain processes in a biosphere-atmosphere interaction context in the Amazon Region}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200028 http://www.agu.org/journals/jd/jd0217/2001JD000335/2001JD000335.pdf}, doi = {https://doi.org/10.1029/2001jd000335} } |
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Silva-Dias, M.A.F., Petersen, W., Silva-Dias, P.L., Cifelli, R., Betts, A.K., Longo, M., Gomes, A.M., Fisch, G.F., Lima, M.A., Antonio, M.A. and Albrecht, R.I. | A case study of convective organization into precipitating lines in the Southwest Amazon during the WETAMC and TRMM-LBA | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: A case study of convective development in the Southwest Amazon region during the Wet Season Atmospheric Mesoscale Campaign (WETAMC) and Tropical Rainfall Measuring Mission (TRMM)/Large-Scale Biosphere-Atmosphere (LBA) Experiment in Amazonia is presented. The convective development during 7 February 1999 is shown to occur during a period of very weak large-scale forcing in the presence of topography and deforestation. The available data include dual Doppler radar analysis, radiosonde launches, and surface and boundary layer observations. The observational analysis is complemented with a series of model simulations using the RAMS with 2-km resolution over a 300 km 300 km area forced by a morning radiosonde profile. A comparison of the observed and simulated thermodynamic transformation of the boundary layer and of the formation of convective lines, and of their kinematic and microphysical properties is presented. It is shown that only a few very deep and intense convective cells are necessary to explain the overall precipitating line formation and that discrete propagation and coupling with upper atmosphere circulations may explain the appearance of several lines. The numerical simulation indicates that topography may be the cause of initial convective development, although later on the convective line is parallel to the midlevel shear. There are indications that small-scale deforestation may have an effect on increasing rainfall in the wet season when the large-scale forcing is very weak. | |||||
BibTeX:
@article{silva-dias_case_2002, author = {Silva-Dias, M. A. F. and Petersen, W. and Silva-Dias, P. L. and Cifelli, R. and Betts, A. K. and Longo, M. and Gomes, A. M. and Fisch, G. F. and Lima, M. A. and Antonio, M. A. and Albrecht, R. I.}, title = {A case study of convective organization into precipitating lines in the Southwest Amazon during the WETAMC and TRMM-LBA}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200046 http://www.agu.org/journals/jd/jd0218/2001JD000375/2001JD000375.pdf}, doi = {https://doi.org/10.1029/2001jd000375} } |
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Silva-Dias, M. | Meteorologia , desmatamento e queimadas na Amazônia: uma síntese de resultados do LBA [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 190-199 |
article | |
BibTeX:
@article{silva-dias_meteorologia_2006, author = {Silva-Dias, M.A.F.}, title = {Meteorologia , desmatamento e queimadas na Amazônia: uma síntese de resultados do LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {190--199} } |
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Silva-Dias, C., J.C.P., G. and M.A.F., A.W. | Interações entre nuvens, chuvas e a biosfera na Amazônia [BibTeX] |
2005 | Acta Amazonica Vol. 35(2), pp. 215-222 |
article | |
BibTeX:
@article{silva-dias_interacoes_2005, author = {Silva-Dias, Cohen, J.C.P., Gandú, A.W., M.A.F.}, title = {Interações entre nuvens, chuvas e a biosfera na Amazônia}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, number = {2}, pages = {215--222} } |
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Silva, V., Almeida, R., Singh, V., Chagas, G., Dantas, V. and Costa, A. | Aboveground Biomass Dynamics in the Amazonian Rainforest under Influence of Reduction in Rainfall [BibTeX] |
2012 | Journal of Forestry Research Vol. 1, pp. 1-6 |
article | |
BibTeX:
@article{silva_aboveground_2012, author = {Silva, V.P.R. and Almeida, R.S.R. and Singh, V.P. and Chagas, G.F.B. and Dantas, V.A. and Costa, A.C.L.}, title = {Aboveground Biomass Dynamics in the Amazonian Rainforest under Influence of Reduction in Rainfall}, journal = {Journal of Forestry Research}, year = {2012}, volume = {1}, pages = {1--6} } |
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Silva, T.S.F., Costa, M.P.F., Melack, J.M. and Novo, E.M.L.M. | Remote sensing of aquatic vegetation: theory and applications | 2008 | Environmental Monitoring and Assessment Vol. 140(1-3), pp. 131-145 |
article | DOI URL |
Abstract: Aquatic vegetation is an important component of wetland and coastal ecosystems, playing a key role in the ecological functions of these environments. Surveys of macrophyte communities are commonly hindered by logistic problems, and remote sensing represents a powerful alternative, allowing comprehensive assessment and monitoring. Also, many vegetation characteristics can be estimated from reflectance measurements, such as species composition, vegetation structure, biomass, and plant physiological parameters. However, proper use of these methods requires an understanding of the physical processes behind the interaction between electromagnetic radiation and vegetation, and remote sensing of aquatic plants have some particular difficulties that have to be properly addressed in order to obtain successful results. The present paper reviews the theoretical background and possible applications of remote sensing techniques to the study of aquatic vegetation. | |||||
BibTeX:
@article{silva_remote_2008, author = {Silva, Thiago S. F. and Costa, Maycira P. F. and Melack, John M. and Novo, Evlyn M. L. M.}, title = {Remote sensing of aquatic vegetation: theory and applications}, journal = {Environmental Monitoring and Assessment}, year = {2008}, volume = {140}, number = {1-3}, pages = {131--145}, note = {Edition: 2007/06/27}, url = {://WOS:000254434400013}, doi = {https://doi.org/10.1007/s10661-007-9855-3} } |
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Silva, T.S.F., Costa, M.P.F. and Melack, J.M. | Spatial and temporal variability of macrophyte cover and productivity in the eastern Amazon floodplain: A remote sensing approach | 2010 | Remote Sensing of Environment Vol. 114(9), pp. 1998-2010 |
article | DOI URL |
Abstract: Herbaceous aquatic macrophytes cover extensive areas on the floodplains of the Amazon basin and are an important habitat and input of organic carbon. These communities have large intra- and inter-annual variability, and characterization of this variability is necessary to quantify the role of macrophytes in the ecology and biogeochemistry of the floodplain. A novel approach for mapping the temporal evolution of aquatic vegetation in the Amazon floodplain, which could be adapted to other spatially and temporally changing environments, is presented Macrophyte cover varied seasonally and Inter-annually, ranging between 104 and 198 km(2) for the floodplain examined (total area, 984 km(2)). The observed evolution of plant distribution indicated a spatial and temporal partition of macrophyte communities into short-lived and annual groups. A simulation of macrophyte net primary production (NPP) based on the mapping results indicated that at least 3% of NPP could be attributed to the short-lived communities. The present results suggest that significant changes in the macrophyte's contribution to carbon cycling in the Amazon floodplain could occur as a result of the predicted increase in frequency of drought years for the Amazon system due to climate change. (C) 2010 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{silva_spatial_2010, author = {Silva, Thiago Sanna F. and Costa, Maycira P. F. and Melack, John M.}, title = {Spatial and temporal variability of macrophyte cover and productivity in the eastern Amazon floodplain: A remote sensing approach}, journal = {Remote Sensing of Environment}, year = {2010}, volume = {114}, number = {9}, pages = {1998--2010}, url = {://WOS:000279495200010}, doi = {https://doi.org/10.1016/j.rse.2010.04.007} } |
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Silva, T.S.F., Costa, M.P.F. and Melack, J.M. | Assessment of two biomass estimation methods for aquatic vegetation growing on the Amazon Floodplain | 2010 | Aquatic Botany Vol. 92(3), pp. 161-167 |
article | DOI URL |
Abstract: Studies of macrophyte productivity in the Amazon region are limited by accessibility and costs; hence, they may suffer from reduced sample size and representation. The present study compares a phenometric (indirect) method and a subsampling(direct) method in terms of accuracy and applicability to estimation of aquatic macrophyte biomass in the Amazon. The results show that phenometric models were not as effective as selective subsampling for the estimation of macrophyte biomass under the studied conditions. Phenometric models performed more acceptably for predicting emergent biomass, and less for submerged and total biomass (r(2) = 0.77, p textless 0.05, RMSE = 200-600 g/m(2) dry mass). Improvements in r(2) by using species-specific phenometric models were mostly not significant. Phenotypic variation across the studied region was large enough to preclude the generalization of phenometric relationships into accurate numeric models, while the direct subsampling method was able to account for this variation (RMSE textless 500 g/m(2) dry mass). Subsampling also allowed a significant reduction on the physical effort of biomass sampling, which directly translated into wider and more complete sampling. We suggest that direct subsampling presents the best trade-off between accuracy and coverage for macrophyte biomass measurement in the Amazon floodplain. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{silva_assessment_2010, author = {Silva, Thiago Sanna F. and Costa, Maycira P. F. and Melack, John M.}, title = {Assessment of two biomass estimation methods for aquatic vegetation growing on the Amazon Floodplain}, journal = {Aquatic Botany}, year = {2010}, volume = {92}, number = {3}, pages = {161--167}, url = {://WOS:000275214400001}, doi = {https://doi.org/10.1016/j.aquabot.2009.10.015} } |
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Silva, T.S.F., Costa, M.P.F. and Melack, J.M. | Annual net primary production of macrophytes in the eastern Amazon floodplain | 2009 | Wetlands Vol. 29(2), pp. 747-758 |
article | URL |
Abstract: Aquatic herbaceous macrophytes contribute significantly to the input carbon for the Amazon floodplain. These plants have large seasonal variations in areal coverage and high productivity. The present study estimates annual net primary production (NPP) of aquatic herbaceous macrophytes in a large lake on the eastern Amazon floodplain, assesses the sources and amount of uncertainty associated with these measures, and offers a comparison among the estimates of herbaceous macrophyte productivity in the Amazon region. Plant biomass accumulated during the rising water stage of the annual flood cycle, peaking at 2300 to 6100 g m(-2) and decreasing later in the year. Annual net primary production was estimated to range from 2400 to 3500 g m(-2) yr(-1), with above water production between 650 and 1100 g m(-2) yr(-1), and below water production between 1700 and 2600 g m(-2) yr(-1). Echinochloa polystachya and Paspalum fasciculatum were the most productive species, followed by Paspalum repens, Hymenachne amplexicaulis, and Oryza perennis. The four main sources of uncertainty in the estimates were macrophyte taxa, location, sampling design, and lack of measurements of dead material loss. | |||||
BibTeX:
@article{silva_annual_2009, author = {Silva, Thiago S. F. and Costa, Maycira P. F. and Melack, John M.}, title = {Annual net primary production of macrophytes in the eastern Amazon floodplain}, journal = {Wetlands}, year = {2009}, volume = {29}, number = {2}, pages = {747--758}, url = {://WOS:000268987300032} } |
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Silva, R.R.d., Werth, D. and Avissar, R. | Regional impacts of future land-cover changes on the amazon basin wet-season climate | 2008 | Journal of Climate Vol. 21(6), pp. 1153-1170 |
article | DOI URL |
Abstract: State-of-the-art socioeconomic scenarios of land-cover change in the Amazon basin for the years 2030 and 2050 are used together with the Regional Atmospheric Modeling System (RAMS) to simulate the hydrometeorological changes caused by deforestation in that region under diverse climatological conditions that include both El Nino and La Nina events. The basin-averaged rainfall progressively decreases with the increase of deforestation from 2000 to 2030, 2050, and so on, to total deforestation by the end of the twenty-first century. Furthermore, the spatial distribution of rainfall is significantly affected by both the land-cover type and topography. While the massively deforested region experiences an important decrease of precipitation, the areas at the edge of that region and at elevated regions receive more rainfall. Propagating squall lines over the massively deforested region dissipate before reaching the western part of the basin, causing a significant decrease of rainfall that could result in a catastrophic collapse of the ecosystem in that region. The basin experiences much stronger precipitation changes during El Niho events as deforestation increases. During these periods, deforestation in the western part of the basin induces a very significant decrease of precipitation. During wet years, however, deforestation has a minor overall impact on the basin climatology. | |||||
BibTeX:
@article{silva_regional_2008, author = {Silva, Renato Ramos da and Werth, David and Avissar, Roni}, title = {Regional impacts of future land-cover changes on the amazon basin wet-season climate}, journal = {Journal of Climate}, year = {2008}, volume = {21}, number = {6}, pages = {1153--1170}, url = {://WOS:000254421100001}, doi = {https://doi.org/10.1175/2007jcli1304.1} } |
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Silva, R.R.d., Bohrer, G., Werth, D., Otte, M.J. and Avissar, R. | Sensitivity of ice storms in the southeastern United States to Atlantic SST - Insights from a case study of the December 2002 storm | 2006 | Monthly Weather Review Vol. 134(5), pp. 1454-1464 |
article | URL |
Abstract: Meteorological observations and model simulations are used to show that the catastrophic ice storm of 4-5 December 2002 in the southeastern United States resulted from the combination of a classic winter storm and a warm sea surface temperature (SST) anomaly in the western Atlantic Ocean. At the time of the storm, observations show that the Atlantic SST near the southeastern U.S. coast was 1.0 degrees-1.5 degrees C warmer than its multiyear mean. The impact of this anomalous SST on the ice accumulation of the ice storm was evaluated with the Regional Atmospheric Modeling System. The model shows that a warmer ocean leads to the conversion of more snow into freezing rain while not significantly affecting the inland surface temperature. Conversely a cooler ocean produces mostly snowfall and less freezing rain. A similar trend is obtained by statistically comparing observations of ice storms in the last decade with weekly mean Atlantic SSTs. The SST during an ice storm is significantly and positively correlated with a deeper and warmer melting layer. | |||||
BibTeX:
@article{silva_sensitivity_2006, author = {Silva, Renato Ramos da and Bohrer, Gil and Werth, David and Otte, Martin J. and Avissar, Roni}, title = {Sensitivity of ice storms in the southeastern United States to Atlantic SST - Insights from a case study of the December 2002 storm}, journal = {Monthly Weather Review}, year = {2006}, volume = {134}, number = {5}, pages = {1454--1464}, url = {://WOS:000237559200008} } |
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Silva, R.R.d. and Avissar, R. | The hydrometeorology of a deforested region of the Amazon basin | 2006 | Journal of Hydrometeorology Vol. 7(5), pp. 1028-1042 |
article | URL |
Abstract: A series of numerical simulations were performed to evaluate the capability of the Regional Atmospheric Modeling System (RAMS) to simulate the evolution of convection in a partly deforested region of the Amazon basin during the rainy season, and to elucidate some of the complex land-atmosphere interactions taking place in that region. Overall, it is demonstrated that RAMS can simulate properly the domain-average accumulated rainfall in Rondonia, Brazil, when provided with reliable initial profiles of atmospheric relative humidity and soil moisture. It is also capable of simulating important feedbacks involving the energy partition at the ground surface and the formation of convection. In general, more water in the soil and/or the atmosphere produces more rainfall. However, these conditions affect the onset of rainfall in opposite ways; while higher atmospheric relative humidity leads to early rainfall, higher soil moisture delays its formation. As compared to stratiform clouds, which tend to cover a large area, convective clouds are localized and they let relatively more solar radiation reach the ground surface. As a result, a stronger sensible heat flux is released at the ground surface, which enhances the atmospheric instability and reinforces convection. Simulations using horizontal grid elements 2 and 4 km in size show a delay and decrease of rainfall as compared to simulations with high-resolution grids whose elements are not larger than 1 km and, as a result, afflict RAMS performance. It is concluded that RAMS can be used as a reliable tool to simulate the various hydrometeorological processes involved in land-cover changes as a result of deforestation in this region. | |||||
BibTeX:
@article{silva_hydrometeorology_2006, author = {Silva, Renato Ramos da and Avissar, Roni}, title = {The hydrometeorology of a deforested region of the Amazon basin}, journal = {Journal of Hydrometeorology}, year = {2006}, volume = {7}, number = {5}, pages = {1028--1042}, url = {://WOS:000241755800013} } |
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Silva, R.R., Gandu, A.W., Sa, L.D.A. and Silva Dias, M.A.F. | Cloud streets and land-water interactions in the Amazon | 2011 | Biogeochemistry Vol. 105(1-3), pp. 201-211 |
article | DOI URL |
Abstract: Cloud streets are common feature in the Amazon Basin. They form from the combination of the vertical trade wind stress and moist convection. Here, satellite imagery, data collected during the COBRA-PARA (Caxiuan Observations in the Biosphere, River and Atmosphere of Para) field campaign, and high resolution modeling are used to understand the streets' formation and behavior. The observations show that the streets have an aspect ratio of about 3.5 and they reach their maximum activity around 15:00 UTC when the wind shear is weaker, and the convective boundary layer reaches its maximum height. The simulations reveal that the cloud streets onset is caused by the local circulations and convection produced at the interfaces between forest and rivers of the Amazon. The satellite data and modeling show that the large rivers anchor the cloud streets producing a quasi-stationary horizontal pattern. The streets are associated with horizontal roll vortices parallel to the mean flow that organizes the turbulence causing advection of latent heat flux towards the upward branches. The streets have multiple warm plumes that promote a connection between the rolls. These spatial patterns allow fundamental insights on the interpretation of the Amazon exchanges between surface and atmosphere with important consequences for the climate change understanding. | |||||
BibTeX:
@article{silva_cloud_2011, author = {Silva, Renato Ramos and Gandu, Adilson W. and Sa, Leonardo D. A. and Silva Dias, Maria A. F.}, title = {Cloud streets and land-water interactions in the Amazon}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {201--211}, url = {://WOS:000294501100015 http://www.springerlink.com/content/r1w680q042x7l313/fulltext.pdf}, doi = {https://doi.org/10.1007/s10533-011-9580-4} } |
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Silva, R.P., dos Santos, J., Tribuzy, E.S., Chambers, J.Q., Nakamura, S. and Higuchi, N. | Diameter increment and growth patterns for individual tree growing in Central Amazon, Brazil | 2002 | Forest Ecology and Management Vol. 166(1-3), pp. 295-301 |
article | DOI URL |
Abstract: Information on diameter increment and growth patterns for individual trees are important tools for forest management primarily to: (i) select tree species for logging; (ii) selecting tree species for protection; (iii) estimate cutting cycles and (iv) to prescribe silvicultural treatments. Most growth and yield studies in tropical moist forests have emphasized only the stand level instead of individual trees. This study dealt with the analysis of individual growth patterns for 272 trees distributed over two transects (East-West and North-South) measuring 20 m x 2500 m, which were stratified by plateau, slope and "baixio" (lowland areas near small streams), and tree diameter at breast height (DBH) classes (10 cm less than or equal to DBH textless 30 cm, 30 cm less than or equal to DBH textless 50 cm and DBH greater than or equal to 50 cm). For each tree, a metal "dendrometer" band was fixed to the trunk and growth in circumference was measured with digital calipers. Measurements were carried out for 19 months, from June 1999 to December 2000; for this study, only 12 months of year 2000 were considered. Individual growth pattern varied significantly over time (P = 0.00), and slightly (P = 0.08) when the interaction months and DBH classes was included; on the other hand, the signal was very weak (P = 0.25) when topographical classes were added to the later interaction, and no signal at all (P = 0.89) when the interaction between months, diameter and topographical classes were analyzed. Mean annual diameter increment considering all 272 monitored trees was 1.64 +/- 0.21 mm per year (95% CI), falling within the range estimated for the Brazilian Amazon region (1.4-2 mm per year). (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{silva_diameter_2002, author = {Silva, R. P. and dos Santos, J. and Tribuzy, E. S. and Chambers, J. Q. and Nakamura, S. and Higuchi, N.}, title = {Diameter increment and growth patterns for individual tree growing in Central Amazon, Brazil}, journal = {Forest Ecology and Management}, year = {2002}, volume = {166}, number = {1-3}, pages = {295--301}, url = {://WOS:000177023600022}, doi = {https://doi.org/10.1016/s0378-1127(01)00678-8} } |
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Silva, N., Azevedo, S., Chambers, C.P., Rocha, J., Pinto, R.M., A.C.M., S., Higuchi, J. and R.P., N. | Uso de banda dendrométrica na definição de padrões de crescimento individual em diâmetro de árvores da bacia do Rio Cuieiras [BibTeX] |
2003 | Acta Amazonica Vol. 33(1), pp. 67-84 |
article | |
BibTeX:
@article{silva_uso_2003, author = {Silva, Nakamura, S., Azevedo, C.P., Chambers, J., Rocha, R.M., Pinto, A.C.M., Santos, J., Higuchi, N., R.P.}, title = {Uso de banda dendrométrica na definição de padrões de crescimento individual em diâmetro de árvores da bacia do Rio Cuieiras}, journal = {Acta Amazonica}, year = {2003}, volume = {33}, number = {1}, pages = {67--84} } |
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Silva, C., J.M.N. da, R., da Costa, M.L., A.C.L., A. and R.M. da, S.S. | Influência de variáveis meteorológicas na produção de liteira na Estação Científica Ferreira Penna, Caxiuanã, Pará [BibTeX] |
2009 | Acta Amazonica Vol. 39(3), pp. 561 - 570 |
article | |
BibTeX:
@article{silva_influencia_2009, author = {Silva, Costa, J.M.N. da, Ruivo, M.L., da Costa, A.C.L., Almeida, S.S., R.M. da}, title = {Influência de variáveis meteorológicas na produção de liteira na Estação Científica Ferreira Penna, Caxiuanã, Pará}, journal = {Acta Amazonica}, year = {2009}, volume = {39}, number = {3}, pages = {561 -- 570} } |
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Silva, R.B.d. and Gonçalves, F.L. | Statistical influence of climate on the population density of culex and coquillettidia mosquitoes [BibTeX] |
2022 | Int J Hydro. Vol. 6(5), pp. 188-195 |
article | |
BibTeX:
@article{silva_statistical_2022, author = {Silva, Rommel BC da and Gonçalves, Fábio LT}, title = {Statistical influence of climate on the population density of culex and coquillettidia mosquitoes}, journal = {Int J Hydro.}, year = {2022}, volume = {6}, number = {5}, pages = {188--195} } |
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Silva, R.B.C.d., Sá, L.D.A., Barreto, P.N., Nunes, H.G.G.C., Rodrigues, R.S., Rodrigues, H.J.B. and Silva, R.M.d. | Análise da variação do nível de fração evaporativa na Floresta Nacional de Caxiuanã [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 137-140 |
article | |
BibTeX:
@article{silva_alise_2009, author = {Silva, Rommel B. C. da and Sá, Leonardo D. A. and Barreto, Priscilla N. and Nunes, Hildo G. G. C. and Rodrigues, Ronaldo S. and Rodrigues, Hernani J. B. and Silva, Rosecélia M. da}, title = {Análise da variação do nível de fração evaporativa na Floresta Nacional de Caxiuanã}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {137--140} } |
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Silva Silva, R.C.J.C.A.R. | Eficiência de uso da água e da radiação em um ecossistema de manguezal no Estado do Pará [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 104-116 |
article | |
BibTeX:
@article{silva_eficiencia_2006, author = {Silva, Silva, R.M. Costa, J.M.N., Costa, A.C.L., R.B.C.}, title = {Eficiência de uso da água e da radiação em um ecossistema de manguezal no Estado do Pará}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {104--116} } |
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Silva, P.R.S., Rosa, A.M., Hacon, S.S. and Ignotti, E. | Hospitalization of children for asthma in the Brazilian Amazon: trend and spatial distribution | 2009 | Jornal De Pediatria Vol. 85(6), pp. 541-546 |
article | DOI URL |
Abstract: Objective: To analyze the distribution of hospitalizations of children for asthma in the states comprising the Brazilian Amazon, as well as the variations of hospitalization according to climatic seasonality. Methods: A descriptive study of the distribution of hospitalizations for asthma of individuals aged 0 to 14 years living in the Brazilian Amazon, according to trend, spatial distribution, and climatic seasonality over the period from 2001 to 2007. We used the database of authorizations for hospitalizations (AIH) of the Hospital Information System (SIH/SUS) of the Brazilian Ministry of Health. Results: The spatial distribution of hospitalizations for asthma resembles the configuration of the "arc of deforestation," mainly in the states of Rondonia and Maranhao. The distribution of annual hospitalizations for asthma decreased from 8.1 to 2.6 hospitalizations/1,000 inhabitants during the period. There was a peak of hospitalizations in March and May in all states. The seasonal differences were on average 10%, with the highest rates during the rainy season. Conclusion: We concluded that hospitalizations for asthma are more frequent in the months of more intense rainfall, with greater magnitude in the states comprising the "arc of deforestation" in the Brazilian Amazon, especially Rondonia and Maranhao. | |||||
BibTeX:
@article{silva_hospitalization_2009, author = {Silva, Pamela R. S. and Rosa, Antonio M. and Hacon, Sandra S. and Ignotti, Eliane}, title = {Hospitalization of children for asthma in the Brazilian Amazon: trend and spatial distribution}, journal = {Jornal De Pediatria}, year = {2009}, volume = {85}, number = {6}, pages = {541--546}, url = {://WOS:000273750100012}, doi = {https://doi.org/10.2223/jped.1952} } |
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Silva, P., Rodrigues, P., Ignotti, E., Rosa, A. and Hacon, S. | Hospitalization of Children for Asthma in the Brazilian Amazon: Trend and Spatial Distribution [BibTeX] |
2011 | Epidemiology Vol. 22(1), pp. S169-S169 |
article | DOI URL |
BibTeX:
@article{silva_hospitalization_2011, author = {Silva, Pamela and Rodrigues, Poliany and Ignotti, Eliane and Rosa, Antonia and Hacon, Sandra}, title = {Hospitalization of Children for Asthma in the Brazilian Amazon: Trend and Spatial Distribution}, journal = {Epidemiology}, year = {2011}, volume = {22}, number = {1}, pages = {S169--S169}, url = {://WOS:000285400800501}, doi = {https://doi.org/10.1097/01.ede.0000392193.65028.a6} } |
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Silva, M.V., Santana, R., Vale, R., Tóta, J. and Fitzjarrald, D. | Análise do perfil vertical de CO2 em uma área de floresta na Amazônia central [BibTeX] |
2015 | Revista Ciência e Natura Vol. 37 Edição Esp.(V Simpósio Internacional de Climatologia), pp. 22-26 |
article | DOI |
BibTeX:
@article{silva_alise_2015, author = {Silva, M. V. and Santana, R.A.S. and Vale, R.S.V. and Tóta, J. and Fitzjarrald, D.R}, title = {Análise do perfil vertical de CO2 em uma área de floresta na Amazônia central}, journal = {Revista Ciência e Natura}, year = {2015}, volume = {37 Edição Esp.}, number = {V Simpósio Internacional de Climatologia}, pages = {22--26}, doi = {https://doi.org/10.5902/2179460X16210} } |
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Silva, M.T.d., Barbosa, H.d.M.J. and Pauliquevis Júnior, T.M. | Thermodynamic indexes during the GOAmazon2014/5 campaign and comparison with ERA-Interim reanalysis data | 8 | Ciência e Natura Vol. 42(0), pp. e19 |
article | DOI URL |
Abstract: <p>The thermodynamic indexes LCL, LFC, CINE and CAPE characterize atmospheric instability, and allow the study of cloud formation and convection, important phenomena for the hydrologic cycle and the radiative balance. For this reason, this work makes a seasonal analysis of these thermodynamic indexes computed from radiosondes released during the GOAmazon2014/5 experiment. A comparison was made with ERA-Interim reanalysis for both these indexes and the temperature and relative humidity profiles. Analysis of radiosonde data shows that the median vertical profile of relative humidity in the dry season was lower in 2015 when compared to 2014, resulting in higher LCL (textasciitilde50 hPa at 18 Z) and lower CAPE (textasciitilde50% lower). The difference stems from a more severe dry season in 2015 when compared with 2014. The comparison with the reanalysis reveals that modeled LCL values are only compatible with observed ones at 18 Z (mean bias -10 hPa). On the other hand, CAPE values are always incompatible (mean bias -750 j/kg). Results indicate that ERA Interim poorly represents the thermodynamic conditions over the Amazon rainforest.</p> | |||||
BibTeX:
@article{silva_thermodynamic_8, author = {Silva, Matheus Tolentino da and Barbosa, Henrique de Melo Jorge and Pauliquevis Júnior, Theotonio Mendes}, title = {Thermodynamic indexes during the GOAmazon2014/5 campaign and comparison with ERA-Interim reanalysis data}, journal = {Ciência e Natura}, year = {8}, volume = {42}, number = {0}, pages = {e19}, note = {Section: SPECIAL EDITION}, url = {https://periodicos.ufsm.br/cienciaenatura/article/view/46842}, doi = {https://doi.org/10.5902/2179460X46842} } |
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Silva, M.P.R., Goncalves, F.L.T. and Freitas, S.R. | Two case studies of sulfate scavenging processes in the Amazon region (Rondonia) | 2009 | Environmental Pollution Vol. 157(2), pp. 637-645 |
article | DOI URL |
Abstract: The scavenging processes of chemical species have been previously studied with numerical modeling, in order to understand the gas and particulate matter intra-reservoir transferences. In this study, the atmospheric (RAMS) and scavenging (B.V.2) models were used, in order to simulate sulfate concentrations in rainwater using scavenging processes as well as the local atmospheric conditions obtained within the LBA Project in the State of Rondonia, during a dry-to-wet transition season. Two case studies were conducted. The RAMS atmospheric simulation of these events presented satisfactory results, showing the detailed microphysical processes of clouds in the Amazonian region. On the other hand, with cloud entrainments, observed values have been overestimated. Modeled sulfate rainwater concentration, using exponential decay and cloud heights of 16 km and no entrainments, presented the best results, reaching 97% of the observed value. The results, using shape parameter 5, are the best, improving the overall result. (C) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{silva_two_2009, author = {Silva, M. P. R. and Goncalves, F. L. T. and Freitas, S. R.}, title = {Two case studies of sulfate scavenging processes in the Amazon region (Rondonia)}, journal = {Environmental Pollution}, year = {2009}, volume = {157}, number = {2}, pages = {637--645}, note = {Edition: 2008/10/15}, url = {://WOS:000262971900037}, doi = {https://doi.org/10.1016/j.envpol.2008.08.016} } |
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Silva, L.M.d., Sá, L.D.d.A. and Mota, M.A.S.d. | Avaliação das características dos regimes diurnos de umidade em áreas de floresta e savana tropicais [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 85-88 |
article | |
BibTeX:
@article{silva_avaliacao_2009, author = {Silva, Ludmila Monteiro da and Sá, Leonardo Deane de Abreu and Mota, Maria Aurora Santos da}, title = {Avaliação das características dos regimes diurnos de umidade em áreas de floresta e savana tropicais}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {85--88} } |
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Silva, L., Sá, L. and Mota, M. | Avaliação de características dos regimes de umidade na flona de Caxiuanã-PA durante o experimento COBRA-PARÁ [BibTeX] |
2010 | Revista Brasileira de Meteorologia Vol. 25, pp. 1-12 |
article | |
BibTeX:
@article{silva_avaliacao_2010, author = {Silva, L.M. and Sá, L.D.A. and Mota, M.A.S.}, title = {Avaliação de características dos regimes de umidade na flona de Caxiuanã-PA durante o experimento COBRA-PARÁ}, journal = {Revista Brasileira de Meteorologia}, year = {2010}, volume = {25}, pages = {1--12} } |
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Silva Júnior, J.d.A., da Costa, A.C.L., De Azevedo, P.V., Da Costa, R.F., Metcalfe, D.B., Gonçalves, P.H.L., Braga, A.P., Malhi, Y.S., Aragão, L.E.O.E.C.d. and Meir, P. | Fluxos de CO2 do Solo Na Floresta Nacional de Caxiuanã, Pará, durante o Experimento ESECAFLOR/LBA [BibTeX] |
2013 | Revista Brasileira de Meteorologia Vol. 28(1), pp. 85 - 94 |
article | |
BibTeX:
@article{silva_junior_fluxos_2013, author = {Silva Júnior, João de Athaydes and da Costa, Antonio Carlos Lôla and De Azevedo, Pedro Vieira and Da Costa, Rafael Ferreira and Metcalfe, Daniel B. and Gonçalves, Paulo Henrique Lopes and Braga, Alan Pantoja and Malhi, Yadvinder S. and Aragão, Luiz Eduardo O. E C. de and Meir, Patrick}, title = {Fluxos de CO2 do Solo Na Floresta Nacional de Caxiuanã, Pará, durante o Experimento ESECAFLOR/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2013}, volume = {28}, number = {1}, pages = {85 -- 94} } |
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Silva Júnior, C., Braga, R.F., Costa, A.P., A.C.L., G., P.H.L., M., Aragão, Y.S., L.E.O.E.C., M. and J.A., P. | Sazonalidade de elementos meteorológicos em ecossistema de manguezal na região equatorial, Pará, Brasil [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 241-247 |
article | |
BibTeX:
@article{silva_junior_sazonalidade_2006, author = {Silva Júnior, Costa, R.F., Braga, A.P., Costa, A.C.L., Gonçalves, P.H.L., Malhi, Y.S., Aragão, L.E.O.E.C., Meir, P., J.A.}, title = {Sazonalidade de elementos meteorológicos em ecossistema de manguezal na região equatorial, Pará, Brasil}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {241--247} } |
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Silva, J.S.O., Cunha Bustamante, M.M., Markewitz, D., Krusche, A.V. and Ferreira, L.G. | Effects of land cover on chemical characteristics of streams in the Cerrado region of Brazil | 2010 | Biogeochemistry Vol. 105(1-3), pp. 75-88 |
article | DOI URL |
Abstract: The Cerrado is the second largest Brazilian biome and contains the headwaters of three major hydrological basins in Brazil. In spite of the biological and ecological relevance of this biome, there is little information about how land use changes affect the chemistry of low-order streams in the Cerrado. To evaluate these effects streams that drain areas under natural, rural, and urban land cover were sampled near Brasilia, Brazil. Water samples were collected between September 2004 and December 2006. Chemical concentrations generally followed the pattern of Urban textgreater Rural textgreater Natural. Median conductivity of stream water of 21.6 (interquartile: 22.7) mu S/cm in urban streams was three and five-fold greater relative to rural and natural areas, respectively. In the wet season, despite of increasing discharge, concentration of many solutes were higher, particularly in rural and natural streams. Streams also presented higher total dissolved N (TDN) loads from natural to rural and urban although DIN:DON ratios did not differ significantly. In natural and urban streams TDN was 80 and 77% dissolved organic N, respectively. These results indicate that alterations in land cover from natural to rural and urban are changing stream water chemistry in the Cerrado with increasing solute concentrations, in addition to increased TDN output in areas under urban cover, with potential effects on ecosystem function. | |||||
BibTeX:
@article{silva_effects_2010, author = {Silva, José Salomão Oliveira and Cunha Bustamante, Mercedes Maria and Markewitz, Daniel and Krusche, Alex Vladimir and Ferreira, Laerte Guimarães}, title = {Effects of land cover on chemical characteristics of streams in the Cerrado region of Brazil}, journal = {Biogeochemistry}, year = {2010}, volume = {105}, number = {1-3}, pages = {75--88}, url = {://WOS:000294501100006}, doi = {https://doi.org/10.1007/s10533-010-9557-8} } |
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Silva, D.L., Ometto, J., de Araujo Lobo, G., de Paula Lima, W., Scaranello, M., Mazzi, E. and da Rocha, H. | Can land use changes alter carbon, nitrogen and major ion transport in subtropical Brazilian streams? | 2007 | Scientia Agricola Vol. 64(4), pp. 317-324 |
article | URL |
Abstract: Several studies in tropical watersheds have evaluated the impact of urbanization and agricultural practices on water quality. In Brazil, savannas (known regionally as Cerrados) represent 23% of the country's surface, representing an important share to the national primary growth product, especially due to intense agriculture. The purpose of this study is to present a comprehensive evaluation, on a yearly basis, of carbon, nitrogen and major ion fluxes in streams crossing areas under different land use (natural vegetation, sugar cane and eucalyptus) in a savanna region of SE Brazil. Eucalyptus and sugar cane alter the transport of the investigated elements in small watersheds. The highest concentration of all parameters (abiotic parameters, ions, dissolved organic carbon-DOC-and dissolved inorganic carbon-DIC) were found in Sugar Cane Watersheds (SCW). The observed concentrations of major cations in Eucalyptus Watersheds (EW) (Mg, Ca, K, Na), as well as DIN and DOC, were found frequently to be intermediate values between those of Savanna Watersheds (SW) and SCW, suggesting a moderate impact of eucalyptus plantations on the streamwater. Same trends were found in relation to ion and nutrient fluxes, where the higher values corresponded to SCW. It is suggested that sugar cane plantations might be playing an important role in altering the chemistry of water bodies. | |||||
BibTeX:
@article{silva_can_2007, author = {Silva, D.M. L. and Ometto, J.P.H.B. and de Araujo Lobo, G. and de Paula Lima, W. and Scaranello, M.A. and Mazzi, E. and da Rocha, H.R.}, title = {Can land use changes alter carbon, nitrogen and major ion transport in subtropical Brazilian streams?}, journal = {Scientia Agricola}, year = {2007}, volume = {64}, number = {4}, pages = {317--324}, url = {://WOS:000248652800002} } |
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Silva Dias, M.A.F.d. | O Projeto LBA: Experimento de grande escala da interação biosfera atmosfera na amazônia: resultados preliminares [BibTeX] |
2001 | Boletim da Sociedade Brasileira de Meteorologia Vol. 25(1), pp. 7-14 |
article | |
BibTeX:
@article{silva_dias_o_2001, author = {Silva Dias, Maria Assunção Faus da}, title = {O Projeto LBA: Experimento de grande escala da interação biosfera atmosfera na amazônia: resultados preliminares}, journal = {Boletim da Sociedade Brasileira de Meteorologia}, year = {2001}, volume = {25}, number = {1}, pages = {7--14} } |
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Silva Dias, M.A., Avissar, R. and Silva Dias, P. | Modeling the Regional and Remote Climatic Impact of Deforestation [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 251-260 |
incollection | |
BibTeX:
@incollection{m_keller_modeling_2009, author = {Silva Dias, M. A. and Avissar, R. and Silva Dias, P.}, title = {Modeling the Regional and Remote Climatic Impact of Deforestation}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {251--260} } |
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Silva, C., Aragao, L.E.O.C., Barlow, J., Espirito-Santo, F.D., Young, P., Anderson, L.O., Berenguer, E., Brasil, I., Brown, I.F., Castro, B.S., Farias, R., Ferreira, J., Franc¸a, F., Grac¸a, P.M.L.A., Kirsten, L., Lopes, A.P., Salimon, C., Scaranello, M., Seixas, M., Souza, F.C. and Xaud, H.M. | Drought induced Amazonian wildfires instigate a decadalscale disruption of forest carbon dynamics [BibTeX] |
2018 | Phil. Trans. R. Soc. B Vol. 373, pp. 20180043 |
article | DOI |
BibTeX:
@article{silva_drought_2018, author = {Silva, C.V.J. and Aragao, L. E. O. C. and Barlow, J. and Espirito-Santo, F. D. and Young, P.J. and Anderson, L. O. and Berenguer, E. and Brasil, I. and Brown, I. F. and Castro, B. S. and Farias, R. and Ferreira, J. and Franc¸a, F. and Grac¸a, P. M. L. A. and Kirsten, L. and Lopes, A. P. and Salimon, C. and Scaranello, M.A. and Seixas, M. and Souza, F. C. and Xaud, H.A. M.}, title = {Drought induced Amazonian wildfires instigate a decadalscale disruption of forest carbon dynamics}, journal = {Phil. Trans. R. Soc. B}, year = {2018}, volume = {373}, pages = {20180043}, doi = {https://doi.org/10.1098/rstb.2018.0043} } |
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Silva, C.e. and Lyra, R. | Estimativa da altura da Camada Limite Planetária a partir de radiossondagens e por um SODAR: experimento DRY TO WET-AMC/LBA-2002 [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 153-156 |
article | |
BibTeX:
@article{silva_estimativa_2007, author = {Silva, C.M.S. e and Lyra, R.}, title = {Estimativa da altura da Camada Limite Planetária a partir de radiossondagens e por um SODAR: experimento DRY TO WET-AMC/LBA-2002}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {153--156} } |
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Silva, C. and Lyra, R. | Comparação do perfil de vento medido por Radiossondas e por um SODAR durante o experimento DRYTO WET-AMC/LBA [BibTeX] |
2009 | Revista Brasileira de Meteorologia Vol. 24(3), pp. 356-363 |
article | |
BibTeX:
@article{silva_comparacao_2009, author = {Silva, C.M.S. and Lyra, R.F.F.}, title = {Comparação do perfil de vento medido por Radiossondas e por um SODAR durante o experimento DRYTO WET-AMC/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2009}, volume = {24}, number = {3}, pages = {356--363} } |
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Silva, C.M.S. and Freitas, S.R. | Impacto de um mecanismo de disparo da convecção na precipitação simulada com o modelo regional BRAMS sobre a bacia amazônica durante a estação chuvosa de 1999 [BibTeX] |
2015 | Revista Brasileira de Meteorologia Vol. 30, pp. 145-157 |
article | |
BibTeX:
@article{silva_impacto_2015, author = {Silva, C. M. S. and Freitas, S. R.}, title = {Impacto de um mecanismo de disparo da convecção na precipitação simulada com o modelo regional BRAMS sobre a bacia amazônica durante a estação chuvosa de 1999}, journal = {Revista Brasileira de Meteorologia}, year = {2015}, volume = {30}, pages = {145--157} } |
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Silva, C.E.M.d., Gonçalves, J.F.d.C. and Feldpausch, T.R. | Water-use efficiency of tree species following calcium and phosphorus application on an abandoned pasture, central Amazonia, Brazil | 2008 | Environmental and Experimental Botany Vol. 64(2), pp. 189-195 |
article | DOI URL |
Abstract: This research represents one of the first studies in Amazonia to examine soil moisture and water-use efficiency (WUE) in secondary forest (SF) vegetation regrowing on abandoned pastures subjected to reduced nutrient constraints via a nutrient addition experiment. Extensive forested areas (about 80% of deforestation) have been converted to pastures in Amazonia, which were later abandoned following soil degradation and reduction in grass productivity. Colonization of these areas proceeds through species adapted to adverse edaphic conditions, such as low soil nutrients. Yet there is little data from such environments showing the interaction of soil nutrients and water availability on plant physiological processes. The objective of this study was to test whether three common SF tree species have positive physiological responses, e.g. increased photosynthesis and water-use efficiency, when nutrient limitations are relaxed through fertilization. The experiment was conducted on an abandoned pasture in central Amazonia with 6-year-old secondary vegetation following the application of four treatments: control; +phosphorus (P); +phosphorus and lime (P + Ca); and +phosphorus, lime and gypsum (P + Ca + G). The control had higher mean soil moisture at 140 and 180cm depth at the end of the dry season, indicating that the treatment plots responded positively to fertilizer additions by taking up additional water. Trees of Vismia japurensis and Bellucia grossularloides growing on the fertilized plots had the highest net photosynthesis rates (A) (18.7 and 20.4 mu mol m(-2) s(-1), respectively). The three species utilized different strategies with regard to physiological and nutritional response, with V japurensis, regardless of treatment, using these limiting resources most efficiently to colonize abandoned pastures. Trees growing on the P + Ca but not +P alone plots increased A rates, indicating that Ca is an important limiting nutrient in post-pasture secondary succession. The addition of Ca as ash by burning primary and secondary vegetation could explain the rapid growth and dominance of V japurensis in abandoned pasture areas in central Amazonia. The efficiency of Vismia to use limiting resources could lead to a restructuring of SF and altered rates of stand-level productivity. (c) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{silva_water-use_2008, author = {Silva, Carlos Eduardo Moura da and Gonçalves, José Francisco de Carvalho and Feldpausch, Ted R.}, title = {Water-use efficiency of tree species following calcium and phosphorus application on an abandoned pasture, central Amazonia, Brazil}, journal = {Environmental and Experimental Botany}, year = {2008}, volume = {64}, number = {2}, pages = {189--195}, url = {://WOS:000259741700011}, doi = {https://doi.org/10.1016/j.envexpbot.2008.03.001} } |
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Silva, G., J.F.C., F., Luizão, T.R., Morais, F.J., Ribeiro, R.R. and C.E.M., G.O. | Eficiência no uso dos nutrientes por espécies pioneiras crescidas em pastagens degradadas na Amazônia central [BibTeX] |
2006 | Acta Amazonica Vol. 36(4), pp. 503 - 512 |
article | |
BibTeX:
@article{silva_eficiencia_2006-1, author = {Silva, Gonçalves, J.F.C., Feldpausch, T.R., Luizão, F.J., Morais, R.R., Ribeiro, G.O., C.E.M.}, title = {Eficiência no uso dos nutrientes por espécies pioneiras crescidas em pastagens degradadas na Amazônia central}, journal = {Acta Amazonica}, year = {2006}, volume = {36}, number = {4}, pages = {503 -- 512} } |
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Sigler, J.M., Fuentes, J.D., Heitz, R.C., Garstang, M. and Fisch, G. | Ozone dynamics and deposition processes at a deforested site in the Amazon Basin | 2002 | Ambio Vol. 31(1), pp. 21-27 |
article | DOI URL |
Abstract: The goal of this study is to investigate the impact of deforestation on ozone dynamics and deposition in the Brazilian Amazon basin. This goal is accomplished through i) analyses of ozone levels and deposition rates at a deforested site during the rainy season; and ii) comparisons of these data with similar information derived at a forest. At the pasture site maximum ozone mixing ratios reach 20 parts per billion on a volume basis (ppbv) but about 6 ppbv prevail over the forest. Maximum ozone deposition velocities for pastures can reach 0.7 cm s(-1), which is about threefold lower than values derived for forests. Combining ozone abundance and deposition velocities, pasture maximum ozone fluxes reach similar to0.2 mug (ozone) m(-2) s(-1). This flux represents approximately 70% of the deposition rates measured over the forest. Hence, this study suggests that conversion of rainforests to pastures could lead to a net reduction (30%) in the ozone sink in the Amazon. | |||||
BibTeX:
@article{sigler_ozone_2002, author = {Sigler, J. M. and Fuentes, J. D. and Heitz, R. C. and Garstang, M. and Fisch, G.}, title = {Ozone dynamics and deposition processes at a deforested site in the Amazon Basin}, journal = {Ambio}, year = {2002}, volume = {31}, number = {1}, pages = {21--27}, url = {://WOS:000174329400004}, doi = {https://doi.org/10.1639/0044-7447(2002)031%5B0021:odadpa%5D2.0.co;2} } |
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Sierra, E.M., Reu, B., Peñuela, M.C., Thuille, A., Quesada C. A., C.A. and Jiménez | Low vertical transfer rates of carbon inferred from radiocarbon analysis in an Amazon Podzol [BibTeX] |
2013 | Biogeosciences Vol. 10, pp. 3455-3464 |
article | |
BibTeX:
@article{sierra_low_2013, author = {Sierra, E. M. ; Reu, B. ; Peñuela, M. C. ; Thuille, A. ; Quesada, C. A., C. A. ; Jiménez}, title = {Low vertical transfer rates of carbon inferred from radiocarbon analysis in an Amazon Podzol}, journal = {Biogeosciences}, year = {2013}, volume = {10}, pages = {3455--3464} } |
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Siddique, I., Vieira, I., Schmidt, S., Lamb, D., Carvalho, C., Figueiredo, R., Blomberg, S. and Davidson, E. | Nitrogen and phosphorus additions negatively affect tree species diversity in tropical forest regrowth trajectories | 2010 | Ecology Vol. 91(7), pp. 2121-2131 |
article | URL |
Abstract: Nutrient enrichment is increasingly affecting many tropical ecosystems, but there is no information on how this affects tree biodiversity. To examine dynamics in vegetation structure and tree species biomass and diversity, we annually remeasured tree species before and for six years after repeated additions of nitrogen (N) and phosphorus (P) in permanent plots of abandoned pasture in Amazonia. Nitrogen and, to a lesser extent, phosphorus addition shifted growth among woody species. Nitrogen stimulated growth of two common pioneer tree species and one common tree species adaptable to both high- and low-light environments, while P stimulated growth only of the dominant pioneer tree Rollinia exsucca (Annonaceae). Overall, N or P addition reduced tree assemblage evenness and delayed tree species accrual over time, likely due to competitive monopolization of other resources by the few tree species responding to nutrient enrichment with enhanced establishment and/or growth rates. Absolute tree growth rates were elevated for two years after nutrient addition. However, nutrient-induced shifts in relative tree species growth and reduced assemblage evenness persisted for more than three years after nutrient addition, favoring two nutrient-responsive pioneers and one early-secondary tree species. Surprisingly, N + P effects on tree biomass and species diversity were consistently weaker than N-only and P-only effects, because grass biomass increased dramatically in response to N + P addition. The resulting intensified competition probably prevented an expected positive N + P synergy in the tree assemblage. Thus, N or P enrichment may favor unknown tree functional response types, reduce the diversity of coexisting species, and delay species accrual during structurally and functionally complex tropical rainforest secondary succession. | |||||
BibTeX:
@article{siddique_nitrogen_2010, author = {Siddique, I. and Vieira, I.C.G. and Schmidt, S. and Lamb, D. and Carvalho, C.J.R. and Figueiredo, R.O. and Blomberg, S. and Davidson, E.A.}, title = {Nitrogen and phosphorus additions negatively affect tree species diversity in tropical forest regrowth trajectories}, journal = {Ecology}, year = {2010}, volume = {91}, number = {7}, pages = {2121--2131}, note = {Edition: 2010/08/19}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20715634} } |
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Shrivastava Meinrat o. Artaxo, P.B.H.M.J.B.L.K.B.J.C.J.E.R.C.F.J.F.J.D.F.Z.F.J.D.G.M.G.A.H.A.E.G.G.H.G.D.G.A.J.S.H.K.S.L.Y.L.S.M.S.T.M.V.F.M.A.e.a.M.A. | Urban pollution greatly enhances formation of natural aerosols over the Amazon rainforest [BibTeX] |
2019 | Nature Communications Vol. 10 |
article | |
BibTeX:
@article{shrivastava_urban_2019, author = {Shrivastava, Meinrat o. Artaxo, Paulo Barbosa, Henrique M. J. Berg, Larry K. Brito, Joel Ching, Joseph Easter, Richard C. Fan, Jiwen Fast, Jerome D. Feng, Zhe Fuentes, Jose D. Glasius, Marianne Goldstein, Allen H. Alves, Eliane Gomes Gomes, Helber Gu, Dasa Guenther, Alex Jathar, Shantanu H. Kim, Saewung Liu, Ying Lou, Sijia Martin, Scot T. Mcneill, V. Faye Medeiros, Adan, et al., Manish Andreae}, title = {Urban pollution greatly enhances formation of natural aerosols over the Amazon rainforest}, journal = {Nature Communications}, year = {2019}, volume = {10} } |
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Shrivastava, M., Rasool, Q.Z., Zhao, B., Octaviani, M., Zaveri, R.A., Zelenyuk, A., Gaudet, B., Liu, Y., Shilling, J.E., Schneider, J., Schulz, C., Zöger, M., Martin, S.T., Ye, J., Guenther, A., Souza, R.F., Wendisch, M. and Pöschl, U. | Tight Coupling of Surface and In-Plant Biochemistry and Convection Governs Key Fine Particulate Components over the Amazon Rainforest [BibTeX] |
2022 | ACS Earth and Space Chemistry Vol. 6(2), pp. 380-390 |
article | DOI URL |
BibTeX:
@article{shrivastava_tight_2022, author = {Shrivastava, Manish and Rasool, Quazi Z. and Zhao, Bin and Octaviani, Mega and Zaveri, Rahul A. and Zelenyuk, Alla and Gaudet, Brian and Liu, Ying and Shilling, John E. and Schneider, Johannes and Schulz, Christiane and Zöger, Martin and Martin, Scot T. and Ye, Jianhuai and Guenther, Alex and Souza, Rodrigo F. and Wendisch, Manfred and Pöschl, Ulrich}, title = {Tight Coupling of Surface and In-Plant Biochemistry and Convection Governs Key Fine Particulate Components over the Amazon Rainforest}, journal = {ACS Earth and Space Chemistry}, year = {2022}, volume = {6}, number = {2}, pages = {380--390}, url = {https://doi.org/10.1021/acsearthspacechem.1c00356}, doi = {https://doi.org/10.1021/acsearthspacechem.1c00356} } |
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Shimizu, M.H., Ambrizzi, T. and Liebmann, B. | Extreme precipitation events and their relationship with ENSO and MJO phases over northern South America [BibTeX] |
2016 | Int. J. Climatol. | article | DOI |
BibTeX:
@article{shimizu_extreme_2016, author = {Shimizu, M. H. and Ambrizzi, T. and Liebmann, B.}, title = {Extreme precipitation events and their relationship with ENSO and MJO phases over northern South America}, journal = {Int. J. Climatol.}, year = {2016}, doi = {https://doi.org/10.1002/joc.4893} } |
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Shimabukuro, Y.E., Novo, E.M. and Mertes, L.K. | Amazon river mainstem flooodplain landsat TM digital mosaic | 2002 | International Journal of Remote Sensing Vol. 23(1), pp. 57-69 |
article | DOI URL |
Abstract: This paper presents the methodology used to build a Landsat Thematic Mapper (TM) digital mosaic for the Amazon River mainstem floodplain. Twenty-nine almost cloud-free TM Landsat scenes covering a period from 1985 to 1995 were selected from the National Institute for Space Research (INPE) archive. Most of the scenes were acquired from July to September, a period that begins with high waters and ends with receding water up to about the beginning of the low waters. Radiometric rectification was applied to the images to reduce variability of environmental conditions during Landsat TM data acquisition. The radiometric rectification applied had a good performance for bands 3, 5, and 7, for most of the scenes. For bands 1 and 2 the radiometric rectification was limited, especially for scenes with intense haze. Nevertheless, the overall performance of radiometric normalization allowed the production of a uniform dataset for the entire Brazilian Amazon River mainstem floodplain. | |||||
BibTeX:
@article{shimabukuro_amazon_2002, author = {Shimabukuro, Y. E. and Novo, E. M. and Mertes, L. K.}, title = {Amazon river mainstem flooodplain landsat TM digital mosaic}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {1}, pages = {57--69}, url = {://WOS:000172424700005}, doi = {https://doi.org/10.1080/01431160010029165} } |
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Shimabukuro, Y.E., Duarte, V., Arai, E., Freitas, R.M., Lima, A., Valeriano, D.M., Brown, I.F. and Maldonado, M.L.R. | Fraction images derived from Terra Modis data for mapping burnt areas in Brazilian Amazonia | 2009 | International Journal of Remote Sensing Vol. 30(6), pp. 1537-1546 |
article | DOI URL |
Abstract: The objective of this paper is to present a method for mapping burnt areas in Brazilian Amazonia using Terra MODIS data. The proposed approach is based on image segmentation of the shade fraction images derived from MODIS, using a non-supervised classification algorithm followed by an image editing procedure for minimizing misclassifications. Acre State, the focus of this study, is located in the western region of Brazilian Amazonia and undergoing tropical deforestation. The extended dry season in 2005 affected this region creating conditions for extensive forest fires in addition to fires associated with deforestation and land management. The high temporal resolution of MODIS provides information for studying the resulting burnt areas. Landsat 5 TM images and field observations were also used as ground data for supporting and validating the MODIS results. Multitemporal analysis with MODIS showed that about 6500km2 of land surface were burnt in Acre State. Of this, 3700km2 corresponded to the previously deforested areas and 2800km2 corresponded to areas of standing forests. This type of information and its timely availability are critical for regional and global environmental studies. The results showed that daily MODIS sensor data are useful sources of information for mapping burnt areas, and the proposed method can be used in an operational project in Brazilian Amazonia. | |||||
BibTeX:
@article{shimabukuro_fraction_2009, author = {Shimabukuro, Y. E. and Duarte, V. and Arai, E. and Freitas, R. M. and Lima, A. and Valeriano, D. M. and Brown, I. F. and Maldonado, M. L. R.}, title = {Fraction images derived from Terra Modis data for mapping burnt areas in Brazilian Amazonia}, journal = {International Journal of Remote Sensing}, year = {2009}, volume = {30}, number = {6}, pages = {1537--1546}, url = {://WOS:000265415600010}, doi = {https://doi.org/10.1080/01431160802509058} } |
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Shilling Pekour, M.S.F.E.C.A.P.d.S.S.H.J.M.L.K.M.M.L.A.T.M.S.T.S.S.R.T.J.and.W.J.J.E. | Aircraft observations of the chemical composition and aging of aerosol in the Manaus urban plume during GoAmazon 2014/5 [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 10773-10797 |
article | DOI |
BibTeX:
@article{shilling_aircraft_2018, author = {Shilling, Pekour, M. S., Fortner, E. C., Artaxo, P., de Sá, S., Hubbe, J. M., Longo, K. M., Machado, L. A. T., Martin, S. T., Springston, S. R., Tomlinson, J., and Wang, J., J. E.}, title = {Aircraft observations of the chemical composition and aging of aerosol in the Manaus urban plume during GoAmazon 2014/5}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {10773--10797}, doi = {https://doi.org/10.5194/acp-18-10773-2018} } |
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Serra-Neto, E.M., Martins, H.S., Dias-Júnior, C.Q., Santana, R.A., Brondani, D.V., Manzi, A.O., de Araújo, A.C., Teixeira, P.R., Sörgel, M. and Mortarini, L. | Simulation of the Scalar Transport above and within the Amazon Forest Canopy [BibTeX] |
2021 | Atmosphere Vol. 12(12), pp. 1631 |
article | URL |
BibTeX:
@article{serra-neto_simulation_2021, author = {Serra-Neto, Edivaldo M. and Martins, Hardiney S. and Dias-Júnior, Cléo Q. and Santana, Raoni A. and Brondani, Daiane V. and Manzi, Antônio O. and de Araújo, Alessandro C. and Teixeira, Paulo R. and Sörgel, Matthias and Mortarini, Luca}, title = {Simulation of the Scalar Transport above and within the Amazon Forest Canopy}, journal = {Atmosphere}, year = {2021}, volume = {12}, number = {12}, pages = {1631}, url = {https://www.mdpi.com/2073-4433/12/12/1631} } |
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Serique, K.J.d.A., Santos, J.L.C.d. and Albuquerque, A.C.F. | Mo Porã: Uma ferramenta para o gerenciamento distribuído de repositórios de dados científicos na web [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 149-162 |
incollection | |
BibTeX:
@incollection{emilio_mo_2014, author = {Serique, Kleberson Junio do Amaral and Santos, José Laurindo Campos dos and Albuquerque, Andréa Côrrea Flôres}, title = {Mo Porã: Uma ferramenta para o gerenciamento distribuído de repositórios de dados científicos na web}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {149--162}, note = {Section: 13} } |
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Senna, M.A., Costa, M.H. and Shimabukuro, Y. | Fraction of photosynthetically active radiation absorbed by Amazon tropical forest: A comparison of field measurements, modeling, and remote sensing | 2005 | Journal of Geophysical Research-Biogeosciences Vol. 110(G1) |
article | DOI URL |
Abstract: The fraction of absorbed photosynthetically active radiation (FAPAR) is a vegetation biophysical variable that characterizes energy, mass, and momentum exchanges and is used extensively in models that represent the transfer of energy, carbon, water, and the biogeochemistry of terrestrial ecosystems. This paper compares three estimates of FAPAR by an Amazonian tropical rain forest. In the Tapajos National Forest, near Santarem, state of Para, Brazil, FAPAR is estimated based on field measurements, modeling (using IBIS which simulates the fluxes in the soil-vegetation-atmosphere system considering two vegetation layers) and remotely sensed Moderate Resolution Imaging Spectroradiometer (MODIS) monthly FAPAR product, which has not been validated for a tropical rain forest yet. FAPAR based on field observations is calculated from incoming and reflected PAR measurements taken above the canopy, and downward PAR at a 15 m height, corrected to be representative of the entire canopy, obtaining an annual mean value of 0.91. FAPAR simulated by the Integrated Biosphere Simulator (IBIS) is 0.76, while the annual average FAPAR estimated by MODIS is 0.85. If we consider that MODIS estimates include only PAR absorbed by leaves, the remote sensing estimates are very close to field measurements corrected to include only the absorption by leaves (0.87); hence we conclude that the MODIS FAPAR product for the tropical rain forest is reliable to be used in future studies. However, model estimates of FAPAR for the tropical forest are low, and adjustments on the algorithm used to calculate the absorbed radiation by the canopy are necessary. | |||||
BibTeX:
@article{senna_fraction_2005, author = {Senna, M.C. A. and Costa, M. H. and Shimabukuro, Y.E.}, title = {Fraction of photosynthetically active radiation absorbed by Amazon tropical forest: A comparison of field measurements, modeling, and remote sensing}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2005}, volume = {110}, number = {G1}, url = {://WOS:000240983600002}, doi = {https://doi.org/10.1029/2004jg000005} } |
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Sena, E.T., Artaxo, P. and Correia, A. | The impact of deforestation in the Amazonian atmospheric radiative balance: a remote sensing assessment [BibTeX] |
2013 | Atmospheric Chemistry and Physics Vol. 13, pp. 1261-1275 |
article | |
BibTeX:
@article{sena_impact_2013, author = {Sena, E. T. and Artaxo, P. and Correia, A.L.}, title = {The impact of deforestation in the Amazonian atmospheric radiative balance: a remote sensing assessment}, journal = {Atmospheric Chemistry and Physics}, year = {2013}, volume = {13}, pages = {1261--1275} } |
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Sena, E.T., Artaxo, P. and Correia, A.L. | Spatial variability of the direct radiative forcing of biomass burning aerosols and the effects of land use change in Amazonia [BibTeX] |
2013 | Atmos. Chem. Phys. Vol. 13, pp. 1261-1275 |
article | DOI |
BibTeX:
@article{sena_spatial_2013, author = {Sena, E. T. and Artaxo, P. and Correia, A. L.}, title = {Spatial variability of the direct radiative forcing of biomass burning aerosols and the effects of land use change in Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2013}, volume = {13}, pages = {1261--1275}, doi = {https://doi.org/10.5194/acp-13-1261-2013} } |
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Sena, E.T. and Artaxo, P. | A novel methodology using MODIS and CERES for assessing the daily radiative forcing of smoke aerosols in large scale over the Amazonia [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 5471-5483 |
article | DOI |
BibTeX:
@article{sena_novel_2015, author = {Sena, E. T. and Artaxo, P.}, title = {A novel methodology using MODIS and CERES for assessing the daily radiative forcing of smoke aerosols in large scale over the Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {5471--5483}, doi = {https://doi.org/10.5194/acp-15-5471-2015} } |
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Selva, E., Couto, E.G., Johnson, M. and Lehmann, J. | Litterfall production and fluvial export in headwater catchments of the southern Amazon | 2007 | Journal of Tropical Ecology Vol. 23, pp. 329-335 |
article | DOI URL |
Abstract: Resolving the carbon (C) balance in the Amazonian forest depends on an improved quantification of production and losses of particulate C from forested landscapes via stream export. The main goal of this work was to quantify litterfall, the lateral movement of litter, and the export of coarse organic particulate matter (textgreater2 mm) in four small watersheds (1-2 ha) under native forest in southern Amazonia near Juruena, Mato Grosso, Brazil (10 degrees 25 ' S, 58 degrees 46 ' W. Mean litterfall production was 11.8 Mg ha(-1) y(-1) (5.7 Mg C ha(-1) y(-1)). Litterfall showed strong seasonality. with the highest deposition in the driest months of the year. About two times more C per month was deposited on the forest floor during the 6-mo dry season (0.65 Mg C ha(-1) me(-1)) compared with the rainy season (0.3 Mg C ha(-1) mo(-1)). The measured C concentration of the litterfall samples was signiticantly greater in the dry season than in the rainy season (49% vs. 46%). The lateral movement of litter increased from the plateau (upper landscape position) towards the riparian zone. However, the trend in C concentration of laterally transported litter samples was the opposite, being highest on the plateau (44%) and lowest in the riparian zone (42%). Stream-water exports of particulate C were positively correlated with streamflow, increasing in the rainiest months. The export of particulate C in streamflow was found to be very small (less than 1%) in relation to the amount of litterfall produced. | |||||
BibTeX:
@article{selva_litterfall_2007, author = {Selva, E.C. and Couto, E. G. and Johnson, M.S. and Lehmann, J.}, title = {Litterfall production and fluvial export in headwater catchments of the southern Amazon}, journal = {Journal of Tropical Ecology}, year = {2007}, volume = {23}, pages = {329--335}, url = {://WOS:000246935400008}, doi = {https://doi.org/10.1017/s0266467406003956} } |
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Seifert, P., Kunz, C., Baars, H., Ansmann, A., Bühl, J., Senf, F., Engelmann, R., Althausen, D. and Artaxo, P. | Seasonal variability of heterogeneous ice formation in stratiform clouds over the Amazon Basin [BibTeX] |
2015 | Geophysical Research Letters Vol. 42, pp. 5587-5593 |
article | DOI |
BibTeX:
@article{seifert_seasonal_2015, author = {Seifert, P. and Kunz, C. and Baars, H. and Ansmann, A. and Bühl, J. and Senf, F. and Engelmann, R. and Althausen, D. and Artaxo, P.}, title = {Seasonal variability of heterogeneous ice formation in stratiform clouds over the Amazon Basin}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, pages = {5587--5593}, doi = {https://doi.org/10.1002/2015GL064068} } |
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Seidel, M., Yager, P.L., Ward, N.D., Carpenter, E.J., Gomes, H.R., Krusche, A.V., Richey, J.E., Dittmar, T. and Medeiros, P.M. | Molecular-level changes of dissolved organic matter along the Amazon River-to-ocean continuum [BibTeX] |
2015 | Marine Chemistry Vol. 177(2), pp. 218-231 |
article | |
BibTeX:
@article{seidel_molecular-level_2015, author = {Seidel, M. and Yager, Patricia L. and Ward, Nicholas D. and Carpenter, Edward J. and Gomes, Helga R. and Krusche, Alex V. and Richey, Jeffrey E. and Dittmar, Thorsten; and Medeiros, Patricia M.}, title = {Molecular-level changes of dissolved organic matter along the Amazon River-to-ocean continuum}, journal = {Marine Chemistry}, year = {2015}, volume = {177}, number = {2}, pages = {218--231} } |
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Scott, S.A., Spracklen, D.V., Arnold, S.R., Forster, P.M., Rap, A., Äijälä, M., Artaxo, P., Carslaw, K.S., Chipperfield, M.P., Ehn, M., Gilardoni, S., Heikkinen, L., Kulmala, M., Petäjä, T., Reddington, C.L.S., Rizzo, L.V., Swietlicki, E., Vignati, E., Wilson C., C.E. and Monks | Impact on short-lived climate forcers increases projected warming due to deforestation [BibTeX] |
2018 | Nature Communications Vol. 9, pp. 157-166 |
article | |
BibTeX:
@article{scott_impact_2018, author = {Scott, S. A. ; Spracklen, D. V. ; Arnold, S. R. ; Forster, P. M. ; Rap, A. ; Äijälä, M. ; Artaxo, P. ; Carslaw, K. S. ; Chipperfield, M. P. ; Ehn, M. ; Gilardoni, S. ; Heikkinen, L. ; Kulmala, M. ; Petäjä, T. ; Reddington, C. L. S. ; Rizzo, L. V. ; Swietlicki, E. ; Vignati, E. ; Wilson, C., C. E. ; Monks}, title = {Impact on short-lived climate forcers increases projected warming due to deforestation}, journal = {Nature Communications}, year = {2018}, volume = {9}, pages = {157--166} } |
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Scott, S., D. V., P., J. R., R., D’Andrea, I., S. D., R., Carslaw, A., K. S., F., P. M., A., Kulmala, P., Rizzo, M., L. V., S., Mann, E., G. W., P. and K. J., C.E. | Impact of gas-to-particle partitioning approaches on the simulated radiative effects of biogenic secondary organic aerosol [BibTeX] |
2015 | Atmospheric Chemistry and Physics Vol. 15, pp. 12989-13001 |
article | DOI |
BibTeX:
@article{scott_impact_2015, author = {Scott, Spracklen, D. V., Pierce, J. R., Riipinen, I., D’Andrea, S. D., Rap, A., Carslaw, K. S., Forster, P. M., Artaxo, P., Kulmala, M., Rizzo, L. V., Swietlicki, E., Mann, G. W., Pringle, K. J., C. E.}, title = {Impact of gas-to-particle partitioning approaches on the simulated radiative effects of biogenic secondary organic aerosol}, journal = {Atmospheric Chemistry and Physics}, year = {2015}, volume = {15}, pages = {12989--13001}, note = {Edition: www.atmos-chem-phys.net/15/12989/2015/ .}, doi = {https://doi.org/10.5194/acp-15-12989-2015} } |
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Scott C. Stark Scott R. Saleska, V.L.J.S.M.L.L.F.A.P.B.C.and.R.C.O.B.J.E. | Linking canopy leaf area and light environments with tree size distributions to explain Amazon forest demography [BibTeX] |
2015 | Ecology Letters Vol. 18(7), pp. 636-645 |
article | DOI |
BibTeX:
@article{scott_c_stark_linking_2015, author = {Scott C. Stark, Scott R. Saleska, Veronika Leitold, Juliana Schietti, Marcos Longo, Luciana F. Alves, Plinio B. Camargo and Raimundo C. Oliveira, Brian J. Enquist}, title = {Linking canopy leaf area and light environments with tree size distributions to explain Amazon forest demography}, journal = {Ecology Letters}, year = {2015}, volume = {18}, number = {7}, pages = {636--645}, doi = {https://doi.org/10.1111/ele.12440} } |
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Scofield, V., Melack, J., Barbosa, P., Amaral, J., Forsberg, B. and Farjalla, V. | Carbon dioxide outgassing from Amazonian aquatic ecosystems in the Negro River basin [BibTeX] |
2016 | Biogeochemistry | article | DOI |
BibTeX:
@article{scofield_carbon_2016, author = {Scofield, V. and Melack, J.M. and Barbosa, P.M. and Amaral, J.H.F. and Forsberg, B.R. and Farjalla, V.}, title = {Carbon dioxide outgassing from Amazonian aquatic ecosystems in the Negro River basin}, journal = {Biogeochemistry}, year = {2016}, doi = {https://doi.org/10.1007/s10533-016-0220-x} } |
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Schwerdtfeger, J., Weiler, M., Johnson, M. and Couto, E. | Estimating water balance components of tropical wetland lakes in the Pantanal dry season, Brazil [BibTeX] |
2014 | Journal des Sciences Hydrologiques Vol. 59(12) |
article | DOI |
BibTeX:
@article{schwerdtfeger_estimating_2014, author = {Schwerdtfeger, J. and Weiler, M. and Johnson, M.S. and Couto, E.G.}, title = {Estimating water balance components of tropical wetland lakes in the Pantanal dry season, Brazil}, journal = {Journal des Sciences Hydrologiques}, year = {2014}, volume = {59}, number = {12}, doi = {https://doi.org/10.1080/02626667.2013.870665} } |
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Schwendenmann, L. and Veldkamp, E. | Long-term CO2 production from deeply weathered soils of a tropical rain forest: evidence for a potential positive feedback to climate warming | 2006 | Global Change Biology Vol. 12(10), pp. 1878-1893 |
article | DOI URL |
Abstract: Currently, it is unknown what role tropical forest soils will play in the future global carbon cycle under higher temperatures. Many tropical forests grow on deeply weathered soils and although it is generally accepted that soil carbon decomposition increases with higher temperatures, it is not known whether subsurface carbon pools are particularly responsive to increasing soil temperatures. Carbon dioxide (CO2) diffusing out of soils is an important flux in the global carbon. Although soil CO2 efflux has been the subject of many studies in recent years, it remains difficult to deduct controls of this flux because of the different sources that produce CO2 and because potential environmental controls like soil temperature and soil moisture often covary. Here, we report results of a 5-year study in which we measured soil CO2 production on two deeply weathered soil types at different depths in an old-growth tropical wet forest in Costa Rica. Three sites were developed on old river terraces (old alluvium) and the other three were developed on old lava flows (residual). Annual soil CO2 efflux varied between 2.8-3.6 mu mol CO2-C m(-2) s(-1) (old alluvium) and 3.4-3.9 mu mol CO2-C m(-2) s(-1) (residual). More than 75% of the CO2 was produced in the upper 0.5 m (including litter layer) and less than 7% originated from the soil below 1 m depth. This low contribution was explained by the lack of water stress in this tropical wet forest which has resulted in very low root biomass below 2 m depth. In the top 0.5 m CO2 production was positively correlated with both temperature and soil moisture; between 0.6 and 2 m depth CO2 production correlated negatively with soil moisture in one soil and positively with photosynthetically active radiation in the other soil type. Below 2 m soil CO2 production strongly increased with increasing temperature. In combination with reduced tree growth that has been shown for this ecosystem, this would be a strong positive feedback to ecosystem warming. | |||||
BibTeX:
@article{schwendenmann_long-term_2006, author = {Schwendenmann, Luitgard and Veldkamp, Edzo}, title = {Long-term CO2 production from deeply weathered soils of a tropical rain forest: evidence for a potential positive feedback to climate warming}, journal = {Global Change Biology}, year = {2006}, volume = {12}, number = {10}, pages = {1878--1893}, url = {://WOS:000240561000006}, doi = {https://doi.org/10.1111/j.1365-2486.2006.01235.x} } |
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Schwendener, C.M., Lehmann, J., de Camargo, P.B., Luizao, R.C.C. and Fernandes, E.C.M. | Nitrogen transfer between high- and low-quality leaves on a nutrient-poor Oxisol determined by N-15 enrichment | 2005 | Soil Biology & Biochemistry Vol. 37(4), pp. 787-794 |
article | DOI URL |
Abstract: It has been proposed that the C/N ratio, or quality, of litter or mulch mixtures affects N release. Although total N release from these mixtures and the effects on soil N are relatively well understood, a mechanistic understanding of the interactions between litter species with respect to their N release is still lacking. This study examines decomposition and N dynamics in mixtures of high-quality leguminous mulch, gliricidia [Gliricidia sepium (Jacq.) Kunth. ex Walp.] with a C/N ratio of 13, and low-quality cupuacu [Theobroma grandiflorum (Wild. ex Spring) Schumann] litter with a C/N ratio of 42, which occur in combination in agroforestry systems. Ratios of 100:0, 80:20, 50:50, 20:80, 0: 100 of fresh N-15-enriched gliricidia leaves and senescent cupuacu leaves, totaling the same dry weight of 6.64 t ha(-1), were applied to an Oxisol and sampled at 6, 14, 38, and 96 days after application. After more than 40% of the N in the gliricidia leaves had been released and the microbial biomass N reached its peak, a significant increase in available soil N occurred at day 14, which was more pronounced with greater amounts of gliricidia in the leaf mixture. However, relative to the N applied in the leaf mixture, there was no significant difference in available soil N with greater proportions of gliricidia. Total N release from the mixtures corresponded to the total N applied by gliricidia. Until day 38, cupuacu C mineralization was significantly faster in the presence of the highest proportion of gliricidia compared to lower proportions. This faster C mineralization of more than 0.5% per day, however, did not increase total C loss or N release from cupuacu leaves after 96 days. The use of N-15 tracers identified an N transfer from gliricidia leaves and the soil to cupuacu leaves and consequently, a lower N release from gliricidia to the soil in the presence of cupuacu leaves. Though we expected that available N in the soil would also decrease with greater amounts of cupuacu litter in the mixture, our results indicated an additive effect of the two species on N release and soil mineral N, with gross interactions between them canceling net interactive effects. Therefore, N release of leaf mixtures behaved as predicted from a calculated sum of individual release patterns, in spite of a transfer of N from the high- to the low-quality leaves. (C) 2004 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{schwendener_nitrogen_2005, author = {Schwendener, C. M. and Lehmann, J. and de Camargo, P. B. and Luizao, R. C. C. and Fernandes, E. C. M.}, title = {Nitrogen transfer between high- and low-quality leaves on a nutrient-poor Oxisol determined by N-15 enrichment}, journal = {Soil Biology & Biochemistry}, year = {2005}, volume = {37}, number = {4}, pages = {787--794}, url = {://WOS:000226872900018}, doi = {https://doi.org/10.1016/j.soilbio.2004.10.011} } |
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Schwendener Lehmann, J.R.M.W.E.F.E.C. | Soil mineral N dynamics beneath mixtures of leaves from legume and fruit trees in Central Amazonian multi-strata agroforests [BibTeX] |
2007 | Acta Amazonica Vol. 37, pp. 313-320 |
article | |
BibTeX:
@article{schwendener_soil_2007, author = {Schwendener, Lehmann, J., Rondon, M., Wandelli, E.V., Fernandes E.C.M., C.M.}, title = {Soil mineral N dynamics beneath mixtures of leaves from legume and fruit trees in Central Amazonian multi-strata agroforests}, journal = {Acta Amazonica}, year = {2007}, volume = {37}, pages = {313--320} } |
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Schwartzman, S., Moreira, A. and Nepstad, D. | Rethinking tropical forest conservation: Perils in parks | 2000 | Conservation Biology Vol. 14(5), pp. 1351-1357 |
article | DOI URL |
Abstract: According to some conservationists, large, pristine, uninhabited parks are the defining criterion of success in conserving tropical forests. They argue that harman residents in tropical forests inevitably deplete populations of large animals through hunting, which triggers a chain reaction of ecological events that greatly diminish the conservation value of these forests Hence; they believe that removal of people from tropical forests is an essential step in the creation of successful parks and in the conservation of nature in the tropics. This approach can lead to undesirable consequences, however, forest residents-and rural people generally-are potent political actors in tropical forest regions and an essential component of the environmental political constituencies that are necessary for the long-term conservation of tropical forests. In Amazonia and elsewhere, rural people are defending far bigger areas of tropical forest from unfettered deforestation and logging than are parks, thereby conserving the ecological services provided by these forests and the majority of their component plant and animal species. Moreover, the data are too sparse to judge the effects of forest peoples on populations of large forest animals. The establishment of pristine, tropical forest parks is an important conservation goal, but the exclusive pursuit of this goal undermines the broader objectives of conservation when it identifies forest residents and other rural people as the enemies of nature. | |||||
BibTeX:
@article{schwartzman_rethinking_2000, author = {Schwartzman, S. and Moreira, A. and Nepstad, D.}, title = {Rethinking tropical forest conservation: Perils in parks}, journal = {Conservation Biology}, year = {2000}, volume = {14}, number = {5}, pages = {1351--1357}, url = {://WOS:000089816800021}, doi = {https://doi.org/10.1046/j.1523-1739.2000.99329.x} } |
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Schwalm, C.R., Williams, C.A., Schaefer, K., Baker, I., Collatz, G.J. and Rödenbeck, C. | Does terrestrial drought explain global CO2 flux anomalies induced by El Niño? | 2011 | Biogeosciences Vol. 8(9), pp. 2493-2506 |
article | DOI URL |
Abstract: The El Nino Southern Oscillation is the dominant year-to-year mode of global climate variability. El Nino effects on terrestrial carbon cycling are mediated by associated climate anomalies, primarily drought, influencing fire emissions and biotic net ecosystem exchange (NEE). Here we evaluate whether El Nino produces a consistent response from the global carbon cycle. We apply a novel bottom-up approach to estimating global NEE anomalies based on FLUXNET data using land cover maps and weather reanalysis. We analyze 13 years (1997-2009) of globally gridded observational NEE anomalies derived from eddy covariance flux data, remotely-sensed fire emissions at the monthly time step, and NEE estimated from an atmospheric transport inversion. We evaluate the overall consistency of biospheric response to El Nino and, more generally, the link between global CO(2) flux anomalies and El Nino-induced drought. Our findings, which are robust relative to uncertainty in both methods and time-lags in response, indicate that each event has a different spatial signature with only limited spatial coherence in Amazonia, Australia and southern Africa. For most regions, the sign of response changed across El Nino events. Biotic NEE anomalies, across 5 El Nino events, ranged from -1.34 to +0.98 Pg C yr(-1), whereas fire emissions anomalies were generally smaller in magnitude (ranging from -0.49 to +0.53 Pg C yr(-1)). Overall drought does not appear to impose consistent terrestrial CO(2) flux anomalies during El Ninos, finding large variation in globally integrated responses from -1.15 to +0.49 Pg C yr(-1). Despite the significant correlation between the CO(2) flux and El Nino indices, we find that El Nino events have, when globally integrated, both enhanced and weakened terrestrial sink strength, with no consistent response across events. | |||||
BibTeX:
@article{schwalm_does_2011, author = {Schwalm, C. R. and Williams, C. A. and Schaefer, K. and Baker, I. and Collatz, G. J. and Rödenbeck, C.}, title = {Does terrestrial drought explain global CO2 flux anomalies induced by El Niño?}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {9}, pages = {2493--2506}, url = {://WOS:000295375700006}, doi = {https://doi.org/10.5194/bg-8-2493-2011} } |
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Schumacher, C., Zhang, M.H. and Ciesielski, P.E. | Heating structures of the TRMM field campaigns | 2007 | Journal of the Atmospheric Sciences Vol. 64(7), pp. 2593-2610 |
article | DOI URL |
Abstract: Heating profiles calculated from sounding networks and other observations during three Tropical Rainfall Measuring Mission (TRMM) field campaigns [the Kwajalein Experiment (KWAJEX), TRMM Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), and South China Sea Monsoon Experiment (SCSMEX)] show distinct geographical differences between oceanic, continental, and monsoon regimes. Differing cloud types (both precipitating and nonprecipitating) play an important role in determining the total diabatic heating profile. Variations in the vertical structure of the apparent heat source, Q(1) can be related to the diurnal cycle, large-scale forcings such as atmospheric waves, and rain thresholds at each location. For example, TRMM-LBA, which occurred in the Brazilian Amazon, had mostly deep convection during the day while KWAJEX, which occurred in the western portion of the Pacific intertropical convergence zone, had more shallow and moderately deep daytime convection. Therefore, the afternoon height of maximum heating was more bottom heavy (i.e., heating below 600 hPa) during KWAJEX compared to TRMM-LBA. More organized convective systems with extensive stratiform rain areas and upper-level cloud decks tended to occur in the early and late morning hours during TRMM-LBA and KWAJEX, respectively, thereby causing Q(1) profiles to be top heavy (i.e., maxima from 600 to 400 hPa) at those times. SCSMEX, which occurred in the South China Sea during the monsoon season, had top-heavy daytime and nighttime heating profiles suggesting that mesoscale convective systems occurred throughout the diurnal cycle, although more precipitation and upper-level cloud in the afternoon caused the daytime heating maximum to be larger. A tendency toward bottom- and top-heavy heating profile variations is also associated with the different cloud types that occurred before and after the passage of easterly wave troughs during KWAJEX, the easterly and westerly regimes during TRMM-LBA, and the monsoon onset and postonset active periods during SCSMEX. Rain thresholds based on heavy, moderate, and light/no-rain amounts can further differentiate top-heavy heating, bottom-heavy heating, and tropospheric cooling. These budget studies suggest that model calculations and satellite retrievals of Q(1) must account for a large number of factors in order to accurately determine the vertical structure of diabatic heating associated with tropical cloud systems. | |||||
BibTeX:
@article{schumacher_heating_2007, author = {Schumacher, Courtney and Zhang, Minghua H. and Ciesielski, Paul E.}, title = {Heating structures of the TRMM field campaigns}, journal = {Journal of the Atmospheric Sciences}, year = {2007}, volume = {64}, number = {7}, pages = {2593--2610}, url = {://WOS:000248335400023}, doi = {https://doi.org/10.1175/jas3938.1} } |
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Schulze, E.D. | Biological control of the terrestrial carbon sink | 2006 | Biogeosciences Vol. 3(2), pp. 147-166 |
article | URL |
Abstract: This lecture reviews the past (since 1964 when the International Biological Program began) and the future of our understanding of terrestrial carbon fluxes with focus on photosynthesis, respiration, primary-, ecosystem-, and biomeproductivity. Photosynthetic capacity is related to the nitrogen concentration of leaves, but the capacity is only rarely reached under field conditions. Average rates of photosynthesis and stomatal conductance are closely correlated and operate near 50% of their maximal rate, with light being the limiting factor in humid regions and air humidity and soil water the limiting factor in arid climates. Leaf area is the main factor to extrapolate from leaves to canopies, with maximum surface conductance being dependent on leaf level stomatal conductance. Additionally, gas exchange depends also on rooting depth which determines the water and nutrient availability and on mycorrhizae which regulate the nutrient status. An important anthropogenic disturbance is the nitrogen uptake from air pollutants, which is not balanced by cation uptake from roots and this may lead to damage and breakdown of the plant cover. Photosynthesis is the main carbon input into ecosystems, but it alone does not represent the ecosystem carbon balance, which is determined by respiration of various kinds. Plant respiration and photosynthesis determine growth (net primary production) and microbial respiration balances the net ecosystem flux. In a spruce forest, 30% of the assimilatory carbon gain is used for respiration of needles, 20% is used for respiration in stems. Soil respiration is about 50% the carbon gain, half of which is root respiration, half is microbial respiration. In addition, disturbances lead to carbon losses, where fire, harvest and grazing bypass the chain of respiration. In total, the carbon balance at the biome level is only about 1% of the photosynthetic carbon input, or may indeed become negative. The recent observed increase in plant growth has different reasons depending on the region of the world: anthropogenic nitrogen deposition is the controlling factor in Europe, increasing global temperatures is the main factor in Siberia, and maybe rising CO(2) the factor controlling the carbon fluxes in Amazonia. However, this has not lead to increases in net biome productivity, due to associated losses. Also important is the interaction between biodiversity and biogeochemical processes. It is shown that net primary productivity increases with plant species diversity (50% species loss equals 20% loss in productivity). However, in this extrapolation the action of soil biota is poorly understood although soils contribute the largest number of species and of taxonomic groups to an ecosystem. The global terrestrial carbon budget strongly depends on areas with pristine old growth forests which are carbon sinks. The management options are very limited, mostly short term, and usually associated with high uncertainty. Unmanaged grasslands appear to be a carbon sink of similar magnitude as forest, but generally these ecosystems lost their C with grazing and agricultural use. Extrapolation to the future of Earth climate shows that the biota will not be able to balance fossil fuel emissions, and that it will be essential to develop a carbon free energy system in order to maintain the living conditions on earth. | |||||
BibTeX:
@article{schulze_biological_2006, author = {Schulze, E. D.}, title = {Biological control of the terrestrial carbon sink}, journal = {Biogeosciences}, year = {2006}, volume = {3}, number = {2}, pages = {147--166}, url = {://WOS:000239461000003} } |
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Schulz Schneider, J.A.H.B.A.O.C.A.d.S.S.S.D.V.F.D.J.-W.T.K.T.K.C.K.M.M.S.T.M.S.P.M.L.S.D.V.C.W.A.W.B.Z.H.Z.M.A.M.O.A.P.M.L.A.T.P.U.W.M.and.B.S.C. | Aircraft-based observations of isoprene-epoxydiol-derived secondary organic aerosol (IEPOX-SOA) in the tropical upper troposphere over the Amazon region [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 14979-15001 |
article | DOI |
BibTeX:
@article{schulz_aircraft-based_2018, author = {Schulz, Schneider, J., Amorim Holanda, B., Appel, O., Costa, A., de Sá, S. S., Dreiling, V., Fütterer, D., Jurkat-Witschas, T., Klimach, T., Knote, C., Krämer, M., Martin, S. T., Mertes, S., Pöhlker, M. L., Sauer, D., Voigt, C., Walser, A., Weinzierl, B., Ziereis, H., Zöger, M., Andreae, M. O., Artaxo, P., Machado, L. A. T., Pöschl, U., Wendisch, M., and Borrmann, S., C.}, title = {Aircraft-based observations of isoprene-epoxydiol-derived secondary organic aerosol (IEPOX-SOA) in the tropical upper troposphere over the Amazon region}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {14979--15001}, doi = {https://doi.org/10.5194/acp-18-14979-2018} } |
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Schroth, G., Moraes, V. and da Mota, M.S.S. | Increasing the profitability of traditional, planted rubber agroforests at the Tapajos river, Brazilian Amazon | 2004 | Agriculture Ecosystems & Environment Vol. 102(3), pp. 319-339 |
article | DOI URL |
Abstract: The planted rubber agroforests of the Tapajos region in eastern Para State, Brazilian Amazon, are a traditional land use practice of intermediate intensity between extractivism in natural forest and plantation agriculture, and thus of potential interest especially for inhabited conservation areas and Extractive Reserves. We measured rubber production of five groves of 23-40 years of age on representative soil types and landscape positions of the region during one tapping season and tested options for improving rubber production in a series of on-farm experiments. The groves contained 650-700 rubber trees with a dbh textgreater10 cm ha(-1), plus variable numbers of smaller rubber trees. Rubber trees contributed 72-97% to the total basal area of the groves. Average dry rubber production per grove varied between 30 and 75 g per tree per week, with an average of 50 g. Income from rubber tapping at the present level of productivity was unlikely to exceed one Brazilian minimum salary for most farmers. Stimulation of the latex flux with a conventional chemical stimulant, ethephon, increased rubber production per week by up to 38%, but the response was highly variable between groves. The attempt to substitute the chemical stimulant by a locally produced, biological product was unsuccessful. There seemed to be considerable potential for improving tree health while increasing rubber production per unit time through the use of improved tapping practices, especially for old trees. From the two tapping knives and methods that are used in the region, the Amazonian method gave significantly higher yields per tree than the southeast Asian method; this adds to better protection of the trees from panel diseases and therefore greater longevity of the groves. Stem diameter, crown form and crown position of the rubber trees were all significantly related to rubber production, suggesting that too early tapping (which reduces growth) and excessively dense stands should be avoided; however, the predictive power of these variables was poor, and this may explain why farmers are reluctant to thin their stands and believe that mature rubber trees are not negatively affected by a secondary forest environment. Even in groves with low average productivity some very high-yielding trees were found, with the most productive ones attaining 250-300 g of dry rubber per tree per week. This points to a considerable value of these traditional agroforests as genetic reservoirs, and to opportunities to establish more productive groves through a rigorous process of seed and plant selection, without the need to drastically alter the traditional agroforestry practices. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{schroth_increasing_2004, author = {Schroth, G. and Moraes, V. and da Mota, M. S. S.}, title = {Increasing the profitability of traditional, planted rubber agroforests at the Tapajos river, Brazilian Amazon}, journal = {Agriculture Ecosystems & Environment}, year = {2004}, volume = {102}, number = {3}, pages = {319--339}, url = {://WOS:000220873500007}, doi = {https://doi.org/10.1016/j.agee.2003.09.001} } |
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Schroth, G., Lehmann, J., Rodrigues, M.R.L., Barros, E. and Macedo, J.L.V. | Plant-soil interactions in multistrata agroforestry in the humid tropics | 2001 | Agroforestry Systems Vol. 53(2), pp. 85-102 |
article | DOI URL |
Abstract: Multistrata agroforestry systems with tree crops comprise a variety of land use systems ranging from plantations of coffee, cacao or tea with shade trees to highly diversified homegardens and multi-storey tree gardens. Research on plant-soil interactions has concentrated on the former. Tree crop- based land use systems are more efficient in maintaining soil fertility than annual cropping systems. Certain tree crop plantations have remained productive for many decades, whereas homegardens have existed in the same place for centuries. However, cases of fertility decline under tree crops, including multistrata agroforestry systems, have also been reported, and research on the causal factors (both socioeconomic and biophysical) is needed. Plantation establishment is a critical phase, during which the tree crops require inputs but do not provide economic outputs. In larger plantations, tree crops are often established together with a leguminous cover crop, whereas in smallholder agriculture, the initial association with food crops and short-lived cash crops can have both socioeconomic and biological advantages. Fertilizers applied to, and financed by, such crops can help to `recapitalize' soil fertility and improve the development conditions of the young tree crops. Favorable effects on soil fertility and crop nutrition have been observed in associations of tree crops with N-2-fixing legume trees, especially under N-deficient conditions. Depending on site conditions, the substitution of legume `service' trees with fast-growing timber trees may lead to problems of competition for nutrients and water, which may be alleviated through appropriate planting designs. The reduction of nutrient leaching and the recycling of subsoil nutrients are ways to increase the availability of nutrients in multistrata systems, and at the same time, reduce negative environmental impacts. These processes are optimized through fuller occupation of the soil volume by roots, allowing a limited amount of competition between associated species. The analysis of temporal and spatial patterns of water and nutrient availability within a system helps to optimize the use of soil resources, e.g., by showing where more plants can be added or fertilizer rates reduced. Important research topics in multistrata agroforestry include plantation establishment, plant arrangement and management for maximum complementarity of resource use in space and time, and the optimization of soil biological processes, such as soil organic matter build-up and the stabilization and improvement of soil structure by roots, fauna and microflora. | |||||
BibTeX:
@article{schroth_plant-soil_2001, author = {Schroth, G. and Lehmann, J. and Rodrigues, M. R. L. and Barros, E. and Macedo, J. L. V.}, title = {Plant-soil interactions in multistrata agroforestry in the humid tropics}, journal = {Agroforestry Systems}, year = {2001}, volume = {53}, number = {2}, pages = {85--102}, url = {://WOS:000172858700002}, doi = {https://doi.org/10.1023/a:1013360000633} } |
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Schroth, G., Elias, M.E.A., Uguen, K., Seixas, R. and Zech, W. | Nutrient fluxes in rainfall, throughfall and stemflow in tree-based land use systems and spontaneous tree vegetation of central Amazonia | 2001 | Agriculture Ecosystems & Environment Vol. 87(1), pp. 37-49 |
article | DOI URL |
Abstract: The quantification of nutrient fluxes is an important step in the development of sustainable land use systems, especially on low-fertility soils of the humid tropics. Nutrient concentrations in rainfall (RF), throughfall (TF) and stemflow (SF) were measured for ten rainfall events in a polyculture (multi-strata agroforestry system) composed of five tree crops, three tree crop monocultures, spontaneous tree fallow and two rainforest tree species in central Amazonia and nutrient fluxes were calculated for a 1 year period. Nutrient inputs in wet deposition during 1 year were 5.5 kg ha(-1) of total N, of which 42% were in the organic form, 0.07 kg ha(-1) of total P, of which 71% were in the organic form, 2.6 kg ha(-1) of K, 0.8 ka ha(-1) of Ca and 0.3 kg ha(-1) of Mg. The nutrient concentrations in TF and SF were influenced by tree species, land use system, nutrient status of the trees and size of the rain events. The rainforest species had high N but low P concentrations in their TF and SR The highest P concentrations were measured in SF of annatto (Bixa orellana), which was 115 times richer in total P and 400 times richer in phosphate-P than RF for small rain events. Higher fertilizer application increased the concentrations of P and Mg in TF and SF. On the plot level, the nutrient fluxes in TF and SF were greatest in the systems with the highest plant density and crown cover (fallows and palm monocultures). On the species level, strong increases of the nutrient fluxes in TF and SF were observed close to the stem of certain trees compared with the plot average (more than 10 fold for P, K and Mg under peach palm Bactris gasipaes). In the polycultures and the fallow, the recycling of N, P, Ca and Mg in TF and SF was about 5-10% of the total recycling including Litterfall, but was 50-53% for K (77% in the peach palm monocultures). Throughfall and SF are most relevant for K cycling and by influencing small-scale patterns of nutrient inputs into the soil. Stemflow is especially important in vegetation with high stem density, such as certain fallows and in systems dominated by palms. These results can help to devise measurement programs for nutrient cycling in tree-dominated land use systems and spontaneous vegetation in the humid tropics. Possible effects of concentrated nutrient solutions on microbial processes in soil and litter merit further investigation. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{schroth_nutrient_2001, author = {Schroth, G. and Elias, M. E. A. and Uguen, K. and Seixas, R. and Zech, W.}, title = {Nutrient fluxes in rainfall, throughfall and stemflow in tree-based land use systems and spontaneous tree vegetation of central Amazonia}, journal = {Agriculture Ecosystems & Environment}, year = {2001}, volume = {87}, number = {1}, pages = {37--49}, url = {://WOS:000171487500004}, doi = {https://doi.org/10.1016/s0167-8809(00)00294-2} } |
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Schroth, G., D'Angelo, S.A., Teixeira, W.G., Haag, D. and Lieberei, R. | Conversion of secondary forest into agroforestry and monoculture plantations in Amazonia: consequences for biomass, litter and soil carbon stocks after 7 years | 2002 | Forest Ecology and Management Vol. 163(1-3), pp. 131-150 |
article | DOI URL |
Abstract: Large areas of primary forest in Amazonia have been cleared for cropping or pasture, thereby releasing carbon into the atmosphere. Part of this carbon is re-assimilated by secondary forest after the land has been abandoned. Agroforestry and tree crop plantations are options for the economic valorization of previously cleared land in the humid tropics however, for evaluating the consequences of these land uses for regional carbon flows when established on secondary forest land, information is needed on carbon accumulation in the biomass and soil of these land use systems and of the successional vegetation that they replace. Above- and belowground biomass and litter accumulation were measured for three multistrata. agroforestry systems and five tree crop monocultures seven years after their establishment on secondary forest land on a xanthic Ferralsol in central Amazonia. The biomass of the tree crop systems was compared with that of the 14-year-old secondary forest that would have covered the area in their absense. The agroforestry systems were studied at two fertilization levels. Allometric relationships were developed for estimating the aboveground biomass of eight tree crop species, and root systems were excavated to determine root-shoot-ratios. Depending on species composition and fertilizer input, the multistrata systems had an aboveground biomass of 13.2-42.3 t per ha, a belowground biomass of 4.3-12.9 t per ha, and a litter mass of 2.3-7.2 t per ha. The monocultures had an aboveground biomass of 7.7-56.7 t per ha, a root biomass of 3.2-17.1 t per ha and a litter mass of 1.9-5.6 t per ha. The combined biomass and litter was highest in the peach palm for fruit (Bactris gasipaes) monoculture, followed by two of the multistrata systems. The 14-year-old secondary forest had a combined biomass and litter stock of 127 t per ha. The soil carbon stocks tended to be lower in the agricultural systems than under adjacent primary forest in the topsoil, but not when summed over the soil profile to 2 in depth. Multistrata agroforestry had several advantages over monocultures as it allowed to combine high and long-term biomass accumulation with early generation of income from annual and semiperennial intercrops, increased growth and earlier yields of certain tree crops, long-term accumulation of capital in larger trees, and more complete occupation of the soil than in common tree crop monocultures of the region. Trees with low litter quality seemed to have a favourable effect on soil carbon even when associated with species with high litter quality and could be used as an insurance against soil organic matter loss under tree crop agriculture. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{schroth_conversion_2002, author = {Schroth, G. and D'Angelo, S. A. and Teixeira, W. G. and Haag, D. and Lieberei, R.}, title = {Conversion of secondary forest into agroforestry and monoculture plantations in Amazonia: consequences for biomass, litter and soil carbon stocks after 7 years}, journal = {Forest Ecology and Management}, year = {2002}, volume = {163}, number = {1-3}, pages = {131--150}, url = {://WOS:000176460500011}, doi = {https://doi.org/10.1016/s0378-1127(01)00537-0} } |
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Schroth, G., Coutinho, P., Moraes, V.H.F. and Albernaz, A.L. | Rubber agroforests at the Tapajo's river, Brazilian Amazon - environmentally benign land use systems in an old forest frontier region | 2003 | Agriculture Ecosystems & Environment Vol. 97(1-3), pp. 151-165 |
article | DOI URL |
Abstract: Scientific and public attention concerned with natural rubber (Hevea brasiliensis) production in the Amazon has focused on the high-tech practice of double-grafted, leaf blight resistant and high-yielding rubber clones on the one hand, and the low-tech practice of extractive use of natural rubber stands on the other. The intermediate, traditional practice of enriching slash-and-burn plots with rubber trees and managing them in a. secondary forest environment, in association with other timber and non-timber species, has largely been overlooked. We present results from a survey of 51 farmer families conducted on the eastern bank of the Tapajos river in the central Brazilian Amazon, focusing on the population zone of the Tapajos National Forest and its northern vicinity. Actively managed rubber agroforests were most common on the sandy river banks and on humus- and clay-rich and ferralitic soils near the edge of the plateau at a few kilometers from the river. There was a gradient in management intensity between the proximity of the villages at the river, where rubber was often a component of homegardens, and the distant groves on the plateau, which often resembled secondary forests. The spatial separation of access to water at the river and more fertile soils on the plateau, the historical practice of abandoning the rubber groves at times of low rubber prices, and a substantial risk of losing plantations to abiotic and biotic threats, especially fire, are identified as factors that have presumably favored the development of agroforests with low management intensity in the region. Although about half of the interviewed farmers expressed a preference for weeded plantations, almost 90% of them extracted vegetal products other than rubber from the agroforests or used them as hunting grounds, and 80% believed that associated vegetation had no negative influence on rubber yields. The often good health of old rubber trees in Amazonian agroforests is explained with lower pressure from root rots, the periodic abandonment and especially a tapping technique that is well adapted to a moist forest environment. (C) 2003 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{schroth_rubber_2003, author = {Schroth, G. and Coutinho, P. and Moraes, V. H. F. and Albernaz, A. L.}, title = {Rubber agroforests at the Tapajo's river, Brazilian Amazon - environmentally benign land use systems in an old forest frontier region}, journal = {Agriculture Ecosystems & Environment}, year = {2003}, volume = {97}, number = {1-3}, pages = {151--165}, url = {://WOS:000184028800011}, doi = {https://doi.org/10.1016/s0167-8809(03)00116-6} } |
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Schroeder, W., Prins, E., Giglio, L., Csiszar, I., Schmidt, C., Morisette, J. and Morton, D. | Validation of GOES and MODIS active fire detection products using ASTER and ETM plus data | 2008 | Remote Sensing of Environment Vol. 112(5), pp. 2711-2726 |
article | DOI URL |
Abstract: In this study we implemented a comprehensive analysis to validate the MODIS and GOES satellite active fire detection products (MOD 14 and WFABBA, respectively) and characterize their major sources of omission and commission errors which have important implications for a large community of fire data users. Our analyses were primarily based on the use of 30 m resolution ASTER and ETM+ imagery as our validation data. We found that at the 50% true positive detection probability mark, WFABBA requires four times more active fire area than is necessary for MOD14 to achieve the same probability of detection, despite the 16x factor separating the nominal spatial resolutions of the two products. Approximately 75% and 95% of all fires sampled were omitted by the MOD14 and WFABBA instantaneous products, respectively; whereas an omission error of 38% was obtained for WFABBA when considering the 30-minute interval of the GOES data. Commission errors for MOD] 4 and WFABBA were found to be similar and highly dependent on the vegetation conditions of the areas imaged, with the larger commission errors (approximately 35%) estimated over regions of active deforestation. Nonetheless, the vast majority (textgreater80%) of the commission errors were indeed associated with recent burning activity where scars could be visually confirmed in the higher resolution data. Differences in thermal dynamics of vegetated and non-vegetated areas were found to produce a reduction of approximately 50% in the commission errors estimated towards the hours of maximum fire activity (i.e., early-afternoon hours) which coincided with the MODIS/Aqua overpass. Lastly, we demonstrate the potential use of temporal metrics applied to the mid-infrared bands of MODIS and GOES data to reduce the commission errors found with the validation analyses. (C) 2008 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{schroeder_validation_2008, author = {Schroeder, Wilfrid and Prins, Elaine and Giglio, Louis and Csiszar, Ivan and Schmidt, Christopher and Morisette, Jeffrey and Morton, Douglas}, title = {Validation of GOES and MODIS active fire detection products using ASTER and ETM plus data}, journal = {Remote Sensing of Environment}, year = {2008}, volume = {112}, number = {5}, pages = {2711--2726}, url = {://WOS:000255370700061}, doi = {https://doi.org/10.1016/j.rse.2008.01.005} } |
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Schroeder, W., Morisette, J.T., Csiszar, I., Giglio, L., Morton, D. and Justice, C. | Characterizing vegetation fire dynamics in Brazil through multisatellite data: Common trends and practical issues | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Correctly characterizing the frequency and distribution of fire occurrence is essential for understanding the environmental impacts of biomass burning. Satellite fire detection is analyzed from two sensors - the Advanced Very High Resolution Radiometer (AVHRR) on NOAA-12 and the Moderate Resolution Imaging Spectroradiometer ( MODIS) on both the Terra and Aqua platforms, for 2001 - 03 - to characterize fire activity in Brazil, giving special emphasis to the Amazon region. In evaluating the daily fire counts, their dependence on variations in satellite viewing geometry, overpass time, atmospheric conditions, and fire characteristics were considered. Fire counts were assessed for major biomes of Brazil, the nine states of the Legal Amazon, and two important road corridors in the Amazon region. All three datasets provide consistent information on the timing of peak fire activity for a given state. Also, ranking by relative fire counts per unit area highlights the importance of fire in smaller biomes such as Complexo do Pantanal. The local analysis of road corridors shows trends for fire detections with the increasing intensity of land use. Although absolute fire counts differ by as much as 1200%, when summarized over space and time, trends in fire counts among the three datasets show clear patterns of fire dynamics. The fire dynamics that are evident in these trend analyses are important foundations for assessing environmental impacts of biomass burning and policy measures to manage fire in Brazil. | |||||
BibTeX:
@article{schroeder_characterizing_2005, author = {Schroeder, W. and Morisette, J. T. and Csiszar, I. and Giglio, L. and Morton, D. and Justice, C.O.}, title = {Characterizing vegetation fire dynamics in Brazil through multisatellite data: Common trends and practical issues}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241213900001} } |
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Schroeder, W., Csiszar, I. and Morisette, J. | Quantifying the impact of cloud obscuration on remote sensing of active fires in the Brazilian Amazon | 2008 | Remote Sensing of Environment Vol. 112(2), pp. 456-470 |
article | DOI URL |
Abstract: Vegetation fires remain as one of the most important processes governing land use and land cover change in tropical areas. The large area extent of fire prone areas associated with human activities makes satellite remote sensing of active fires a valuable tool to help monitor biomass burning in those regions. However, identification of active fire fronts under optically thick clouds is not possible through passive remote sensing, often resulting in omission errors. Previous analyses of fire activity either ignored the cloud obscuration problem or applied corrections based on the assumption that fire occurrence is not impacted by the presence of clouds. In this study we addressed the cloud obscuration problem in the Brazilian Amazon region using a pixel based probabilistic approach, using information on previous fire occurrence, precipitation and land use. We implemented the methodology using data from the geostationary GOES imager, covering the entire diurnal cycle of fire activity and cloud occurrence. Our assessment of the method indicated that the cloud adjustment reproduced the number of potential fires missed within 1.5% and 5% of the true fire counts on annual and monthly bases respectively. Spatially explicit comparison with high resolution burn scar maps in Acre state showed a reduction of omission error (from 58.3% to 43.7%) and only slight increase of commission error (from 6.4% to 8.8%) compared to uncorrected fire counts. A basin-wide analysis of corrected GOES fire counts during 2005 showed a mean cloud adjustment factor of approximately 11%, ranging from negligible adjustment in the central and western part of the Brazilian Amazon to as high as 50% in parts of Roraima, Para and Mato Grosso. (C) 2007 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{schroeder_quantifying_2008, author = {Schroeder, Wilfrid and Csiszar, Ivan and Morisette, Jeffrey}, title = {Quantifying the impact of cloud obscuration on remote sensing of active fires in the Brazilian Amazon}, journal = {Remote Sensing of Environment}, year = {2008}, volume = {112}, number = {2}, pages = {456--470}, url = {://WOS:000253068100014}, doi = {https://doi.org/10.1016/j.rse.2007.05.004} } |
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Schroeder, W., Alencar, A., Arima, E. and Setzer, A. | The Spatial Distribution and Interannual Variability of Fire in Amazonia [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 43-60 |
incollection | |
BibTeX:
@incollection{m_keller_spatial_2009, author = {Schroeder, Wilfrid and Alencar, Ane and Arima, Eugenio and Setzer, Alberto}, title = {The Spatial Distribution and Interannual Variability of Fire in Amazonia}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {43--60} } |
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Schrod, J., Thomson, E.S., Weber, D., Kossmann, J., Pöhlker, C., Saturno, J., Ditas, F., Artaxo, P., Clouard, V., Saurel, J.M., Ebert, M., Curtius, J. and Bingemer, H.G. | Long-term deposition and condensation ice-nucleating particle measurements from four stations across the globe [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(24), pp. 15983-16006 |
article | DOI URL |
BibTeX:
@article{schrod_long-term_2020, author = {Schrod, J. and Thomson, E. S. and Weber, D. and Kossmann, J. and Pöhlker, C. and Saturno, J. and Ditas, F. and Artaxo, P. and Clouard, V. and Saurel, J. M. and Ebert, M. and Curtius, J. and Bingemer, H. G.}, title = {Long-term deposition and condensation ice-nucleating particle measurements from four stations across the globe}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {24}, pages = {15983--16006}, url = {https://acp.copernicus.org/articles/20/15983/2020/}, doi = {https://doi.org/10.5194/acp-20-15983-2020} } |
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Schor, T. and Alves, D.S. | Ciência, Tecnologia e Sociedade: O Papel das Instituições na Transformação da Ciência e Sociedade – O Caso do LBA [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 35-51 |
incollection | |
BibTeX:
@incollection{batistella_ciencia_2008, author = {Schor, Tatiana and Alves, Diógenes S.}, title = {Ciência, Tecnologia e Sociedade: O Papel das Instituições na Transformação da Ciência e Sociedade – O Caso do LBA}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {35--51}, note = {Section: 1} } |
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Schor, T. | Ciência e tecnologia: o caso do experimento de grande escala da biosfera-atmosfera na Amazônia [BibTeX] |
2008 | Vol. 1(1) |
book | |
BibTeX:
@book{schor_ciencia_2008, author = {Schor, Tatiana}, title = {Ciência e tecnologia: o caso do experimento de grande escala da biosfera-atmosfera na Amazônia}, publisher = {Editora AnnaBlume}, year = {2008}, volume = {1}, number = {1}, note = {Journal Abbreviation: http://www.annablume.com.br/loja/product_info.php?products_id=1034&osCsid=ih6nkjj8p3hr6ii82oqrqtakl7. Publication Title: http://www.annablume.com.br/loja/product_info.php?products_id=1034&osCsid=ih6nkjj8p3hr6ii82oqrqtakl7.} } |
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Schöngart, J., Wittmann, F., Faria de Resende, A., Assahira, C., de Sousa Lobo, G., Rocha Duarte Neves, J., da Rocha, M., Biem Mori, G., Costa Quaresma, A., Oreste Demarchi, L., Weiss Albuquerque, B., Oliveira Feitosa, Y., da Silva Costa, G., Vieira Feitoza, G., Machado Durgante, F., Lopes, A., Trumbore, S.E., Sanna Freire Silva, T., ter Steege, H., Val, A.L., Junk, W.J. and Piedade, M.T.F. | The shadow of the Balbina dam: A synthesis of over 35 years of downstream impacts on floodplain forests in Central Amazonia | 2021 | Aquatic Conservation: Marine and Freshwater Ecosystems Vol. 31(5), pp. 1117-1135 |
article | DOI URL |
Abstract: Abstract The Balbina hydropower dam in the Central Amazon basin, established in the Uatumã River in the 1980s, is emblematic for its socio-environmental disaster. Its environmental impacts go far beyond the reservoir and dam, however, affecting the floodplain forests (igapó) in the downstream area (dam shadow), which have been assessed using a transdisciplinary research approach, synthesized in this review. Floodplain tree species are adapted to a regular and predictable flood pulse, with high- and low-water periods occurring during the year. This was severely affected by the operation of the Balbina dam, which caused the suppression of both the aquatic phase at higher floodplain elevations and the terrestrial phase at lower floodplain elevations (termed the ‘sandwich effect’). During the period of construction and reservoir fill, large-scale mortality already occurred in the floodplains of the dam shadow as a result of reduced stream flow, in synergy with severe drought conditions induced by El Niño events, causing hydraulic failure and making floodplains vulnerable to wildfires. During the operational period of the dam, permanent flooding conditions at low topographical elevations resulted in massive tree mortality. So far, 12% of the igapó forests have died along a downstream river stretch of more than 125 km. As a result of flood suppression at the highest elevations, an encroachment of secondary tree species from upland (terra firme) forests occurred. More than 35 years after the implementation of the Balbina dam, the downstream impacts caused massive losses of macrohabitats, ecosystem services, and diversity of flood-adapted tree species, probably cascading down to the entire food web, which must be considered in conservation management. These findings are discussed critically, emphasizing the urgent need for the Brazilian environmental regulatory agencies to incorporate downstream impacts in the environmental assessments of several dam projects planned for the Amazon region. | |||||
BibTeX:
@article{schongart_shadow_2021, author = {Schöngart, Jochen and Wittmann, Florian and Faria de Resende, Angélica and Assahira, Cyro and de Sousa Lobo, Guilherme and Rocha Duarte Neves, Juliana and da Rocha, Maíra and Biem Mori, Gisele and Costa Quaresma, Adriano and Oreste Demarchi, Layon and Weiss Albuquerque, Bianca and Oliveira Feitosa, Yuri and da Silva Costa, Gilvan and Vieira Feitoza, Gildo and Machado Durgante, Flávia and Lopes, Aline and Trumbore, Susan E. and Sanna Freire Silva, Thiago and ter Steege, Hans and Val, Adalberto Luis and Junk, Wolfgang J. and Piedade, Maria Teresa Fernandez}, title = {The shadow of the Balbina dam: A synthesis of over 35 years of downstream impacts on floodplain forests in Central Amazonia}, journal = {Aquatic Conservation: Marine and Freshwater Ecosystems}, year = {2021}, volume = {31}, number = {5}, pages = {1117--1135}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aqc.3526}, doi = {https://doi.org/10.1002/aqc.3526} } |
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Schongart, J., Junk, W.J., Piedade, M.T.F., Ayres, J.M., Huttermann, A. and Worbes, M. | Teleconnection between tree growth in the Amazonian floodplains and the El Nino-Southern Oscillation effect | 2004 | Global Change Biology Vol. 10(5), pp. 683-692 |
article | DOI URL |
Abstract: There is a limited knowledge about the El Nino-Southern Oscillation (ENSO) effects on the Amazon basin, the world's largest tropical rain forest and a major factor in the global carbon cycle. Seasonal precipitation in the Andean watershed annually causes a several month-long inundation of the floodplains along the Amazon River that induces the formation of annual rings in trees of the flooded forests. Radial growth of trees is mainly restricted to the nonflooded period and thus the ring width corresponds to its duration. This allows the construction of a tree-ring chronology of the long-living hardwood species Piranhea trifoliata Baill. (Euphorbiaceae). El Nino causes anomalously low precipitation in the catchment that results in a significantly lower water discharge of the Amazon River and consequently in an extension of the vegetation period. In those years tree rings are significantly wider. Thus the tree-ring record can be considered as a robust indicator reflecting the mean climate conditions of the whole Western Amazon basin. We present a more than 200-year long chronology, which is the first ENSO-sensitive dendroclimatic proxy of the Amazon basin and permits the dating of preinstrumental El Nino events. Time series analyses of our data indicate that during the last two centuries the severity of El Nino increased significantly. | |||||
BibTeX:
@article{schongart_teleconnection_2004, author = {Schongart, J. and Junk, W. J. and Piedade, M. T. F. and Ayres, J. M. and Huttermann, A. and Worbes, M.}, title = {Teleconnection between tree growth in the Amazonian floodplains and the El Nino-Southern Oscillation effect}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {683--692}, url = {://WOS:000221421600011}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00754.x} } |
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Schneider, J., Freutel, F., Zorn, S.R., Chen, Q., Farmer, D.K., Jimenez, J.L., Martin, S.T., Artaxo, P., Wiedensohler, A. and Borrmann., S. | Mass-spectrometric identification of primary biological particle markers: indication for low abundance of primary biological material in the pristine submicron aerosol of Amazonia [BibTeX] |
2011 | Atmospheric Chemistry and Physics Vol. 11, pp. 11415-11429 |
article | DOI |
BibTeX:
@article{schneider_mass-spectrometric_2011, author = {Schneider, J. and Freutel, F. and Zorn, S. R. and Chen, Q. and Farmer, D. K. and Jimenez, J. L. and Martin, S. T. and Artaxo, P. and Wiedensohler, A. and S., Borrmann.}, title = {Mass-spectrometric identification of primary biological particle markers: indication for low abundance of primary biological material in the pristine submicron aerosol of Amazonia}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, pages = {11415--11429}, doi = {https://doi.org/10.5194/acp-11-11415-2011} } |
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Schmitz, H.J., Amador, R.B., Ferreira, J.E.D., Maués, M.M., Nascimento, I.M.d. and Martins, M.B. | Relações biodiversidade vs. clima em escala local: um estudo de caso em busca de padrões espaço-temporais em insetos [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 19-30 |
incollection | |
BibTeX:
@incollection{emilio_relacoes_2014, author = {Schmitz, Hermes José and Amador, Rosângela Barreto and Ferreira, John Eric Dias and Maués, Márcia Motta and Nascimento, Igor Martins do and Martins, Marlúcia Bonifácio}, title = {Relações biodiversidade vs. clima em escala local: um estudo de caso em busca de padrões espaço-temporais em insetos}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {19--30}, note = {Section: 2} } |
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Schmitt, A.U., Ament, F., de Araújo, A.C., Sá, M. and Teixeira, P. | Modeling atmosphere-land interactions at a rainforest site – a case study using Amazon Tall Tower Observatory (ATTO) measurements and reanalyis data [BibTeX] |
2023 | EGUsphere Vol. 2023, pp. 1-35 |
article | DOI URL |
BibTeX:
@article{schmitt_modeling_2023, author = {Schmitt, A. U. and Ament, F. and de Araújo, A. C. and Sá, M. and Teixeira, P.}, title = {Modeling atmosphere-land interactions at a rainforest site – a case study using Amazon Tall Tower Observatory (ATTO) measurements and reanalyis data}, journal = {EGUsphere}, year = {2023}, volume = {2023}, pages = {1--35}, url = {https://egusphere.copernicus.org/preprints/2023/egusphere-2023-679/}, doi = {https://doi.org/10.5194/egusphere-2023-679} } |
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Schmid, O., Artaxo, P., Arnott, W.P., Chand, D., Gatti, L.V., Frank, G.P., Hoffer, A., Schnaiter, M. and Andreae, M.O. | Spectral light absorption by ambient aerosols influenced by biomass burning in the Amazon Basin. I: Comparison and field calibration of absorption measurement techniques | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 3443-3462 |
article | URL |
Abstract: Spectral aerosol light absorption is an important parameter for the assessment of the radiation budget of the atmosphere. Although on-line measurement techniques for aerosol light absorption, such as the Aethalometer and the Particle Soot Absorption Photometer ( PSAP), have been available for two decades, they are limited in accuracy and spectral resolution because of the need to deposit the aerosol on a filter substrate before measurement. Recently, a 7-wavelength (lambda) Aethalometer became commercially available, which covers the visible (VIS) to near-infrared (NIR) spectral range (lambda = 450 - 950 nm), and laboratory calibration studies improved the degree of confidence in these measurement techniques. However, the applicability of the laboratory calibration factors to ambient conditions has not been investigated thoroughly yet. As part of the LBA-SMOCC ( Large scale Biosphere atmosphere experiment in Amazonia - SMOke aerosols, Clouds, rainfall and Climate) campaign from September to November 2002 in the Amazon basin we performed an extensive field calibration of a 1-lambda PSAP and a 7-lambda Aethalometer utilizing a photoacoustic spectrometer ( PAS, 532 nm) as reference device. Especially during the dry period of the campaign, the aerosol population was dominated by pyrogenic emissions. The most pronounced artifact of integrating-plate type attenuation techniques ( e. g. Aethalometer, PSAP) is due to multiple scattering effects within the filter matrix. For the PSAP, we essentially confirmed the laboratory calibration factor by Bond et al. ( 1999). On the other hand, for the Aethalometer we found a multiple scattering enhancement of 5.23 ( or 4.55, if corrected for aerosol scattering), which is significantly larger than the factors previously reported ( similar to 2) for laboratory calibrations. While the exact reason for this discrepancy is unknown, the available data from the present and previous studies suggest aerosol mixing ( internal versus external) as a likely cause. For Amazonian aerosol, we found no absorption enhancement due to hygroscopic particle growth in the relative humidity (RH) range between 40% and 80%. However, a substantial bias in PSAP sensitivity that correlated with both RH and temperature ( T) was observed for 20%textless RHtextless 30% and 24 degrees Ctextless Ttextless 26 degrees C, respectively. In addition, both PSAP and Aethalometer demonstrated no sensitivity to gaseous adsorption. Although very similar in measurement principle, the PSAP and Aethalometer require markedly different correction factors, which is probably due to the different filter media used. Although on-site calibration of the PSAP and Aethalometer is advisable for best data quality, we recommend a set of "best practice" correction factors for ambient sampling based on the data from the present and previous studies. For this study, the estimated accuracies of the absorption coefficients determined by the PAS, PSAP and Aethalometer were 10, 15 and 20% (95% confidence level), respectively. | |||||
BibTeX:
@article{schmid_spectral_2006, author = {Schmid, O. and Artaxo, P. and Arnott, W. P. and Chand, D. and Gatti, L. V. and Frank, G. P. and Hoffer, A. and Schnaiter, M. and Andreae, M. O.}, title = {Spectral light absorption by ambient aerosols influenced by biomass burning in the Amazon Basin. I: Comparison and field calibration of absorption measurement techniques}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {3443--3462}, url = {://WOS:000239907700005} } |
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Schmale, H., Decesari, S., Henzing, S., Keskinen, B., Sellegri, H., Ovadnevaite, K., Pöhlker, J., M. L., B., Bougiatioti, J., Kristensson, A., Kalivitis, A., Stavroulas, N., Carbone, I., Jefferson, S., Park, A., Schlag, M., Iwamoto, P., Aalto, Y., Äijälä, P., Bukowiecki, M., Ehn, N., Frank, M., Fröhlich, G., Frumau, R., Herrmann, A., Herrmann, E., Holzinger, H., Kos, R., Kulmala, G., Mihalopoulos, M., Nenes, N., O’Dowd, A., Petäjä, C., Picard, T., Pöhlker, D., Pöschl, C., Poulain, U., Prévôt, L., A. S. H., S., Andreae, E., M. O., A., Wiedensohler, P., Ogren, A., Matsuki, J., Yum, A., S. S., S., Baltensperger, F., Gysel, U. and J., M. | Long-term cloud condensation nuclei number concentration, particle number size distribution and chemical composition measurements at regionally representative observatories [BibTeX] |
2018 | Atmospheric Chemistry and Physics Vol. 18(4), pp. 2853-2881 |
article | DOI |
BibTeX:
@article{schmale_long-term_2018, author = {Schmale, Henning, S., Decesari, S., Henzing, B., Keskinen, H., Sellegri, K., Ovadnevaite, J., Pöhlker, M. L., Brito, J., Bougiatioti, A., Kristensson, A., Kalivitis, N., Stavroulas, I., Carbone, S., Jefferson, A., Park, M., Schlag, P., Iwamoto, Y., Aalto, P., Äijälä, M., Bukowiecki, N., Ehn, M., Frank, G., Fröhlich, R., Frumau, A., Herrmann, E., Herrmann, H., Holzinger, R., Kos, G., Kulmala, M., Mihalopoulos, N., Nenes, A., O’Dowd, C., Petäjä, T., Picard, D., Pöhlker, C., Pöschl, U., Poulain, L., Prévôt, A. S. H., Swietlicki, E., Andreae, M. O., Artaxo, P., Wiedensohler, A., Ogren, J., Matsuki, A., Yum, S. S., Stratmann, F., Baltensperger, U., Gysel, M., J.}, title = {Long-term cloud condensation nuclei number concentration, particle number size distribution and chemical composition measurements at regionally representative observatories}, journal = {Atmospheric Chemistry and Physics}, year = {2018}, volume = {18}, number = {4}, pages = {2853--2881}, doi = {https://doi.org/10.5194/acp-18-2853-2018} } |
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Schkolnik, G., Falkovich, A.H., Rudich, Y., Maenhaut, W. and Artaxo, P. | New analytical method for the determination of levoglucosan, polyhydroxy compounds, and 2-methylerythritol and its application to smoke and rainwater samples | 2005 | Environmental Science & Technology Vol. 39(8), pp. 2744-2752 |
article | DOI URL |
Abstract: Biomass burning is an important source of smoke aerosol particles, which contain water-soluble inorganic and organic species, and thus have a great potential of affecting cloud formation, precipitation, and climate on global and regional scales. In this study, we have developed a new chromatographic method for the determination of levoglucosan (a specific tracer for biomass burning particles), related polyhydroxy compounds, and 2-methylerythritol (recently identified as isoprene oxidation product in fine aerosols in the Amazon) in smoke and in rainwater samples. The new method is based on water extraction and utilizes ion-exclusion high-performance liquid chromatography (IEC-HPLC) separation and spectroscopic detection at 194 nm. The new method allows the analysis of wet samples, such as rainwater samples. In addition, aliquots of the same extracts can be used for further analyses, such as ion chromatography. The overall method uncertainty for sample analysis is 15%. The method was applied to the analysis of high-volume and size-segregated smoke samples and to rainwater samples, all collected during and following the deforestation fires season in Rondonia, Brazil. From the analysis of size-segregated samples, it is evident that levoglucosan is a primary vegetation combustion product, emitted mostly in the 0.175-1 mu m size bins. Levoglucosan concentrations decrease below the detection limit at the end of the deforestation fires period, implying that it is not present in significant amounts in background Amazon forest aerosols. The ratio of daytime levoglucosan concentration to particulate matter (PM) concentration was about half the nighttime ratio. This observation is rationalized by the prevalence of flaming combustion during day as opposed to smoldering combustion during night. This work broadens the speciation possibilities offered by simple HPLC and demonstrates the importance of multianalysis of several kinds of samples for a deeper understanding of biomass burning aerosols. | |||||
BibTeX:
@article{schkolnik_new_2005, author = {Schkolnik, G. and Falkovich, A. H. and Rudich, Y. and Maenhaut, W. and Artaxo, P.}, title = {New analytical method for the determination of levoglucosan, polyhydroxy compounds, and 2-methylerythritol and its application to smoke and rainwater samples}, journal = {Environmental Science & Technology}, year = {2005}, volume = {39}, number = {8}, pages = {2744--2752}, note = {Edition: 2005/05/12}, url = {://WOS:000228428900049}, doi = {https://doi.org/10.1021/es048363c} } |
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Schkolnik, G., Chand, D., Hoffer, A., Andreae, M.O., Erlick, C., Swietlicki, E. and Rudich, Y. | Constraining the density and complex refractive index of elemental and organic carbon in biomass burning aerosol using optical and chemical measurements | 2007 | Atmospheric Environment Vol. 41(5), pp. 1107-1118 |
article | DOI URL |
Abstract: The role of biomass burning aerosols in the climate system is still poorly quantified, in part due to uncertainties regarding the optical properties of elemental and organic carbon (EC and OC, respectively), the main constituents of pyrogenic aerosols. In this study, we utilize comprehensive physical and chemical field measurements of biomass burning aerosols in Brazil to constrain the densities and refractive indices (RI) of EC and OC in these particles, by comparing their optically and chemically derived RI. The optically derived effective RI are retrieved from the measured absorption and scattering coefficients using a Mie scattering algorithm, and serve as a reference dataset, while the chemically derived effective RI are calculated from the measured chemical composition using electromagnetic mixing rules. The results are discussed in light of the observed combustion conditions, and in an effort to derive conclusions as to the chemical and optical properties of the usually less well-characterized components of biomass burning aerosols, namely, elemental carbon and organic matter. The best agreement between the optically and chemically derived RI was achieved by assigning a density of rho(EC) = 1.8 g cm(-3) and refractive index RIEC = 1.87 - 0.22i to the EC component, and rho = 0.9 g cm(-3) and RI = 1.4 - 0i to the unidentified organic matter fraction of the particles. These parameters suggest low graphitization levels for the EC, and a dominant proportion of aliphatic compounds in the unidentified organic matter. Combining the density and RI of the unidentified organic matter with the properties of the chemically characterized organic fraction yields rho = 1.1 g cm(-3) and RI = 1.3 - 0i for the total aerosol OC. (c) 2006 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{schkolnik_constraining_2007, author = {Schkolnik, G. and Chand, D. and Hoffer, A. and Andreae, M. O. and Erlick, C. and Swietlicki, E. and Rudich, Y.}, title = {Constraining the density and complex refractive index of elemental and organic carbon in biomass burning aerosol using optical and chemical measurements}, journal = {Atmospheric Environment}, year = {2007}, volume = {41}, number = {5}, pages = {1107--1118}, url = {://WOS:000244329800017}, doi = {https://doi.org/10.1016/j.atmosenv.2006.09.035} } |
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Schiro, K.A.e.a. | Deep Convection and Column Water Vapor over Tropical Land versus Tropical Ocean: A Comparison between the Amazon and the Tropical Western Pacific [BibTeX] |
2016 | Journal of the atmospheric sciences Vol. 73, pp. 4043-4063 |
article | DOI |
BibTeX:
@article{schiro_deep_2016, author = {Schiro, K. A. et al.}, title = {Deep Convection and Column Water Vapor over Tropical Land versus Tropical Ocean: A Comparison between the Amazon and the Tropical Western Pacific}, journal = {Journal of the atmospheric sciences}, year = {2016}, volume = {73}, pages = {4043--4063}, doi = {https://doi.org/10.1175/JAS-D-16-0119.1} } |
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Schimel, D.S. | The large-scale biosphere-atmosphere experiment in the Amazon [BibTeX] |
2004 | Ecological Applications Vol. 14(4), pp. S1-S2 |
article | URL |
BibTeX:
@article{schimel_large-scale_2004, author = {Schimel, D. S.}, title = {The large-scale biosphere-atmosphere experiment in the Amazon}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S1--S2}, url = {://WOS:000223269000001} } |
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Schietti, D., Emilio, T., Souza, P., Levis, C., Baccaro, F., Pinto, J., moulatlet , G., Stark, S., Sarmento, K., de Araújo, R., Costa, F., Schöngart, J., Quesada, C., Saleska, S., Tomasella, J., Magnusson WE., J. and Martins | Forest structure along a 600 km transect of natural disturbances and seasonality gradients in central-southern Amazonia [BibTeX] |
2016 | Journal of Ecology Vol. 104, pp. 1335-1346 |
article | |
BibTeX:
@article{schietti_forest_2016, author = {Schietti, D; Emilio, T; Souza, PF; Levis, C; Baccaro, F; Pinto, JLPV; moulatlet, GM; Stark, SC; Sarmento, K; de Araújo, RNO; Costa, FRC; Schöngart, J; Quesada, CA; Saleska, SR; Tomasella, J; Magnusson, WE., J; Martins}, title = {Forest structure along a 600 km transect of natural disturbances and seasonality gradients in central-southern Amazonia}, journal = {Journal of Ecology}, year = {2016}, volume = {104}, pages = {1335--1346} } |
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Schietti, J., Emilio, T., Rennó, C.D., Drucker, D.P., Costa, F.R., Nogueira, A., Baccaro, F.B., Figueiredo, F., Castilho, C.V., Kinupp, V., Guillaumet, J.-L., Garcia, A.R.M., Lima, A.P. and Magnusson, W.E. | Vertical distance from drainage drives floristic composition changes in an Amazonian rainforest [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 241-253 |
article | |
BibTeX:
@article{schietti_vertical_2014, author = {Schietti, Juliana and Emilio, Thaise and Rennó, Camilo D. and Drucker, Debora P. and Costa, Flávia R.C. and Nogueira, Anselmo and Baccaro, Fabricio B. and Figueiredo, Fernando and Castilho, Carolina V. and Kinupp, Valdely and Guillaumet, Jean-Louis and Garcia, Ana Raquel M. and Lima, Albertina P. and Magnusson, William E.}, title = {Vertical distance from drainage drives floristic composition changes in an Amazonian rainforest}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {241--253} } |
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Scheffler, R., Neill, C., Krusche, A.V. and Elsenbeer, H. | Soil hydraulic response to land-use change associated with the recent soybean expansion at the Amazon agricultural frontier | 2011 | Agriculture Ecosystems & Environment Vol. 144(1), pp. 281-289 |
article | DOI URL |
Abstract: Clearing for large-scale soy production and the displacement of cattle-breeding by soybeans are major features of land-use change in the lowland Amazon that can alter hydrologic properties of soils and the runoff generation over large areas. We measured infiltrability and saturated hydraulic conductivity (Ksat) under natural forest, pasture, and soybeans on Oxisols in a region of rapid soybean expansion in Mato Grosso, Brazil. The forest-pasture conversion reduced infiltrability from 1258 to 100 mm/h and Ksat at all depths. The pasture-soy conversion increased infiltrability from 100 to 469 mm/h (attributed to shallow disking), did not affect Ksat at 12.5 cm, but decreased Ksat at 30 cm from 122 to 80 mm/h, suggesting that soybean cultivation enhances subsoil compaction. Permeability decreased markedly with depth under forest, did not change under pasture, and averaged out at one fourth the forest value under soybeans with a similar pattern of anisotropy. Comparisons of permeability with rainfall intensities indicated that land-use change did not alter the predominantly vertical water movement within the soil. We conclude that this landscape is well buffered against land-use changes regarding near-surface hydrology, even though short-lived ponding and perched water tables may occur locally during high-intensity rainfall on pastures and under soybeans. (C) 2011 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{scheffler_soil_2011, author = {Scheffler, Raphael and Neill, Christopher and Krusche, Alex V. and Elsenbeer, Helmut}, title = {Soil hydraulic response to land-use change associated with the recent soybean expansion at the Amazon agricultural frontier}, journal = {Agriculture Ecosystems & Environment}, year = {2011}, volume = {144}, number = {1}, pages = {281--289}, url = {://WOS:000298898200030}, doi = {https://doi.org/10.1016/j.agee.2011.08.016} } |
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Schafer, J.S., Holben, B.N., Eck, T.F., Yamasoe, M.A. and Artaxo, P. | Atmospheric effects on insolation in the Brazilian Amazon: Observed modification of solar radiation by clouds and smoke and derived single scattering albedo of fire aerosols | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Five aerosol and solar flux monitoring sites were established in Brazil for the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. The first two sites were developed in the states of Rondonia and Mato Grosso in January 1999, while the others were initiated in September 1999 in Amazonas, Para, and near Brasilia (later relocated to Acre). Daily insolation [photosynthetically active radiation (PAR) and total solar] for 1999 and 9 months of 2000 was determined from flux measurements, and the daily fraction of theoretical cloud-free, background-aerosol insolation, f(B(day)), was evaluated for each site. Observed daily shortfall (MJ m(-2) d(-1)) of PAR insolation due to clouds and aerosols (relative to modeled values for background aerosol), and the instantaneous reductions of PAR irradiance due to high aerosol optical thickness (AOT) smoke events are presented for 1999 at Alta Floresta. The ratio of PAR flux to total solar flux (PAR fraction) was examined for all atmospheric conditions during 1999, and the observed dependence of this parameter on column water vapor and smoke AOT was quantified. No significant relationship with cloud amount (as quantified) was found. Instantaneous PAR irradiance measurements and concurrent, cloud-cleared aerosol data from collocated CIMEL sunphotometers were used with a radiative transfer model to investigate the optical properties of smoke aerosols during the burning season. In particular, the single scattering albedo (SSA) was evaluated in the PAR spectral range for AOT(440 nm) values ranging from 0.8 to 3.0. These estimates were compared with the operational retrievals of the same parameter from algorithms developed by AERONET for CIMEL sunphotometer radiance measurements. | |||||
BibTeX:
@article{schafer_atmospheric_2002, author = {Schafer, J. S. and Holben, B. N. and Eck, T. F. and Yamasoe, M. A. and Artaxo, P.}, title = {Atmospheric effects on insolation in the Brazilian Amazon: Observed modification of solar radiation by clouds and smoke and derived single scattering albedo of fire aerosols}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200035 http://www.agu.org/journals/jd/jd0217/2001JD000428/2001JD000428.pdf}, doi = {https://doi.org/10.1029/2001jd000428} } |
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Schafer, J.S., Eck, T.F., Holben, B.N., Artaxo, P., Yamasoe, M.A. and Procopio, A.S. | Observed reductions of total solar irradiance by biomass-burning aerosols in the Brazilian Amazon and Zambian Savanna | 2002 | Geophysical Research Letters Vol. 29(17), pp. 1823-1826 |
article | DOI URL |
Abstract: [1] Several aerosol and solar flux monitoring sites were established in Brazil for the Large Scale Biosphere-Atmosphere Experiment in Amazonia project. CIMEL sunphotometers and collocated pyranometers were employed at two southern Amazonian sites in order to quantify instantaneous reductions of total irradiance due to high aerosol optical thickness (AOT) smoke events (relative to values modeled for background aerosol conditions). Results from the Brazilian sites are presented for 1999 and for comparison, a similar analysis is discussed for data from three south-central African sites during the burning season of 2000. The relative reductions in total irradiance at the surface resulting from biomass burning aerosol are observed to be substantial at all sites, ranging from 16% for an aerosol optical thickness (500 nm) of 1.0 for the Brazilian sites to an average rate of 22% for the African sites. For a solar zenith interval (25-35degrees), these rates equate to reductions of roughly 145 W/m(2) and 210 W/m(2) respectively, for an AOT = 1.0. Instantaneous reductions of 337 W/m(2) were observed for the heaviest smoke conditions (AOT: similar to3.0) in Brazil. | |||||
BibTeX:
@article{schafer_observed_2002, author = {Schafer, J. S. and Eck, T. F. and Holben, B. N. and Artaxo, P. and Yamasoe, M. A. and Procopio, A. S.}, title = {Observed reductions of total solar irradiance by biomass-burning aerosols in the Brazilian Amazon and Zambian Savanna}, journal = {Geophysical Research Letters}, year = {2002}, volume = {29}, number = {17}, pages = {1823--1826}, url = {://WOS:000180397500004}, doi = {https://doi.org/10.1029/2001gl014309} } |
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Schafer, J.S., Eck, T.F., Holben, B.N., Artaxo, P. and Duarte, A.F. | Characterization of the optical properties of atmospheric aerosols in Amazonia from long-term AERONET monitoring (1993-1995 and 1999-2006) | 2008 | Journal of Geophysical Research-Atmospheres Vol. 113(D4) |
article | DOI URL |
Abstract: We present a new climatology of atmospheric aerosols (primarily pyrogenic and biogenic) for the Brazilian tropics on the basis of a high-quality data set of spectral aerosol optical depth and directional sky radiance measurements from Aerosol Robotic Network (AERONET) Cimel Sun-sky radiometers at more than 15 sites distributed across the Amazon basin and adjacent Cerrado region. This network is the only long-term project (with a record including observations from more than 11 years at some locations) ever to have provided ground-based remotely-sensed column aerosol properties for this critical region. Distinctive features of the Amazonian area aerosol are presented by partitioning the region into three aerosol regimes: southern Amazonian forest, Cerrado, and northern Amazonian forest. The monitoring sites generally include measurements from the interval 1999-2006, but some sites have measurement records that date back to the initial days of the AERONET program in 1993. Seasonal time series of aerosol optical depth (AOD), angstrom ngstrom exponent, and columnar-averaged microphysical properties of the aerosol derived from sky radiance inversion techniques (single-scattering albedo, volume size distribution, fine mode fraction of AOD, etc.) are described and contrasted for the defined regions. During the wet season, occurrences of mineral dust penetrating deep into the interior were observed. | |||||
BibTeX:
@article{schafer_characterization_2008, author = {Schafer, J. S. and Eck, T. F. and Holben, B. N. and Artaxo, P. and Duarte, A. F.}, title = {Characterization of the optical properties of atmospheric aerosols in Amazonia from long-term AERONET monitoring (1993-1995 and 1999-2006)}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2008}, volume = {113}, number = {D4}, url = {://WOS:000253531600002 http://www.agu.org/journals/jd/jd0804/2007JD009319/2007JD009319.pdf}, doi = {https://doi.org/10.1029/2007jd009319} } |
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Schaap, K.J., Fuchslueger, L., Quesada, C.A., Hofhansl, F., Valverde-Barrantes, O., Camargo, P.B. and Hoosbeek, M.R. | Seasonal fluctuations of extracellular enzyme activities are related to the biogeochemical cycling of C, N and P in a tropical terra-firme forest | 2023 | Biogeochemistry | article | DOI URL |
Abstract: Extracellular enzymes (EE) play a vital role in soil nutrient cycling and thus affect terrestrial ecosystem functioning. Yet the drivers that regulate microbial activity, and therefore EE activity, remain under debate. In this study we investigate the temporal variation of soil EE in a tropical terra-firme forest. We found that EE activity peaked during the drier season in association with increased leaf litterfall, which was also reflected in negative relationships between EE activities and precipitation. Soil nutrients were weakly related to EE activities, although extractable N was related to EE activities in the top 5 cm of the soil. These results suggest that soil EE activity is synchronized with precipitation-driven substrate inputs and depends on the availability of N. Our results further indicate high investments in P acquisition, with a higher microbial N demand in the month before the onset of the drier season, shifting to higher P demand towards the end of the drier season. These seasonal fluctuations in the potential acquisition of essential resources imply dynamic shifts in microbial activity in coordination with climate seasonality and resource limitation of central-eastern Amazon forests. | |||||
BibTeX:
@article{schaap_seasonal_2023, author = {Schaap, Karst J. and Fuchslueger, Lucia and Quesada, Carlos Alberto and Hofhansl, Florian and Valverde-Barrantes, Oscar and Camargo, Plínio B. and Hoosbeek, Marcel R.}, title = {Seasonal fluctuations of extracellular enzyme activities are related to the biogeochemical cycling of C, N and P in a tropical terra-firme forest}, journal = {Biogeochemistry}, year = {2023}, url = {https://doi.org/10.1007/s10533-022-01009-4}, doi = {https://doi.org/10.1007/s10533-022-01009-4} } |
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Schaap, K.J., Fuchslueger, L., Hoosbeek, M.R., Hofhansl, F., Martins, N.P., Valverde-Barrantes, O.J., Hartley, I.P., Lugli, L.F. and Quesada, C.A. | Litter inputs and phosphatase activity affect the temporal variability of organic phosphorus in a tropical forest soil in the Central Amazon | 2021 | Plant and Soil Vol. 469(1), pp. 423-441 |
article | DOI URL |
Abstract: The tropical phosphorus cycle and its relation to soil phosphorus (P) availability are a major uncertainty in projections of forest productivity. In highly weathered soils with low P concentrations, plant and microbial communities depend on abiotic and biotic processes to acquire P. We explored the seasonality and relative importance of drivers controlling the fluctuation of common P pools via processes such as litter production and decomposition, and soil phosphatase activity. | |||||
BibTeX:
@article{schaap_litter_2021, author = {Schaap, Karst J. and Fuchslueger, Lucia and Hoosbeek, Marcel R. and Hofhansl, Florian and Martins, Nathielly Pires and Valverde-Barrantes, Oscar J. and Hartley, Iain P. and Lugli, Laynara F. and Quesada, Carlos Alberto}, title = {Litter inputs and phosphatase activity affect the temporal variability of organic phosphorus in a tropical forest soil in the Central Amazon}, journal = {Plant and Soil}, year = {2021}, volume = {469}, number = {1}, pages = {423--441}, url = {https://doi.org/10.1007/s11104-021-05146-x}, doi = {https://doi.org/10.1007/s11104-021-05146-x} } |
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Sawakuchi, H.O., Neu, V., Ward, N.D., Barros, M.d.L.C., Valerio, A.M., Gagne-Maynard, W., Cunha, A.C., Less, D.F.S., Diniz, J.E.M., Brito, D.C., Krusche, A.V. and Richey, J.E. | Carbon Dioxide Emissions along the Lower Amazon River [BibTeX] |
2017 | Frontiers in Marine Science Vol. 4, pp. 1-12 |
article | |
BibTeX:
@article{sawakuchi_carbon_2017, author = {Sawakuchi, H. O. and Neu, V. and Ward, Nicholas D. and Barros, Maria de Lourdes C. and Valerio, A. M. and Gagne-Maynard, William and Cunha, Alan C. and Less, Diani F. S. and Diniz, Joel E. M. and Brito, Daimio C. and Krusche, A. V. and Richey, Jeffrey E.}, title = {Carbon Dioxide Emissions along the Lower Amazon River}, journal = {Frontiers in Marine Science}, year = {2017}, volume = {4}, pages = {1--12} } |
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Sawakuchi, H., Bastviken, D., Sawakuchi, A., Ward, N., Borges, C., Tsai, S., Richey, J.E., Ballester, M. and Krusche, A. | Oxidative mitigation of aquatic methane emissions in large Amazonian rivers [BibTeX] |
2016 | Global Change Biology Vol. 22(3), pp. 1075-1085 |
article | |
BibTeX:
@article{sawakuchi_oxidative_2016, author = {Sawakuchi, H.O. and Bastviken, D. and Sawakuchi, A.O. and Ward, N.D. and Borges, C.D. and Tsai, S.M. and Richey, J. E. and Ballester, M.V.R. and Krusche, A.V.}, title = {Oxidative mitigation of aquatic methane emissions in large Amazonian rivers}, journal = {Global Change Biology}, year = {2016}, volume = {22}, number = {3}, pages = {1075--1085} } |
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Sawakuchi, H.O., Bastviken, D., Sawakuchi, A., Krusche, A.V., Ballester, M.V.R. and Richey, J.E. | Methane emissions from Amazonian Rivers and their contribution to the global methane budget [BibTeX] |
2014 | Global Change Biology Vol. 20, pp. 2829-2840 |
article | DOI |
BibTeX:
@article{sawakuchi_methane_2014, author = {Sawakuchi, Henrique O. and Bastviken, D. and Sawakuchi, A. and Krusche, Alex V. and Ballester, Maria V. R. and Richey, Jeffrey E.}, title = {Methane emissions from Amazonian Rivers and their contribution to the global methane budget}, journal = {Global Change Biology}, year = {2014}, volume = {20}, pages = {2829--2840}, doi = {https://doi.org/10.1111/gcb.12646} } |
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Satyamurty, P., de Castro, A.A., Tota, J., da Silva Gularte, L.E. and Manzi, A.O. | Rainfall trends in the Brazilian Amazon Basin in the past eight decades | 2010 | Theoretical and Applied Climatology Vol. 99(1-2), pp. 139-148 |
article | DOI URL |
Abstract: Rainfall series at 18 stations along the major rivers of the Brazilian Amazon Basin, having data since 1920s or 1930s, are analyzed to verify if there are appreciable long-term trends. Annual, rainy-season, and dry-season rainfalls are individually analyzed for each station and for the region as a whole. Some stations showed positive trends and some negative trends. The trends in the annual rainfall are significant at only six stations, five of which reporting increasing trends (Barcelos, Belem, Manaus, Rio Branco, and Soure stations) and just one (Itaituba station) reporting decreasing trend. The climatological values of rainfall before and after 1970 show significant differences at six stations (Barcelos, Belem, Benjamin Constant, Iaurete, Itaituba, and Soure). The region as a whole shows an insignificant and weak downward trend; therefore, we cannot affirm that the rainfall in the Brazilian Amazon basin is experiencing a significant change, except at a few individual stations. Subregions with upward and downward trends are interspersed in space from the far eastern Amazon to western Amazon. Most of the seasonal trends follow the annual trends, thus, indicating a certain consistency in the datasets and analysis. | |||||
BibTeX:
@article{satyamurty_rainfall_2010, author = {Satyamurty, Prakki and de Castro, Aline Anderson and Tota, Julio and da Silva Gularte, Lucia Eliane and Manzi, Antonio Ocimar}, title = {Rainfall trends in the Brazilian Amazon Basin in the past eight decades}, journal = {Theoretical and Applied Climatology}, year = {2010}, volume = {99}, number = {1-2}, pages = {139--148}, url = {://WOS:000271738600012}, doi = {https://doi.org/10.1007/s00704-009-0133-x} } |
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Satyamurty, P., da Costa, C.P.W., Manzi, A. and Candido, L.A. | A quick look at the 2012 record flood in the Amazon Basin [BibTeX] |
2013 | Geophysical Research Letters Vol. 40, pp. 1/1-6 |
article | |
BibTeX:
@article{satyamurty_quick_2013, author = {Satyamurty, P. and da Costa, C. P. W. and Manzi, A.O. and Candido, L. A.}, title = {A quick look at the 2012 record flood in the Amazon Basin}, journal = {Geophysical Research Letters}, year = {2013}, volume = {40}, pages = {1/1--6} } |
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Satyamurty, P., Costa, C.W. and Manzi, A. | Moisture source for the Amazon Basin: a study of contrasting years [BibTeX] |
2013 | Theoretical and Applied Climatology Vol. 111, pp. 195-209 |
article | |
BibTeX:
@article{satyamurty_moisture_2013, author = {Satyamurty, P. and Costa, C.P. W. and Manzi, A.O.}, title = {Moisture source for the Amazon Basin: a study of contrasting years}, journal = {Theoretical and Applied Climatology}, year = {2013}, volume = {111}, pages = {195--209} } |
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Saturno, J., Holanda, B.A., Pöhlker, C., Ditas, F., Wang, Q., Moran-Zuloaga, D., Brito, J., Carbone, S., Cheng, Y., Chi, X., Ditas, J., Hoffmann, T., Hrabe de Angelis, I., Könemann, T., Lavrič, J.V., Ma, N., Ming, J., Paulsen, H., Pöhlker, M.L., Rizzo, L.V., Schlag, P., Su, H., Walter, D., Wolff, S., Zhang, Y., Artaxo, P., Pöschl, U. and Andreae, M.O. | Black and brown carbon over central Amazonia: long-term aerosol measurements at the ATTO site [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18(17), pp. 12817-12843 |
article | DOI URL |
BibTeX:
@article{saturno_black_2018, author = {Saturno, J. and Holanda, B. A. and Pöhlker, C. and Ditas, F. and Wang, Q. and Moran-Zuloaga, D. and Brito, J. and Carbone, S. and Cheng, Y. and Chi, X. and Ditas, J. and Hoffmann, T. and Hrabe de Angelis, I. and Könemann, T. and Lavrič, J. V. and Ma, N. and Ming, J. and Paulsen, H. and Pöhlker, M. L. and Rizzo, L. V. and Schlag, P. and Su, H. and Walter, D. and Wolff, S. and Zhang, Y. and Artaxo, P. and Pöschl, U. and Andreae, M. O.}, title = {Black and brown carbon over central Amazonia: long-term aerosol measurements at the ATTO site}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, number = {17}, pages = {12817--12843}, url = {https://acp.copernicus.org/articles/18/12817/2018/}, doi = {https://doi.org/10.5194/acp-18-12817-2018} } |
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Saturno Pöhlker, C.M.D.B.J.C.S.C.Y.C.X.D.F.H.d.A.I.M.-Z.D.P.M.L.R.L.V.W.D.W.Q.A.P.P.P.A.M.O.J. | Comparison of different Aethalometer correction schemes and a reference multi-wavelength technique for ambient aerosol data. [BibTeX] |
2017 | Atmospheric Measurement Techniques Vol. 10, pp. 2837-2850 |
article | |
BibTeX:
@article{saturno_comparison_2017, author = {Saturno, Pöhlker, C., Massabò, D., Brito, J., Carbone, S., Cheng, Y., Chi, X., Ditas, F., Hrabe de Angelis, I., Morán-Zuloaga, D., Pöhlker, M. L., Rizzo, L. V., Walter, D. Wang. Q., Artaxo, P., Prati. P., Andreae, M. O, J.}, title = {Comparison of different Aethalometer correction schemes and a reference multi-wavelength technique for ambient aerosol data.}, journal = {Atmospheric Measurement Techniques}, year = {2017}, volume = {10}, pages = {2837--2850} } |
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Sarkar, C., Guenther, A.B., Park, J.H., Seco, R., Alves, E., Batalha, S., Santana, R., Kim, S., Smith, J., Tóta, J. and Vega, O. | PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(12), pp. 7179-7191 |
article | DOI URL |
BibTeX:
@article{sarkar_ptr-tof-ms_2020, author = {Sarkar, C. and Guenther, A. B. and Park, J. H. and Seco, R. and Alves, E. and Batalha, S. and Santana, R. and Kim, S. and Smith, J. and Tóta, J. and Vega, O.}, title = {PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {12}, pages = {7179--7191}, url = {https://acp.copernicus.org/articles/20/7179/2020/}, doi = {https://doi.org/10.5194/acp-20-7179-2020} } |
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Sapucci, L.F., Machado, L.A.T., Monico, J.F.G. and Plana-Fattori, A. | Intercomparison of integrated water vapor estimates from multisensors in the amazonian region | 2007 | Journal of Atmospheric and Oceanic Technology Vol. 24(11), pp. 1880-1894 |
article | DOI URL |
Abstract: Water vapor is an atmospheric component of major interest in atmospheric science because it affects the energy budget and plays a key role in several atmospheric processes. The Amazonian region is one of the most humid on the planet, and land use change is able to affect the hydrologic cycle in several areas and consequently to generate severe modifications in the global climate. Within this context, accessing the error associated with atmospheric humidity measurement and the validation of the integrated water vapor (IWV) quantification from different techniques is very important in this region. Using data collected during the Radiation, Cloud, and Climate Interactions in Amazonia during the Dry-to-Wet Transition Season (RACCI/DRY-TO-WET), an experiment carried out in southwestern Amazonia in 2002, this paper presents quality analysis of IWV measurements from RS80 radiosondes, a suite of GPS receivers, an Aerosol Robotic Network (AERONET) solar radiometer, and humidity sounding from the Humidity Sounder for Brazil (HSB) aboard the Aqua satellite. When compared to RS80 IWV values, the root-mean-square (RMS) from the AERONET and GPS results are of the order of 2.7 and 3.8 kg m(-2), respectively. The difference generated between IWV from the GPS receiver and RS80 during the daytime was larger than that of the nighttime period because of the combination of the influence of high ionospheric activity during the RACCI experiment and a daytime drier bias from the RS80. | |||||
BibTeX:
@article{sapucci_intercomparison_2007, author = {Sapucci, Luiz F. and Machado, Luiz A. T. and Monico, Joao F. G. and Plana-Fattori, Artemio}, title = {Intercomparison of integrated water vapor estimates from multisensors in the amazonian region}, journal = {Journal of Atmospheric and Oceanic Technology}, year = {2007}, volume = {24}, number = {11}, pages = {1880--1894}, url = {://WOS:000251121300004}, doi = {https://doi.org/10.1175/jtech2090.1} } |
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Sapucci, L.F., Machado, L.A.T., da Silveira, R.B., Fisch, G. and Monico, J.F.G. | Analysis of relative humidity sensors at the WMO Radiosonde intercomparison experiment in Brazil | 2005 | Journal of Atmospheric and Oceanic Technology Vol. 22(6), pp. 664-678 |
article | DOI URL |
Abstract: The quality of the vertical distribution measurements of humidity in the atmosphere is very important in meteorology due to the crucial role that water vapor plays in the earth's energy budget. The radiosonde is the humidity measurement device that provides the best vertical resolution. Also, radiosondes are the operational devices that are used to measure the vertical profile of atmospheric water vapor. The World Meteorological Organization (WMO) has carried out several intercomparison experiments at different climatic zones in order to identify the differences between the available commercial sensors. This article presents the results of an experiment that was carried out in Brazil in 2001 in which major commercial radiosonde manufacturers [e.g., Graw Radiosondes GmbH & Co., KG (Germany); MODEM (France); InterMet Systems (United States); Sippican, Inc. (United States); and Vaisala (Finland)] were involved. One of the main goals of this experiment was to evaluate the performance of the different humidity sensors in a tropical region. This evaluation was performed for different atmospheric layers and distinct periods of the day. It also considers the computation of the integrated water vapor (IWV). The results showed that the humidity measurements achieved by the different sensors were quite similar in the low troposphere (the bias median value regarding the RS80 was around 1.8%) and were quite dispersed in the superior layers (the median rms regarding the RS80 was around 14.9%). | |||||
BibTeX:
@article{sapucci_analysis_2005, author = {Sapucci, L. F. and Machado, L. A. T. and da Silveira, R. B. and Fisch, G. and Monico, J. F. G.}, title = {Analysis of relative humidity sensors at the WMO Radiosonde intercomparison experiment in Brazil}, journal = {Journal of Atmospheric and Oceanic Technology}, year = {2005}, volume = {22}, number = {6}, pages = {664--678}, url = {://WOS:000230140600004 http://journals.ametsoc.org/doi/pdf/10.1175/JTECH1754.1}, doi = {https://doi.org/10.1175/jtech1754.1} } |
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Sapucci, L.F., Galera Monico, J.F., Toledo Machado, L.A. and Dos Santos Rosa, G.P. | Evaluation of zenithal tropospheric delay predictions for South America from high spatial resolution numerical weather prediction model | 2008 | Boletim De Ciencias Geodesicas Vol. 14(4), pp. 591-605 |
article | URL |
Abstract: A Center for Weather Forecast and Climatic Studies of National Institute for Space Research (CPTEC/INPE) has provided to the Brazilian Geodetic community, since 2004, an alternative to correct the GNSS observables from the tropospheric refraction. Numerical Weather Prediction (NWP) Model is used to generate Zenital Tropospheric Delay (ZTD). For the version 1, it was developed a model with horizontal resolution of 100 km, which was updated with Eta model, with resolution of 20 km. This paper provides the most significative details of the current version, as well an evaluation of its quality, using for such ZTD estimates from GPS data collect at RBMC. Comparing to the old version, considerable improvement could be observed from the new model, mainly in Brasilia and Curitiba, reaching up to 55% improvement. When all stations were used in the quality control, almost null bias and RMS of about 4 to 5 cm could be observed. | |||||
BibTeX:
@article{sapucci_evaluation_2008, author = {Sapucci, Luiz Fernando and Galera Monico, Joao Francisco and Toledo Machado, Luiz Augusto and Dos Santos Rosa, Guilherme Poleszuk}, title = {Evaluation of zenithal tropospheric delay predictions for South America from high spatial resolution numerical weather prediction model}, journal = {Boletim De Ciencias Geodesicas}, year = {2008}, volume = {14}, number = {4}, pages = {591--605}, url = {://WOS:000264127500008} } |
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Santos, V.A.H.F.d., Nelson, B.W., Rodrigues, J.V.F.C., Garcia, M.N., Ceron, J.V.B. and Ferreira, M.J. | Fluorescence parameters among leaf photosynthesis-related traits are the best proxies for CO2 assimilation in Central Amazon trees [BibTeX] |
2019 | Brazilian Journal of Botany Vol. 42(2), pp. 239-247 |
article | |
BibTeX:
@article{santos_fluorescence_2019, author = {Santos, Victor Alexandre Hardt Ferreira dos and Nelson, Bruce Walker and Rodrigues, João Victor Figueiredo Cardoso and Garcia, Maquelle Neves and Ceron, João Vitor Barbosa and Ferreira, Marciel José}, title = {Fluorescence parameters among leaf photosynthesis-related traits are the best proxies for CO2 assimilation in Central Amazon trees}, journal = {Brazilian Journal of Botany}, year = {2019}, volume = {42}, number = {2}, pages = {239--247} } |
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Santos, V.A.H.F., Ferreira, M.J., Rodrigues, J.V.F.C., Garcia, M.N., Ceron, J.V.B., Nelson, B.W. and Saleska, S.R. | Causes of reduced leaf‐level photosynthesis during strong El Niño drought in a Central Amazon forest [BibTeX] |
2018 | Global Change Biology, pp. 1-14 | article | DOI |
BibTeX:
@article{santos_causes_2018, author = {Santos, V. A. H. F.dos and Ferreira, M. J. and Rodrigues, J. V. F. C. and Garcia, M. N. and Ceron, J. V. B. and Nelson, B. W. and Saleska, S. R.}, title = {Causes of reduced leaf‐level photosynthesis during strong El Niño drought in a Central Amazon forest}, journal = {Global Change Biology}, year = {2018}, pages = {1--14}, doi = {https://doi.org/10.1111/gcb.14293} } |
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Santos, U.M.d., Goncalves, J.F.D. and Feldpausch, T.R. | Growth, leaf nutrient concentration and photosynthetic nutrient use efficiency in tropical tree species planted in degraded areas in central Amazonia | 2006 | Forest Ecology and Management Vol. 226(1-3), pp. 299-309 |
article | DOI URL |
Abstract: The success of initial tree seedling establishment is related to the capture and use of primary resources such as light and nutrients. The selection of tree species with a greater potential to assimilate carbon and capacity to efficiently utilize nutrients and light would facilitate the revegetation of degraded areas, primarily where irradiance is high and soil nutrient availability low. We analyzed soil physical and chemical characteristics, survival, growth, photosynthesis, chlorophyll a fluorescence, leaf macro- and micro-nutrient content and photosynthetic nutrient use efficiency in young tropical tree species planted in degraded areas in central Amazonia. The species studied were: Bellucia grossularioides, Bombacopsis macrocalyx, Cecropia ficifolia, Cecropia sciadophylla, Chrysophyllum sanguinolentum, Eugenia cumini, Inga edulis and Iryanthera macrophyla. C. sanguinolentum, a late secondary species, exhibited the lowest survival rates, except when compared with B. grossularioides and C sciadophylla. Photosynthesis varied between 34 and 264 nmol g(-1) s(-1) for the eight species; species of Cecropia had photosynthetic values eight times greater than C sanguinolentum. For the photochemical efficiency of photosystem 11, C sanguinolentum presented the highest degree of photoinhibition as a result of an inefficient use of excess irradiance. Leaf macronutrient concentrations varied from 16 to 29, 0.4 to 1.0, 6 to 13, 7 to 22, 1.6 to 3.4 g kg(-1) for N, P, K, Ca and Mg, respectively. For photosynthetic nutrient use efficiency, in general, the two species of Cecropia exhibited the highest values, while C sanguinolentum presented the lowest macronutrient use efficiency. The two species of Cecropia had photosynthetic nitrogen use efficiency seven times greater than C. sanguinolentum. On these highly degraded soils we found that pioneer trees (Cecropia) are better able to colonize than species from other successional stages. Trees on these degraded soils are primarily limited by P or micronutrients. Despite the remove of the 0 horizon, N does not appear to limit photosynthetic activity. From this we conclude that species of Cecropia possess ecophysiological mechanisms associated with carbon assimilation and nutrient use that determines success in early establishment and has potential to recuperate degraded areas, especially when compared to C. sanguinolentum. Early secondary species such as L edulis and E. cumini could also be used with success in forest plantings to recuperate degraded areas when selecting for species, (1) efficient in the utilization of excess energy for photosynthesis, (2) efficient in the use of limited soil nutrients and (3) with high survival and growth rates. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{santos_growth_2006, author = {Santos, U. M. dos and Goncalves, J. F. D. and Feldpausch, T. R.}, title = {Growth, leaf nutrient concentration and photosynthetic nutrient use efficiency in tropical tree species planted in degraded areas in central Amazonia}, journal = {Forest Ecology and Management}, year = {2006}, volume = {226}, number = {1-3}, pages = {299--309}, url = {://WOS:000237138400031}, doi = {https://doi.org/10.1016/j.foreco.2006.01.042} } |
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Santos, S.R.Q., Vitorino, M.I., Harada, A. and Sousa, A.M.L. | Sazonalidade Atmosférica e suas Relações com as Formigas (Hymenoptera, Formicidae) na Flona de Caxiuanã-PA [BibTeX] |
2012 | Revista Brasileira de Meteorologia Vol. 27, pp. 1-10 |
article | |
BibTeX:
@article{santos_sazonalidade_2012, author = {Santos, S. R. Q. and Vitorino, M. I. and Harada, A. and Sousa, A. M. L.}, title = {Sazonalidade Atmosférica e suas Relações com as Formigas (Hymenoptera, Formicidae) na Flona de Caxiuanã-PA}, journal = {Revista Brasileira de Meteorologia}, year = {2012}, volume = {27}, pages = {1--10} } |
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Santos, S.N.M. and Costa, M.H. | A simple tropical ecosystem model of carbon, water and energy fluxes | 2004 | Ecological Modelling Vol. 176(3-4), pp. 291-312 |
article | DOI URL |
Abstract: A simple tropical ecosystem model (SITE) was developed to study the response of tropical ecosystems to environmental conditions. SITE fills the niche of an ecosystem model of intermediate complexity, sophisticated enough to be used to study the fast dynamics of tropical ecosystems, while simple enough to be used to introduce the ecosystem modelling concepts to students and inexperienced modellers. SITE is a dynamic model that incorporates several processes: canopy infrared radiation balance. solar radiation balance, aerodynamic processes, canopy physiology and transpiration, balance of water intercepted by the canopy, transport of mass and energy in the atmosphere, soil heat flux, soil water flux and carbon balance. It is structured with one canopy layer and two soil layers, and is forced by hourly data of temperature, radiation balance, precipitation, humidity and wind, and simulates the fluxes of CO2, water and energy, as well as the dynamics of carbon in the ecosystem. For calibration and validation, we used fluxes of CO2, water vapour and sensible heat, measured at a primary evergreen forest site in Eastern Amazonia. Brazil. Even though SITE is considerably less complex than other models of similar goals, it reproduces well the hourly variability of the fluxes of CO2 and water vapour, and simulates the seasonal scale balance of those elements properly. SITE is available as a 1200-line FORTRAN code, and as a computer spreadsheet. We believe the model will be useful to help train the next generation of tropical ecologists in the use of ecosystem models. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{santos_simple_2004, author = {Santos, S. N. M. and Costa, M. H.}, title = {A simple tropical ecosystem model of carbon, water and energy fluxes}, journal = {Ecological Modelling}, year = {2004}, volume = {176}, number = {3-4}, pages = {291--312}, url = {://WOS:000222558900005}, doi = {https://doi.org/10.1016/j.ecolmodel.2003.10.032} } |
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Santos, C. and S.N.M., M.H. | Simulações de fluxo de carbono em um ecossistema de floresta tropical [BibTeX] |
2003 | Revista Brasileira de Meteorologia Vol. 18, pp. 87-96 |
article | |
BibTeX:
@article{santos_simulacoes_2003, author = {Santos, Costa, M.H., S.N.M.}, title = {Simulações de fluxo de carbono em um ecossistema de floresta tropical}, journal = {Revista Brasileira de Meteorologia}, year = {2003}, volume = {18}, pages = {87--96} } |
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Santos, R., Fisch, G. and Dolman, A. | Erosão da Camada Limite Noturna sobre a Amazônia: aspectos observacionais [BibTeX] |
2003 | Ciência e Natura Vol. v. especial, pp. 291-296 |
article | |
BibTeX:
@article{santos_erosao_2003, author = {Santos, R.M.N.; and Fisch, G. and Dolman, A.J.}, title = {Erosão da Camada Limite Noturna sobre a Amazônia: aspectos observacionais}, journal = {Ciência e Natura}, year = {2003}, volume = {v. especial}, pages = {291--296} } |
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Santos, R.A. and Alves, D.S. | Mudanças Ambientais na Amazônia e as Particularidades da Construção Institucional [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 221-240 |
incollection | |
BibTeX:
@incollection{batistella_mudancas_2008, author = {Santos, Roberto Araújo and Alves, Diógenes S.}, title = {Mudanças Ambientais na Amazônia e as Particularidades da Construção Institucional}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {221--240}, note = {Section: 3} } |
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Santos, L.d. and Fisch, G. | Intercomparação entre quatro métodos de estimativa da altura da camada limite convectiva durante o experimento RACCI – LBA (2002) em Rondônia - Amazônia [BibTeX] |
2007 | Revista Brasileira de Meteorologia Vol. 22(3), pp. 322-328 |
article | |
BibTeX:
@article{santos_intercomparacao_2007, author = {Santos, L.A.R. dos and Fisch, G.}, title = {Intercomparação entre quatro métodos de estimativa da altura da camada limite convectiva durante o experimento RACCI – LBA (2002) em Rondônia - Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2007}, volume = {22}, number = {3}, pages = {322--328} } |
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Santos, M., Aquino, R., Bergamin, A., Silva, D., Marques JR, J., Franca A.B.C., L. and Campos | Caracterização de terras pretas arqueológicas no sul do estado do Amazonas [BibTeX] |
2013 | Revista Brasileira de Ciência do Solo Vol. 37, pp. 825-836 |
article | |
BibTeX:
@article{santos_caracterizacao_2013, author = {Santos, M.C.C.; Aquino, R.E.; Bergamin, A.C.; Silva, D.M.P.; Marques JR, J.; Franca, A.B.C., L.A.C.; Campos}, title = {Caracterização de terras pretas arqueológicas no sul do estado do Amazonas}, journal = {Revista Brasileira de Ciência do Solo}, year = {2013}, volume = {37}, pages = {825--836} } |
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Santos Junior, M.A.d., Alencastro, P.M.L.d., Graça, T.E., Marciente, R., Bobrowiec, P.E.D., Venticinque, E.M., Antunes, A.P., Bastos, A.N., Arasato, L.S. and Rohe, S.A.e.F. | Relações biodiversidade vs. clima em larga escala: importância relativa do clima atual para distribuição potencial de espécies na Amazônia [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 31-42 |
incollection | |
BibTeX:
@incollection{emilio_relacoes_2014-1, author = {Santos Junior, Marcelo Augusto dos and Alencastro, Paulo Maurício Lima de and Graça, Thaise Emilio and Marciente, Rodrigo and Bobrowiec, Paulo Estefano Dineli and Venticinque, Eduardo Martins and Antunes, André Pinassi and Bastos, Anderson Nakanishi and Arasato, Luciana Satiko and Rohe, Silvana Amaral e Fabio}, title = {Relações biodiversidade vs. clima em larga escala: importância relativa do clima atual para distribuição potencial de espécies na Amazônia}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {31--42}, note = {Section: 3} } |
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Santos, J.R., Lacruz, M.S.P., Araujo, L.S. and Keil, M. | Savanna and tropical rainforest biomass estimation and spatialization using JERS-1 data | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1217-1229 |
article | DOI URL |
Abstract: The objective of this study is to show the relation among backscatter signals of JERS-1 images and biophysical parameters (biomass values) of forest and savanna formations. Two contact zones involving these vegetation units in Brazilian Amazonia (Roraima and Mato Grosso States) were selected. A regression model was applied during the analysis of these two variables, based on the best fit function and taking into account the data dispersion. Maps were generated showing biomass spatialization of the vegetation typology found in the study areas. The importance of this study is the innovation referring to the joint analysis of JERS-1 data of these two contact zones in Amazonia, representing both an abrupt contact and a smooth contact along a transition zone of savanna/tropical rainforests formations. | |||||
BibTeX:
@article{santos_savanna_2002, author = {Santos, J. R. and Lacruz, M. S. P. and Araujo, L. S. and Keil, M.}, title = {Savanna and tropical rainforest biomass estimation and spatialization using JERS-1 data}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1217--1229}, url = {://WOS:000174661900002}, doi = {https://doi.org/10.1080/01431160110092867} } |
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Santos, J.R., Freitas, C.C., Araujo, L.S., Dutra, L.V., Mura, J.C., Gama, F.F., Soler, L.S. and Sant'Anna, S.J.S. | Airborne P-band SAR applied to the aboveground biomass studies in the Brazilian tropical rainforest | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 482-493 |
article | DOI URL |
Abstract: The objective of this study is to evaluate the relationship between the response (sigmadegrees) of airborne P-band Synthetic Aperture Radar (SAR) polarimetric data versus biomass values of primary forest and secondary succession. To ensure that different landscapes of "Terra firme" tropical forest of the Brazilian Amazon were represented, a test-site was selected in the lower Tapajos river region (Para State). The microwave signals from the P-band polarimetric images were related to the aboveground biomass data by statistical regression models (logarithmic and polynomial functions). In the field survey, physiognomic and structural aspects of primary forest and regrowth were collected and afterwards the biomass was estimated using allometric equations based on dendrometric, parameters. As an example of the potential use of P-band polarimetric images, they were classified by a contextual classifier (ICM), whose thematic stratification of land use/land cover was associated with biomass class intervals for mapping purposes. The main objective of this P-band experiment is to improve this tool for regional mapping of Amazon landscape changes, due to the growing rate of land use occupation. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{santos_airborne_2003, author = {Santos, J. R. and Freitas, C. C. and Araujo, L. S. and Dutra, L. V. and Mura, J. C. and Gama, F. F. and Soler, L. S. and Sant'Anna, S. J. S.}, title = {Airborne P-band SAR applied to the aboveground biomass studies in the Brazilian tropical rainforest}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {482--493}, url = {://WOS:000186827400008}, doi = {https://doi.org/10.1016/j.rse.2002.12.001} } |
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Santos, E.M.R., Franklin, E. and Luizao, F.J. | Litter manipulation and associated invertebrate fauna in secondary forest, central Amazonia, Brazil | 2008 | Acta Oecologica-International Journal of Ecology Vol. 34(3), pp. 274-284 |
article | DOI URL |
Abstract: Plant litter from selected tree species has been used for improving soil productivity in low-input systems of secondary vegetation in Central Amazon, leading to different conditions for invertebrates. Soil invertebrate assemblages were monitored to test the effects of adding litter types of contrasting nutritional quality and periods of exposure on the development of the community. We established four second growth plots with 80 subplots of 3 m(2) from which the original litter was removed and replaced in 60 subplots. Twenty subplots received Hevea brasiliensis leaves, 20 others Carapa guianensis leaves, and another 20 an equal mixture of H. brasiliensis, C. guianensis and Vismia guianensis. Twenty subplots were left with the original litter. Litter and mineral soil (5 cm deep) sub-horizons were collected after 45, 100, 160, 240 and 300 days of exposure. The invertebrates were extracted using Kempson apparatus. At the day 210, the litter was replenished to match the surrounding litter. Regression analyses showed no significant effect of litter type, but the period of exposure did affect the community in both sub-horizons. Only after the litter replenishment, the type of litter and periods of exposure affected the community in the litter sub-horizon. Because we tried to isolate the effects of litter composition from other large-scale phenomena, several factors interfered in the experiment and potential problems were identified to optimize the investigation. The sampling design must be improved by using a larger number of subsamples for each kind of litter within each plot. Coarse parameters of order and Family were suited to detect major environmental patterns on soil invertebrates, but taxonomic resolution to species and/or morphospecies is required to detect more subtle effects. Future manipulations should also be done on a longer time scale, and the replicates need to be spread over larger areas to capture the natural variations within the ecosystems. (C) 2008 Elsevier Masson SAS. All rights reserved. | |||||
BibTeX:
@article{santos_litter_2008, author = {Santos, Evanira M. R. and Franklin, Elizabeth and Luizao, Flavio J.}, title = {Litter manipulation and associated invertebrate fauna in secondary forest, central Amazonia, Brazil}, journal = {Acta Oecologica-International Journal of Ecology}, year = {2008}, volume = {34}, number = {3}, pages = {274--284}, url = {://WOS:000261502600003}, doi = {https://doi.org/10.1016/j.actao.2008.05.011} } |
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Santos e Silva, C.M., Gielow, R. and de Freitas, S.R. | Diurnal and semidiurnal rainfall cycles during the rain season in SW Amazonia, observed via rain gauges and estimated using S-band radar | 2009 | Atmospheric Science Letters Vol. 10(2), pp. 87-93 |
article | DOI URL |
Abstract: The rainfall field estimated by an S-band radar was evaluated with rain gauges network measurements during the Tropical Rainfall Measuring Mission and Large-Scale Biosphere-Atmosphere Experiment in Amazonia (TRMM-LBA), then the daily variability associated with the presence (absence) of the South Atlantic convergence zone (SACZ) were studied. The results showed the high spatial variability of the rainfall over southwest (SW) Amazonia and suggest that local mechanisms (topography and/or local circulations induced by contrast of vegetation) may be associated with heavy rainfall episodes; moreover, it was possible to observe the squall line influence on the diurnal and semidiurnal cycles. Copyright (C) 2009 Royal Meteorological Society | |||||
BibTeX:
@article{santos_e_silva_diurnal_2009, author = {Santos e Silva, Claudio Moises and Gielow, Ralf and de Freitas, Saulo Ribeiro}, title = {Diurnal and semidiurnal rainfall cycles during the rain season in SW Amazonia, observed via rain gauges and estimated using S-band radar}, journal = {Atmospheric Science Letters}, year = {2009}, volume = {10}, number = {2}, pages = {87--93}, url = {://WOS:000267202000004}, doi = {https://doi.org/10.1002/asl.214} } |
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Santos e SIlva, C., Freitas, S. and Gielow, R. | Numerical simulation of the diurnal cycle of rainfall in SW Amazon basin during the 1999 rainy season: the role of convective trigger function [BibTeX] |
2012 | Theoretical and Applied Climatology Vol. 109, pp. 473-483 |
article | DOI |
BibTeX:
@article{santos_e_silva_numerical_2012, author = {Santos e SIlva, C.M. and Freitas, S. and Gielow, R.}, title = {Numerical simulation of the diurnal cycle of rainfall in SW Amazon basin during the 1999 rainy season: the role of convective trigger function}, journal = {Theoretical and Applied Climatology}, year = {2012}, volume = {109}, pages = {473--483}, doi = {https://doi.org/10.1007/s00704-011-0571-0} } |
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Santos e Silva, C.M., de Freitas, S.R., Gielow, R. and de Barros, S.S. | Evaluation of high-resolution precipitation estimate over the Amazon Basin | 2009 | Atmospheric Science Letters Vol. 10(4), pp. 273-278 |
article | DOI URL |
Abstract: Using rainfall data from S-band radar measurements, the estimative of the rainfall from the 3B42_V6 algorithm was evaluated for the region of the Tropical Rainfall Measurement Mission and Large Scale Biosphere-Atmosphere Experiment in Amazonia (TRMM-LBA) experiment, which was conducted in the Amazon Basin during the 1999 rainy season. The algorithm correctly represented the diurnal rainfall cycle, but underestimated overall precipitation rates by about 50%. It adequately represented most of the stratiform (convective) rainfall during the break (active) phase of the South American Monsoon System (SAMS). Thus, some uncertainties, as well as the algorithm applicability for the region and period studied, were demonstrated. Copyright. (C) 2009 Royal Meteorological Society | |||||
BibTeX:
@article{santos_e_silva_evaluation_2009, author = {Santos e Silva, Claudio Moises and de Freitas, Saulo Ribeiro and Gielow, Ralf and de Barros, Sheila Santana}, title = {Evaluation of high-resolution precipitation estimate over the Amazon Basin}, journal = {Atmospheric Science Letters}, year = {2009}, volume = {10}, number = {4}, pages = {273--278}, url = {://WOS:000272961600010}, doi = {https://doi.org/10.1002/asl.242} } |
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Santos, D.M.d., Oliveira, P., Manzi, A.A., Demarco, G. and Acevedo, O.C. | Quantificação da intermitência na camada limite estável em um sítio experimental na floresta amazônica [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 222 - 224 |
article | |
BibTeX:
@article{santos_quantificacao_2013, author = {Santos, Daniel M. dos and Oliveira, Pablo and Manzi, Antônio A. and Demarco, Giuliano and Acevedo, Otávio C.}, title = {Quantificação da intermitência na camada limite estável em um sítio experimental na floresta amazônica}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {222 -- 224} } |
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Santos, D.M., Acevedo, O.C., Chamecki, M., Fuentes, J.D., Gerken, T. and Stoy, P.C. | Temporal Scales of the Nocturnal Flow Within and Above a Forest Canopy in Amazonia [BibTeX] |
2016 | Boundary-Layer Meteorology | article | DOI |
BibTeX:
@article{santos_temporal_2016, author = {Santos, Daniel M. and Acevedo, Otávio C. and Chamecki, Marcelo and Fuentes, José D. and Gerken, T. and Stoy, Paul C.}, title = {Temporal Scales of the Nocturnal Flow Within and Above a Forest Canopy in Amazonia}, journal = {Boundary-Layer Meteorology}, year = {2016}, doi = {https://doi.org/10.1007/s10546-016-0158-5} } |
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Santos, P., Santos E.M., C. and Satyamurty | Tendências de índices de extremos climáticos para a região de Manaus-AM [BibTeX] |
2012 | Acta Amazonica Vol. 42, pp. 329-336 |
article | |
BibTeX:
@article{santos_tendencias_2012, author = {Santos, P.; Santos, E.M., C.A.C.; Satyamurty}, title = {Tendências de índices de extremos climáticos para a região de Manaus-AM}, journal = {Acta Amazonica}, year = {2012}, volume = {42}, pages = {329--336} } |
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Santos Silva, B.R.T.S.P.M.A.C. | Downward longwave radiation estimates for clear-sky conditions over Northeast Brazil [BibTeX] |
2011 | Revista Brasileira de Meteorologia Vol. 26(3), pp. 287 - 294 |
article | |
BibTeX:
@article{santos_downward_2011, author = {Santos, Silva, B.B., Rao, T.V.R., Satyamurty, P., Manzi. A.O., C.A.C.}, title = {Downward longwave radiation estimates for clear-sky conditions over Northeast Brazil}, journal = {Revista Brasileira de Meteorologia}, year = {2011}, volume = {26}, number = {3}, pages = {287 -- 294} } |
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Santos, A.J.d., Campos, J.G., Acevedo, O.C., Sá, M.d.O. and Manzi, A.O. | Comparação dos fluxos noturnos de CO2 e calor sensível em Manaus e São Gabriel da Cachoeira [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 87-90 |
article | |
BibTeX:
@article{santos_comparacao_2007, author = {Santos, Alexandre J.B. dos and Campos, José G. and Acevedo, Otávio C. and Sá, Marta de O. and Manzi, Antônio O.}, title = {Comparação dos fluxos noturnos de CO2 e calor sensível em Manaus e São Gabriel da Cachoeira}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {87--90} } |
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Santos, A.J.B., Silva, G., Miranda, H.S., Miranda, A.C. and Lloyd, J. | Effects of fire on surface carbon, energy and water vapour fluxes over campo sujo savanna in central Brazil | 2003 | Functional Ecology Vol. 17(6), pp. 711-719 |
article | DOI URL |
Abstract: 1. Tower-based eddy covariance measurements were used to quantify the effect of fire on subsequent carbon dioxide fluxes and water and surface energy balance characteristics for campo sujo savanna located near Brasilia in Central Brazil (15degrees56' S, 47degrees51' W). Campo sujo is a xeromorphic, open shrub savanna with very scattered but definitely visible shrubs and tree-like shrub elements. We studied two areas, one exposed to a prescribed fire late in the dry season, and a second that had not been burned for the previous 4 years. 2. The fire on 22 September 1998 consumed an estimated 26 mol C m(-2). Immediately after the fire, evapotranspiration rates decreased and the savanna became a stronger net source of CO(2) to the atmosphere. This was attributed to the removal of the still slightly physiologically active grass layer and higher soil CO(2) efflux rates as a consequence of elevated surface soil temperatures post-burning. 3. On the commencement of the first rains in early October 1998, this situation was reversed, with the burned area rapidly becoming a stronger sink for CO(2) and with higher evapotranspiration rates than a nearby unburned (control) area. This difference persisted throughout the wet season (until at least June 1999) and was attributable to greater physiological activity of the regrowing vegetation in the burned area. Early in the growing season, higher soil evaporation rates may also have contributed to faster water use by the previously burned area. 4. Overall, we estimate an annual gross primary productivity for the burned area of 135 mol C m(-2) year(-1), with that for the unburned area being 106 mol C m(-2) year(-1). Estimated ecosystem respiration rates were more similar on an annual basis (96 and 82 mol C m(-2) year(-1) for the burned and unburned areas, respectively), giving rise to a substantially higher net ecosystem productivity for the previously burned area (38 vs 24 mol C m(-2) year(-1)). 5. Stimulation of photosynthetic activity in the rapid post-fire growth phase means that the negative effects of fire on the ecosystem carbon balance were more or less neutralized after only 12 months. | |||||
BibTeX:
@article{santos_effects_2003, author = {Santos, A. J. B. and Silva, Gtda and Miranda, H. S. and Miranda, A. C. and Lloyd, J.}, title = {Effects of fire on surface carbon, energy and water vapour fluxes over campo sujo savanna in central Brazil}, journal = {Functional Ecology}, year = {2003}, volume = {17}, number = {6}, pages = {711--719}, url = {://WOS:000187184900001}, doi = {https://doi.org/10.1111/j.1365-2435.2003.00790.x} } |
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Santos, A.J.B., Quesada, C.A., Da Silva, G.T., Maia, J.F., Miranda, H.S., Miranda, A.C. and Lloyd, J. | High rates of net ecosystem carbon assimilation by Brachiara pasture in the Brazilian Cerrado | 2004 | Global Change Biology Vol. 10(5), pp. 877-885 |
article | DOI URL |
Abstract: To investigate the consequences of land use on carbon and energy exchanges between the ecosystem and atmosphere, we measured CO2 and water vapour fluxes over an introduced Brachiara brizantha pasture located in the Cerrado region of Central Brazil. Measurements using eddy covariance technique were carried out in field campaigns during the wet and dry seasons. Midday CO2 net ecosystem exchange rates during the wet season were -40 mumol m(-2) s(-1), which is more than twice the rate found in the dry season (-15 mumol m(-2) s(-1)). This was observed despite similar magnitudes of irradiance, air and soil temperatures. During the wet season, inferred rates of canopy photosynthesis did not show any tendency to saturate at high solar radiation levels, with rates of around 50 mumol m(-2) s(-1) being observed at the maximum incoming photon flux densities of 2200 mumol m(-2) s(-1). This contrasted strongly to the dry period when light saturation occurred with 1500 mumol m(-2) s(-1) and with maximum canopy photosynthetic rates of only 20 mumol m(-2) s(-1). Both canopy photosynthetic rates and night-time ecosystem CO2 efflux rates were much greater than has been observed for cerrado native vegetation in both the wet and dry seasons. Indeed, observed CO2 exchange rates were also much greater than has previously been reported for C-4 pastures in the tropics. The high rates in the wet season may have been attributable, at least in part, to the pasture not being grazed. Higher than expected net rates of carbon acquisition during the dry season may also have been attributable to some early rain events. Nevertheless, the present study demonstrates that well-managed, productive tropical pastures can attain ecosystem gas exchange rates equivalent to fertilized C-4 crops growing in the temperate zone. | |||||
BibTeX:
@article{santos_high_2004, author = {Santos, A. J. B. and Quesada, C. A. and Da Silva, G. T. and Maia, J. F. and Miranda, H. S. and Miranda, A. C. and Lloyd, J.}, title = {High rates of net ecosystem carbon assimilation by Brachiara pasture in the Brazilian Cerrado}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {877--885}, url = {://WOS:000221421600024}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00777.x} } |
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Santos, A., Costa, A., Oliveira, J. and Filho, M. | Estudo de caso da variabilidade de parâmetros microfísicos em nuvens da Amazonia [BibTeX] |
2002 | Revista Brasileira de Meteorologia Vol. 17(2), pp. 141- 151 |
article | |
BibTeX:
@article{santos_estudo_2002, author = {Santos, A.C.S. and Costa, A.A. and Oliveira, J.C.P. and Filho, M.C.C.}, title = {Estudo de caso da variabilidade de parâmetros microfísicos em nuvens da Amazonia}, journal = {Revista Brasileira de Meteorologia}, year = {2002}, volume = {17}, number = {2}, pages = {141-- 151} } |
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Santana, R.F. | Os serviços ambientais da floresta e o manejo florestal sustentável: perspectivas para os agricultores familiares na área de influência da BR-163. [BibTeX] |
2008 | Vol. 1Sociedade, Território e Conflitos: BR-163 em questão, pp. 147-188 |
incollection | |
BibTeX:
@incollection{castro_os_2008, author = {Santana, R. F.}, title = {Os serviços ambientais da floresta e o manejo florestal sustentável: perspectivas para os agricultores familiares na área de influência da BR-163.}, booktitle = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, pages = {147--188} } |
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Santana, R.S.d., Tota, J., Santos, R.M.N.d., Fitzjarrald, D.R., Picanco, G.A.S., Batalha, S.S.A., Gomes, A.C.S., Tapajos, R., Silva R. ., R.A.S. and Vale | Características Médias do vento acima e abaixo do dossel da floresta durante o GOAMAZON em um sítio experimental na Amazônia [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 152 |
article | |
BibTeX:
@article{santana_caracteristicas_2016, author = {Santana, Roseilson Souza do ; Tota, J. ; Santos, Rosa Maria Nascimento dos ; Fitzjarrald, D. R. ; Picanco, G. A. S. ; Batalha, S. S. A. ; Gomes, A. C. S. ; Tapajos, R. ; Silva, R. ., R. A. S. ; Vale}, title = {Características Médias do vento acima e abaixo do dossel da floresta durante o GOAMAZON em um sítio experimental na Amazônia}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {152} } |
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Santana, R.A.S.d., Dias-Júnior, C.Q., Vale, R.S.d., Tóta, J. and Fitzjarrald, D.R. | Observing and Modeling the Vertical Wind Profile at Multiple Sites in and above the Amazon Rain Forest Canopy [BibTeX] |
2017 | Advances in Meteorology, pp. p. 1-8 | article | |
BibTeX:
@article{santana_observing_2017, author = {Santana, Raoni Aquino Silva de and Dias-Júnior, Cléo Quaresma and Vale, Roseilson Souza do and Tóta, Júlio and Fitzjarrald, David Roy}, title = {Observing and Modeling the Vertical Wind Profile at Multiple Sites in and above the Amazon Rain Forest Canopy}, journal = {Advances in Meteorology}, year = {2017}, pages = {p. 1--8} } |
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Santana, R.A., Dias-Júnior, C.Q., Silva, J.T.d., Fuentes, J.D., Vale, R.S., Alves, E.G., Santos, R.M.N. and Manzi, A.O. | Air turbulence characteristics at multiple sites in and above the Amazon rainforest canopy [BibTeX] |
2018 | Agricultural and Forest Meteorology Vol. 260–261, pp. 41-54 |
article | |
BibTeX:
@article{santana_air_2018, author = {Santana, Raoni A. and Dias-Júnior, Cléo Q. and Silva, Júlio Tóta da and Fuentes, Jose D. and Vale, Roseilson Souzado and Alves, Eliane Gomes and Santos, Rosa Maria N.dos and Manzi, Antônio O.}, title = {Air turbulence characteristics at multiple sites in and above the Amazon rainforest canopy}, journal = {Agricultural and Forest Meteorology}, year = {2018}, volume = {260–261}, pages = {41--54} } |
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Santana, R., Tota, J., Santos, R.M.d. and Vale, R.d. | Jatos de Baixos Níveis no sudeste da Amazônia [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 410 - 413 |
article | |
BibTeX:
@article{santana_jatos_2013, author = {Santana, Raoni and Tota, Júlio and Santos, Rosa Maria dos and Vale, Roseilson do}, title = {Jatos de Baixos Níveis no sudeste da Amazônia}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {410 -- 413} } |
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Sano, E.E., Ferreira, L.G. and Huete, A.R. | Synthetic aperture radar (L band) and optical vegetation indices for discriminating the Brazilian savanna physiognomies: A comparative analysis | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: The all-weather capability, signal independence to the solar illumination angle, and response to 3D vegetation structures are the highlights of active radar systems for natural vegetation mapping and monitoring. However, they may present significant soil background effects. This study addresses a comparative analysis of the performance of L-band synthetic aperture radar (SAR) data and optical vegetation indices (VIs) for discriminating the Brazilian cerrado physiognomies. The study area was the Brasilia National Park, Brazil, one of the test sites of the Large-Scale Biosphere - Atmosphere (LBA) experiment in Amazonia. Seasonal Japanese Earth Resources Satellite-1 (JERS-1) SAR backscatter coefficients (sigma(o)) were compared with two vegetation indices [ normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI)] over the five most dominant cerrados' physiognomies plus gallery forest. In contrast to the VIs, sigma(o) from dry and wet seasons did not change significantly, indicating primary response to vegetation structures. Discriminant analysis and analysis of variance ( ANOVA) showed an overall higher performance of radar data. However, when both SAR and VIs are combined, the discrimination capability increased significantly, indicating that the fusion of the optical and radar backscatter observations provides overall improved classifications of the cerrado types. In addition, VIs showed good performance for monitoring the cerrado dynamics. | |||||
BibTeX:
@article{sano_synthetic_2005, author = {Sano, Edson E. and Ferreira, Laerte G. and Huete, Alfredo R.}, title = {Synthetic aperture radar (L band) and optical vegetation indices for discriminating the Brazilian savanna physiognomies: A comparative analysis}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241214200001} } |
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Sano, E.E., Ferreira, L.G., Asner, G.P. and Steinke, E.T. | Spatial and temporal probabilities of obtaining cloud-free Landsat images over the Brazilian tropical savanna | 2007 | International Journal of Remote Sensing Vol. 28(12), pp. 2739-2752 |
article | DOI URL |
Abstract: Remotely sensed data are the best and perhaps the only possible way for monitoring large-scale, human-induced land occupation and biosphere-atmosphere processes in regions such as the Brazilian tropical savanna (Cerrado). Landsat imagery has been intensively employed for these studies because of their long-term data coverage (textgreater 30 years), suitable spatial and temporal resolutions, and ability to discriminate different land-use and land-cover classes. However, cloud cover is the most obvious constraint for obtaining optical remote sensing data in tropical regions, and cloud cover analysis of remotely sensed data is a requisite step needed for any optical remote sensing studies. This study addresses the extent to which cloudiness can restrict the monitoring of the Brazilian Cerrado from Landsat-like sensors. Percent cloud cover from more than 35 500 Landsat quick-looks were estimated by the K-means unsupervised classification technique. The data were examined by month, season, and El Nino Southern Oscillation event. Monthly observations of any part of the biome are highly unlikely during the wet season (October-March), but very possible during the dry season, especially in July and August. Research involving seasonality is feasible in some parts of the Cerrado at the temporal satellite sampling frequency of Landsat sensors. There are several limitations at the northern limit of the Cerrado, especially in the transitional area with the Amazon. During the 1997 El Nino event, the cloudiness over the Cerrado decreased to a measurable but small degree (5% less, on average). These results set the framework and limitations of future studies of land use/ land cover and ecological dynamics using Landsat-like satellite sensors. | |||||
BibTeX:
@article{sano_spatial_2007, author = {Sano, E. E. and Ferreira, L. G. and Asner, G. P. and Steinke, E. T.}, title = {Spatial and temporal probabilities of obtaining cloud-free Landsat images over the Brazilian tropical savanna}, journal = {International Journal of Remote Sensing}, year = {2007}, volume = {28}, number = {12}, pages = {2739--2752}, url = {://WOS:000246903500007}, doi = {https://doi.org/10.1080/01431160600981517} } |
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Sanches, L., Reis de Andrade, N.L., Costa, M.H., Alves, M.d.C. and Gaio, D. | Performance evaluation of the SITEA (R) model to estimate energy flux in a tropical semi-deciduous forest of the southern Amazon Basin | 2011 | International Journal of Biometeorology Vol. 55(3), pp. 303-312 |
article | DOI URL |
Abstract: The SITEA (R) model was originally developed to study the response of tropical ecosystems to varying environmental conditions. The present study evaluated the applicability of the SITE model to simulation of energy fluxes in a tropical semi-deciduous forest of the southern Amazon Basin. The model was simulated with data representing the wet and dry season, and was calibrated according to each season. The output data of the calibrated model [net radiation (Rn), latent heat flux (LE) and sensible heat flux (H)] were compared with data observed in the field for validation. Considering changes in parameter calibration for a time step simulation of 30 min, the magnitude of variation in temporal flux was satisfactory when compared to observation field data. There was a tendency to underestimate and overestimate LE and H, respectively. Of all the calibration parameters, the soil moisture parameter presented the highest variation over the seasons, thus influencing SITE model performance. | |||||
BibTeX:
@article{sanches_performance_2011, author = {Sanches, Luciana and Reis de Andrade, Nara Lusa and Costa, Marcos Heil and Alves, Marcelo de Carvalho and Gaio, Denilton}, title = {Performance evaluation of the SITEA (R) model to estimate energy flux in a tropical semi-deciduous forest of the southern Amazon Basin}, journal = {International Journal of Biometeorology}, year = {2011}, volume = {55}, number = {3}, pages = {303--312}, note = {Edition: 2010/07/01}, url = {://WOS:000289561600003}, doi = {https://doi.org/10.1007/s00484-010-0337-x} } |
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Sanches, L., Abido Valentini, C.M., Pinto Junior, O.B., Nogueira, J.d.S., Vourlitis, G.L., Biudes, M.S., da Silva, C.J., Bambi, P. and Lobo, F.d.A. | Seasonal and interannual litter dynamics of a tropical semideciduous forest of the southern Amazon Basin, Brazil | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113(G4) |
article | DOI URL |
Abstract: This study analyzed how seasonal and interannual variations in climate alter litter dynamics, including production, decomposition, and accumulation. Monthly measurements of leaf, stem, and reproductive ( flower plus fruit) litter and the forest floor litter mass were combined with a mass balance model to determine rates of litter decomposition for a semideciduous tropical forest located in the rain forest-savanna ecotone of the southern Amazon Basin for 2001-2007. Annual rates of litter production varied between 8 and 10.5 Mg ha(-1) a(-1), and leaf litter production accounted for the majority (similar to 70%) of the total litter production. Leaf litter production peaked at the end of the May - August dry season while stem litter production peaked during the wet season and reproductive litter production peaked during the dry-wet season transition. Forest floor litter mass ranged between 5 and 8 Mg ha(-1) over the study period and generally declined as litter inputs declined. Litter decomposition rates were remarkably stable from year-to-year and varied between 10.8 and 12.4 Mg ha(-1) a(-1). On average, rates of litter decomposition were highest during the dry-wet season transition. Overall, our results suggest that rainfall variability directly altered litter production dynamics and indirectly altered forest floor litter mass and decomposition kinetics through its effect on litter production. Future changes in seasonal and/or interannual rainfall patterns, whether in response to El Nino or to anthropogenic climate change, will likely have important consequences for the litter dynamics of Amazonian semideciduous forest. | |||||
BibTeX:
@article{sanches_seasonal_2008, author = {Sanches, Luciana and Abido Valentini, Carla Maria and Pinto Junior, Osvaldo Borges and Nogueira, Jose de Souza and Vourlitis, George Louis and Biudes, Marcelo Sacardi and da Silva, Carlos Jose and Bambi, Paulino and Lobo, Francisco de Almeida}, title = {Seasonal and interannual litter dynamics of a tropical semideciduous forest of the southern Amazon Basin, Brazil}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, number = {G4}, url = {://WOS:000260178700001}, doi = {https://doi.org/10.1029/2007jg000593} } |
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Sanches, F. and Fisch, G. | As possíveis alterações microclimáticas devido a formação do lago artificial da hidrelétrica de Tucuruí-PA [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 41-50 |
article | |
BibTeX:
@article{sanches_as_2005, author = {Sanches, F.O. and Fisch, G.}, title = {As possíveis alterações microclimáticas devido a formação do lago artificial da hidrelétrica de Tucuruí-PA}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {41--50} } |
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Sanaiotti, T.M., Martinelli, L.A., Victoria, R.L., Trumbore, S.E. and Camargo, P.B. | Past vegetation changes in Amazon savannas determined using carbon isotopes of soil organic matter | 2002 | Biotropica Vol. 34(1), pp. 2-16 |
article | DOI URL |
Abstract: We investigated the variation of stable (delta(13)C) soil carbon isotopes in relation to depth in seven of the most important savanna are-as to adjacent contiguous forests in the Amazon region. The delta(13)C of bulk organic matter in all profiles from forested sites increased with sod depth. In forest profiles from Amapa, Alter do Chao, and Roraima, the enrichment was less than 3.5parts per thousand between deeper soil and surface layers, suggesting that C-3 plants have remained the dominant vegetation cover. On the other hand, in forest soil profiles from Humaita and Carolina sites, the delta(13)C enrichment was greater than 3.5parts per thousand indicating the influence of past C-4 vegetation or a mixture Of C-3/C-4 vegetation (woody savanna). The surface delta(13)C values in the savanna profiles were 5-13parts per thousand greater than the comparable Forest profiles, indicating the influence of C-4 vegetation. Two kinds of isotopic distribution were observed in deeper layers. The savanna profiles at Alter do Chao, Chapada dos Parecis, and Redencao had relatively constant delta(13)C values throughout the profile, suggesting minor past changes in the vegetation composition, In profiles at Amapa, Roraima, Humaita, and Carolina, delta(13)C values decreased with depth from the surface and converged with comparable forest values, suggesting more woody savanna in the past than exists currently. | |||||
BibTeX:
@article{sanaiotti_past_2002, author = {Sanaiotti, T. M. and Martinelli, L. A. and Victoria, R. L. and Trumbore, S. E. and Camargo, P. B.}, title = {Past vegetation changes in Amazon savannas determined using carbon isotopes of soil organic matter}, journal = {Biotropica}, year = {2002}, volume = {34}, number = {1}, pages = {2--16}, url = {://WOS:000175063600001}, doi = {https://doi.org/10.1111/j.1744-7429.2002.tb00237.x} } |
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Sampaio, G., Shimizu, M.H., Guimarães-Júnior, C.A., Alexandre, F., Guatura, M., Cardoso, M., Domingues, T.F., Rammig, A., von Randow, C., Rezende, L.F.C. and Lapola, D.M. | CO2 physiological effect can cause rainfall decrease as strong as large-scale deforestation in the Amazon [BibTeX] |
2021 | Biogeosciences Vol. 18(8), pp. 2511-2525 |
article | DOI URL |
BibTeX:
@article{sampaio_co2_2021, author = {Sampaio, G. and Shimizu, M. H. and Guimarães-Júnior, C. A. and Alexandre, F. and Guatura, M. and Cardoso, M. and Domingues, T. F. and Rammig, A. and von Randow, C. and Rezende, L. F. C. and Lapola, D. M.}, title = {CO2 physiological effect can cause rainfall decrease as strong as large-scale deforestation in the Amazon}, journal = {Biogeosciences}, year = {2021}, volume = {18}, number = {8}, pages = {2511--2525}, url = {https://bg.copernicus.org/articles/18/2511/2021/}, doi = {https://doi.org/10.5194/bg-18-2511-2021} } |
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Sampaio, G., Nobre, C., Costa, M.H., Satyamurty, P., Soares-Filho, B.S. and Cardoso, M. | Regional climate change over eastern Amazonia caused by pasture and soybean cropland expansion | 2007 | Geophysical Research Letters Vol. 34(17) |
article | DOI URL |
Abstract: Field observations and numerical studies revealed that large scale deforestation in Amazonia could alter the regional climate significantly, projecting a warmer and somewhat drier post-deforestation climate. In this study we employed the CPTEC-INPE AGCM to assess the effects of Amazonian deforestation on the regional climate, using simulated land cover maps from a business-as-usual scenario of future deforestation in which the rainforest was gradually replaced by degraded pasture or by soybean cropland. The results for eastern Amazonia, where changes in land cover are expected to be larger, show increase in near-surface air temperature, and decrease in evapotranspiration and precipitation, which occurs mainly during the dry season. The relationship between precipitation and deforestation shows an accelerating decrease of rainfall for increasing deforestation for both classes of land use conversions. Continued expansion of cropland in Amazonia is possible and may have important consequences for the sustainability of the region's remaining natural vegetation. | |||||
BibTeX:
@article{sampaio_regional_2007, author = {Sampaio, Gilvan and Nobre, Carlos and Costa, Marcos Heil and Satyamurty, Prakki and Soares-Filho, Britaldo Silveira and Cardoso, Manoel}, title = {Regional climate change over eastern Amazonia caused by pasture and soybean cropland expansion}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {17}, url = {://WOS:000249518000005}, doi = {https://doi.org/10.1029/2007gl030612} } |
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Sampaio Filho, I.D.J., Jardine, K.J., De Oliveira, R.C.A., Gimenez, B.O., Cobello, L.O., Piva, L.R.d.O., Candido, L.A., Higuchi, N. and Chambers, J.Q. | Below versus above Ground Plant Sources of Abscisic Acid (ABA) at the Heart of Tropical Forest Response to Warming [BibTeX] |
2018 | International Journal of Molecular Sciences Vol. 19(7), pp. 2023 |
article | URL |
BibTeX:
@article{sampaio_filho_below_2018, author = {Sampaio Filho, Israel De Jesus and Jardine, Kolby Jeremiah and De Oliveira, Rosilena Conceição Azevedo and Gimenez, Bruno Oliva and Cobello, Leticia Oliveira and Piva, Luani Rosa de Oliveira and Candido, Luiz Antonio and Higuchi, Niro and Chambers, Jeffrey Quintin}, title = {Below versus above Ground Plant Sources of Abscisic Acid (ABA) at the Heart of Tropical Forest Response to Warming}, journal = {International Journal of Molecular Sciences}, year = {2018}, volume = {19}, number = {7}, pages = {2023}, url = {https://www.mdpi.com/1422-0067/19/7/2023} } |
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Samanta, A., Costa, M.H., Nunes, E.L., Vieira, S.A., Xu, L. and Myneni, R.B. | Comment on "Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009" | 2011 | Science Vol. 333(6046), pp. 1093; author reply 1093 |
article | DOI URL |
Abstract: Zhao and Running (Reports, 20 August 2010, p. 940) reported a reduction in global terrestrial net primary production (NPP) from 2000 through 2009. We argue that the small trends, regional patterns, and interannual variations that they describe are artifacts of their NPP model. Satellite observations of vegetation activity show no statistically significant changes in more than 85% of the vegetated lands south of 70 degrees N during the same 2000 to 2009 period. | |||||
BibTeX:
@article{samanta_comment_2011, author = {Samanta, Arindam and Costa, Marcos H. and Nunes, Edson L. and Vieira, Simone A. and Xu, Liang and Myneni, Ranga B.}, title = {Comment on "Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009"}, journal = {Science}, year = {2011}, volume = {333}, number = {6046}, pages = {1093; author reply 1093}, note = {Edition: 2011/08/27}, url = {://WOS:000294244300023}, doi = {https://doi.org/10.1126/science.1199048} } |
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Sallo, F.d.S., Sanches, L., Morais Dias, V.R.d., Palácios, R.d.S. and Nogueira, J.d.S. | Stem water storage dynamics of Vochysia divergens in a seasonally flooded environment [BibTeX] |
2017 | Agricultural and Forest Meteorology Vol. 232(15), pp. 566-575 |
article | |
BibTeX:
@article{sallo_stem_2017, author = {Sallo, Fernando da Silva and Sanches, Luciana and Morais Dias, Vanessa Rakel de and Palácios, Rafael da Silva and Nogueira, José de Souza}, title = {Stem water storage dynamics of Vochysia divergens in a seasonally flooded environment}, journal = {Agricultural and Forest Meteorology}, year = {2017}, volume = {232}, number = {15}, pages = {566--575} } |
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Salinas, N., Malhi, Y., Meir, P., Silman, M., Cuesta, R.R., Huaman, J., Salinas, D., Huaman, V., Gibaja, A., Mamani, M. and Farfan, F. | The sensitivity of tropical leaf litter decomposition to temperature: results from a large-scale leaf translocation experiment along an elevation gradient in Peruvian forests | 2011 | New Phytologist Vol. 189(4), pp. 967-977 |
article | DOI URL |
Abstract: We present the results from a litter translocation experiment along a 2800-m elevation gradient in Peruvian tropical forests. The understanding of the environmental factors controlling litter decomposition is important in the description of the carbon and nutrient cycles of tropical ecosystems, and in predicting their response to long-term increases in temperature. Samples of litter from 15 species were transplanted across all five sites in the study, and decomposition was tracked over 448 d. Species' type had a large influence on the decomposition rate (k), most probably through its influence on leaf quality and morphology. When samples were pooled across species and elevations, soil temperature explained 95% of the variation in the decomposition rate, but no direct relationship was observed with either soil moisture or rainfall. The sensitivity of the decay rate to temperature (kappa(T)) varied seven-fold across species, between 0.024 and 0.169 degrees C(-1), with a mean value of 0.118 +/- 0.009 degrees C(-1) (SE). This is equivalent to a temperature sensitivity parameter (Q(10)) for litter decay of 3.06 +/- 0.28, higher than that frequently assumed for heterotrophic processes. Our results suggest that the warming of approx. 0.9 degrees C experienced in the region in recent decades may have increased decomposition and nutrient mineralization rates by c. 10%. | |||||
BibTeX:
@article{salinas_sensitivity_2011, author = {Salinas, N. and Malhi, Y. and Meir, P. and Silman, M. and Cuesta, R. Roman and Huaman, J. and Salinas, D. and Huaman, V. and Gibaja, A. and Mamani, M. and Farfan, F.}, title = {The sensitivity of tropical leaf litter decomposition to temperature: results from a large-scale leaf translocation experiment along an elevation gradient in Peruvian forests}, journal = {New Phytologist}, year = {2011}, volume = {189}, number = {4}, pages = {967--977}, note = {Edition: 2010/11/17}, url = {://WOS:000286940500010}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03521.x} } |
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Salimon, C. and Santos Sousa, E. | Alto Purus: influência da sazonalidade na biogeoquímica e nos fluxos de Carbono [BibTeX] |
2012 | Rio Purus: águas, território e sociedade na Amazônia Sul-Ocidental | incollection | |
BibTeX:
@incollection{librimundi_alto_2012, author = {Salimon, C.I. and Santos Sousa, E.}, title = {Alto Purus: influência da sazonalidade na biogeoquímica e nos fluxos de Carbono}, booktitle = {Rio Purus: águas, território e sociedade na Amazônia Sul-Ocidental}, publisher = {Sousa Junior, Wilson Cabral de Waichman, Andréa Viviana Sinisgalli, Paulo Antônio de Almeida Angelis, Carlos Frederico de Romeiro, Ademar Ribeiro}, year = {2012} } |
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Salimon, C.I., Putz, F.E., Menezes-Filho, L., Anderson, A., Silveira, M., Brown, I.F. and Oliveira, L.C. | Estimating state-wide biomass carbon stocks for a REDD plan in Acre, Brazil | 2011 | Forest Ecology and Management Vol. 262(3), pp. 555-560 |
article | DOI URL |
Abstract: As in many other developing countries, the state government of Acre, Brazil, is developing a program for compensating forest holders (such as communities of rubber tappers and indigenous peoples as well as small, medium and large private land holders) reducing their emission of atmospheric heat-trapping gases by not deforesting. We describe and then apply to Acre a method for estimating carbon stocks by land cover type. We then compare the results of our simple method, which is based on vegetation mapping and ground-based samples, with other more technically demanding methods based on remote sensing. We estimated total biomass carbon stocks by multiplying the measured above-ground biomass of trees textgreater10 cm DBH in each of 18 forest types and published estimates for non-forest areas, as determined by measurement of 44 plots throughout the state (ranging from 1 to 10 ha each), by land-cover area estimated using a geographical information system. State-wide, we estimated average above-ground biomass in forested areas to be 246 +/- 90 Mg ha(-1); dense forest showed highest (322 +/- 20 Mg ha(-1)) and oligotrophic dwarf forest (campinarana) the lowest biomass (20 +/- 30 Mg ha(-1)). The two most widespread forest types in Acre, open canopy forests dominated by either palms and bamboo (for which ground-based data are scant), support an estimated 246 +/- 44 and 224 +/- 50 Mg ha(-1) of above-ground biomass, respectively. We calculate the total above-ground biomass of the 163,000 km(2) State of Acre to be 3.6 +/- 0.8 Pg (non-forest biomass included). This estimate is very similar to two others generated using much more technologically demanding methods, but all three methods, regardless of sophistication, suffer from lack of field data. | |||||
BibTeX:
@article{salimon_estimating_2011, author = {Salimon, Cleber I. and Putz, Francis E. and Menezes-Filho, L. and Anderson, Anthony and Silveira, Marcos and Brown, I. Foster and Oliveira, L. C.}, title = {Estimating state-wide biomass carbon stocks for a REDD plan in Acre, Brazil}, journal = {Forest Ecology and Management}, year = {2011}, volume = {262}, number = {3}, pages = {555--560}, url = {://WOS:000292428500028}, doi = {https://doi.org/10.1016/j.foreco.2011.04.025} } |
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Salimon, C.I., Davidson, E.A., Victoria, R.L. and Melo, A.W.F. | CO2 flux from soil in pastures and forests in southwestern Amazonia | 2004 | Global Change Biology Vol. 10(5), pp. 833-843 |
article | DOI URL |
Abstract: Stocks of carbon in Amazonian forest biomass and soils have received considerable research attention because of their potential as sources and sinks of atmospheric CO2. Fluxes of CO2 from soil to the atmosphere, on the other hand, have not been addressed comprehensively in regard to temporal and spatial variations and to land cover change, and have been measured directly only in a few locations in Amazonia. Considerable variation exists across the Amazon Basin in soil properties, climate, and management practices in forests and cattle pastures that might affect soil CO2 fluxes. Here we report soil CO2 fluxes from an area of rapid deforestation in the southwestern Amazonian state of Acre. Specifically we addressed (1) the seasonal variation of soil CO2 fluxes, soil moisture, and soil temperature; (2) the effects of land cover (pastures, mature, and secondary forests) on these fluxes; (3) annual estimates of soil respiration; and (4) the relative contributions of grass-derived and forest-derived C as indicated by delta(13)CO(2). Fluxes were greatest during the wet season and declined during the dry season in all land covers. Soil respiration was significantly correlated with soil water-filled pore space but not correlated with temperature. Annual fluxes were higher in pastures compared with mature and secondary forests, and some of the pastures also had higher soil C stocks. The delta(13)C of CO2 respired in pasture soils showed that high respiration rates in pastures were derived almost entirely from grass root respiration and decomposition of grass residues. These results indicate that the pastures are very productive and that the larger flux of C cycling through pasture soils compared with forest soils is probably due to greater allocation of C belowground. Secondary forests had soil respiration rates similar to mature forests, and there was no correlation between soil respiration and either forest age or forest biomass. Hence, belowground allocation of C does not appear to be directly related to the stature of vegetation in this region. Variation in seasonal and annual rates of soil respiration of these forests and pastures is more indicative of flux of C through the soil rather than major net changes in ecosystem C stocks. | |||||
BibTeX:
@article{salimon_co2_2004, author = {Salimon, C. I. and Davidson, E. A. and Victoria, R. L. and Melo, A. W. F.}, title = {CO2 flux from soil in pastures and forests in southwestern Amazonia}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {833--843}, url = {://WOS:000221421600021 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00776.x/asset/j.1529-8817.2003.00776.x.pdf?v=1&t=h6hwwxtw&s=8af9905d515848ed828083cd1d51f1e5f760be93}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00776.x} } |
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Salimon, C.I. and Brown, I.F. | Secondary forests in western Amazonia: Significant sinks for carbon released from deforestation? | 2000 | Interciencia Vol. 25(4), pp. 198-202 |
article | URL |
Abstract: Conversion of tropical forests into pastures and agriculture have serious impacts on carbon allocation in ecosystems and releases carbon to the atmosphere, mainly as CO2 and CH4. The abandonment of these land uses typically results in secondary forest growth which can serve as a a sink for carbon. To determine the relative importance of this sink for the western portion of Brazil's arc of deforestation in Acre State, we measured the aboveground biomass of six secondary forests (51 to 136 Mg/ha) with ages ranging from 6 to 35 years. Based on a negative exponential model, the biomass accumulation into secondary forests in Acre is approximately 6.2* e(-0.025t) Mg ha(-1) yr(-1), of which approximately 50 percent is carbon. This simple model underestimates rates during the first ten years, but demonstrates the decreasing rate of carbon uptake with time, consistent with the classical pattern of secondary succession where slower growing tree species replace fast growing pioneer species. The time necessary to achieve half of primary forest biomass is about 30 years. Recent estimates of deforestation of Acre range between 40,000 and 50,000 ha yr(-1). For secondary forests to compensate for the carbon loss from deforestation, 80,000 to 100,000 ha would need to be abandoned each year and left to accumulate carbon for 30 years. Pilot studies indicate that secondary forests are not increasing but rather decreasing in area in Acre. Consequently, secondary forests in Acre are insignificant sinks of carbon at present. | |||||
BibTeX:
@article{salimon_secondary_2000, author = {Salimon, C. I. and Brown, I. F.}, title = {Secondary forests in western Amazonia: Significant sinks for carbon released from deforestation?}, journal = {Interciencia}, year = {2000}, volume = {25}, number = {4}, pages = {198--202}, url = {://WOS:000088084100004} } |
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Salimon, C., Sousa, E., Alin, S., Krusche, A. and Ballester, M. | Seasonal variation in dissolved carbon concentrations and fluxes in the upper Purus River, southwestern Amazon [BibTeX] |
2013 | Biogeochemistry Vol. 114(1-3), pp. 245-254 |
article | DOI |
BibTeX:
@article{salimon_seasonal_2013, author = {Salimon, C. and Sousa, E.S. and Alin, S.R. and Krusche, A.V. and Ballester, M.V.}, title = {Seasonal variation in dissolved carbon concentrations and fluxes in the upper Purus River, southwestern Amazon}, journal = {Biogeochemistry}, year = {2013}, volume = {114}, number = {1-3}, pages = {245--254}, doi = {https://doi.org/10.1007/s10533-012-9806-0} } |
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Saleska, S., Wu, J., Guan, K., Araujo, A., Huete, A., Nobre, A. and Restrepo-Coupe, N. | Dry-season greening of Amazon forests [BibTeX] |
2016 | Nature Vol. 531(7594), pp. E4-E5 |
article | |
BibTeX:
@article{saleska_dry-season_2016, author = {Saleska, S.R. and Wu, J. and Guan, K. and Araujo, A.C. and Huete, A. and Nobre, A.D. and Restrepo-Coupe, N.}, title = {Dry-season greening of Amazon forests}, journal = {Nature}, year = {2016}, volume = {531}, number = {7594}, pages = {E4--E5} } |
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Saleska, S.R., Shorter, J.H., Herndon, S., Jimenez, R., McManus, B., Munger, J.W., Nelson, D.D. and Zahniser, M.S. | What are the instrumentation requirements for measuring the isotopic composition of net ecosystem exchange of CO2 using eddy covariance methods? | 2006 | Isotopes in Environmental and Health Studies Vol. 42(2), pp. 115-133 |
article | DOI URL |
Abstract: Better quantification of isotope ratios of atmosphere-ecosystem exchange of CO 2 could substantially improve our ability to probe underlying physiological and ecological mechanisms controlling ecosystem carbon exchange, but the ability to make long-term continuous measurements of isotope ratios of exchange fluxes has been limited by measurement difficulties. In particular, direct eddy covariance methods have not yet been used for measuring the isotopic composition of ecosystem fluxes. In this article, we explore the feasibility of such measurements by (a) proposing a general criterion for judging whether a sensors performance is sufficient for making such measurements (the criterion is met when the contribution of sensor error to the flux measurement error is comparable to or less than the contribution of meteorological noise inherently associated with turbulence flux measurements); (b) using data-based numerical simulations to quantify the level of sensor precision and stability required to meet this criterion for making direct eddy covariance measurements of the C-13/C-12 ratio of CO2 fluxes above a specific ecosystem (a mid-latitude temperate forest in central Massachusetts, USA); (c) testing whether the performance of a new sensor-a prototype pulsed quantum cascade laser (QCL) based isotope-ratio absorption spectrometer (and plausible improvements thereon)-is sufficient for meeting the criterion in this ecosystem. We found that the error contribution from a prototype sensor (similar to 0.2%, 1 SD of 10 s integrations) to total isoflux measurement error was comparable to (1.5 to 2x) the irreducible 'meteorological noise inherently associated with turbulent flux measurements above this ecosystem (daytime measurement error SD of similar to 60% of flux versus meteorological noise of 30-40 % for instantaneous half-hour fluxes). Our analysis also shows that plausible instrument improvements (increase of sensor precision to similar to 0.1%, 1 SD of 10 s integrations, and increased sensor stability during the half-hour needed to integrate eddy covariance measurements) should decrease the contribution of sensor error to the point where it is less than the contribution from meteorological noise. This suggests that new sensors using QCL-based isotope ratio absorption spectroscopy should make continuous long-term observations of the isotopic composition of CO 2 fluxes via eddy covariance methods feasible. | |||||
BibTeX:
@article{saleska_what_2006, author = {Saleska, S. R. and Shorter, J. H. and Herndon, S. and Jimenez, R. and McManus, B. and Munger, J. W. and Nelson, D. D. and Zahniser, M. S.}, title = {What are the instrumentation requirements for measuring the isotopic composition of net ecosystem exchange of CO2 using eddy covariance methods?}, journal = {Isotopes in Environmental and Health Studies}, year = {2006}, volume = {42}, number = {2}, pages = {115--133}, note = {Edition: 2006/05/19}, url = {://WOS:000237679500001}, doi = {https://doi.org/10.1080/10256010600672959} } |
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Saleska, S.R., Shaw, M.R., Fischer, M.L., Dunne, J.A., Still, C.J., Holman, M.L. and Harte, J. | Plant community composition mediates both large transient decline and predicted long-term recovery of soil carbon under climate warming | 2002 | Global Biogeochemical Cycles Vol. 16(4) |
article | DOI URL |
Abstract: We integrated two methods, experimental heating and observations across natural climate gradients, to elucidate both short- and long-term climatic controls on ecosystem carbon storage and to investigate carbon-cycle feedbacks to climate in montane meadows. A 10-year heating experiment warmed and dried heated plot soils and substantially decreased (by similar to200 +/- 150 g C m(-2)) the amount of carbon stored in soil organic matter, a positive feedback to warming. In situ CO(2) flux measurements, laboratory soil incubations, and a heating-induced shift in vegetation community composition from high- to low-productivity species indicate that a decline in community productivity and resultant decrease in soil inputs from plant litter caused most of the soil carbon decrease. An alternative widely hypothesized mechanism for soil carbon decrease under warming is stimulation of soil respiration, but we observed no increase in seasonally integrated soil respiration in our experiment (soil drying inhibited microbial decomposition even as soil warming stimulated it). To extend our analysis from the short-term transient response represented by the heating experiment to the presumed long-term approximate steady state represented by natural climate gradients, we tested a hypothesized relation between vegetation community composition (which controls both litter input rate and average litter quality) and soil carbon along the climate gradient. The gradient analysis implies that the experimentally induced decline in soil carbon is transient and will eventually reverse as lower quality litter inputs from the increasingly dominant low-productivity species reduce soil respiration losses. This work shows that ecological processes can control both short- and long-term responses to climate change, confirming some model-based predictions about the importance of vegetation shifts, but challenging the widely held hypothesis that the effect of temperature change on respiration will dominate soil carbon changes. | |||||
BibTeX:
@article{saleska_plant_2002, author = {Saleska, S. R. and Shaw, M. R. and Fischer, M. L. and Dunne, J. A. and Still, C. J. and Holman, M. L. and Harte, J.}, title = {Plant community composition mediates both large transient decline and predicted long-term recovery of soil carbon under climate warming}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {4}, url = {://WOS:000180874100003}, doi = {https://doi.org/10.1029/2001gb001573} } |
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Saleska, S.R., Miller, S.D., Matross, D.M., Goulden, M.L., Wofsy, S.C., da Rocha, H.R., de Camargo, P.B., Crill, P., Daube, B.C., de Freitas, H.C., Hutyra, L., Keller, M., Kirchhoff, V., Menton, M., Munger, J.W., Pyle, E.H., Rice, A.H. and Silva, H. | Carbon in amazon forests: Unexpected seasonal fluxes and disturbance-induced losses | 2003 | Science Vol. 302(5650), pp. 1554-1557 |
article | DOI URL |
Abstract: The net ecosystem exchange of carbon dioxide was measured by eddy covariance methods for 3 years in two old-growth forest sites near Santarem, Brazil. Carbon was lost in the wet season and gained in the dry season, which was opposite to the seasonal cycles of both tree growth and model predictions. The 3-year average carbon loss was 1.3 (confidence interval: 0.0 to 2.0) megagrams of carbon per hectare per year. Biometric observations confirmed the net loss but imply that it is a transient effect of recent disturbance superimposed on long-term balance. Given that episodic disturbances are characteristic of old-growth forests, it is likely that carbon sequestration is lower than has been inferred from recent eddy covariance studies at undisturbed sites. | |||||
BibTeX:
@article{saleska_carbon_2003, author = {Saleska, S. R. and Miller, S. D. and Matross, D. M. and Goulden, M. L. and Wofsy, S. C. and da Rocha, H. R. and de Camargo, P. B. and Crill, P. and Daube, B. C. and de Freitas, H. C. and Hutyra, L. and Keller, M. and Kirchhoff, V. and Menton, M. and Munger, J. W. and Pyle, E. H. and Rice, A. H. and Silva, H.}, title = {Carbon in amazon forests: Unexpected seasonal fluxes and disturbance-induced losses}, journal = {Science}, year = {2003}, volume = {302}, number = {5650}, pages = {1554--1557}, note = {Edition: 2003/12/04}, url = {://WOS:000186802200040 http://www.sciencemag.org/content/302/5650/1554}, doi = {https://doi.org/10.1126/science.1091165} } |
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Saleska, S.R., Didan, K., Huete, A.R. and da Rocha, H.R. | Amazon forests green-up during 2005 drought | 2007 | Science Vol. 318(5850), pp. 612-612 |
article | DOI URL |
Abstract: Coupled climate-carbon cycle models suggest that Amazon forests are vulnerable to both long- and short-term droughts, but satellite observations showed a large-scale photosynthetic green-up in intact evergreen forests of the Amazon in response to a short, intense drought in 2005. These findings suggest that Amazon forests, although threatened by human-caused deforestation and fire and possibly by more severe long-term droughts, may be more resilient to climate changes than ecosystem models assume. | |||||
BibTeX:
@article{saleska_amazon_2007, author = {Saleska, Scott R. and Didan, Kamel and Huete, Alfredo R. and da Rocha, Humberto R.}, title = {Amazon forests green-up during 2005 drought}, journal = {Science}, year = {2007}, volume = {318}, number = {5850}, pages = {612--612}, note = {Edition: 2007/09/22}, url = {://WOS:000250409200036 http://www.sciencemag.org/content/318/5850/612}, doi = {https://doi.org/10.1126/science.1146663} } |
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Saleska, S., Rocha, H.d., Kruijt, B. and Nobre, A. | Ecosystem Carbon Fluxes and Amazonian Forest Metabolism [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 389-408 |
incollection | |
BibTeX:
@incollection{m_keller_ecosystem_2009, author = {Saleska, Scott and Rocha, Humberto da and Kruijt, Bart and Nobre, Antonio}, title = {Ecosystem Carbon Fluxes and Amazonian Forest Metabolism}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {389--408} } |
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Salati, E., Nobre, C.A. and dos Santos, A.A. | Amazonian deforestation: Regional and global issues | 2001 | Amazoniana-Limnologia Et Oecologia Regionalis Systemae Fluminis Amazonas Vol. 16(3-4), pp. 463-481 |
article | URL |
Abstract: How does the deforestation of Amazonia affect global and regional climates? What arc the roles of these changes on Amazonian ecosystems? We have concluded that the relation between Regional Climate Changes (RCC) and Global Climate Change (GCC) is directly associated with anthropogenic activities and therefore sensitive to social, economical and political interventions. The RCCs are caused by actions within the realm of the Brazilian sociopolitical scenario, and prone to changes through the implementation of public policies regulating the sustained use of the renewable resources. The GCCs belong to an international arena, and are caused by the high emission rates of greenhouse gases by the developed countries. The effects of the RCCs could be abated if the developed countries would endeavor to reduce the present emission levels as documented in IPCC meetings and collaborate in the implementation of a regulation to curb the carbon emissions, in accordance to the Kyoto Protocol. | |||||
BibTeX:
@article{salati_amazonian_2001, author = {Salati, E. and Nobre, C. A. and dos Santos, A. A.}, title = {Amazonian deforestation: Regional and global issues}, journal = {Amazoniana-Limnologia Et Oecologia Regionalis Systemae Fluminis Amazonas}, year = {2001}, volume = {16}, number = {3-4}, pages = {463--481}, url = {://WOS:000172677500013} } |
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Salas, W.A., Ducey, M.J., Rignot, E. and Skole, D. | Assessment of JERS-1 SAR for monitoring secondary vegetation in Amazonia: II. Spatial, temporal, and radiometric considerations for operational monitoring | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1381-1399 |
article | DOI URL |
Abstract: While the role of Synthetic Aperture Radar (SAR) in operational tropical forest monitoring has yet to be defined, it is nevertheless a critical technology for improving our understanding of deforestation and secondary vegetation in the tropics. In order to understand the role of this technology in operational monitoring a systematic evaluation, relative to other existing technologies of its performance is required. In this paper we evaluate the spatial, temporal, and noise constraints of JERS SAR data for mapping and monitoring biomass of secondary vegetation in Rondonia, Brazil. Our results indicate that the variability in stand estimates of biomass is high and that the source of the majority of the variability is not from speckle and the intrinsic texture of the secondary vegetation but likely due to differences in environmental conditions resulting in differential background scattering properties. Multitemporal analysis significantly improves biomass estimates to the point where it is possible to map changes in biomass. Slight reductions in the variability in estimates of normalized radar cross-section greatly improve biomass estimation. | |||||
BibTeX:
@article{salas_assessment_2002, author = {Salas, W. A. and Ducey, M. J. and Rignot, E. and Skole, D.}, title = {Assessment of JERS-1 SAR for monitoring secondary vegetation in Amazonia: II. Spatial, temporal, and radiometric considerations for operational monitoring}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1381--1399}, url = {://WOS:000174661900010}, doi = {https://doi.org/10.1080/01431160110092948} } |
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Sakai, R.K., Fitzjarrald, D.R., Moraes, O.L.L., Staebler, R.M., Acevedo, O.C., Czikowsky, M.J., Da Silva, R., Brait, E. and Miranda, V. | Land-use change effects on local energy, water, and carbon balances in an Amazonian agricultural field | 2004 | Global Change Biology Vol. 10(5), pp. 895-907 |
article | DOI URL |
Abstract: To study how changing agricultural practices in the eastern Amazon affect carbon, heat and water exchanges, a 20 m tower was installed in a field in August 2000. Measurements include turbulent fluxes (momentum, heat, water vapor, and CO2) using the eddy covariance (EC) approach, soil heat flux, wind, and scalar profiles (T, q, and CO2), soil moisture content, terrestrial, total solar radiation, and photosynthetically active radiation (PAR, 400-700 nm). At the beginning of the measurements, in September 2000, the field was a pasture. On November 2001, the pasture was burned, plowed, and planted in upland (nonirrigated) rice. Calm nights were the norm in this site. Anomalously low values of net ecosystem exchange (NEE) were found using the EC method, even when the common criterion u*textless0.2 m s(-1) was used to identify and exclude poor performance nights. We observed more plausible values of NEE using criterion u(*)textless0.08 m s(-1), indicating that the criterion must be revised downward for flow over surfaces smoother than forests. However, even using the lower threshold, u(*) was lower than this limit for 82% of nights, and this led to nocturnal respiration underestimates. We compensate for this difficulty by estimating the respiration rate using the nocturnal boundary layer budget method. Land-use change from pasture to rice cultivation strongly affected both diurnal rates of turbulent exchange but also the pattern of seasonal variation. Seasonal wet and dry season differences in vegetation state were clearly detected in the albedo and PAR-albedo. These reflectivity changes were accompanied by modified net radiative flux, turbulent heat flux and evaporation rates. The highest evaporation rate was observed during the rice crop, when the field had total evaporation approximately half the precipitation input, less than that of the surrounding forest. Effects of the land-cover changes were also detected in the carbon budget. For the pasture, the maximum CO2 uptake occurred in May, appreciably delayed from the start of the rainy season. After the field was plowed and the soil was exposed and there was efflux of CO2 to the atmosphere day and night for an extended period. Highest values of carbon uptake occurred during the rice plantation. Although the upland rice took up carbon at double the rate of the pasture that it replaced, the field was left fallow for much of the year, during the dry season. | |||||
BibTeX:
@article{sakai_land-use_2004, author = {Sakai, R. K. and Fitzjarrald, D. R. and Moraes, O. L. L. and Staebler, R. M. and Acevedo, O. C. and Czikowsky, M. J. and Da Silva, R. and Brait, E. and Miranda, V.}, title = {Land-use change effects on local energy, water, and carbon balances in an Amazonian agricultural field}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {895--907}, url = {://WOS:000221421600026}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00773.x} } |
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Sakaguchi, K., Zeng, X., Christoffersen, B.J., Restrepo-Coupe, N., Saleska, S.R. and Brando, P.M. | Natural and drought scenarios in an east central Amazon forest: Fidelity of the Community Land Model 3.5 with three biogeochemical models | 2011 | Journal of Geophysical Research-Biogeosciences Vol. 116 |
article | DOI URL |
Abstract: Recent development of general circulation models involves biogeochemical cycles: flows of carbon and other chemical species that circulate through the Earth system. Such models are valuable tools for future projections of climate, but still bear large uncertainties in the model simulations. One of the regions with especially high uncertainty is the Amazon forest where large-scale dieback associated with the changing climate is predicted by several models. In order to better understand the capability and weakness of global-scale land-biogeochemical models in simulating a tropical ecosystem under the present day as well as significantly drier climates, we analyzed the off-line simulations for an east central Amazon forest by the Community Land Model version 3.5 of the National Center for Atmospheric Research and its three independent biogeochemical submodels (CASA', CN, and DGVM). Intense field measurements carried out under Large Scale Biosphere-Atmosphere Experiment in Amazonia, including forest response to drought from a throughfall exclusion experiment, are utilized to evaluate the whole spectrum of biogeophysical and biogeochemical aspects of the models. Our analysis shows reasonable correspondence in momentum and energy turbulent fluxes, but it highlights three processes that are not in agreement with observations: (1) inconsistent seasonality in carbon fluxes, (2) biased biomass size and allocation, and (3) overestimation of vegetation stress to short-term drought but underestimation of biomass loss from long-term drought. Without resolving these issues the modeled feedbacks from the biosphere in future climate projections would be questionable. We suggest possible directions for model improvements and also emphasize the necessity of more studies using a variety of in situ data for both driving and evaluating land-biogeochemical models. | |||||
BibTeX:
@article{sakaguchi_natural_2011, author = {Sakaguchi, Koichi and Zeng, Xubin and Christoffersen, Bradley J. and Restrepo-Coupe, Natalia and Saleska, Scott R. and Brando, Paulo M.}, title = {Natural and drought scenarios in an east central Amazon forest: Fidelity of the Community Land Model 3.5 with three biogeochemical models}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2011}, volume = {116}, url = {://WOS:000288326300001}, doi = {https://doi.org/10.1029/2010jg001477} } |
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Saatchi, S.S., Nelson, B., Podest, E. and Holt, J. | Mapping land cover types in the Amazon Basin using 1 km JERS-1 mosaic | 2000 | International Journal of Remote Sensing Vol. 21(6-7), pp. 1201-1234 |
article | DOI URL |
Abstract: During the Global Rain Forest Mapping (GRFM) project, the JERS-1 SAR (Synthetic Aperture Radar) satellite acquired wall-to-wall image coverage of the humid tropical forests of the world. The rationale for the project was to demonstrate the application of spaceborne L-band radar in tropical forest studies. In particular, the use of orbital radar data for mapping land cover types, estimating the area of floodplains, and monitoring deforestation and forest regeneration were of primary importance. In this paper we examine the information content of the JERS-1 SAR data for mapping land cover types in the Amazon basin. More than 1500 high-resolution (12.5 m pixel spacing) images acquired during the low flood period of the Amazon river were resampled to 100 m resolution and mosaicked into a seamless image of about 8 million km(2), including the entire Amazon basin. This image was used in a classifier to generate a 1 km resolution land cover map. The inputs to the classifier were 1 km resolution mean backscatter and seven first-order texture measures derived from the 100 m data by using a 10 x 10 independent sampling window. The classification approach included two interdependent stages. First, a supervised maximum a posteriori Baysian approach classified the mean backscatter image into five general cover categories: terra firme forest (including secondary forest), savanna, inundated vegetation, open deforested areas and open water. A hierarchical decision rule based on texture measures was then applied to attempt further discrimination of known subcategories of vegetation types based on taxonomic information and woody biomass levels. True distributions of the general categories were identified from the RADAMBRASIL project vegetation maps and several field studies. Training and validation test sites were chosen from the JERS-1 image by consulting the RADAM vegetation maps. After several iterations and combining land cover types, 14 vegetation classes were successfully separated at the 1 km scale. The accuracy of the classification methodology was estimated to be 78% when using the validation sites. The results were also verified by comparison with the RADAM- and AVHRR-based 1 km resolution land cover maps. | |||||
BibTeX:
@article{saatchi_mapping_2000, author = {Saatchi, S. S. and Nelson, B. and Podest, E. and Holt, J.}, title = {Mapping land cover types in the Amazon Basin using 1 km JERS-1 mosaic}, journal = {International Journal of Remote Sensing}, year = {2000}, volume = {21}, number = {6-7}, pages = {1201--1234}, url = {://WOS:000086357700007}, doi = {https://doi.org/10.1080/014311600210146} } |
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Saatchi, S.S., Houghton, R.A., Alvala, R.C.D.S., Soares, J.V. and Yu, Y. | Distribution of aboveground live biomass in the Amazon basin | 2007 | Global Change Biology Vol. 13(4), pp. 816-837 |
article | DOI URL |
Abstract: The amount and spatial distribution of forest biomass in the Amazon basin is a major source of uncertainty in estimating the flux of carbon released from land-cover and land-use change. Direct measurements of aboveground live biomass (AGLB) are limited to small areas of forest inventory plots and site-specific allometric equations that cannot be readily generalized for the entire basin. Furthermore, there is no spaceborne remote sensing instrument that can measure tropical forest biomass directly. To determine the spatial distribution of forest biomass of the Amazon basin, we report a method based on remote sensing metrics representing various forest structural parameters and environmental variables, and more than 500 plot measurements of forest biomass distributed over the basin. A decision tree approach was used to develop the spatial distribution of AGLB for seven distinct biomass classes of lowland old-growth forests with more than 80% accuracy. AGLB for other vegetation types, such as the woody and herbaceous savanna and secondary forests, was directly estimated with a regression based on satellite data. Results show that AGLB is highest in Central Amazonia and in regions to the east and north, including the Guyanas. Biomass is generally above 300 Mg ha(-1) here except in areas of intense logging or open floodplains. In Western Amazonia, from the lowlands of Peru, Ecuador, and Colombia to the Andean mountains, biomass ranges from 150 to 300 Mg ha(-1). Most transitional and seasonal forests at the southern and northwestern edges of the basin have biomass ranging from 100 to 200 Mg ha(-1). The AGLB distribution has a significant correlation with the length of the dry season. We estimate that the total carbon in forest biomass of the Amazon basin, including the dead and belowground biomass, is 86 Pg C with +/- 20% uncertainty. | |||||
BibTeX:
@article{saatchi_distribution_2007, author = {Saatchi, S. S. and Houghton, R. A. and Alvala, R. C. Dos Santos and Soares, J. V. and Yu, Y.}, title = {Distribution of aboveground live biomass in the Amazon basin}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {4}, pages = {816--837}, url = {://WOS:000245940800007}, doi = {https://doi.org/10.1111/j.1365-2486.2007.01323.x} } |
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Saatchi, M., Xu, J., Keller, L., Yang, M., Duffy, Y., Espírito-Santo, P., Baccini, F., Chambers, A., Schimel, J. and S., D. | Seeing the forest beyond the trees. [BibTeX] |
2014 | Global Ecology and Biogeography Vol. 24(5), pp. 606-610 |
article | DOI |
BibTeX:
@article{saatchi_seeing_2014, author = {Saatchi, Mascaro, J., Xu, L., Keller, M., Yang, Y., Duffy, P., Espírito-Santo, F., Baccini, A., Chambers, J., Schimel, D., S.}, title = {Seeing the forest beyond the trees.}, journal = {Global Ecology and Biogeography}, year = {2014}, volume = {24}, number = {5}, pages = {606--610}, doi = {https://doi.org/10.1111/geb.12256} } |
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Saad, S.I., da Rocha, H.R., Silva Dias, M.A.F. and Rosolem, R. | Can the Deforestation Breeze Change the Rainfall in Amazonia? A Case Study for the BR-163 Highway Region | 2010 | Earth Interactions Vol. 14 |
article | DOI URL |
Abstract: The authors simulated the effects of Amazonian mesoscale deforestation in the boundary layer and in rainfall with the Brazilian Regional Atmospheric Modeling System (BRAMS) model. They found that both the area and shape (with respect to wind incidence) of deforestation and the soil moisture status contributed to the state of the atmosphere during the time scale of several weeks, with distinguishable patterns of temperature, humidity, and rainfall. Deforestation resulted in the development of a three-dimensional thermal cell, the so-called deforestation breeze, slightly shifted downwind to large-scale circulation. The boundary layer was warmer and drier above 1000-m height and was slightly wetter up to 2000-m height. Soil wetness affected the circulation energetics proportionally to the soil dryness (for soil wetness below similar to 0.6). The shape of the deforestation controlled the impact on rainfall. The horizontal strips lined up with the prevailing wind showed a dominant increase in rainfall, significant up to about 60 000 km(2). On the other hand, in the patches aligned in the opposite direction (north-south), there was both increase and decrease in precipitation in two distinct regions, as a result of clearly separated upward and downward branches, which caused the precipitation to increase for patches up to 15 000 km(2). The authors' estimates for the size of deforestation impacting the rainfall contributed to fill up the low spatial resolution in other previous studies. | |||||
BibTeX:
@article{saad_can_2010, author = {Saad, Sandra I. and da Rocha, Humberto R. and Silva Dias, Maria A. F. and Rosolem, Rafael}, title = {Can the Deforestation Breeze Change the Rainfall in Amazonia? A Case Study for the BR-163 Highway Region}, journal = {Earth Interactions}, year = {2010}, volume = {14}, url = {://WOS:000284311300001 http://journals.ametsoc.org/doi/abs/10.1175/2010EI351.1}, doi = {https://doi.org/10.1175/2010ei351.1} } |
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Sa, T.D.D., De Oliveira, V.C., De Araujo, A.C. and Junior, S.B. | Spectral irradiance and stomatal conductance of enriched fallows with fast-growing trees in eastern Amazonia, Brazil | 1999 | Agroforestry Systems Vol. 47(1-3), pp. 289-303 |
article | URL |
Abstract: The biomass production of both indigenous and introduced plant species in tropical fallow systems depends on the degree to which these species can acclimate to the light and water environments. Results for light spectral composition monitoring within the canopy of enriched fallows and for the leaf stomatal conductance of fast-growing leguminous trees and indigenous fallow species are presented. All measurements were made in a smallholder farm in Igarape-Acu, northeastern Para State, Brazil. Light spectral composition (330 to 1100 nm) was monitored at two heights (ground level and 1 m) in a six-year-old natural fallow, 1.5-year-old natural fallow, and 1.5-year-old fallows enriched with Acacia angustissima, Acacia mangium, Clitoria racemosa, Inga edulis, Sclerolobium paniculatum, and a mixture of these trees. Light-quality parameters including photosynthetically active radiation, phytochrome active radiation, and blue active radiation changed most drastically in the stands enriched with A. mangium. Stomatal conductance was higher for A. mangium than the other trees and four common indigenous fallow vegetation species (Phenakospermum guyannense, Davilla rugosa, Lacistema pubescens, and Myrcia bracteata). Results suggest that the enrichment of fallows with A. mangium may promote changes in light and water vapor exchange regimes, with potential effects on species diversity in fallows. | |||||
BibTeX:
@article{sa_spectral_1999, author = {Sa, T. D. D. and De Oliveira, V. C. and De Araujo, A. C. and Junior, S. B.}, title = {Spectral irradiance and stomatal conductance of enriched fallows with fast-growing trees in eastern Amazonia, Brazil}, journal = {Agroforestry Systems}, year = {1999}, volume = {47}, number = {1-3}, pages = {289--303}, url = {://WOS:000084972800018} } |
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Sá, S.S.d., Palm, B.B., Campuzano-Jost, P., Day, D.A., Newburn, M.K., Hu, W., Isaacman-VanWertz, G., Yee, L.D. and Ryan Thalman b, S.C.P.A.A.H.G.A.O.M.R.A.F.S.F.M.J.E.S.S.R.S.J.J.D.S.M.L.A.J.L.J.and.S.T.M.J.B. | Influence of urban pollution on the production of organic particulate matter from isoprene epoxydiols in central Amazonia [BibTeX] |
2017 | Atmos. Chem. Phys. Vol. 17, pp. 6611-6629 |
article | DOI |
BibTeX:
@article{sa_influence_2017, author = {Sá, Suzane S. de and Palm, Brett B. and Campuzano-Jost, Pedro and Day, Douglas A. and Newburn, Matthew K. and Hu, Weiwei and Isaacman-VanWertz, Gabriel and Yee, Lindsay D. and Ryan Thalman, b, Samara Carbone, Paulo Artaxo, Allen H. Goldstein, Antonio O. Manzi, Rodrigo A. F. Souza, Fan Mei, John E. Shilling, Stephen R. Springston, JianWang, Jason D. Surratt, M. Lizabeth Alexander, Jose L. Jimenez, and Scot T. Martin, Joel Brito6}, title = {Influence of urban pollution on the production of organic particulate matter from isoprene epoxydiols in central Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2017}, volume = {17}, pages = {6611--6629}, doi = {https://doi.org/10.5194/acp-17-6611-2017} } |
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Sá, M.O. and al. , e. | Interações Biofísicas entre a Floresta e a Atmosfera na Região do Alto Rio Negro [BibTeX] |
2012 | book | ||
BibTeX:
@book{inpa_interacoes_2012, author = {Sá, M. O. and al., et.}, title = {Interações Biofísicas entre a Floresta e a Atmosfera na Região do Alto Rio Negro}, publisher = {EDITORA INPA}, year = {2012}, note = {Section: p.81} } |
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Sá, M.d.O., Leal, L.d.S.M., Campos, J.G., Araújo, A.C.d., Silva, P.R.T.d., Silva, M.M.d., Pauletto, D., Oliveira, M.B.L.d., Fernandes, M.R.P.S., Diniz, M.M. and Manzi, A.O. | Estudo do clima e interações entre a floresta e a atmosfera, no parque nacional do pico da neblina, São Gabriel da Cachoeira, AM [BibTeX] |
2012 | Vol. 1Desvendando as fronteiras do conhecimento na região amazônica do Alto Rio Negro, pp. 29-43 |
incollection | |
BibTeX:
@incollection{luiz_augusto_gomes_de_souza_estudo_2012, author = {Sá, Marta de Oliveira and Leal, Leila do Socorro Monteiro and Campos, José Galúcio and Araújo, Alessandro Carioca de and Silva, Paulo Ricardo Teixeira da and Silva, Mauro Mendonça da and Pauletto, Daniela and Oliveira, Maria Betânia Leal de and Fernandes, Maria Rosimar Pereira Soares and Diniz, Mékio Menezes and Manzi, Antonio Ocimar}, title = {Estudo do clima e interações entre a floresta e a atmosfera, no parque nacional do pico da neblina, São Gabriel da Cachoeira, AM}, booktitle = {Desvendando as fronteiras do conhecimento na região amazônica do Alto Rio Negro}, publisher = {EDITORA INPA}, year = {2012}, volume = {1}, pages = {29--43}, note = {Section: 1} } |
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Sá, L. and Pachêco, V. | Wind velocity above and inside Amazonian rain forest in Rondônia [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3a), pp. 50-58 |
article | |
BibTeX:
@article{sa_wind_2006, author = {Sá, L.D.A. and Pachêco, V.B.}, title = {Wind velocity above and inside Amazonian rain forest in Rondônia}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3a}, pages = {50--58} } |
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Sá, L. and Pachêco, V. | Relação de similaridade para os perfis de velocidade média do vento dentro da copa da floresta amazônica em Rondônia [BibTeX] |
2001 | Revista Brasileira de Meteorologia Vol. 16, pp. 81-89 |
article | |
BibTeX:
@article{sa_relacao_2001, author = {Sá, L.D.A. and Pachêco, V.B.}, title = {Relação de similaridade para os perfis de velocidade média do vento dentro da copa da floresta amazônica em Rondônia}, journal = {Revista Brasileira de Meteorologia}, year = {2001}, volume = {16}, pages = {81--89} } |
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Sá, L. and Andrade, E. | Curvatura do perfil vertical de temperatura potencial virtual acima do pantanal em períodos noturnos: diferenças entre as estações seca e úmida [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 413-417 |
article | |
BibTeX:
@article{sa_curvatura_2006, author = {Sá, L.D.A. and Andrade, E.S.}, title = {Curvatura do perfil vertical de temperatura potencial virtual acima do pantanal em períodos noturnos: diferenças entre as estações seca e úmida}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {413--417} } |
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Sa, L.D.A., Alvala, R.C.S., Arai, E., Arlino, P.R.A., Barbosa, A.C., Bolzan, M.J.A., Bonfim, A., Castro, W.E., Dias, M., Prasad, G., Gielow, R., da Costa, A.C.L., Manzi, A.O., Nogueira, J.L.M., Melo, J., Moura, R.G., Rosa, L.E., Rossato, L., von Randow, C. and Ams | General aspects of the Rebio-Jaru Amazon forest Micrometeorological Tower LBA wet season campaign and preliminary results [BibTeX] |
2000 | 15th Conference on Hydrology, pp. 369-372 | incollection | URL |
BibTeX:
@incollection{sa_general_2000, author = {Sa, L. D. A. and Alvala, R. C. S. and Arai, E. and Arlino, P. R. A. and Barbosa, A. C. and Bolzan, M. J. A. and Bonfim, A. and Castro, W. E. and Dias, Mafs and Prasad, Gssd and Gielow, R. and da Costa, A. C. L. and Manzi, A. O. and Nogueira, J. L. M. and Melo, J. and Moura, R. G. and Rosa, L. E. and Rossato, L. and von Randow, C. and Ams}, title = {General aspects of the Rebio-Jaru Amazon forest Micrometeorological Tower LBA wet season campaign and preliminary results}, booktitle = {15th Conference on Hydrology}, year = {2000}, pages = {369--372}, url = {://WOS:000168561100110} } |
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Russell P. J. Rasch, G.M.M.R.B.J.J.S.P.L.M.L.D.S.N.E.V.A.C.J.P.B.R.J.N.K.C.J.M.P.A.J.M.and.M.G.M.L. | Ecosystem Impacts of Geoengineering: A Review for Developing a Science Plan [BibTeX] |
2012 | Ambio | article | DOI |
BibTeX:
@article{russell_ecosystem_2012, author = {Russell, P. J. Rasch, G. M. Mace, R. B. Jackson, J. Shepherd, P. Liss, M. Leinen, D. Schimel, N. E. Vaughan, A. C. Janetos, P. Boyd, R., J. Norby, K. Caldeira, J. Merikanto, P. Artaxo, J. Melillo, and M. G. Morgan, L.M.}, title = {Ecosystem Impacts of Geoengineering: A Review for Developing a Science Plan}, journal = {Ambio}, year = {2012}, doi = {https://doi.org/10.1007/s13280-012-0258-5} } |
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Rummel, U., Ammann, C., Kirkman, G.A., Moura, M.A.L., Foken, T., Andreae, M.O. and Meixner, F.X. | Seasonal variation of ozone deposition to a tropical rain forest in southwest Amazonia | 2007 | Atmospheric Chemistry and Physics Vol. 7(20), pp. 5415-5435 |
article | URL |
Abstract: Within the project EUropean Studies on Trace gases and Atmospheric CHemistry as a contribution to Large-scale Biosphere-atmosphere experiment in Amazonia (LBA-EUSTACH), we performed tower-based eddy covariance measurements of O-3 flux above an Amazonian primary rain forest at the end of the wet and dry season. Ozone deposition revealed distinct seasonal differences in the magnitude and diel variation. In the wet season, the rain forest was an effective O-3 sink with a mean daytime (midday) maximum deposition velocity of 2.3 cm(-)1, and a corresponding O-3 flux of -11 nmol m(-2)s(-1). At the end of the dry season, the ozone mixing ratio was about four times higher (up to maximum values of 80 ppb) than in the wet season, as a consequence of strong regional biomass burning activity. However, the typical maximum daytime deposition flux was very similar to the wet season. This results from a strong limitation of daytime O-3 deposition due to reduced plant stomatal aperture as a response to large values of the specific humidity deficit. As a result, the average midday deposition velocity in the dry burning season was only 0.5 cm s(-1). The large diel ozone variation caused large canopy storage effects that masked the true diel variation of ozone deposition mechanisms in the measured eddy covariance flux, and for which corrections had to be made. In general, stomatal aperture was sufficient to explain the largest part of daytime ozone deposition. However, during nighttime, chemical reaction with nitrogen monoxide (NO) was found to contribute substantially to the O-3 sink in the rain forest canopy. Further contributions were from non-stomatal plant uptake and other processes that could not be clearly identified. Measurements, made simultaneously on a 22 years old cattle pasture enabled the spatially and temporally direct comparison of O-3 dry deposition values from this site with typical vegetation cover of deforested land in southwest Amazonia to the results from the primary rain forest. The mean ozone deposition to the pasture was found to be systematically lower than that to the forest by 30% in the wet and 18% in the dry season. | |||||
BibTeX:
@article{rummel_seasonal_2007, author = {Rummel, U. and Ammann, C. and Kirkman, G. A. and Moura, M. A. L. and Foken, T. and Andreae, M. O. and Meixner, F. X.}, title = {Seasonal variation of ozone deposition to a tropical rain forest in southwest Amazonia}, journal = {Atmospheric Chemistry and Physics}, year = {2007}, volume = {7}, number = {20}, pages = {5415--5435}, url = {://WOS:000251239200011} } |
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Rummel, U., Ammann, C., Gut, A., Meixner, F.X. and Andreae, M.O. | Eddy covariance measurements of nitric oxide flux within an Amazonian rain forest | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: NO flux measurements by the eddy covariance technique were performed within a tropical rain forest 1 m and 11 m above the forest floor. A fast-response chemiluminescence NO analyzer with a sampling tube of 25 m length was used for the gas measurements. Nighttime similarity between the cospectra of sensible heat and the NO flux offered the possibility to quantify the high-frequency attenuation of the NO eddy covariance by spectral analysis. Integrated flux correction factors of about 21% for the system at 1 m and 5% for the one at 11 m above ground were calculated by transfer functions adopted from the literature and confirmed experimentally. For an independent validation the results of the eddy covariance system were compared with the NO soil emissions obtained by dynamic chambers. For nighttime averages, good agreement within 10% was found. The obtained NO fluxes were 3.5 +/- 0.14 and 4.8 +/- 0.39 ng N m(-2) s(-1) for the two investigated periods at 1 and 11 m heights, respectively. During the day, chemical reaction with ozone entrained from aloft reduced the fraction of the soil-emitted NO that reached the measuring height of the eddy covariance system. The average flux showed a reduction of 48% at 1 m and 92% at 11 m height compared to the corresponding soil emission measured by the chamber system. | |||||
BibTeX:
@article{rummel_eddy_2002, author = {Rummel, U. and Ammann, C. and Gut, A. and Meixner, F. X. and Andreae, M. O.}, title = {Eddy covariance measurements of nitric oxide flux within an Amazonian rain forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200007}, doi = {https://doi.org/10.1029/2001jd000520} } |
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Ruivo, M. and Silva, R.d. | Interações bióticas e abióticas no nordeste do Pará [BibTeX] |
2017 | Boletim Museu Paraense Emílio Goeldi Ciencias Naturais Vol. 11(3), pp. 301-302 |
article | |
BibTeX:
@article{ruivo_interacoes_2017, author = {Ruivo, M.L.P. and Silva, R.R. da}, title = {Interações bióticas e abióticas no nordeste do Pará}, journal = {Boletim Museu Paraense Emílio Goeldi Ciencias Naturais}, year = {2017}, volume = {11}, number = {3}, pages = {301--302} } |
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Ruivo Amaral, I. and Ribeiro E.L.C. & Guedes, A.M. | Os solos de uma toposseqüência na Ilha de Algodoal/Maiandeua, Nordeste do Estado do Pará: composição química e produção de matéria orgânica [BibTeX] |
2002 | Acta Amazonica Vol. 32, pp. 257 - 266 |
article | |
BibTeX:
@article{ruivo_os_2002, author = {Ruivo, Amaral, I.G.; Ribeiro, E.L.C. & Guedes, A.L., M.L.P.}, title = {Os solos de uma toposseqüência na Ilha de Algodoal/Maiandeua, Nordeste do Estado do Pará: composição química e produção de matéria orgânica}, journal = {Acta Amazonica}, year = {2002}, volume = {32}, pages = {257 -- 266} } |
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Ruivo, M.d.L.P., Barreiros, J.A.P., Bonaldo, A.B., da Silva, R.M., Sa, L.D.A. and Lopes, E.L.N. | LBA-ESECAFLOR artificially induced drought in Caxiuana Reserve, Eastern Amazonia: Soil properties and litter spider fauna | 2007 | Earth Interactions Vol. 11 |
article | URL |
Abstract: A review is presented of soil properties and litter fauna of an experimental site in the Caxiuana forest, eastern Amazonia, as a contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). This study's main scientific goal is to compare some biogeochemical soil properties of an undisturbed forest ecosystem with those of an experimental (1 ha) plot in which rainfall was artificially excluded to simulate drought [the Efeitos da Seca da Floresta (ESECAFLOR) experiment]. A second scientific objective is to investigate the space variability of soil profile characteristics in the experimental sites, particularly organic carbon concentration, moisture, and texture. It is expected that such soil property variability influences greatly the distribution of several biological species such as spiders. To investigate such effects in the litter spider community, we applied percentual complementarity and Simpson diversity index to available data. Our results suggest that a faunal transition was under way in the treatment plot, shifting from a rich and even community to a less diverse one. | |||||
BibTeX:
@article{ruivo_lba-esecaflor_2007, author = {Ruivo, M. de L. P. and Barreiros, J. A. P. and Bonaldo, A. B. and da Silva, R. M. and Sa, L. D. A. and Lopes, E. L. N.}, title = {LBA-ESECAFLOR artificially induced drought in Caxiuana Reserve, Eastern Amazonia: Soil properties and litter spider fauna}, journal = {Earth Interactions}, year = {2007}, volume = {11}, url = {://WOS:000248071200001} } |
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Ruezzene, C.B., Aguiar, R.G., Svierzoski, N.D.S., Castro, B.S., Barbino, G.C. and Webler, A.D. | Índice de Área Foliar e Biomassa pelo Método Direto em uma Área de Pastagem na Amazônia Ocidental [BibTeX] |
2018 | Vol. 1(1)Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental, pp. 119-127 |
incollection | |
BibTeX:
@incollection{org_indice_2018, author = {Ruezzene, C. B. and Aguiar, R. G. and Svierzoski, N. D. S. and Castro, B. S. and Barbino, G. C. and Webler, A. D.}, title = {Índice de Área Foliar e Biomassa pelo Método Direto em uma Área de Pastagem na Amazônia Ocidental}, booktitle = {Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental}, publisher = {Appris Editora}, year = {2018}, volume = {1}, number = {1}, pages = {119--127} } |
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Rudorff, C.M., Melack, J.M., MacIntyre, S., Barbosa, C.C.F. and Novo, E. | Seasonal and spatial variability of CO(2) emission from a large floodplain lake in the lower Amazon | 2012 | Journal of Geophysical Research-Biogeosciences Vol. 117(G1) |
article | DOI URL |
Abstract: The inundation status of the Amazon floodplain affects biogenic gas production and evasion. We analyzed spatial variability of dissolved CO(2) concentration and gas evasion in a large floodplain lake in the lower reach of the Amazon River in four hydrological phases. We calculated surficial CO(2) concentrations from measurements of pH, dissolved inorganic carbon, temperature, and conductivity and used meteorological data to calculate gas transfer coefficients to estimate CO(2) evasion. Gas transfer coefficients that take into account both wind and heating and cooling at the lake's surface are on the order of 10 cm hr(-1), approximately four times higher than values previously used in regional estimates of gas evasion from lakes on the Amazon floodplain. Supersaturation of CO(2) occurred throughout the lake and was higher in the littoral zone and in regions receiving Amazon River inflows. CO(2) concentration was reduced in regions with phytoplankton blooms. The range of CO(2) concentrations was least at low water, 47 mu M to 233 mu M, and largest at high water, 1 mu M to 656 mu M; the average annual value was 125 mu M. We estimate mean (+/- standard deviation) fluxes from open-water in L. Curuai to the atmosphere of 44 +/- 15, 348 +/- 13, 371 +/- 23, and 364 +/- 20 mmol CO(2) m(-2) d(-1) during receding, low, rising, and high water, respectively. The error associated with these values reflects, for each hydrological phase, the spatial variation in CO(2) concentration in L. Curuai, a likely range in atmospheric CO(2) levels and temporal variations in gas transfer coefficient within 10-day periods. | |||||
BibTeX:
@article{rudorff_seasonal_2012, author = {Rudorff, C. M. and Melack, J. M. and MacIntyre, S. and Barbosa, C. C. F. and Novo, E.M.L.M.}, title = {Seasonal and spatial variability of CO(2) emission from a large floodplain lake in the lower Amazon}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2012}, volume = {117}, number = {G1}, url = {://WOS:000296150600001}, doi = {https://doi.org/10.1029/2011JG001919} } |
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Rudorff Novo, E. and Galvão L. S., C. | Análise derivativa de dados hiperespectrais medidos em nível de campo e orbital para caracterizar a composição de águas opticamente complexas na Amazônia [BibTeX] |
2007 | Acta Amazonica Vol. 37, pp. 279-290 |
article | |
BibTeX:
@article{rudorff_alise_2007, author = {Rudorff, Novo, E.M.L.M. ; Galvão, L. S., C.M.}, title = {Análise derivativa de dados hiperespectrais medidos em nível de campo e orbital para caracterizar a composição de águas opticamente complexas na Amazônia}, journal = {Acta Amazonica}, year = {2007}, volume = {37}, pages = {279--290} } |
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Rudel, T.K., Coomes, O.T., Moran, E., Achard, F., Angelsen, A., Xu, J.C. and Lambin, E. | Forest transitions: towards a global understanding of land use change | 2005 | Global Environmental Change-Human and Policy Dimensions Vol. 15(1), pp. 23-31 |
article | DOI URL |
Abstract: Places experience forest transitions when declines in forest cover cease and recoveries in forest cover begin. Forest transitions have occurred in two, sometimes overlapping circumstances. In some places economic development has created enough non-farm jobs to pull farmers off of the land, thereby inducing the spontaneous regeneration of forests in old fields. In other places a scarcity of forest products has prompted governments and landowners to plant trees in some fields. The transitions do little to conserve biodiversity, but they do sequester carbon and conserve soil, so governments should place a high priority on promoting them. © 2005 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{rudel_forest_2005, author = {Rudel, T. K. and Coomes, O. T. and Moran, E. and Achard, F. and Angelsen, A. and Xu, J. C. and Lambin, E.}, title = {Forest transitions: towards a global understanding of land use change}, journal = {Global Environmental Change-Human and Policy Dimensions}, year = {2005}, volume = {15}, number = {1}, pages = {23--31}, url = {://WOS:000228902700004}, doi = {https://doi.org/10.1016/j.gloenvcha.2004.11.001} } |
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Rubinstein, A. and Vasconcelos, H.L. | Leaf-litter decomposition in Amazonian forest fragments [BibTeX] |
2005 | Journal of Tropical Ecology Vol. 21, pp. 699-702 |
article | DOI URL |
BibTeX:
@article{rubinstein_leaf-litter_2005, author = {Rubinstein, A. and Vasconcelos, H. L.}, title = {Leaf-litter decomposition in Amazonian forest fragments}, journal = {Journal of Tropical Ecology}, year = {2005}, volume = {21}, pages = {699--702}, url = {://WOS:000233216500011}, doi = {https://doi.org/10.1017/s0266467405002762} } |
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Roy, S.B., Weaver, C.P., Nolan, D.S. and Avissar, R. | A preferred scale for landscape forced mesoscale circulations? | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D22) |
article | DOI URL |
Abstract: The Regional Atmospheric Modeling System was used in two previous studies to simulate mesoscale circulations forced by surface heterogeneity in the Central U. S. and Amazonia. In this work, spectral analysis is used to compare the horizontal length scales of these simulated circulations with the scale of the surface heterogeneity. For both cases, the organized mesoscale circulations are confined within a preferred length scale range (10-20 km) that is significantly different from the dominant length scale of the surface heterogeneity. Multiscale landscape patchiness in these two regions tend to produce eddies at a wide range of scales, but the land-atmosphere interaction processes act as a medium-pass filter to select intermediate-scale circulations. This scale of response remains relatively unchanged despite significant day-to-day variations in the synoptic situation and the mean surface heat flux. | |||||
BibTeX:
@article{roy_preferred_2003, author = {Roy, S. B. and Weaver, C. P. and Nolan, D. S. and Avissar, R.}, title = {A preferred scale for landscape forced mesoscale circulations?}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D22}, url = {://WOS:000186653900001}, doi = {https://doi.org/10.1029/2002jd003097} } |
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Roy, S.B., Hurtt, G.C., Weaver, C.P. and Pacala, S.W. | Impact of historical land cover change on the July climate of the United States | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D24) |
article | DOI URL |
Abstract: We used the Regional Atmospheric Modeling System (RAMS) model to investigate the possible impact of land cover change on the July climate of the coterminous United States over the last 290 years. Vegetation data were estimated using the Ecosystem Demography model. The observed change in land cover leads to a weak warming along the Atlantic coast and a strong cooling of more than 1 K over the Midwest and the Great Plains region. The precipitation signal is weaker and shows some reduction in the Midwest because of changes in the patterns of large-scale moisture advection. | |||||
BibTeX:
@article{roy_impact_2003, author = {Roy, S. B. and Hurtt, G. C. and Weaver, C. P. and Pacala, S. W.}, title = {Impact of historical land cover change on the July climate of the United States}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D24}, url = {://WOS:000187865600002}, doi = {https://doi.org/10.1029/2003jd003565} } |
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Roy, S.B. and Avissar, R. | Impact of land use/land cover change on regional hydrometeorology in Amazonia | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] A high-resolution mesoscale model was used to investigate the impact of deforestation in Amazonia. Coherent mesoscale circulations were triggered by the surface heterogeneity; synoptic flow did not eliminate the circulations but advected them away from the location where they were generated. This was substantiated by satellite-derived cloud images. These circulations affected the transport of moisture and heat at the synoptic scale and can affect climate. Adequate parameterizations for these processes should be included in GCMs for more accurate climate simulations. | |||||
BibTeX:
@article{roy_impact_2002, author = {Roy, S. B. and Avissar, R.}, title = {Impact of land use/land cover change on regional hydrometeorology in Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180336500002}, doi = {https://doi.org/10.1029/2000jd000266} } |
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Roy, S.B. and Avissar, R. | Scales of response of the convective boundary layer to land-surface heterogeneity | 2000 | Geophysical Research Letters Vol. 27(4), pp. 533-536 |
article | URL |
Abstract: The convective boundary layer (CBL) over domains with meso-gamma-scale (2-20 km) heterogeneity is characterized by preferentially located, organized rolls of characteristic size equivalent to the length-scale of the heterogeneity. Additionally, random turbulent thermals also develop when the length-scale of the heterogeneity exceeds 5-10 km. This is due to a complex interaction between the horizontal pressure gradient generated by the heterogeneity and the buoyancy forcing. Consequently, the corresponding wavelet spectrum exhibits two peaks - one representing the turbulent thermals at a characteristic scale of about 1.5 times the CBL height and another denoting the organized eddies at a scale similar: to that of the heterogeneity. This implies that subgrid-scale parameterizations in models with grid size larger than 5-10 km, which account only for random turbulence, are inadequate for heterogeneous domains. Also, this study may provide a more objective classification of scales of atmospheric processes. | |||||
BibTeX:
@article{roy_scales_2000, author = {Roy, S. B. and Avissar, R.}, title = {Scales of response of the convective boundary layer to land-surface heterogeneity}, journal = {Geophysical Research Letters}, year = {2000}, volume = {27}, number = {4}, pages = {533--536}, url = {://WOS:000085343600023} } |
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Rowland, R., Harper, A., Christoffersen, B., Galbraith, D., Imbuzeiro, H., Powell, T., Doughty, C., Levine, N., Malhi, Y., Saleska, S., Moorcroft, P., Meir, P. and Williams, M. | Modelling climate change responses in tropical forests: similar productivity estimates across five models, but different mechanisms and responses [BibTeX] |
2015 | Geoscientific model development Vol. 8, pp. 1-14 |
article | DOI |
BibTeX:
@article{rowland_modelling_2015, author = {Rowland, R. and Harper, A. and Christoffersen, BO. and Galbraith, DR. and Imbuzeiro, HMA. and Powell, TL. and Doughty, C. and Levine, NM. and Malhi, Y. and Saleska, SR. and Moorcroft, PR. and Meir, P. and Williams, M.}, title = {Modelling climate change responses in tropical forests: similar productivity estimates across five models, but different mechanisms and responses}, journal = {Geoscientific model development}, year = {2015}, volume = {8}, pages = {1--14}, doi = {https://doi.org/10.5194/gmd-8-1-2015} } |
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Rowland, L., Stahl, C., Bonal, D., Siebicke, L., Williams, M. and Meir, P. | The Response of Tropical Rainforest Dead Wood Respiration to Seasonal Drought [BibTeX] |
2013 | Ecosystems Vol. 16(7), pp. 1294-1309 |
article | DOI |
BibTeX:
@article{rowland_response_2013, author = {Rowland, L. and Stahl, C. and Bonal, D. and Siebicke, L. and Williams, M. and Meir, P.}, title = {The Response of Tropical Rainforest Dead Wood Respiration to Seasonal Drought}, journal = {Ecosystems}, year = {2013}, volume = {16}, number = {7}, pages = {1294--1309}, doi = {https://doi.org/10.1007/s1002} } |
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Rowland, L., Malhi, Y., Silva-Espejo, J.E., Farfán-Amézquita, F., Halladay, K., Doughty, C.E., Meir, P. and Phillips, O.L. | The sensitivity of wood production to seasonal and interannual variations in climate in a lowland Amazonian rainforest [BibTeX] |
2014 | Oecologia Vol. 174, pp. 295-306 |
article | |
BibTeX:
@article{rowland_sensitivity_2014, author = {Rowland, Lucy and Malhi, Y. and Silva-Espejo, J. E. and Farfán-Amézquita, F. and Halladay, K. and Doughty, C. E. and Meir, P. and Phillips, O. L.}, title = {The sensitivity of wood production to seasonal and interannual variations in climate in a lowland Amazonian rainforest}, journal = {Oecologia}, year = {2014}, volume = {174}, pages = {295--306} } |
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Rowland, L., Lobo do Vale, R., Christoffersen, B., Melem, E., Kruijt, B., Vasconcelos, S., Domingues, T., Binks, O., Oliveira, A., Metcalfe, D., da Costa, A., Mencuccini, M. and Meir, P. | After more than a decade of soil moisture deficit, tropical rainforest trees maintain photosynthetic capacity, despite increased leaf respiration [BibTeX] |
2015 | Global Change Biology Vol. 21(12), pp. 4662-72 |
article | DOI |
BibTeX:
@article{rowland_after_2015, author = {Rowland, L. and Lobo do Vale, R.L. and Christoffersen, B. and Melem, EA. and Kruijt, B. and Vasconcelos, S.S. and Domingues, T. and Binks, O.J. and Oliveira, A.R. and Metcalfe, D.B. and da Costa, A.C.L. and Mencuccini, M. and Meir, P.}, title = {After more than a decade of soil moisture deficit, tropical rainforest trees maintain photosynthetic capacity, despite increased leaf respiration}, journal = {Global Change Biology}, year = {2015}, volume = {21}, number = {12}, pages = {4662--72}, doi = {https://doi.org/10.1111/gcb.13035} } |
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Rowland, L., da Costa A. C., L., Oliveira A. A., R., Oliveira., R., Bittencourt, P., Costa, P.B., Giles, A.L., Sosa, A.I., Coughline, I., Godley, J., Vasconcelos, S.S., Junior, J.A.S., Ferreira, L.V., Mencuccini, M. and Meir, P. | Drought stress and tree size determine stem CO2 efflux in tropical forests [BibTeX] |
2018 | New Phytologist Vol. 218(4), pp. 1393-1405 |
article | DOI |
BibTeX:
@article{rowland_drought_2018, author = {Rowland, L. and L., da Costa A. C. and R., Oliveira A. A. and Oliveira., R.S. and Bittencourt, P.L. and Costa, P. B. and Giles, A. L. and Sosa, A. I. and Coughline, I. and Godley, J.; and Vasconcelos, S. S. and Junior, J. A. S. and Ferreira, L. V. and Mencuccini, M. and Meir, P.}, title = {Drought stress and tree size determine stem CO2 efflux in tropical forests}, journal = {New Phytologist}, year = {2018}, volume = {218}, number = {4}, pages = {1393--1405}, doi = {https://doi.org/10.1111/nph.15024} } |
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Rowland, L., Hill, T., Stahl, C., Siebicke, L., Burban, B., Zaragoza-Castells, J., Ponton, S., Bonal., D., Meir, P. and Williams, M. | Evidence for strong seasonality in the carbon storage and carbon use efficiency of an Amazonian forest [BibTeX] |
2014 | Global Change Biology Vol. 20(3), pp. 979-991 |
article | |
BibTeX:
@article{rowland_evidence_2014, author = {Rowland, L. and Hill, T. and Stahl, C. and Siebicke, L. and Burban, B. and Zaragoza-Castells, J. and Ponton, S. and D., Bonal. and Meir, P. and Williams, M.}, title = {Evidence for strong seasonality in the carbon storage and carbon use efficiency of an Amazonian forest}, journal = {Global Change Biology}, year = {2014}, volume = {20}, number = {3}, pages = {979--991} } |
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Rowland, L., Costa, A.C.L.d., Oliveira, A.A.R., Almeida, S.S., Ferreira, L.V., Malhi, Y., Metcalfe, D.B., Mencuccini, M., Grace, J. and Meir, P. | Shock and stabilisation following long-term drought in tropical forest from 15 years of litterfall dynamics [BibTeX] |
2018 | Journal of Ecology Vol. 106(4), pp. 1673-1682 |
article | DOI |
BibTeX:
@article{rowland_shock_2018, author = {Rowland, L. and Costa, A. C. L. da and Oliveira, A. A. R. and Almeida, S. S. and Ferreira, L. V. and Malhi, Y. and Metcalfe, D. B. and Mencuccini, M. and Grace, J. and Meir, P.}, title = {Shock and stabilisation following long-term drought in tropical forest from 15 years of litterfall dynamics}, journal = {Journal of Ecology}, year = {2018}, volume = {106}, number = {4}, pages = {1673--1682}, doi = {https://doi.org/10.1111/1365-2745.12931} } |
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Rowland, L., Costa, A.C.L.d., Galbraith, D.R., Oliveira, R.S., Binks, O.J., Oliveira, A.A.R., Pullen, A.M., Doughty, C.E., Metcalfe, D.B., Vasconcelos, S.S., Ferreira, L.V., Malhi, Y., Grace, J., Mencuccini, M. and Meir, P. | Death from drought in tropical forests is triggered by hydraulics not carbon starvation [BibTeX] |
2015 | Nature Vol. 528, pp. 119-122 |
article | DOI |
BibTeX:
@article{rowland_death_2015, author = {Rowland, L. and Costa, A. C. L. da and Galbraith, D. R. and Oliveira, R. S. and Binks, O. J. and Oliveira, A. A. R. and Pullen, A. M. and Doughty, C. E. and Metcalfe, D. B. and Vasconcelos, S. S. and Ferreira, L. V. and Malhi, Y. and Grace, J. and Mencuccini, M. and Meir, P.}, title = {Death from drought in tropical forests is triggered by hydraulics not carbon starvation}, journal = {Nature}, year = {2015}, volume = {528}, pages = {119--122}, doi = {https://doi.org/10.1038/nature15539} } |
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Roulet, M., Lucotte, M., Guimaraes, J.R.D. and Rheault, I. | Methylmercury in water, seston, and epiphyton of an Amazonian river and its floodplain, Tapajos River, Brazil | 2000 | Science of the Total Environment Vol. 261(1-3), pp. 43-59 |
article | DOI URL |
Abstract: Levels and accumulation of MeHg were characterized in filtered water, suspended organo-mineral matter, phytoplankton, zooplankton and epiphyton during the dry season and the wet season. In open water of the lentic and lotic ecosystems, the MeHg in filtered water (textless 0.2 mu m) was near or below the detection limit (textless 0.02-0.03 ng/l). These concentrations represent textless5% of the Hg-tot. content in filtered water. Inundated forests (Igapo) and macrophyte floating mats were the only sites where MeHg was significantly detected (0.07-0.24 ng/l), representing 3-22% of the Hg-tot. in filtered water. MeHg concentrations in organo-mineral suspended matter (2-26 ng/g dry wt. representing 0.6-7.3% of Hg-tot.) were correlated with the N content but not with the C content. Data suggest that MeHg enrichment of suspended matter is strongly influenced by the presence of degraded planktonic remains relatively rich in N and MeHg. In zooplankton, MeHg concentrations (20-140 ng/g dry wt.) increased from the dry season to the end of the wet season. This increase was followed by higher proportions of MeHg during the wet season in comparison to the dry season (15-40 to 50-70% of the Hg-tot.). The epiphytic material collected from the roots of macrophyte floating mats contained 2-8.5 ng/g dry wt. of MeHg. The proportion of MeHg to Hg-tot. in epiphyton (1.5-8.3%) correlated with its C and N contents. The data suggest a greater bioavailability of MeHg in the Tapajos River ecosystems due to the seasonal increase in water level and the consequent inundation of the floodplain. Inundation favours the development of large macrophyte floating mats which increases the bioavailability of epiphyton to herbivorous/detritivorous fish. The root zone of floating macrophytes and the flooded organic horizon of the Igapo forest are the only sites along the Tapajos River where significant MeHg can be detected in the water column and sediment. This new study supports the hypothesis that MeHg production and transfer to the first link of the food chain in Amazonian river systems is closely related to organic matter biogeochemistry in the floodplain environment. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{roulet_methylmercury_2000, author = {Roulet, M. and Lucotte, M. and Guimaraes, J. R. D. and Rheault, I.}, title = {Methylmercury in water, seston, and epiphyton of an Amazonian river and its floodplain, Tapajos River, Brazil}, journal = {Science of the Total Environment}, year = {2000}, volume = {261}, number = {1-3}, pages = {43--59}, note = {Edition: 2000/10/19}, url = {://WOS:000089587200005}, doi = {https://doi.org/10.1016/s0048-9697(00)00594-5} } |
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Roulet, M., Lucotte, M., Farella, N., Serique, G., Coelho, H., Passos, C.J.S., da Silva, E.D., de Andrade, P.S., Mergler, D., Guimaraes, J.R.D. and Amorim, M. | Effects of recent human colonization on the presence of mercury in Amazonian ecosystems | 1999 | Water Air and Soil Pollution Vol. 112(3-4), pp. 297-313 |
article | DOI URL |
Abstract: Three Hg sources were characterised and mass balance calculations were used to determine their relative contributions to the contamination of the Amazonian environment. About an order of magnitude more Hg is emitted to the atmosphere by goldmining activity than by the burning of forest biomass. However, anthropogenic atmospheric Hg cannot account for the high Hg burdens found in terrestrial ecosystems: deposition of Hg from goldmining sources is estimated to account for less than 3% of the Hg present in the surface horizons of soils. We propose that erosion of deforested soils following human colonization constitutes a major disturbance of the natural Hg cycle. Deforestation thus increases soil Hg mobilisation by runoff, which may explain the increase of Hg burdens in Amazonian aquatic ecosystems in newly colonized watersheds. | |||||
BibTeX:
@article{roulet_effects_1999, author = {Roulet, M. and Lucotte, M. and Farella, N. and Serique, G. and Coelho, H. and Passos, C. J. S. and da Silva, E. D. and de Andrade, P. S. and Mergler, D. and Guimaraes, J. R. D. and Amorim, M.}, title = {Effects of recent human colonization on the presence of mercury in Amazonian ecosystems}, journal = {Water Air and Soil Pollution}, year = {1999}, volume = {112}, number = {3-4}, pages = {297--313}, url = {://WOS:000080721900007}, doi = {https://doi.org/10.1023/a:1005073432015} } |
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Roulet, M., Lucotte, M., Canuel, R., Farella, N., Goch, Y.G.D., Peleja, J.R.P., Guimaraes, J.R.D., Mergler, D. and Amorim, M. | Spatio-temporal geochemistry of mercury in waters of the Tapajos and Amazon rivers, Brazil | 2001 | Limnology and Oceanography Vol. 46(5), pp. 1141-1157 |
article | URL |
Abstract: Spatial and temporal variations of mercury (HE) concentrations were monitored in the surface waters from the lower portion of the Tapajos River, the Arapiuns River, its principal tributary, and the Amazon River at its confluence with the Tapajos, In the rivers, Hg concentrations in the water column are governed by the concentration of suspended particles. tig in the filtered water showed very little seasonal variation with low concentrations in the lower Tapajos (textless1.8 ng L-1), Arapiuns (textless0.8 ng L-1), and Amazon (textless2.8 ng L-1). Concentrations of fine particulate Hg (0.6-29.7 ng L-1) represent 40%-90% of the total volumetric concentration of Hg. In relation to their oxyhydroxide contents, suspended particles are not richer in Hg than nearby soils where oxyhydroxides control the accumulation of Hg. The study shows that the dominant stock of Hg in the aquatic ecosystems of this region is derived from erosion of natural soils in the catchment rather than from anthropogenic pollution. The input of natural Hg coming from soils into the aquatic ecosystems may have increased over historical levels in the region. This increase of total tig in aquatic ecosystems could potentially account for high levels of methylmercury recently reported in fish and humans in the lower Tapajos River area, but the link between the different processes that promote high levels of methylmercury exposure for the human community remains to be proved. | |||||
BibTeX:
@article{roulet_spatio-temporal_2001, author = {Roulet, M. and Lucotte, M. and Canuel, R. and Farella, N. and Goch, Y. G. D. and Peleja, J. R. P. and Guimaraes, J. R. D. and Mergler, D. and Amorim, M.}, title = {Spatio-temporal geochemistry of mercury in waters of the Tapajos and Amazon rivers, Brazil}, journal = {Limnology and Oceanography}, year = {2001}, volume = {46}, number = {5}, pages = {1141--1157}, url = {://WOS:000169913700014} } |
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Roulet, M., Lucotte, M., Canuel, R., Farella, N., Courcelles, M., Guimaraes, J.R.D., Mergler, D. and Amorim, M. | Increase in mercury contamination recorded in lacustrine sediments following deforestation in the central Amazon | 2000 | Chemical Geology Vol. 165(3-4), pp. 243-266 |
article | DOI URL |
Abstract: The geochemical study of surface sediments (vertical profiles of 30-80 cm) from lentic ecosystems of the Tapajos River permit the observation of environmental changes responsible for the mercury contamination of aquatic systems exploited by the human riverine population. The Arapiuns and Amazon rivers are compared. Measurements of mercury, textural indicators (water content and dry density), mineralogic indicators (iron and aluminum associated with oxyhydroxides and aluminosilicates), and organic indicators (carbon, nitrogen, atomic C/N ratio) were performed over the full length of the cores. The results demonstrate that soil erosion is responsible for an increase in surficial sediment mercury concentrations in the different aquatic systems of the Tapajos and Arapiuns rivers. This increase is the result of the relative enrichment of the sedimentary deposits in fine particulates rich in aluminosilicates, oxyhydroxides and mercury, transported in suspension in the water column. The oxyhydroxides of iron and aluminum associated with fine, clayey particles seem to control the accumulation of heavy metals in the sediments of the Tapajos, Arapiuns and Amazon rivers. Overall, the mercury levels in the sediments studied have the same relationship with the aluminosilicates and the texture of the sediments. The quantity of aluminosilicates permits the evaluation of diagenetic effects, the influence of the clay content and the matrix effect on the levels of mercury in sediments. The activity of lead-210 measured in two cores suggests that the superficial sediments originate from eroded soils. A preliminary dating using the constant initial concentration model indicates that the environmental changes recorded in the Tapajos River sediments would have been initiated some time between the 1950s and 1970s. They would then coincide with the important colonization of the Brazilian Amazon during this period. The results presented have important implications for the geochemical interpretation of anthropogenic disturbances in the Amazon. They demonstrate that the recent colonization of the drainage basins and the growing exploitation of new parcels of land in the central Amazon disturb the mineral and organic matter cycles, as well as that of mercury. The ensuing result is increased exportation of fine particulate mercury from the surface of soils to drainage waters that transport them to fluvio-lacustrine systems where they finally settle out. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{roulet_increase_2000, author = {Roulet, M. and Lucotte, M. and Canuel, R. and Farella, N. and Courcelles, M. and Guimaraes, J. R. D. and Mergler, D. and Amorim, M.}, title = {Increase in mercury contamination recorded in lacustrine sediments following deforestation in the central Amazon}, journal = {Chemical Geology}, year = {2000}, volume = {165}, number = {3-4}, pages = {243--266}, url = {://WOS:000086004000005}, doi = {https://doi.org/10.1016/s0009-2541(99)00172-2} } |
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Roulet, M. and Lucotte, M. | Characterization of pesticide consumption of the municipality of Santarém, Brazilian Amazon [BibTeX] |
2001 | Acta Amazonica Vol. 30, pp. 615-628 |
article | |
BibTeX:
@article{roulet_characterization_2001, author = {Roulet, M. and Lucotte, M.}, title = {Characterization of pesticide consumption of the municipality of Santarém, Brazilian Amazon}, journal = {Acta Amazonica}, year = {2001}, volume = {30}, pages = {615--628} } |
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Roulet, M., Guimaraes, J.R.D. and Lucotte, M. | Methylmercury production and accumulation in sediments and soils of an amazonian floodplain - Effect of seasonal inundation | 2001 | Water Air and Soil Pollution Vol. 128(1-2), pp. 41-60 |
article | DOI URL |
Abstract: This study investigated the spatial and seasonal variations of MeHg concentrations and burdens of different sediments and soils of the Tapajos river floodplain, one of the major clear-water tributaries of the Amazon. The small floodplain of the Tapajos is typical of Amazonian floodplain ecosystems. The studied lakes are bordered by inundated forest (igapo), while floating macrophyte mats (Paspalum sp.) develop at the margin of lakes during the flooded season. During the flood, we observed very low MeHg concentrations in the open water lake sediments (textless0.5 ng g(-1) d.w or textless0.5 mug m(-2) cm(-1) d.w.) as compared to the semi-aquatic sediments of the macrophyte zone (0.2-1.4 ng g(-1) d.w or 1-3 mug m(-2) cm(-1) d.w.) and the igapo semi-terrestrial soils (0.2-3 ng g(-1) d.w or 2-12 mug m(-2) cm(-1) d.w.). The litter horizon from the igapo soils showed the highest value of MeHg (4-8 ng g(-1) d.w.) representing 0.2-2 mug m(-2) cm(-1) d.w. at the sediment/water interface during the aquatic phase. The inundation had no effect on the concentrations and burdens of MeHg in the sediment of the central part of the lake. The inundation had a clear effect on the methylation of Hg at the surface of semi-aquatic shoreline sediments (macrophyte zone) and semi-terrestrial forest soils, where MeHg concentrations and burdens appeared to be 3 times greater following inundation. In all cores, total Hg concentrations follow those of Fe and Al oxy-hydroxides, whereas the MeHg concentrations are linked to organic matter quality and quantity. It is suggested that organic matter and inundation control MeHg production and accumulation at the benthic interface. These results confirm previous observations, in the same study area, of net Hg-203 methylation potentials. The fresh and labile organic matter in the litter of the igapo forest appears as the most important factor leading to significant enrichment of MeHg in these particular terrestrial/aquatic sedimentary environments. | |||||
BibTeX:
@article{roulet_methylmercury_2001, author = {Roulet, M. and Guimaraes, J. R. D. and Lucotte, M.}, title = {Methylmercury production and accumulation in sediments and soils of an amazonian floodplain - Effect of seasonal inundation}, journal = {Water Air and Soil Pollution}, year = {2001}, volume = {128}, number = {1-2}, pages = {41--60}, url = {://WOS:000167945300004}, doi = {https://doi.org/10.1023/a:1010379103335} } |
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Rottenberger, S., Kuhn, U., Wolf, A., Schebeske, G., Oliva, S.T., Tavares, T.M. and Kesselmeier, J. | Formaldehyde and acetaldehyde exchange during leaf development of the Amazonian deciduous tree species Hymenaea courbaril | 2005 | Atmospheric Environment Vol. 39(12), pp. 2275-2279 |
article | DOI URL |
Abstract: The effect of leaf age on the formaldehyde (HCHO) and acetaldehyde (CH3CHO) exchange pattern of the deciduous Amazonian tree species Hymenaea courbaril was investigated under field conditions. Branch enclosure measurements on senescent, young, and mature leaves showed that leaf development had a pronounced impact on the aldehyde exchange behavior with respect to both the direction and the magnitude of the exchange. The emission activity of senescent leaves was associated with a negative CO2 balance, even during daytime, indicative of a catabolic metabolism and decomposition processes leading to an increased aldehyde production within the leaf. The low exchange rates observed in young leaves were attributed to low stomatal conductance, while in mature leaves stomatal conductance and metabolic activities allowed efficient uptake. Within each leaf class the diurnal variations in the exchange of both aldehyde compounds were found to be mainly dependent on the respective ambient air concentrations. High ambient air concentrations resulted in decreased emission rates of senescent leaves and in enhanced uptake in young and mature leaves. CH3CHO compensation points decreased from 1.8 to 1.1 ppb with leaf maturation. We provide evidence that leaf-age-dependent variations in the stomatal conductance can account for the major share of differences in the CH3CHO deposition velocity. The results indicate that leaf surfaces of young and mature leaves may represent an effective additional non-stomatal sink for atmospheric aldehydes. © 2005 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{rottenberger_formaldehyde_2005, author = {Rottenberger, S. and Kuhn, U. and Wolf, A. and Schebeske, G. and Oliva, S. T. and Tavares, T. M. and Kesselmeier, J.}, title = {Formaldehyde and acetaldehyde exchange during leaf development of the Amazonian deciduous tree species Hymenaea courbaril}, journal = {Atmospheric Environment}, year = {2005}, volume = {39}, number = {12}, pages = {2275--2279}, url = {://WOS:000228945400011}, doi = {https://doi.org/10.1016/j.atmosenv.2004.12.027} } |
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Rottenberger, S., Kuhn, U., Wolf, A., Schebeske, G., Oliva, S.T., Tavares, T.M. and Kesselmeier, J. | Exchange of short-chain aldehydes between Amazonian vegetation and the atmosphere | 2004 | Ecological Applications Vol. 14(4), pp. S247-S262 |
article | URL |
Abstract: As a part of the LBA-EUSTACH (EUropean Studies on Trace Gases and Atmospheric CHemistry as a contribution of the Large-scale Biosphere-Atmosphere experiment in Amazonia) project, the exchanges of formaldehyde (HCHO) and acetaldehyde (CH3CHO) between Amazonian vegetation and the atmosphere were investigated by branch enclosures and compared with gradient measurements during the wet-to-dry transition and dry-to-wet-transition periods at a remote forest site in Brazil, 1999. Branch enclosure measurements of several tree species showed emission as well as deposition of short-chain aldehydes, but fluxes were clearly dominated by deposition during both seasons. This bidirectional exchange was found to depend mainly on the actual ambient concentrations of these compounds and to exhibit a compensation point below 0.6 ppb of the compound in air with deposition velocities between 0.16 and 0.21 cm/s during the wet-to-dry season. During the dry-to-wet season, the deposition velocities and the compensation point increased. Under the clean air conditions of the wet-to-dry season, the major pathway for the aldehyde uptake was via leaf stomata. For HCHO, a mesophyll resistance of the same order of magnitude as the stomatal resistance contributed to the total leaf surface resistance, whereas the mesophyll resistance for CH3CHO was small, allowing a rapid uptake. This finding indicates a major contribution of metabolic consumption processes in addition to physical and chemical processes to the overall resistance. During the dry-to-wet period, when ambient air concentrations substantially increased, we found indications for an additional deposition to the leaf cuticle. Vertical gradient measurements of ambient air concentrations in and above the canopy closely agreed with the branch enclosure studies and confirmed that the forest acts rather as a sink than as a direct source for HCHO and CH3CHO. Diel courses of ambient air concentrations and ratios of HCHO and CH3CHO above the canopy suggest photochemical oxidation of biogenically or pyrogenically emitted precursor compounds as the major sources for short-chain aldehydes in the tropical atmosphere. | |||||
BibTeX:
@article{rottenberger_exchange_2004, author = {Rottenberger, S. and Kuhn, U. and Wolf, A. and Schebeske, G. and Oliva, S. T. and Tavares, T. M. and Kesselmeier, J.}, title = {Exchange of short-chain aldehydes between Amazonian vegetation and the atmosphere}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S247--S262}, url = {://WOS:000223269000021} } |
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Rottenberger, S., Kleiss, B., Kuhn, U., Wolf, A., Piedade, M.T.F., Junk, W. and Kesselmeier, J. | The effect of flooding on the exchange of the volatile C-2-compounds ethanol, acetaldehyde and acetic acid between leaves of Amazonian floodplain tree species and the atmosphere | 2008 | Biogeosciences Vol. 5(4), pp. 1085-1100 |
article | URL |
Abstract: The effect of root inundation on the leaf emissions of ethanol, acetaldehyde and acetic acid in relation to assimilation and transpiration was investigated with 2-3 years old tree seedlings of four Amazonian floodplain species by applying dynamic cuvette systems under greenhouse conditions. Emissions were monitored over a period of several days of inundation using a combination of Proton Transfer Reaction Mass Spectrometry (PTR-MS) and conventional techniques (HPLC, ion chromatography). Under non-flooded conditions, none of the species exhibited measurable emissions of any of the compounds, but rather low deposition of acetaldehyde and acetic acid was observed instead. Tree species specific variations in deposition velocities were largely due to variations in stomatal conductance. Flooding of the roots resulted in leaf emissions of ethanol and acetaldehyde by all species, while emissions of acetic acid were only observed from the species exhibiting the highest ethanol and acetaldehyde emission rates. All three compounds showed a similar diurnal emission profile, each displaying an emission burst in the morning, followed by a decline in the evening. This concurrent behavior supports the conclusion, that all three compounds emitted by the leaves are derived from ethanol produced in the roots by alcoholic fermentation, transported to the leaves with the transpiration stream and finally partly converted to acetaldehyde and acetic acid by enzymatic processes. Co-emissions and peaking in the early morning suggest that root ethanol, after transportation with the transpiration stream to the leaves and enzymatic oxidation to acetaldehyde and acetate, is the metabolic precursor for all compounds emitted, though we can not totally exclude other production pathways. Emission rates substantially varied among tree species, with maxima differing by up to two orders of magnitude (25-1700 nmol m(-2) min(-1) for ethanol and 5-500 nmol m(-2) min(-1) for acetaldehyde). Acetic acid emissions reached 12 nmol m(-2) min(-1). The observed differences in emission rates between the tree species are discussed with respect to their root adaptive strategies to tolerate long term flooding, providing an indirect line of evidence that the root ethanol production is a major factor determining the foliar emissions. Species which develop morphological root structures allowing for enhanced root aeration produced less ethanol and showed much lower emissions compared to species which lack gas transporting systems, and respond to flooding with substantially enhanced fermentation rates and a non-trivial loss of carbon to the atmosphere. The pronounced differences in the relative emissions of ethanol to acetaldehyde and acetic acid between the tree species indicate that not only the ethanol production in the roots but also the metabolic conversion in the leaf is an important factor determining the release of these compounds to the atmosphere. | |||||
BibTeX:
@article{rottenberger_effect_2008, author = {Rottenberger, S. and Kleiss, B. and Kuhn, U. and Wolf, A. and Piedade, M. T. F. and Junk, W. and Kesselmeier, J.}, title = {The effect of flooding on the exchange of the volatile C-2-compounds ethanol, acetaldehyde and acetic acid between leaves of Amazonian floodplain tree species and the atmosphere}, journal = {Biogeosciences}, year = {2008}, volume = {5}, number = {4}, pages = {1085--1100}, url = {://WOS:000259986400009} } |
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Rosolem, R., Shuttleworth, W.J., Zeng, X., Saleska, S.R. and Huxman, T.E. | Land surface modeling inside the Biosphere 2 tropical rain forest biome | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115 |
article | DOI URL |
Abstract: Tropical rain forests contribute substantially to regional and global energy, water, and carbon exchanges between the land surface and the atmosphere, and better understanding of the mechanisms of vegetation response to different environmental stresses is needed. The Biosphere 2 facility provides an opportunity to link laboratory-scale and plot-scale studies in a controllable environment. We compiled a consistent quality-controlled time series of climate data from Biosphere 2 and used it to drive the Simple Biosphere model (SiB3) to test how well it represented the behavior of soils and vegetation inside the tropical rain forest biome of Biosphere 2 (B2-TRF). We found that soil respiration parameterization in SiB3 was not suitable for use in B2-TRF, so several alternative parameterizations were tested. None gave outstanding results, but a modified version of the parameterization originally proposed for SiB3 gave the best results. With this modification, SiB3 well simulated the observed net ecosystem exchange in B2-TRF but, significantly, only after additionally modifying parameters describing the thermal tolerance of plants so that photosynthetic capacity was reduced on average but maintained to higher temperatures. This implies either that tropical rain forest species can acclimate to higher temperatures than allowed for by vegetation models or that the plant community assembly in B2-TRF has shifted to allow continued functioning at higher temperatures, and plants in natural ecosystems could also. In either case, this suggests that the Amazon rain forest may be more resilient to climate change than hitherto thought. | |||||
BibTeX:
@article{rosolem_land_2010, author = {Rosolem, Rafael and Shuttleworth, W. James and Zeng, Xubin and Saleska, Scott R. and Huxman, Travis E.}, title = {Land surface modeling inside the Biosphere 2 tropical rain forest biome}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, url = {://WOS:000285463600001}, doi = {https://doi.org/10.1029/2010jg001443} } |
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Rosolem, R., Shuttleworth, W.J. and de Gonçalves, L.G.G. | Is the data collection period of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia representative of long-term climatology? | 2008 | Journal of Geophysical Research Vol. 113 |
article | DOI URL |
Abstract: The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) sampled surface-atmosphere flux exchanges and related ecohydrometeorological processes at several flux tower sites in the Amazonian region between 1999 and 2006. This extensive database is now being analyzed to investigate, for example, the carbon balance of the Amazon basin and the effect of land use change in the basin on climate. It is therefore important to establish whether the period during which these data were collected is representative of the long-term climatology for the region. This study analyzed long-term climate station data for stations located nearby the LBA eddy flux tower sites. Measurements taken during the period of data collection were compared with the long-term station climatology using the Kolmogorov-Smirnov test and analysis of histogram from random samples from the long-term climatological record. In terms of precipitation, the LBA data collection period is statistically consistent with the climatology for all LBA study sites. In terms of temperature, the same result is true for most flux station sites; the main exception being the Bananal Island site where the temperature during the LBA period is significantly warmer by about 1 degrees C. There were some short periods when temperature in the region of other LBA flux sites was also statistically different ( higher) during the LBA data collection period and an average but not statistically significant tendency toward higher temperatures across the whole region during the LBA period relative to previous years. This is probably because there has been significant land cover change near some of the LBA study sites, but a contribution from climate warming cannot be ruled out. | |||||
BibTeX:
@article{rosolem_is_2008, author = {Rosolem, Rafael and Shuttleworth, William James and de Gonçalves, Luis Gustavo Gonçalves}, title = {Is the data collection period of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia representative of long-term climatology?}, journal = {Journal of Geophysical Research}, year = {2008}, volume = {113}, url = {://WOS:000261145100001}, doi = {https://doi.org/10.1029/2007jg000628} } |
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Rosolem, R., Gupta, H.V., Shuttleworth, W.J., Zeng, X. and Gonçalves, L.G.G.d. | A fully multiple-criteria implementation of the Sobol’ method for parameter sensitivity analysis [BibTeX] |
2012 | Journal of Geophysical Research Vol. 117(D07103), pp. doi:10.1029/2011JD016355 |
article | |
BibTeX:
@article{rosolem_fully_2012, author = {Rosolem, R. and Gupta, H. V. and Shuttleworth, W. J. and Zeng, X. and Gonçalves, L. G. G. de}, title = {A fully multiple-criteria implementation of the Sobol’ method for parameter sensitivity analysis}, journal = {Journal of Geophysical Research}, year = {2012}, volume = {117}, number = {D07103}, pages = {doi:10.1029/2011JD016355} } |
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Rosolem, R., Gupta, H.V., Shuttleworth, W.J., Gonçalves, L.G.G.d. and Zeng, X. | Towards a comprehensive approach to parameter estimation in land surface parameterization schemes [BibTeX] |
2012 | Hydrological Processes Vol. http://onlinelibrary.wiley.com/doi/10.1002/hyp.9362/abstract |
article | DOI |
BibTeX:
@article{rosolem_towards_2012, author = {Rosolem, R. and Gupta, H. V. and Shuttleworth, W. J. and Gonçalves, L. G. G. de and Zeng, X.}, title = {Towards a comprehensive approach to parameter estimation in land surface parameterization schemes}, journal = {Hydrological Processes}, year = {2012}, volume = {http://onlinelibrary.wiley.com/doi/10.1002/hyp.9362/abstract}, doi = {https://doi.org/10.1002/hyp.9362} } |
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Rosenqvist, A., Shimada, M., Chapman, B., Freeman, A., De Grandi, G., Saatchi, S. and Rauste, Y. | The Global Rain Forest Mapping project - a review | 2000 | International Journal of Remote Sensing Vol. 21(6-7), pp. 1375-1387 |
article | DOI URL |
Abstract: The Global Rain Forest Mapping (GRFM) project is an international endeavour led by the National Space Development Agency of Japan (NASDA), with the aim of producing spatially and temporally contiguous Synthetic Aperture Radar (SAR) data sets over the tropical belt on the Earth by use of the JERS-1 L-band SAR, through the generation of semi-continental, 100 m resolution, image mosaics. The GRFM project relies on extensive collaboration with the National Aeronautics and Space Administration (NASA), the Joint Research Centre of the European Commission (JRC) and the Japanese Ministry of International Trade and Industry (MITI) for data acquisition, processing, validation and product generation. A science programme is underway in parallel with product generation. This involves the agencies mentioned above, as well as a large number of international organizations, universities and individuals to perform field activities and data analysis at different levels. The GRFM project was initiated in 1995 and, through a dedicated data acquisition policy by NASDA, data acquisitions could be completed within a 1.5-year period, resulting in a spatially and temporally homogeneous coverage to encompass the entire Amazon Basin from the Atlantic to the Pacific; Central America up to the Yucatan Peninsular in Mexico; equatorial Africa from Madagascar and Kenya in the east to Sierra Leone in the west; and south-east Asia, including Papua New Guinea and northern Australia. Over the Amazon and Congo river basins, the project aimed to provide complete cover at two different seasons, featuring the basins at high and low water. In total, the GRFM acquisitions comprise some 13 000 SAR scenes, which are currently in the course of being processed and compiled into image mosaics. In March 1999, SAR mosaics over the Amazon Basin tone out of two seasonal coverages) and equatorial Africa (both seasonal coverages) were completed; the data are available on CD-ROM and, at a coarser resolution, via the Internet. Coverage of the second-season Amazon and Central America will be completed during 1999, with the south-east Asian data sets following thereafter. All data are being provided free of charge to the international science community for research and educational purposes. | |||||
BibTeX:
@article{rosenqvist_global_2000, author = {Rosenqvist, A. and Shimada, M. and Chapman, B. and Freeman, A. and De Grandi, G. and Saatchi, S. and Rauste, Y.}, title = {The Global Rain Forest Mapping project - a review}, journal = {International Journal of Remote Sensing}, year = {2000}, volume = {21}, number = {6-7}, pages = {1375--1387}, url = {://WOS:000086357700015}, doi = {https://doi.org/10.1080/014311600210227} } |
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Rosenqvist, A., Forsberg, B.R., Pimentel, T., Rauste, Y.A. and Richey, J.E. | The use of spaceborne radar data to model inundation patterns and trace gas emissions in the central Amazon floodplain | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1303-1328 |
article | DOI URL |
Abstract: River floodplains are the dominant wetland habitat in the Amazon river basin, providing important habitation for aquatic ? ora and fauna, and playing a key role in sustaining regional fish production. The annual inundation pulse has been identified as the dominant environmental factor affecting aquatic biota on the floodplain, and the characteristics of this pulse, in terms of timing, duration and amplitude, vary spatially on the floodplain as a function of fluctuations in river stage height and topography. River floodplains are furthermore globally significant sources of methane (CH4) and other trace gases essential to climate regulation. Refined information on wetland distributions and dynamics are currently needed to improve estimates of habitat availability and to calculate regional contributions of trace gases, especially CH4, to the troposphere. This paper describes how multitemporal time series of spaceborne L-band Synthetic Aperture Radar (SAR) data from the Japanese Earth Resource Satellite 1 ( JERS-1) were used to generate a model of the spatial and temporal variation of inundation on the floodplain of a typical black water river in the Central Brazilian Amazon and how this model was utilized, together with in situ measurements of river stage heights and CH4 fluxes, to model regional estimates of CH4 emissions. We also demonstrate how a JERS-1 SAR time series can be used to map the spatial variation of flood duration on the floodplain, a key factor controlling local variations in plant biodiversity. For both applications, the availability of adequate time series of satellite sensor data is the prime factor affecting the reliability and accuracy of the flood models and the spatial details of the flood duration map. The availability of in situ data, especially daily river height measurements, was also critical for the development of the flooding model and for the subsequent decoupling of the model from the satellite sensor data. | |||||
BibTeX:
@article{rosenqvist_use_2002, author = {Rosenqvist, A. and Forsberg, B. R. and Pimentel, T. and Rauste, Y. A. and Richey, J. E.}, title = {The use of spaceborne radar data to model inundation patterns and trace gas emissions in the central Amazon floodplain}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1303--1328}, url = {://WOS:000174661900007}, doi = {https://doi.org/10.1080/01430060110092911} } |
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Rosenfeld, D., Zheng, Y., Hashimshoni, E., Pöhlker, M.L., Jefferson, A., Pöhlker, C., Yuh, X., Zhud, Y., Liuh, G., Yueh, Z., Fischman, B., Li, Z., Giguzin, D., Gorena, T., Artaxo, P., Barbosa, H.M.J., Pöschl, U. and Andreae, M.O. | Satellite retrieval of cloud condensation nuclei concentrations by using clouds as CCN chambers [BibTeX] |
2016 | Proceedings of the National Academy of Sciences of the United States of America | article | |
BibTeX:
@article{rosenfeld_satellite_2016, author = {Rosenfeld, Daniel and Zheng, Youtong and Hashimshoni, Eyal and Pöhlker, Mira L. and Jefferson, Anne and Pöhlker, Christopher and Yuh, Xing and Zhud, Yannian and Liuh, Guihua and Yueh, Zhiguo and Fischman, Baruch and Li, Zhanqing and Giguzin, David and Gorena, Tom and Artaxo, Paulo and Barbosa, Henrique M. J. and Pöschl, Ulrich and Andreae, Meinrat O.}, title = {Satellite retrieval of cloud condensation nuclei concentrations by using clouds as CCN chambers}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2016} } |
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Rosario, N.E., Yamasoe, M.A. and Longo, K.M. | Aerosol Optical Depth and Angstrom Coefficient retrievals over the Amazon Forest during 2007 biomass burning season | 2009 | Vol. 1100Current Problems in Atmospheric Radiation, pp. 494-497 |
incollection | URL |
Abstract: An intensive measurement campaign aiming to study Photosynthetically Active Radiation profiles inside the canopy at the Amazon Forest took place during 2007 biomass burning season, from 22 August to 30 October. During this period, aerosol optical properties were monitored using distinct radiometers: a Multi-Filter Rotating Shadowband Radiometer (MFRSR), the AERONET sunphotometer, a handheld Microtops sunphotometer and Moderate Imaging Spectrometer (MODIS) aboard Terra and Aqua satellites. The Aerosol Optical Depth (AOD) varied strongly during the campaign with the daily average at 670 nm reaching values from 0.5 to 3.0. Angstrom coefficient (a) calculated with AOD at 670 and 870 nm increase from 1.5, before the burning season, to 2.0 as a result of an increase of fine particles into the atmosphere. In early October, the AOD decreased and, as a consequence of the increasing frequency of rain events, AOD went back to the levels observed before burning season. Despite the fact that the distance of AERONET sunphotometer from the experimental site was 80 km, the retrievals obtained from all ground-based radiometers were consistent and showed good agreement. On the other hand, MODIS retrievals overestimated the AOD during high aerosol concentration when compared with ground-based radiometers. | |||||
BibTeX:
@incollection{nakajima_aerosol_2009, author = {Rosario, Nilton E. and Yamasoe, Marcia A. and Longo, Karla M.}, title = {Aerosol Optical Depth and Angstrom Coefficient retrievals over the Amazon Forest during 2007 biomass burning season}, booktitle = {Current Problems in Atmospheric Radiation}, year = {2009}, volume = {1100}, pages = {494--497}, url = {://WOS:000265672300121} } |
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Rosario, N.E., Yamasoe, M.A., Brindley, H., Eck, T.F. and Schafer, J. | Downwelling solar irradiance in the biomass burning region of the southern Amazon: Dependence on aerosol intensive optical properties and role of water vapor | 2011 | Journal of Geophysical Research-Atmospheres Vol. 116 |
article | DOI URL |
Abstract: The sensitivity of solar irradiance at the surface to the variability of aerosol intensive optical properties is investigated for a site (Alta Floresta) in the southern portion of the Amazon basin using detailed comparisons between measured and modeled irradiances. Apart from aerosol intensive optical properties, specifically single scattering albedo (omega(o lambda)) and asymmetry parameter (g(lambda)), which were assumed constant, all other relevant input to the model were prescribed based on observation. For clean conditions, the differences between observed and modeled irradiances were consistent with instrumental uncertainty. For polluted conditions, the agreement was significantly worse, with a root mean square difference three times larger (23.5 Wm(-2)). Analysis revealed a noteworthy correlation between the irradiance differences (observed minus modeled) and the column water vapor (CWV) for polluted conditions. Positive differences occurred mostly in wet conditions, while the differences became more negative as the atmosphere dried. To explore the hypothesis that the irradiance differences might be linked to the modulation of omega(o lambda) and g(lambda) by humidity, AERONET retrievals of aerosol properties and CWV over the same site were analyzed. The results highlight the potential role of humidity in modifying omega(o lambda) and g(lambda) and suggest that to explain the relationship seen between irradiances differences via aerosols properties the focus has to be on humidity-dependent processes that affect particles chemical composition. Undoubtedly, there is a need to better understand the role of humidity in modifying the properties of smoke aerosols in the southern portion of the Amazon basin. | |||||
BibTeX:
@article{rosario_downwelling_2011, author = {Rosario, Nilton E. and Yamasoe, Marcia A. and Brindley, Helen and Eck, Thomas F. and Schafer, Joel}, title = {Downwelling solar irradiance in the biomass burning region of the southern Amazon: Dependence on aerosol intensive optical properties and role of water vapor}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2011}, volume = {116}, url = {://WOS:000295267600004}, doi = {https://doi.org/10.1029/2011jd015956} } |
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Rosário, N.E., Sauini, T., Pauliquevis, T., Barbosa, H.M.J., Yamasoe, M.A. and Barja, B. | Aerosol optical depth retrievals in central Amazonia from a multi-filter rotating shadow-band radiometer calibrated on-site [BibTeX] |
2019 | Atmos. Meas. Tech. Vol. 12(2), pp. 921-934 |
article | DOI URL |
BibTeX:
@article{rosario_aerosol_2019, author = {Rosário, N. E. and Sauini, T. and Pauliquevis, T. and Barbosa, H. M. J. and Yamasoe, M. A. and Barja, B.}, title = {Aerosol optical depth retrievals in central Amazonia from a multi-filter rotating shadow-band radiometer calibrated on-site}, journal = {Atmos. Meas. Tech.}, year = {2019}, volume = {12}, number = {2}, pages = {921--934}, url = {https://amt.copernicus.org/articles/12/921/2019/}, doi = {https://doi.org/10.5194/amt-12-921-2019} } |
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Rosa, A.M., Ignotti, E., Hacon, S.d.S. and de Castro, H.A. | Prevalence of asthma in children and adolescents in a city in the Brazilian Amazon region | 2009 | Jornal Brasileiro De Pneumologia Vol. 35(1), pp. 7-13 |
article | URL |
Abstract: Objective: To analyze the prevalence of asthma and asthma symptoms in students of two distinct age brackets residing in the city of Tangara da Serra, Brazil. Methods: Cross-sectional, population-based study of the prevalence of asthma in children from 6 to 7 years of age and adolescents from 13 to 14, using the standardized International Study of Asthma and Allergies in Childhood, phase 1 questionnaire, validated for use in Brazil. Students who responded affirmatively to question 2 (presence of wheezing in the preceding 12 months) were classified as suffering from asthma. Results: The study comprised 3,362 students, of whom 1,634 (48.6%) were children and 1,728 (51.4%) were adolescents. Of the 1,634 children, 816 (49.9%) were male, and 818 (50.1%) were female. Of the 1,728 adolescents, 773 (45.0%) were male, and 955 (55.0%) were female. The prevalence of asthma among the children was 25.2%, whereas that among the adolescents was 15.9% (chi(2) = 8.34; p = 0.00). The children presented higher prevalences of the following symptoms of asthma than did the adolescents: wheezing ever (54.3%), nocturnal dry cough (43.9%), wheezing in the preceding 12 months (25.2%), and from I to 3 attacks of wheezing in the preceding 12 months (19.1%). There were no differences between the two groups regarding physician-diagnosed asthma (approximately 4.5%). There were no statistical differences regarding the prevalence of asthma by gender in the two groups. Conclusions: Tangara da Serra has a high prevalence of asthma in children and adolescents, and this result is compatible with other studies carried out in Brazil and Latin America using the same methodology. | |||||
BibTeX:
@article{rosa_prevalence_2009, author = {Rosa, Antonia Maria and Ignotti, Eliane and Hacon, Sandra de Souza and de Castro, Hermano Albuquerque}, title = {Prevalence of asthma in children and adolescents in a city in the Brazilian Amazon region}, journal = {Jornal Brasileiro De Pneumologia}, year = {2009}, volume = {35}, number = {1}, pages = {7--13}, note = {Edition: 2009/02/17}, url = {://WOS:000268917200002} } |
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Ronchail, J. and Gallaire, R. | Enso and rainfall along the Zongo valley (Bolivia) from the Altiplano to the Amazon basin | 2006 | International Journal of Climatology Vol. 26(9), pp. 1223-1236 |
article | DOI URL |
Abstract: The location of eight rainfall stations in the Zongo valley (Eastern Cordillera - Bolivia) between 1195 and 4750 meters above sea level (masl) gives a unique opportunity to study the time-space rainfall variability between two regions, i.e. the Altiplano and the Amazonian lowlands of Bolivia, that are differently related to El Nino-Southern Oscillation (ENSO) events in the Pacific. In the central part of the lowlands, a La Nina/dry signal is observed during the peak of the rainy season (February) and around wintertime (May and September). Going toward the Andes and on the foothills up to 1500 masl, no ENSO signal has been found. On the median slopes of the Zongo valley, between 1800 and 3500 m, a strong Nino/dry signal is depicted on an annual timescale and during summer. In February, a Nina/wet signal is also significant. Going westward through the high Andes and the eastern Altiplano, this signal weakens. On the western edge of the Altiplano, an El Nino/dry and La Nina/wet signals are clearly identified. In the central lowlands and on the western Altiplano, ENSO indexes account for nearly 25% of rainfall variability, and for as much as 50% along the median slopes of the eastern Cordillera, in the Zongo valley. This finding deserves further study as previous researches have shown that in the Andes the best relationship between rainfall and equatorial Pacific sea-surface temperature (SST) is in the western Altiplano, far from the Amazonian source of moisture. Copyright (C) 2006 Royal Meteorological Society. | |||||
BibTeX:
@article{ronchail_enso_2006, author = {Ronchail, Josyane and Gallaire, Robert}, title = {Enso and rainfall along the Zongo valley (Bolivia) from the Altiplano to the Amazon basin}, journal = {International Journal of Climatology}, year = {2006}, volume = {26}, number = {9}, pages = {1223--1236}, url = {://WOS:000239029600006}, doi = {https://doi.org/10.1002/joc.1296} } |
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Ronchail, J., Bourrel, L., Cochonneau, G., Vauchel, P., Phillips, L., Castro, A., Guyot, J.L. and de Oliveira, E. | Inundations in the Mamore basin (south-western Amazon-Bolivia) and sea-surface temperature in the Pacific and Atlantic Oceans | 2005 | Journal of Hydrology Vol. 302(1-4), pp. 223-238 |
article | DOI URL |
Abstract: Extensive inundations have been observed in the Llanos de Mojos (Mamore basin, south western Amazon) causing social and economic disasters. Since the beginning of the seventies precipitations have increased in the Bolivian lowlands (Llanos) and in the over-rainy eastern Cordillera and Andean foothills (Yungas) and inundations have become more frequent. As a result inundations have been investigated in relation to rainfall over the Mamore basin in Trinidad-Puerto Varador and, in order to determine whether they are predictable, in relation to Sea Surface Temperature (SST) in the Atlantic and the Equatorial Pacific Oceans. The methods are correlation and composite techniques. As expected, during the 1945-1946/1998-1999 period, inundations have been associated with abundant rainfall in the Mamore basin, mainly in the Llanos and Yungas. The role of rainfall in the inner dry Andes and downstream from Trinidad is more limited. When consecutive floods are observed, the ground water storage contributes to the occurrence of the second or third inundation event and rainfall anomaly is generally weaker. Rainfall in the Mamore basin is hardly associated with Sea Surface Temperature Anomalies (SSTA) in the Pacific and Atlantic Oceans during the 1952-1953/1998-1999 period. However, during the nineties the southern Atlantic SSTA account for 50 percent of rainfall variability. Inundations are also related to negative SSTA differences between the tropical and subtropical southern Atlantic. Two thirds of the 22 inundation events occurred in association with this oceanic anomaly that features a weak SSTA gradient in the southern Atlantic. During the 1988-1989/1998-1999 period, a particularly significant relation can be observed between SSTA and inundations events. Despite being associated with major El Nino events (1982-1983, 1991-1992), inundations are not significantly related to the equatorial Pacific SSTA. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{ronchail_inundations_2005, author = {Ronchail, J. and Bourrel, L. and Cochonneau, G. and Vauchel, P. and Phillips, L. and Castro, A. and Guyot, J. L. and de Oliveira, E.}, title = {Inundations in the Mamore basin (south-western Amazon-Bolivia) and sea-surface temperature in the Pacific and Atlantic Oceans}, journal = {Journal of Hydrology}, year = {2005}, volume = {302}, number = {1-4}, pages = {223--238}, url = {://WOS:000226396500014}, doi = {https://doi.org/10.1016/j.jhydrol.2004.07.005} } |
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Rommel da Silva, Leonardo Sá, Priscilla Barreto and Souza, W.d. | Estudo do nível da eficiência de uso da radiação em ecossistema florestal na Amazônia Oriental, durante o experimento COBRA-PARÁ [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 129-132 |
article | |
BibTeX:
@article{rommel_da_silva_estudo_2007, author = {Rommel da Silva and Leonardo Sá and Priscilla Barreto and Souza, Welbert de}, title = {Estudo do nível da eficiência de uso da radiação em ecossistema florestal na Amazônia Oriental, durante o experimento COBRA-PARÁ}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {129--132} } |
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Romero-Saltos, H., Sternberg, L., Moreira, M.Z. and Nepstad, D.C. | Rainfall exclusion in an eastern amazonian forest alters soil water movement and depth of water uptake | 2005 | American Journal of Botany Vol. 92(3), pp. 443-455 |
article | DOI URL |
Abstract: Deuterium-labeled water was used to study the effect of the Tapajos Throughfall Exclusion Experiment (TTEE) on soil moisture movement and on depth of water uptake by trees of Coussarea racemosa, Sclerolobium chrysophyllum, and Eschweilera pedicellata. The TTEE simulates an extended dry season in an eastern Amazonian rainforest, a plausible scenario if the El Nino phenomenon changes with climate change. The TTEE excludes 60% of the wet season throughfall from a 1-ha plot (treatment), while the control 1-ha plot receives precipitation year-round. Mean percolation rate of the label peak in the control plot was greater than in the treatment plot during the wet season (0.75 vs. 0.07 m/mo). The rate was similar for both plots during the dry season (ca. 0. 15 m/mo), indicative that both plots have similar topsoil structure. Interestingly, the label peak in the control plot during the dry season migrated upward an average distance of 64 cm. We show that water probably moved upward through soil pores-i.e., it did not involve roots (hydraulic lift)-most likely because of a favorable gradient of total (matric + gravitational) potential coupled with sufficient unsaturated hydraulic conductivity. Water probably also moved upward in the treatment plot, but was not detectable; the label in this plot did not percolate below 1 m or beyond the depth of plant water uptake. During the dry season, trees in the rainfall exclusion plot, regardless of species, consistently absorbed water significantly deeper, but never below 1.5-2 m, than trees in the control plot, and therefore may represent expected root function of this understory/subcanopy tree community during extended dry periods. | |||||
BibTeX:
@article{romero-saltos_rainfall_2005, author = {Romero-Saltos, H. and Sternberg, Ldsl and Moreira, M. Z. and Nepstad, D. C.}, title = {Rainfall exclusion in an eastern amazonian forest alters soil water movement and depth of water uptake}, journal = {American Journal of Botany}, year = {2005}, volume = {92}, number = {3}, pages = {443--455}, note = {Edition: 2005/03/01}, url = {://WOS:000227288500008}, doi = {https://doi.org/10.3732/ajb.92.3.443} } |
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Rogers, A., Medlyn, B., Dukes, J., Bonan, G., von Caemmerer, S., Dietze, M., Kattge, J., Leakey, A., Mercado, L., Niinemets, Ü., Prentice, I., Serbin, S., Sitch, S., Way, D. and Zaehle, S. | A Roadmap for Improving Representation of Photosynthesis in Earth System Models [BibTeX] |
2017 | New Phytologist Vol. 213(1), pp. 22-42 |
article | |
BibTeX:
@article{rogers_roadmap_2017, author = {Rogers, A. and Medlyn, B.E. and Dukes, J.S. and Bonan, G. and von Caemmerer, S. and Dietze, M.C. and Kattge, J. and Leakey, A.D.B. and Mercado, L.M. and Niinemets, Ü. and Prentice, I.C. and Serbin, S.P. and Sitch, S. and Way, D.A. and Zaehle, S.}, title = {A Roadmap for Improving Representation of Photosynthesis in Earth System Models}, journal = {New Phytologist}, year = {2017}, volume = {213}, number = {1}, pages = {22--42} } |
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Rodriguez, S., Tomasella, J., Demaria E., D. and Chou | Impacts of landscape fragmentation on simulated precipitation fields in the Amazonian sub-basin of Ji-Paraná using the Eta model [BibTeX] |
2014 | Theoretical and Applied Climatology Vol. 115, pp. 121-140 |
article | |
BibTeX:
@article{rodriguez_impacts_2014, author = {Rodriguez, S.C. ; Tomasella, J. ; Demaria, E., D.A. ; Chou}, title = {Impacts of landscape fragmentation on simulated precipitation fields in the Amazonian sub-basin of Ji-Paraná using the Eta model}, journal = {Theoretical and Applied Climatology}, year = {2014}, volume = {115}, pages = {121--140} } |
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Rodriguez, D.A., Tomasella, J. and Linhares, C. | Is the forest conversion to pasture affecting the hydrological response of Amazonian catchments? Signals in the Ji-Parana Basin | 2010 | Hydrological Processes Vol. 24(10), pp. 1254-1269 |
article | DOI URL |
Abstract: It is well known that land use and land-cover changes (LUCC), particularly deforestation, have the potential to modify the hydrological response. Although those signals are relatively well documented in worldwide microcatchment studies, conflicting results reported in literature indicate that those signals can be sometimes difficult to detect and isolate in basins at larger scales. In order to detect signals in the hydrological response potentially, related to LUCC, streamflow records from Ji-Parana Basin located in SW Amazonia are analysed in conjunction with deforestation maps derived from remote sensors. The basin has a drainage area greater than 30 000 km(2) and has been through severe LUCC in the last decades. Statistical descriptors of daily streamflow series were correlated with landscape indices using non-parametric methodologies. To take into account scale effects, statistical analyses were repeated in different sub-basins. Results showed that the impact of LUCC on the hydrological response is time lagged at larger scales. The flow paths are clearly affected, depending on basin characteristics such as topography. In general, LUCC impacts lead to higher peak streamflows, the reduction of minimal values and the increment of stormflow. In agreement with previous studies, the detection of signals associated with LUCC was clearly detected at the smallest basin, but proved to be difficult at larger scales, suggesting the existence of non-linear effects, which aggregate across scale compensating small scale effects. Such behaviour indicates a challenge for mathematical models, which are usually developed to represent immediate hydrological response to basin wide LUCC. Copyright (C) 2010 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{rodriguez_is_2010, author = {Rodriguez, Daniel Andres and Tomasella, Javier and Linhares, Claudia}, title = {Is the forest conversion to pasture affecting the hydrological response of Amazonian catchments? Signals in the Ji-Parana Basin}, journal = {Hydrological Processes}, year = {2010}, volume = {24}, number = {10}, pages = {1254--1269}, url = {://WOS:000277383500003}, doi = {https://doi.org/10.1002/hyp.7586} } |
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Rodrigues, T., Vourlitis, G.L., Lobo, F.d.A., Santanna, F.B., Arruda, P.H.d. and Nogueira, J.d.S. | Modeling canopy conductance under contrasting seasonal conditions for a tropical savanna ecosystem of south central Mato Grosso, Brazil [BibTeX] |
2016 | Agricultural and Forest Meteorology, pp. 218-219 | article | |
BibTeX:
@article{rodrigues_modeling_2016, author = {Rodrigues, T.R. and Vourlitis, G. L. and Lobo, F. de A. and Santanna, F. B. and Arruda, P. H.Z. de and Nogueira, J. de S.}, title = {Modeling canopy conductance under contrasting seasonal conditions for a tropical savanna ecosystem of south central Mato Grosso, Brazil}, journal = {Agricultural and Forest Meteorology}, year = {2016}, pages = {218--219} } |
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Rodrigues, T.R., Vourlitis, G.L., Lobo, F.d.A., Oliveira, R.G.d. and Nogueira, J.d.S. | Seasonal variation in energy balance and canopy conductance for a tropical savanna ecosystem of south central Mato Grosso, Brazil [BibTeX] |
2014 | JGR: Biogeosciences Vol. 119(1), pp. 1-13 |
article | |
BibTeX:
@article{rodrigues_seasonal_2014, author = {Rodrigues, Thiago R. and Vourlitis, George L. and Lobo, Francisco de A. and Oliveira, Renan G. de and Nogueira, José de S.}, title = {Seasonal variation in energy balance and canopy conductance for a tropical savanna ecosystem of south central Mato Grosso, Brazil}, journal = {JGR: Biogeosciences}, year = {2014}, volume = {119}, number = {1}, pages = {1--13} } |
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Rodrigues, T.B., Baker, C.R., Walker, A.P., McDowell, N., Rogers, A., Higuchi, N., Chambers, J.Q. and Jardine, K.J. | Stimulation of isoprene emissions and electron transport rates as key mechanisms of thermal tolerance in the tropical species Vismia guianensis | 2020 | Global Change Biology Vol. 26(10), pp. 5928-5941 |
article | DOI URL |
Abstract: Abstract Tropical forests absorb large amounts of atmospheric CO2 through photosynthesis, but high surface temperatures suppress this absorption while promoting isoprene emissions. While mechanistic isoprene emission models predict a tight coupling to photosynthetic electron transport (ETR) as a function of temperature, direct field observations of this phenomenon are lacking in the tropics and are necessary to assess the impact of a warming climate on global isoprene emissions. Here we demonstrate that in the early successional species Vismia guianensis in the central Amazon, ETR rates increased with temperature in concert with isoprene emissions, even as stomatal conductance (gs) and net photosynthetic carbon fixation (Pn) declined. We observed the highest temperatures of continually increasing isoprene emissions yet reported (50°C). While Pn showed an optimum value of 32.6 ± 0.4°C, isoprene emissions, ETR, and the oxidation state of PSII reaction centers (qL) increased with leaf temperature with strong linear correlations for ETR (ƿ = 0.98) and qL (ƿ = 0.99) with leaf isoprene emissions. In contrast, other photoprotective mechanisms, such as non-photochemical quenching, were not activated at elevated temperatures. Inhibition of isoprenoid biosynthesis repressed Pn at high temperatures through a mechanism that was independent of stomatal closure. While extreme warming will decrease gs and Pn in tropical species, our observations support a thermal tolerance mechanism where the maintenance of high photosynthetic capacity under extreme warming is assisted by the simultaneous stimulation of ETR and metabolic pathways that consume the direct products of ETR including photorespiration and the biosynthesis of thermoprotective isoprenoids. Our results confirm that models which link isoprene emissions to the rate of ETR hold true in tropical species and provide necessary “ground-truthing” for simulations of the large predicted increases in tropical isoprene emissions with climate warming. | |||||
BibTeX:
@article{rodrigues_stimulation_2020, author = {Rodrigues, Tayana B. and Baker, Christopher R. and Walker, Anthony P. and McDowell, Nate and Rogers, Alistair and Higuchi, Niro and Chambers, Jeffrey Q. and Jardine, Kolby J.}, title = {Stimulation of isoprene emissions and electron transport rates as key mechanisms of thermal tolerance in the tropical species Vismia guianensis}, journal = {Global Change Biology}, year = {2020}, volume = {26}, number = {10}, pages = {5928--5941}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.15213}, doi = {https://doi.org/10.1111/gcb.15213} } |
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Rodrigues, R.S., Barreto, P.N., Silva, R.B.C.d., Sá, L.D.A. and Nunes, H.G.C. | Variabilidade da direção do vento acima da Floresta Nacional de Caxiuanã, PA [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 133-136 |
article | |
BibTeX:
@article{rodrigues_variabilidade_2009, author = {Rodrigues, Ronaldo S. and Barreto, Priscilla N. and Silva, Rommel B. C. da and Sá, Leonardo D. A. and Nunes, Hildo G. C.}, title = {Variabilidade da direção do vento acima da Floresta Nacional de Caxiuanã, PA}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {133--136} } |
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Rodrigues, P., Silva, P., Ignotti, E., Rosa, A. and Hacon, S. | Spatial Distribution of Hospitalizations for Asthma in Elderly in the Brazilian Amazon [BibTeX] |
2011 | Epidemiology Vol. 22(1), pp. S166-S166 |
article | DOI URL |
BibTeX:
@article{rodrigues_spatial_2011, author = {Rodrigues, Poliany and Silva, Pamela and Ignotti, Eliane and Rosa, Antonia and Hacon, Sandra}, title = {Spatial Distribution of Hospitalizations for Asthma in Elderly in the Brazilian Amazon}, journal = {Epidemiology}, year = {2011}, volume = {22}, number = {1}, pages = {S166--S166}, url = {://WOS:000285400800492}, doi = {https://doi.org/10.1097/01.ede.0000392184.25124.9f} } |
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Rodrigues José Francisco de Carvalho, J.V.F.C. and Gonçalves | Leaf Gas Exchange, Photon Capture and Light Harvest in Aldina heterophylla along a Vegetation Gradient in the Amazon Rainforest [BibTeX] |
2014 | American Journal of Plant Sciences Vol. 05, pp. 1477-1488 |
article | |
BibTeX:
@article{rodrigues_leaf_2014, author = {Rodrigues, José Francisco de Carvalho, João Victor Figueiredo Cardoso; Gonçalves}, title = {Leaf Gas Exchange, Photon Capture and Light Harvest in Aldina heterophylla along a Vegetation Gradient in the Amazon Rainforest}, journal = {American Journal of Plant Sciences}, year = {2014}, volume = {05}, pages = {1477--1488} } |
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Rodrigues, J.C., Miranda, I.S. and Sousa, A.M.L.d. | Microclima em sub-bosque de pomar de mangueiras e de vegetação de área degradada na Amazônia Oriental [BibTeX] |
2018 | Revista Ambiente & Água Vol. 13(4) |
article | |
BibTeX:
@article{rodrigues_microclima_2018, author = {Rodrigues, Juliana Chagas and Miranda, Izildinha Souza and Sousa, Adriano Marlisom Leão de}, title = {Microclima em sub-bosque de pomar de mangueiras e de vegetação de área degradada na Amazônia Oriental}, journal = {Revista Ambiente & Água}, year = {2018}, volume = {13}, number = {4} } |
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Rodrigues, H., Costa, R., Ribeiro, J., Souza Filho, J., Ruivo, M. and Silva Júnior, J. | Variabilidade sazonal da condutância estomática em um ecossistema de manguezal amazônico e suas relações com variáveis meteorológicas [BibTeX] |
2011 | Revista Brasileira de Meteorologia Vol. 26(2), pp. 189 - 196 |
article | |
BibTeX:
@article{rodrigues_variabilidade_2011, author = {Rodrigues, H.J.B. and Costa, R.F. and Ribeiro, J.B.M. and Souza Filho, J.D.C. and Ruivo, M.L.P. and Silva Júnior, J.A.}, title = {Variabilidade sazonal da condutância estomática em um ecossistema de manguezal amazônico e suas relações com variáveis meteorológicas}, journal = {Revista Brasileira de Meteorologia}, year = {2011}, volume = {26}, number = {2}, pages = {189 -- 196} } |
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Rodrigues, A.V.P., Soares, N.T.D., Aguiar, R.G., Webler, A.D. and Castro, B.S. | Fluxo de Calor no Solo Modelado a Partir de Dados de Temperatura em Dois Níveis de Profundidade em uma Floresta Tropical na Amazônia Ocidental [BibTeX] |
2018 | Ciência e Natura Vol. 40, pp. 138-143 |
article | |
BibTeX:
@article{rodrigues_fluxo_2018, author = {Rodrigues, A. V. P. and Soares, N. T. D. and Aguiar, R. G. and Webler, A. D. and Castro, B. S.}, title = {Fluxo de Calor no Solo Modelado a Partir de Dados de Temperatura em Dois Níveis de Profundidade em uma Floresta Tropical na Amazônia Ocidental}, journal = {Ciência e Natura}, year = {2018}, volume = {40}, pages = {138--143} } |
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Rocha-Lima, J.V., Remer, L.A., Todd, M., Marsham, J.H., Engelstaedter, S., Ryder, C.L., Cavazos-Guerra, C., Artaxo, P., Colarco, P., Washington Richard, A. and Martins | A detailed characterization of the Saharan dust collected during the Fennec campaign in 2011: in situ ground-based and laboratory measurements [BibTeX] |
2018 | Atmospheric Chemistry And Physics Vol. 18, pp. 1023-1043 |
article | |
BibTeX:
@article{rocha-lima_detailed_2018, author = {Rocha-Lima, J. Vanderlei ; Remer, Lorraine A. ; Todd, Martin ; Marsham, John H. ; Engelstaedter, Sebastian ; Ryder, Claire L. ; Cavazos-Guerra, Carolina ; Artaxo, Paulo ; Colarco, Peter ; Washington, Richard, Adriana ; Martins}, title = {A detailed characterization of the Saharan dust collected during the Fennec campaign in 2011: in situ ground-based and laboratory measurements}, journal = {Atmospheric Chemistry And Physics}, year = {2018}, volume = {18}, pages = {1023--1043} } |
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Rocha, W., Metcalfe, D., Doughty, C., Brando, P., Silvério, D., Halladay, K., Nepstad, D., Balch, J. and Malhi, Y. | Ecosystem productivity and carbon cycling in intact and annually burnt forest at the dry southern limit of the Amazon rainforest (Mato Grosso, Brazil) [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 25-40 |
article | |
BibTeX:
@article{rocha_ecosystem_2014, author = {Rocha, W. and Metcalfe, D.B. and Doughty, C.E. and Brando, P. and Silvério, D. and Halladay, K. and Nepstad, D.C. and Balch, J.K. and Malhi, Y.}, title = {Ecosystem productivity and carbon cycling in intact and annually burnt forest at the dry southern limit of the Amazon rainforest (Mato Grosso, Brazil)}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {25--40} } |
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Rocha, K., Moreira, A.R.B., Reis, E.J. and Carvalho, L. | The market value of forest concessions in the Brazilian Amazon: a Real Option approach | 2006 | Forest Policy and Economics Vol. 8(2), pp. 149-160 |
article | DOI URL |
Abstract: The Brazilian government currently implements a concession policy to exploit timber harvesting on national forestry reserves in the Amazon region. This paper applies Real Options to appraise the market value of these forest concessions and quantifies the economic benefits of forest management and regulatory policies. Timber prices are assumed to follow two hypotheses regarding the stochastic process, i.e., Geometric Brownian and Mean Reversion. Corresponding estimates and the implications for the concession market value are analyzed. Biomass volume follows the standard stochastic differential equation from the population ecology literature. For the base case parameters, the market value of forest concession under option pricing is at least 50% higher than the traditional discounted cash flow approach. A lifetime longer than 15 years does not show a significant increase in the concession value. Forest management increases the market value of the concession by at least 30% according to Real Option approach, while the traditional technique fails in quantifying a gain and hence discourages forest management. Since forest concessions are public resources, differences of that magnitude are not negligible. Therefore, the market value of a forest concession given by Real Option arises as an important element for the bidding process and for government policy regarding forest concessions. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{rocha_market_2006, author = {Rocha, K. and Moreira, A. R. B. and Reis, E. J. and Carvalho, L.}, title = {The market value of forest concessions in the Brazilian Amazon: a Real Option approach}, journal = {Forest Policy and Economics}, year = {2006}, volume = {8}, number = {2}, pages = {149--160}, url = {://WOS:000236589600004}, doi = {https://doi.org/10.1016/j.forpol.2004.05.008} } |
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Rocha, H.R., Manzi, A.O., Cabral, O.M., Miller, S.D., Goulden, M.L., Saleska, S.R., Coupe, N.R., Wofsy, S.C., Borma, L.S., Artaxo, P., Vourlitis, G., Nogueira, J.S., Cardoso, F.L., Nobre, A.D., Kruijt, B., Freitas, H.C., von Randow, C., Aguiar, R.G. and Maia, J.F. | Patterns of water and heat flux across a biome gradient from tropical forest to savanna in Brazil | 2009 | Journal of Geophysical Research-Biogeosciences Vol. 114 |
article | DOI URL |
Abstract: We investigated the seasonal patterns of water vapor and sensible heat flux along a tropical biome gradient from forest to savanna. We analyzed data from a network of flux towers in Brazil that were operated within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). These tower sites included tropical humid and semideciduous forest, transitional forest, floodplain (with physiognomies of cerrado), and cerrado sensu stricto. The mean annual sensible heat flux at all sites ranged from 20 to 38 Wm(-2), and was generally reduced in the wet season and increased in the late dry season, coincident with seasonal variations of net radiation and soil moisture. The sites were easily divisible into two functional groups based on the seasonality of evaporation: tropical forest and savanna. At sites with an annual precipitation above 1900 mm and a dry season length less than 4 months (Manaus, Santarem and Rondonia), evaporation rates increased in the dry season, coincident with increased radiation. Evaporation rates were as high as 4.0 mm d(-1) in these evergreen or semidecidous forests. In contrast, ecosystems with precipitation less than 1700 mm and a longer dry season (Mato Grosso, Tocantins and Sao Paulo) showed clear evidence of reduced evaporation in the dry season. Evaporation rates were as low as 2.5 mm d(-1) in the transitional forests and 1 mm d(-1) in the cerrado. The controls on evapotranspiration seasonality changed along the biome gradient, with evaporative demand (especially net radiation) playing a more important role in the wetter forests, and soil moisture playing a more important role in the drier savannah sites. | |||||
BibTeX:
@article{rocha_patterns_2009, author = {Rocha, Humberto R. and Manzi, Antonio O. and Cabral, Osvaldo M. and Miller, Scott D. and Goulden, Michael L. and Saleska, Scott R. and Coupe, Natalia R. and Wofsy, Steven C. and Borma, Laura S. and Artaxo, P. and Vourlitis, George and Nogueira, Jose S. and Cardoso, Fernando L. and Nobre, Antonio D. and Kruijt, Bart and Freitas, Helber C. and von Randow, Celso and Aguiar, Renata G. and Maia, Jair F.}, title = {Patterns of water and heat flux across a biome gradient from tropical forest to savanna in Brazil}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2009}, volume = {114}, url = {://WOS:000262628600001}, doi = {https://doi.org/10.1029/2007jg000640} } |
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Rocha, H.R., Goulden, M.L., Miller, S.D., Menton, M.C., Pinto, L., de Freitas, H.C. and Figueira, A. | Seasonality of water and heat fluxes over a tropical forest in eastern Amazonia | 2004 | Ecological Applications Vol. 14(4), pp. S22-S32 |
article | URL |
Abstract: We used the eddy covariance technique from July 2000 to July 2001 to measure the fluxes of sensible heat, water vapor, and CO, between an old-growth tropical forest in eastern Amazonia and the atmosphere. Precipitation varied seasonally, with a wet season from mid-December 2000 to July 2001 characterized by successive rainy days, wet soil, and,,relative to the dry season, cooler temperatures, greater cloudiness, and reduced incoming solar and net radiation. Average evapotranspiration decreased from 3.96 +/- 0.65 mm/d during the dry season to 3.18 +/- 0.76 mm/d during the wet season, in parallel with decreasing radiation and decreasing water vapor deficit. The average Bowen ratio was 0.17 +/- 0.10, indicating that most of the incoming radiation was used for evaporation. The Bowen ratio was relatively low during the early wet season (December-March), as a result of increased evaporative fraction and reduced sensible heat flux. The seasonal decline in Bowen ratio and increase in evaporative fraction coincided with an increase in ecosystem CO2 assimilation capacity, which we attribute to the growth of new leaves. The evaporative fraction did not decline as the dry season progressed, implying that the forest did not become drought stressed. The roots extracted water throughout the top 250 cm of soil, and water redistribution, possibly by hydraulic lift, partially recharged the shallow soil during dry season nights. The lack of drought stress during the dry season was likely a consequence of deep rooting, and possibly vertical water movement, which allowed the trees to maintain access to soil water year round. | |||||
BibTeX:
@article{rocha_seasonality_2004, author = {Rocha, H. R. and Goulden, M. L. and Miller, S. D. and Menton, M. C. and Pinto, Ldvo and de Freitas, H. C. and Figueira, Ames}, title = {Seasonality of water and heat fluxes over a tropical forest in eastern Amazonia}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S22--S32}, url = {://WOS:000223269000004} } |
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Rocha, E., Sousa, A., Ribeiro, J., Moraes, J., Loureiro, R., Souza, E.B. and Oliveira, M. | Estudo dos recursos hidrológicos da Estação Científica Ferreira Penna (Caxiuanã-PA) na amazônia oriental [BibTeX] |
2006 | Boletim da Sociedade Brasileira de Meteorologia Vol. 30(2-3), pp. 33-38 |
article | |
BibTeX:
@article{rocha_estudo_2006, author = {Rocha, E.J.P. and Sousa, A.M.L. and Ribeiro, J.B.M. and Moraes, J.C. and Loureiro, R.S. and Souza, E. B. and Oliveira, M.C.F.}, title = {Estudo dos recursos hidrológicos da Estação Científica Ferreira Penna (Caxiuanã-PA) na amazônia oriental}, journal = {Boletim da Sociedade Brasileira de Meteorologia}, year = {2006}, volume = {30}, number = {2-3}, pages = {33--38} } |
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Rocha Sousa, A.&.C.C.E. | Estudo observacional de jatos de baixos níveis ocorridos no litoral norte e nordeste do estado do Pará durante os períodos chuvoso (2002) e seco (2003) [BibTeX] |
2006 | Revista Brasileira de Meterologia Vol. 21(2), pp. 170-179 |
article | |
BibTeX:
@article{rocha_estudo_2006-1, author = {Rocha, Sousa, A.M.L. & Campos, C., E.J.P.}, title = {Estudo observacional de jatos de baixos níveis ocorridos no litoral norte e nordeste do estado do Pará durante os períodos chuvoso (2002) e seco (2003)}, journal = {Revista Brasileira de Meterologia}, year = {2006}, volume = {21}, number = {2}, pages = {170--179} } |
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Rocha, C.R.d. and Lyra, R.F.F. | Balanço de energia em área de pastagem na Amazônia ocidental durante estação chuvosa - LBA 2002 [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 153-156 |
article | |
BibTeX:
@article{rocha_balanco_2009, author = {Rocha, Cintia Rabelo da and Lyra, Roberto F. F.}, title = {Balanço de energia em área de pastagem na Amazônia ocidental durante estação chuvosa - LBA 2002}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {153--156} } |
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Rocco, M.R., Pereira, A.J., Vivekanandan, J. and Ams | Microphysical characterization of a squall line in TRMM LBA using dual-polarization radar measurements [BibTeX] |
2003 | 31st Conference on Radar Meteorology, Vols 1 and 2, pp. 575-576 | incollection | URL |
BibTeX:
@incollection{rocco_microphysical_2003, author = {Rocco, M. R. and Pereira, A. J. and Vivekanandan, J. and Ams}, title = {Microphysical characterization of a squall line in TRMM LBA using dual-polarization radar measurements}, booktitle = {31st Conference on Radar Meteorology, Vols 1 and 2}, year = {2003}, pages = {575--576}, url = {://WOS:000223421300165} } |
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Robertson, A.L., Malhi, Y., Farfan-Amezquita, F., Aragao, L.E.O.C., Espejo, J.E.S. and Robertson, M.A. | Stem respiration in tropical forests along an elevation gradient in the Amazon and Andes | 2010 | Global Change Biology Vol. 16(12), pp. 3193-3204 |
article | DOI URL |
Abstract: Autotrophic respiration involves the use of fixed carbon by plants for their own metabolism, resulting in the release of carbon dioxide as a by-product. Little is known of how autotrophic respiration components vary across environmental gradients, particularly in tropical ecosystems. Here, we present stem CO(2) efflux data measured across an elevation transect spanning ca. 2800 m in the Peruvian Amazon and Andes. Forest plots from five elevations were studied: 194, 210, 1000, 1500, and 3025 m asl Stem CO(2) efflux (R(s)) values from each plot were extrapolated to the 1-ha plot level. Mean R(s) per unit stem surface area declined significantly with elevation, from 1.14 +/- 0.12 at 210 m elevation to 0.62 +/- 0.09 mu mol C m-2 s-1 at 3025 m elevation. When adjusted for changing forest structure with elevation, this is equivalent to 6.45 +/- 1.12 Mg C ha-1 yr-1 at 210 m elevation to 2.94 +/- 0.19 Mg C ha-1 yr-1 at 3025 m elevation. We attempted to partition stem respiration into growth and maintenance respiration components for each site. Both growth and maintenance respiration rates per unit stem showed similar, moderately significant absolute declines with elevation, but the proportional decline in growth respiration rates was much greater. Stem area index (SAI) showed little trend along the transect, with declining tree stature at higher elevations being offset by an increased number of small trees. This trend in SAI is sensitive to changes in forest stature or size structure. In the context of rapid regional warming over the 21st century, such indirect, ecosystem-level temperature responses are likely to be as important as the direct effects of temperature on maintenance respiration rates. | |||||
BibTeX:
@article{robertson_stem_2010, author = {Robertson, Amanda L. and Malhi, Yadvinder and Farfan-Amezquita, Filio and Aragao, Luiz Eduardo O. C. and Espejo, Javier Eduardo Silva and Robertson, Matthew A.}, title = {Stem respiration in tropical forests along an elevation gradient in the Amazon and Andes}, journal = {Global Change Biology}, year = {2010}, volume = {16}, number = {12}, pages = {3193--3204}, url = {://WOS:000283726600003}, doi = {https://doi.org/10.1111/j.1365-2486.2010.02314.x} } |
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Roberts, M.C., Andreae, M.O., Zhou, J.C. and Artaxo, P. | Cloud condensation nuclei in the Amazon Basin: "Marine" conditions over a continent? | 2001 | Geophysical Research Letters Vol. 28(14), pp. 2807-2810 |
article | URL |
Abstract: Cloud condensation nuclei (CCN) are linked to radiative forcing, precipitation, and cloud structure; yet, their role in tropical climates remains largely unknown. CCN concentrations (N-CCN) measured during the wet season in the Amazon Basin were surprisingly low (mean N-CCN at 1% supersaturation: 267 +/- 132 cm(-3)) and resembled concentrations more typical of marine locations than most continental sites. At low background CCN concentrations, cloud properties are more sensitive to an increase in N-CCN. Therefore: enhanced aerosol emissions due to human activity in the Amazon Basin may have a stronger impact on climate than emissions in other continental regions. In spite of the large organic fraction in the Amazonian aerosol, a detailed analysis of number distributions and size-dependent chemical composition indicates that sulfate plays an important role in CCN activity. | |||||
BibTeX:
@article{roberts_cloud_2001, author = {Roberts, M. C. and Andreae, M. O. and Zhou, J. C. and Artaxo, P.}, title = {Cloud condensation nuclei in the Amazon Basin: "Marine" conditions over a continent?}, journal = {Geophysical Research Letters}, year = {2001}, volume = {28}, number = {14}, pages = {2807--2810}, url = {://WOS:000169849500035} } |
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Roberts, G.C., Nenes, A., Seinfeld, J.H. and Andreae, M.O. | Impact of biomass burning on cloud properties in the Amazon Basin | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D2) |
article | DOI URL |
Abstract: [1] We used a one-dimensional (1-D) cloud parcel model to assess the impact of biomass-burning aerosol on cloud properties in the Amazon Basin and to identify the physical and chemical properties of the aerosol that influence droplet growth. Cloud condensation nuclei (CCN) measurements were performed between 0.15% and 1.5% supersaturation at ground-based sites in the states of Amazonas and Rondonia, Brazil during several field campaigns in 1998 and 1999 as part of the Large-Scale Biosphere - Atmosphere (LBA) Experiment in Amazonia. CCN concentrations measured during the wet season were low and resembled concentrations more typical of marine conditions than most continental sites. During the dry season, smoke aerosol from biomass burning dramatically increased CCN concentrations. The modification of cloud properties, such as cloud droplet effective radius and maximum supersaturation, is most sensitive at low CCN concentrations. Hence, we could expect larger interannual variation of cloud properties during the wet season that the dry season. We found that differences between CCN spectra from forested and deforested regions during the wet season are modest and result in modifications of cloud properties that are small compared to those between wet and dry seasons. Our study suggests that the differences in surface albedo, rather than cloud albedo, between forested and deforested regions may dominate the impact of deforestation on the hydrological cycle and convective activity during the wet season. During the dry season, on the other hand, cloud droplet concentrations may increase by up to 7 times, which leads to a model-predicted decrease in cloud effective radius by a factor of 2. This could imply a maximum indirect radiative forcing due to aerosol as high as ca. -27 W m(-2) for a nonabsorbing cloud. Light-absorbing substances in smoke darken the Amazonian clouds and reduce the net radiative forcing, and a comparison of the Advanced Very High Resolution Radiometer (AVHRR) analysis and our modeling studies suggests that absorption of sunlight due to smoke aerosol may compensate for about half of the maximum aerosol effect. Sensitivity tests show that complete characterization of the aerosol is necessary when kinetic growth limitations become important. Subtle differences in the chemical and physical makeup are shown to be particularly influential in the activation and growth behavior of the aerosol. Knowledge of the CCN spectrum alone is not sufficient to fully capture the climatic influence of biomass burning. | |||||
BibTeX:
@article{roberts_impact_2003, author = {Roberts, G. C. and Nenes, A. and Seinfeld, J. H. and Andreae, M. O.}, title = {Impact of biomass burning on cloud properties in the Amazon Basin}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D2}, url = {://WOS:000181824500001}, doi = {https://doi.org/10.1029/2001jd000985} } |
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Roberts, G.C., Artaxo, P., Zhou, J.C., Swietlicki, E. and Andreae, M.O. | Sensitivity of CCN spectra on chemical and physical properties of aerosol: A case study from the Amazon Basin | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Organic material, about half of which is water soluble, constitutes nearly 80% of the wet-season aerosol mass in the Amazon Basin, while soluble inorganic salts (predominantly ammonium bisulfate) represent about 15%. A detailed analysis of number distributions and the size-dependent chemical composition of the aerosol indicates that, in principle, the sulfate fraction could account for most of the cloud condensation nuclei (CCN) activity. Uncertainty about the chemical speciation of the water-soluble organic component precludes a rigorous analysis of its contribution to nucleation activity. Within reasonable assumptions, we can, however, predict a similar contribution of the organic component to CCN activity as that from sulfate. Because of the nonlinear dependence of droplet nucleation behavior on solute amount, the nucleation activity cannot be attributed uniquely to the inorganic or organic fractions. The role of water-soluble organic compounds as surfactants, however, may be significant (especially in the case of biomass-burning aerosol) and more field measurements are needed to quantify their effects on the surface tension of ambient aerosols. The parametric dependence of the CCN spectra on the physical and chemical properties of the aerosol show that the number distribution, soluble content of the aerosol, and surface tension effects all play an important role in determining CCN spectra. | |||||
BibTeX:
@article{roberts_sensitivity_2002, author = {Roberts, G. C. and Artaxo, P. and Zhou, J. C. and Swietlicki, E. and Andreae, M. O.}, title = {Sensitivity of CCN spectra on chemical and physical properties of aerosol: A case study from the Amazon Basin}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200026}, doi = {https://doi.org/10.1029/2001jd000583} } |
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Roberts, G.C., Andreae, M.O., Maenhaut, W. and Fernandez-Jimenez, M.T. | Composition and sources of aerosol in a central African rain forest during the dry season | 2001 | Journal of Geophysical Research-Atmospheres Vol. 106(D13), pp. 14423-14434 |
article | DOI URL |
Abstract: During the Experiment for Regional Sources and Sinks of Oxidants (EXPRESSO-96), size-fractionated aerosol samples were collected in November and December 1996 at a ground site in the tropical rain forest at the N'doki National Park (NNP) in the Republic of Congo. The samples were analyzed for up to 26 elements using particle-induced X-ray emission. Elements related to mineral dust and pyrogenic aerosol exhibited greater concentrations during the daytime, while aerosol produced by the rain forest exhibited higher concentrations at night. Samples were also collected at two levels on the tower, above and below the canopy, to characterize vegetation sources. Absolute principal component analysis (APCA) identified three major aerosol source types in each size fraction, which explained more than 90% of the data variance. The fine-size fraction contained mineral dust (Al, Si, Ca, Ti, and Fe), pyrogenic (black carbon, K, and Zn), and marine/anthropogenic sulfur components. The coarse-size fraction included a mineral dust (Al, Si, Ca, Ti, Mn, and Fe) and two primary biogenic components consisting of K, P, Zn, and S. Absolute principal component scores were calculated for the components of APCA, and temporal trends were compared to 7 day isopycnic backward trajectories. Consistent relationships between the temporal trends of the fine fraction aerosol components and meteorological patterns were observed. Trade wind air masses transported biomass burning and mineral dust aerosol to NNP during the first half of the experiment. The fine fraction sulfur component correlated well with the pyrogenic activity before the change in meteorological patterns halfway through the experiment. The fine and coarse sulfur concentrations nearly doubled in the latter part of the experiment as a monsoon circulation brought sulfur-enriched aerosol from the Atlantic Ocean. Various industrial activities on the coast of Cameroon and Gabon probably contributed to the high sulfur concentrations as well. | |||||
BibTeX:
@article{roberts_composition_2001, author = {Roberts, G. C. and Andreae, M. O. and Maenhaut, W. and Fernandez-Jimenez, M. T.}, title = {Composition and sources of aerosol in a central African rain forest during the dry season}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2001}, volume = {106}, number = {D13}, pages = {14423--14434}, url = {://WOS:000169903900018}, doi = {https://doi.org/10.1029/2000jd900774} } |
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Roberts, G.C. and Andreae, M.O. | Reply to "Comment on Cloud condensation nuclei in the Amazon Basin: "Marine" conditions over a continent?" by P. J. Crutzen et al [BibTeX] |
2003 | Geophysical Research Letters Vol. 30(2) |
article | DOI URL |
BibTeX:
@article{roberts_reply_2003, author = {Roberts, G. C. and Andreae, M. O.}, title = {Reply to "Comment on Cloud condensation nuclei in the Amazon Basin: "Marine" conditions over a continent?" by P. J. Crutzen et al}, journal = {Geophysical Research Letters}, year = {2003}, volume = {30}, number = {2}, url = {://WOS:000182892600003}, doi = {https://doi.org/10.1029/2002gl015564} } |
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Roberts, D.A., Numata, I., Holmes, K., Batista, G., Krug, T., Monteiro, A., Powell, B. and Chadwick, O.A. | Large area mapping of land-cover change in Rondonia using multitemporal spectral mixture analysis and decision tree classifiers | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] We describe spatiotemporal variation in land cover over 80,000 km 2 in central Rondonia. We use a multistage process to map primary forest, pasture, second growth, urban, rock/savanna, and water using 33 Landsat scenes acquired over three contiguous areas between 1975 and 1999. Accuracy of the 1999 classified maps was assessed as exceeding 85% based on digital airborne videography. Rondonia is highly fragmented, in which forests outside of restricted areas consist of numerous, small irregular patches. Pastures in Rondonia persist over many years and are not typically abandoned to second growth, which when present rarely remains unchanged longer than 8 years. Within the state, annual deforestation rates, pasture area, and ratio of second growth to cleared area varied spatially. Highest initial deforestation rates occurred in the southeast (Luiza), at over 2%, increasing to 3% by the late 1990s. In this area, the percentage of cleared land in second growth averaged 18% and few pastures were abandoned. In central Rondonia (Ji-Parana), deforestation rates rose from 1.2% between 1978 and 1986 to a high of 4.2% in 1999. In the northwest (Ariquemes), initial deforestation rates were lowest at 0.5% but rose substantially in the late 1990s, peaking at 3% in 1998. The ratio of second growth to cleared area was more than double the ratio in Luiza and few pastures remained unchanged beyond 8 years. Land clearing was most intense close to the major highway, BR364, except in Ariquemes. Intense forest clearing extended at least 50 km along the margins of BR364 in Ji-Parana and Luiza. Spatial differences in land use are hypothesized to result from a combination of economic factors and soil fertility. | |||||
BibTeX:
@article{roberts_large_2002, author = {Roberts, D. A. and Numata, I. and Holmes, K. and Batista, G. and Krug, T. and Monteiro, A. and Powell, B. and Chadwick, O. A.}, title = {Large area mapping of land-cover change in Rondonia using multitemporal spectral mixture analysis and decision tree classifiers}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200001}, doi = {https://doi.org/10.1029/2001jd000374} } |
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Roberts, D.A., Keller, M. and Soares, J.V. | Studies of land-cover, land-use, and biophysical properties of vegetation in the Large Scale Biosphere Atmosphere experiment in Amazonia | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 377-388 |
article | DOI URL |
Abstract: We summarize early research on land-cover, land-use, and biophysical properties of vegetation from the Large Scale Biosphere Atmosphere (LBA) experiment in Amazonia. LBA is an international research program developed to evaluate regional function and to determine how land-use and climate modify biological, chemical and physical processes there. Remote sensing has played a fundamental role in LBA in research planning, land-cover mapping and in long-term monitoring of changes in land-cover and land-use at multiple scales. This special issue includes 12 papers that cover a range in spatial scales from regional mapping to local scales that cover only a portion of a Landsat scene. Several themes dominate, including land-cover mapping with an emphasis on wetlands and second-growth forest, evaluation of pasture sustainability and forest degradation and the impact of land-cover change on stream chemistry. New techniques introduced include automated Monte Carlo unmixing (AutoMCU) and several new approaches for mapping land-cover. A diversity of sensors are utilized, including ETM+, IKONOS, SPOT-4, Airborne P-band synthetic aperture radar (SAR), and L-band SAR. Census data are fused with an existing land-cover map to generate spatially explicit estimates of land-use from historical data. Several papers include important, new field measures of species composition, forest structure and biomass in mature forest and secondary succession. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{roberts_studies_2003, author = {Roberts, D. A. and Keller, M. and Soares, J. V.}, title = {Studies of land-cover, land-use, and biophysical properties of vegetation in the Large Scale Biosphere Atmosphere experiment in Amazonia}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {377--388}, url = {://WOS:000186827400001}, doi = {https://doi.org/10.1016/j.rse.2003.08.012} } |
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Rizzolo, C.G.G., Borillo, G.C., Godoi, A.F.L., Souza, R.A.F., Andreoli, R.V., Manzi, A.O., Sá, M.O., Alves, E.G., Pöhlker, C., Angelis, I.H., Ditas, F., Saturno, J., Moran-Zuloaga, D., Rizzo, L.V., Rosário, N.E., Pauliquevis, T., Yamamoto, C.I., Andreae, M.O., Taylor, P.E., Godoi Ricardo H. M., J.A. and Barbosa | Soluble iron nutrients in Saharan dust over the central Amazon rainforest [BibTeX] |
2017 | Atmospheric Chemistry and Physics Vol. 17, pp. 2673-2687 |
article | DOI |
BibTeX:
@article{rizzolo_soluble_2017, author = {Rizzolo, Cybelli G. G. ; Borillo, Guilherme C. ; Godoi, Ana F. L. ; Souza, Rodrigo A. F. ; Andreoli, Rita V. ; Manzi, Antonio O. ; Sá, Marta O. ; Alves, Eliane G. ; Pöhlker, Christopher ; Angelis, Isabella H. ; Ditas, Florian ; Saturno, Jorge ; Moran-Zuloaga, Daniel ; Rizzo, Luciana V. ; Rosário, Nilton E. ; Pauliquevis, Theotonio ; Yamamoto, Carlos I. ; Andreae, Meinrat O. ; Taylor, Philip E. ; Godoi, Ricardo H. M., Joana A. ; Barbosa}, title = {Soluble iron nutrients in Saharan dust over the central Amazon rainforest}, journal = {Atmospheric Chemistry and Physics}, year = {2017}, volume = {17}, pages = {2673--2687}, doi = {https://doi.org/10.5194/acp-2016-557} } |
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Rizzo, L., Roldin, P., Brito, J., Backman, J., Swietlicki, E., Krejci, R., Tunved, P., Petäjä, T., Kulmala, M. and Artaxo, P. | Multi-year statistical and modelling analysis of submicrometer aerosol number size distributions at a rain forest site in Amazonia [BibTeX] |
2018 | Atmos. Chem. Phys. Discuss. | article | DOI |
BibTeX:
@article{rizzo_multi-year_2018, author = {Rizzo, L.V. and Roldin, P. and Brito, J. and Backman, J. and Swietlicki, E. and Krejci, R. and Tunved, P. and Petäjä, T. and Kulmala, M. and Artaxo, P.}, title = {Multi-year statistical and modelling analysis of submicrometer aerosol number size distributions at a rain forest site in Amazonia}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2018}, doi = {https://doi.org/10.5194/acp-2018-55} } |
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Rizzo, L.V., Correia, A.L., Artaxo, P., Procopio, A.S. and Andreae, M.O. | Spectral dependence of aerosol light absorption over the Amazon Basin | 2011 | Atmospheric Chemistry and Physics Vol. 11(17), pp. 8899-8912 |
article | DOI URL |
Abstract: In this study, we examine the spectral dependence of aerosol absorption at different sites and seasons in the Amazon Basin. The analysis is based on measurements performed during three intensive field experiments at a pasture site (Fazenda Nossa Senhora, Rondonia) and at a primary forest site (Cuieiras Reserve, Amazonas), from 1999 to 2004. Aerosol absorption spectra were measured using two Aethalometers: a 7-wavelength Aethalometer (AE30) that covers the visible (VIS) to near-infrared (NIR) spectral range, and a 2-wavelength Aethalometer (AE20) that measures absorption in the UV and in the NIR. As a consequence of biomass burning emissions, about 10 times greater absorption values were observed in the dry season in comparison to the wet season. Power law expressions were fitted to the measurements in order to derive the absorption Angstrom exponent, defined as the negative slope of absorption versus wavelength in a log-log plot. At the pasture site, about 70% of the absorption Angstrom exponents fell between 1.5 and 2.5 during the dry season, indicating that biomass burning aerosols have a stronger spectral dependence than soot carbon particles. Angstrom exponents decreased from the dry to the wet season, in agreement with the shift from biomass burning aerosols, predominant in the fine mode, to biogenic and dust aerosols, predominant in the coarse mode. The lowest absorption Angstrom exponents (90% of data below 1.5) were observed at the forest site during the dry season. Also, results indicate that low absorption coefficients were associated with low Angstrom exponents. This finding suggests that biogenic aerosols from Amazonia have a weaker spectral dependence for absorption than biomass burning aerosols, contradicting our expectations of biogenic particles behaving as brown carbon. In a first order assessment, results indicate a small (textless1 %) effect of variations in absorption Angstrom exponents on 24-h aerosol forcings, at least in the spectral range of 450-880 nm. Further studies should be taken to assess the corresponding impact in the UV spectral range. The assumption that soot spectral properties represent all ambient light absorbing particles may cause a misjudgment of absorption towards the UV, especially in remote areas. Therefore, it is recommended to measure aerosol absorption at several wavelengths to accurately assess the impact of non-soot aerosols on climate and on photochemical atmospheric processes. | |||||
BibTeX:
@article{rizzo_spectral_2011, author = {Rizzo, L. V. and Correia, A. L. and Artaxo, P. and Procopio, A. S. and Andreae, M. O.}, title = {Spectral dependence of aerosol light absorption over the Amazon Basin}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, number = {17}, pages = {8899--8912}, url = {://WOS:000294809200005}, doi = {https://doi.org/10.5194/acp-11-8899-2011} } |
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Rizzo, L., Artaxo, P., Muller, T., Wiedensohler, A., Paixao, M., Cirino, G., Arana, A., Swietlicki, E., Roldin, P., Fors, E., Wiedemann, K., Leal, L. and Kulmala, M. | Long term measurements of aerosol optical properties at a pristine forest site in Amazonia [BibTeX] |
2013 | Atmos. Chem. Phys. Vol. 12, pp. 23333-23401 |
article | |
BibTeX:
@article{rizzo_long_2013, author = {Rizzo, L.V. and Artaxo, P. and Muller, T. and Wiedensohler, A. and Paixao, M. and Cirino, G.G. and Arana, A. and Swietlicki, E. and Roldin, P. and Fors, E.O. and Wiedemann, K.T. and Leal, L.S.M. and Kulmala, M.}, title = {Long term measurements of aerosol optical properties at a pristine forest site in Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2013}, volume = {12}, pages = {23333--23401} } |
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Rizzo, L.V., Artaxo, P., Karl, T., Guenther, A.B. and Greenberg, J. | Aerosol properties, in-canopy gradients, turbulent fluxes and VOC concentrations at a pristine forest site in Amazonia | 2010 | Atmospheric Environment Vol. 44(4), pp. 503-511 |
article | DOI URL |
Abstract: Aerosol physical and chemical properties were measured in a forest site in central Amazonia (Cuieiras reservation, 2.61S; 60.21W) during the dry season of 2004 (Aug-Oct). Aerosol light scattering and absorption, mass concentration, elemental composition and size distributions were measured at three tower levels (Ground: 2 m; Canopy: 28 m, and Top: 40 m). For the first time, simultaneous eddy covariance fluxes of fine mode particles and volatile organic compounds (VOC) were measured above the Amazonian forest canopy. Aerosol fluxes were measured by eddy covariance using a Condensation Particle Counter (CPC) and a sonic anemometer. VOC fluxes were measured by disjunct eddy covariance using a Proton Transfer Reaction Mass Spectrometer (PTR-MS). At nighttime, a strong vertical gradient of phosphorus and potassium in the aerosol coarse mode was observed, with higher concentrations at Ground level. This suggests a source of primary biogenic particles below the canopy. Equivalent black carbon measurements indicate the presence of light-absorbing aerosols from biogenic origin. Aerosol number size distributions typically consisted of superimposed Aitken (76 nm) and accumulation modes (144 nm), without clear events of new particle formation. Isoprene and monoterpene fluxes reached respectively 7.4 and 0.82 mg m(-2) s(-1) around noon. An average fine particle flux of 0.05 +/- 0.10 10(6) m(-2) s(-1) was calculated, denoting an equilibrium between emission and deposition fluxes of fine mode particles at daytime. No significant correlations were found between VOC and fine mode aerosol concentrations or fluxes. (C) 2009 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{rizzo_aerosol_2010, author = {Rizzo, L. V. and Artaxo, P. and Karl, T. and Guenther, A. B. and Greenberg, J.}, title = {Aerosol properties, in-canopy gradients, turbulent fluxes and VOC concentrations at a pristine forest site in Amazonia}, journal = {Atmospheric Environment}, year = {2010}, volume = {44}, number = {4}, pages = {503--511}, url = {://WOS:000274614300007}, doi = {https://doi.org/10.1016/j.atmosenv.2009.11.002} } |
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Rissler, J., Vestin, A., Swietlicki, E., Fisch, G., Zhou, J., Artaxo, P. and Andreae, M.O. | Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 471-491 |
article | URL |
Abstract: Aerosol particle number size distributions and hygroscopic properties were measured at a pasture site in the southwestern Amazon region (Rondonia). The measurements were performed 11 September-14 November 2002 as part of LBA-SMOCC (Large scale Biosphere atmosphere experiment in Amazonia - SMOke aerosols, Clouds, rainfall and Climate), and cover the later part of the dry season (with heavy biomass burning), a transition period, and the onset of the wet period. Particle number size distributions were measured with a DMPS (Differential Mobility Particle Sizer, 3-850 nm) and an APS (Aerodynamic Particle Sizer), extending the distributions up to 3.3 mu m in diameter. An H-TDMA (Hygroscopic Tandem Differential Mobility Analyzer) measured the hygroscopic diameter growth factors (Gf) at 90% relative humidity (RH), for particles with dry diameters (d(p)) between 20-440 nm, and at several occasions RH scans (30-90% RH) were performed for 165 nm particles. These data provide the most extensive characterization of Amazonian biomass burning aerosol, with respect to particle number size distributions and hygroscopic properties, presented until now. The evolution of the convective boundary layer over the course of the day causes a distinct diel variation in the aerosol physical properties, which was used to get information about the properties of the aerosol at higher altitudes. The number size distributions averaged over the three defined time periods showed three modes; a nucleation mode with geometrical median diameters (GMD) of similar to 12 nm, an Aitken mode (GMD=61-92 nm) and an accumulation mode (GMD=128-190 nm). The two larger modes were shifted towards larger GMD with increasing influence from biomass burning. The hygroscopic growth at 90% RH revealed a somewhat external mixture with two groups of particles; here denoted nearly hydrophobic (Gf similar to 1.09 for 100 nm particles) and moderately hygroscopic (Gf similar to 1.26). While the hygroscopic growth factors were surprisingly similar over the periods, the number fraction of particles belonging to each hygroscopic group varied more, with the dry period aerosol being more dominated by nearly hydrophobic particles. As a result the total particle water uptake rose going into the cleaner period. The fraction of moderately hygroscopic particles was consistently larger for particles in the accumulation mode compared to the Aitken mode for all periods. Scanning the H-TDMA over RH (30-90% RH) showed no deliquescence behavior. A parameterization of both Gf(RH) and Gf(d(p)), is given. | |||||
BibTeX:
@article{rissler_size_2006, author = {Rissler, J. and Vestin, A. and Swietlicki, E. and Fisch, G. and Zhou, J. and Artaxo, P. and Andreae, M. O.}, title = {Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {471--491}, url = {://WOS:000235230500001} } |
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Rissler, J., Swietlicki, E., Zhou, J., Roberts, G., Andreae, M.O., Gatti, L.V. and Artaxo, P. | Physical properties of the sub-micrometer aerosol over the Amazon rain forest during the wet-to-dry season transition - comparison of modeled and measured CCN concentrations | 2004 | Atmospheric Chemistry and Physics Vol. 4, pp. 2119-2143 |
article | URL |
Abstract: Sub-micrometer atmospheric aerosol particles were studied in the Amazon region, 125 km northeast of Manaus, Brazil (-1degrees55.2'S, 59degrees28.1'W). The measurements were performed during the wet-to-dry transition period, 4-28 July 2001 as part of the LBA (Large-Scale Biosphere Atmosphere Experiment in Amazonia) CLAIRE-2001 (Cooperative LBA Airborne Regional Experiment) experiment. The number size distribution was measured with two parallel differential mobility analyzers, the hygroscopic growth at 90% RH with a Hygroscopic Tandem Mobility Analyzer (H-TDMA) and the concentrations of cloud condensation nuclei (CCN) with a cloud condensation nuclei counter. A model was developed that uses the H-TDMA data to predict the number of soluble molecules or ions in the individual particles and the corresponding minimum particle diameter for activation into a cloud droplet at a certain supersaturation. Integrating the number size distribution above this diameter, CCN concentrations were predicted with a time resolution of 10 min and compared to the measured concentrations. During the study period, three different air masses were identified and compared: clean background, air influenced by aged biomass burning, and moderately polluted air from recent local biomass burning. For the clean period 2001, similar number size distributions and hygroscopic behavior were observed as during the wet season at the same site in 1998, with mostly internally mixed particles of low diameter growth factor (similar to1.3 taken from dry to 90% RH). During the periods influenced by biomass burning the hygroscopic growth changed slightly, but the largest difference was seen in the number size distribution. The CCN model was found to be successful in predicting the measured CCN concentrations, typically within 25%. A sensitivity study showed relatively small dependence on the assumption of which model salt that was used to predict CCN concentrations from H-TDMA data. One strength of using H-TDMA data to predict CCN concentrations is that the model can also take into account soluble organic compounds, insofar as they go into solution at 90% RH. Another advantage is the higher time resolution compared to using size-resolved chemical composition data. | |||||
BibTeX:
@article{rissler_physical_2004, author = {Rissler, J. and Swietlicki, E. and Zhou, J. and Roberts, G. and Andreae, M. O. and Gatti, L. V. and Artaxo, P.}, title = {Physical properties of the sub-micrometer aerosol over the Amazon rain forest during the wet-to-dry season transition - comparison of modeled and measured CCN concentrations}, journal = {Atmospheric Chemistry and Physics}, year = {2004}, volume = {4}, pages = {2119--2143}, url = {://WOS:000224840800001} } |
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Rinne, H.J.I., Guenther, A.B., Greenberg, J.P. and Harley, P.C. | Isoprene and monoterpene fluxes measured above Amazonian rainforest and their dependence on light and temperature | 2002 | Atmospheric Environment Vol. 36(14), pp. 2421-2426 |
article | DOI URL |
Abstract: Canopy scale emissions of isoprene and monoterpenes from Amazonian rainforest were measured by eddy covariance and eddy accumulation techniques. The peak mixing ratios at about 10 in above the canopy occurred in the afternoon and were typically about 90 ppt(v) of alpha-pinene and 4-5ppb(v) of isoprene. alpha-pinene was the most abundant monoterpene in the air above the canopy comprising 50% of the total monoterpene mixing ratio. Measured isoprene fluxes were almost 10 times higher than alpha-pinene fluxes. Normalized conditions of 30 degreesC and 1000 mumol m(-2) s(-1) were associated with an isoprene flux of 2.4 mg m(-2) h(-1) and a beta-pinene flux of 0.26 mg m(-2) h(-1). Both fluxes were lower than values that have been specified for Amazon rainforests in global emission models. Isoprene flux correlated with a light- and temperature-dependent emission activity factor, and even better with measured sensible heat flux. The variation in the measured a-pinene fluxes, as well as the diurnal cycle of mixing ratio, suggest emissions that are dependent oil both light and temperature. The light and temperature dependence can have a significant effect on the modeled diurnal cycle of monoterpene emission as well as on the total monoterpene emission. (C) 2002 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{rinne_isoprene_2002, author = {Rinne, H. J. I. and Guenther, A. B. and Greenberg, J. P. and Harley, P. C.}, title = {Isoprene and monoterpene fluxes measured above Amazonian rainforest and their dependence on light and temperature}, journal = {Atmospheric Environment}, year = {2002}, volume = {36}, number = {14}, pages = {2421--2426}, url = {://WOS:000176431500013}, doi = {https://doi.org/10.1016/s1352-2310(01)00523-4} } |
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Rindfuss, R.R., Walsh, S.J., Turner, B.L., Fox, J. and Mishra, V. | Developing a science of land change: Challenges and methodological issues | 2004 | Proceedings of the National Academy of Sciences of the United States of America Vol. 101(39), pp. 13976-13981 |
article | DOI URL |
Abstract: Land-change science has emerged as a foundational element of global environment change and sustainability science. It seeks to understand the human and environment dynamics that give rise to changed land uses and covers, not only in terms of their type and magnitude but their location as well. This focus requires the integration of social, natural, and geographical information sciences. Each of these broad research communities has developed different ways to enter the land-change problem, each with different means of treating the locational specificity of the critical variables, such as linking the land manager to the parcel being managed. The resulting integration encounters various data, methodological, and analytical problems, especially those concerning aggregation and inference, land-use pixel links, data and measurement, and remote sensing analysis. Here, these integration problems, which hinder comprehensive understanding and theory development, are addressed. Their recognition and resolution are required for the sustained development of land-change science. | |||||
BibTeX:
@article{rindfuss_developing_2004, author = {Rindfuss, R. R. and Walsh, S. J. and Turner, B. L. and Fox, J. and Mishra, V.}, title = {Developing a science of land change: Challenges and methodological issues}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2004}, volume = {101}, number = {39}, pages = {13976--13981}, note = {Edition: 2004/09/24}, url = {://WOS:000224211400003}, doi = {https://doi.org/10.1073/pnas.0401545101} } |
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Rifai, S., Urquiza Muñoz, J., Negrón-Juárez, R., Ramírez Arévalo, F., Tello-Espinoza, R., Vanderwel, M., Lichstein, J., Chambers, J. and Bohlman, S. | Landscape-scale consequences of differential tree mortality from catastrophic wind disturbance in the Amazon [BibTeX] |
2016 | Ecological Applications Vol. 26(7) |
article | DOI |
BibTeX:
@article{rifai_landscape-scale_2016, author = {Rifai, S.W. and Urquiza Muñoz, J.D. and Negrón-Juárez, R.I. and Ramírez Arévalo, F.R. and Tello-Espinoza, R. and Vanderwel, M.C. and Lichstein, J.W. and Chambers, J.Q. and Bohlman, S.A.}, title = {Landscape-scale consequences of differential tree mortality from catastrophic wind disturbance in the Amazon}, journal = {Ecological Applications}, year = {2016}, volume = {26}, number = {7}, doi = {https://doi.org/10.1002/eap.1368} } |
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Ricketts, T.H., Soares-Filho, B., da Fonseca, G.A.B., Nepstad, D., Pfaff, A., Petsonk, A., Anderson, A., Boucher, D., Cattaneo, A., Conte, M., Creighton, K., Linden, L., Maretti, C., Moutinho, P., Ullman, R. and Victurine, R. | Indigenous Lands, Protected Areas, and Slowing Climate Change | 2010 | Plos Biology Vol. 8(3), pp. e1000331 |
article | DOI URL |
Abstract: Recent climate talks in Copenhagen reaffirmed the crucial role of reducing emissions from deforestation and degradation (REDD). Creating and strengthening indigenous lands and other protected areas represents an effective, practical, and immediate REDD strategy that addresses both biodiversity and climate crises at once. | |||||
BibTeX:
@article{ricketts_indigenous_2010, author = {Ricketts, Taylor H. and Soares-Filho, Britaldo and da Fonseca, Gustavo A. B. and Nepstad, Daniel and Pfaff, Alexander and Petsonk, Annie and Anderson, Anthony and Boucher, Doug and Cattaneo, Andrea and Conte, Marc and Creighton, Ken and Linden, Lawrence and Maretti, Claudio and Moutinho, Paulo and Ullman, Roger and Victurine, Ray}, title = {Indigenous Lands, Protected Areas, and Slowing Climate Change}, journal = {Plos Biology}, year = {2010}, volume = {8}, number = {3}, pages = {e1000331}, note = {Edition: 2010/03/23}, url = {://WOS:000278125400010}, doi = {https://doi.org/10.1371/journal.pbio.1000331} } |
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Rickenbach, T.M., Ferreira, R.N., Halverson, J.B., Herdies, D.L. and Dias, M. | Modulation of convection in the southwestern Amazon basin by extratropical stationary fronts | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] Regimes of lower tropospheric northwesterly wind observed in southwestern Amazonia during the Tropical Rainfall Measuring Mission Large-Scale Biosphere Atmosphere (TRMM-LBA) field campaign were shown to be local manifestations of stationary frontal systems that extended into the deep Tropics along the South Atlantic Convergence Zone ("SACZ'' regime). Frontal systems were transient and were confined to the subtropics during the interim periods of easterly and weak westerly flow ("non-SACZ'' regime). Observations from surface-based radar in TRMM-LBA suggested that mesoscale convective systems in the SACZ regime were significantly larger in areal coverage, with weaker rainfall intensity and weaker vertical development of the convective cells. The diurnal variation of rain intensity and rain areal coverage generally showed afternoon maxima for both regimes, but with important differences suggesting explosive convective cell growth in the non-SACZ regime and the dominance of nocturnal stratiform rain processes in the SACZ regime. These results had implications for the parameterization (in general circulation models) of subgrid-scale convective processes in Amazonia in terms of the large-scale flow and for improving precipitation and latent heating retrieval from spaceborne platforms such as the TRMM satellite. | |||||
BibTeX:
@article{rickenbach_modulation_2002, author = {Rickenbach, T. M. and Ferreira, R. N. and Halverson, J. B. and Herdies, D. L. and Dias, Mafs}, title = {Modulation of convection in the southwestern Amazon basin by extratropical stationary fronts}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180336500005}, doi = {https://doi.org/10.1029/2000jd000263} } |
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Rickenbach, T.M. | Nocturnal cloud systems and the diurnal variation of clouds and rainfall in southwestern Amazonia | 2004 | Monthly Weather Review Vol. 132(5), pp. 1201-1219 |
article | DOI URL |
Abstract: This paper examines the origins of a secondary nocturnal maximum in cloudiness and precipitation in southwestern Amazonia, a diurnal feature observed previously by many investigators. Analysis is based on satellite, radar, sounding, and profiler observations of precipitating systems and cloudiness from the Tropical Rainfall Measuring Mission Large-Scale Biosphere-Atmosphere (TRMM-LBA) and the coincident Wet-Season Atmospheric Mesoscale Campaign (WETAMC) field programs during the early 1999 wet season. The general finding is that following the collapse of the nearly ubiquitous and locally generated afternoon ("noon balloon'') convection, organized deep convection contributes to a postmidnight maximum in raining area and high cloudiness, and to a lesser extent rainfall. Nocturnal convective systems have the effect of weakening and delaying the onset of the following afternoon's convection. Many of these nocturnal convective events are traced to large-scale squall lines, which propagate westward thousands of kilometers from their point of origin along the northeast coast of Brazil. In addition, a previously undescribed nocturnal stratiform drizzle phenomenon, generated above the melting layer independently from deep convection, contributes significantly to nocturnal cloud cover. Results from this study underscore the complex influence of propagating large-scale organized convection in locally modulating the diurnal variation in clouds and rain. The greatest significance of the nocturnal drizzle may be the potential effect on the diurnal radiation budget by the extensive midlevel nocturnal clouds rather than their marginal contribution to nocturnal rainfall. | |||||
BibTeX:
@article{rickenbach_nocturnal_2004, author = {Rickenbach, T. M.}, title = {Nocturnal cloud systems and the diurnal variation of clouds and rainfall in southwestern Amazonia}, journal = {Monthly Weather Review}, year = {2004}, volume = {132}, number = {5}, pages = {1201--1219}, url = {://WOS:000221195200010}, doi = {https://doi.org/10.1175/1520-0493(2004)132%3C1201:ncsatd%3E2.0.co;2} } |
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Richey, J.E., Melack, J.M., Aufdenkampe, A.K., Ballester, V.M. and Hess, L.L. | Outgassing from Amazonian rivers and wetlands as a large tropical source of atmospheric CO2 | 2002 | Nature Vol. 416(6881), pp. 617-620 |
article | DOI URL |
Abstract: Terrestrial ecosystems in the humid tropics play a potentially important but presently ambiguous role in the global carbon cycle. Whereas global estimates of atmospheric CO2 exchange indicate that the tropics are near equilibrium or are a source with respect to carbon(1,2), ground-based estimates indicate that the amount of carbon that is being absorbed by mature rainforests is similar to or greater than that being released by tropical deforestation(3,4) (about 1.6 Gt Cyr(-1)). Estimates of the magnitude of carbon sequestration are uncertain, however, depending on whether they are derived from measurements of gas fluxes above forests(5,6) or of biomass accumulation in vegetation and soils(3,7). It is also possible that methodological errors may overestimate rates of carbon uptake or that other loss processes have yet to be identified(3). Here we demonstrate that outgassing (evasion) of CO2 from rivers and wetlands of the central Amazon basin constitutes an important carbon loss process, equal to 1.2 +/- 0.3 Mg Cha(-1) yr(-1). This carbon probably originates from organic matter transported from upland and flooded forests, which is then respired and outgassed downstream. Extrapolated across the entire basin, this flux-at 0.5 Gt Cyr(-1) -is an order of magnitude greater than fluvial export of organic carbon to the ocean(8). From these findings, we suggest that the overall carbon budget of rainforests, summed across terrestrial and aquatic environments, appears closer to being in balance than would be inferred from studies of uplands alone(3,5-6). | |||||
BibTeX:
@article{richey_outgassing_2002, author = {Richey, J. E. and Melack, J. M. and Aufdenkampe, A. K. and Ballester, V. M. and Hess, L. L.}, title = {Outgassing from Amazonian rivers and wetlands as a large tropical source of atmospheric CO2}, journal = {Nature}, year = {2002}, volume = {416}, number = {6881}, pages = {617--620}, note = {Edition: 2002/04/12}, url = {://WOS:000174901900038}, doi = {https://doi.org/10.1038/416617a} } |
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Richey, J.E., Krusche, A.V., Johnson, M.S., da Cunha, H.B. and Ballester, M.V. | The role of rivers in the regional carbon balance [BibTeX] |
2009 | Vol. 186Amazonia and Global Change, pp. 489-504 |
incollection | DOI |
BibTeX:
@incollection{al_role_2009, author = {Richey, J. E. and Krusche, A. V. and Johnson, M. S. and da Cunha, H. B. and Ballester, M. V.}, title = {The role of rivers in the regional carbon balance}, booktitle = {Amazonia and Global Change}, publisher = {AGU}, year = {2009}, volume = {186}, pages = {489--504}, doi = {https://doi.org/10.1029/2008GM000734} } |
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Richey, J.E., Ballester, M.V., Davidson, E.A., Johnson, M.S. and Krusche, A.V. | Land-Water interactions in the amazon | 2011 | Biogeochemistry Vol. 105(1-3), pp. 1-5 |
article | DOI URL |
Abstract: Biogeochemistry is hosting this special thematic issue devoted to studies of land-water interactions, as part of the Large-scale Biosphere-Atmosphere Experiment in Amaznia (LBA). This compilation of papers covers a broad range of topics with a common theme of coupling land and water processes, across pristine and impacted systems. Findings highlighted that hydrologic flowpaths are clearly important across basin size and structure in determining how water and solutes reach streams. Land-use changes have pronounced impacts on flowpaths, and subsequently, on stream chemistry, from small streams to large rivers. Carbon is produced and transformed across a broad array of fluvial environments and wetlands. Surface waters are not only driven by, but provide feedback to, the atmosphere. | |||||
BibTeX:
@article{richey_land-water_2011, author = {Richey, Jeffrey E. and Ballester, Maria Victoria and Davidson, Eric A. and Johnson, Mark S. and Krusche, Alex V.}, title = {Land-Water interactions in the amazon}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {1--5}, url = {://WOS:000294501100001}, doi = {https://doi.org/10.1007/s10533-011-9622-y} } |
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Rice, A.H., Pyle, E.H., Saleska, S.R., Hutyra, L., Palace, M., Keller, M., de Camargo, P.B., Portilho, K., Marques, D.F. and Wofsy, S.C. | Carbon balance and vegetation dynamics in an old-growth Amazonian forest | 2004 | Ecological Applications Vol. 14(4), pp. S55-S71 |
article | DOI URL |
Abstract: Amazon forests could be globally significant sinks or sources for atmospheric carbon dioxide, but carbon balance of these forests remains poorly quantified. We surveyed 19.75 ha along four I-km transects of well-drained old-growth upland forest in the Tapajos National Forest near Santarem, Para, Brazil (2degrees51' S, 54degrees58' W) in order to assess carbon pool sizes, fluxes, and climatic controls on carbon balance. In 1999 there were, on average, 470 live trees per hectare with diameter at breast height (dbh) 10 cm. The mean (and 95% CI) aboveground live biomass was 143.7 +/- 5.4 Mg C/ha, with an additional 48.0 +/- 5.2 Mg C/ha of coarse woody debris (CWD). The increase of live wood biomass after two years was 1.40 +/- 0.62 Mg C(.)ha(-1.)yr(-1), the net result of growth (3.18 +/- 0.20 Mg C(.)ha(-1.)yr(-1) from mean bole increment of 0.36 cm/yr), recruitment of new trees (0.63 +/- 0.09 Mg C(.)ha(-1.)yr(-1), reflecting a. notably high stem recruitment rate of 4.8 +/- 0.9%), and mortality (-2.41 +/- 0.53 Mg C(.)ha(-1.)yr(-1) from stem death of 1.7% yr(-1)). The gain in live wood biomass was exceeded by respiration losses from CWD, resulting in an overall estimated net loss from total aboveground biomass of 1.9 +/- 1.0 Mg C(.)ha(-1.)yr(-1). The presence of large CWD pools, high recruitment rate, and net accumulation of small-tree biomass, suggest that a period of high mortality preceded the initiation of this study, possibly triggered by the strong El Nino Southern Oscillation events of the 1990s. Transfer of carbon between live and dead biomass pools appears to have led to substantial increases in the pool of CWD, causing the observed net carbon release. The data show that biometric studies of tropical forests neglecting CWD are unlikely to accurately determine carbon balance. Furthermore, the hypothesized sequestration flux from CO2 fertilization (textless0.5 Mg C(.)ha(-1.)yr(-1)) would be comparatively small and masked for considerable periods by climate-driven shifts in forest structure and associated carbon balance in tropical forests. | |||||
BibTeX:
@article{rice_carbon_2004, author = {Rice, A. H. and Pyle, E. H. and Saleska, S. R. and Hutyra, L. and Palace, M. and Keller, M. and de Camargo, P. B. and Portilho, K. and Marques, D. F. and Wofsy, S. C.}, title = {Carbon balance and vegetation dynamics in an old-growth Amazonian forest}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S55--S71}, url = {://WOS:000223269000007 http://www.esajournals.org/doi/pdf/10.1890/02-6006}, doi = {https://doi.org/10.1890/02-6006} } |
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Ribeiro, I.O., de Souza, R.A.F., Andreoli, R.V., Kayano, M.T. and Costa, P.d.S. | Spatiotemporal variability of methane over the Amazon from satellite observations [BibTeX] |
2016 | Advances in Atmospheric Sciences Vol. 33, pp. 852-864 |
article | |
BibTeX:
@article{ribeiro_spatiotemporal_2016, author = {Ribeiro, Igor Oliveira and de Souza, Rodrigo Augusto Ferreira and Andreoli, Rita Valéria and Kayano, Mary Toshie and Costa, Patrícia dos Santos}, title = {Spatiotemporal variability of methane over the Amazon from satellite observations}, journal = {Advances in Atmospheric Sciences}, year = {2016}, volume = {33}, pages = {852--864} } |
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Ribeiro, I.O., Andreoli, R.V., Kayano, M.T., Sousa, T.d., Medeiros, A.S., Guimarães, P.C., Barbosa, C.G., Godoi, R.H., Martin, S.T. and Souza, R.A.F.d. | Impact of the biomass burning on methane variability during dry years in the Amazon measured from an aircraft and the AIRS sensor [BibTeX] |
2018 | Science of the Total Environment Vol. 624, pp. 509-516 |
article | |
BibTeX:
@article{ribeiro_impact_2018, author = {Ribeiro, I. O. and Andreoli, R. V. and Kayano, M. T. and Sousa, T.R. de and Medeiros, A. S. and Guimarães, P. C. and Barbosa, C. G.G. and Godoi, R. H.M. and Martin, S. T. and Souza, R. A. F. de}, title = {Impact of the biomass burning on methane variability during dry years in the Amazon measured from an aircraft and the AIRS sensor}, journal = {Science of the Total Environment}, year = {2018}, volume = {624}, pages = {509--516} } |
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Ribeiro, G., Chambers, J.Q., Peterson, C., Trumbore, S., Magnabosco Marra, D., Wirth, C., Cannon, J., Négron-Juárez, R., Lima, A., Paula, E.d., Santos, J. and Higuchi, N. | Mechanical vulnerability and resistance to snapping and uprooting for Central Amazon tree species [BibTeX] |
2016 | Forest Ecology and Management Vol. 380, pp. 1-10 |
article | |
BibTeX:
@article{ribeiro_mechanical_2016, author = {Ribeiro, G.H.P.M. and Chambers, J. Q. and Peterson, C.J. and Trumbore, S.E. and Magnabosco Marra, D. and Wirth, C. and Cannon, J.B. and Négron-Juárez, R.I. and Lima, A.J.N. and Paula, E.V.C.M. de and Santos, J. and Higuchi, N.}, title = {Mechanical vulnerability and resistance to snapping and uprooting for Central Amazon tree species}, journal = {Forest Ecology and Management}, year = {2016}, volume = {380}, pages = {1--10} } |
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Ribeiro, A. and Castro, E. | Lei sobre gestão de florestas públicas e impactos na BR-163 [BibTeX] |
2008 | Vol. 1Sociedade, Território e Conflitos: BR-163 em questão, pp. 189-222 |
incollection | |
BibTeX:
@incollection{castro_lei_2008, author = {Ribeiro, A.C. and Castro, E.}, title = {Lei sobre gestão de florestas públicas e impactos na BR-163}, booktitle = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, pages = {189--222} } |
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Restrepo-Coupe, N.M., Christoffersen, B.O., Albert, L.P., Wu, J., Costa, M.H., Galbraith, D., Imbuzeiro, H., Martins, G., Da Araujo, A.C., Malhi, Y.S., Zeng, X., Moorcroft, P., Saleska Scott R., N. and Levine | Do dynamic global vegetation models capture the seasonality of carbon fluxes in the Amazon basin? A data-model intercomparison [BibTeX] |
2017 | Global Change Biology Vol. 191–208, pp. 1365 |
article | DOI |
BibTeX:
@article{restrepo-coupe_dynamic_2017, author = {Restrepo-Coupe, Naomi M. ; Christoffersen, Bradley O. ; Albert, Loren P. ; Wu, Jin ; Costa, Marcos H. ; Galbraith, David ; Imbuzeiro, Hewlley ; Martins, Giordane ; Da Araujo, Alessandro C. ; Malhi, Yadvinder S. ; Zeng, Xubin ; Moorcroft, Paul ; Saleska, Scott R., Natalia ; Levine}, title = {Do dynamic global vegetation models capture the seasonality of carbon fluxes in the Amazon basin? A data-model intercomparison}, journal = {Global Change Biology}, year = {2017}, volume = {191–208}, pages = {1365}, doi = {https://doi.org/10.1111/gcb.13442} } |
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Restrepo-Coupe, N., da Rocha, H., Hutyra, L., Araujo, A., Borma, L., Christoffersen, B., Cabral, O.d., Camargo, P., Cardoso, F.L., da Costa, A.L., Fitzjarrald, D., Goulden, M., Kruijt, B., Maia, J., Malhi, Y., Manzi, A., Miller, S., Nobre, A.D., von Randow, C., L.D.A., SÁ, Sakai, R., Tota, J., Wofsy, S., Zanchi, F. and al. , e. | What drives the seasonality of photosynthesis across the Amazon basin? A cross-site analysis of eddy flux tower measurements from the Brasil flux network [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183, pp. 128-144 |
article | |
BibTeX:
@article{restrepo-coupe_what_2013, author = {Restrepo-Coupe, N. and da Rocha, H. and Hutyra, L.R. and Araujo, A.C. and Borma, L.S.C. and Christoffersen, B.J. and Cabral, O.M.R. de and Camargo, P.B. and Cardoso, F. L. and da Costa, A.C. Lola and Fitzjarrald, D. and Goulden, M.L. and Kruijt, B. and Maia, J.M.F. and Malhi, Y.S. and Manzi, A.O. and Miller, S.D. and Nobre, A. D. and von Randow, C. and SÁ, L.D.A. and Sakai, R.K. and Tota, J. and Wofsy, S.C. and Zanchi, F.B. and al., et}, title = {What drives the seasonality of photosynthesis across the Amazon basin? A cross-site analysis of eddy flux tower measurements from the Brasil flux network}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, pages = {128--144} } |
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Restrepo-Coupe, N., Campos, K., Alves, L., Longo, M., Wiedemann, K., Oliveira-Junior, R., Aragão, L., Christoffersen, B., Camargo, P., Figueira, A., Ferreira, M., Oliveira, R., Penha, D., Prohaska, N., de Araújo, A., Daube, B., Wofsy, S. and Saleska, S. | Contrasting Carbon Cycle Responses to Dry (2015 El Niño) and Wet (2008 La Niña) Extreme Events at an Amazon Tropical Forest [BibTeX] |
2023 | SSRN PRE PRINT Vol. PRE PRINT |
article | DOI |
BibTeX:
@article{restrepo-coupe_contrasting_2023, author = {Restrepo-Coupe, Natalia and Campos, Kleber and Alves, Luciana and Longo, Marcos and Wiedemann, Kenia and Oliveira-Junior, Raimundo and Aragão, Luiz and Christoffersen, Bradley and Camargo, Plinio and Figueira, Adelaine and Ferreira, Maurício and Oliveira, Rafael and Penha, Deliane and Prohaska, Neill and de Araújo, Alessandro and Daube, Bruce and Wofsy, Steven and Saleska, Scott}, title = {Contrasting Carbon Cycle Responses to Dry (2015 El Niño) and Wet (2008 La Niña) Extreme Events at an Amazon Tropical Forest}, journal = {SSRN PRE PRINT}, year = {2023}, volume = {PRE PRINT}, doi = {https://doi.org/10.2139/ssrn.4442514} } |
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Restrepo-Coupe, N., Albert, L.P., Longo, M., Baker, I., Levine, N.M., Mercado, L.M., da Araujo, A.C., Christoffersen, B.O., Costa, M.H., Fitzjarrald, D.R., Galbraith, D., Imbuzeiro, H., Malhi, Y., von Randow, C., Zeng, X., Moorcroft, P. and Saleska, S.R. | Understanding water and energy fluxes in the Amazonia: Lessons from an observation-model intercomparison | 2021 | Global Change Biology Vol. 27(9), pp. 1802-1819 |
article | DOI URL |
Abstract: Abstract Tropical forests are an important part of global water and energy cycles, but the mechanisms that drive seasonality of their land-atmosphere exchanges have proven challenging to capture in models. Here, we (1) report the seasonality of fluxes of latent heat (LE), sensible heat (H), and outgoing short and longwave radiation at four diverse tropical forest sites across Amazonia—along the equator from the Caxiuanã and Tapajós National Forests in the eastern Amazon to a forest near Manaus, and from the equatorial zone to the southern forest in Reserva Jaru; (2) investigate how vegetation and climate influence these fluxes; and (3) evaluate land surface model performance by comparing simulations to observations. We found that previously identified failure of models to capture observed dry-season increases in evapotranspiration (ET) was associated with model overestimations of (1) magnitude and seasonality of Bowen ratios (relative to aseasonal observations in which sensible was only 20%–30% of the latent heat flux) indicating model exaggerated water limitation, (2) canopy emissivity and reflectance (albedo was only 10%–15% of incoming solar radiation, compared to 0.15%–0.22% simulated), and (3) vegetation temperatures (due to underestimation of dry-season ET and associated cooling). These partially compensating model-observation discrepancies (e.g., higher temperatures expected from excess Bowen ratios were partially ameliorated by brighter leaves and more interception/evaporation) significantly biased seasonal model estimates of net radiation (Rn), the key driver of water and energy fluxes (LE textasciitilde 0.6 Rn and H textasciitilde 0.15 Rn), though these biases varied among sites and models. A better representation of energy-related parameters associated with dynamic phenology (e.g., leaf optical properties, canopy interception, and skin temperature) could improve simulations and benchmarking of current vegetation–atmosphere exchange and reduce uncertainty of regional and global biogeochemical models. | |||||
BibTeX:
@article{restrepo-coupe_understanding_2021, author = {Restrepo-Coupe, Natalia and Albert, Loren P. and Longo, Marcos and Baker, Ian and Levine, Naomi M. and Mercado, Lina M. and da Araujo, Alessandro C. and Christoffersen, Bradley O'Donnell and Costa, Marcos H. and Fitzjarrald, David R. and Galbraith, David and Imbuzeiro, Hewlley and Malhi, Yadvinder and von Randow, Celso and Zeng, Xubin and Moorcroft, Paul and Saleska, Scott R.}, title = {Understanding water and energy fluxes in the Amazonia: Lessons from an observation-model intercomparison}, journal = {Global Change Biology}, year = {2021}, volume = {27}, number = {9}, pages = {1802--1819}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.15555}, doi = {https://doi.org/10.1111/gcb.15555} } |
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Restom, T.G. and Nepstad, D.C. | Seedling growth dynamics of a deeply rooting liana in a secondary forest in eastern Amazonia | 2004 | Forest Ecology and Management Vol. 190(1), pp. 109-118 |
article | DOI URL |
Abstract: Root penetration rate was estimated for the liana Davilla kunthii St. Hill (Dilleniaceae) in a secondary forest in eastern Amazonia by relating aboveground growth with root depth measurements. Basal diameter, height, number of leaves and number of scars of approximately 100 individuals were monitored between 1991 and 1996. These measurements were used to estimate the age of 28 seedlings (up to 137 cm, of height) that were excavated for root depth measurements, and a model was derived for estimating root penetration rate for D. kunthii at this site. The deepest individual excavated had roots as deep as 10 m and had a mean estimated age of 15 years. Root penetration rate was higher below 3 m depth than in more superficial soil, perhaps due to a decrease in soil resistance, with depth. Some individuals made use of less resistant soil, such as leaf-cutter ants' nests or the channels of dead roots, to increase their root depth. Pre-dawn leaf water potential, measured in 28 other individuals, was uniformly high in plants with a diameter greater than 12 mm, but highly variable in plants with a smaller diameter, indicating lower water deficit in more deeply rooting plants. Deep rooting was shown to be a priority in the development of D. kunthii and may contribute to its success in establishing in regenerating seasonal forests. Soil heterogeneity plays an important role in allowing for deeper root penetration, which may result in a reduction in the water deficit during the dry season. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{restom_seedling_2004, author = {Restom, T. G. and Nepstad, D. C.}, title = {Seedling growth dynamics of a deeply rooting liana in a secondary forest in eastern Amazonia}, journal = {Forest Ecology and Management}, year = {2004}, volume = {190}, number = {1}, pages = {109--118}, url = {://WOS:000220456000010}, doi = {https://doi.org/10.1016/j.foreco.2003.10.010} } |
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Restom, T.G. and Nepstad, D.C. | Contribution of vines to the evapotranspiration of a secondary forest in eastern Amazonia | 2001 | Plant and Soil Vol. 236(2), pp. 155-163 |
article | DOI URL |
Abstract: The contribution of vines to the evapotranspiration (ET) of a secondary forest in eastern Amazonia was estimated based on field measurements of vine and tree transpiration, and seasonal changes in soil water content to 12 meters depth. Transpiration of vines and trees was measured with sapflow gauges placed around stems or branches. Total ET of the secondary forest was estimated as the sum of rainfall and reductions in soil moisture measured using Time Domain Reflectometry sensors installed in the walls of soil shafts. Our results suggest that vines transpire more than trees with stems of similar diameter, and with similar leaf crown exposure to sunlight. Trees experienced a smaller reduction in transpiration from the wet to the dry season than did vines. During the dry season, vines represented 8% (0.4 mm d(-1)) of total secondary forest ET (5.4 mm d(-1)), but they represented only 5.5% (0.5 m(2) ha(-1)) of total secondary forest basal area (9.6 m(2) ha(-)1). Considering that transpiration corresponds to 66-90% of forest ET, vines may contribute 9-12% to the transpiration of the forest. Hence, vine cutting, which is a commonly recommended management practice to favor the growth of tropical timber trees, may result in a proportionally larger reduction in evapotranspiration than in forest basal area. | |||||
BibTeX:
@article{restom_contribution_2001, author = {Restom, T. G. and Nepstad, D. C.}, title = {Contribution of vines to the evapotranspiration of a secondary forest in eastern Amazonia}, journal = {Plant and Soil}, year = {2001}, volume = {236}, number = {2}, pages = {155--163}, url = {://WOS:000172168800004}, doi = {https://doi.org/10.1023/a:1012776532147} } |
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Resende, A.F.d., Jochen, S., Streher, A.S., Ferreira-Ferreira, J., FernandezPiedade, M.T. and Freire Silva, T.S. | Massive tree mortality from flood pulse disturbances in Amazonian floodplain forests: The collateral effects of hydropower production [BibTeX] |
2019 | Science of The Total Environment Vol. 659, pp. 587-598 |
article | |
BibTeX:
@article{resende_massive_2019, author = {Resende, Angélica Faria de and Jochen, Schöngart. and Streher, Annia Susin and Ferreira-Ferreira, Jefferson and FernandezPiedade, Maria Teresa and Freire Silva, Thiago Sanna}, title = {Massive tree mortality from flood pulse disturbances in Amazonian floodplain forests: The collateral effects of hydropower production}, journal = {Science of The Total Environment}, year = {2019}, volume = {659}, pages = {587--598} } |
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Resende, A.F., Piedade, M.T.F., Feitosa, Y.O., Andrade, V.H.F., Trumbore, S.E., Durgante, F.M., Macedo, M.O. and Schöngart, J. | Flood-pulse disturbances as a threat for long-living Amazonian trees | 2020 | New Phytologist Vol. 227(6), pp. 1790-1803 |
article | DOI URL |
Abstract: Summary The long-lived tree species Eschweilera tenuifolia (O. Berg) Miers is characteristic of oligotrophic Amazonian black-water floodplain forests (igapó), seasonally inundated up to 10 months per year, often forming monodominant stands. We investigated E. tenuifolia' growth and mortality patterns in undisturbed (Jaú National Park - JNP) and disturbed igapós (Uatumã Sustainable Development Reserve - USDR, downstream of the Balbina hydroelectric dam). We analysed age–diameter relationships, basal area increment (BAI) through 5-cm diameter classes, growth changes and growth ratios preceding death, BAI clustering, BAI ratio, and dated the individual year of death (14C). Growth and mortality patterns were then related to climatic or anthropogenic disturbances. Results were similar for both populations for estimated maximum ages (JNP, 466 yr; USDR, 498 yr, except for one USDR tree with an estimated age of 820 yr) and slightly different for mean diameter increment (JNP: 2.04 mm; USDR: 2.28 mm). Living trees from JNP showed altered growth post-1975 and sparse tree mortality occurred at various times, possibly induced by extreme hydroclimatic events. In contrast with the JNP, abrupt growth changes and massive mortality occurred in the USDR after the dam construction began (1983). Even more than 30 yr after dam construction, flood-pulse alteration continues to affect both growth and mortality of E. tenuifolia. Besides its vulnerability to anthropogenic disturbances, this species is also susceptible to long-lasting dry and wet periods induced by climatic events, the combination of both processes may cause its local and regional extinction. | |||||
BibTeX:
@article{resende_flood-pulse_2020, author = {Resende, Angélica F. and Piedade, Maria T. F. and Feitosa, Yuri O. and Andrade, Victor Hugo F. and Trumbore, Susan E. and Durgante, Flávia M. and Macedo, Maíra O. and Schöngart, Jochen}, title = {Flood-pulse disturbances as a threat for long-living Amazonian trees}, journal = {New Phytologist}, year = {2020}, volume = {227}, number = {6}, pages = {1790--1803}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.16665}, doi = {https://doi.org/10.1111/nph.16665} } |
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Renno, C.D., Nobre, A.D., Cuartas, L.A., Soares, J.V., Hodnett, M.G., Tomasella, J. and Waterloo, M.J. | HAND, a new terrain descriptor using SRTM-DEM: Mapping terra-firme rainforest environments in Amazonia | 2008 | Remote Sensing of Environment Vol. 112(9), pp. 3469-3481 |
article | DOI URL |
Abstract: Optical imagery can reveal spectral properties of forest canopy, which rarely allows for finding accurate correspondence of canopy features with soils and hydrology. In Amazonia non-floodable swampy forests call not be easily distinguished from non-floodable terra-firme forests using just bidimensional spectral data. accurate topographic data are required for the understanding of land Surface processes at finer scales, Topographic detail has now become available with the Shuttle Radar Topographic Mission (SRTM) data. This new digital elevation model (DEM) shows the feature-rich relief of lowland rain forests, adding to the ability to map rain forest environments through many quantitative terrain descriptors. In this paper we report oil the development of a new quantitative topographic algorithm, called HAND (Height Above the Nearest Drainage), based oil SRTM-DEM data. We tested the HAND descriptor for a groundwater, topographic and vegetation dataset from central Amazonia. The application of the HAND descriptor in terrain classification revealed strong correlation between soil water conditions, like classes of water table depth, and topography. This correlation obeys the physical principle of soil draining potential, or relative vertical distance to drainage, which call be detected remotely through the topography of the vegetation canopy found in the SRTM-DEM data. (C) 2008 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{renno_hand_2008, author = {Renno, Camilo Daleles and Nobre, Antonio Donato and Cuartas, Luz Adriana and Soares, Joao Vianei and Hodnett, Martin G. and Tomasella, Javier and Waterloo, Maarten J.}, title = {HAND, a new terrain descriptor using SRTM-DEM: Mapping terra-firme rainforest environments in Amazonia}, journal = {Remote Sensing of Environment}, year = {2008}, volume = {112}, number = {9}, pages = {3469--3481}, url = {://WOS:000258784700001}, doi = {https://doi.org/10.1016/j.rse.2008.03.018} } |
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Renck, A. and Lehmann, J. | Rapid water flow and transport of inorganic and organic nitrogen in a highly aggregated tropical soil | 2004 | Soil Science Vol. 169(5), pp. 330-341 |
article | DOI URL |
Abstract: Microaggregated tropical soils have shown high water conductivity even under unsaturated conditions in laboratory experiments. It is not clear, however, what depth the infiltrating soil water reaches during storm events under humid tropical conditions and how this relates to losses of N by leaching. Dynamics and fluxes of water and. applied N-15 were determined with high temporal resolution to a depth of 5 m in a Xanthic Hapludox of central Amazonia, Brazil. The soil water percolated to a depth of 0.9 m within 2 h of a rainfall event of 48 mm. Water fluxes were significantly slower below 0.9 m (17% of infiltration at 0-0.9 m) due to higher bulk densities. Percolation not only started rapidly after a rainfall event when soil water suction reached a certain threshold (ca. 20-30 hPa) but was also reduced to background levels less than 1 h after the rain had ended. Traces of labeled N reached 5 in within a few days, and N-15 maintained high levels to a depth of 1.2 m throughout the rainy season. Organic N was a large proportion (36-44%) of the total N leaching and the proportion increased with depth. However, organic N percolated more slowly than nitrate. The demonstrated extreme short-term dynamics of water fluxes have implications for measurement design of water availability and solute leaching in microaggregated tropical soil that require correct time integrals of solution concentrations and soil water dynamics. Measurement intervals of 30 min or less were necessary in our study. Rapid water flows explain the observed high N losses from the topsoil of microaggregated tropical soil and the large nitrate accumulation in the deep soil to a depth of at least 5 m. | |||||
BibTeX:
@article{renck_rapid_2004, author = {Renck, A. and Lehmann, J.}, title = {Rapid water flow and transport of inorganic and organic nitrogen in a highly aggregated tropical soil}, journal = {Soil Science}, year = {2004}, volume = {169}, number = {5}, pages = {330--341}, url = {://WOS:000221494900002}, doi = {https://doi.org/10.1097/01.ss.0000128016.00021.3d} } |
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Remington, S., Strahm, B., Neu, V., Richey, J. and Cunha, H.d. | The role of sorption in control of riverine dissolved organic carbon concentrations by riparian zone soils in the Amazon Basin [BibTeX] |
2007 | Soil Science Vol. 172(4), pp. 279-291 |
article | |
BibTeX:
@article{remington_role_2007, author = {Remington, S.M. and Strahm, B.D. and Neu, V. and Richey, J.E. and Cunha, H.B. da}, title = {The role of sorption in control of riverine dissolved organic carbon concentrations by riparian zone soils in the Amazon Basin}, journal = {Soil Science}, year = {2007}, volume = {172}, number = {4}, pages = {279--291} } |
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Remington, S., Krusche, A. and Richey, J. | Effects of DOM photochemistry on bacterial metabolism and CO2 evasion during falling water in a humic and a whitewater river in the Brazilian Amazon | 2011 | Biogeochemistry Vol. 105(1-3), pp. 185-200 |
article | DOI URL |
Abstract: In the Amazon river system, the source of the large quantity of CO(2) evading from river surfaces remains unidentified. Photochemical transformation of dissolved organic matter (DOM) into dissolved inorganic carbon (DIC) and low molecular weight organic acids (LMWOAs) is a promising candidate. Few studies in the Amazon river system, and river systems in general, have attempted to quantify the contribution of these specific photoproducts to CO(2) evasion. We conducted photochemical degradation and (14)C addition experiments to measure the rate of production and the impact on bacterial metabolism, respectively, in the black water Rio Negro and in the white water Rio Solimes during low water. We found statistically significant production of both photoproducts in the Rio Negro and none in Rio Solimes. We also found that two photochemically produced LMWOAs-acetic and formic acid-may play a significant role in bacterial metabolism in both rivers. Based on our experimental results, we estimate that photochemically produced CO(2), acetic acid and formic acid alone contribute to only 0.5% of the CO(2) evading from the Rio Negro. Due to our experimental set-up, analytical methods and time of sampling, we caution that our estimate is very conservative. More extensive research is needed before drawing conclusions on the contribution of photochemistry to CO(2) evasion from river surfaces of the Amazon basin. | |||||
BibTeX:
@article{remington_effects_2011, author = {Remington, Sonya and Krusche, Alex and Richey, Jeff}, title = {Effects of DOM photochemistry on bacterial metabolism and CO2 evasion during falling water in a humic and a whitewater river in the Brazilian Amazon}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {185--200}, url = {://WOS:000294501100014}, doi = {https://doi.org/10.1007/s10533-010-9565-8} } |
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Reichert, T., Rammig, A., Fuchslueger, L., Lugli, L.F., Quesada, C.A. and Fleischer, K. | Plant phosphorus-use and -acquisition strategies in Amazonia | 2022 | New Phytologist Vol. 234(4), pp. 1126-1143 |
article | DOI URL |
Abstract: Summary In the tropical rainforest of Amazonia, phosphorus (P) is one of the main nutrients controlling forest dynamics, but its effects on the future of the forest biomass carbon (C) storage under elevated atmospheric CO2 concentrations remain uncertain. Soils in vast areas of Amazonia are P-impoverished, and little is known about the variation or plasticity in plant P-use and -acquisition strategies across space and time, hampering the accuracy of projections in vegetation models. Here, we synthesize current knowledge of leaf P resorption, fine-root P foraging, arbuscular mycorrhizal symbioses, and root acid phosphatase and organic acid exudation and discuss how these strategies vary with soil P concentrations and in response to elevated atmospheric CO2. We identify knowledge gaps and suggest ways forward to fill those gaps. Additionally, we propose a conceptual framework for the variations in plant P-use and -acquisition strategies along soil P gradients of Amazonia. We suggest that in soils with intermediate to high P concentrations, at the plant community level, investments are primarily directed to P foraging strategies via roots and arbuscular mycorrhizas, whereas in soils with intermediate to low P concentrations, investments shift to prioritize leaf P resorption and mining strategies via phosphatases and organic acids. | |||||
BibTeX:
@article{reichert_plant_2022, author = {Reichert, Tatiana and Rammig, Anja and Fuchslueger, Lucia and Lugli, Laynara F. and Quesada, Carlos A. and Fleischer, Katrin}, title = {Plant phosphorus-use and -acquisition strategies in Amazonia}, journal = {New Phytologist}, year = {2022}, volume = {234}, number = {4}, pages = {1126--1143}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.17985}, doi = {https://doi.org/10.1111/nph.17985} } |
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Rehbein, A., Ambrizzi, T. and Mechoso, C.R. | Mesoscale convective systems over the Amazon basin. Part I: climatological aspects [BibTeX] |
2018 | International Journal of Climatology Vol. 38(1), pp. 215-229 |
article | |
BibTeX:
@article{rehbein_mesoscale_2018, author = {Rehbein, A. and Ambrizzi, T. and Mechoso, C. R.}, title = {Mesoscale convective systems over the Amazon basin. Part I: climatological aspects}, journal = {International Journal of Climatology}, year = {2018}, volume = {38}, number = {1}, pages = {215--229} } |
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Reddington, C., Spracklen, D., Artaxo, P., Ridley, D., Rizzo, L. and Arana, A. | Analysis of particulate emissions from tropical biomass burning using a global aerosol model and long-term surface observations [BibTeX] |
2016 | Atmos. Chem. Phys. | article | DOI |
BibTeX:
@article{reddington_analysis_2016, author = {Reddington, C.L. and Spracklen, D.V. and Artaxo, P. and Ridley, D. and Rizzo, L.V. and Arana, A.}, title = {Analysis of particulate emissions from tropical biomass burning using a global aerosol model and long-term surface observations}, journal = {Atmos. Chem. Phys.}, year = {2016}, note = {Edition: http://www.atmos-chem-phys-discuss.net/acp-2015-967/acp-2015-967.pdf}, doi = {https://doi.org/10.5194/acp-2015-967} } |
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Reddington, C.L., Butt, E., Ridley, D., Artaxo, P., Morgan, W., Coe, H. and Spracklen, D. | Air quality and human health improvements from reductions in deforestation-related fire in Brazil [BibTeX] |
2015 | Nature Geoscience Vol. 8, pp. 768-771 |
article | DOI |
BibTeX:
@article{reddington_air_2015, author = {Reddington, C. L. and Butt, E.W. and Ridley, D.A. and Artaxo, P. and Morgan, W.T. and Coe, H. and Spracklen, D.V.}, title = {Air quality and human health improvements from reductions in deforestation-related fire in Brazil}, journal = {Nature Geoscience}, year = {2015}, volume = {8}, pages = {768--771}, doi = {https://doi.org/10.1038/NGEO2535} } |
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Reddington Morgan, W.T.D.E.B.J.C.H.A.P.S.C.E.M.J.and.S.D.V.C.L. | Biomass burning aerosol over the Amazon: analysis of aircraft, surface and satellite observations using a global aerosol model [BibTeX] |
2019 | Atmos. Chem. Phys. Vol. 19, pp. 9125-9152 |
article | DOI |
BibTeX:
@article{reddington_biomass_2019, author = {Reddington, Morgan, W. T., Darbyshire, E., Brito, J., Coe, H., Artaxo, P., Scott, C. E., Marsham, J., and Spracklen, D. V., C. L.}, title = {Biomass burning aerosol over the Amazon: analysis of aircraft, surface and satellite observations using a global aerosol model}, journal = {Atmos. Chem. Phys.}, year = {2019}, volume = {19}, pages = {9125--9152}, doi = {https://doi.org/10.5194/acp-19-9125-2019} } |
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Rebêlo, A.G.d.M., Monteiro, M.T.F., Ferreira, S.J.F., Villamizar, E.A.R., Sargentini Junior, É., Bolson, M.A. and Duvoisin Junior, S. | Biogeoquimica Espaço-Temporal da Liteira em Ambiente de Floresta Natural na Amazônia Central [BibTeX] |
2021 | Quim. Nova Vol. 44(10), pp. 1252-1260 |
article | |
BibTeX:
@article{rebelo_biogeoquimica_2021, author = {Rebêlo, Ananda Gabrielle de Matos and Monteiro, Maria Terezinha Ferreira and Ferreira, Sávio José Filgueiras and Villamizar, Eduardo Antonio Ríos and Sargentini Junior, Ézio and Bolson, Marcos Alexandre and Duvoisin Junior, Sergio}, title = {Biogeoquimica Espaço-Temporal da Liteira em Ambiente de Floresta Natural na Amazônia Central}, journal = {Quim. Nova}, year = {2021}, volume = {44}, number = {10}, pages = {1252--1260} } |
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Read, J.M., Clark, D.B., Venticinque, E.M. and Moreira, M.P. | Application of merged 1-m and 4-m resolution satellite data to research and management in tropical forests | 2003 | Journal of Applied Ecology Vol. 40(3), pp. 592-600 |
article | DOI URL |
Abstract: 1. Until very recently there have been no digital data from satellites for studying events that occur at scales of 10-1000 m(2) over large areas (100-100 000 ha). Many phenomena of interest to ecologists, such as impacts of selective logging on forest processes, occur over large extents but at local scales. Here we report results from a pilot project to evaluate through visual interpretation the potential of newly available 1-m panchromatic and 4-m multi-spectral data from the IKONOS satellite, for studying forest structure, dynamics and logging impacts in logged and old-growth tropical moist forest. 2. The study area, the Mil Madeireira Itacoatiara Ltda site of Precious Woods Amazon, near Itacoatiara, Amazonas, Brazil, is managed using reduced-impact logging practices to minimize environmental impacts, and thus represents a lower bound for logging impacts in tropical rain forests. 3. The IKONOS image was georeferenced using uncorrected global positioning system (GPS) locations for 10 control trees whose crowns were clearly visible in the image. The root mean square error (RMSE) of the geometric transformation was 4 m, while the mean crown diameter of 50 randomly chosen trees in old-growth forest was 9.4 m. The fact that the RMSE was less than half the average crown diameter implies that it will usually be possible to locate from the ground crowns that are distinct on the image, given sufficiently accurate GPS locations. 4. IKONOS data are well suited for evaluating and monitoring logging impacts. Many impacts of logging were clearly observable in the image, including major and some minor roads, logging patios and larger logging gaps. Smaller extraction roads and logging gaps were not observable. 5. Many individual trees were distinct on the IKONOS image, indicating that it is now feasible to conduct demographic studies of tropical rain forest canopy trees based on repeated satellite observations. Linking these remotely sensed data to ground data will require improved GPS positions, because it is currently difficult to obtain accurate GPS readings in tropical rain forest understoreys. 6. Synthesis and applications. IKONOS 1-m and 4-m data were found to be useful for identifying individual trees as well as some logging management features in a tropical moist forest in central Amazonia. These data will have many applications for research and management of intervened and old-growth tropical forests, including planning and assessment of logging activities, as well as monitoring adherence to certification criteria such as those of the Forest Stewardship Council. Rapid development of these applications will come from building on existing data on forest structure and function, and by fostering collaborations between remote sensing scientists, ecologists and natural resource managers. | |||||
BibTeX:
@article{read_application_2003, author = {Read, J. M. and Clark, D. B. and Venticinque, E. M. and Moreira, M. P.}, title = {Application of merged 1-m and 4-m resolution satellite data to research and management in tropical forests}, journal = {Journal of Applied Ecology}, year = {2003}, volume = {40}, number = {3}, pages = {592--600}, url = {://WOS:000183283400015 http://onlinelibrary.wiley.com/store/10.1046/j.1365-2664.2003.00814.x/asset/j.1365-2664.2003.00814.x.pdf?v=1&t=h6hwkggt&s=e443d6353b046eff6ff6e379609ba5c9e7f5ebdf}, doi = {https://doi.org/10.1046/j.1365-2664.2003.00814.x} } |
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Ray, D., Nepstad, D. and Moutinho, P. | Micrometeorological and canopy controls of fire susceptibility in a forested Amazon landscape | 2005 | Ecological Applications Vol. 15(5), pp. 1664-1678 |
article | DOI URL |
Abstract: Fire is playing an increasing role in shaping the structure, composition, and function of vast areas of moist tropical forest. Within the Brazilian Amazon, cattle ranching and swidden agriculture provide abundant sources of ignition to forests that become susceptible to fire through selective logging, severe drought and, perhaps, fragmentation. Our understanding of the biophysical factors that control fire spread through Amazon forests remains largely anecdotal, however, restricting our ability to model the Amazon fire regime, and to simulate the effects of trends in climate and land-use activities on future regimes. We used experimental fires together with measurements of micrometeorology (rainfall, vapor pressure deficit [VPD], wind velocity), canopy attributes (leaf area index [LAI], canopy height), and fuel characteristics (litter moisture content [LMC] and mass) to identify the variables most closely associated with fire susceptibility in the east-central Amazon. Fire spread rates (FSR, m/min) were measured in three common forest types: an 8-yr-old regrowth forest, a recently logged/burned forest, and a mature forest. One hundred fires were set in each study area during the last two months of the 2002 dry season. VPD, recent precipitation history, wind velocity, and LAI explained 57% of the variability in FSR. In combination, LAI, canopy height, and recent precipitation history accounted for similar to 65% of the-variability in VPD, the single most important predictor of FSR, and approximately half of the total observed variability in FSR. Using logistic regression we were able to predict whether a fire would spread or die 72% of the time based on LAI, canopy height, and recent precipitation history. An approximate threshold in fire susceptibility was associated with a LMC of similar to 23%, somewhat higher than previously reported (15%). Fire susceptibility was highest under low, sparse canopies, which permitted greater coupling of relatively hot, dry air above the canopy with the otherwise cool, moist air near the forest floor. Fire susceptibility increased over time after rain events as the forest floor gradually dried. The most important determinants of fire susceptibility can be captured in ecosystem and climate models and through remotely sensed estimates of canopy structure, canopy water content, and microclimatic variables. | |||||
BibTeX:
@article{ray_micrometeorological_2005, author = {Ray, D. and Nepstad, D. and Moutinho, P.}, title = {Micrometeorological and canopy controls of fire susceptibility in a forested Amazon landscape}, journal = {Ecological Applications}, year = {2005}, volume = {15}, number = {5}, pages = {1664--1678}, url = {://WOS:000232322600015}, doi = {https://doi.org/10.1890/05-0404} } |
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Ray, D., Nepstad, D. and Brando, P. | Predicting moisture dynamics of fine understory fuels in a moist tropical rainforest system: results of a pilot study undertaken to identify proxy variables useful for rating fire danger | 2010 | New Phytologist Vol. 187(3), pp. 720-732 |
article | DOI URL |
Abstract: PtextgreaterThe use of fire as a land management tool in the moist tropics often has the unintended consequence of degrading adjacent forest, particularly during severe droughts. Reliable models of fire danger are needed to help mitigate these impacts. Here, we studied the moisture dynamics of fine understory fuels in the east-central Brazilian Amazon during the 2003 dry season. Drying stations established under varying amounts of canopy cover (leaf area index (LAI) = 0 - 5.3) were subjected to a range of water inputs (5-15 mm) and models were developed to forecast litter moisture content (LMC). Predictions were then compared with independent field data. A multiple linear regression relating litter moisture content to forest structure (LAI), ambient vapor pressure deficit (VPD(M)) and an index of elapsed time since a precipitation event (d-1) was identified as the best-fit model (adjusted R2 = 0.89). Relative to the independent observations, model predictions were relatively unbiased when the LMC was textless 50%, but consistently underestimated the LMC when the observed values were higher. The approach to predicting fire danger based on forest structure and meteorological variables is promising; however, additional information to the LAI, for example forest biomass, may be required to accurately capture the influence of forest structure on understory microclimate. | |||||
BibTeX:
@article{ray_predicting_2010, author = {Ray, David and Nepstad, Dan and Brando, Paulo}, title = {Predicting moisture dynamics of fine understory fuels in a moist tropical rainforest system: results of a pilot study undertaken to identify proxy variables useful for rating fire danger}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {720--732}, note = {Edition: 2010/07/14}, url = {://WOS:000280122500016}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03358.x} } |
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Raupp, C.F.M. and Dias, P.L.S. | Excitation mechanism of mixed Rossby-gravity waves in the equatorial atmosphere: Role of the nonlinear interactions among equatorial waves | 2005 | Journal of the Atmospheric Sciences Vol. 62(5), pp. 1446-1462 |
article | DOI URL |
Abstract: One possible explanation for the relatively high signal of the mixed Rossby-gravity waves observed in the tropical atmosphere is explored in this paper. This explanation is based on the nonlinear interactions among equatorial waves, and is made by adopting the nonlinear shallow water equations on the equatorial 0 plane. These equations are solved by a spectral method that uses the eigensolutions of the linear problem as the expansion basis. Numerical simulations are performed with a specified stationary mass source representative of the tropospheric heating associated with the typical convective activity over the Amazon Basin during the austral summer period. The numerical results show that the mixed Rossby-gravity waves are excited by a nonlinear mechanism in which the slow modes excited by the thermal forcing generate a quasigeostrophic basic state that supplies energy especially to the mixed Rossby-gravity waves with zonal wavenumbers 4 and 5, which have periods of the order of 4 days. The phase propagation of these unstable mixed modes leads to a periodic energy exchange between the mixed Rossby-gravity waves and the quasigeostrophic modes (Rossby and ultralong Kelvin modes). This regular nonlinear energy exchange implies a 4-day-cycle vacillation in the solution, which might be linked to the 4-6-day local oscillations in the dynamical field data throughout the Amazon region found in observational studies. Besides the importance of quasigeostrophic modes in the excitation of mixed Rossby-gravity waves, the numerical results also suggest that the predominance of the slow modes is crucial for maintaining the high signal of the unstable mixed modes, since these waves are strongly suppressed by the inclusion of the fast modes in the integration. | |||||
BibTeX:
@article{raupp_excitation_2005, author = {Raupp, C. F. M. and Dias, P. L. S.}, title = {Excitation mechanism of mixed Rossby-gravity waves in the equatorial atmosphere: Role of the nonlinear interactions among equatorial waves}, journal = {Journal of the Atmospheric Sciences}, year = {2005}, volume = {62}, number = {5}, pages = {1446--1462}, url = {://WOS:000229335800010}, doi = {https://doi.org/10.1175/jas3412.1} } |
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Ratana, P., Huete, A. and Ferreira, L.G. | Analysis of cerrado physiognomies and conversion in the MODIS seasonal-temporal domain | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: The " cerrado" biome in central Brazil is rapidly being converted into pasture and agricultural crops with important consequences for local and regional climate change and regional carbon fluxes between the atmosphere and land surface. Satellite remote sensing provides an opportunity to monitor the highly diverse and complex cerrado biome, encompassing grassland, shrubland, woodland and gallery forests, and converted areas. In this study, the potential of Terra Moderate Resolution Imaging Spectroradiometer ( MODIS) data is analyzed to discriminate among these diverse cerrado physiognomies and converted pastures based on their seasonal dynamics and phenology. Four years ( 2000 - 03) of MODIS 16- day composited, 250- m resolution vegetation index ( VI) data were extracted over a series of biophysically sampled field study sites representing the major cerrado types. The temporal VI profiles over the cerrado formations exhibited high seasonal contrasts with a pronounced dry season from June to August and a wet growing season from November to March. The converted pasture areas showed the highest seasonal contrasts while the gallery forest formation had the lowest contrast. Seasonal VI variations were negatively correlated with woody canopy crown cover and provided a method to discriminate among converted cerrado areas, gallery forests, and the woody and herbaceous cerrado formations. The grassland and shrub cerrado formations, however, were difficult to separate based on their seasonal VI profiles. Maximum discrimination among the cerrado types occurred during the dry season where a positive linear relationship was found between VI and green cover. The annual integrated VI values showed the gallery forests and cerrado woodland as having the highest, and hence most annual productivity, while the more herbaceous shrub and grassland cerrado types were least productive. The cumulative VI profiles of converted cerrado, pasture areas varied distinctly in shape due to their strong dry season inactivity. Furthermore, the annual integrated VI values of the converted pastures differed significantly between the normalized difference vegetation index ( NDVI) and the enhanced vegetation index ( EVI) MODIS VI products, resulting in large discrepancies in productivity estimates relative to the native cerrado sites. This study shows that the MODIS seasonal - temporal VI profiles are highly useful in monitoring the cerrado biome and conversion- related activities. | |||||
BibTeX:
@article{ratana_analysis_2005, author = {Ratana, P. and Huete, A.R. and Ferreira, L. G.}, title = {Analysis of cerrado physiognomies and conversion in the MODIS seasonal-temporal domain}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241212000001} } |
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Rasera, M.d.F.F.L., Krusche, A.V., Richey, J.E., Ballester, M.V.R. and Victória, R.L. | Spatial and temporal variability of pCO2 and CO2 efflux in seven Amazonian Rivers [BibTeX] |
2013 | Biogeochemistry Vol. 116, pp. 241-259 |
article | DOI |
BibTeX:
@article{rasera_spatial_2013, author = {Rasera, Maria de Fátima F. L. and Krusche, Alex V. and Richey, Jeffrey E. and Ballester, Maria V. R. and Victória, Reynaldo L.}, title = {Spatial and temporal variability of pCO2 and CO2 efflux in seven Amazonian Rivers}, journal = {Biogeochemistry}, year = {2013}, volume = {116}, pages = {241--259}, doi = {https://doi.org/10.1007/s10533-013-9854-0} } |
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Rasera, M.d.F.F.L., Ballester, M.V.R., Krusche, A.V., Salimon, C., Montebelo, L.A., Alin, S.R., Victoria, R.L. and Richey, J.E. | Small rivers in the southwestern Amazon and their role in CO(2) outgassing | 2008 | Earth Interactions Vol. 12 |
article | DOI URL |
Abstract: A recent estimate of CO(2) outgassing from Amazonian wetlands suggests that an order of magnitude more CO(2) leaves rivers through gas exchange with the atmosphere than is exported to the ocean as organic plus inorganic carbon. However, the contribution of smaller rivers is still poorly understood, mainly because of limitations in mapping their spatial extent. Considering that the largest extension of the Amazon River network is composed of small rivers, the authors' objective was to elucidate their role in air-water CO(2) exchange by developing a geographic information system ( GIS)- based model to calculate the surface area covered by rivers with channels less than 100 m wide, combined with estimated CO(2) outgassing rates at the Ji-Parana River basin, in the western Amazon. Estimated CO(2) outgassing was the main carbon export pathway for this river basin, totaling 289 Gg C yr(-1), about 2.4 times the amount of carbon exported as dissolved inorganic carbon ( 121 Gg C yr(-1)) and 1.6 times the dissolved organic carbon export ( 185 Gg C yr(-1)). The relationships established here between drainage area and channel width provide a new model for determining small river surface area, allowing regional extrapolations of air - water gas exchange. Applying this model to the entire Amazon River network of channels less than 100 m wide ( third to fifth order), the authors calculate that the surface area of small rivers is 0.3 +/- 0.05 million km(2), and it is potentially evading to the atmosphere 170 +/- 42 Tg C yr(-1) as CO(2). Therefore, these ecosystems play an important role in the regional carbon balance. | |||||
BibTeX:
@article{rasera_small_2008, author = {Rasera, Maria de Fatima F. L. and Ballester, Maria Victoria R. and Krusche, Alex V. and Salimon, Cleber and Montebelo, Leticia A. and Alin, Simone R. and Victoria, Reynaldo L. and Richey, Jeffrey E.}, title = {Small rivers in the southwestern Amazon and their role in CO(2) outgassing}, journal = {Earth Interactions}, year = {2008}, volume = {12}, url = {://WOS:000257246400001}, doi = {https://doi.org/10.1175/2008ei257.1} } |
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Rap, A., Spracklen, D.V., Mercado, L., Reddington, C.L., Haywood, J.M., Ellis, R.J., Phillips, O.L., Artaxo, P., Bonal, D., Restrepo Coupe, N. and Butt, N. | Fires increase Amazon forest productivity through increases in diffuse radiation [BibTeX] |
2015 | Geophysical Research Letters Vol. 42 |
article | DOI |
BibTeX:
@article{rap_fires_2015, author = {Rap, A. and Spracklen, D. V. and Mercado, L. and Reddington, C. L. and Haywood, J. M. and Ellis, R. J. and Phillips, O. L. and Artaxo, P. and Bonal, D. and Restrepo Coupe, N. and Butt, N.}, title = {Fires increase Amazon forest productivity through increases in diffuse radiation}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, doi = {https://doi.org/10.1002/2015GL063719} } |
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Randow, R. and Alvalá, R. | Estimativa da radiação de onda longa atmosférica no pantanal sul matogrossense durante os períodos secos de 1999 e 2000 [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 398-412 |
article | |
BibTeX:
@article{randow_estimativa_2006, author = {Randow, R.C.S. and Alvalá, R.C.S.}, title = {Estimativa da radiação de onda longa atmosférica no pantanal sul matogrossense durante os períodos secos de 1999 e 2000}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {398--412} } |
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Randow, C.v., Miranda, F. and Sá, L.D.A. | Modulação da camada limite superficial na Amazônia por movimentos de baixa frequência [BibTeX] |
2016 | Ciência & Natura, Vol. 38(Ed. Especial- IX Workshop Brasileiro de Micrometeorologia), pp. 442 - 446 |
article | DOI |
BibTeX:
@article{randow_modulacao_2016, author = {Randow, C. von and Miranda, F. and Sá, L. D. A.}, title = {Modulação da camada limite superficial na Amazônia por movimentos de baixa frequência}, journal = {Ciência & Natura,}, year = {2016}, volume = {38}, number = {Ed. Especial- IX Workshop Brasileiro de Micrometeorologia}, pages = {442 -- 446}, doi = {https://doi.org/10.5902/2179460X20313} } |
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Ramsay, R., Di Marco, C.F., Sörgel, M., Heal, M.R., Carbone, S., Artaxo, P., de Araùjo, A.C., Sá, M., Pöhlker, C., Lavric, J., Andreae, M.O. and Nemitz, E. | Concentrations and biosphere–atmosphere fluxes of inorganic trace gases and associated ionic aerosol counterparts over the Amazon rainforest [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(24), pp. 15551-15584 |
article | DOI URL |
BibTeX:
@article{ramsay_concentrations_2020, author = {Ramsay, R. and Di Marco, C. F. and Sörgel, M. and Heal, M. R. and Carbone, S. and Artaxo, P. and de Araùjo, A. C. and Sá, M. and Pöhlker, C. and Lavric, J. and Andreae, M. O. and Nemitz, E.}, title = {Concentrations and biosphere–atmosphere fluxes of inorganic trace gases and associated ionic aerosol counterparts over the Amazon rainforest}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {24}, pages = {15551--15584}, url = {https://acp.copernicus.org/articles/20/15551/2020/}, doi = {https://doi.org/10.5194/acp-20-15551-2020} } |
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Ramos, F.M., Lima, I.B.T., Rosa, R.R., Mazzi, E.A., Carvalho, J.C., Rasera, M.F.F.L., Ometto, J.P.H.B., Assireu, A.T. and Stech, J.L. | Extreme event dynamics in methane ebullition fluxes from tropical reservoirs | 2006 | Geophysical Research Letters Vol. 33(21) |
article | DOI URL |
Abstract: Tropical hydroelectric reservoirs generally constitute an appreciable source of CH(4) (methane), a potent greenhouse gas. In this letter, we investigate the statistical characteristics of methane ebullition fluxes in hydroelectric reservoirs. To this end, we use CH(4) flux measurements obtained in Manso (wet season, 2004) and Corumba (dry and wet seasons, 2005) reservoirs, located respectively in Mato Grosso and Goias, Brazil. Methane ebullition fluxes were measured using open dynamic chambers, connected to an infrared photo-acoustic trace gas analyzer (TGA). Our main result indicates that when properly rescaled, all methane ebullition data collapse into a single statistic well described by a Generalized Pareto distribution, with shape parameter well above zero. The approach presented here, which combines high-frequency CH(4) ebullition data and Extreme Value theory analytical tools, shows that, although bubbling patterns appear to be highly complex and unpredictable, they may still be described by a rather simple ( but non trivial) dynamics. | |||||
BibTeX:
@article{ramos_extreme_2006, author = {Ramos, Fernando M. and Lima, Ivan B. T. and Rosa, Reinaldo R. and Mazzi, Edmar A. and Carvalho, Joao C. and Rasera, Maria F. F. L. and Ometto, Jean P. H. B. and Assireu, Arcilan T. and Stech, Jose L.}, title = {Extreme event dynamics in methane ebullition fluxes from tropical reservoirs}, journal = {Geophysical Research Letters}, year = {2006}, volume = {33}, number = {21}, url = {://WOS:000241866000007}, doi = {https://doi.org/10.1029/2006gl027943} } |
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Ramos, F.M., Bolzan, M.J.A., Sa, L.D.A. and Rosa, R.R. | Atmospheric turbulence within and above an Amazon forest | 2004 | Physica D-Nonlinear Phenomena Vol. 193(1-4), pp. 278-291 |
article | DOI URL |
Abstract: In this paper, we discuss the impact of a rain forest canopy on the statistical characteristics of atmospheric turbulence. This issue is of particular interest for understanding on how the Amazon terrestrial biosphere interacts with the atmosphere. For this, we used a probability density function model of velocity and temperature differences based on Tsallis' non-extensive thermostatistics. We compared theoretical results with experimental data measured in a 66 m micrometeorological tower, during the wet-season campaign of the large-scale biosphere-atmosphere experiment in Amazonia (LBA). Particularly, we investigated how the value of the entropic parameter is affected when one moves into the canopy, or when one passes from day/unstable to night/stable conditions. We show that this new approach provides interesting insights on turbulence in a complex environment such as the Amazon forest. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{ramos_atmospheric_2004, author = {Ramos, F. M. and Bolzan, M. J. A. and Sa, L. D. A. and Rosa, R. R.}, title = {Atmospheric turbulence within and above an Amazon forest}, journal = {Physica D-Nonlinear Phenomena}, year = {2004}, volume = {193}, number = {1-4}, pages = {278--291}, url = {://WOS:000222154400023}, doi = {https://doi.org/10.1016/j.physd.2004.01.026} } |
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Ramankutty, N., Gibbs, H.K., Achard, F., Defriess, R., Foley, J.A. and Houghton, R.A. | Challenges to estimating carbon emissions from tropical deforestation | 2007 | Global Change Biology Vol. 13(1), pp. 51-66 |
article | DOI URL |
Abstract: An accurate estimate of carbon fluxes associated with tropical deforestation from the last two decades is needed to balance the global carbon budget. Several studies have already estimated carbon emissions from tropical deforestation, but the estimates vary greatly and are difficult to compare due to differences in data sources, assumptions, and methodologies. In this paper, we review the different estimates and datasets, and the various challenges associated with comparing them and with accurately estimating carbon emissions from deforestation. We performed a simulation study over legal Amazonia to illustrate some of these major issues. Our analysis demonstrates the importance of considering land-cover dynamics following deforestation, including the fluxes from reclearing of secondary vegetation, the decay of product and slash pools, and the fluxes from regrowing forest. It also suggests that accurate carbon-flux estimates will need to consider historical land-cover changes for at least the previous 20 years. However, this result is highly sensitive to estimates of the partitioning of cleared carbon into instantaneous burning vs. long-timescale slash pools. We also show that carbon flux estimates based on 'committed flux' calculations, as used by a few studies, are not comparable with the 'annual balance' calculation method used by other studies. | |||||
BibTeX:
@article{ramankutty_challenges_2007, author = {Ramankutty, Navin and Gibbs, Holly K. and Achard, Frederic and Defriess, Ruth and Foley, Jonathan A. and Houghton, R. A.}, title = {Challenges to estimating carbon emissions from tropical deforestation}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {1}, pages = {51--66}, url = {://WOS:000243403900005 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2006.01272.x/asset/j.1365-2486.2006.01272.x.pdf?v=1&t=h6hwt6ni&s=c6d1b666571b683782571ff6789600a4b321e0ed}, doi = {https://doi.org/10.1111/j.1365-2486.2006.01272.x} } |
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Ramankutty, N., Foley, J.A., Norman, J. and McSweeney, K. | The global distribution of cultivable lands: current patterns and sensitivity to possible climate change | 2002 | Global Ecology and Biogeography Vol. 11(5), pp. 377-392 |
article | DOI URL |
Abstract: Aim This study makes quantitative global estimates of land suitability for cultivation based on climate and soil constraints. It evaluates further the sensitivity of croplands to any possible changes in climate and atmospheric CO2 concentrations. Location The location is global, geographically explicit. Methods The methods used are spatial data synthesis and analysis and numerical modelling. Results There is a cropland 'reserve' of 120%, mainly in tropical South America and Africa. Our climate sensitivity analysis indicates that the southern provinces of Canada, north-western and north-central states of the United States, northern Europe, southern Former Soviet Union and the Manchurian plains of China are most sensitive to changes in temperature. The Great Plains region of the United States and north-eastern China are most sensitive to changes in precipitation. The regions that are sensitive to precipitation change are also sensitive to changes in CO2, but the magnitude is small compared to the influence of direct climate change. We estimate that climate change, as simulated by global climate models, will expand cropland suitability by an additional 16%, mainly in the Northern Hemisphere high latitudes. However, the tropics (mainly Africa, northern South America, Mexico and Central America and Oceania) will experience a small decrease in suitability due to climate change. Main conclusions There is a large reserve of cultivable croplands, mainly in tropical South America and Africa. However, much of this land is under valuable forests or in protected areas. Furthermore, the tropical soils could potentially lose fertility very rapidly once the forest cover is removed. Regions that lie at the margins of temperature or precipitation limitation to cultivation are most sensitive to changes in climate and atmospheric CO2 concentration. It is anticipated that climate change will result in an increase in cropland suitability in the Northern Hemisphere high latitudes (mainly in developed nations), while the tropics will lose suitability (mainly in developing nations). | |||||
BibTeX:
@article{ramankutty_global_2002, author = {Ramankutty, N. and Foley, J. A. and Norman, J. and McSweeney, K.}, title = {The global distribution of cultivable lands: current patterns and sensitivity to possible climate change}, journal = {Global Ecology and Biogeography}, year = {2002}, volume = {11}, number = {5}, pages = {377--392}, url = {://WOS:000178189800003}, doi = {https://doi.org/10.1046/j.1466-822x.2002.00294.x} } |
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Quesada, J., Grossmann, D., Fernandez, E., Romero, J., Sanhueza, E., Moortgat, G. and Crutzen, P.J. | Ground based gas phase measurements in Surinam during the LBA-Claire 98 experiment | 2001 | Journal of Atmospheric Chemistry Vol. 39(1), pp. 15-36 |
article | DOI URL |
Abstract: As part of the LBA-CLAIRE-98 experiment, ground level atmospheric concentrations of O-3, CO, hydroperoxides and organic acids were measured in the rainforest region in Surinam. Measurements of CO and O-3 were also made at a coastal site. The results suggest that a significant consumption of 'boundary layer' ozone occurs over the forested region of Surinam, with an estimated net ozone consumption of about 5% hr(-1) during daytime. This would be mainly explained by a low photochemical production and high dry deposition to the forest vegetation. Compared to other tropical sites, lower levels of H2O2 were observed at the rainforest site, with an average boundary layer concentration of 0.55 +/- 0.2 nmol mol(-1). Also acetic and formic acids showed relatively low average boundary layer mixing ratios; 1.1 +/- 0.4 nmol mol(-1) and 1.4 +/- 0.5 nmol mol(-1), respectively. Significant correlations were found between both acids and between the acids and hydrogen peroxide, suggesting an atmospheric source for the acids. From the available observations we discuss possible implications of our measurements for the O-3, HO2, and NOx budgets and concentrations in the boundary layer. We conclude that, despite the high solar irradiation, relatively low levels of O-3, H2O2, HCOOH and CH3COOH are observed in the boundary layer of the rainforest of Surinam, probably due to low levels of NOx and high levels of VOCs, which leads to loss of OH and HO2 radicals. Additionally, high deposition rates of these gases occur to the forest vegetation. | |||||
BibTeX:
@article{quesada_ground_2001, author = {Quesada, J. and Grossmann, D. and Fernandez, E. and Romero, J. and Sanhueza, E. and Moortgat, G. and Crutzen, P. J.}, title = {Ground based gas phase measurements in Surinam during the LBA-Claire 98 experiment}, journal = {Journal of Atmospheric Chemistry}, year = {2001}, volume = {39}, number = {1}, pages = {15--36}, url = {://WOS:000168190200002}, doi = {https://doi.org/10.1023/a:1010762209008} } |
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Quesada, C.A., Phillips, O.L., Schwarz, M., Czimczik, C.I., Baker, T.R., Patiño, S., Fyllas, N.M., Hodnett, M.G., Herrera, R., Almeida, S., Alvarez Dávila, E., Arneth, A., Arroyo, L., Chao, K.J., Dezzeo, N., Erwin, T., di Fiore, A., Higuchi, N., Honorio Coronado, E., Jimenez, E.M., Killeen, T., Lezama, A.T., Lloyd, G., López-González, G., Luizão, F.J., Malhi, Y., Monteagudo, A., Neill, D.A., Núñez Vargas, P., Paiva, R., Peacock, J., Peñuela, M.C., Peña Cruz, A., Pitman, N., Priante Filho, N., Prieto, A., Ramírez, H., Rudas, A., Salomão, R., Santos, A.J.B., Schmerler, J., Silva, N., Silveira, M., Vásquez, R., Vieira, I., Terborgh, J. and Lloyd, J. | Basin-wide variations in Amazon forest structure and function are mediated by both soils and climate [BibTeX] |
2012 | Biogeosciences Vol. 9(6), pp. 2203-2246 |
article | DOI URL |
BibTeX:
@article{quesada_basin-wide_2012, author = {Quesada, C. A. and Phillips, O. L. and Schwarz, M. and Czimczik, C. I. and Baker, T. R. and Patiño, S. and Fyllas, N. M. and Hodnett, M. G. and Herrera, R. and Almeida, S. and Alvarez Dávila, E. and Arneth, A. and Arroyo, L. and Chao, K. J. and Dezzeo, N. and Erwin, T. and di Fiore, A. and Higuchi, N. and Honorio Coronado, E. and Jimenez, E. M. and Killeen, T. and Lezama, A. T. and Lloyd, G. and López-González, G. and Luizão, F. J. and Malhi, Y. and Monteagudo, A. and Neill, D. A. and Núñez Vargas, P. and Paiva, R. and Peacock, J. and Peñuela, M. C. and Peña Cruz, A. and Pitman, N. and Priante Filho, N. and Prieto, A. and Ramírez, H. and Rudas, A. and Salomão, R. and Santos, A. J. B. and Schmerler, J. and Silva, N. and Silveira, M. and Vásquez, R. and Vieira, I. and Terborgh, J. and Lloyd, J.}, title = {Basin-wide variations in Amazon forest structure and function are mediated by both soils and climate}, journal = {Biogeosciences}, year = {2012}, volume = {9}, number = {6}, pages = {2203--2246}, url = {http://www.biogeosciences.net/9/2203/2012/bg-9-2203-2012.pdf}, doi = {https://doi.org/10.5194/bg-9-2203-2012} } |
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Quesada, C.A., Miranda, A.C., Hodnett, M.G., Santos, A.J.B., Miranda, H.S. and Breyer, L.M. | Seasonal and depth variation of soil moisture in a burned open savanna (campo sujo) in central Brazil | 2004 | Ecological Applications Vol. 14(4), pp. S33-S41 |
article | URL |
Abstract: The soil water regimes of two areas of open savanna (campo sujo) near Brasilia, Brazil, were monitored between August 1999 and November 2000. Each area was subjected to a different fire regime. Soil water content was measured to a depth of 3.6 in, using a neutron probe. The profile storage at the end of the 1999 and 2000 dry seasons was very similar despite a difference in dry season duration and large differences in rainfall in the preceding wet seasons, indicating that the vegetation is conservative in its water use. In the last two months of the dry season, the water content of the upper 0.6 in of the soil profile did not decrease further, suggesting that the vegetation had used,all of the available water in this layer. The seasonal variation in soil water storage to a depth of 3.6 in was 403 mm, 65% of which occurred below I in. The wet and dry season evaporation rates were estimated to be 2.4 mm/d and 1.6 mm/d, respectively, but for a month after fire, before regrowth started, the evaporation rate was less than 0.5 mm/d. | |||||
BibTeX:
@article{quesada_seasonal_2004, author = {Quesada, C. A. and Miranda, A. C. and Hodnett, M. G. and Santos, A. J. B. and Miranda, H. S. and Breyer, L. M.}, title = {Seasonal and depth variation of soil moisture in a burned open savanna (campo sujo) in central Brazil}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S33--S41}, url = {://WOS:000223269000005} } |
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Quesada, C.A., Lloyd, J., Schwarz, M., Patino, S., Baker, T.R., Czimczik, C., Fyllas, N.M., Martinelli, L., Nardoto, G.B., Schmerler, J., Santos, A.J.B., Hodnett, M.G., Herrera, R., Luizao, F.J., Arneth, A., Lloyd, G., Dezzeo, N., Hilke, I., Kuhlmann, I., Raessler, M., Brand, W.A., Geilmann, H., Moraes Filho, J.O., Carvalho, F.P., Araujo Filho, R.N., Chaves, J.E., Cruz Junior, O.F., Pimentel, T.P. and Paiva, R. | Variations in chemical and physical properties of Amazon forest soils in relation to their genesis | 2010 | Biogeosciences Vol. 7(5), pp. 1515-1541 |
article | DOI URL |
Abstract: Soil samples were collected in six South American countries in a total of 71 different 1 ha forest plots across the Amazon Basin as part of the RAINFOR project. They were analysed for total and exchangeable cations, C, N, pH with various P fractions also determined. Physical properties were also examined and an index of soil physical quality proposed. A diverse range of soils was found. For the western areas near the Andean cordillera and the southern and northern fringes, soils tend to be distributed among the lower pedogenetic levels, while the central and eastern areas of Amazonia have more intensely weathered soils. This gives rise to a large variation of soil chemical and physical properties across the Basin, with soil properties varying predictably along a gradient of pedogenic development. Nutrient pools generally increased slightly in concentration from the youngest to the intermediate aged soils after which a gradual decline was observed with the lowest values found in the most weathered soils. Soil physical properties were strongly correlated with soil fertility, with favourable physical properties occurring in highly weathered and nutrient depleted soils and with the least weathered, more fertile soils having higher incidence of limiting physical properties. Soil phosphorus concentrations varied markedly in accordance with weathering extent and appear to exert an important influence on the nitrogen cycle of Amazon forest soils. | |||||
BibTeX:
@article{quesada_variations_2010, author = {Quesada, C. A. and Lloyd, J. and Schwarz, M. and Patino, S. and Baker, T. R. and Czimczik, C. and Fyllas, N. M. and Martinelli, L. and Nardoto, G. B. and Schmerler, J. and Santos, A. J. B. and Hodnett, M. G. and Herrera, R. and Luizao, F. J. and Arneth, A. and Lloyd, G. and Dezzeo, N. and Hilke, I. and Kuhlmann, I. and Raessler, M. and Brand, W. A. and Geilmann, H. and Moraes Filho, J. O. and Carvalho, F. P. and Araujo Filho, R. N. and Chaves, J. E. and Cruz Junior, O. F. and Pimentel, T. P. and Paiva, R.}, title = {Variations in chemical and physical properties of Amazon forest soils in relation to their genesis}, journal = {Biogeosciences}, year = {2010}, volume = {7}, number = {5}, pages = {1515--1541}, url = {://WOS:000278184500011}, doi = {https://doi.org/10.5194/bg-7-1515-2010} } |
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Quesada, C.A., Lloyd, J., Anderson, L.O., Fyllas, N.M., Schwarz, M. and Czimczik, C.I. | Soils of Amazonia with particular reference to the RAINFOR sites | 2011 | Biogeosciences Vol. 8(6), pp. 1415-1440 |
article | DOI URL |
Abstract: The tropical forests of the Amazon Basin occur on a wide variety of different soil types reflecting a rich diversity of geologic origins and geomorphic processes. We here review the existing literature about the main soil groups of Amazonia, describing their genesis, geographical patterns and principal chemical, physical and morphologic characteristics. Original data is also presented, with profiles of exchangeable cations, carbon and particle size fraction illustrated for the principal soil types; also emphasizing the high diversity existing within the main soil groups when possible. Maps of geographic distribution of soils occurring under forest vegetation are also introduced, and to contextualize soils into an evolutionary framework, a scheme of soil development is presented having as its basis a chemical weathering index. We identify a continuum of soil evolution in Amazonia with soil properties varying predictably along this pedogenetic gradient. | |||||
BibTeX:
@article{quesada_soils_2011, author = {Quesada, C. A. and Lloyd, J. and Anderson, L. O. and Fyllas, N. M. and Schwarz, M. and Czimczik, C. I.}, title = {Soils of Amazonia with particular reference to the RAINFOR sites}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {6}, pages = {1415--1440}, url = {://WOS:000291942900001}, doi = {https://doi.org/10.5194/bg-8-1415-2011} } |
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Querino, C.A.S., Smeets, C.J.P.P., Vigano, I., Holzinger, R., Moura, V., Gatti, L.V., Martinewski, A., Manzi, A.O., de Araujo, A.C. and Rockmann, T. | Methane flux, vertical gradient and mixing ratio measurements in a tropical forest | 2011 | Atmospheric Chemistry and Physics Vol. 11(15), pp. 7943-7953 |
article | DOI URL |
Abstract: Measurements of CH(4) mixing ratio, vertical gradients and turbulent fluxes were carried out in a tropical forest (Reserva Biologica Cuieiras), about 60 km north of Manaus, Brazil. The methane mixing ratio and flux measurements were performed at a height of 53 m (canopy height 35 m). In addition, vertical CH(4) gradients were measured within the canopy using custom made air samplers at levels of 2, 16 and 36 m above ground. The methane gradients within the canopy reveal that there is a continuous methane source at the surface. No clear evidence for aerobic methane emission from the canopy was found. The methane fluxes above the canopy are small but consistently upwards with a maximum early in the morning. The measured fluxes are in agreement with the observed CH(4) gradient in the canopy. In the morning hours, a strong canopy venting peak is observed for both CH(4) and CO(2), but for CO(2) this peak is then superimposed by photosynthetic uptake, whereas the peak lasts longer for CH(4). Monthly averaged diurnal cycles of the CH(4) mixing ratio show a decrease during daytime and increase during nighttime. The magnitude of the difference in CH(4) mixing ratio between day and night gradually increases throughout the wet season. The fluxes required to explain the nighttime increase are in agreement with the nighttime fluxes measured above the canopy, which implies that the CH(4) increase in the nighttime boundary layer originates from local sources. | |||||
BibTeX:
@article{querino_methane_2011, author = {Querino, C. A. S. and Smeets, C. J. P. P. and Vigano, I. and Holzinger, R. and Moura, V. and Gatti, L. V. and Martinewski, A. and Manzi, A. O. and de Araujo, A. C. and Rockmann, T.}, title = {Methane flux, vertical gradient and mixing ratio measurements in a tropical forest}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, number = {15}, pages = {7943--7953}, url = {://WOS:000293826500032}, doi = {https://doi.org/10.5194/acp-11-7943-2011} } |
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Querino, C.A.S., Biudes, M.S., Machado, N.G., Querino, J.K.A.S., Santos Neto, L.A., Silva, M.J.G., Arruda, P. and Nogueira, J.S. | Balanço de ondas curtas sobre floresta sazonalmente alagável do pantanal mato-grossense [BibTeX] |
2017 | Revista Brasileira de Climatologia Vol. 20, pp. 252-266 |
article | |
BibTeX:
@article{querino_balanco_2017, author = {Querino, C. A. S. and Biudes, M. S. and Machado, N. G. and Querino, J. K. A. S. and Santos Neto, L. A. and Silva, M. J. G. and Arruda, P.H.Z. and Nogueira, J. S.}, title = {Balanço de ondas curtas sobre floresta sazonalmente alagável do pantanal mato-grossense}, journal = {Revista Brasileira de Climatologia}, year = {2017}, volume = {20}, pages = {252--266} } |
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Querino, M., M.A.L., L., R.F. F., M. and C.A.S., G.L. | Avaliação e comparação de radiação solar global e albedo com ângulo zenital na região amazônica [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 3a(21), pp. 42-49 |
article | |
BibTeX:
@article{querino_avaliacao_2006, author = {Querino, Moura, M.A.L., Lyra, R.F. F., Mariano, G.L., C.A.S.}, title = {Avaliação e comparação de radiação solar global e albedo com ângulo zenital na região amazônica}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {3a}, number = {21}, pages = {42--49} } |
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Pyle, E.H., Santoni, G.W., Nascimento, H.E.M., Hutyra, L.R., Vieira, S., Curran, D.J., van Haren, J., Saleska, S.R., Chow, V.Y., Carmago, P.B., Laurance, W.F. and Wofsy, S.C. | Dynamics of carbon, biomass, and structure in two Amazonian forests | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: Amazon forests are potentially globally significant sources or sinks for atmospheric carbon dioxide. In this study, we characterize the spatial trends in carbon storage and fluxes in both live and dead biomass (necromass) in two Amazonian forests, the Biological Dynamic of Forest Fragments Project (BDFFP), near Manaus, Amazonas, and the Tapajos National Forest (TNF) near Santarem, Para. We assessed coarse woody debris (CWD) stocks, tree growth, mortality, and recruitment in ground-based plots distributed across the terra firme forest at both sites. Carbon dynamics were similar within each site, but differed significantly between the sites. The BDFFP and the TNF held comparable live biomass (167 +/- 7.6 MgC.ha(-1) versus 149 +/- 6.0 MgC.ha(-1), respectively), but stocks of CWD were 2.5 times larger at TNF (16.2 +/- 1.5 MgC.ha(-1) at BDFFP, versus 40.1 +/- 3.9 MgC.ha(-1) at TNF). A model of current forest dynamics suggests that the BDFFP was close to carbon balance, and its size class structure approximated a steady state. The TNF, by contrast, showed rapid carbon accrual to live biomass (3.24 +/- 0.22 MgC.ha(-1).a(-1) in TNF, 2.59 +/- 0.16 MgC.ha(-1).a(-1) in BDFFP), which was more than offset by losses from large stocks of CWD, as well as ongoing shifts of biomass among size classes. This pattern in the TNF suggests recovery from a significant disturbance. The net loss of carbon from the TNF will likely last 10 - 15 years after the initial disturbance (controlled by the rate of decay of coarse woody debris), followed by uptake of carbon as the forest size class structure and composition continue to shift. The frequency and longevity of forests showing such disequilibruim dynamics within the larger matrix of the Amazon remains an essential question to understanding Amazonian carbon balance. | |||||
BibTeX:
@article{pyle_dynamics_2008, author = {Pyle, Elizabeth Hammond and Santoni, Gregory W. and Nascimento, Henrique E. M. and Hutyra, Lucy R. and Vieira, Simone and Curran, Daniel J. and van Haren, Joost and Saleska, Scott R. and Chow, V. Y. and Carmago, Plinio B. and Laurance, William F. and Wofsy, Steven C.}, title = {Dynamics of carbon, biomass, and structure in two Amazonian forests}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000260994700001}, doi = {https://doi.org/10.1029/2007jg000592} } |
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Procopio, A.S., Remer, L.A., Artaxo, P., Kaufman, Y.J. and Holben, B.N. | Modeled spectral optical properties for smoke aerosols in Amazonia | 2003 | Geophysical Research Letters Vol. 30(24) |
article | DOI URL |
Abstract: The optical properties of aerosols from biomass burning in Brazil were derived from measurements by the AERONET sun photometer network in Amazonia. A dynamical aerosol model was constructed from Mie Theory calculations, using as input a constant complex refractive index and the average size distribution of aerosols for 12 ranges of aerosol optical thickness. The aerosol optical properties were described for 24 wavelengths in the spectral range of 0.20-3.00 mum. The model was used to simulate radiances and irradiances and the results agreed well with the measurements. The derived optical model is immediately applicable to estimate aerosol forcing by biomass burning aerosol emitted on the development frontier in Amazonia. | |||||
BibTeX:
@article{procopio_modeled_2003, author = {Procopio, A. S. and Remer, L. A. and Artaxo, P. and Kaufman, Y. J. and Holben, B. N.}, title = {Modeled spectral optical properties for smoke aerosols in Amazonia}, journal = {Geophysical Research Letters}, year = {2003}, volume = {30}, number = {24}, url = {://WOS:000187864700001}, doi = {https://doi.org/10.1029/2003gl018063} } |
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Procopio, A.S., Artaxo, P., Kaufman, Y.J., Remer, L.A., Schafer, J.S. and Holben, B.N. | Multiyear analysis of amazonian biomass burning smoke radiative forcing of climate | 2004 | Geophysical Research Letters Vol. 31(3) |
article | DOI URL |
Abstract: Seven years analysis of clear-sky aerosol direct radiative forcing is presented for two locations in the Amazon Region heavily impacted by biomass burning emissions. During the dry season, the monthly average direct forcing at the top of the atmosphere, deduced from measurements, varied from -5 to -12 W/m(2) and at the surface from -21 to -74 W/m(2), with the difference associated with absorption of sunlight by the smoke aerosol layer. The spatial distribution of the forcings over Amazonia showed that they affect an area over 1.2-2.6 million square kilometers. | |||||
BibTeX:
@article{procopio_multiyear_2004, author = {Procopio, A. S. and Artaxo, P. and Kaufman, Y. J. and Remer, L. A. and Schafer, J. S. and Holben, B. N.}, title = {Multiyear analysis of amazonian biomass burning smoke radiative forcing of climate}, journal = {Geophysical Research Letters}, year = {2004}, volume = {31}, number = {3}, url = {://WOS:000189050600001}, doi = {https://doi.org/10.1029/2003gl018646} } |
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Pritchard, J.f., Ferraz, J.B., Marks, T.R., Camargo, J.L.C., Nadarajan, J., Ferraz Isolde D.K. ., H. and Moat | Innovative approaches to the preservation of forest trees [BibTeX] |
2014 | Forest Ecology and Management Vol. 1, pp. 1-11 |
article | |
BibTeX:
@article{pritchard_innovative_2014, author = {Pritchard, Justin f. ; Ferraz, João B.S. ; Marks, Timothy R. ; Camargo, José Luís C. ; Nadarajan, Jayanthi ; Ferraz, Isolde D.K. ., H.W.; Moat}, title = {Innovative approaches to the preservation of forest trees}, journal = {Forest Ecology and Management}, year = {2014}, volume = {1}, pages = {1--11} } |
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Prince, S.D. and Steininger, M.K. | Biophysical stratification of the Amazon basin | 1999 | Global Change Biology Vol. 5(1), pp. 1-22 |
article | DOI URL |
Abstract: In field measurement programmes, stratified sampling can optimize sampling efficiency, but stratification is often undertaken subjectively, and is frequently based on a priori classification schemes such as those used for vegetation maps. In order to avoid the problems associated with a priori subjective schemes, we explore here an objective procedure, Regression Tree Analysis (RTA). RTA has previously been used in local-scale studies, but here we apply it to a very large study domain, namely the entire humid tropical zone of South America. The aim of the study was to develop an optimal sampling design in preparation for the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). Go-registered spatially continuous fields of rainfall, temperature, photosynthetically active radiation (PAR), the normalized difference index (NDVI), an index of surface moisture, and other independent variables were used to predict three dependent variables, annual net radiation (Rn), latent heat (LE) and net primary production (NPP). Rather than simply dividing the study area based on differing levels of the three dependent variables, empirical models were developed using RTA to indicate how the relationships between these and possible forcing variables vary across the study area. For each variable long-term seasonal indices such as annual average, monthly minimum and amplitude were used to exclude effects of temporal phase differences between the hemispheres. The resulting hierarchical models revealed variations in the interdependence of the forcing variables throughout the study area and therefore provided a basis for a stratified sampling and identifying the most important variables to be collected in LBA for the Amazon basin as a whole as well as optimizing the sampling scheme for scaling up findings from the field scale to larger areas. | |||||
BibTeX:
@article{prince_biophysical_1999, author = {Prince, S. D. and Steininger, M. K.}, title = {Biophysical stratification of the Amazon basin}, journal = {Global Change Biology}, year = {1999}, volume = {5}, number = {1}, pages = {1--22}, url = {://WOS:000078411000002 http://onlinelibrary.wiley.com/store/10.1046/j.1365-2486.1998.00220.x/asset/j.1365-2486.1998.00220.x.pdf?v=1&t=h6hwp4k5&s=61f7e87cfb023b7c3aaede465a515da5b7405e90}, doi = {https://doi.org/10.1046/j.1365-2486.1998.00220.x} } |
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Priante, N., Vourlitis, G.L., Hayashi, M.M.S., Nogueira, J.D., Campelo, J.H., Nunes, P.C., Souza, L.S.E., Couto, E.G., Hoeger, W., Raiter, F., Trienweiler, J.L., Miranda, E.J., Priante, P.C., Fritzen, C.L., Lacerda, M., Pereira, L.C., Biudes, M.S., Suli, G.S., Shiraiwa, S., Do Paulo, S.R. and Silveira, M. | Comparison of the mass and energy exchange of a pasture and a mature transitional tropical forest of the southern Amazon Basin during a seasonal transition | 2004 | Global Change Biology Vol. 10(5), pp. 863-876 |
article | DOI URL |
Abstract: This research utilized tower-based eddy covariance to quantify the trends in net ecosystem mass (CO2 and H2O vapor) and energy exchange of important land-cover types of NW Mato Grosso during the March-December 2002 seasonal transition. Measurements were made in a mature transitional (ecotonal) tropical forest near Sinop, Mato Grosso, and a cattle pasture near Cotriguacu, Mato Grosso, located 500 km WNW of Sinop. Pasture net ecosystem CO2 exchange (NEE) was considerably more variable than the forest NEE over the seasonal transition, and the pasture had significantly higher rates of maximum gross primary production in every season except the dry-wet season transition (September-October). The pasture also had significantly higher rates of whole-ecosystem dark respiration than the forest during the wetter times of the year. Average (+/-95% CI) rates of total daily NEE during the March-December 2002 measurement period were 26+/-15 mmol m(-2) day(-1) for the forest (positive values indicate net CO2 loss by the ecosystem) and -38+/-26 mmol m(-2) day(-1) for the pasture. While both ecosystems partitioned more net radiation (R-n) into latent heat flux (L-e), the forest had significantly higher rates of L-e and lower rates of sensible heat flux (H) than the pasture; a trend that became more extreme during the onset of the dry season. Large differences in pasture and forest mass and energy exchange occurred even though seasonal variations in micrometeorology (air temperature, humidity, and radiation) were relatively similar for both ecosystems. While the short measurement period and lack of spatial replication limit the ability to generalize these results to pasture and forest regions of the Amazon Basin, these results suggest important differences in the magnitude and seasonal variation of NEE and energy partitioning for pasture and transitional tropical forest. | |||||
BibTeX:
@article{priante_comparison_2004, author = {Priante, N. and Vourlitis, G. L. and Hayashi, M. M. S. and Nogueira, J. D. and Campelo, J. H. and Nunes, P. C. and Souza, L. S. E. and Couto, E. G. and Hoeger, W. and Raiter, F. and Trienweiler, J. L. and Miranda, E. J. and Priante, P. C. and Fritzen, C. L. and Lacerda, M. and Pereira, L. C. and Biudes, M. S. and Suli, G. S. and Shiraiwa, S. and Do Paulo, S. R. and Silveira, M.}, title = {Comparison of the mass and energy exchange of a pasture and a mature transitional tropical forest of the southern Amazon Basin during a seasonal transition}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {863--876}, url = {://WOS:000221421600023}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00775.x} } |
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Prentice, I.C. and Lloyd, J. | C-quest in the Amazon Basin [BibTeX] |
1998 | Nature Vol. 396(6712), pp. 619-620 |
article | DOI URL |
BibTeX:
@article{prentice_c-quest_1998, author = {Prentice, I. C. and Lloyd, J.}, title = {C-quest in the Amazon Basin}, journal = {Nature}, year = {1998}, volume = {396}, number = {6712}, pages = {619--620}, url = {://WOS:000077694200022}, doi = {https://doi.org/10.1038/25224} } |
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Prenni, A.J., Petters, M.D., Kreidenweis, S.M., Heald, C.L., Martin, S.T., Artaxo, P., Garland, R.M., Wollny, A.G. and Poeschl, U. | Relative roles of biogenic emissions and Saharan dust as ice nuclei in the Amazon basin | 2009 | Nature Geoscience Vol. 2(6), pp. 401-404 |
article | DOI URL |
Abstract: Some aerosol particles, known as ice nuclei, can initiate ice formation in clouds, thereby influencing precipitation, cloud dynamics and the amount of incoming and outgoing solar radiation. In the absence of biomass burning, aerosol mass concentrations in the Amazon basin are low(1). Tropical forests emit primary biological particles directly into the atmosphere; secondary organic aerosols form from the emission and oxidation of biogenic gases(2). In addition, particles derived from biomass burning in central Africa, marine aerosols, and windblown dust from North Africa(3-5) often reach the central part of the Amazon basin during the wet season. The contribution of these aerosol sources to ice nucleation in the region is uncertain. Here we present observations of the concentration and elemental composition of ice nuclei in the Amazon basin during the wet season. Using transmission electron microscopy combined with energy-dispersive X-ray spectroscopy, we show that ice nuclei are primarily composed of carbonaceous material and dust. We show that biological particles dominate the carbonaceous fraction, whereas import of Saharan dust explains the intermittent appearance of dust-containing nuclei. We conclude that ice-nucleus concentration and abundance can be explained almost entirely by local emissions of biological particles supplemented by import of Saharan dust. Using a simple model, we tentatively suggest that the contribution of local biological particles to ice nucleation is increased at higher atmospheric temperatures, whereas the contribution of dust particles is increased at lower temperatures. | |||||
BibTeX:
@article{prenni_relative_2009, author = {Prenni, Anthony J. and Petters, Markus D. and Kreidenweis, Sonia M. and Heald, Colette L. and Martin, Scot T. and Artaxo, Paulo and Garland, Rebecca M. and Wollny, Adam G. and Poeschl, Ulrich}, title = {Relative roles of biogenic emissions and Saharan dust as ice nuclei in the Amazon basin}, journal = {Nature Geoscience}, year = {2009}, volume = {2}, number = {6}, pages = {401--404}, url = {://WOS:000266543200015}, doi = {https://doi.org/10.1038/ngeo517} } |
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Prass, M., Andreae, M.O., de Araùjo, A.C., Artaxo, P., Ditas, F., Elbert, W., Förster, J.D., Franco, M.A., Hrabe de Angelis, I., Kesselmeier, J., Klimach, T., Kremper, L.A., Thines, E., Walter, D., Weber, J., Weber, B., Fuchs, B.M., Pöschl, U. and Pöhlker, C. | Bioaerosols in the Amazon rain forest: temporal variations and vertical profiles of Eukarya, Bacteria, and Archaea [BibTeX] |
2021 | Biogeosciences Vol. 18(17), pp. 4873-4887 |
article | DOI URL |
BibTeX:
@article{prass_bioaerosols_2021, author = {Prass, M. and Andreae, M. O. and de Araùjo, A. C. and Artaxo, P. and Ditas, F. and Elbert, W. and Förster, J. D. and Franco, M. A. and Hrabe de Angelis, I. and Kesselmeier, J. and Klimach, T. and Kremper, L. A. and Thines, E. and Walter, D. and Weber, J. and Weber, B. and Fuchs, B. M. and Pöschl, U. and Pöhlker, C.}, title = {Bioaerosols in the Amazon rain forest: temporal variations and vertical profiles of Eukarya, Bacteria, and Archaea}, journal = {Biogeosciences}, year = {2021}, volume = {18}, number = {17}, pages = {4873--4887}, url = {https://bg.copernicus.org/articles/18/4873/2021/}, doi = {https://doi.org/10.5194/bg-18-4873-2021} } |
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Powell, T.L., Wheeler, J.K., Oliveira, A.A.R.d., Costa, A.C.L.d., Saleska, S.R., Meir, P. and Moorcroft, P.R. | Differences in xylem and leaf hydraulic traits explain differences in drought tolerance among mature Amazon rainforest trees [BibTeX] |
2017 | Global Change Biology Vol. 1 |
article | DOI |
BibTeX:
@article{powell_differences_2017, author = {Powell, Thomas L. and Wheeler, James K. and Oliveira, Alex A. R. de and Costa, Antonio Carlos Lola da and Saleska, Scott R. and Meir, Patrick and Moorcroft, Paul R.}, title = {Differences in xylem and leaf hydraulic traits explain differences in drought tolerance among mature Amazon rainforest trees}, journal = {Global Change Biology}, year = {2017}, volume = {1}, doi = {https://doi.org/10.1111/gcb.13731} } |
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Powell, T., Galbraith, D., Christoffersen, B., Harper, A., Imbuzeiro, H., Rowland, L., Almeida, S., Brando, P., Da Costa, A., Costa, M. and al. , e. | Confronting model predictions of carbon fluxes with measurements of Amazon forests subjected to experimental drought [BibTeX] |
2013 | New Phytologist Vol. 200, pp. 350-365 |
article | |
BibTeX:
@article{powell_confronting_2013, author = {Powell, T.L. and Galbraith, D.R. and Christoffersen, B.O. and Harper, A. and Imbuzeiro, H.M.A. and Rowland, L. and Almeida, S. and Brando, P.M. and Da Costa, A.C.L. and Costa, M.H. and al., et}, title = {Confronting model predictions of carbon fluxes with measurements of Amazon forests subjected to experimental drought}, journal = {New Phytologist}, year = {2013}, volume = {200}, pages = {350--365} } |
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Powell, R.L., Roberts, D.A., Dennison, P.E. and Hess, L.L. | Sub-pixel mapping of urban land cover using multiple endmember spectral mixture analysis: Manaus, Brazil | 2007 | Remote Sensing of Environment Vol. 106(2), pp. 253-267 |
article | DOI URL |
Abstract: The spatial and spectral variability Of urban environments present fundamental challenges to deriving accurate remote sensing products for urban areas. Multiple endmember spectral mixture analysis (MESMA) is a technique that potentially addresses both challenges. MESMA models spectra as the linear sum of spectrally pure endmembers that vary on a per-pixel basis. Spatial variability is addressed by mapping sub-pixel components of land cover as a combination of endmembers. Spectral variability is addressed by allowing the number and type of endmembers to vary from pixel to pixel. This paper presents an application of MESMA to map the physical components of urban land cover for the city of Manaus, Brazil, using Landsat Enhanced Thematic Mapper (ETM+) imagery. We present a methodology to build a regionally specific spectral library of urban materials based on generalized categories of urban land-cover components: vegetation, impervious surfaces, soil, and water. Using this library, we applied MESMA to generate a total of H 37 two-, three-, and four-endmember models for each pixel; the model with the lowest root-mean-squared (RMS) error and lowest complexity was selected on a per-pixel basis. Almost 97% of the pixels within the image were modeled within the 2.5% RMS error constraint. The modeled fractions were used to generate Continuous maps of the per-pixel abundance of each generalized land-cover component. We provide an example to demonstrate that land-cover components have the potential to characterize trajectories of physical landscape change as urban neighborhoods develop through time. Accuracy of land-cover fractions was assessed using high-resolution, geocoded images mosaicked from digital aerial videography. Modeled vegetation and impervious fractions corresponded well with the reference fractions. Modeled soil fractions did not correspond as closely with the reference fractions, in part due to limitations of the reference data. This work demonstrates the potential of moderate-resolution, multispectral imagery to map and monitor the evolution of the physical urban environment. (c) 2006 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{powell_sub-pixel_2007, author = {Powell, Rebecca L. and Roberts, Dar A. and Dennison, Philip E. and Hess, Laura L.}, title = {Sub-pixel mapping of urban land cover using multiple endmember spectral mixture analysis: Manaus, Brazil}, journal = {Remote Sensing of Environment}, year = {2007}, volume = {106}, number = {2}, pages = {253--267}, url = {://WOS:000243701500010}, doi = {https://doi.org/10.1016/j.rse.2006.09.005} } |
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Powell, R.L. and Roberts, D.A. | Characterizing Variability of the Urban Physical Environment for a Suite of Cities in Rondonia, Brazil | 2008 | Earth Interactions Vol. 12 |
article | DOI URL |
Abstract: Urban environments are characterized by high spectral and spatial heterogeneity and, as a consequence, most urban pixels in moderate-resolution imagery contain multiple land cover materials. Despite these complexities, virtually all urban land cover can be generalized as a combination of vegetation, impervious surfaces, and soil (V-I-S components), in addition to water. Previous work has demonstrated the potential of multiple endmember spectral mixture analysis (MESMA) to model the subpixel abundance of V-I-S components. Here, the authors test whether the technique is sufficiently robust to map V-I-S components for a diverse set of cities, selecting 10 urban centers in the state of Rondonia, Brazil, to represent a range of populations, development histories, and economic activities. For each urban sample, a 20 km x 20 km region centered over the built-up area was subset from Landsat Enhanced Thematic Mapper Plus (ETM+) imagery. MESMA was applied to all subscenes using the same spectral library, model constraints, and selection rules. Accuracy of the modeled V-I-S fractions was assessed using high-resolution images mosaicked from digital aerial videography. Modeled fractions and reference fractions were highly correlated, with R(2) values exceeding 0.75 for all materials in multiple cities across a region. Model complexity, or the number of endmembers required to accurately model each pixel, was correlated with the degree of human impact on the landscape. Built-up areas, as delineated by model complexity, exhibited a strong fit to the well-established relationship between the built-up area of a settlement and its population. Finally, this work demonstrates that the V-I-S components as modeled by MESMA can capture both inter- and intraurban variability, suggesting that these data products could contribute to comparative studies of urbanizing areas through time and across regions. | |||||
BibTeX:
@article{powell_characterizing_2008, author = {Powell, Rebecca L. and Roberts, Dar A.}, title = {Characterizing Variability of the Urban Physical Environment for a Suite of Cities in Rondonia, Brazil}, journal = {Earth Interactions}, year = {2008}, volume = {12}, url = {://WOS:000260107400001 http://journals.ametsoc.org/doi/pdf/10.1175/2008EI246.1}, doi = {https://doi.org/10.1175/2008ei246.1} } |
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Powell, R.L., Matzke, N., de Souza, C., Clark, M., Numata, I., Hess, L.L. and Roberts, D.A. | Sources of error in accuracy assessment of thematic land-cover maps in the Brazilian Amazon | 2004 | Remote Sensing of Environment Vol. 90(2), pp. 221-234 |
article | DOI URL |
Abstract: Valid measures of map accuracy are critical, yet can be inaccurate even when following well-established procedures. Accuracy assessment is particularly problematic when thematic classes lie along a land-cover continuum, and boundaries between classes are ambiguous. In this study, we examined error sources introduced during accuracy assessment of a regional land-cover map generated from Landsat Thematic Mapper (TM) data in Rond (o) over cap nia, southwestern Brazil. In this dynamic, highly fragmented landscape, the dominant land-cover classes represent a continuum from pasture to second growth to primary forest. We used high spatial resolution, geocoded videography as a reference, and focused on second-growth forest because of its potential contribution to the regional carbon balance. To quantify subjectivity in reference data labeling, we compared reference data produced by five trained interpreters. We also quantified the impact of other error sources, including geolocation errors between the map and reference data, land-cover changes between dates of data collection, heterogeneous reference samples, and edge pixels. Interpreters disagreed on classification of almost 30% of the samples; mixed reference samples and samples located in transitional classes accounted for a majority of disagreements. Agreement on second-growth forest labels between any two interpreters averaged below 50%, while agreement on primary forest was over 90%. Greater than 30% of disagreement between map and reference data was attributed to geolocation error, and 2.4% of disagreement was attributed to change in land cover between dates. After geocorrection, 24% of remaining disagreements corresponded to reference samples with mixed land cover, and 47% corresponded to edge pixels on the classified map. These findings suggest that: (1) labels of continuous land-cover types are more subjective and variable than commonly assumed, especially for transitional classes; however, using multiple interpreters to produce the reference data classification increases reference data accuracy; and (2) validation data sets that include only non-mixed, non-edge samples are likely to result in overly optimistic accuracy estimates, not representative of the map as a whole. These results suggest that different regional estimates of second-growth extent may be inaccurate and difficult to compare. (C) 2004 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{powell_sources_2004, author = {Powell, R. L. and Matzke, N. and de Souza, C. and Clark, M. and Numata, I. and Hess, L. L. and Roberts, D. A.}, title = {Sources of error in accuracy assessment of thematic land-cover maps in the Brazilian Amazon}, journal = {Remote Sensing of Environment}, year = {2004}, volume = {90}, number = {2}, pages = {221--234}, url = {://WOS:000220393800007}, doi = {https://doi.org/10.1016/j.rse.2003.12.007} } |
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Poveda, G. and Zuluaga, M.D. | Testing Taylor's hypothesis in Amazonian rainfall fields during the WETAMC/LBA experiment | 2005 | Advances in Water Resources Vol. 28(11), pp. 1230-1239 |
article | DOI URL |
Abstract: Taylor's hypothesis (TH) for rainfall fields states that the spatial correlation of rainfall intensity at two points at the same instant of time can be equated with the temporal correlation at two instants of time at some fixed location. The validity of TH is tested in a set of 12 storms developed in Rondonia, southwestern Amazonia, Brazil, during the January-February 1999 Wet Season Atmospheric Meso-scale Campaign. The time Eulerian and Lagrangian Autocorrelation Functions (ACF) are estimated, as well as the time-averaged space ACF, using radar rainfall rates of storms spanning between 3.2 and 23 h, measured at 7-10-min time resolution, over a circle of 100 km radius, at 2 km spatial resolution. TH does not hold in 9 out of the 12 studied storms, due to their erratic trajectories and very low values of zonal wind velocity at 700 hPa, independently from underlying atmospheric stability conditions. TH was shown to hold for 3 storms, up to a cutoff time scale of 10-15 min, which is closely related to observed features of the life cycle of convective cells in the region. Such cutoff time scale in Amazonian storms is much shorter than the 40 min identified in mid-latitude convective storms, due to much higher values of CAPE and smaller values of storm speed in Amazonian storms as compared to mid-latitude ones, which in turn contribute to a faster destruction of the rainfall field isotropy. Storms satisfying TH undergo smooth linear trajectories over space, and exhibit the highest negative values of maximum, mean and minimum zonal wind velocity at 700 hPa, within narrow ranges of atmospheric stability conditions. Non-dimensional parameters involving CAPE (maximum, mean and minimum) and CINE (mean) are identified during the storms life cycle, for which TH holds: CAPE mean/CINE mean = [30-35], CAPE max/CINE mean = [32-40], and CAPE min/CINE mean = [22-28]. These findings are independent upon the timing of storms within the diurnal cycle. Also, the estimated Eulerian time ACF's decay faster than the time-averaged space and the Lagrangian time ACF's, irrespectively of TH validity. The Eulerian ACF's exhibit shorter e-folding times, reflecting smaller correlations over short time scales, but also shorter scale of fluctuation, reflecting less persistence in time than over space. No significant associations (linear, exponential or power law) were found between estimated e-folding times and scale of fluctuation, with all estimates of CAPE and CINE. Secondary correlation maxima appear between 50 and 70 min in the Lagrangian time ACF's for storms satisfying TH. No differences were found in the behavior of each of the three ACF's for storms developed during either the Easterly or Westerly zonal wind regimes which characterize the development of meso-scale convective systems over the region. These results have important implications for modelling and downscaling rainfall fields over tropical land areas. (c) 2005 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{poveda_testing_2005, author = {Poveda, G. and Zuluaga, M. D.}, title = {Testing Taylor's hypothesis in Amazonian rainfall fields during the WETAMC/LBA experiment}, journal = {Advances in Water Resources}, year = {2005}, volume = {28}, number = {11}, pages = {1230--1239}, url = {://WOS:000232768000006}, doi = {https://doi.org/10.1016/j.advwatres.2005.03.012} } |
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Poveda, G. and Salazar, L.F. | Annual and interannual (ENSO) variability of spatial scaling properties of a vegetation index (NDVI) in Amazonia | 2004 | Remote Sensing of Environment Vol. 93(3), pp. 391-401 |
article | DOI URL |
Abstract: The space-time variability of the Normalized Difference Vegetation Index (NDVI) over the Amazon River basin is quantified through the bi-dimensional Fourier spectrum, and moment-scaling analysis of monthly imagery at 8 km resolution, for the period July 1981-November 2002. Monthly NDVI fields exhibit power law Fourier spectra, E(k)=ck(-beta), with k denoting the wavenumber, c the prefactor, and the scaling exponent. Fourier spectra exhibit two scaling regimes separated at approximately 29 km, above which NDVI exhibit long-range spatial correlations (0textlessbetatextless2),. and below which NDVI behaves like white noise in space (betasimilar or equal to0). Series of monthly values of c(t) and beta(t) exhibit high negative correlation (-0.88, Ptextgreater0.99), which suggest their linkages in power laws, but also that E-t(k)=c(t)k(-beta(t)), with t the time index. Results show a significant negative simultaneous correlation (-0.82, Ptextgreater0.95) between monthly series of average precipitation over the Amazon, (P(t)), and scaling exponents, beta(t); and high positive lagged correlation (0.63, Ptextgreater0.95), between (P(t)) and (NDVI(t+3)). Parameters also reflect the hydrological seasonal cycle over Amazonia: during the wet season (November-March), beta(t) ranges between 0.9 and 1.15, while during the dry season (May-September), beta(t)similar or equal to1.30. These results reflect the more (less) coherent spatial effect of the dry (wet) season over Amazonia, which translates into longer (shorter)-range spatial correlations of the NDVI field, as witnessed by higher (lower) values of beta(t). At interannual timescales, both phases of ENSO reflect on both parameters, as beta(t) is higher during El Nino than during La Nina, due to the more coherent effects of El Nino-related dryness, whereas NDVI spatial variability is enhanced during La Nina, due to positive rainfall anomalies. Results from the moment-scale analysis indicate the existence of multi-scaling in the spatial variability of NDVI fields. Departures front single scaling exhibit also annual and interannual variability, which consistently reflect the effects from both phases of ENSO. Furthermore, departures from single scaling are independent of the order moment, q, as the PDF of departures scaled by the mean collapse to a unique distribution. These results point out that ideas of spatial scaling constitute a promising framework to synthesize important hydro-ecological processes of Arnazonia. (C) 2004 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{poveda_annual_2004, author = {Poveda, G. and Salazar, L. F.}, title = {Annual and interannual (ENSO) variability of spatial scaling properties of a vegetation index (NDVI) in Amazonia}, journal = {Remote Sensing of Environment}, year = {2004}, volume = {93}, number = {3}, pages = {391--401}, url = {://WOS:000224648700009}, doi = {https://doi.org/10.1016/j.rse.2004.08.001} } |
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Poulter, B., Hattermann, F., Hawkins, E., Zaehle, S., Sitch, S., Restrepo-Coupe, N., Heyder, U. and Cramer, W. | Robust dynamics of Amazon dieback to climate change with perturbed ecosystem model parameters | 2010 | Global Change Biology Vol. 16(9), pp. 2476-2495 |
article | DOI URL |
Abstract: Climate change science is increasingly concerned with methods for managing and integrating sources of uncertainty from emission storylines, climate model projections, and ecosystem model parameterizations. In tropical ecosystems, regional climate projections and modeled ecosystem responses vary greatly, leading to a significant source of uncertainty in global biogeochemical accounting and possible future climate feedbacks. Here, we combine an ensemble of IPCC-AR4 climate change projections for the Amazon Basin (eight general circulation models) with alternative ecosystem parameter sets for the dynamic global vegetation model, LPJmL. We evaluate LPJmL simulations of carbon stocks and fluxes against flux tower and aboveground biomass datasets for individual sites and the entire basin. Variability in LPJmL model sensitivity to future climate change is primarily related to light and water limitations through biochemical and water-balance-related parameters. Temperature-dependent parameters related to plant respiration and photosynthesis appear to be less important than vegetation dynamics (and their parameters) for determining the magnitude of ecosystem response to climate change. Variance partitioning approaches reveal that relationships between uncertainty from ecosystem dynamics and climate projections are dependent on geographic location and the targeted ecosystem process. Parameter uncertainty from the LPJmL model does not affect the trajectory of ecosystem response for a given climate change scenario and the primary source of uncertainty for Amazon 'dieback' results from the uncertainty among climate projections. Our approach for describing uncertainty is applicable for informing and prioritizing policy options related to mitigation and adaptation where long-term investments are required. | |||||
BibTeX:
@article{poulter_robust_2010, author = {Poulter, B. and Hattermann, F. and Hawkins, E. and Zaehle, S. and Sitch, S. and Restrepo-Coupe, N. and Heyder, U. and Cramer, W.}, title = {Robust dynamics of Amazon dieback to climate change with perturbed ecosystem model parameters}, journal = {Global Change Biology}, year = {2010}, volume = {16}, number = {9}, pages = {2476--2495}, url = {://000280633700007}, doi = {https://doi.org/10.1111/j.1365-2486.2009.02157.x} } |
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Potter, C.S., Davidson, E.A., Klooster, S.A., Nepstad, D.C., De Negreiros, G.H. and Brooks, V. | Regional application of an ecosystem production model for studies of biogeochemistry in Brazilian Amazonia | 1998 | Global Change Biology Vol. 4(3), pp. 315-333 |
article | DOI URL |
Abstract: The degree to which primary production, soil carbon, and trace gas fluxes in tropical forests of the Amazon are limited by moisture availability and other environmental factors was examined using an ecosystem modelling application for the country of Brazil. A regional geographical information system (GIS) serves as the data source of climate drivers, satellite images, land cover, and soil properties for input to the NASA Ames-CASA (Carnegie-Ames-Stanford Approach) model over a 8-km grid resolution. Simulation results lead us to hypothesize that net primary production (NPP) is limited by cloud interception of solar radiation over the humid north-western portion of the region. Peak annual rates for NPP of nearly 1.4 kg C m(-2) year(-1) are localized in the seasonally dry eastern Amazon in areas that we assume are primarily deep-rooted evergreen forest cover. Regional effects of forest conversion on NPP and soil carbon content are indicated in the model results, especially in seasonally dry areas. Comparison of model flux predictions along selected eco-climatic transects reveal moisture, soil, and land use controls on gradients of ecosystem production and soil trace gas emissions (CO2, N2O, and NO). These results are used to formulate a series of research hypotheses for testing in the next phase of regional modelling, which includes recalibration of the light-use efficiency term in NASA-CASA using field measurements of NPP, and refinements of vegetation index and soil property (texture and potential rooting depth) maps for the region. | |||||
BibTeX:
@article{potter_regional_1998, author = {Potter, C. S. and Davidson, E. A. and Klooster, S. A. and Nepstad, D. C. and De Negreiros, G. H. and Brooks, V.}, title = {Regional application of an ecosystem production model for studies of biogeochemistry in Brazilian Amazonia}, journal = {Global Change Biology}, year = {1998}, volume = {4}, number = {3}, pages = {315--333}, url = {://WOS:000072857700008}, doi = {https://doi.org/10.1046/j.1365-2486.1998.00154.x} } |
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Potter, C., Klooster, S., Tan, P., Steinbach, M., Kumar, V. and Genovese, V. | Variability in terrestrial carbon sinks over two decades. Part III: South America, Africa, and Asia | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Seventeen years ( 1982 - 98) of net carbon flux predictions for Southern Hemisphere continents have been analyzed, based on a simulation model using satellite observations of monthly vegetation cover. The NASA Carnegie Ames Stanford Approach ( CASA) model was driven by vegetation-cover properties derived from the Advanced Very High Resolution Radiometer and radiative transfer algorithms that were developed for the Moderate Resolution Imaging Spectroradiometer ( MODIS). The terrestrial ecosystem flux for atmospheric CO2 for the Amazon region of South America has been predicted between a biosphere source of - 0.17 Pg C per year ( in 1983) and a biosphere sink of + 0.64 Pg C per year ( in 1989). The areas of highest variability in net ecosystem production (NEP) fluxes across all of South America were detected in the south-central rain forest areas of the Amazon basin and in southeastern Brazil. Similar levels of variability were recorded across central forested portions of Africa and in the southern horn of East Africa, throughout Indonesia, and in eastern Australia. It is hypothesized that periodic droughts and wildfires associated with four major El Nino events during the 1980s and 1990s have held the net ecosystem carbon sink for atmospheric CO2 in an oscillating pattern of a 4-6-yr cycle, despite observations of increasing net plant carbon fixation over the entire 17-yr time period. | |||||
BibTeX:
@article{potter_variability_2005, author = {Potter, C. and Klooster, S. and Tan, P. and Steinbach, M. and Kumar, V. and Genovese, V.}, title = {Variability in terrestrial carbon sinks over two decades. Part III: South America, Africa, and Asia}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241358700001} } |
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Potter, C., Klooster, S., Steinbach, M., Tan, P.N., Kumar, V., Shekhar, S. and De Carvalho, C.R. | Understanding global teleconnections of climate to regional model estimates of Amazon ecosystem carbon fluxes | 2004 | Global Change Biology Vol. 10(5), pp. 693-703 |
article | DOI URL |
Abstract: We have investigated global teleconnections of climate to regional satellite-driven observations for prediction of Amazon ecosystem production, in the form of monthly estimates of net carbon exchange over the period 1982-1998 from the NASA-CASA (Carnegie-Ames-Stanford) biosphere model. This model is driven by observed surface climate and monthly estimates of vegetation leaf area index (LAI) and fraction of absorbed PAR (fraction of photosynthetically active radiation, FPAR) generated from the NOAA satellite advanced very high-resolution radiometer (AVHRR) and similar sensors. Land surface AVHRR data processing using modified moderate-resolution imaging spectroradiometer radiative transfer algorithms includes improved calibration for intra- and intersensor variations, partial atmospheric correction for gaseous absorption and scattering, and correction for stratospheric aerosol effects associated with volcanic eruptions. Results from our analysis suggest that anomalies of net primary production and net ecosystem production predicted from the NASA-CASA model over large areas of the Amazon region east of 60degreesW longitude are strongly correlated with the Southern Oscillation index. Extensive areas of the south-central Amazon show strong linkages of the FPAR and the NASA-CASA anomaly record to the Arctic Oscillation index, which help confirm a strong relation to southern Atlantic climate anomalies, with associated impacts on Amazon rainfall patterns. Processes are investigated for these teleconnections of global climate to Amazon ecosystem carbon fluxes and regional land surface climate. | |||||
BibTeX:
@article{potter_understanding_2004, author = {Potter, C. and Klooster, S. and Steinbach, M. and Tan, P. N. and Kumar, V. and Shekhar, S. and De Carvalho, C. R.}, title = {Understanding global teleconnections of climate to regional model estimates of Amazon ecosystem carbon fluxes}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {693--703}, url = {://WOS:000221421600012}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00752.x} } |
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Potter, C., Klooster, S., Huete, A., Genovese, V., Bustamante, M., Ferreira, L.G., de Oliveira Jr., R.C. and Zepp, R. | Terrestrial carbon sinks in the Brazilian Amazon and Cerrado region predicted from MODIS satellite data and ecosystem modeling | 2009 | Biogeosciences Vol. 6(6), pp. 937-945 |
article | URL |
Abstract: A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of Brazilian Amazon and Cerrado regions over the period 2000-2004. Net ecosystem production (NEP) flux for atmospheric CO(2) in the region for these years was estimated. Consistently high carbon sink fluxes in terrestrial ecosystems on a yearly basis were found in the western portions of the states of Acre and Rondonia and the northern portions of the state of Para. These areas were not significantly impacted by the 2002-2003 El Nino event in terms of net annual carbon gains. Areas of the region that show periodically high carbon source fluxes from terrestrial ecosystems to the atmosphere on yearly basis were found throughout the state of Maranhno and the southern portions of the state of Amazonas. As demonstrated though tower site comparisons, NEP modeled with monthly MODIS Enhanced Vegetation Index (EVI) inputs closely resembles the measured seasonal carbon fluxes at the LBA Tapajos tower site. Modeling results suggest that the capacity for use of MODIS Enhanced Vegetation Index (EVI) data to predict seasonal uptake rates of CO(2) in Amazon forests and Cerrado woodlands is strong. | |||||
BibTeX:
@article{potter_terrestrial_2009, author = {Potter, C. and Klooster, S. and Huete, A. and Genovese, V. and Bustamante, M. and Ferreira, L. Guimaraes and de Oliveira, Jr., R. C. and Zepp, R.}, title = {Terrestrial carbon sinks in the Brazilian Amazon and Cerrado region predicted from MODIS satellite data and ecosystem modeling}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {6}, pages = {937--945}, url = {://WOS:000267543100001} } |
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Potter, C., Klooster, S., Hiatt, C., Genovese, V. and Castilla-Rubio, J.C. | Changes in the carbon cycle of Amazon ecosystems during the 2010 drought | 2011 | Environmental Research Letters Vol. 6(3) |
article | DOI URL |
Abstract: Satellite remote sensing was combined with the NASA-CASA (Carnegie Ames Stanford Approach) carbon cycle simulation model to evaluate the impact of the 2010 drought (July through September) throughout tropical South America. Results indicated that net primary production in Amazon forest areas declined by an average of 7% in 2010 compared to 2008. This represented a loss of vegetation CO(2) uptake and potential Amazon rainforest growth of nearly 0.5 Pg C in 2010. The largest overall decline in ecosystem carbon gains by land cover type was predicted for closed broadleaf forest areas of the Amazon river basin, including a large fraction of regularly flooded forest areas. Model results support the hypothesis that soil and dead wood carbon decomposition fluxes of CO(2) to the atmosphere were elevated during the drought period of 2010 in periodically flooded forest areas, compared to those for forests outside the main river floodplains. | |||||
BibTeX:
@article{potter_changes_2011, author = {Potter, Christopher and Klooster, Steven and Hiatt, Cyrus and Genovese, Vanessa and Castilla-Rubio, Juan Carlos}, title = {Changes in the carbon cycle of Amazon ecosystems during the 2010 drought}, journal = {Environmental Research Letters}, year = {2011}, volume = {6}, number = {3}, url = {://WOS:000295327900027 http://iopscience.iop.org/1748-9326/6/3/034024/pdf/1748-9326_6_3_034024.pdf}, doi = {https://doi.org/10.1088/1748-9326/6/3/034024} } |
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Potter, C., Klooster, S. and Genovese, V. | Net primary production of terrestrial ecosystems from 2000 to 2009 [BibTeX] |
2012 | Climatic Change, pp. DOI 10.1007/s10584-012-0460-2 | article | |
BibTeX:
@article{potter_net_2012, author = {Potter, C. and Klooster, S. and Genovese, V.}, title = {Net primary production of terrestrial ecosystems from 2000 to 2009}, journal = {Climatic Change}, year = {2012}, pages = {DOI 10.1007/s10584--012--0460--2} } |
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Potter, C., Klooster, S. and Genovese, V. | Carbon emissions from deforestation in the Brazilian Amazon Region | 2009 | Biogeosciences Vol. 6(11), pp. 2369-2381 |
article | URL |
Abstract: A simulation model based on satellite observations of monthly vegetation greenness from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of Brazilian Amazon and Cerrado regions over the period 2000-2002. The NASA-CASA (Carnegie Ames Stanford Approach) model estimates of annual forest production were used for the first time as the basis to generate a prediction for the standing pool of carbon in above-ground biomass (AGB; gC m(-2)) for forested areas of the Brazilian Amazon region. Plot-level measurements of the residence time of carbon in wood in Amazon forest from Malhi et al. (2006) were interpolated by inverse distance weighting algorithms and used with CASA to generate a new regional map of AGB. Data from the Brazilian PRODES (Estimativa do Desflorestamento da Amazonia) project were used to map deforested areas. Results show that net primary production (NPP) sinks for carbon varied between 4.25 Pg C yr(-1) (1 Pg=10(15) g) and 4.34 Pg C for the region and were highest across the eastern and northern Amazon areas, whereas deforestation sources of CO(2) flux from decomposition of residual woody debris were higher and less seasonal in the central Amazon than in the eastern and southern areas. Increased woody debris from past deforestation events was predicted to alter the net ecosystem carbon balance of the Amazon region to generate annual CO(2) source fluxes at least two times higher than previously predicted by CASA modeling studies. Variations in climate, land cover, and forest burning were predicted to release carbon at rates of 0.5 to 1 PgC yr(-1) from the Brazilian Amazon. When direct deforestation emissions of CO(2) from forest burning of between 0.2 and 0.6 Pg C yr(-1) in the Legal Amazon are overlooked in regional budgets, the year-to-year variations in this net biome flux may appear to be large, whereas our model results implies net biome fluxes had actually been relatively consistent from year to year during the period 2000-2002. This is the first study to use MODIS data to model all carbon pools (wood, leaf, root) dynamically in simulations of Amazon forest deforestation from clearing and burning of all kinds. | |||||
BibTeX:
@article{potter_carbon_2009, author = {Potter, C. and Klooster, S. and Genovese, V.}, title = {Carbon emissions from deforestation in the Brazilian Amazon Region}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {11}, pages = {2369--2381}, url = {://WOS:000272232200003} } |
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Potter, C., Klooster, S., de Carvalho, C.R., Genovese, V.B., Torregrosa, A., Dungan, J., Bobo, M. and Coughlan, J. | Modeling seasonal and interannual variability in ecosystem carbon cycling for the Brazilian Amazon region | 2001 | Journal of Geophysical Research-Atmospheres Vol. 106(D10), pp. 10423-10446 |
article | DOI URL |
Abstract: Previous field measurements have implied that undisturbed Amazon forests may represent a substantial terrestrial sink for atmospheric carbon dioxide. We investigated this hypothesis using a regional ecosystem model for net primary production (NPP) and soil biogeochemical cycling. Seasonal and interannual controls on net ecosystem production (NEP) were studied with integration of high-resolution (8-km) multiyear satellite data to characterize Amazon land surface properties over time. Background analysis of temporal and spatial relationships between regional rainfall patterns and satellite observations (for vegetation land cover, fire counts, and smoke aerosol effects) reveals several notable patterns in the model driver data. Autocorrelation analysis for monthly vegetation "greenness" index (normalized difference vegetation index, NDVI) from the advanced very high resolution radiometer (AVHRR) and monthly rainfall indicates a significant lag time correlation of up to 12 months. At lag times approaching 36 months, autocorrelation function (ACF) values did not exceed the 95% confidence interval at locations west of about 47 degreesW, which is near the transition zone of seasonal tropical forest and other (nonforest) vegetation types. Even at lag times of 12 months or less, the location near Manaus (approximately 60 degreesW) represents the farthest western point in the Amazon region where seasonality of rainfall accounts significantly for monthly variations in forest phenology, as observed using NDVI. Comparisons of NDVI seasonal profiles in areas of the eastern Amazon widely affected by fires (as observed from satellite) suggest that our adjusted AVHRR-NDVI captures year-to-year variation in land cover greenness with minimal interference from small fires and smoke aerosols. Ecosystem model results using this newly generated combination of regional forcing data from satellite suggest that undisturbed Amazon forests can be strong net sinks for atmospheric carbon dioxide, particularly during wet (non El Nino) years. However, drought effects during El Nino years can reduce NPP in primary forests of the eastern Amazon by 10-20%, compared to long-term average estimates of regional productivity. Annual NEP for the region is predicted to range from -0.4 Pg C yr(-1) (net CO2 source) to 0.5 Pg C yr (-1) (net CO2 sink), with large interannual variability over the states of Para, Maranhao, and Amazonas. As in the case of predicted NPP, it appears that periods of relatively high solar surface irradiance combined with several months of adequate rainfall are required to sustain the forest carbon sink for positive yearly NEP estimates. | |||||
BibTeX:
@article{potter_modeling_2001, author = {Potter, C. and Klooster, S. and de Carvalho, C. R. and Genovese, V. B. and Torregrosa, A. and Dungan, J. and Bobo, M. and Coughlan, J.}, title = {Modeling seasonal and interannual variability in ecosystem carbon cycling for the Brazilian Amazon region}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2001}, volume = {106}, number = {D10}, pages = {10423--10446}, url = {://WOS:000168839900023}, doi = {https://doi.org/10.1029/2000jd900563} } |
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Potter, C., Genovese, V.B., Klooster, S., Bobo, M. and Torregrosa, A. | Biomass burning losses of carbon estimated from ecosystem modeling and satellite data analysis for the Brazilian Amazon region | 2001 | Atmospheric Environment Vol. 35(10), pp. 1773-1781 |
article | DOI URL |
Abstract: To produce a new daily record of gross carbon emissions from biomass burning events and post-burning decomposition fluxes in the states of the Brazilian Legal Amazon (Instituto Brasileiro de Geografia e Estatistica (IBGE), 1991. Anuario Estatistico do Brasil, Vol. 51. Rio de Janeiro, Brazil pp. 1-1024). We have used vegetation greenness estimates from satellite images as inputs to a terrestrial ecosystem production model. This carbon allocation model generates new estimates of regional aboveground vegetation biomass at 8-km resolution. The modeled biomass product is then combined for the first time with fire pixel counts from the advanced very high-resolution radiometer (AVHRR) to overlay regional burning activities in the Amazon. Results from our analysis indicate that carbon emission estimates from annual region-wide sources of deforestation and biomass burning in the early 1990s are apparently three to five times higher than reported in previous studies for the Brazilian Legal Amazon (Houghton et al., 2000. Nature 403, 301-304; Fearnside, 1997. Climatic Change 35, 321-360), i.e., studies which implied that the Legal Amazon region tends toward a net-zero annual source of terrestrial carbon. In contrast, our analysis implies that the total source fluxes over the entire Legal Amazon region range from 0.2 to 1.2Pg Cyr(-1), depending strongly on annual rainfall patterns. The reasons for our higher burning emission estimates are (1) use of combustion fractions typically measured during Amazon forest burning events for computing carbon losses, (2) more detailed geographic distribution of vegetation biomass and daily fire activity for the region, and (3) inclusion of fire effects in extensive areas of the Legal Amazon covered by open woodland, secondary forests, savanna, and pasture vegetation. The total area of rainforest estimated annually to be deforested did not differ substantially among the previous analyses cited and our own. Published by Elsevier Science Ltd. | |||||
BibTeX:
@article{potter_biomass_2001, author = {Potter, C. and Genovese, V. B. and Klooster, S. and Bobo, M. and Torregrosa, A.}, title = {Biomass burning losses of carbon estimated from ecosystem modeling and satellite data analysis for the Brazilian Amazon region}, journal = {Atmospheric Environment}, year = {2001}, volume = {35}, number = {10}, pages = {1773--1781}, url = {://WOS:000167745600006}, doi = {https://doi.org/10.1016/s1352-2310(00)00459-3} } |
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Potter, C., Davidson, E., Nepstad, D. and de Carvalho, C.R. | Ecosystem modeling and dynamic effects of deforestation on trace gas fluxes in Amazon tropical forests | 2001 | Forest Ecology and Management Vol. 152(1-3), pp. 97-117 |
article | DOI URL |
Abstract: To improve predictive capabilities for water, carbon, and nitrogen gas fluxes in the Amazon region, we evaluated the performance of the NASA-CASA simulation model for tropical ecosystem biogeochemistry against independent flux measurements from two Amazon forest sites located in the Brazilian states of Rondonia and Para. Refinements of this ecosystem model include stand water balance equations, moisture holding and retention capacity for Amazon soils, and addition of a dynamic deforestation sequence to include land use change as a factor in simulations of tropical ecosystem fluxes. Results suggest that model predictions for evapotranspiration and soil water content are consistent with the overall range and seasonal changes in measured values at the two forest sites selected as test cases. The predicted carbon balance from the model implies that relatively undisturbed Amazon forest ecosystems may be large net sinks for atmospheric carbon, with annual net ecosystem production values on the order of 200 g C m(-2) per year. Measured fluxes of soil N2O for the two Amazon forests closely match our model prediction for the Para forest, but not for the Rondonia site, suggesting that process algorithms controlling nitrogen trace gas fluxes, particularly in relatively sandy tropical soils will require further study. In terms of net ecosystem carbon fluxes during deforestation and for 2 years afterward, the model predicts that these sites switch from being a net sink for carbon to a substantial source following the large loss of biomass from simulated burning. During crop regrowth simulation in the first year after deforestation, the net source of carbon to the atmosphere is nearly 1.6 kg C m(-2) per year, a flux magnitude roughly equivalent to 10 years of undisturbed CO2 sink fluxes in the Amazon forest. Compared to the primary forest that was cut and burned, predicted changes in soil nitrogen cycling lead to a doubling in annual emissions of N2O gas during the first year following deforestation, with lower emissions thereafter. Implications for scaling up these model predictions to the Amazon forest region are discussed with reference to necessary improvements in land cover, land use, and soils classifications for the area. Published by Elsevier Science B.V. | |||||
BibTeX:
@article{potter_ecosystem_2001, author = {Potter, C. and Davidson, E. and Nepstad, D. and de Carvalho, C. R.}, title = {Ecosystem modeling and dynamic effects of deforestation on trace gas fluxes in Amazon tropical forests}, journal = {Forest Ecology and Management}, year = {2001}, volume = {152}, number = {1-3}, pages = {97--117}, url = {://WOS:000171497800008}, doi = {https://doi.org/10.1016/s0378-1127(00)00593-4} } |
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Poschl, U., Williams, J., Hoor, P., Fischer, H., Crutzen, P.J., Warneke, C., Holzinger, R., Hansel, A., Jordan, A., Lindinger, W., Scheeren, H.A., Peters, W. and Lelieveld, J. | High acetone concentrations throughout the 0-12 km altitude range over the tropical rainforest in Surinam | 2001 | Journal of Atmospheric Chemistry Vol. 38(2), pp. 115-132 |
article | DOI URL |
Abstract: Airborne measurements of acetone were performed over the tropical rainforest in Surinam (2 degrees -7 degrees N, 54 degrees -58 degrees W, 0-12 km altitude) during the LBA-CLAIRE campaign in March 1998, using a novel proton transfer reaction mass spectrometer (PTR-MS) that enables the on-line monitoring of volatile organic compounds (VOC) with a higher proton affinity than water. The measured acetone volume mixing ratios ranged from similar to0.1 nmol/mol up to similar to8 nmol/mol with an overall average of 2.6 nmol/mol and a standard deviation of 1.0 nmol/mol. The observed altitude profile and correlations with CO, acetonitrile, propane and wind direction are discussed with respect to potential acetone sources. No linear correlation between acetone and CO mixing ratios was observed, at variance with results of previous measurement campaigns. The mean acetone/CO ratio (0.022) was substantially higher than typical values found before. The abundance of acetone appears to be influenced, but not dominated, by biomass burning, thus suggesting large emissions of acetone and/or acetone precursors, such as possibly 2-propanol, from living plants or decaying litter in the rainforest. | |||||
BibTeX:
@article{poschl_high_2001, author = {Poschl, U. and Williams, J. and Hoor, P. and Fischer, H. and Crutzen, P. J. and Warneke, C. and Holzinger, R. and Hansel, A. and Jordan, A. and Lindinger, W. and Scheeren, H. A. and Peters, W. and Lelieveld, J.}, title = {High acetone concentrations throughout the 0-12 km altitude range over the tropical rainforest in Surinam}, journal = {Journal of Atmospheric Chemistry}, year = {2001}, volume = {38}, number = {2}, pages = {115--132}, url = {://WOS:000166865500001}, doi = {https://doi.org/10.1023/a:1006370600615} } |
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Pontius Jr., R.G., Walker, R., Yao-Kumah, R., Arima, E., Aldrich, S., Caldas, M. and Vergara, D. | Accuracy assessment for a simulation model of Amazonian deforestation | 2007 | Annals of the Association of American Geographers Vol. 97(4), pp. 677-695 |
article | DOI URL |
Abstract: This article describes a quantitative assessment of the output from the Behavioral Landscape Model (BLM), which has been developed to simulate the spatial pattern of deforestation (i.e. forest fragmentation) in the Amazon basin in a manner consistent with human behavior. The assessment consists of eighteen runs for a section of the Transamazon Highway in the lower basin, where the BLM's simulated deforestation map for each run is compared to a reference map of 1999. The BLM simulates the transition from forest to non-forest in a spatially explicit manner in 20-m x 20-m pixels. The pixels are nested within a hierarchical stratification structure of household lots within larger development rectangles that emanate from the Transamazon Highway. Each of the eighteen runs derives from a unique combination of three model parameters. We have derived novel methods of assessment to consider (1) the nested stratification structure, (2) multiple resolutions, (3) a simpler model that predicts deforestation near the highway, (4) a null model that predicts forest persistence, and (5) a uniform model that has accuracy equal to the expected accuracy of a random spatial allocation. Results show that the model's specification of the overall quantity of non-forest is the most important factor that constrains and correlates with accuracy. A large source of location agreement is the BLM's assumption that deforestation within household lots occurs near roads. A large source of location disagreement is the BLM's less than perfect ability to simulate the proportion of deforestation by household lot. This article discusses implications of these results in the context of land change science and dynamic simulation modeling. | |||||
BibTeX:
@article{pontius_accuracy_2007, author = {Pontius, Jr., Robert Gilmore and Walker, Robert and Yao-Kumah, Robert and Arima, Eugenio and Aldrich, Stephen and Caldas, Marcellus and Vergara, Dante}, title = {Accuracy assessment for a simulation model of Amazonian deforestation}, journal = {Annals of the Association of American Geographers}, year = {2007}, volume = {97}, number = {4}, pages = {677--695}, url = {://WOS:000250938600002}, doi = {https://doi.org/10.1111/j.1467-8306.2007.00577.x} } |
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Pongratz, J., Bounoua, L., DeFries, R.S., Morton, D.C., Anderson, L.O., Mauser, W. and Klink, C.A. | The impact of land cover change on surface energy and water balance in Mato Grosso, Brazil | 2006 | Earth Interactions Vol. 10 |
article | URL |
Abstract: The sensitivity of surface energy and water fluxes to recent land cover changes is simulated for a small region in northern Mato Grosso, Brazil. The Simple Biosphere Model (SiB2) is used, driven by biophysical parameters derived from the Moderate Resolution Imaging Spectroradiometer ( MODIS) at 250-m resolution, to compare the effects of different land conversion types. The mechanisms through which changes in vegetation alter surface fluxes of energy, momentum, water, and carbon are analyzed for both wet and dry seasons. It is found that morphological changes contribute to warming and drying of the atmosphere while physiological changes, particularly those associated with a plant's photosynthetic pathway, counterbalance or exacerbate the warming depending on the type of conversion and the season. Furthermore, this study's results indicate that initial clearing of evergreen and transition forest to bare ground increases canopy temperature by up to 1.7 degrees C. For subsequent land use such as pasture or cropland, the largest effect is seen for the conversion of evergreen forest to C3 cropland during the wet season, with a 21% decrease of the latent heat flux and 0.4 degrees C increase in canopy temperature. The secondary conversion of pasture to cropland resulted in slight warming and drying during the wet season driven mostly by the change in carbon pathway from C4 to C3. For all conversions types, the daily temperature range is amplified, suggesting that plants replacing forest clearing require more temperature tolerance than the trees they replace. The results illustrate that the effect of deforestation on climate depends not only on the overall extent of clearing but also on the subsequent land use type. | |||||
BibTeX:
@article{pongratz_impact_2006, author = {Pongratz, Julia and Bounoua, Lahouari and DeFries, Ruth S. and Morton, Douglas C. and Anderson, Liana O. and Mauser, Wolfram and Klink, Carlos A.}, title = {The impact of land cover change on surface energy and water balance in Mato Grosso, Brazil}, journal = {Earth Interactions}, year = {2006}, volume = {10}, url = {://WOS:000243164700001} } |
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Ponczek, M., Franco, M.A., Carbone, S., Rizzo, L.V., Monteiro dos Santos, D., Morais, F.G., Duarte, A., Barbosa, H.M.J. and Artaxo, P. | Linking the chemical composition and optical properties of biomass burning aerosols in Amazonia | 2022 | Environmental Science: Atmospheres Vol. 2(2), pp. 252-269 |
article | DOI URL |
Abstract: Biomass burning emissions in Amazonia change the atmospheric composition and aerosol properties during the dry season. We investigated fine-mode aerosol chemical composition and optical properties with an intensive field experiment in the dry-to-wet season transition in 2018 in Southwestern Amazonia. Aerosol composition and physical properties were measured using ACSMs, aethalometers, nephelometers, SMPSs, and CPCs. PM1 mass concentrations showed a mean value of 12.4 ± 10.1 μg m−3. Organic matter was the major constituent of PM1, contributing more than 75%, whereas black carbon (BC) contributed ∼15%, and inorganics were less than 10%. The organic fraction of PM1 was apportioned by positive-matrix factorization (PMF), resolving 4 organic aerosol (OA) factors: two oxygenated OAs (OOA-1 and OOA-2), one hydrocarbon-like (HOA), and one biomass burning OA (BBOA). A low single scattering albedo (637 nm) of 0.77 ± 0.08 was observed, suggesting a significant absorption material. BC and brown carbon (BrC) contributions to the absorption coefficient (470 nm) were retrieved, and BrC corresponded, on average, to 20% of total absorption. The mass scattering (MSE) and absorption efficiencies (MAE) of PM1 particles were determined by multilinear regression (MLR), using the PMF factors as predictor variables. Overall, organic aerosols showed significant light absorption in the UV-vis wavelength range and strong spectral dependence indicating the presence of organic species that act as BrC, predominantly associated with biomass burning OAs. Our results emphasize the need for a better understanding of links between aerosol composition and optical properties, including the absorption spectra of BrC in the Amazon. | |||||
BibTeX:
@article{ponczek_linking_2022, author = {Ponczek, Milena and Franco, Marco A. and Carbone, Samara and Rizzo, Luciana V. and Monteiro dos Santos, Djacinto and Morais, Fernando G. and Duarte, Alejandro and Barbosa, Henrique M. J. and Artaxo, Paulo}, title = {Linking the chemical composition and optical properties of biomass burning aerosols in Amazonia}, journal = {Environmental Science: Atmospheres}, year = {2022}, volume = {2}, number = {2}, pages = {252--269}, url = {http://dx.doi.org/10.1039/D1EA00055A}, doi = {https://doi.org/10.1039/D1EA00055A} } |
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Polezer, G., Oliveira, A., Potgieter-Vermaak, S., Godoi, A.F.L., de Souza, R.A.F., Yamamoto, C.I., Andreoli, R.V., Medeiros, A.S., Machado, C.M.D., dos Santos, E.O., de André, P.A., Pauliquevis, T., Saldiva, P.H.N., Martin, S.T. and Godoi, R.H.M. | The influence that different urban development models has on PM2.5 elemental and bioaccessible profiles | 2019 | Scientific Reports Vol. 9(1), pp. 14846 |
article | DOI URL |
Abstract: Limited studies have reported on in-vitro analysis of PM2.5 but as far as the authors are aware, bioaccessibility of PM2.5 in artificial lysosomal fluid (ALF) has not been linked to urban development models before. The Brazilian cities Manaus (Amazon) and Curitiba (South region) have different geographical locations, climates, and urban development strategies. Manaus drives its industrialization using the free trade zone policy and Curitiba adopted a services centered economy driven by sustainability. Therefore, these two cities were used to illustrate the influence that these different models have on PM2.5 in vitro profile. We compared PM2.5 mass concentrations and the average total elemental and bioaccessible profiles for Cu, Cr, Mn, and Pb. The total average elemental concentrations followed Mn textgreater Pb textgreater Cu textgreater Cr in Manaus and Pb textgreater Mn textgreater Cu textgreater Cr in Curitiba. Mn had the lowest solubility while Cu showed the highest bioaccessibility (100%) and was significantly higher in Curitiba than Manaus. Cr and Pb had higher bioaccessibility in Manaus than Curitiba. Despite similar mass concentrations, the public health risk in Manaus was higher than in Curitiba indicating that the free trade zone had a profound effect on the emission levels and sources of airborne PM. These findings illustrate the importance of adopting sustainable air quality strategies in urban planning. | |||||
BibTeX:
@article{polezer_influence_2019, author = {Polezer, Gabriela and Oliveira, Andrea and Potgieter-Vermaak, Sanja and Godoi, Ana F. L. and de Souza, Rodrigo A. F. and Yamamoto, Carlos I. and Andreoli, Rita V. and Medeiros, Adan S. and Machado, Cristine M. D. and dos Santos, Erickson O. and de André, Paulo A. and Pauliquevis, Theotonio and Saldiva, Paulo H. N. and Martin, Scot T. and Godoi, Ricardo H. M.}, title = {The influence that different urban development models has on PM2.5 elemental and bioaccessible profiles}, journal = {Scientific Reports}, year = {2019}, volume = {9}, number = {1}, pages = {14846}, url = {https://doi.org/10.1038/s41598-019-51340-4}, doi = {https://doi.org/10.1038/s41598-019-51340-4} } |
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Pöhlker, M.L., Pöhlker, C., Klimach, T., Angelis, I.H.d., Barbosa, H.M.J., Brito, J., Carbone, S., Cheng, Y., Chi, X., Ditas, F., Ditz, R., Gunthe, S.S., Kesselmeier, J., Könemann, T., Lavrič, J.V., Martin, S.T., Moran-Zuloaga, D., Rose, D., Saturno, J., Su, H., Thalman, R., Walter, D., Wang, J., Wolff, S., Artaxo, P., Andreae, M.O. and Pöschl, U. | Long-term observations of atmospheric aerosol, cloud condensation nuclei concentration and hygroscopicity in the Amazon rain forest – Part 1: Size-resolved characterization and new model parameterizations for CCN prediction [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 15709-15740 |
article | DOI |
BibTeX:
@article{pohlker_long-term_2016, author = {Pöhlker, Mira L. and Pöhlker, Christopher and Klimach, Thomas and Angelis, Isabella Hrabe de and Barbosa, Henrique M. J. and Brito, Joel and Carbone, Samara and Cheng, Yafang and Chi, Xuguang and Ditas, Florian and Ditz, Reiner and Gunthe, Sachin S. and Kesselmeier, Jürgen and Könemann, Tobias and Lavrič, Jošt V. and Martin, Scot T. and Moran-Zuloaga, Daniel and Rose, Diana and Saturno, Jorge and Su, Hang and Thalman, Ryan and Walter, David and Wang, Jian and Wolff, Stefan and Artaxo, Paulo and Andreae, Meinrat O. and Pöschl, Ulrich}, title = {Long-term observations of atmospheric aerosol, cloud condensation nuclei concentration and hygroscopicity in the Amazon rain forest – Part 1: Size-resolved characterization and new model parameterizations for CCN prediction}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {15709--15740}, doi = {https://doi.org/10.5194/acp-16-15709-2016} } |
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Pöhlker Ditas, F.S.J.K.T.H.d.A.I.A.A.C.B.J.C.S.C.Y.C.X.D.R.G.S.S.H.B.A.K.K.K.J.K.T.K.O.O.L.J.V.M.S.T.M.E.M.-Z.D.R.L.V.R.D.S.H.T.R.W.D.W.J.W.S.B.H.M.J.A.P.A.M.O.P.U.and.P.C.M.L. | Long-term observations of cloud condensation nuclei over the Amazon rain forest – Part 2: Variability and characteristics of biomass burning, long-range transport, and pristine rain forest aerosols [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 10289-10331 |
article | DOI |
BibTeX:
@article{pohlker_long-term_2018, author = {Pöhlker, Ditas, F., Saturno, J., Klimach, T., Hrabě de Angelis, I., Araùjo, A. C., Brito, J., Carbone, S., Cheng, Y., Chi, X., Ditz, R., Gunthe, S. S., Holanda, B. A., Kandler, K., Kesselmeier, J., Könemann, T., Krüger, O. O., Lavrič, J. V., Martin, S. T., Mikhailov, E., Moran-Zuloaga, D., Rizzo, L. V., Rose, D., Su, H., Thalman, R., Walter, D., Wang, J., Wolff, S., Barbosa, H. M. J., Artaxo, P., Andreae, M. O., Pöschl, U., and Pöhlker, C.:, M. L.}, title = {Long-term observations of cloud condensation nuclei over the Amazon rain forest – Part 2: Variability and characteristics of biomass burning, long-range transport, and pristine rain forest aerosols}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {10289--10331}, doi = {https://doi.org/10.5194/acp-18-10289-2018} } |
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Pöhlker, C., Wiedemann, K.T., Sinha, B., Shiraiwa, M., Gunthe, S.S., Smith, M., Su, H., Artaxo, P., Chen, Q., Cheng, Y., Elbert, W., Gilles, M., Kilcoyne, A., Moffer, R., Weigand, M., Martin, S., Pöschl, U. and Andreae, M.O. | Biogenic Potassium Salt Particles as Seeds for Secondary Organic Aerosol in the Amazon [BibTeX] |
2012 | Science Vol. 337(6098), pp. 1075-1078 |
article | |
BibTeX:
@article{pohlker_biogenic_2012, author = {Pöhlker, C. and Wiedemann, K. T. and Sinha, B. and Shiraiwa, M. and Gunthe, S. S. and Smith, M. and Su, H. and Artaxo, P. and Chen, Q. and Cheng, Y. and Elbert, W. and Gilles, M.K. and Kilcoyne, A.L.D. and Moffer, R.C. and Weigand, M. and Martin, S.T. and Pöschl, U. and Andreae, M. O.}, title = {Biogenic Potassium Salt Particles as Seeds for Secondary Organic Aerosol in the Amazon}, journal = {Science}, year = {2012}, volume = {337}, number = {6098}, pages = {1075--1078} } |
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Pöhlker, C., Walter, D., Paulsen, H., Könemann, T., Rodríguez-Caballero, E., Moran-Zuloaga, D., Brito, J., Carbone, S., Degrendele, C., Després, V.R., Ditas, F., Holanda, B.A., Kaiser, J.W., Lammel, G., Lavrič, J.V., Ming, J., Pickersgill, D., Pöhlker, M.L., Praß, M., Löbs, N., Saturno, J., Sörgel, M., Wang, Q., Weber, B., Wolff, S., Artaxo, P., Pöschl, U. and Andreae, M.O. | Land cover and its transformation in the backward trajectory footprint region of the Amazon Tall Tower Observatory [BibTeX] |
2019 | Atmos. Chem. Phys. Vol. 19(13), pp. 8425-8470 |
article | DOI URL |
BibTeX:
@article{pohlker_land_2019, author = {Pöhlker, C. and Walter, D. and Paulsen, H. and Könemann, T. and Rodríguez-Caballero, E. and Moran-Zuloaga, D. and Brito, J. and Carbone, S. and Degrendele, C. and Després, V. R. and Ditas, F. and Holanda, B. A. and Kaiser, J. W. and Lammel, G. and Lavrič, J. V. and Ming, J. and Pickersgill, D. and Pöhlker, M. L. and Praß, M. and Löbs, N. and Saturno, J. and Sörgel, M. and Wang, Q. and Weber, B. and Wolff, S. and Artaxo, P. and Pöschl, U. and Andreae, M. O.}, title = {Land cover and its transformation in the backward trajectory footprint region of the Amazon Tall Tower Observatory}, journal = {Atmos. Chem. Phys.}, year = {2019}, volume = {19}, number = {13}, pages = {8425--8470}, url = {https://acp.copernicus.org/articles/19/8425/2019/}, doi = {https://doi.org/10.5194/acp-19-8425-2019} } |
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Pöhlker, C., Saturno, J., Krüger, M.L., Förster, J.-D., Weigand, M., Wiedemann, K.T., Bechtel, M., Artaxo, P. and Andreae, M.O. | Efflorescence upon humidification? X-ray microspectroscopic in situ observation of changes in aerosol microstructure and phase state upon hydration [BibTeX] |
2014 | Geophysical Research Letters Vol. 41 |
article | DOI |
BibTeX:
@article{pohlker_efflorescence_2014, author = {Pöhlker, Christopher and Saturno, Jorge and Krüger, Mira L. and Förster, Jan-David and Weigand, Markus and Wiedemann, Kenia T. and Bechtel, Michael and Artaxo, Paulo and Andreae, Meinrat O.}, title = {Efflorescence upon humidification? X-ray microspectroscopic in situ observation of changes in aerosol microstructure and phase state upon hydration}, journal = {Geophysical Research Letters}, year = {2014}, volume = {41}, doi = {https://doi.org/10.1002/2014GL059409} } |
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Poeschl, U., Martin, S.T., Sinha, B., Chen, Q., Gunthe, S.S., Huffman, J.A., Borrmann, S., Farmer, D.K., Garland, R.M., Helas, G., Jimenez, J.L., King, S.M., Manzi, A., Mikhailov, E., Pauliquevis, T., Petters, M.D., Prenni, A.J., Roldin, P., Rose, D., Schneider, J., Su, H., Zorn, S.R., Artaxo, P. and Andreae, M.O. | Rainforest Aerosols as Biogenic Nuclei of Clouds and Precipitation in the Amazon | 2010 | Science Vol. 329(5998), pp. 1513-1516 |
article | DOI URL |
Abstract: The Amazon is one of the few continental regions where atmospheric aerosol particles and their effects on climate are not dominated by anthropogenic sources. During the wet season, the ambient conditions approach those of the pristine pre-industrial era. We show that the fine submicrometer particles accounting for most cloud condensation nuclei are predominantly composed of secondary organic material formed by oxidation of gaseous biogenic precursors. Supermicrometer particles, which are relevant as ice nuclei, consist mostly of primary biological material directly released from rainforest biota. The Amazon Basin appears to be a biogeochemical reactor, in which the biosphere and atmospheric photochemistry produce nuclei for clouds and precipitation sustaining the hydrological cycle. The prevailing regime of aerosol-cloud interactions in this natural environment is distinctly different from polluted regions. | |||||
BibTeX:
@article{poeschl_rainforest_2010, author = {Poeschl, U. and Martin, S. T. and Sinha, B. and Chen, Q. and Gunthe, S. S. and Huffman, J. A. and Borrmann, S. and Farmer, D. K. and Garland, R. M. and Helas, G. and Jimenez, J. L. and King, S. M. and Manzi, A. and Mikhailov, E. and Pauliquevis, T. and Petters, M. D. and Prenni, A. J. and Roldin, P. and Rose, D. and Schneider, J. and Su, H. and Zorn, S. R. and Artaxo, P. and Andreae, M. O.}, title = {Rainforest Aerosols as Biogenic Nuclei of Clouds and Precipitation in the Amazon}, journal = {Science}, year = {2010}, volume = {329}, number = {5998}, pages = {1513--1516}, note = {Edition: 2010/09/18}, url = {://WOS:000281869000038}, doi = {https://doi.org/10.1126/science.1191056} } |
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Piva, L.R.O., Jardine, K.J., Gimenez, B.O., Perdiz, R.d.O., Menezes, V.S., Durgante, F.M., Cobello, L.O., Higuchi, N. and Chambers, J.Q. | Volatile monoterpene ‘fingerprints’ of resinous Protium tree species in the Amazon rainforest [BibTeX] |
2019 | Phytochemistry Vol. 160, pp. 61-70 |
article | |
BibTeX:
@article{piva_volatile_2019, author = {Piva, Luani R.de O. and Jardine, Kolby J. and Gimenez, Bruno O. and Perdiz, Ricardo de Oliveira and Menezes, Valdiek S. and Durgante, Flávia M. and Cobello, Leticia O. and Higuchi, Niro and Chambers, Jeffrey Q.}, title = {Volatile monoterpene ‘fingerprints’ of resinous Protium tree species in the Amazon rainforest}, journal = {Phytochemistry}, year = {2019}, volume = {160}, pages = {61--70} } |
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Pitman, N.C.A., Mogollon, H., Davila, N., Rios, M., Garcia-Villacorta, R., Guevara, J., Baker, T.R., Monteagudo, A., Phillips, O.L., Vasquez-Martinez, R., Ahuite, M., Aulestia, M., Cardenas, D., Ceron, C.E., Loizeau, P.-A., Neill, D.A., Percy, N.V., Palacios, W.A., Spichiger, R. and Valderrama, E. | Tree community change across 700 km of lowland Amazonian forest from the Andean foothills to Brazil | 2008 | Biotropica Vol. 40(5), pp. 525-535 |
article | DOI URL |
Abstract: We describe patterns of tree community change along a 700-km transect through terra firme forests of western Amazonia, running from the base of the Andes in Ecuador to the Peru-Brazil border. Our primary question is whether floristic variation at large scales arises from many gradual changes or a few abrupt ones. Data from 54 1-ha tree plots along the transect support the latter model, showing two sharp discontinuities in community structure at the genus level. One is located near the Ecuador-Peru border, where the suite of species that dominates large areas of Ecuadorean forest declines abruptly in importance to the east. This discontinuity is underlain by a subterranean paleoarch and congruent with a change in soil texture. A second discontinuity is associated with the shift from clay to white sand soils near Iquitos. We hypothesize that the first discontinuity is part of an edaphic boundary that runs along the Andean piedmont and causes a transition from tree communities preferring richer, younger soils near the base of the Andes to those preferring poorer, older soils farther east. Because the floristic changes observed at this discontinuity are conserved for large distances to the east and west of it, the discontinuity is potentially key for understanding floristic variation in western Amazonia. The significant floristic turnover at the Ecuador-Peru border suggests that the only large protected area in the region-Ecuador's Yasuni National Park-is not adequate protection for the very diverse tree communities that cover vast areas of northern Peru. | |||||
BibTeX:
@article{pitman_tree_2008, author = {Pitman, Nigel C. A. and Mogollon, Hugo and Davila, Nallarett and Rios, Marcos and Garcia-Villacorta, Roosevelt and Guevara, Juan and Baker, Timothy R. and Monteagudo, Abel and Phillips, Oliver L. and Vasquez-Martinez, Rodolfo and Ahuite, Manuel and Aulestia, Milton and Cardenas, Dairon and Ceron, Carlos E. and Loizeau, Pierre-Andre and Neill, David A. and Percy, Nunez V. and Palacios, Walter A. and Spichiger, Rodolphe and Valderrama, Elvis}, title = {Tree community change across 700 km of lowland Amazonian forest from the Andean foothills to Brazil}, journal = {Biotropica}, year = {2008}, volume = {40}, number = {5}, pages = {525--535}, url = {://WOS:000258581100001}, doi = {https://doi.org/10.1111/j.1744-7429.2008.00424.x} } |
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Pinto-Junior, O.B., Sanches, L., Lobo, F.d.A., Brandao, A.A. and Nogueira, J.d.S. | Leaf area index of a tropical semi-deciduous forest of the southern Amazon Basin | 2011 | International Journal of Biometeorology Vol. 55(2), pp. 109-118 |
article | DOI URL |
Abstract: Leaf area index (LAI) is an important ecophysiological variable because leaves are the organs responsible for gas exchange between plants and the atmosphere. This variable can be calculated from primary values of leaf area assessed by destructive or non-destructive methods, which is relatively easy when crop species are investigated, but is not the case when the focus is on natural wood plants communities. In this paper, we analyze the seasonality of LAI estimated by three different methods in the Amazonia-savannah transitional forest, located 50 km north-east of Sinop city, Mato Grosso, Brazil. In the first method, we combine Monsi and Saekis' original method [Monsi M, Saeki T (1953) Jpn J Bot 14:22-52], which measures LAI using the Beer-Lambert extinction law, and the proposition of Goudriaan [Goudriaan J (1988) Agric For Meteorol 43:155-169] to estimate the extinction coefficient from solar height. The second method differed from the first only in the way in which the daily fraction of intercepted photosynthetic active radiation (FPAR) was calculated, as proposed by Charles-Edwards and Lawn (Charles-Edwards DA, Lawn RJ (1984) Plant Cell Environ 7:247-251]. In the third method, we used a remote sensing technique [MOD15_BU-collection 4, produced and distributed by EROS Data Center Distributed Active Archive Center (EDC DAAC)]. We found that the first and the second methods revealed the expected LAI dynamics, which increased during the dry-wet transition and wet season, and decreased during the wet-dry transition and dry season. From 20 randomly distributed sets in a 1.0 ha area, only 3 showed significant differences in LAI estimated from the first two methods; conversely, LAI was overestimated by the third method. | |||||
BibTeX:
@article{pinto-junior_leaf_2011, author = {Pinto-Junior, Osvaldo Borges and Sanches, Luciana and Lobo, Francisco de Almeida and Brandao, Adilson Amorim and Nogueira, Jose de Souza}, title = {Leaf area index of a tropical semi-deciduous forest of the southern Amazon Basin}, journal = {International Journal of Biometeorology}, year = {2011}, volume = {55}, number = {2}, pages = {109--118}, note = {Edition: 2010/06/10}, url = {://WOS:000287588400003}, doi = {https://doi.org/10.1007/s00484-010-0317-1} } |
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Pinto Júnior, O.B., Lobo, F.A., Sanches, L., Vourlitis, G.L. and Nogueira, J.d.S. | Mecanismos de controle da variação sazonal da transpiração de uma floresta de transição Amazônia Cerrado [BibTeX] |
2009 | Revista Ciência e Natura Vol. 31(2), pp. 95 - 106 |
article | |
BibTeX:
@article{pinto_junior_mecanismos_2009, author = {Pinto Júnior, Osvaldo Borges and Lobo, Francisco Almeida and Sanches, Luciana and Vourlitis, George Louis and Nogueira, José de Souza}, title = {Mecanismos de controle da variação sazonal da transpiração de uma floresta de transição Amazônia Cerrado}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {31}, number = {2}, pages = {95 -- 106} } |
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Pinto Junior Sanches, L.N.J.J.V.G.O. | Estimativa de Q10 por meio do efluxo de CO2 no solo na estação seca numa floresta tropical de transição amazônica [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 117-121 |
article | |
BibTeX:
@article{pinto_junior_estimativa_2006, author = {Pinto Junior, Sanches, L., Nogueira, J.S., J.S., Vourlitis, G.L., O.B.}, title = {Estimativa de Q10 por meio do efluxo de CO2 no solo na estação seca numa floresta tropical de transição amazônica}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {117--121} } |
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Pinto, A.d.S., Bustamante, M.M.C., da Silva, M.R.S.S., Kisselle, K.W., Brossard, M., Kruger, R., Zepp, R.G. and Burke, R.A. | Effects of different treatments of pasture restoration on soil trace gas emissions in the cerrados of central Brazil | 2006 | Earth Interactions Vol. 10 |
article | DOI URL |
Abstract: Planted pastures ( mainly Brachiaria spp) are the most extensive land use in the cerrado (savannas of central Brazil) with an area of approximately 50 x 10(6) ha. The objective of the study was to assess the effects of pasture restoration on the N dynamics ( net N mineralization/ nitrification, available inorganic N and soil N oxide gas fluxes - NO and N2O), C dynamics (CO2 fluxes and microbial biomass carbon), and diversity of the soil bacterial community using denaturing gradient gel electrophoresis (DGGE) profiles. Sampling was done monthly on a farm in Planaltina, Goias, Brazil (15 degrees 13'S, 47 degrees 42 'W) from November 2001 to April 2002. Three areas of cerradao ( dense cerrado) were converted to pasture ( Brachiaria brizantha) in 1991, and after 8 years degradation was evident with the decreasing plant biomass production. Methods to restore these pastures were investigated for their sustainability, principally their effects on trace gas emissions. The pastures have been managed since 1999 as follows: 1) fertilized plot (N = 60 kg ha(-1) yr(-1), P = 12 kg ha(-1) yr(-1)); 2) grass - legume plot, Brachiaria associated with a legume ( Stylosanthes guianensis) with addition of P (12 kg ha(-1) yr(-1)); and 3) a traditional plot without management. A fourth area of cerradao was converted to pasture in 1999 and was not managed ( young pasture). Ammonium was the predominant inorganic N form in the soils (similar to 76 mg N kg(-1)) for all treatments throughout the study. In December 2001 a reduction in average soil N-NH4+ was observed (similar to 30 mg N kg(-1)) compared to November 2001, probably related to plant demand. All plots had high variability of soil N gases emissions, but during the wet season, the NO and N2O soil fluxes were near zero. The results of the water addition experiment made during the dry season ( September 2002) indicated that the transition of dry to wet season is an important period for the production of N gases in the fertilized pasture and in the young pasture. Soil CO2 fluxes also increased after the water addition and the grass - legume plot had the highest increase in soil respiration ( from similar to 2 to 8.3 mu mol m(-2) s(-1)). The lowest values of soil respiration and microbial biomass carbon (similar to 320 mg C kg(-1) soil) tended to be observed in the young pasture, because the superficial layer of the soil ( 0 - 10 cm) was removed during the conversion to pasture. Trace gas emissions measured after the water addition experiment corresponded to rapid changes in the soil bacterial community. The young pasture sample showed the lowest level of similarity in relation to the others, indicating that the bacterial community is also influenced by the time since conversion. This study indicates that the restoration technique of including Stylosanthes guianensis with B. brizantha increases plant productivity without the peaks of N oxide gas emissions that are often associated with the use of N fertilizers. Additionally, the soil bacterial community structure may be restored to one similar to that of native cerrado grasslands, suggesting that this restoration method may beneficially affect bacterially mediated processes. | |||||
BibTeX:
@article{pinto_effects_2006, author = {Pinto, Alexandre de S. and Bustamante, Mercedes M. C. and da Silva, Maria Regina S. S. and Kisselle, Keith W. and Brossard, Michel and Kruger, Ricardo and Zepp, Richard G. and Burke, Roger A.}, title = {Effects of different treatments of pasture restoration on soil trace gas emissions in the cerrados of central Brazil}, journal = {Earth Interactions}, year = {2006}, volume = {10}, url = {://WOS:000241359300001}, doi = {https://doi.org/10.1175/ei146.1} } |
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Pinto, A.D., Bustamante, M.M.C., Kisselle, K., Burke, R., Zepp, R., Viana, L.T., Varella, R.F. and Molina, M. | Soil emissions of N(2)O, NO, and CO(2) in Brazilian Savannas: Effects of vegetation type, seasonality, and prescribed fires | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Using closed chamber techniques, soil fluxes of NO, N(2)O, and CO(2) were measured from September 1999 to November 2000 in savanna areas of central Brazil (cerrado) subjected to prescribed fires. Our studies focused on two vegetation types, cerrado stricto sensu (20-50% canopy cover) and campo sujo (open, grass dominated), which were either burned every 2 years or protected from fire. Soil moisture and vegetation type were more important in controlling NO and CO(2) fluxes than fire regime (early dry season, middle dry season or late dry season burning). N(2)O fluxes, however, were very low and below detection limit in any of the vegetation-fire treatments. NO emissions increased after burning (1.0 ng NO-N cm(-2) h(-1)), but flux returned quickly to prefire levels and even lower. In comparison, NO emissions increased 100-fold (to 10.5 ng NO-N cm(-2) h(-1)) during a water-addition experiment in unburned campo sujo, and to 1.0 ng NO-N cm(-2) h(-1) in unburned cerrado and 1.9 ng NO-N cm(-2) h(-1) in burned cerrado with the first rains. Low NO and N(2)O emissions, low nitrification rates, and the majority of inorganic N in the form of NH(4)(+) all indicate a conservative N cycle in the cerrado. CO(2) fluxes increased with the onset of the rainy season and after artificial water addition. The highest CO(2) measured in the wet season was 6.3 mumol CO(2) m(-2) s(-1) in burned campo sujo. During the dry season, soil respiration in burned and unburned treatments were similar (average flux = 1.6-2.3 m mol CO(2) m(-2) s(-1)). Differences between fire treatments of cerrado and campo sujo CO(2) fluxes are attributed to differences in relative litter production and root activity. | |||||
BibTeX:
@article{pinto_soil_2002, author = {Pinto, A. D. and Bustamante, M. M. C. and Kisselle, K. and Burke, R. and Zepp, R. and Viana, L. T. and Varella, R. F. and Molina, M.}, title = {Soil emissions of N(2)O, NO, and CO(2) in Brazilian Savannas: Effects of vegetation type, seasonality, and prescribed fires}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200110}, doi = {https://doi.org/10.1029/2001jd000342} } |
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Pinho, C.M.D.d., Amaral, S. and Escada, M.I.S. | Ocupação humana na Amazônia: A articulação e o papel das localidades na rede urbana [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 79-90 |
incollection | |
BibTeX:
@incollection{emilio_ocupacao_2014, author = {Pinho, Carolina Moutinho Duque de and Amaral, Silvana and Escada, Maria Isabel Sobral}, title = {Ocupação humana na Amazônia: A articulação e o papel das localidades na rede urbana}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {79--90}, note = {Section: 7} } |
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Pinheiro, M. and Paulo, S.d. | Utilização da análise de FOURIER no estudo de variáveis micrometeorológicas de uma floresta de transição do norte de Mato Grosso [BibTeX] |
2011 | Acta Amazonica Vol. 41(1), pp. 39 - 46 |
article | |
BibTeX:
@article{pinheiro_utilizacao_2011, author = {Pinheiro, M.R. and Paulo, S.R. de}, title = {Utilização da análise de FOURIER no estudo de variáveis micrometeorológicas de uma floresta de transição do norte de Mato Grosso}, journal = {Acta Amazonica}, year = {2011}, volume = {41}, number = {1}, pages = {39 -- 46} } |
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Pinel, S., Bonnet, M.-P., Silva, J.S.D., Moreira, D., Calmant, S., Satgé, F. and Seyler, F. | Correction of Interferometric and Vegetation Biases in the SRTMGL1 Spaceborne DEM with Hydrological Conditioning towards Improved Hydrodynamics Modeling in the Amazon Basin [BibTeX] |
2015 | Remote Sensing Vol. 7(12), pp. 16108-16130 |
article | DOI |
BibTeX:
@article{pinel_correction_2015, author = {Pinel, Sebastien and Bonnet, Marie-Paule and Silva, Joecila Santos Da and Moreira, Daniel and Calmant, Stephane and Satgé, Fredéric and Seyler, Fredérique}, title = {Correction of Interferometric and Vegetation Biases in the SRTMGL1 Spaceborne DEM with Hydrological Conditioning towards Improved Hydrodynamics Modeling in the Amazon Basin}, journal = {Remote Sensing}, year = {2015}, volume = {7}, number = {12}, pages = {16108--16130}, doi = {https://doi.org/10.3390/rs71215822} } |
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Pilotto, I., Rodrıguez, D., Tomasella, J., Sampaio, G. and Chou, S. | Comparisons of the Noah-MP land surface model simulations with measurements of forest and crop sites in Amazonia [BibTeX] |
2015 | Meteorology and Atmospheric Physics Vol. 127(6), pp. 711-723 |
article | DOI |
BibTeX:
@article{pilotto_comparisons_2015, author = {Pilotto, I.L. and Rodrıguez, D.A. and Tomasella, J. and Sampaio, G. and Chou, S.C.}, title = {Comparisons of the Noah-MP land surface model simulations with measurements of forest and crop sites in Amazonia}, journal = {Meteorology and Atmospheric Physics}, year = {2015}, volume = {127}, number = {6}, pages = {711--723}, doi = {https://doi.org/10.1007/s00703-015-0399-8} } |
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Pilotto, I.L., Rodríguez, D.A., Chan Chou, S., Tomasella, J., Sampaio, G. and Gomes, J.L. | Effects of the surface heterogeneities on the local climate of a fragmented landscape in Amazonia using a tile approach in the Eta/Noah-MP model | 2017 | Quarterly Journal of the Royal Meteorological Society Vol. 143(704), pp. 1565-1580 |
article | DOI URL |
Abstract: This study evaluates the use of tiles to estimate the effects of surface heterogeneities in simulations of local climate in a landscape-fragmented region of Amazonia. Three experiments using the Eta/Noah-MP model were designed as follows: two experiments with a spatial resolution of 5 km with and without the use of the tile approach. The third experiment used a finer spatial resolution of 2 km without the use of the tile approach (high-resolution experiment). Simulations were carried out for the rainy and dry seasons, which correspond to the months of March and September 2003, respectively. In general, the magnitude of surface fluxes is significantly affected by the introduction of tiles. In the dry season, the use of tiles in the simulation increases the magnitude of precipitation (about 7 mm day−1), skin temperature (about 4 °C), sensible heat flux (about 80 W m−2) and surface albedo (about 0.7). It reduces the latent heat flux (about 30 W m−2) and net radiation (about 40 W m−2). On the other hand, in the rainy season, the model produces excessive precipitation. This may have partly masked the signs of the land fragmentation impact. The tile experiment generates a warmer and drier boundary layer during the dry season. The impact of the surface heterogeneity representation is higher in the dry season than in the rainy season. The results suggest that the degree of impact of the subgrid process representation on the local climate is related to the spatial scale of the fragmentation. The use of the tile approach improves the representation of the effects of landscape heterogeneity on the spatial distribution of surface flux variability in fragmented areas. Comparison against measured data from flux towers in the region show that the model can simulate diurnal and seasonal variations in the local fluxes, despite the biases. | |||||
BibTeX:
@article{pilotto_effects_2017, author = {Pilotto, Isabel L. and Rodríguez, Daniel A. and Chan Chou, Sin and Tomasella, Javier and Sampaio, Gilvan and Gomes, Jorge L.}, title = {Effects of the surface heterogeneities on the local climate of a fragmented landscape in Amazonia using a tile approach in the Eta/Noah-MP model}, journal = {Quarterly Journal of the Royal Meteorological Society}, year = {2017}, volume = {143}, number = {704}, pages = {1565--1580}, url = {https://rmets.onlinelibrary.wiley.com/doi/abs/10.1002/qj.3026}, doi = {https://doi.org/10.1002/qj.3026} } |
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Piedade, V., Lopes, A., Henrique, H., Fé, L., Wittmann F., M. and Almeida-Val | Organismos aquáticos e de áreas úmidas em uma Amazônia em transição [BibTeX] |
2014 | Ciência e Cultura Vol. 66, pp. 34-40 |
article | |
BibTeX:
@article{piedade_organismos_2014, author = {Piedade, VMF; Lopes, A; Henrique, HSS; Fé, LML; Wittmann, F., MTF; Almeida-Val}, title = {Organismos aquáticos e de áreas úmidas em uma Amazônia em transição}, journal = {Ciência e Cultura}, year = {2014}, volume = {66}, pages = {34--40} } |
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Piccolo, M.C., Neill, C., Cerri, C.C. and Melillo, J.M. | Fluxes of nitrogen following clearing of Brazilian Amazonian tropical forest for pasture [BibTeX] |
2004 | Controlling Nitrogen Flows and Losses, pp. 65-66 | incollection | URL |
BibTeX:
@incollection{hatch_fluxes_2004, author = {Piccolo, M. C. and Neill, C. and Cerri, C. C. and Melillo, J. M.}, title = {Fluxes of nitrogen following clearing of Brazilian Amazonian tropical forest for pasture}, booktitle = {Controlling Nitrogen Flows and Losses}, year = {2004}, pages = {65--66}, url = {://WOS:000226860800006} } |
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Phillips, O.L., Vasquez Martinez, R., Nunez Vargas, P., Lorenzo Monteagudo, A., Chuspe Zans, M.E., Galiano Sanchez, W., Pena Cruz, A., Timana, M., Yli-Halla, M. and Rose, S. | Efficient plot-based floristic assessment of tropical forests | 2003 | Journal of Tropical Ecology Vol. 19, pp. 629-645 |
article | DOI URL |
Abstract: The tropical flora remains chronically understudied and the lack of floristic understanding hampers ecological research and its application for large-scale conservation planning. Given scarce resources and the scale of the challenge there is a need to maximize the efficiency of both sampling strategies and sampling units, yet there is little information on the relative efficiency of different approaches to floristic assessment in tropical forests. This paper is the first attempt to address this gap. We repeatedly sampled forests in two regions of Amazonia using the two most widely used plot-based protocols of floristic sampling, and compared their performance in terms of the quantity of floristic knowledge and ecological insight gained scaled to the field effort required. Specifically, the methods are assessed first in terms of the number of person-days required to complete each sample ('effort'), secondly by the total gain in the quantity of floristic information that each unit of effort provides ('crude inventory efficiency'), and thirdly in terms of the floristic information gained as a proportion of the target species pool ('proportional inventory efficiency'). Finally, we compare the methods in terms of their efficiency in identifying different ecological patterns within the data ('ecological efficiency') while controlling for effort. There are large and consistent differences in the performance of the two methods. The disparity is maintained even after accounting for regional and site-level variation in forest species richness, tree density and the number of field assistants. We interpret our results in the context of selecting the appropriate method for particular research purposes. | |||||
BibTeX:
@article{phillips_efficient_2003, author = {Phillips, O. L. and Vasquez Martinez, R. and Nunez Vargas, P. and Lorenzo Monteagudo, A. and Chuspe Zans, M. E. and Galiano Sanchez, W. and Pena Cruz, A. and Timana, M. and Yli-Halla, M. and Rose, S.}, title = {Efficient plot-based floristic assessment of tropical forests}, journal = {Journal of Tropical Ecology}, year = {2003}, volume = {19}, pages = {629--645}, url = {://WOS:000186710800003}, doi = {https://doi.org/10.1017/s026467403006035} } |
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Phillips, O.L., Vargas, P.N., Monteagudo, A.L., Cruz, A.P., Zans, M.E.C., Sanchez, W.G., Yli-Halla, M. and Rose, S. | Habitat association among Amazonian tree species: a landscape-scale approach | 2003 | Journal of Ecology Vol. 91(5), pp. 757-775 |
article | DOI URL |
Abstract: 1 Unravelling which factors affect where tropical trees grow is an important goal for ecologists and conservationists. At the landscape scale, debate is mostly focused on the degree to which the distributions of tree species are determined by soil conditions or by neutral, distance-dependent processes. Problems with spatial autocorrelation, sparse soil sampling, inclusion of species-poor sites with extreme edaphic conditions, and the difficulty of obtaining sufficient sample sizes have all complicated assessments for high diversity tropical forests. 2 We evaluated the extent and pervasiveness of habitat association of trees within a 10 000 km 2 species-rich lowland landscape of uniform climate in south-west Amazonia. Forests growing on two non-flooded landscape units were inventoried using 88 floristic plots and detailed soil analyses, sampling up to 849 tree species. We applied single-species and community-level analytical techniques (frequency-distributions of presence records, association analysis, indicator species analysis, ordination, Mantel correlations, and multiple regression of distance matrices) to quantify soil/floristic relationships while controlling for spatial autocorrelation. 3 Obligate habitat-restriction is very rare: among 230 tree species recorded in greater than or equal to 10 localities only five (2.2%) were always restricted to one landscape unit or the other. 4 However, many species show a significant tendency to habitat association. For example, using Monte Carlo randomization tests, of the 34 most dominant species across the landscape the distributions of 26 (76.5%) are significantly related to habitat. We applied density-independent and frequency-independent estimates of habitat association and found that rarer species tend to score higher, suggesting that our full community estimates of habitat association are still underestimated due to the inadequate sampling of rarer species. 5 Community-level floristic variation across the whole landscape is related to the variation in 14 of 16 measured soil variables, and to the geographical distances between samples. 6 Multiple regression of distance matrices shows that 10% of the floristic variation can be attributed to spatial autocorrelation, but even after accounting for this at least 40% is attributable to measured environmental variation. 7 Our results suggest that substrate-mediated local processes play a much more important role than distance-dependent processes in structuring forest composition in Amazonian landscapes. | |||||
BibTeX:
@article{phillips_habitat_2003, author = {Phillips, O. L. and Vargas, P. N. and Monteagudo, A. L. and Cruz, A. P. and Zans, M. E. C. and Sanchez, W. G. and Yli-Halla, M. and Rose, S.}, title = {Habitat association among Amazonian tree species: a landscape-scale approach}, journal = {Journal of Ecology}, year = {2003}, volume = {91}, number = {5}, pages = {757--775}, url = {://WOS:000185446200005}, doi = {https://doi.org/10.1046/j.1365-2745.2003.00815.x} } |
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Phillips, O.L., van der Heijden, G., Lewis, S.L., Lopez-Gonzalez, G., Aragao, L.E.O.C., Lloyd, J., Malhi, Y., Monteagudo, A., Almeida, S., Alvarez Davila, E., Amaral, I., Andelman, S., Andrade, A., Arroyo, L., Aymard, G., Baker, T.R., Blanc, L., Bonal, D., Alves de Oliveira, A.C., Chao, K.-J., Davila Cardozo, N., da Costa, L., Feldpausch, T.R., Fisher, J.B., Fyllas, N.M., Freitas, M.A., Galbraith, D., Gloor, E., Higuchi, N., Honorio, E., Jimenez, E., Keeling, H., Killeen, T.J., Lovett, J.C., Meir, P., Mendoza, C., Morel, A., Nunez Vargas, P., Patino, S., Peh, K.S.H., Pena Cruz, A., Prieto, A., Quesada, C.A., Ramirez, F., Ramirez, H., Rudas, A., Salamao, R., Schwarz, M., Silva, J., Silveira, M., Slik, J.W.F., Sonke, B., Thomas, A.S., Stropp, J., Taplin, J.R.D., Vasquez, R. and Vilanova, E. | Drought-mortality relationships for tropical forests | 2010 | New Phytologist Vol. 187(3), pp. 631-646 |
article | DOI URL |
Abstract: The rich ecology of tropical forests is intimately tied to their moisture status. Multi-site syntheses can provide a macro-scale view of these linkages and their susceptibility to changing climates. Here, we report pan-tropical and regional-scale analyses of tree vulnerability to drought. We assembled available data on tropical forest tree stem mortality before, during, and after recent drought events, from 119 monitoring plots in 10 countries concentrated in Amazonia and Borneo. In most sites, larger trees are disproportionately at risk. At least within Amazonia, low wood density trees are also at greater risk of drought-associated mortality, independent of size. For comparable drought intensities, trees in Borneo are more vulnerable than trees in the Amazon. There is some evidence for lagged impacts of drought, with mortality rates remaining elevated 2 yr after the meteorological event is over. These findings indicate that repeated droughts would shift the functional composition of tropical forests toward smaller, denser-wooded trees. At very high drought intensities, the linear relationship between tree mortality and moisture stress apparently breaks down, suggesting the existence of moisture stress thresholds beyond which some tropical forests would suffer catastrophic tree mortality. | |||||
BibTeX:
@article{phillips_drought-mortality_2010, author = {Phillips, Oliver L. and van der Heijden, Geertje and Lewis, Simon L. and Lopez-Gonzalez, Gabriela and Aragao, Luiz E. O. C. and Lloyd, Jon and Malhi, Yadvinder and Monteagudo, Abel and Almeida, Samuel and Alvarez Davila, Esteban and Amaral, Ieda and Andelman, Sandy and Andrade, Ana and Arroyo, Luzmila and Aymard, Gerardo and Baker, Tim R. and Blanc, Lilian and Bonal, Damien and Alves de Oliveira, Atila Cristina and Chao, Kuo-Jung and Davila Cardozo, Nallaret and da Costa, Lola and Feldpausch, Ted R. and Fisher, Joshua B. and Fyllas, Nikolaos M. and Freitas, Maria Aparecida and Galbraith, David and Gloor, Emanuel and Higuchi, Niro and Honorio, Euridice and Jimenez, Eliana and Keeling, Helen and Killeen, Tim J. and Lovett, Jon C. and Meir, Patrick and Mendoza, Casimiro and Morel, Alexandra and Nunez Vargas, Percy and Patino, Sandra and Peh, Kelvin S. H. and Pena Cruz, Antonio and Prieto, Adriana and Quesada, Carlos A. and Ramirez, Fredy and Ramirez, Hirma and Rudas, Agustin and Salamao, Rafael and Schwarz, Michael and Silva, Javier and Silveira, Marcos and Slik, J. W. Ferry and Sonke, Bonaventure and Thomas, Anne Sota and Stropp, Juliana and Taplin, James R. D. and Vasquez, Rodolfo and Vilanova, Emilio}, title = {Drought-mortality relationships for tropical forests}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {631--646}, note = {Edition: 2010/07/28}, url = {://WOS:000280122500028}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03359.x} } |
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Phillips, O.L., Martinez, R.V., Mendoza, A.M., Baker, T.R. and Vargas, P.N. | Large lianas as hyperdynamic elements of the tropical forest canopy | 2005 | Ecology Vol. 86(5), pp. 1250-1258 |
article | DOI URL |
Abstract: Lianas (woody vines) are an important component of lowland tropical forests. We report large liana and tree inventory and dynamics data from Amazonia over periods of up to 24 years, making this the longest geographically extensive study of liana ecology to date. We use these results to address basic questions about the ecology of large lianas in mature forests and their interactions with trees. In one intensively studied site we find that large lianas (&GE; 10 cm diameter) represent < 5% of liana stems, but 80% of biomass of well-lit upper canopy lianas. Across sites, large lianas and large trees are both most successful in terms of structural importance in richer soil forests, but large liana success may be controlled more by the availability of large tree supports rather than directly by soil conditions. Long-term annual turnover rates of large lianas are 5-8%, three times those of trees. Lianas are implicated in large tree mortality: liana-infested large trees are three times more likely to die than liana-free large trees, and large lianas are involved in the death of at least 30% of tree basal area. Thus large lianas are a much more dynamic component of Amazon forests than are canopy trees, and they play a much more significant functional role than their structural contribution suggests. | |||||
BibTeX:
@article{phillips_large_2005, author = {Phillips, O. L. and Martinez, R. V. and Mendoza, A. M. and Baker, T. R. and Vargas, P. N.}, title = {Large lianas as hyperdynamic elements of the tropical forest canopy}, journal = {Ecology}, year = {2005}, volume = {86}, number = {5}, pages = {1250--1258}, url = {://WOS:000228960000020}, doi = {https://doi.org/10.1890/04-1446} } |
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Phillips, O.L., Martinez, R.V., Arroyo, L., Baker, T.R., Killeen, T., Lewis, S.L., Malhi, Y., Mendoza, A.M., Neill, D., Vargas, P.N., Alexiades, M., Ceron, C., Di Fiore, A., Erwin, T., Jardim, A., Palacios, W., Saldias, M. and Vinceti, B. | Increasing dominance of large lianas in Amazonian forests | 2002 | Nature Vol. 418(6899), pp. 770-774 |
article | DOI URL |
Abstract: Ecological orthodoxy suggests that old-growth forests should be close to dynamic equilibrium, but this view has been challenged by recent findings that neotropical forests are accumulating carbon(1,2) and biomass(3,4), possibly in response to the increasing atmospheric concentrations of carbon dioxide(5,6). However, it is unclear whether the recent increase in tree biomass has been accompanied by a shift in community composition. Such changes could reduce or enhance the carbon storage potential of old-growth forests in the long term. Here we show that non-fragmented Amazon forests are experiencing a concerted increase in the density, basal area and mean size of woody climbing plants (lianas). Over the last two decades of the twentieth century the dominance of large lianas relative to trees has increased by 1.7-4.6% a year. Lianas enhance tree mortality and suppress tree growth(7), so their rapid increase implies that the tropical terrestrial carbon sink may shut down sooner than current models suggest(8-10). Predictions of future tropical carbon fluxes will need to account for the changing composition and dynamics of supposedly undisturbed forests. | |||||
BibTeX:
@article{phillips_increasing_2002, author = {Phillips, O. L. and Martinez, R. V. and Arroyo, L. and Baker, T. R. and Killeen, T. and Lewis, S. L. and Malhi, Y. and Mendoza, A. M. and Neill, D. and Vargas, P. N. and Alexiades, M. and Ceron, C. and Di Fiore, A. and Erwin, T. and Jardim, A. and Palacios, W. and Saldias, M. and Vinceti, B.}, title = {Increasing dominance of large lianas in Amazonian forests}, journal = {Nature}, year = {2002}, volume = {418}, number = {6899}, pages = {770--774}, note = {Edition: 2002/08/16}, url = {://WOS:000177428000037}, doi = {https://doi.org/10.1038/nature00926} } |
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Phillips, O.L., Malhi, Y., Vinceti, B., Baker, T., Lewis, S.L., Higuchi, N., Laurance, W.F., Vargas, P.N., Martinez, R.V., Laurance, S., Ferreira, L.V., Stern, M., Brown, S. and Grace, J. | Changes in growth of tropical forests: Evaluating potential biases | 2002 | Ecological Applications Vol. 12(2), pp. 576-587 |
article | DOI URL |
Abstract: Over the past century almost every ecosystem on Earth has come under the influence of changes in atmospheric composition and climate caused by human activity, Tropical forests are among the most productive and extensive ecosystems, and it has been hypothesized that both the dynamics and biomass of apparently undisturbed, old-growth tropical forests have been changing in response to atmospheric changes. Long-term forest sample plots are a critical tool in detecting and monitoring such changes, and our recent analysis of pan-tropical-forest plot data has suggested that the biomass of tropical forests has been increaing. providing a modest negative feedback on the rate of accumulation of atmospheric CO2. However it has been argued that some of these old forest plot data sets have significant problems in interpretation because of the use of nonstandardized methodologies. In this paper we examine the extent to which potential field methodological errors may bias estimates of total biomass change by detailed examination of tree-by-tree records from up to 120 Neotropical plots to test prediction,; from theory. Potential positive biases on measurements of biomass change include a bias in site selection, tree deformities introduced by the measurement process. poor methodologies to deal with tree deformities or buttresses, and nonrecording of negative growth increments. We show that, while it is important to improve and standardize methodologies in current and future forest-plot work, any systematic errors introduced by currently identified biases in past studies are small and calculable. We conclude that most tropical-forest plot data are of useful quality, and that the evidence does still weigh conclusively in favor of a recent increase of biomass in old-growth tropical forests. | |||||
BibTeX:
@article{phillips_changes_2002, author = {Phillips, O. L. and Malhi, Y. and Vinceti, B. and Baker, T. and Lewis, S. L. and Higuchi, N. and Laurance, W. F. and Vargas, P. N. and Martinez, R. V. and Laurance, S. and Ferreira, L. V. and Stern, M. and Brown, S. and Grace, J.}, title = {Changes in growth of tropical forests: Evaluating potential biases}, journal = {Ecological Applications}, year = {2002}, volume = {12}, number = {2}, pages = {576--587}, url = {://WOS:000174457800022 http://www.esajournals.org/doi/pdf/10.1890/1051-0761%282002%29012%5B0576%3ACIGOTF%5D2.0.CO%3B2}, doi = {https://doi.org/10.2307/3060964} } |
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Phillips, O.L., Malhi, Y., Higuchi, N., Laurance, W.F., Nunez, P.V., Vasquez, R.M., Laurance, S.G., Ferreira, L.V., Stern, M., Brown, S. and Grace, J. | Changes in the carbon balance of tropical forests: Evidence from long-term plots | 1998 | Science Vol. 282(5388), pp. 439-442 |
article | DOI URL |
Abstract: The role of the world's forests as a "sink" for atmospheric carbon dioxide is the subject of active debate. Long-term monitoring of plots in mature humid tropical forests concentrated in South America revealed that biomass gain by tree growth exceeded Losses from tree death in 38 of 50 Neotropical sites. These forest plots have accumulated 0.71 ton, plus or minus 0.34 ton, of carbon per hectare per year in recent decades. The data suggest that Neotropical forests may be a significant carbon sink, reducing the rate of increase in atmospheric carbon dioxide. | |||||
BibTeX:
@article{phillips_changes_1998, author = {Phillips, O. L. and Malhi, Y. and Higuchi, N. and Laurance, W. F. and Nunez, P. V. and Vasquez, R. M. and Laurance, S. G. and Ferreira, L. V. and Stern, M. and Brown, S. and Grace, J.}, title = {Changes in the carbon balance of tropical forests: Evidence from long-term plots}, journal = {Science}, year = {1998}, volume = {282}, number = {5388}, pages = {439--442}, note = {Edition: 1998/10/17}, url = {://WOS:000076479600043 http://www.sciencemag.org/content/282/5388/439}, doi = {https://doi.org/10.1126/science.282.5388.439} } |
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Phillips, O.L., Lewis, S.L., Higuchi, N. and Baker, T. | Recent Changes in Amazon Forest Biomass and Dynamics [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 191-224 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_recent_2016, author = {Phillips, Oliver L. and Lewis, Simon L. and Higuchi, Niro and Baker, Tim}, title = {Recent Changes in Amazon Forest Biomass and Dynamics}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {191--224}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Phillips, O.L., Lewis, S.L., Baker, T.R., Chao, K.-J. and Higuchi, N. | The changing Amazon forest | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1819-1827 |
article | DOI URL |
Abstract: Long-term monitoring of distributed, multiple plots is the key to quantify macroecological patterns and changes. Here we examine the evidence for concerted changes in the structure, dynamics and composition of old-growth Amazonian forests in the late twentieth century. In the 1980s and 1990s, mature forests gained biomass and underwent accelerated growth and dynamics, all consistent with a widespread, long-acting stimulation of growth. Because growth on average exceeded mortality, intact Amazonian forests have been a carbon sink. In the late twentieth century, biomass of trees of more than 10 cm diameter increased by 0.62+/-0.23 t C ha(-1) yr(-1) averaged across the basin. This implies a carbon sink in Neotropical old-growth forest of at least 0.49+/-0.18 Pg C yr(-1). If other biomass and necromass components are also increased proportionally, then the old-growth forest sink here has been 0.79+/-0.29 Pg C yr(-1), even before allowing for any gains in soil carbon stocks. This is approximately equal to the carbon emissions to the atmosphere by Amazon deforestation. There is also evidence for recent changes in Amazon biodiversity. In the future, the growth response of remaining old-growth mature Amazon forests will saturate, and these ecosystems may switch from sink to source driven by higher respiration (temperature), higher mortality (as outputs equilibrate to the growth inputs and periodic drought) or compositional change (disturbances). Any switch from carbon sink to source would have profound implications for global climate, biodiversity and human welfare, while the documented acceleration of tree growth and mortality may already be affecting the interactions among millions of species. | |||||
BibTeX:
@article{phillips_changing_2008, author = {Phillips, Oliver L. and Lewis, Simon L. and Baker, Timothy R. and Chao, Kuo-Jung and Higuchi, Niro}, title = {The changing Amazon forest}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1819--1827}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500014 http://rstb.royalsocietypublishing.org/content/363/1498/1819.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0033} } |
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Phillips, O.L., Higuchi, N., Vieira, S., Baker, T.R., Chao, K.-J. and Lewis, S.L. | Changes in Amazonian Forest Biomass, Dynamics, and Composition, 1980-2002 [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 373-388 |
incollection | |
BibTeX:
@incollection{m_keller_changes_2009, author = {Phillips, Oliver L. and Higuchi, Niro and Vieira, Simone and Baker, Timothy R. and Chao, Kuo-Jung and Lewis, Simon L.}, title = {Changes in Amazonian Forest Biomass, Dynamics, and Composition, 1980-2002}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {373--388} } |
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Phillips, O.L., Brienen, R.J.W. and collaboration , t.R. | Carbon uptake by mature Amazon forests has mitigated Amazon nations’ carbon emissions [BibTeX] |
2017 | Carbon Balance and Management Vol. 12 |
article | DOI |
BibTeX:
@article{phillips_carbon_2017, author = {Phillips, Oliver L. and Brienen, Roel J. W. and collaboration, the RAINFOR}, title = {Carbon uptake by mature Amazon forests has mitigated Amazon nations’ carbon emissions}, journal = {Carbon Balance and Management}, year = {2017}, volume = {12}, doi = {https://doi.org/10.1186/s13021-016-0069-2} } |
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Phillips, O.L., Baker, T.R., Arroyo, L., Higuchi, N., Killeen, T.J., Laurance, W.F., Lewis, S.L., Lloyd, J., Malhi, Y., Monteagudo, A., Neill, D.A., Vargas, P.N., Silva, J.N.M., Terborgh, J., Martinez, R.V., Alexiades, M., Almeida, S., Brown, S., Chave, J., Comiskey, J.A., Czimczik, C.I., Di Fiore, A., Erwin, T., Kuebler, C., Laurance, S.G., Nascimento, H.E.M., Olivier, J., Palacios, W., Patino, S., Pitman, N.C.A., Quesada, C.A., Salidas, M., Lezama, A.T. and Vinceti, B. | Pattern and process in Amazon tree turnover, 1976-2001 | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 381-407 |
article | DOI URL |
Abstract: Previous work has shown that tree turnover, tree biomass and large liana densities have increased in mature tropical forest plots in the late twentieth century. These results point to a concerted shift in forest ecological processes that may already be having significant impacts on terrestrial carbon stocks, fluxes and biodiversity. However, the findings have proved controversial, partly because a rather limited number of permanent plots have been monitored for rather short periods. The aim of this paper is to characterize regional-scale patterns of 'tree turnover' (the rate with which trees die and recruit into a population) by using improved datasets now available for Amazonia that span the past 25 years. Specifically, we assess whether concerted changes in turnover are occurring, and if so whether they are general throughout the Amazon or restricted to one region or environmental zone. In addition, we ask whether they are driven by changes in recruitment, mortality or both. We find that: (i) trees 10 cm or more in diameter recruit and die twice as fast on the richer soils of southern and western Amazonia than on the poorer soils of eastern and central Amazonia; (ii) turnover rates have increased throughout Amazonia over the past two decades; (iii) mortality and recruitment rates have both increased significantly in every region and environmental zone, with the exception of mortality in eastern Amazonia; (iv) recruitment rates have consistently exceeded mortality rates; (v) absolute increases in recruitment and mortality rates are greatest in western Amazonian sites; and (vi) mortality appears to be lagging recruitment at regional scales. These spatial patterns and temporal trends are not caused by obvious artefacts in the data or the analyses. The trends cannot be directly driven by a mortality driver (such as increased drought or fragmentation-related death) because the biomass in these forests has simultaneously increased. Our findings therefore indicate that long-acting and widespread environmental changes are stimulating the growth and productivity of Amazon forests. | |||||
BibTeX:
@article{phillips_pattern_2004, author = {Phillips, O. L. and Baker, T. R. and Arroyo, L. and Higuchi, N. and Killeen, T. J. and Laurance, W. F. and Lewis, S. L. and Lloyd, J. and Malhi, Y. and Monteagudo, A. and Neill, D. A. and Vargas, P. N. and Silva, J. N. M. and Terborgh, J. and Martinez, R. V. and Alexiades, M. and Almeida, S. and Brown, S. and Chave, J. and Comiskey, J. A. and Czimczik, C. I. and Di Fiore, A. and Erwin, T. and Kuebler, C. and Laurance, S. G. and Nascimento, H. E. M. and Olivier, J. and Palacios, W. and Patino, S. and Pitman, N. C. A. and Quesada, C. A. and Salidas, M. and Lezama, A. T. and Vinceti, B.}, title = {Pattern and process in Amazon tree turnover, 1976-2001}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {381--407}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100007}, doi = {https://doi.org/10.1098/rstb.2003.1438} } |
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Phillips, O.L., Aragao, L.E.O.C., Lewis, S.L., Fisher, J.B., Lloyd, J., Lopez-Gonzalez, G., Malhi, Y., Monteagudo, A., Peacock, J., Quesada, C.A., van der Heijden, G., Almeida, S., Amaral, I., Arroyo, L., Aymard, G., Baker, T.R., Banki, O., Blanc, L., Bonal, D., Brando, P., Chave, J., Alves de Oliveira, A.C., Cardozo, N.D., Czimczik, C.I., Feldpausch, T.R., Freitas, M.A., Gloor, E., Higuchi, N., Jimenez, E., Lloyd, G., Meir, P., Mendoza, C., Morel, A., Neill, D.A., Nepstad, D., Patino, S., Cristina Penuela, M., Prieto, A., Ramirez, F., Schwarz, M., Silva, J., Silveira, M., Thomas, A.S., ter Steege, H., Stropp, J., Vasquez, R., Zelazowski, P., Alvarez Davila, E., Andelman, S., Andrade, A., Chao, K.-J., Erwin, T., Di Fiore, A., Honorio C, E., Keeling, H., Killeen, T.J., Laurance, W.F., Pena Cruz, A., Pitman, N.C.A., Nunez Vargas, P., Ramirez-Angulo, H., Rudas, A., Salamao, R., Silva, N., Terborgh, J. and Torres-Lezama, A. | Drought Sensitivity of the Amazon Rainforest | 2009 | Science Vol. 323(5919), pp. 1344-1347 |
article | DOI URL |
Abstract: Amazon forests are a key but poorly understood component of the global carbon cycle. If, as anticipated, they dry this century, they might accelerate climate change through carbon losses and changed surface energy balances. We used records from multiple long-term monitoring plots across Amazonia to assess forest responses to the intense 2005 drought, a possible analog of future events. Affected forest lost biomass, reversing a large long-term carbon sink, with the greatest impacts observed where the dry season was unusually intense. Relative to pre-2005 conditions, forest subjected to a 100-millimeter increase in water deficit lost 5.3 megagrams of aboveground biomass of carbon per hectare. The drought had a total biomass carbon impact of 1.2 to 1.6 petagrams (1.2 x 10(15) to 1.6 x 10(15) grams). Amazon forests therefore appear vulnerable to increasing moisture stress, with the potential for large carbon losses to exert feedback on climate change. | |||||
BibTeX:
@article{phillips_drought_2009, author = {Phillips, Oliver L. and Aragao, Luiz E. O. C. and Lewis, Simon L. and Fisher, Joshua B. and Lloyd, Jon and Lopez-Gonzalez, Gabriela and Malhi, Yadvinder and Monteagudo, Abel and Peacock, Julie and Quesada, Carlos A. and van der Heijden, Geertje and Almeida, Samuel and Amaral, Ieda and Arroyo, Luzmila and Aymard, Gerardo and Baker, Tim R. and Banki, Olaf and Blanc, Lilian and Bonal, Damien and Brando, Paulo and Chave, Jerome and Alves de Oliveira, Atila Cristina and Cardozo, Nallaret Davila and Czimczik, Claudia I. and Feldpausch, Ted R. and Freitas, Maria Aparecida and Gloor, Emanuel and Higuchi, Niro and Jimenez, Eliana and Lloyd, Gareth and Meir, Patrick and Mendoza, Casimiro and Morel, Alexandra and Neill, David A. and Nepstad, Daniel and Patino, Sandra and Cristina Penuela, Maria and Prieto, Adriana and Ramirez, Fredy and Schwarz, Michael and Silva, Javier and Silveira, Marcos and Thomas, Anne Sota and ter Steege, Hans and Stropp, Juliana and Vasquez, Rodolfo and Zelazowski, Przemyslaw and Alvarez Davila, Esteban and Andelman, Sandy and Andrade, Ana and Chao, Kuo-Jung and Erwin, Terry and Di Fiore, Anthony and Honorio C, Euridice and Keeling, Helen and Killeen, Tim J. and Laurance, William F. and Pena Cruz, Antonio and Pitman, Nigel C. A. and Nunez Vargas, Percy and Ramirez-Angulo, Hirma and Rudas, Agustin and Salamao, Rafael and Silva, Natalino and Terborgh, John and Torres-Lezama, Armando}, title = {Drought Sensitivity of the Amazon Rainforest}, journal = {Science}, year = {2009}, volume = {323}, number = {5919}, pages = {1344--1347}, note = {Edition: 2009/03/07}, url = {://WOS:000263876700042}, doi = {https://doi.org/10.1126/science.1164033} } |
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Phillips, O.L. | Drought, dispersal, and distribution in the inner tropics [BibTeX] |
2007 | Journal of Biogeography Vol. 34(11), pp. 1846-1847 |
article | DOI URL |
BibTeX:
@article{phillips_drought_2007, author = {Phillips, Oliver L.}, title = {Drought, dispersal, and distribution in the inner tropics}, journal = {Journal of Biogeography}, year = {2007}, volume = {34}, number = {11}, pages = {1846--1847}, url = {://WOS:000250263900002}, doi = {https://doi.org/10.1111/j.1365-2699.2007.01805.x} } |
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Pfannerstill, E.Y., Reijrink, N.G., Edtbauer, A., Ringsdorf, A., Zannoni, N., Araújo, A., Ditas, F., Holanda, B.A., Sá, M.O., Tsokankunku, A., Walter, D., Wolff, S., Lavrič, J.V., Pöhlker, C., Sörgel, M. and Williams, J. | Total OH reactivity over the Amazon rainforest: variability with temperature, wind, rain, altitude, time of day, season, and an overall budget closure [BibTeX] |
2021 | Atmos. Chem. Phys. Vol. 21(8), pp. 6231-6256 |
article | DOI URL |
BibTeX:
@article{pfannerstill_total_2021, author = {Pfannerstill, E. Y. and Reijrink, N. G. and Edtbauer, A. and Ringsdorf, A. and Zannoni, N. and Araújo, A. and Ditas, F. and Holanda, B. A. and Sá, M. O. and Tsokankunku, A. and Walter, D. and Wolff, S. and Lavrič, J. V. and Pöhlker, C. and Sörgel, M. and Williams, J.}, title = {Total OH reactivity over the Amazon rainforest: variability with temperature, wind, rain, altitude, time of day, season, and an overall budget closure}, journal = {Atmos. Chem. Phys.}, year = {2021}, volume = {21}, number = {8}, pages = {6231--6256}, url = {https://acp.copernicus.org/articles/21/6231/2021/}, doi = {https://doi.org/10.5194/acp-21-6231-2021} } |
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Pfannerstill, E.Y., Nölscher, A.C., Yáñez-Serrano, A.M., Bourtsoukidis, E., Keßel, S., Janssen, R.H.H., Tsokankunku, A., Wolff, S., Sörgel, M., Sá, M.O., Araújo, A., Walter, D., Lavrič, J., Dias-Júnior, C.Q., Kesselmeier, J. and Williams, J. | Corrigendum: Total OH Reactivity Changes Over the Amazon Rainforest During an El Niño Event [BibTeX] |
2022 | Frontiers in Forests and Global Change Vol. 5 |
article | URL |
BibTeX:
@article{pfannerstill_corrigendum_2022, author = {Pfannerstill, Eva Y. and Nölscher, Anke C. and Yáñez-Serrano, Ana M. and Bourtsoukidis, Efstratios and Keßel, Stephan and Janssen, Ruud H. H. and Tsokankunku, Anywhere and Wolff, Stefan and Sörgel, Matthias and Sá, Marta O. and Araújo, Alessandro and Walter, David and Lavrič, Jošt and Dias-Júnior, Cléo Q. and Kesselmeier, Jürgen and Williams, Jonathan}, title = {Corrigendum: Total OH Reactivity Changes Over the Amazon Rainforest During an El Niño Event}, journal = {Frontiers in Forests and Global Change}, year = {2022}, volume = {5}, url = {https://www.frontiersin.org/articles/10.3389/ffgc.2022.952123} } |
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Pfannerstill, E.Y., Nölscher, A.C., Yáñez-Serrano, A.M., Bourtsoukidis, E., Keßel, S., Janssen, R.H.H., Tsokankunku, A., Wolff, S., Sörgel, M., Sá, M.O., Araújo, A., Walter, D., Lavrič, J., Dias-Júnior, C.Q., Kesselmeier, J. and Williams, J. | Total OH Reactivity Changes Over the Amazon Rainforest During an El Niño Event | 2018 | Frontiers in Forests and Global Change Vol. 1 |
article | DOI URL |
Abstract: The 2015/16 El Niño event caused unprecedented drought and warming in the Amazon basin. How tropical forests react to such extreme events in terms of volatile organic compound (VOC) emissions is of interest as the frequency of these events is predicted to increase through climate change. The diverse VOCs emitted can be significant for plants' carbon budgets, influence ozone and particle production, and through their reactivity impact OH concentrations. Total OH reactivity is a directly measureable quantity that gives the reaction frequency of OH radicals with all reactive species in the atmosphere in s^−1. Here we present a comparison of the OH reactivity diel cycle from November 2015, i.e., extreme drought and elevated temperatures associated with strong El Niño conditions, with November 2012, a “normal” El Niño Southern Oscillation (ENSO)-neutral period. Interestingly, the diel maximum of OH reactivity during the El Niño event occurred at sunset instead of, under normal conditions, early afternoon. The absolute total diel OH reactivity, however, did not change significantly. Daytime OH reactivity averages were 24.3 ± 14.5 s^−1 in 2012 and 24.6 ± 11.9 s^−1 in 2015, respectively. Our findings suggest that a combination of stronger turbulent transport above the canopy with stress-related monoterpene and, possibly, other biogenic volatile organic compound (BVOC) emissions were responsible for the increased reactivity at sunset. | |||||
BibTeX:
@article{pfannerstill_total_2018, author = {Pfannerstill, Eva Y. and Nölscher, Anke C. and Yáñez-Serrano, Ana M. and Bourtsoukidis, Efstratios and Keßel, Stephan and Janssen, Ruud H. H. and Tsokankunku, Anywhere and Wolff, Stefan and Sörgel, Matthias and Sá, Marta O. and Araújo, Alessandro and Walter, David and Lavrič, Jošt and Dias-Júnior, Cléo Q. and Kesselmeier, Jürgen and Williams, Jonathan}, title = {Total OH Reactivity Changes Over the Amazon Rainforest During an El Niño Event}, journal = {Frontiers in Forests and Global Change}, year = {2018}, volume = {1}, url = {https://www.frontiersin.org/articles/10.3389/ffgc.2018.00012}, doi = {https://doi.org/10.3389/ffgc.2018.00012} } |
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Pfaff, A. and Walker, R. | Regional interdependence and forest "transitions": Substitute deforestation limits the relevance of local reversals | 2010 | Land Use Policy Vol. 27(2), pp. 119-129 |
article | DOI URL |
Abstract: Using case studies and concepts we suggest that constraints upon aggregate or global forest transition are significantly more severe than those upon local forest reversals. The basic reason is that one region's reversal can be facilitated by other regions that supply resources and goods, reducing the demands upon the region where forests rise. Many past forest reversals involve such interdependence. For 'facilitating regions' also to rise in forest requires other changes, since they will not be receiving such help. We start by discussing forest-transitions analysis within the context of Environmental Kuznets Curves (EKCs), for a useful typology of possible shifts underlying transitions. We then consider the historical Northeast US where a regional reversal was dramatic and impressive. Yet this depended upon agricultural price shocks, due to the Midwest US supplying food, and also upon the availability of timber from other US regions. Next we consider deforestation in Amazonia, whose history (like the Northeast US) suggests a potential local role for urbanization, i.e. spatial concentration of population. Yet inter-regional issues again are crucial. For cattle and soy, expansion of global demands may give to Amazonia a role more like the Midwest than the Northeast US. In addition, across-region interdependencies will help determine where reversal and facilitation occur. Finally we discuss the constraints upon very broad forest transition. (C) 2009 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{pfaff_regional_2010, author = {Pfaff, Alexander and Walker, Robert}, title = {Regional interdependence and forest "transitions": Substitute deforestation limits the relevance of local reversals}, journal = {Land Use Policy}, year = {2010}, volume = {27}, number = {2}, pages = {119--129}, url = {://WOS:000273110500004}, doi = {https://doi.org/10.1016/j.landusepol.2009.07.010} } |
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Pfaff, A., Robalino, J., Walker, R., Aldrich, S., Caldas, M., Reis, E.J., Perz, S., Bohrer, C., Arima, E., Laurance, W. and Kirby, K.R. | Roads and deforestation in the Brazilian Amazon | 2007 | Journal of Regional Science Vol. 47(1), pp. 109-123 |
article | DOI URL |
Abstract: Understanding the impact of road investments on deforestation is part of a complete evaluation of the expansion of infrastructure for development. We find evidence of spatial spillovers from roads in the Brazilian Amazon: deforestation rises in the census tracts that lack roads but are in the same county as and within 100 km of a tract with a new paved or unpaved road. At greater distances from the new roads the evidence is mixed, including negative coefficients of inconsistent significance between 100 and 300 km, and if anything, higher neighbor deforestation at distances over 300 km. | |||||
BibTeX:
@article{pfaff_roads_2007, author = {Pfaff, A. and Robalino, J. and Walker, R. and Aldrich, S.P. and Caldas, M. and Reis, E. J. and Perz, S. and Bohrer, C. and Arima, E. and Laurance, W. and Kirby, K. R.}, title = {Roads and deforestation in the Brazilian Amazon}, journal = {Journal of Regional Science}, year = {2007}, volume = {47}, number = {1}, pages = {109--123}, url = {://WOS:000243870500006}, doi = {https://doi.org/10.1111/j.1467-9787.2007.00502.x} } |
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Pfaff, A., Barbieri, A., Ludwigs, T., Merry, F., Perz, S. and Reis, E. | Road Impacts in Brazilian Amazonia [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 101-116 |
incollection | |
BibTeX:
@incollection{m_keller_road_2009, author = {Pfaff, Alexander and Barbieri, Alisson and Ludwigs, Thomas and Merry, Frank and Perz, Stephen and Reis, Eustáquio}, title = {Road Impacts in Brazilian Amazonia}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {101--116} } |
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Peterson, C.J., Ribeiro, G.H.P.d.M., Negrón-Juárez, R., Marra, D.M., Chambers, J.Q., Higuchi, N., Lima, A. and Cannon, J.B. | Critical wind speeds suggest wind could be an important disturbance agent in Amazonian forests | 2019 | Forestry: An International Journal of Forest Research Vol. 92(4), pp. 444-459 |
article | DOI URL |
Abstract: Recent research in the central Amazon suggests that wind is a major agent of disturbance, however, a mechanistic understanding of how wind may lead to tree mortality in Amazonian forests remains unclear. Here we estimated wind speeds necessary to topple central Amazon trees by linking both static and dynamic versions of two wind speed estimation methods (four methods total) to field data on tree failure derived from a static winching study. Static versions of these methods assumed invariant wind characteristics as more trees failed, while dynamic versions updated tree spacing, leaf area index and wind profiles progressively after each tree failure. First, we used a profile method which estimates wind force on individual trees by segments. We calculated drag on each segment and converted drag into basal turning moment, and compared the summed turning moments to the critical turning moment measured in the winching study. Estimated critical wind speeds from the static profile method varied greatly, from 10.75 m s−1 to >120.0 m s−1 with a mean of 45.70 m s−1. Critical wind speeds estimated with static approaches decreased with tree size but were not significantly different between two focal genera. Primary drivers of variation in critical wind speed were tree height and crown size. Second, we used the turning moment coefficient method of Hale, S.E., Gardiner, B., Peace, A., Nicoll, B., Taylor, P. and Pizzirani, S. 2015 Comparison and validation of three versions of a forest wind risk model. Environ. Model. Softw.68, 27–41. doi:10.1016/j.envsoft.2015.01.016.; the static version of this method yielded less-variable estimates, ranging from 18.98 to 52.01 m s−1, with a mean of 30.88 m s−1. Notably, the two static methods for estimating critical wind speeds differed in the trees they identified as having the highest and lowest critical wind speeds. Dynamic variants of the above two methods produced greatly reduced ranges in CWS estimates for our study trees, because after the early tree failures, remaining trees were subject to greater wind penetration into the stand and thus greater loading for a given above-canopy wind speed. CWS estimated with dynamic approaches differed significantly between the focal taxa. Nevertheless, both estimates suggest that wind speeds commonly observed during Amazon storms are sufficient to produce widespread tree damage and mortality. | |||||
BibTeX:
@article{peterson_critical_2019, author = {Peterson, Chris J and Ribeiro, Gabriel Henrique Pires de Mello and Negrón-Juárez, Robinson and Marra, Daniel Magnabosco and Chambers, Jeffrey Q and Higuchi, Niro and Lima, Adriano and Cannon, Jeffery B}, title = {Critical wind speeds suggest wind could be an important disturbance agent in Amazonian forests}, journal = {Forestry: An International Journal of Forest Research}, year = {2019}, volume = {92}, number = {4}, pages = {444--459}, url = {https://doi.org/10.1093/forestry/cpz025}, doi = {https://doi.org/10.1093/forestry/cpz025} } |
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Petersen, W.A. and Rutledge, S.A. | Regional variability in tropical convection: Observations from TRMM | 2001 | Journal of Climate Vol. 14(17), pp. 3566-3586 |
article | DOI URL |
Abstract: Observation of the vertical profile of precipitation over the global Tropics is a key objective of the Tropical Rainfall Measuring Mission (TRMM) because this information is central to obtaining vertical profiles of latent heating. This study combines both TRMM precipitation radar (PR) and Lightning Imaging Sensor (LIS) data to examine "wet-season'' vertical structures of tropical precipitation across a broad spectrum of locations in the global Tropics. TRMM-PR reflectivity data (2A25 algorithm) were utilized to produce seasonal mean three-dimensional relative frequency histograms and precipitation ice water contents over grid boxes of approximately 5 degrees -10 degrees in latitude and longitude. The reflectivity histograms and ice water contents were then combined with LIS lightning flash densities and 2A25 mean rainfall rates to examine regional relationships between precipitation vertical structure, precipitation processes, and lightning production. Analysis of the reflectivity vertical structure histograms and lightning flash density data reveals that 1) relative to tropical continental locations, wet-season isolated tropical oceanic locations exhibit relatively little spatial (and in some instances seasonal) variability in vertical structure across the global Tropics; 2) coastal locations and areas located within 500-1000 km of a continent exhibit considerable seasonal and spatial variability in mean vertical structure, often resembling "continental'' profiles or falling intermediate to that of tropical continental and isolated oceanic regimes; and 3) interior tropical continental locations exhibit marked variability in vertical structure both spatially and seasonally, exhibiting a continuum of characteristics ranging from a near-isolated oceanic profile observed over the central Amazon and India to a more robust continental profile observed over regions such as the Congo and Florida. Examination of regional and seasonal mean conditional instability for a small but representative subset of the geographic locations suggests that tropospheric thermodynamic structure likely plays a significant role in the regional characteristics of precipitation vertical structure and associated lightning flash density. In general, the largest systematic variability in precipitation vertical structure observed between all of the locations examined occurred above the freezing level. It is important that subfreezing temperature variability in the vertical reflectivity structures was well reflected in the seasonal mean lightning flash densities and ice water contents diagnosed for each location. In turn, systematically larger rainfall rates were observed on a pixel-by-pixel basis in locations with larger precipitation ice water content and lightning flash density. These results delineate, in a regional sense, the relative importance of mixed-phase precipitation production across the global Tropics. | |||||
BibTeX:
@article{petersen_regional_2001, author = {Petersen, W. A. and Rutledge, S. A.}, title = {Regional variability in tropical convection: Observations from TRMM}, journal = {Journal of Climate}, year = {2001}, volume = {14}, number = {17}, pages = {3566--3586}, url = {://WOS:000171134200004}, doi = {https://doi.org/10.1175/1520-0442(2001)014%3C3566:rvitco%3E2.0.co;2} } |
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Petersen, W.A., Nesbitt, S.W., Blakeslee, R.J., Cifelli, R., Hein, P. and Rutledge, S.A. | TRMM observations of intraseasonal variability in convective regimes over the Amazon | 2002 | Journal of Climate Vol. 15(11), pp. 1278-1294 |
article | DOI URL |
Abstract: This study utilizes the Tropical Rainfall Measuring Mission (TRMM) satellite precipitation radar (PR), lightning imaging sensor (LIS), and passive microwave imager (TMI) data together with ground-based lightning data to investigate the vertical structure, lightning, and rainfall characteristics of Amazonian and subtropical South American convection for three separate wet seasons. These characteristics are partitioned as a function of 850-mb zonal wind direction, motivated by observations collected during the 6-week TRMM-Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA) field campaign. The TRMM-LBA field campaign observations suggest that systematic variations in Amazonian convective vertical structure, lightning, and rainfall are all linked to bimodal variations in the low-level zonal wind (e. g., easterly and westerly regimes). The more spatially and temporally comprehensive TRMM dataset used in this study extends the TRMM-LBA observations by examining regime variability in Amazonian and South American convective structure over a continental-scale domain. On a continental scale, patterns of east and west regime 850-700-mb winds combined with LIS lightning flash densities suggest the presence of synoptic-scale controls [e. g., intrusion of extratropical frontal systems and interaction with the South Atlantic Convergence Zone (SACZ)] on regional-scale variability in convective vertical structure. TRMM PR, TMI, and ground-based lightning data suggest that regional variability in wet-season convective structure is most evident over the southern Amazon, Mato Grosso, Altiplano, southern Brazil, and eastern coastal regions of central and southern South America. Convective vertical structure, convective rainfall rates, and lightning activity are all more pronounced during easterly (westerly) regimes over the southern Amazon and Mato Grosso (Altiplano, and southern Brazil). Importantly, when considered with case study results from TRMM-LBA, the systematic differences in convective structure that occur as a function of regime suggest that associated regime differences may exist in the vertical distribution of diabatic heating. Hence the discrimination of convective vertical structure "regimes'' over parts of the Amazon and vicinity based on a resolved variable such as the 850-700-mb zonal wind direction, while far from being perfect, may have important applications to the problems of cumulus parameterization, rainfall estimation, and retrievals of latent heating over the Amazon. | |||||
BibTeX:
@article{petersen_trmm_2002, author = {Petersen, W. A. and Nesbitt, S. W. and Blakeslee, R. J. and Cifelli, R. and Hein, P. and Rutledge, S. A.}, title = {TRMM observations of intraseasonal variability in convective regimes over the Amazon}, journal = {Journal of Climate}, year = {2002}, volume = {15}, number = {11}, pages = {1278--1294}, url = {://WOS:000175349600003}, doi = {https://doi.org/10.1175/1520-0442(2002)015%3C1278:tooivi%3E2.0.co;2} } |
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Perz, S.G., Walker, R.T. and Caldas, M.M. | Beyond population and environment: Household demographic life cycles and land use allocation among small farms in the Amazon | 2006 | Human Ecology Vol. 34(6), pp. 829-849 |
article | DOI URL |
Abstract: Most research featuring demographic factors in environmental change has focused on processes operating at the level of national or global populations. This paper focuses on household-level demographic life cycles among colonists in the Amazon, and evaluates the impacts on land use allocation. The analysis goes beyond prior research by including a broader suite of demographic variables, and by simultaneously assessing their impacts on multiple land uses with different economic and ecological implications. We estimate a system of structural equations that accounts for endogeneity among land uses, and the findings indicate stronger demographic effects than previous work. These findings bear implications for modeling land use, and the place of demography in environmental research. | |||||
BibTeX:
@article{perz_beyond_2006, author = {Perz, Stephen G. and Walker, Robert T. and Caldas, Marcellus M.}, title = {Beyond population and environment: Household demographic life cycles and land use allocation among small farms in the Amazon}, journal = {Human Ecology}, year = {2006}, volume = {34}, number = {6}, pages = {829--849}, url = {://WOS:000241522400005 http://www.springerlink.com/content/4h3410211g744wh4/fulltext.pdf}, doi = {https://doi.org/10.1007/s10745-006-9039-8} } |
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Perz, S.G. and Walker, R.T. | Household life cycles and secondary forest cover among small farm colonists in the Amazon | 2002 | World Development Vol. 30(6), pp. 1009-1027 |
article | DOI URL |
Abstract: This paper provides a household-level framework to understand the occurrence of secondary forests. We focus on the role of household life cycles as determinants of secondary vegetation on small farms in tropical Latin America. Following a review of socioeconomic research on secondary growth and a theoretical discussion of life cycle dynamics and land use, we pursue an empirical analysis of the determinants of fallows and abandoned plots among farm lots in Uruara, a colony in the Brazilian Amazon. The findings indicate strong effects of life cycle factors, and bear implications for policies aiming to foster agricultural production alongside forest conservation. (C) 2002 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{perz_household_2002, author = {Perz, S. G. and Walker, R. T.}, title = {Household life cycles and secondary forest cover among small farm colonists in the Amazon}, journal = {World Development}, year = {2002}, volume = {30}, number = {6}, pages = {1009--1027}, url = {://WOS:000176136000008}, doi = {https://doi.org/10.1016/s0305-750x(02)00024-4} } |
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Perz, S.G. and Skole, D.L. | Social determinants of secondary forests in the Brazilian Amazon | 2003 | Social Science Research Vol. 32(1), pp. 25-60 |
article | DOI URL |
Abstract: This paper presents models of secondary forests ("regrowth") in the Brazilian Amazon using social indicators as explanatory factors. We draw on a spatially explicit data set containing satellite-based estimates of secondary growth, matched to census-based social indicators for municipalities in the region. The models overcome several shortcomings in previous efforts: they use smaller units of analysis to capture local heterogeneity; they include a conceptually broad range of measures to reduce omitted variable bias; they allow for estimation of separate coefficients and error terms for three distinct subregions to observe variable effects across the region and manage heteroskedasticity; and they incorporate spatial information to account for spatial autocorrelation and obtain unbiased estimates of coefficients. The findings indicate that longstanding settlement and traditional activities have positive effects on the extent of secondary forests, but in-migration and non-traditional land use exert growing influences on forest regrowth as well, especially in frontier areas of the Amazon. (C) 2002 Elsevier Science (USA). All rights reserved. | |||||
BibTeX:
@article{perz_social_2003, author = {Perz, S. G. and Skole, D. L.}, title = {Social determinants of secondary forests in the Brazilian Amazon}, journal = {Social Science Research}, year = {2003}, volume = {32}, number = {1}, pages = {25--60}, url = {://WOS:000181505600003}, doi = {https://doi.org/10.1016/s0049-089x(02)00012-1} } |
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Perz, S.G., Overdevest, C., Caldas, M.M., Walker, R.T. and Arima, E.Y. | Unofficial road building in the Brazilian Amazon: dilemmas and models for road governance | 2007 | Environmental Conservation Vol. 34(2), pp. 112-121 |
article | DOI URL |
Abstract: Unofficial roads form dense networks in landscapes, generating a litany of negative ecological outcomes, but in frontier areas they are also instrumental in local livelihoods and community development. This trade-off poses dilemmas for the governance of unofficial roads. Unofficial road building in frontier areas of the Brazilian Amazon illustrates the challenges of 'road governance.' Both state-based and community-based governance models exhibit important liabilities for governing unofficial roads. Whereas state-based governance has experienced difficulties in adapting to specific local contexts and interacting effectively with local peoples, community-based governance has a mixed record owing to social inequalities and conflicts among local interest groups. A state-community hybrid model may offer more effiective governance of unofficial road building by combining the oversight capacity of the state with locally-grounded community management via participatory decision-making. | |||||
BibTeX:
@article{perz_unofficial_2007, author = {Perz, Stephen G. and Overdevest, Christine and Caldas, Marcellus M. and Walker, Robert T. and Arima, Eugenio Y.}, title = {Unofficial road building in the Brazilian Amazon: dilemmas and models for road governance}, journal = {Environmental Conservation}, year = {2007}, volume = {34}, number = {2}, pages = {112--121}, url = {://WOS:000249057100006}, doi = {https://doi.org/10.1017/s0376892907003827} } |
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Perz, S.G. | Are Agricultural Production and Forest Conservation Compatible? Agricultural Diversity, Agricultural Incomes and Primary Forest Cover Among Small Farm Colonists in the Amazon | 2004 | World Development Vol. 32(6), pp. 957-977 |
article | DOI URL |
Abstract: This paper presents an empirical analysis that addresses recent work seeking "win-win-win" scenarios for economic development, poverty reduction and environmental sustainability. I focus on arguments for "productive conservation" in forest frontier regions, namely raising rural incomes while conserving the forest resource base. The analysis examines the impacts of agricultural product and income diversity on agricultural incomes and primary forest cover. The findings show that net of other factors, more diversified farms have higher agricultural incomes, but not significantly less forest cover. This finding is consistent with recent work in other study sites and suggests that initiatives promoting agricultural diversity can at least partially compatibilize production and conservation. (C) 2004 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{perz_are_2004, author = {Perz, Stephen G.}, title = {Are Agricultural Production and Forest Conservation Compatible? Agricultural Diversity, Agricultural Incomes and Primary Forest Cover Among Small Farm Colonists in the Amazon}, journal = {World Development}, year = {2004}, volume = {32}, number = {6}, pages = {957--977}, url = {://WOS:000221841900005}, doi = {https://doi.org/10.1016/j.worlddev.2003.10.012} } |
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Perz, S., Messina, J.P., Reis, E., Walker, R. and Walsh, S.J. | Scenarios of Future Amazonian Landscapes: Econometric and Dynamic Simulation Models [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 83-100 |
incollection | |
BibTeX:
@incollection{m_keller_scenarios_2009, author = {Perz, S. and Messina, Joseph P. and Reis, Eustáquio and Walker, Robert and Walsh, Stephen J.}, title = {Scenarios of Future Amazonian Landscapes: Econometric and Dynamic Simulation Models}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {83--100} } |
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Perz, S., Brilhante, S., Brown, F., Caldas, M., Ikeda, S., Mendoza, E., Overdevest, C., Reis, V., Reyes, J.F., Rojas, D., Schmink, M., Souza, C. and Walker, R. | Road building, land use and climate change: prospects for environmental governance in the Amazon | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1889-1895 |
article | DOI URL |
Abstract: Some coupled land-climate models predict a dieback of Amazon forest during the twenty-first century due to climate change, but human land use in the region has already reduced the forest cover. The causation behind land use is complex, and includes economic, institutional, political and demographic factors. Pre-eminent among these factors is road building, which facilitates human access to natural resources that beget forest fragmentation. While official government road projects have received considerable attention, unofficial road building by interest groups is expanding more rapidly, especially where official roads are being paved, yielding highly fragmented forest mosaics. Effective governance of natural resources in the Amazon requires a combination of state oversight and community participation in a 'hybrid' model of governance. The MAP Initiative in the southwestern Amazon provides an example of an innovative hybrid approach to environmental governance. It embodies a polycentric structure that includes government agencies, NGOs, universities and communities in a planning process that links scientific data to public deliberations in order to mitigate the effects of new infrastructure and climate change. | |||||
BibTeX:
@article{perz_road_2008, author = {Perz, Stephen and Brilhante, Silvia and Brown, Foster and Caldas, Marcellus and Ikeda, Santos and Mendoza, Elsa and Overdevest, Christine and Reis, Vera and Reyes, Juan Fernando and Rojas, Daniel and Schmink, Marianne and Souza, Carlos and Walker, Robert}, title = {Road building, land use and climate change: prospects for environmental governance in the Amazon}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1889--1895}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500022}, doi = {https://doi.org/10.1098/rstb.2007.0017} } |
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Pérez, T., Trumbore, S.E., Tyler, S.C., Matson, P.A., Ortiz-Monasterio, I., Rahn, T. and Griffith, D.W.T. | Identifying the agricultural imprint on the global N2O budget using stable isotopes | 2001 | Journal of Geophysical Research Vol. 106(D9), pp. 9869-9878 |
article | DOI URL |
Abstract: Agricultural soils are the most important anthropogenic source of nitrous oxide to the atmosphere. We observed large shifts with time in the emission rate (from 170 to 16 ng N cm(-2) h(-1)) and in delta (15)N of N(2)O emitted (from -46 parts per thousand to +5 parts per thousand relative to atmospheric N(2)) from a urea-fertilized and irrigated agricultural field in Mexico. We calculated overall instantaneous enrichment factors for the sampling period, which suggest that the microbial N(2)O production shifts from nitrification (week 1)to denitrification (week 2). Isotopic signatures of N(2)O emissions were not always in accord with other proxies (such as NO/N(2)O emission ratio or water-filled pore space) used to estimate the relative importance of nitrification and denitrification as N(2)O sources. These observations strongly suggest that the soil surface emissions integrate processes occurring at different depths in the soil and a decoupling of NO and N(2)O production in this system. Further clues as to the source of N(2)O come from the positional dependence of (15)N in the emitted N(2)O, reported here for the first time in soil emissions. Enrichment at the central N position increased relative to the terminal N position by 9.3 parts per thousand during the first 4 days after irrigation, implying that nitrification preferentially enriches the central N position compared to denitrification. The overall delta (15)N signature we measured for N(2)O emitted from N-fertilized agricultural systems is more depleted than observed delta (15)N values for N(2)O emitted from more N-limited forest soils. Assuming that one half of the total agricultural N(2)O emissions associated with the global increase in soil nitrogen fertilizer use have an isotopic composition comparable to those of the agricultural fields reported here, we predict a decline in the isotopic signature of tropospheric N(2)O during this century of as much as 3 parts per thousand for (15)N. Although many uncertainties remain, we suggest that measurements of delta (15)N-N(2)O in fun air will provide constraints on how the N(2)O budget has changed during the past century. | |||||
BibTeX:
@article{perez_identifying_2001, author = {Pérez, T. and Trumbore, S. E. and Tyler, S. C. and Matson, P. A. and Ortiz-Monasterio, I. and Rahn, T. and Griffith, D. W. T.}, title = {Identifying the agricultural imprint on the global N2O budget using stable isotopes}, journal = {Journal of Geophysical Research}, year = {2001}, volume = {106}, number = {D9}, pages = {9869--9878}, url = {://WOS:000168731900017}, doi = {https://doi.org/10.1029/2000jd900809} } |
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Perez, T., Trumbore, S.E., Tyler, S.C., Davidson, E.A., Keller, M. and de Camargo, P.B. | Isotopic variability of N(2)O emissions from tropical forest soils | 2000 | Global Biogeochemical Cycles Vol. 14(2), pp. 525-535 |
article | DOI URL |
Abstract: We report measurements of the (15)N and (18)O signature of N(2)O emitted from tropical rain forest soils at the La Selva Biological station in Costa Rica and in the Fazenda Vitoria in the State of Para, Brazil. The delta(15)N values ranged from -34 to 2 parts per thousand with respect to atmospheric N(2), while delta(18)O values had a smaller range, from -4 to 18 parts per thousand with respect to atmospheric O(2). We attribute these large variations to differences in microbial production, consumption, and transport of N(2)O. In general the delta(15)N of N(2)O emissions from an Oxisol soil in Brazil were consistently enriched by similar to 20 parts per thousand in (15)N compared to those from Ultisol and Inceptisol soils in Costa Rica. Denitrification is the most likely source of N(2)O in both locations during the rainy season, and the (15)N of nitrate was similar in both locations. We attribute the overall variability in emitted (15)N to differences in the ratio of N(2)O:N(2) escaping from the soil to the atmosphere, with a larger fraction of the N(2)O reduced to N(2) at the Brazilian sites. We found light delta(15)N-N(2)O values associated with high N(2)O emissions in a fertilized agricultural site in Costa Rica and in a "hot spot" of high emissions in the forest site in Brazil. This result suggests that the increase of substrate availability might increase the fractionation associated with N(2)O production. Overall, the Brazilian Oxisol soils had the most enriched delta(15)N-N(2)O emissions yet measured from soils. if these are more representative of tropical soil emissions than the Costa Rica emissions, then the globally averaged delta(15)N-N(2)O tropical rain forest soil source is more enriched than previously estimated. The large variations in isotopic signature for N(2)O emissions demonstrate the potential utility of stable isotopes as tools for understanding the processes of N(2)O production and consumption in soils. | |||||
BibTeX:
@article{perez_isotopic_2000, author = {Perez, T. and Trumbore, S. E. and Tyler, S. C. and Davidson, E. A. and Keller, M. and de Camargo, P. B.}, title = {Isotopic variability of N(2)O emissions from tropical forest soils}, journal = {Global Biogeochemical Cycles}, year = {2000}, volume = {14}, number = {2}, pages = {525--535}, url = {://WOS:000087586100001}, doi = {https://doi.org/10.1029/1999gb001181} } |
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Perez, T., Garcia-Montiel, D., Trumbore, S., Tyler, S., De Camargo, P., Moreira, M., Piccolo, M. and Cerri, C. | Nitrous oxide nitrification and denitrification (15)N enrichment factors from Amazon forest soils | 2006 | Ecological Applications Vol. 16(6), pp. 2153-2167 |
article | DOI URL |
Abstract: The isotopic signatures of (15)N and (18)O in N(2)O emitted from tropical soils vary both spatially and temporally, leading to large uncertainty in the overall tropical source signature and thereby limiting the utility of isotopes in constraining the global N(2)O budget. Determining the reasons for spatial and temporal variations in isotope signatures requires that we know the isotope enrichment factors for nitrification and denitrification, the two processes that produce N(2)O in soils. We have devised a method for measuring these enrichment factors using soil incubation experiments and report results from this method for three rain forest soils collected in the Brazilian Amazon: soil with differing sand and clay content from the Tapajos National Forest (TNF) near Santarem, ParA, and Nova Vida Farm, Rondonia. The (15)N enrichment factors for nitrification and denitrification differ with soil texture and site: -111 parts per thousand +/- 12 parts per thousand and -31 parts per thousand +/- 11 parts per thousand for a clay-rich Oxisol (TNF), -102 parts per thousand +/- 5 parts per thousand and -45 parts per thousand +/- 5 parts per thousand for a sandier Ultisol (TNF), and -10.4 parts per thousand +/- 3.5 parts per thousand (enrichment factor for denitrification) for another Ultisol (Nova Vida) soil, respectively. We also show that the isotopomer site preference (delta(15)N(alpha) - delta(15)N(beta) where alpha indicates the central nitrogen atom and beta the terminal nitrogen atom in N(2)O) may allow differentiation between processes of production and consumption of N(2)O and can potentially be used to determine the contributions of nitrification and denitrification. The site preferences for nitrification and denitrification from the TNF-Ultisol incubated soils are: 4.2 parts per thousand +/- 8.4 parts per thousand and 31.6 parts per thousand +/- 8.1 parts per thousand, respectively. Thus, nitrifying and denitrifying bacteria populations under the conditions of our study exhibit significantly different (15)N site preference fingerprints. Our data set strongly suggests that N(2)O isotopomers can be used in concert with traditional N(2)O stable isotope measurements as constraints to differentiate microbial N(2)O processes in soil and will contribute to interpretations of the isotopic site preference N(2)O values found in the free troposphere. | |||||
BibTeX:
@article{perez_nitrous_2006, author = {Perez, Tibisay and Garcia-Montiel, Diana and Trumbore, Susan and Tyler, Stanley and De Camargo, Plino and Moreira, Marcelo and Piccolo, Marisa and Cerri, Carlos}, title = {Nitrous oxide nitrification and denitrification (15)N enrichment factors from Amazon forest soils}, journal = {Ecological Applications}, year = {2006}, volume = {16}, number = {6}, pages = {2153--2167}, url = {://WOS:000242849300008}, doi = {https://doi.org/10.1890/1051-0761(2006)016%5B2153:nonadn%5D2.0.co;2} } |
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Pereira, R., Zweede, J., Asner, G.P. and Keller, M. | Forest canopy damage and recovery in reduced-impact and conventional selective logging in eastern Para, Brazil | 2002 | Forest Ecology and Management Vol. 168(1-3), pp. 77-89 |
article | DOI URL |
Abstract: We investigated ground and canopy damage and recovery following conventional logging and reduced-impact logging (RIL) of moist tropical forest in the eastern Amazon of Brazil. Paired conventional and RIL blocks were selectively logged with a harvest intensity of approximately 23 m(3) ha(-1) (geometric volume) in the dry seasons (July-December) of 1996 and 1998. Ground damage (roads + skid trails + log decks) in the conventional logging treatments occupied 8.9-11.2% of total operational area. In contrast, ground damage in RIL treatments ranged from 4.6 to 4.8% of the total area. Forest canopy damage was assessed using gap fraction measurements collected with an automated optical canopy analyzer (LAI-2000; Licor Inc.) in March 1999. Canopy opening varied by time since logging. The recently logged (1998) blocks had integrated canopy gap fractions of 21.6 and 10.9% of total area for conventional and RIL blocks, respectively. The blocks logged in 1996 had more closed canopies with 16.5 and 4.9% gap fraction for conventional and RIL blocks, respectively. For comparison, undisturbed forest had a canopy gap fraction of 3.1%. Measurements of ground disturbance and gap fraction using the Licor LAI-2000 generally agree with other field evaluations of RIL and conventional logging. Detailed understanding of canopy structural changes resulting from different logging intensities are critical to the prospect of logging damage estimation using current and future remote sensing products. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{pereira_forest_2002, author = {Pereira, R. and Zweede, J. and Asner, G. P. and Keller, M.}, title = {Forest canopy damage and recovery in reduced-impact and conventional selective logging in eastern Para, Brazil}, journal = {Forest Ecology and Management}, year = {2002}, volume = {168}, number = {1-3}, pages = {77--89}, url = {://WOS:000177478900007}, doi = {https://doi.org/10.1016/s0378-1127(01)00732-0} } |
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Pereira, L.G. and Rutledge, S.A. | Diurnal cycle of shallow and deep convection for a tropical land and an ocean environment and its relationship to synoptic wind regimes | 2006 | Monthly Weather Review Vol. 134(10), pp. 2688-2701 |
article | DOI URL |
Abstract: The characteristics of shallow and deep convection during the Tropical Rainfall Measuring Mission/ Large-Scale Biosphere-Atmosphere Experiment in Amazonia (TRMM/LBA) and the Eastern Pacific Investigation of Climate Processes in the Coupled Ocean-Atmosphere System (EPIC) are evaluated in this study. Using high-quality radar data collected during these two tropical field experiments, the reflectivity profiles, rain rates, fraction of convective area, and fraction of rainfall volume in each region are examined. This study focuses on the diurnal cycle of shallow and deep convection for the identified wind regimes in both regions. The easterly phase in TRMM/LBA and the northerly wind regime in EPIC were associated with the strongest convection, indicated by larger rain rates, higher reflectivities, and deeper convective cores compared to the westerly phase in TRMM/LBA and the southerly regime in EPIC. The diurnal cycle results indicated that convection initiates in the morning and peaks in the afternoon during TRMM/LBA, whereas in the east Pacific the diurnal cycle of convection is very dependent on the wind regime. Deep convection in the northerly regime peaks around midnight, nearly 6 h before its southerly regime counterpart. Moreover, the northerly regime of EPIC was dominated by convective rainfall, whereas the southerly regime was dominated by stratiform rainfall. The diurnal variability was more pronounced during TRMM/LBA than in EPIC. Shallow convection was associated with 10% and 3% of precipitation during TRMM/LBA and EPIC, respectively. | |||||
BibTeX:
@article{pereira_diurnal_2006, author = {Pereira, L. Gustavo and Rutledge, Steven A.}, title = {Diurnal cycle of shallow and deep convection for a tropical land and an ocean environment and its relationship to synoptic wind regimes}, journal = {Monthly Weather Review}, year = {2006}, volume = {134}, number = {10}, pages = {2688--2701}, url = {://WOS:000241361900003}, doi = {https://doi.org/10.1175/mwr3181.1} } |
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Pereira, L., Bittencourt, P., Oliveira, R., Junior, M., Barros, F., Ribeiro, R. and Mazzafera, P. | Plant pneumatics: stem air flow is related to embolism - new perspectives on methods in plant hydraulics [BibTeX] |
2016 | New Phytologist Vol. 211(1), pp. 357-70 |
article | DOI |
BibTeX:
@article{pereira_plant_2016, author = {Pereira, L. and Bittencourt, P.R. and Oliveira, R.S. and Junior, M.B. and Barros, F.V. and Ribeiro, R.V. and Mazzafera, P.}, title = {Plant pneumatics: stem air flow is related to embolism - new perspectives on methods in plant hydraulics}, journal = {New Phytologist}, year = {2016}, volume = {211}, number = {1}, pages = {357--70}, doi = {https://doi.org/10.1111/nph.13905} } |
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Pereira, G., Cardozo, F., Silva, F., Moraes, E., Ferreira, N., Freitas, S., Shimabukuro, Y., Breunig, F. and Viana, D. | Determinação e Modelagem da Taxa de Consumo de Biomassa Queimada [BibTeX] |
2012 | Revista Brasileira de Meteorologia Vol. 27(1), pp. 13 - 22 |
article | |
BibTeX:
@article{pereira_determinacao_2012, author = {Pereira, G. and Cardozo, F.S. and Silva, F.B. and Moraes, E.C. and Ferreira, N.J. and Freitas, S.R. and Shimabukuro, Y.E. and Breunig, F.M. and Viana, D.R.}, title = {Determinação e Modelagem da Taxa de Consumo de Biomassa Queimada}, journal = {Revista Brasileira de Meteorologia}, year = {2012}, volume = {27}, number = {1}, pages = {13 -- 22} } |
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Pereira, A.J., Dias, M., Albrecht, R.I., Pereira, L.G.P., Gandu, A.W., Massambani, O., Tokay, A. and Rutledge, S. | Multisensor analysis of a squall line in the Amazon Region | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Mesoscale features of the 26 January 1999 squall line are described with measurements made during the field experiment in Rondonia, Brazil, in the wet season (WET) of the Amazon region (AMC) as part of the Large-Scale Biosphere-Atmosphere Experiment in the Amazon (LBA) and the Tropical Rainfall Measurement Mission (TRMM); henceforth referred to as the WET AMC and TRMM-LBA field experiment. The squall line moved through the experiment area from northeast to southwest with high rainfall rates in its leading edge and a poorly defined trailing stratiform precipitating area. Polarimetric and Doppler measurements from the Portable Polarimetric S-band Radar (S-POL) were analyzed in conjunction with surface and upper level data, satellite visible (VIS) and infrared (IR) measurements. These remote and local measurements of variables such as cloud spatial and temporal distribution, pressure, temperature, moisture, precipitation, and wind fields are consistent with each other as well as with similar mesoscale dynamics and thermodynamics features measured, analyzed, and modeled elsewhere [e. g., Rotunno et al., 1988; Garstang et al., 1994; Houze et al., 1990]. This tropical squall line is similar to its cousins in the midlatitudes with finer-scale structural and dynamic features such as rotation and divergence. Results suggest that the cold pool has its origins in midlevels between 400 and 600 hPa from where evaporative cooling and drop-dragging bring down colder air to the surface. The convective region is dominated by warm microphysics, while the stratiform region is dominated by cold microphysics. Moreover, both regions are characterized by monomodal drop spectra centered around 2.0 and 1.0 mm, respectively. Horizontal circulation associated with strong updrafts tends to increase cloud growth efficiency in the leading edge of the squall line. | |||||
BibTeX:
@article{pereira_multisensor_2002, author = {Pereira, A. J. and Dias, Mafs and Albrecht, R. I. and Pereira, L. G. P. and Gandu, A. W. and Massambani, O. and Tokay, A. and Rutledge, S.}, title = {Multisensor analysis of a squall line in the Amazon Region}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200064}, doi = {https://doi.org/10.1029/2000jd000305} } |
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Peixoto, R. | Uma rede operativa para efetivar o ZEE em territórios da Amazônia [BibTeX] |
2008 | Vol. 1Sociedade, Território e Conflitos: BR-163 em questão, pp. 265-297 |
incollection | |
BibTeX:
@incollection{castro_uma_2008, author = {Peixoto, R.}, title = {Uma rede operativa para efetivar o ZEE em territórios da Amazônia}, booktitle = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, pages = {265--297} } |
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Pedlowski, M.A., Matricardi, E.A.T., Skole, D., Cameron, S.R., Chomentowski, W., Fernandes, C. and Lisboa, A. | Conservation units: a new deforestation frontier in the Amazonian state of Rondonia, Brazil | 2005 | Environmental Conservation Vol. 32(2), pp. 149-155 |
article | DOI URL |
Abstract: Over the past several decades, the Brazilian State of Rondonia has been the destination of many rural migrants drawn from Brazil's middle southern regions by massive government colonization projects. Factors such as explosive population growth, logging, mining, small-scale farming and ranching have synergistically fuelled deforestation in the state. The total area deforested in Rondonia in 1978 was 4200 km(2). In 1988, the area increased to 30 000 km(2), in 1998 to 53 300 km(2) and by the year 2003, a total of 67 764 km(2) of Rondonia was deforested. In response to the high rate of deforestation observed in Rondonia and other Amazonian states, state and federal agencies worked to create a network of conservation units (CUs) in Brazil during the 1990s that was signed into law (Law 9985/00) in 2000. The ability of these CUs to reduce the rate of deforestation was analysed. Remotely-sensed data from Landsat and thematic coverages were used to measure deforestation inside all CUs in Rondonia. A more detailed analysis of CUs with the highest levels of deforestation, including an analysis between soil types and deforestation and a forecast of potential future deforestation, was conducted. The creation of conservation units in Rondonia has been useful in curbing deforestation within their boundaries; however, many CUs face pressure from the combined activities of illegal loggers, cattle ranchers and small-scale farmers seeking new sources of timber and agricultural land. For example, an exponential increase in the amount of deforestation was observed in Rondonia's Bom Futuro National Forest between 1992 and 2000. A regression model indicated a total of 20 500 ha deforested by 2002, while measurements from 2002 imagery showed an actual total deforestation of 20 720 ha. Should this trend persist, Bom Futuro National Forest could be completely deforested by 2017. CUs in Rondonia must be developed and implemented jointly by all stakeholders through the creation of partnerships between local communities, non-governmental organizations and government agencies. | |||||
BibTeX:
@article{pedlowski_conservation_2005, author = {Pedlowski, M. A. and Matricardi, E. A. T. and Skole, D. and Cameron, S. R. and Chomentowski, W. and Fernandes, C. and Lisboa, A.}, title = {Conservation units: a new deforestation frontier in the Amazonian state of Rondonia, Brazil}, journal = {Environmental Conservation}, year = {2005}, volume = {32}, number = {2}, pages = {149--155}, url = {://WOS:000232758000006}, doi = {https://doi.org/10.1017/s0376892905002134} } |
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Peacock, J., Baker, T.R., Lewis, S.L., Lopez-Gonzalez, G. and Phillips, O.L. | The RAINFOR database: monitoring forest biomass and dynamics | 2007 | Journal of Vegetation Science Vol. 18(4), pp. 535-542 |
article | DOI URL |
Abstract: Problem: Data from over 100 permanent sample plots which have been studied for 10-20 years need a suitable system for storage which allows simple data manipulation and retrieval for analysis. Methods: A relational database linking tree records, taxonomic nomenclature and corresponding environmental data has been built in MS Access as part of the RAINFOR project. Conclusion: The database allows flexible and long-term use of a large amount of data: more than 100 tree plots across Amazonia, incorporating over 80 000 records of individual trees and over 300 000 total records of tree diameter measurements from successive censuses. The database is designed to enable linkages to existing soil, floristic or plant-trait databases. This database will be a useful tool for exploring the impact of environmental factors on forest structure and dynamics at local to continental scales, and long term changes in forest ecology. As an early example of its potential, we explore the impact of different methodological assumptions on estimates of tropical forest biomass and carbon storage. | |||||
BibTeX:
@article{peacock_rainfor_2007, author = {Peacock, J. and Baker, T. R. and Lewis, S. L. and Lopez-Gonzalez, G. and Phillips, O. L.}, title = {The RAINFOR database: monitoring forest biomass and dynamics}, journal = {Journal of Vegetation Science}, year = {2007}, volume = {18}, number = {4}, pages = {535--542}, url = {://WOS:000246899200010}, doi = {https://doi.org/10.1111/j.1654-1103.2007.tb02568.x} } |
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Paulo, S., Cabral de Paulo, I. and Decker, Y. | Reconstructing the micrometeorological dynamics of the southern Amazonian transitional forest [BibTeX] |
2015 | Chaos Vol. 25, pp. 123123 |
article | |
BibTeX:
@article{paulo_reconstructing_2015, author = {Paulo, S.R. and Cabral de Paulo, I.J. and Decker, Y.}, title = {Reconstructing the micrometeorological dynamics of the southern Amazonian transitional forest}, journal = {Chaos}, year = {2015}, volume = {25}, pages = {123123} } |
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Pauliquevis, T., Lara, L.L., Antunes, M.L. and Artaxo, P. | Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution [BibTeX] |
2012 | Atmos. Chem. Phys. Vol. 12(11), pp. 4987-5015 |
article | DOI URL |
BibTeX:
@article{pauliquevis_aerosol_2012, author = {Pauliquevis, T. and Lara, L. L. and Antunes, M. L. and Artaxo, P.}, title = {Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution}, journal = {Atmos. Chem. Phys.}, year = {2012}, volume = {12}, number = {11}, pages = {4987--5015}, url = {https://acp.copernicus.org/articles/12/4987/2012/}, doi = {https://doi.org/10.5194/acp-12-4987-2012} } |
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Paula, J.D.d., Luizão, F.J. and Piedade, M.T.F. | The size distribution of organic carbon in headwater streams in the Amazon basin [BibTeX] |
2016 | Environ Sci Pollut Res. | article | DOI |
BibTeX:
@article{paula_size_2016, author = {Paula, Joana D’Arc de and Luizão, Flávio Jesus and Piedade, Maria Teresa Fernandez}, title = {The size distribution of organic carbon in headwater streams in the Amazon basin}, journal = {Environ Sci Pollut Res.}, year = {2016}, doi = {https://doi.org/10.1007/s11356-016-6041-6} } |
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Patino, S., Lloyd, J., Paiva, R., Baker, T.R., Quesada, C.A., Mercado, L.M., Schmerler, J., Schwarz, M., Santos, A.J.B., Aguilar, A., Czimczik, C.I., Gallo, J., Horna, V., Hoyos, E.J., Jimenez, E.M., Palomino, W., Peacock, J., Pena-Cruz, A., Sarmiento, C., Sota, A., Turriago, J.D., Villanueva, B., Vitzthum, P., Alvarez, E., Arroyo, L., Baraloto, C., Bonal, D., Chave, J., Costa, A.C.L., Herrera, R., Higuchi, N., Killeen, T., Leal, E., Luizao, F., Meir, P., Monteagudo, A., Neil, D., Nunez-Vargas, P., Penuela, M.C., Pitman, N., Priante Filho, N., Prieto, A., Panfil, S.N., Rudas, A., Salomao, R., Silva, N., Silveira, M., deAlmeida , S.S., Torres-Lezama, A., Vasquez-Martinez, R., Vieira, I., Malhi, Y. and Phillips, O.L. | Branch xylem density variations across the Amazon Basin | 2009 | Biogeosciences Vol. 6(4), pp. 545-568 |
article | DOI URL |
Abstract: Xylem density is a physical property of wood that varies between individuals, species and environments. It reflects the physiological strategies of trees that lead to growth, survival and reproduction. Measurements of branch xylem density, rho(x), were made for 1653 trees representing 598 species, sampled from 87 sites across the Amazon basin. Measured values ranged from 218 kg m(-3) for a Cordia sagotii (Boraginaceae) from Mountagne de Tortue, French Guiana to 1130 kg m(-3) for an Aiouea sp. (Lauraceae) from Caxiuana, Central Para, Brazil. Analysis of variance showed significant differences in average rho(x) across regions and sampled plots as well as significant differences between families, genera and species. A partitioning of the total variance in the dataset showed that species identity (family, genera and species) accounted for 33% with environment (geographic location and plot) accounting for an additional 26%; the remaining "residual" variance accounted for 41% of the total variance. Variations in plot means, were, however, not only accountable by differences in species composition because xylem density of the most widely distributed species in our dataset varied systematically from plot to plot. Thus, as well as having a genetic component, branch xylem density is a plastic trait that, for any given species, varies according to where the tree is growing in a predictable manner. Within the analysed taxa, exceptions to this general rule seem to be pioneer species belonging for example to the Urticaceae whose branch xylem density is more constrained than most species sampled in this study. These patterns of variation of branch xylem density across Amazonia suggest a large functional diversity amongst Amazonian trees which is not well understood. | |||||
BibTeX:
@article{patino_branch_2009, author = {Patino, S. and Lloyd, J. and Paiva, R. and Baker, T. R. and Quesada, C. A. and Mercado, L. M. and Schmerler, J. and Schwarz, M. and Santos, A. J. B. and Aguilar, A. and Czimczik, C. I. and Gallo, J. and Horna, V. and Hoyos, E. J. and Jimenez, E. M. and Palomino, W. and Peacock, J. and Pena-Cruz, A. and Sarmiento, C. and Sota, A. and Turriago, J. D. and Villanueva, B. and Vitzthum, P. and Alvarez, E. and Arroyo, L. and Baraloto, C. and Bonal, D. and Chave, J. and Costa, A. C. L. and Herrera, R. and Higuchi, N. and Killeen, T. and Leal, E. and Luizao, F. and Meir, P. and Monteagudo, A. and Neil, D. and Nunez-Vargas, P. and Penuela, M. C. and Pitman, N. and Priante Filho, N. and Prieto, A. and Panfil, S. N. and Rudas, A. and Salomao, R. and Silva, N. and Silveira, M. and deAlmeida, S. Soares and Torres-Lezama, A. and Vasquez-Martinez, R. and Vieira, I. and Malhi, Y. and Phillips, O. L.}, title = {Branch xylem density variations across the Amazon Basin}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {4}, pages = {545--568}, url = {://WOS:000265743200004 http://www.biogeosciences.net/6/545/2009/bg-6-545-2009.pdf}, doi = {https://doi.org/10.5194/bg-6-545-2009} } |
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Patino, S., Fyllas, N.M., Baker, T.R., Paiva, R., Quesada, C.A., Santos, A.J.B., Schwarz, M., ter Steege, H., Phillips, O.L. and Lloyd, J. | Coordination of physiological and structural traits in Amazon forest trees | 2012 | Biogeosciences Vol. 9(2), pp. 775-801 |
article | DOI URL |
Abstract: Many plant traits covary in a non-random manner reflecting interdependencies associated with "ecological strategy" dimensions. To understand how plants integrate their structural and physiological investments, data on leaf and leaflet size and the ratio of leaf area to sapwood area (Phi(LS)) obtained for 1020 individual trees (encompassing 661 species) located in 52 tropical forest plots across the Amazon Basin were incorporated into an analysis utilising existing data on species maximum height (H-max), seed size, leaf mass per unit area (M-A), foliar nutrients and delta C-13, and branch xylem density (rho(x)). Utilising a common principal components approach allowing eigenvalues to vary between two soil fertility dependent species groups, five taxonomically controlled trait dimensions were identified. The first involves primarily cations, foliar carbon and M-A and is associated with differences in foliar construction costs. The second relates to some components of the classic "leaf economic spectrum", but with increased individual leaf areas and a higher Phi(LS) newly identified components for tropical tree species. The third relates primarily to increasing H-max and hence variations in light acquisition strategy involving greater M-A, reductions in Phi(LS) and less negative delta C-13. Although these first three dimensions were more important for species from high fertility sites the final two dimensions were more important for low fertility species and were associated with variations linked to reproductive and shade tolerance strategies. Environmental conditions influenced structural traits with rho(x) of individual species decreasing with increased soil fertility and higher temperatures. This soil fertility response appears to be synchronised with increases in foliar nutrient concentrations and reductions in foliar [C]. Leaf and leaflet area and Phi(LS) were less responsive to the environment than rho(x). Thus, although genetically determined foliar traits such as those associated with leaf construction costs coordinate independently of structural characteristics such as maximum height, others such as the classical "leaf economic spectrum" covary with structural traits such as leaf size and Phi(LS). Coordinated structural and physiological adaptions are also associated with light acquisition/shade tolerance strategies with several traits such as M-A and [C] being significant components of more than one ecological strategy dimension. This is argued to be a consequence of a range of different potential underlying causes for any observed variation in such "ambiguous" traits. Environmental effects on structural and physiological characteristics are also coordinated but in a different way to the gamut of linkages associated with genotypic differences. | |||||
BibTeX:
@article{patino_coordination_2012, author = {Patino, S. and Fyllas, N. M. and Baker, T. R. and Paiva, R. and Quesada, C. A. and Santos, A. J. B. and Schwarz, M. and ter Steege, H. and Phillips, O. L. and Lloyd, J.}, title = {Coordination of physiological and structural traits in Amazon forest trees}, journal = {Biogeosciences}, year = {2012}, volume = {9}, number = {2}, pages = {775--801}, url = {://WOS:000300877400012}, doi = {https://doi.org/10.5194/bg-9-775-2012} } |
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Patel, N., Mounier, S., Guyot, J.L., Benamou, C. and Benaim, J.Y. | Fluxes of dissolved and colloidal organic carbon, along the Purus and Amazonas rivers ( Brazil) | 1999 | Science of the Total Environment Vol. 229(1-2), pp. 53-64 |
article | DOI URL |
Abstract: The first study of the molecular size distribution and fluxes of organic carbon from the Rio Purus to the Amazon River is reported. Organic carbon measurements using sequential tangential ultrafiltration (STUF) and discharge measurements give original information for the Purus basin, which has not been studied in depth until now. For this basin, the total organic carbon (TOC) values and the molecular size distribution are similar to those found for white waters. This type of water is the most common in the Amazonian basin and is characterised by a high concentration of mineral material and a low content of organic matter. In addition two sampling sites of the Purus River show a very large concentration (textgreater 80% of the TOC concentration) in the dissolved material. This distribution is similar to that of the Rio Madeira, which is unexpected, since the Rios Purus and Madeira do not drain the same kind of soil. For the Amazon basin, this work has confirmed the carbon size redistribution and flocculation/coagulation phenomena at the confluence. This dynamic exchange between the fractions is important for some phenomena such as metals transported by the organic matter. Indeed the metal transport and the molecular mass distribution of associated metals to organic matter are closely linked to the size of the organic material. (C) 1999 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{patel_fluxes_1999, author = {Patel, N. and Mounier, S. and Guyot, J. L. and Benamou, C. and Benaim, J. Y.}, title = {Fluxes of dissolved and colloidal organic carbon, along the Purus and Amazonas rivers ( Brazil)}, journal = {Science of the Total Environment}, year = {1999}, volume = {229}, number = {1-2}, pages = {53--64}, url = {://WOS:000081383400004}, doi = {https://doi.org/10.1016/s0048-9697(99)00069-8} } |
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Patade, S., Phillips, V.T.J., Amato, P., Bingemer, H.G., Burrows, S.M., DeMott, P.J., Goncalves, F.L.T., Knopf, D.A., Morris, C.E., Alwmark, C., Artaxo, P., Pöhlker, C., Schrod, J. and Weber, B. | Empirical Formulation for Multiple Groups of Primary Biological Ice Nucleating Particles from Field Observations over Amazonia [BibTeX] |
2021 | Journal of the Atmospheric Sciences Vol. 78(7), pp. 2195-2220 |
article | |
BibTeX:
@article{patade_empirical_2021, author = {Patade, Sachin and Phillips, Vaughan T. J. and Amato, Pierre and Bingemer, Heinz G. and Burrows, Susannah M. and DeMott, Paul J. and Goncalves, Fabio L. T. and Knopf, Daniel A. and Morris, Cindy E. and Alwmark, Carl and Artaxo, Paulo and Pöhlker, Christopher and Schrod, Jann and Weber, Bettina}, title = {Empirical Formulation for Multiple Groups of Primary Biological Ice Nucleating Particles from Field Observations over Amazonia}, journal = {Journal of the Atmospheric Sciences}, year = {2021}, volume = {78}, number = {7}, pages = {2195--2220} } |
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Passianoto, C.C., Ahrens, T., Feigl, B.J., Steudler, P.A., Melillo, J.M. and do Carmo, J.B. | Diurnal changes in nitric oxide emissions from conventional tillage and pasture sites in the Amazon Basin: influence of soil temperature | 2004 | Plant and Soil Vol. 258(1-2), pp. 21-29 |
article | DOI URL |
Abstract: We have investigated a subset of restoration practices applied to a degraded pasture at Fazenda Nova Vida, a 22 000 ha cattle ranch in Rondonia, Brazil. Nitric oxide (NO) and carbon dioxide (CO(2)) emissions from soils were measured in conventional tillage and current pasture sites to assess N and C losses. Mean daily NO emissions from tilled plots were at least twice those from the pasture. Nitric oxide emissions from the tilled sites showed a strong diurnal pattern, while those from the pasture sites did not. Mean daytime NO emissions from the tilled sites were 9.7 mug NO-N m(-2) h(-1), while mean nighttime emissions were 29.7 mug NO-N m(-2) h(-1). In the pasture sites, NO emissions were 7.6 mug NO-N m(-2) h(-1) during the day, and 7.7 mug NO-N m(-2) h(-1) at night. Surface soil temperature was a good inverse predictor (r(2) = 0.75) of NO emissions from the tilled sites. Carbon dioxide emissions from the tilled sites were generally larger than CO(2) emissions from the pasture sites. The mean CO(2) emission rate from the tilled sites was 179 mg C m(-2) h(-1), while it was 123 mg C m(-2) h(-1) from the pasture sites. There was no distinct diurnal pattern for CO(2) emissions. We found that the very high temperatures measured at the soil surface in the tillage plots, in the range of 40 - 45 degreesC, reduced the rate of NO emission. The reduction in NO emissions may be because of the sensitivity of autotrophic nitrifiers to high temperatures. This study provides insights on how land-use change may alter regional NO fluxes by exposing certain microbial communities to extreme environmental conditions. Future studies of NO emissions in tropical agricultural systems where soils are bare for extend periods need to make diurnal measurements or the daily fluxes will be substantially underestimated. | |||||
BibTeX:
@article{passianoto_diurnal_2004, author = {Passianoto, C. C. and Ahrens, T. and Feigl, B. J. and Steudler, P. A. and Melillo, J. M. and do Carmo, J. B.}, title = {Diurnal changes in nitric oxide emissions from conventional tillage and pasture sites in the Amazon Basin: influence of soil temperature}, journal = {Plant and Soil}, year = {2004}, volume = {258}, number = {1-2}, pages = {21--29}, url = {://WOS:000189012200004}, doi = {https://doi.org/10.1023/b:plso.0000016500.47714.30} } |
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Passianoto, C.C., Ahrens, T., Feigl, B.J., Steudler, P.A., do Carmo, J.B. and Melillo, J.M. | Emissions of CO(2), N(2)O, and NO in conventional and no-till management practices in Rondonia, Brazil | 2003 | Biology and Fertility of Soils Vol. 38(4), pp. 200-208 |
article | DOI URL |
Abstract: Efforts to restore productivity of pastures often employ agricultural management regimes involving either tillage or no-tillage options combined with various combinations of fertilizer application, herbicide use and the planting of a cash crop prior to the planting of forage grasses. Here we report on the emissions Of CO(2), N(2)O and NO from the initial phases (first 6 months) of three treatments in central Rondonia. The treatments were (1) control; (2) conventional tillage followed by planting of forage grass (Brachiaria brizantha) and fertilizer additions; (3) no-tillage/herbicide treatment followed by two plantings, the first being a cash crop of rice followed by forage grass. In treatment 3, the rice was fertilized. Relative to the control, tillage increased CO(2) emission by 37% over the first 2 months, while the no-tillage/herbicide regime decreased CO(2) emissions by 7% over the same period. The cumulative N(2)O emissions over the first 2 months from the tillage regime (0.94 kg N ha(-1)) were much higher than the N(2)O releases from either the no-tillage/herbicide regime (0.64 kg N ha(-1)) or the control treatment (0.04 kg N ha(-1)). The highest levels of N(2)O fluxes from both management regimes were observed following N fertilizations. The cumulative NO releases over the first 2 months were largest in the tillage treatment (0.98 kg N ha(-1)), intermediate in the no-tillage treatment (0.72 kg N ha(-1)), and smallest in the control treatment (0.12 kg N ha(-1)). For the first week following fertilization the percentage of fertilizer N lost as N(2)O Plus NO was 1.0% for the tillage treatment and 3.0% for the no-tillage treatment. | |||||
BibTeX:
@article{passianoto_emissions_2003, author = {Passianoto, C. C. and Ahrens, T. and Feigl, B. J. and Steudler, P. A. and do Carmo, J. B. and Melillo, J. M.}, title = {Emissions of CO(2), N(2)O, and NO in conventional and no-till management practices in Rondonia, Brazil}, journal = {Biology and Fertility of Soils}, year = {2003}, volume = {38}, number = {4}, pages = {200--208}, url = {://WOS:000185557700002}, doi = {https://doi.org/10.1007/s00374-003-0653-y} } |
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Parron, L.M., Cunha Bustamante, M.M. and Markewitz, D. | Fluxes of nitrogen and phosphorus in a gallery forest in the Cerrado of central Brazil | 2011 | Biogeochemistry Vol. 105(1-3), pp. 89-104 |
article | DOI URL |
Abstract: The Gallery forests of the Cerrado biome play a critical role in controlling stream chemistry but little information about biogeochemical processes in these ecosystems is available. This work describes the fluxes of N and P in solutions along a topographic gradient in a gallery forest. Three distinct floristic communities were identified along the gradient: a wet community nearest the stream, an upland dry community adjacent to the woodland savanna and an intermediate community between the two. Transects were marked in the three communities for sampling. Fluxes of N from bulk precipitation to these forests resulted in deposition of 12.6 kg ha(-1) y(-1) of total N of which 8.8 kg ha(-1) was as inorganic N. The throughfall flux of total N was generally textless 8.4 kg ha(-1) year(-1). Throughfall NO(3)-N fluxes were higher (7-32%) while NH(4)-N and organic N fluxes were lower (54-69% and 5-46%) than those in bulk precipitation. The throughfall flux was slightly lower for the wet forest community compared to other communities. Litter leachate fluxes differed among floristic communities with higher NH(4)-N in the wet community. The total N flux was greater in the wet forest than in the dry forest (13.5 vs. 9.4 kg ha(-1) year(-1), respectively). The stream water had total N flux of 0.3 kg ha(-1) year(-1). The flux of total P through bulk precipitation was 0.7 kg ha(-1) year(-1) while the mean fluxes of total P in throughfall (0.6 kg ha(-1) year(-1)) and litter leachate (0.5 kg ha(-1) year(-1)) declined but did not differ between communities. The low concentrations presented in soil solution and low fluxes in stream water (0.3 and 0.1 kg ha(-1) year(-1) for N and P, respectively) relative to other flowpaths emphasize the conservative nutrient cycling of these forests and the importance of internal recycling processes for the maintenance and conservation of riparian and stream ecosystems in the Cerrado. | |||||
BibTeX:
@article{parron_fluxes_2011, author = {Parron, Lucilia Maria and Cunha Bustamante, Mercedes Maria and Markewitz, Daniel}, title = {Fluxes of nitrogen and phosphorus in a gallery forest in the Cerrado of central Brazil}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {89--104}, url = {://WOS:000294501100007}, doi = {https://doi.org/10.1007/s10533-010-9537-z} } |
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Parolin, P., De Simone, O., Haase, K., Waldhoff, D., Rottenberger, S., Kuhn, U., Kesselmeier, J., Kleiss, B., Schmidt, W., Piedade, M.T.F. and Junk, W.J. | Central Amazonian floodplain forests: Tree adaptations in a pulsing system | 2004 | Botanical Review Vol. 70(3), pp. 357-380 |
article | DOI URL |
Abstract: Amazonian floodplain forests are characterized by an annual flood pulse with changes of the water table that exceed 10 meters. Seedlings and adult trees are waterlogged or submerged for continuous periods lasting up to seven months per year. The monomodal flood pulse of the rivers causes drastic changes in the bioavailability of nutrients, oxygen levels, and concentrations of phytotoxins. The aquatic phase occurs during a period in which temperature and light conditions are optimal for plant growth and development, implying the need for adaptations. Not only do trees persist in a dormant state, they grow vigorously during most of the year, including the aquatic period. The regularity of flooding may have enhanced the evolution of specific traits, which partially are well known from floodplain trees in other tropical and in temperate regions. Different kinds of adaptations are found at the level of structural, physiological, and phenological traits. Combinations of adaptations regarding seed germination, seedling development, and traits of roots, shoots, and leaves result in a variety of growth strategies among trees. These lead to specific species distributions and zonations along the flooding gradient and within Amazonian floodplain systems (nutrient-rich white-water varzea and nutrient-poor black-water igapo). | |||||
BibTeX:
@article{parolin_central_2004, author = {Parolin, P. and De Simone, O. and Haase, K. and Waldhoff, D. and Rottenberger, S. and Kuhn, U. and Kesselmeier, J. and Kleiss, B. and Schmidt, W. and Piedade, M. T. F. and Junk, W. J.}, title = {Central Amazonian floodplain forests: Tree adaptations in a pulsing system}, journal = {Botanical Review}, year = {2004}, volume = {70}, number = {3}, pages = {357--380}, url = {://WOS:000224795200003 http://www.bioone.org/doi/pdf/10.1663/0006-8101%282004%29070%5B0357%3ACAFFTA%5D2.0.CO%3B2}, doi = {https://doi.org/10.1663/0006-8101(2004)070%5B0357:caffta%5D2.0.co;2} } |
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Park, S., Pérez, T., Boering, K., Trumbore, S., Gil, J., Marquina, S. and Tyler, S. | Can N2O stable isotopes and isotopomers be useful tools to characterize sources and microbial pathways of N2O production and consumption in tropical soils? [BibTeX] |
2011 | Global Biogeochemical Cycles Vol. 25(GB1001), pp. doi:10.1029/2009GB003615 |
article | |
BibTeX:
@article{park_can_2011, author = {Park, S. and Pérez, T. and Boering, K.A. and Trumbore, S.E. and Gil, J. and Marquina, S. and Tyler, S.C.}, title = {Can N2O stable isotopes and isotopomers be useful tools to characterize sources and microbial pathways of N2O production and consumption in tropical soils?}, journal = {Global Biogeochemical Cycles}, year = {2011}, volume = {25}, number = {GB1001}, pages = {doi:10.1029/2009GB003615} } |
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Paralovo, S.L., Borillo, G.C., Barbosa, C.G., Godoi, A.F.L., Yamamoto, C.I., Souza, R.A.d., Andreoli, R.V., Costa, P.S., Almeida, G.P., Manzi, A.O., Pöhlker, C., Yáñez-Serrano, A.M., Kesselmeier, J. and Godoi, R.H. | Observations of atmospheric monoaromatic hydrocarbons at urban, semi-urban and forest environments in the Amazon region [BibTeX] |
2016 | Atmospheric Environment Vol. 128, pp. 175-184 |
article | |
BibTeX:
@article{paralovo_observations_2016, author = {Paralovo, Sarah L. and Borillo, Guilherme C. and Barbosa, Cybelli G.G. and Godoi, Ana Flavia L. and Yamamoto, Carlos I. and Souza, Rodrigo A.F. de and Andreoli, Rita V. and Costa, Patrícia S. and Almeida, Gerson P. and Manzi, Antonio O. and Pöhlker, Christopher and Yáñez-Serrano, Ana M. and Kesselmeier, Jürgen and Godoi, Ricardo H.M.}, title = {Observations of atmospheric monoaromatic hydrocarbons at urban, semi-urban and forest environments in the Amazon region}, journal = {Atmospheric Environment}, year = {2016}, volume = {128}, pages = {175--184} } |
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Paralovo, S.L., Barbosa, C.G., Carneiro, I.P., Kurzlop, P., Borillo, G.C., Schiochet, M.F.C., Godoi, A.F.L., Yamamoto, C.I., Souza, R.A.d., Andreoli, R.V., Ribeiro, I.O., Manzi, A.O., Kourtchev, I., Bustillos, J.O.V., Martin, S.T. and Godoi, R.H. | Observations of particulate matter, NO2, SO2, O3, H2S and selected VOCs at a semi-urban environment in the Amazon region [BibTeX] |
2019 | Science of the Total Environment Vol. 650, pp. 996-1006 |
article | |
BibTeX:
@article{paralovo_observations_2019, author = {Paralovo, Sarah L. and Barbosa, Cybelli G.G. and Carneiro, Isabela P.S. and Kurzlop, Priscila and Borillo, Guilherme C. and Schiochet, Maria Fernanda C. and Godoi, Ana Flavia L. and Yamamoto, Carlos I. and Souza, Rodrigo A.F. de and Andreoli, Rita V. and Ribeiro, Igor O. and Manzi, Antonio O. and Kourtchev, Ivan and Bustillos, Jose Oscar V. and Martin, Scot T. and Godoi, Ricardo H.M.}, title = {Observations of particulate matter, NO2, SO2, O3, H2S and selected VOCs at a semi-urban environment in the Amazon region}, journal = {Science of the Total Environment}, year = {2019}, volume = {650}, pages = {996--1006} } |
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Pan, W.K.Y., Walsh, S.J., Bilsborrow, R.E., Frizzelle, B.G., Erlien, C.M. and Baquero, F. | Farm-level models of spatial patterns of land use and land cover dynamics in the Ecuadorian Amazon | 2004 | Agriculture Ecosystems & Environment Vol. 101(2-3), pp. 117-134 |
article | DOI URL |
Abstract: Longitudinal studies examining socio-demographic and other contextual factors are vital to understanding landscape change. Landscape structure, function, and change are assessed for the northern Ecuadorian Amazon by examining the composition and spatial organization of deforestation, agricultural extensification, and secondary plant succession at the farm level in 1990 and 1999 through the integration of data from a satellite time-series, a longitudinal household survey, and GIS coverages. Pattern metrics were calculated at the farm level through the generation of a hybrid land use and land cover (LULC) digital classification of Landsat Thematic Mapper (TM) data. Population, labor, and other household variables were generated from a scientific sample of survey farms or fincas interviewed in 1990 and resurveyed in 1999. Topography, soils, and distance and geographic accessibility measures were derived for sample farms through a GIs as well as qualitative assessments from household surveys. Generalized linear mixed models (GLMMs) were generated for 155 and 157 fincas in 1990 and 1999, respectively, using pattern metrics at the landscape level as dependent variables, and biophysical, geographical, and socio-economic/demographic variables as independent variables. The models were derived to explore the changing nature of LULC at the finca level by assessing the variation in the spatial structure or organization of farm landscapes in 1990 and 1999, and the extent to which this variation could be explained by the available data. Results indicate rapid population growth causing substantial subdivision of plots, which in turn has created a more complex and fragmented landscape in 1999 than in 1990. Key factors predicting landscape complexity are population size and composition, plot fragmentation through subdivision, expansion of the road and electrical networks, age of the plot (1990 only), and topography. The research demonstrates that the process of combining data from household surveys, satellite time-series images, and GIs coverages provide an ideal framework to examine population-environment interactions and that the statistical models presented are powerful tools to combine such data in an integrated way. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{pan_farm-level_2004, author = {Pan, W. K. Y. and Walsh, S. J. and Bilsborrow, R. E. and Frizzelle, B. G. and Erlien, C. M. and Baquero, F.}, title = {Farm-level models of spatial patterns of land use and land cover dynamics in the Ecuadorian Amazon}, journal = {Agriculture Ecosystems & Environment}, year = {2004}, volume = {101}, number = {2-3}, pages = {117--134}, url = {://WOS:000189102200002}, doi = {https://doi.org/10.1016/j.agee.2003.09.022} } |
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Pan, W.K.Y. and Bilsborrow, R.E. | The use of a multilevel statistical model to analyze factors influencing land use: a study of the Ecuadorian Amazon | 2005 | Global and Planetary Change Vol. 47(2-4), pp. 232-252 |
article | DOI URL |
Abstract: This research introduces a novel application of a constrained multivariate response multilevel model of land use. Methodological objectives are (1) to examine the conceptual specification of a multilevel model of land use and (2) to incorporate constraints in multilevel model estimation to reflect the ipsative nature of land use as a response. The substantive objective is to demonstrate and report multilevel results from a representative sample of farm plots (fincas) in 1999 nested in 59 communities throughout the Northern Ecuadorian Amazon. Results indicate that population pressure, labor, and accessibility and proximity between households and communities are strong predictors of land use. Communities are seen to significantly influence land use at the finca level through unobserved and observed structural effects. We conclude with four recommendations to apply multilevel models: (1) consider alternative types of multilevel models to better match land use data distributions; (2) test and control for spatial autocorrelation; (3) collect the best data possible at higher levels; and (4) consider further integration of remotely sensed and household survey data using a multilevel framework. (c) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{pan_use_2005, author = {Pan, W. K. Y. and Bilsborrow, R. E.}, title = {The use of a multilevel statistical model to analyze factors influencing land use: a study of the Ecuadorian Amazon}, journal = {Global and Planetary Change}, year = {2005}, volume = {47}, number = {2-4}, pages = {232--252}, url = {://WOS:000231753100016}, doi = {https://doi.org/10.1016/j.gloplacha.2004.10.014} } |
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Palm, B.B., Sá, S.S.d., Day, D.A., Campuzano-Jost, P., Hu, W., Seco, R., Sjostedt, S.J., Park, J.-H. and Alex B. Guenther Joel Brito, F.W.P.A.R.T.J.W.L.D.Y.R.W.G.I.-V.A.H.G.Y.L.S.R.S.R.S.M.K.N.M.L.A.S.T.M.and.J.L.J.S.K. | Secondary organic aerosol formation from ambient air in an oxidation flow reactor in central Amazonia [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 467-493 |
article | DOI |
BibTeX:
@article{palm_secondary_2018, author = {Palm, Brett B. and Sá, Suzane S. de and Day, Douglas A. and Campuzano-Jost, Pedro and Hu, Weiwei and Seco, Roger and Sjostedt, Steven J. and Park, Jeong-Hoo and Alex B. Guenther, Joel Brito, Florian Wurm, Paulo Artaxo, Ryan Thalman, Jian Wang, Lindsay D. Yee, Rebecca Wernis, Gabriel Isaacman-VanWertz, Allen H. Goldstein, Yingjun Liu, Stephen R. Springston, Rodrigo Souza, Matt K. Newburn, M. Lizabeth Alexander, Scot T. Martin, and Jose L. Jimenez, Saewung Kim}, title = {Secondary organic aerosol formation from ambient air in an oxidation flow reactor in central Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {467--493}, doi = {https://doi.org/10.5194/acp-18-467-2018} } |
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Palácios, R.S., Sallo, F.S. and Nogueira, J.S. | Variability of Aerosol Optical Depth over Cerrado of Mato Grosso, Brazil [BibTeX] |
2016 | Applied Ecology and Environmental Research Vol. 4, pp. 96-102 |
article | |
BibTeX:
@article{palacios_variability_2016, author = {Palácios, R. S. and Sallo, F. S. and Nogueira, J. S.}, title = {Variability of Aerosol Optical Depth over Cerrado of Mato Grosso, Brazil}, journal = {Applied Ecology and Environmental Research}, year = {2016}, volume = {4}, pages = {96--102} } |
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Palácios, A., Cirino, P., G. G., N., Morais, V., F. G., R., L. D., B., M. S., M., N. G., C., L. F. A., M., J. B., &.N. and J. de S., R.d.S. | Long-term measurements of aerosol optical properties and radiative forcing (2011-2017) over Central Amazonia [BibTeX] |
2021 | Atmósfera Vol. 35(1), pp. 143-163 |
article | |
BibTeX:
@article{palacios_long-term_2021, author = {Palácios, Artaxo, P., Cirino, G. G., Nakale, V., Morais, F. G., Rothmund, L. D., Biudes, M. S., Machado, N. G., Curado, L. F. A., Marques, J. B., & Nogueira, J. de S., R. da S.}, title = {Long-term measurements of aerosol optical properties and radiative forcing (2011-2017) over Central Amazonia}, journal = {Atmósfera}, year = {2021}, volume = {35}, number = {1}, pages = {143--163} } |
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Palácios, R., Romera, K., Rizzo, L., Cirino, G., Adams, D., Imbiriba, B., Nassarden, D., Rothmund, L., Siqueira, A., Basso, J., Rodrigues, T., Curado, L., Weber, A., Nogueira, J., Morais, F. and Artaxo, P. | Optical properties and spectral dependence of aerosol light absorption over the Brazilian Pantanal | 2022 | Atmospheric Pollution Research Vol. 13(5), pp. 101413 |
article | DOI URL |
Abstract: Characterizing optical properties of aerosols, particularly the absorption processes, is fundamental for understanding the role of these particles in ecosystems as well as the climate, in general. Currently, changes in precipitation regimes in the southern Amazon basin have resulted in a considerable increase in biomass burning, whereby large amounts of aerosols and gases are emitted into the atmosphere. These increased emissions can impact the ecosystem, modifying mass and energy flows at the surface. This study, motivated by the need for more aerosol observations was the result of a long-term campaign carried out in the Brazilian Pantanal, which provided continuous in-situ measurements of aerosol optical properties between January 2017 and December 2019. From these data, optical properties of aerosols were quantified and analyzed seasonally. Corrected estimates for absorption coefficient (σabs) and Angstrom absorption exponent (αabs) were utilized to characterize the spectral dependence of absorption by aerosols. With additional measurements of the scattering coefficient (σscat), it was possible to evaluate the single scattering albedo (ω0). The mean values for σabs, σscat, ω0 at 525 nm and αabs 370–880 nm during the wet season were 0.66 ± 0.58 Mm−1, 6.16 ± 5.75 Mm−1, 0.90 ± 0.06 and 1.43 ± 0.49, respectively. These values, within measurement uncertainties, were similar to results found in the central Amazon. During the dry season, absorption and scattering increased approximately 88% and 86%, respectively, providing strong evidence for the contribution of local and regional emissions from biomass burning. The values of ω0 did not reveal significant seasonal differences, however, a sharp reduction was observed, medians below 0.8, at the beginning of the burning period, which was associated with more recent local burnings and, therefore, greater absorption. The mean values evaluated for different spectral intervals reveal a strong contribution of brown carbon (BrC) during the dry season, with medians of 1.78 and 0.87 for the intervals of 370–590 nm and 590–880 nm, respectively. This work also quantified BC concentrations for the dry and wet seasons, obtaining mean values of 0.75 ± 0.83 and 0.12 ± 0.09 μgm−3, respectively. In general, a striking similarity was encountered for aerosol optical properties between the Pantanal and the Central Amazon during the wet season. The results presented here characterize the background values for aerosol optical properties in the Pantanal, and the additional effects resulting from biomass burning emissions, therefore providing essential information to assess the effects these particles have on the ecosystem. | |||||
BibTeX:
@article{palacios_optical_2022, author = {Palácios, Rafael and Romera, Kelly and Rizzo, Luciana and Cirino, Glauber and Adams, David and Imbiriba, Breno and Nassarden, Danielle and Rothmund, Lucas and Siqueira, Angélica and Basso, João and Rodrigues, Thiago and Curado, Leone and Weber, Alfredo and Nogueira, José and Morais, Fernando and Artaxo, Paulo}, title = {Optical properties and spectral dependence of aerosol light absorption over the Brazilian Pantanal}, journal = {Atmospheric Pollution Research}, year = {2022}, volume = {13}, number = {5}, pages = {101413}, url = {https://www.sciencedirect.com/science/article/pii/S130910422200099X}, doi = {https://doi.org/10.1016/j.apr.2022.101413} } |
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Palace, M., Keller, M. and Silva, H. | Necromass production: Studies in undisturbed and logged Amazon forests | 2008 | Ecological Applications Vol. 18(4), pp. 873-884 |
article | DOI URL |
Abstract: Necromass stocks account for up to 20% of carbon stored in tropical forests and have been estimated to be 14-19% of the annual aboveground carbon flux. Both stocks and fluxes of necromass are infrequently measured. In this study, we directly measured the production of fallen coarse necromass (textgreater= 2 cm diameter) during 4.5 years using repeated surveys in undisturbed forest areas and in forests subjected to reduced-impact logging at the Tapajos National Forest, Belterra, Brazil (3.08 degrees S, 54.94 degrees W). We also measured fallen coarse necromass and standing dead stocks at two times during our study. The mean (SE) annual flux into the fallen coarse necromass pool in undisturbed forest of 6.7 (0.8) Mg.ha(-1).yr(-1) was not significantly different from the flux under a reduced-impact logging of 8.5 (1.3) Mg.ha(-1).yr(-1). With the assumption of steady state, the instantaneous decomposition constants for fallen necromass in undisturbed forests were 0.12 yr(-1) for large, 0.33 yr(-1) for medium, and 0.47 yr(-1) for small size classes. The mass weighted decomposition constant was 0.15 yr(-1) for all fallen coarse necromass. Standing dead wood had a residence time of 4.2 years, and similar to 0.9 Mg.ha(-1).yr(-1) of this pool was respired annually to the atmosphere through decomposition. Coarse necromass decomposition at our study site accounted for 12% of total carbon remineralization, and total aboveground coarse necromass was 14% of the aboveground biomass. Use of mortality rates to calculate production of coarse necromass leads to an underestimation of coarse necromass production by 45%, suggesting that nonlethal disturbance such as branch fall contributes significantly to this flux. Coarse necromass production is an important component of the tropical forest carbon cycle that has been neglected in most previous studies or erroneously estimated. | |||||
BibTeX:
@article{palace_necromass_2008, author = {Palace, Michael and Keller, Michael and Silva, Hudson}, title = {Necromass production: Studies in undisturbed and logged Amazon forests}, journal = {Ecological Applications}, year = {2008}, volume = {18}, number = {4}, pages = {873--884}, note = {Edition: 2008/06/10}, url = {://WOS:000256243200006}, doi = {https://doi.org/10.1890/06-2022.1} } |
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Palace, M., Keller, M., Asner, G.P., Silva, J.N.M. and Passos, C. | Necromass in undisturbed and logged forests in the Brazilian Amazon | 2007 | Forest Ecology and Management Vol. 238(1-3), pp. 309-318 |
article | DOI URL |
Abstract: Necromass is an important stock of carbon in tropical forests. We estimated volume, density, and mass of fallen and standing necromass in undisturbed and selectively logged forests at Juruena, Mato Grosso, Brazil (10.48 degrees S, 58.47 degrees W). We also measured standing dead trees at the Tapajos National Forest, Para, Brazil (3.08 degrees S, 54.94 degrees W) complementing our earlier study there on fallen necromass. We compared forest that was selectively logged using reduced-impact logging methods and undisturbed forest. We estimated necromass density accounting for void volume for necromass greater than 10 cm diameter at Juruena for five decay classes that ranged from freshly fallen (class 1) to highly decayed material (class 5). Average necromass density adjusted for void space (+/- S.E.) was 0.71 (0.02), 0.69 (0.04), 0.60 (0.04), 0.59 (0.06), and 0.33 (0.05) Mg m(-3) for classes 1 through 5, respectively. Small (2-5 cm) and medium (5-10 cm) size classes had densities of 0.52 (0.02) and 0.50 (0.04) Mg m(-3) respectively. The average dry mass (+/- S.E.) of fallen necromass at Juruena was 44.9 (0.2) and 67.0 (10.1) Mg ha(-1) for duplicate undisturbed and reduced impact logging sites, respectively. Small and medium sized material together accounted for 12-21% of the total fallen necromass at Juruena. At Juruena, the average mass of standing dead was 5.3 (1.0) Mg ha(-1) for undisturbed forest and 8.8 (2.3) Mg ha(-1) for forest logged with reduced impact methods. At Tapajos, standing dead average mass was 7.7 (2.0) Mg ha(-1) for undisturbed forest and 12.9 (4.6) Mg ha(-1) for logged forest. The proportion of standing dead to total fallen necromass was 12-17%. Even with reduced impact harvest management, logged forests had approximately 50% more total necromass than undisturbed forests. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{palace_necromass_2007, author = {Palace, Michael and Keller, Michael and Asner, Gregory P. and Silva, Jose Natalino M. and Passos, Carlos}, title = {Necromass in undisturbed and logged forests in the Brazilian Amazon}, journal = {Forest Ecology and Management}, year = {2007}, volume = {238}, number = {1-3}, pages = {309--318}, url = {://WOS:000243761700028}, doi = {https://doi.org/10.1016/j.foreco.2006.10.026} } |
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Palace, M., Keller, M., Asner, G.P., Hagen, S. and Braswell, B. | Amazon forest structure from IKONOS satellite data and the automated characterization of forest canopy properties | 2008 | Biotropica Vol. 40(2), pp. 141-150 |
article | DOI URL |
Abstract: We developed an automated tree crown analysis algorithm using 1-m panchromatic IKONOS satellite images to examine forest canopy structure in the Brazilian Amazon. The algorithm was calibrated on the landscape level with tree geometry and forest stand data at the Fazenda Cauaxi (3.75 degrees S, 48.37 degrees W)in the eastern Amazon, and then compared with forest stand data at Tapajos National Forest (3-08 degrees S, 54.94 degrees W) in the central Amazon. The average remotely sensed crown width (mean +/- SE) was 12.7 +/- 0.1 m (range: 2.0-34.0 m) and frequency of trees was 76.6 trees/ha at Cauaxi. At Tapajos, remotely sensed crown width was 13.1 +/- 10.1 m (range: 2.0-38.0 m) and frequency of trees was 76.4 trees/ha. At both Cauaxi and Tapajos, the remotely sensed average crown widths were within 3 percent of the crown widths derived from field measurements, although crown distributions showed significant differences between field-measured and automated methods. We used the remote sensing algorithm to estimate crown dimensions and forest structural properties in 51 forest stands (1 km(2)) throughout the Brazilian Amazon. The estimated crown widths, tree diameters (dbh), and stem frequencies differed widely among sites, while estimated biomass was similar among most sites. Sources of observed errors included an inability to detect understory crowns and to separate adjacent, intermingled crowns. Nonetheless, our technique can serve to provide information about structural characteristics of large areas of unsurveyed forest throughout Amazonia. | |||||
BibTeX:
@article{palace_amazon_2008, author = {Palace, Michael and Keller, Michael and Asner, Gregory P. and Hagen, Stephen and Braswell, Bobby}, title = {Amazon forest structure from IKONOS satellite data and the automated characterization of forest canopy properties}, journal = {Biotropica}, year = {2008}, volume = {40}, number = {2}, pages = {141--150}, url = {://WOS:000254195100002 http://onlinelibrary.wiley.com/store/10.1111/j.1744-7429.2007.00353.x/asset/j.1744-7429.2007.00353.x.pdf?v=1&t=h6hwj9m2&s=e83539066af9187d346f87827b6f86be8c4d65d5}, doi = {https://doi.org/10.1111/j.1744-7429.2007.00353.x} } |
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Pacifico, F., Folberth, G., Sitch, S., Haywood, J., Rizzo, L.V., Malavelle, F. and Artaxo, P. | Biomass burning related ozone damage on vegetation over the Amazon forest: a model sensitivity study [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 2791-2804 |
article | |
BibTeX:
@article{pacifico_biomass_2015, author = {Pacifico, F. and Folberth, G.A. and Sitch, S. and Haywood, J.M. and Rizzo, L. V. and Malavelle, F.F. and Artaxo, P.}, title = {Biomass burning related ozone damage on vegetation over the Amazon forest: a model sensitivity study}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {2791--2804} } |
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Paca, V.H.d.M., Espinoza-Dávalos, G.E., Hessels, T.M., Moreira, D.M., Comair, G.F. and Bastiaanssen, W.G.M. | The spatial variability of actual evapotranspiration across the Amazon River Basin based on remote sensing products validated with flux towers [BibTeX] |
2019 | Theor Appl Climatol Vol. 136, pp. 1209 |
article | |
BibTeX:
@article{paca_spatial_2019, author = {Paca, Victor Hugo da Motta and Espinoza-Dávalos, Gonzalo E. and Hessels, Tim M. and Moreira, Daniel Medeiros and Comair, Georges F. and Bastiaanssen, Wim G. M.}, title = {The spatial variability of actual evapotranspiration across the Amazon River Basin based on remote sensing products validated with flux towers}, journal = {Theor Appl Climatol}, year = {2019}, volume = {136}, pages = {1209} } |
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Paca, G., da Silva, R., Tapajós, R., dos Santos Gaspar A.B., V. and Espinoza-Dávalos | Remote Sensing Products Validated by Flux Tower Data in Amazon Rain Forest | 2022 | Remote Sensing Vol. 14(1259) |
article | DOI URL |
Abstract: … The installation of flux towers in the Amazon from The Large-Scale Biosphere–Atmosphere Experiment in Amazonia (LBA) [16] propelled the understanding of the different variables … | |||||
BibTeX:
@article{paca_remote_2022, author = {Paca, G.E.; da Silva, R.; Tapajós, R.; dos Santos Gaspar, A.B., V.H.d.M.; Espinoza-Dávalos}, title = {Remote Sensing Products Validated by Flux Tower Data in Amazon Rain Forest}, journal = {Remote Sensing}, year = {2022}, volume = {14}, number = {1259}, url = {https://www.mdpi.com/1528590}, doi = {https://doi.org/10.3390/rs14051259} } |
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Ozanne, C.M.P., Anhuf, D., Boulter, S.L., Keller, M., Kitching, R.L., Korner, C., Meinzer, F.C., Mitchell, A.W., Nakashizuka, T., Dias, P.L.S., Stork, N.E., Wright, S.J. and Yoshimura, M. | Biodiversity meets the atmosphere: A global view of forest canopies | 2003 | Science Vol. 301(5630), pp. 183-186 |
article | DOI URL |
Abstract: The forest canopy is the functional interface between 90% of Earth's terrestrial biomass and the atmosphere. Multidisciplinary research in the canopy has expanded concepts of global species richness, physiological processes, and the provision of ecosystem services. Trees respond in a species-specific manner to elevated carbon dioxide levels, while climate change threatens plant-animal interactions in the canopy and will likely alter the production of biogenic aerosols that affect cloud formation and atmospheric chemistry. | |||||
BibTeX:
@article{ozanne_biodiversity_2003, author = {Ozanne, C. M. P. and Anhuf, D. and Boulter, S. L. and Keller, M. and Kitching, R. L. and Korner, C. and Meinzer, F. C. and Mitchell, A. W. and Nakashizuka, T. and Dias, P. L. S. and Stork, N. E. and Wright, S. J. and Yoshimura, M.}, title = {Biodiversity meets the atmosphere: A global view of forest canopies}, journal = {Science}, year = {2003}, volume = {301}, number = {5630}, pages = {183--186}, note = {Edition: 2003/07/12}, url = {://WOS:000184056200032 http://www.sciencemag.org/content/301/5630/183}, doi = {https://doi.org/10.1126/science.1084507} } |
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Oyama, M. and Nobre, C. | A simple potential vegetation model for coupling with the Simple Biosphere Model (SiB) [BibTeX] |
2004 | Revista Brasileira de Meteorologia Vol. 19(2), pp. 203-216 |
article | |
BibTeX:
@article{oyama_simple_2004, author = {Oyama, M.D. and Nobre, C.A.}, title = {A simple potential vegetation model for coupling with the Simple Biosphere Model (SiB)}, journal = {Revista Brasileira de Meteorologia}, year = {2004}, volume = {19}, number = {2}, pages = {203--216} } |
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Oyama, M.D. and Nobre, C.A. | Climatic consequences of a large-scale desertification in northeast Brazil: A GCM simulation study | 2004 | Journal of Climate Vol. 17(16), pp. 3203-3213 |
article | DOI URL |
Abstract: The climatic impacts of a large-scale desertification in northeast Brazil (NEB) are assessed by using the Center for Weather Forecasting and Climate Studies-Center for Ocean-Land-Atmosphere Studies (CPTEC-COLA) AGCM. Two numerical runs are performed. In the control run, NEB is covered by its natural vegetation (most of NEB is covered by a xeromorphic vegetation known as caatinga); in the desertification run, NEB vegetation is changed to desert (bare soil). Each run consists of five 1-yr numerical integrations. The results for NEB wet season (March-May) are analyzed. Desertification results in hydrological cycle weakening: precipitation, evapotranspiration, moisture convergence, and runoff decrease. Surface net radiation decreases and this reduction is almost evenly divided between sensible and latent heat flux. Atmospheric diabatic heating decreases and subsidence anomalies confined at lower atmospheric levels are found. The climatic impacts result from the cooperative action of feedback processes related to albedo increase, plant transpiration suppression, and roughness length decrease. On a larger scale, desertification leads to precipitation increase in the oceanic belt close to the northernmost part of NEB (NNEB). In the NEB-NNEB dipole, the anomalies of vertical motion and atmospheric circulation are confined to lower atmospheric levels, that is, 850-700 hPa. At these levels, circulation anomalies resemble the linear baroclinic response of a shallow atmospheric layer (850-700 hPa) to a tropical heat sink placed over NEB at the middle-layer level. Therefore, NEB climate does show sensitivity to a vegetation change to desert. The present work shows the possibility of significant and pronounced climate impacts, on both regional and large scales, if the environmental degradation in NEB continues unchecked. | |||||
BibTeX:
@article{oyama_climatic_2004, author = {Oyama, M. D. and Nobre, C. A.}, title = {Climatic consequences of a large-scale desertification in northeast Brazil: A GCM simulation study}, journal = {Journal of Climate}, year = {2004}, volume = {17}, number = {16}, pages = {3203--3213}, url = {://WOS:000223374000011 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282004%29017%3C3203%3ACCOALD%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0442(2004)017%3C3203:ccoald%3E2.0.co;2} } |
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Oyama, M.D. and Nobre, C.A. | A new climate-vegetation equilibrium state for tropical South America | 2003 | Geophysical Research Letters Vol. 30(23) |
article | DOI URL |
Abstract: The existence of multiple climate-vegetation equilibria in Tropical South America is investigated under present-day climate conditions with the use of an atmospheric general circulation model coupled to a potential vegetation model. Two stable equilibria were found. One corresponds to the current biome distribution. The second is a new equilibrium state: savannas replace eastern Amazonian forests and a semi-desert area appears in the driest portion of Northeast Brazil. If sustainable development and conservation policies were not able to halt the increasing environmental degradation in those areas, then land use changes could, per se, tip the climate-vegetation system towards this new alternative drier stable equilibrium state, with savannization of parts of Amazonia and desertification of the driest area of Northeast Brazil, and with potential adverse impacts on the rich species diversity in the former region and water resources in the latter. | |||||
BibTeX:
@article{oyama_new_2003, author = {Oyama, M. D. and Nobre, C. A.}, title = {A new climate-vegetation equilibrium state for tropical South America}, journal = {Geophysical Research Letters}, year = {2003}, volume = {30}, number = {23}, url = {://WOS:000187481800004}, doi = {https://doi.org/10.1029/2003gl018600} } |
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Ometto, J., Nobre, A.D., Rocha, H.R., Artaxo, P. and Martinelli, L.A. | Amazonia and the modern carbon cycle: lessons learned | 2005 | Oecologia Vol. 143(4), pp. 483-500 |
article | DOI URL |
Abstract: In this paper, we review some critical issues regarding carbon cycling in Amazonia, as revealed by several studies conducted in the Large Scale Biosphere Atmosphere Experiment in Amazonia (LBA). We evaluate both the contribution of this magnificent biome for the global net primary productivity/net ecosystem exchange (NPP/NEE) and the feedbacks of climate change on the dynamics of Amazonia. In order to place Amazonia in a global perspective and make the carbon flux obtained through the LBA project comparable with global carbon budgets, we extrapolated NPP/NEE values found by LBA studies to the entire area of the Brazilian Amazon covered by rainforest. The carbon emissions due to land use changes for the tropical regions of the world produced values from 0.96 to 12.4 Pg C year(-1), while atmospheric CO2 inversion models have recently indicated that tropical lands in the Americas could be exchanging a net 0.62 +/- 1.15 Pg C year(-1) with the atmosphere. The difference calculated from these two methods would imply a local sink of approximately 1.6-1.7 Pg C year(-1), or a source of 0.85 ton C ha(-1) year(-1). Using our crude extrapolation of LBA values for the Amazon forests (5 million km(2)) we estimate a range for the C flux in the region of -3.0 to 0.75 Pg C year(-1). The exercise here does not account for environmental variability across the region, but it is an important driver for present and future studies linking local process (i.e. nutrient availability, photosynthetic capacity, and so forth) to global and regional dynamic approaches. | |||||
BibTeX:
@article{ometto_amazonia_2005, author = {Ometto, J.P.H.B. and Nobre, A. D. and Rocha, H. R. and Artaxo, P. and Martinelli, L. A.}, title = {Amazonia and the modern carbon cycle: lessons learned}, journal = {Oecologia}, year = {2005}, volume = {143}, number = {4}, pages = {483--500}, note = {Edition: 2005/04/01}, url = {://WOS:000229781100001 http://www.springerlink.com/content/v63525666m49h21g/fulltext.pdf}, doi = {https://doi.org/10.1007/s00442-005-0034-3} } |
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Ometto, J., Flanagan, L.B., Martinelli, L.A., Moreira, M.Z., Higuchi, N. and Ehleringer, J.R. | Carbon isotope discrimination in forest and pasture ecosystems of the Amazon Basin, Brazil | 2002 | Global Biogeochemical Cycles Vol. 16(4) |
article | DOI URL |
Abstract: [1] Our objective was to measure the stable carbon isotope composition of leaf tissue and CO2 released by respiration (delta(r)), and to use this information as an estimate of changes in ecosystem isotopic discrimination that occur in response to seasonal and interannual changes in environmental conditions, and land-use change (forest-pasture conversion). We made measurements in primary forest and pastures in the Amazon Basin of Brazil. At the Santarem forest site, delta(r) values showed a seasonal cycle varying from less than -29parts per thousand to approximately -26parts per thousand. The observed seasonal change in delta(r) was correlated with variation in the observed monthly precipitation. In contrast, there was no significant seasonal variation in delta(r) at the Manaus forest site (average delta(r) approximately -28parts per thousand), consistent with a narrower range of variation in monthly precipitation than occurred in Santarem. Despite substantial (9parts per thousand) vertical variation in leaf delta(13)C, the average delta(r) values observed for all forest sites were similar to the delta(13)C values of the most exposed sun foliage of the dominant tree species. This suggested that the major portion of recently respired carbon dioxide in these forests was metabolized carbohydrate fixed by the sun leaves at the top of the forest canopy. There was no significant seasonal variation observed in the delta(13)C values of leaf organic matter for the forest sites. We sampled in pastures dominated by the C-4 grass, Brachiaria spp., which is planted after forest vegetation has been cleared. The carbon isotope ratio of respired CO2 in pastures was enriched in C-13 by approximately 10parts per thousand compared to forest ecosystems. A significant temporal change occurred in delta(r) after the Manaus pasture was burned. Burning removed much of the encroaching C-3 shrub vegetation and so allowed an increased dominance of the C-4 pasture grass, which resulted in higher delta(r) values. | |||||
BibTeX:
@article{ometto_carbon_2002, author = {Ometto, J.P.H.B. and Flanagan, L. B. and Martinelli, L. A. and Moreira, M. Z. and Higuchi, N. and Ehleringer, J. R.}, title = {Carbon isotope discrimination in forest and pasture ecosystems of the Amazon Basin, Brazil}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {4}, url = {://WOS:000181062200002 http://www.agu.org/pubs/crossref/2002/2001GB001462.shtml}, doi = {https://doi.org/10.1029/2001gb001462} } |
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Ometto, J.P.H.B., Ehleringer, J.R., Domingues, T.F., Berry, J.A., Ishida, F.Y., Mazzi, E., Higuchi, N., Flanagan, L.B., Nardoto, G.B. and Martinelli, L.A. | The stable carbon and nitrogen isotopic composition of vegetation in tropical forests of the Amazon Basin, Brazil | 2006 | Biogeochemistry Vol. 79(1-2), pp. 251-274 |
article | DOI URL |
Abstract: Here we present the within-site, seasonal, and interannual variations of the carbon (delta C-13) and nitrogen (delta N-15) isotope ratios of leaves, wood, bark and litter from four sites in the Amazon region, Brazil. Samples were collected in Manaus (3 degrees 06'07"S; 60 degrees 01'30" W), Ji-Parana (10 degrees 53'07"S; 61 degrees 57'06" W), and Santarem (2 degrees 26'35" S; 54 degrees 42'30" W) with mean annual precipitation of 2207, 2040 and 1909 mm respectively. The overall average for all leaf samples was -32.3 +/- 2.5 parts per thousand for delta C-13 and +/- 5.8 +/- 1.6 parts per thousand for delta N-15 (n=756). The leaf delta values at these sites were often but not always statistically distinct from each other. The delta C-13 values varied from -37.8 parts per thousand to -25.9 parts per thousand. Pronounced differences in delta C-13 values occurred with height associated with differences in forest structure. The delta C-13 of leaf dry matter showed seasonal variations associated with the length of the dry season, despite the fact that total annual precipitation was similar among the studied sites. Leaf delta N-15 values ranged from +/- 0.9 parts per thousand to a maximum value of +10.9 parts per thousand, and the Santarem sites showed more enriched values than Manaus and Ji-Parana sites. No seasonal variation was detected in the delta N-15 of leaves, but significant differences were observed among sites and with changes in canopy height. The isotope ratio data are consistent with our current understanding of the roles of light, water availability, and recycling of soil-respired CO2 influences on delta C-13 and consistent with our understanding that an open nitrogen cycle can lead to high delta N-15 values despite a significant number of legumes in the vegetation. | |||||
BibTeX:
@article{ometto_stable_2006, author = {Ometto, Jean P. H. B. and Ehleringer, James R. and Domingues, Tomas F. and Berry, Joseph A. and Ishida, Francoise Y. and Mazzi, Edmar and Higuchi, Niro and Flanagan, Lawrence B. and Nardoto, Gabriela B. and Martinelli, Luiz A.}, title = {The stable carbon and nitrogen isotopic composition of vegetation in tropical forests of the Amazon Basin, Brazil}, journal = {Biogeochemistry}, year = {2006}, volume = {79}, number = {1-2}, pages = {251--274}, url = {://WOS:000240033100013}, doi = {https://doi.org/10.1007/s10533-006-9008-8} } |
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Ometto, J.P.H., Flanagan, L.B., Martinelli, L.A. and Ehleringer, J.R. | Oxygen isotope ratios of waters and respired CO2 in Amazonian forest and pasture ecosystems | 2005 | Ecological Applications Vol. 15(1), pp. 58-70 |
article | DOI URL |
Abstract: The oxygen isotope ratio (delta(18)O, SMOW) of atmospheric CO, is a powerful indicator of large-scale CO, exchange on land. Oxygen isotopic exchange between CO, and water in leaves and soils controls the delta(18)O of atmospheric CO, Currently there is little empirical information on the spatial and temporal variation in the delta(18)O of leaf and stem water in tropical ecosystems. We measured the seasonal dynamics of delta(18)O in atmospheric CO, and water in different ecosystem compartments in both primary forest and pasture ecosystems in three different regions of the Amazonian Basin of Brazil (Ji-Parana, Manaus, and Santarem). Within regions, the source (stem) water delta(18)O values for primary forests and pastures were similar;, neither vegetation type exhibited distinct wet-dry season patterns. Daytime leaf water isotope ratios were strongly correlated with predictions of the Craig-Gordon model. The delta(18)O value of leaf water was positively correlated with leaf height above ground because of associated variation in vapor pressure deficit and the delta(18)O of atmospheric water vapor within forest canopies. Consistent with these observations, the delta(18)O value of leaf cellulose was positively correlated with forest height. Leaf water from pasture grasses was more 180 enriched than leaf water from forest vegetation. There was a tendency for daytime leaf water to be more enriched in 180 during the dry season, reflecting generally lower humidity conditions during the dry season. Nighttime measurements of the oxygen isotope ratio of ecosystem respired CO2 in both forest and pasture vegetation were not consistent with values expected for CO2 in equilibrium with stem (soil) water, despite nighttime vapor pressure deficits close to. zero. Apparently, the delta(18)O of leaf water lagged and did not attain isotopic equilibrium at night. Thus, the deviation of nighttime delta(18)O values of ecosystem respiration from that expected from a CO2 efflux in equilibrium with soil (stem) water increased as delta(18)O values of ecosystem respiration became 180 enriched. Discrimination against CO2 containing 110 (DeltaC(18)OO) during photosynthesis was calculated based on measured leaf water delta(18)O values. Forests had consistently higher modeled DeltaC(18)OO values than pastures. The daytime isotope effects we calculate for photosynthesis and respiration were consistent with previous model predictions of a strong depletion of 110 in atmospheric CO2 over the Amazon Basin of Brazil. | |||||
BibTeX:
@article{ometto_oxygen_2005, author = {Ometto, J. P. H. and Flanagan, L. B. and Martinelli, L. A. and Ehleringer, J. R.}, title = {Oxygen isotope ratios of waters and respired CO2 in Amazonian forest and pasture ecosystems}, journal = {Ecological Applications}, year = {2005}, volume = {15}, number = {1}, pages = {58--70}, url = {://WOS:000227120700005}, doi = {https://doi.org/10.1890/03-5047} } |
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Ometto, J.P., Sousa-Neto, E.R. and Tejada, G. | Land Use, Land Cover and Land Use Change in the Brazilian Amazon (1960–2013) [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 369-383 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_land_2016, author = {Ometto, Jean P. and Sousa-Neto, Eráclito R. and Tejada, Graciela}, title = {Land Use, Land Cover and Land Use Change in the Brazilian Amazon (1960–2013)}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {369--383}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Ometto, J.P., Aguiar, A.P., Assis, T., Soler, L., Valle, P., Tejada, G., Lapola, D.M. and Meir, P. | Amazon forest biomass density maps: tack ling the uncertainty in carbon emission estimates [BibTeX] |
2014 | Climatic Change Vol. 124(3), pp. 545-560 |
article | DOI |
BibTeX:
@article{ometto_amazon_2014, author = {Ometto, Jean Pierre and Aguiar, Ana Paula and Assis, Talita and Soler, Luciana and Valle, Pedro and Tejada, Graciela and Lapola, David M. and Meir, P.}, title = {Amazon forest biomass density maps: tack ling the uncertainty in carbon emission estimates}, journal = {Climatic Change}, year = {2014}, volume = {124}, number = {3}, pages = {545--560}, doi = {https://doi.org/10.1007/s1058} } |
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Oliveras, I., Anderson, L. and Malhi, Y. | Application of remote sensing to understanding fire regimes and biomass burning emissions of Tropical Andes [BibTeX] |
2014 | Global Biogeochemical Cycles Vol. 28(4), pp. 480-496 |
article | DOI |
BibTeX:
@article{oliveras_application_2014, author = {Oliveras, I. and Anderson, L.O. and Malhi, Y.}, title = {Application of remote sensing to understanding fire regimes and biomass burning emissions of Tropical Andes}, journal = {Global Biogeochemical Cycles}, year = {2014}, volume = {28}, number = {4}, pages = {480--496}, doi = {https://doi.org/10.1002/2013GB004664} } |
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Oliver, B., Hannah, C., Ingrid, C., Antonio Lola, d.C. and Patrick, M. | Measuring the vertical profile of leaf wetness in a forest canopy | 2021 | MethodsX Vol. 8, pp. 101332 |
article | DOI URL |
Abstract: Plant canopies are wet for substantial amounts of time and this influences physiological performance and fluxes of energy, carbon and water at the ecosystem level. Leaf wetness sensors enable us to quantify the duration of leaf wetness and spatially map this to canopy structure. However, manually analysing leaf wetness data from plot-level experiments can be time-consuming, and requires a degree of subjective judgement in delineating wetness events which can lead to inconsistencies in the analysis. Here we:•Describe how to set up an array of leaf wetness sensors (Phytos 31, Meter) enabling the measurement of leaf wetness duration through the profile of a forest canopy,•Present a method and R script to objectively identify and distinguish periods of rain and dew from the output of leaf wetness sensors,•Provide a criteria for separating the leaf wetness sensor output into dew and rain events which may form a reference standard, or be modified for use, in future studies. | |||||
BibTeX:
@article{oliver_measuring_2021, author = {Oliver, Binks and Hannah, Carle and Ingrid, Coughlin and Antonio Lola, da Costa and Patrick, Meir}, title = {Measuring the vertical profile of leaf wetness in a forest canopy}, journal = {MethodsX}, year = {2021}, volume = {8}, pages = {101332}, url = {https://www.sciencedirect.com/science/article/pii/S2215016121001254}, doi = {https://doi.org/10.1016/j.mex.2021.101332} } |
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Oliveira, R.S., Dawson, T.E., Burgess, S.S.O. and Nepstad, D.C. | Hydraulic redistribution in three Amazonian trees | 2005 | Oecologia Vol. 145(3), pp. 354-363 |
article | DOI URL |
Abstract: About half of the Amazon rainforest is subject to seasonal droughts of 3 months or more. Despite this drought, several studies have shown that these forests, under a strongly seasonal climate, do not exhibit significant water stress during the dry season. In addition to deep soil water uptake, another contributing explanation for the absence of plant water stress during drought is the process of hydraulic redistribution; the nocturnal transfer of water by roots from moist to dry regions of the soil profile. Here, we present data on patterns of soil moisture and sap flow in roots of three dimorphic-rooted species in the Tapajos Forest, Amazonia, which demonstrate both upward (hydraulic lift) and downward hydraulic redistribution. We measured sap flow in lateral and tap roots of our three study species over a 2-year period using the heat ratio method, a sap-flow technique that allows bi-directional measurement of water flow. On certain nights during the dry season, reverse or acropetal flow (i.e.,in the direction of the soil) in the lateral roots and positive or basipetal sap flow (toward the plant) in the tap roots of Coussarea racemosa (caferana), Manilkara huberi (macaranduba) and Protium robustum (breu) were observed, a pattern consistent with upward hydraulic redistribution (hydraulic lift). With the onset of heavy rains, this pattern reversed, with continuous night-time acropetal sap flow in the tap root and basipetal sap flow in lateral roots, indicating water movement from wet top soil to dry deeper soils (downward hydraulic redistribution). Both patterns were present in trees within a rainfall exclusion plot (Seca Floresta) and to a more limited extent in the control plot. Although hydraulic redistribution has traditionally been associated with arid or strongly seasonal environments, our findings now suggest that it is important in ameliorating water stress and improving rain infiltration in Amazonian rainforests. This has broad implications for understanding and modeling ecosystem process and forest function in this important biome. | |||||
BibTeX:
@article{oliveira_hydraulic_2005, author = {Oliveira, R. S. and Dawson, T. E. and Burgess, S. S. O. and Nepstad, D. C.}, title = {Hydraulic redistribution in three Amazonian trees}, journal = {Oecologia}, year = {2005}, volume = {145}, number = {3}, pages = {354--363}, note = {Edition: 2005/08/11}, url = {://WOS:000232401800002}, doi = {https://doi.org/10.1007/s00442-005-0108-2} } |
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Oliveira, R.S., Bezerra, L., Davidson, E.A., Pinto, F., Klink, C.A., Nepstad, D.C. and Moreira, A. | Deep root function in soil water dynamics in cerrado savannas of central Brazil | 2005 | Functional Ecology Vol. 19(4), pp. 574-581 |
article | DOI URL |
Abstract: 1. Water is a key resource in tropical savannas. Changes in vegetation structure due to land-use change and increased fire frequency may affect the availability of water and the flux of water through these ecosystems. 2. We compared the seasonal soil moisture dynamics of two adjacent savanna ecosystems with contrasting tree densities in central Brazil. Our goal was to investigate the influence of tree density on deep water uptake, soil water dynamics and evapotranspiration. 3. Soil water was measured using a depth of 7.5 m beneath the tree-dominated cerrado denso ecosystem and to 4 m beneath the grass-dominated campo sujo ecosystem. Plant-available water (PAW) throughout the cerrado denso soil profile ranged from 293 mm at the end of the dry season to 689 mm during the wet season. In the grass-dominated site, PAW in the profile ranged from 155 to 362 mm. 4. During the dry season, approximate to 82% of the water used in cerrado denso and 67% in campo sujo was extracted from the profile below 1 m. The tree-dominated cerrado denso used 137 mm more water than the grass-dominated campo sujo. Significant deep soil water uptake was also observed during the wet season of 1998, when rainfall was below average. 5. Evapotranspiration (ET) rates (estimated as change in soil moisture over time) were higher in cerrado denso than in campo sujo during both seasons. Estimated ET ranged from 1.4 mm day(-1) during the dry season to 5.8 mm day(-1) for the wet season in cerrado denso, and from 0.9 mm day(-1) in the dry season to 4.5 mm day(-1) in early wet season in campo sujo. The differences in PAW and ET rates between the two ecosystems are associated not only with differences in root distribution, but also with differences in tree densities and the phenology of full-leaf canopies. 6. Our results suggest that deep-rooted plants may contribute significantly to the water balance of cerrado ecosystems, and that the hydrological cycle of this biome could change as woody vegetation is replaced by exotic grasses and agricultural crops. | |||||
BibTeX:
@article{oliveira_deep_2005, author = {Oliveira, R. S. and Bezerra, L. and Davidson, E. A. and Pinto, F. and Klink, C. A. and Nepstad, D. C. and Moreira, A.}, title = {Deep root function in soil water dynamics in cerrado savannas of central Brazil}, journal = {Functional Ecology}, year = {2005}, volume = {19}, number = {4}, pages = {574--581}, url = {://WOS:000231397300005}, doi = {https://doi.org/10.1111/j.1365-2435.2005.01003.x} } |
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Oliveira, P.J. and Fisch, G. | Perfil de vento em áreas de floresta e pastagem na Amazônia [BibTeX] |
2001 | Acta Amazonica Vol. 31, pp. 581-595 |
article | |
BibTeX:
@article{oliveira_perfil_2001, author = {Oliveira, P. J. and Fisch, G.}, title = {Perfil de vento em áreas de floresta e pastagem na Amazônia}, journal = {Acta Amazonica}, year = {2001}, volume = {31}, pages = {581--595} } |
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Oliveira, P.J. and Fisch, G. | Efeito da turbulência na camada limite atmosférica em áreas de floresta e pastagem na Amazônia [BibTeX] |
2000 | Revista Brasileira de Meteorologia Vol. 15, pp. 39-44 |
article | |
BibTeX:
@article{oliveira_efeito_2000, author = {Oliveira, P. J. and Fisch, G.}, title = {Efeito da turbulência na camada limite atmosférica em áreas de floresta e pastagem na Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2000}, volume = {15}, pages = {39--44} } |
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Oliveira Rocha, E., Fisch, G. and Kruijt B. & Ribeiro, J.P. | Efeitos de um evento de friagem nas condições meteorológicas na Amazônia: um estudo de caso [BibTeX] |
2004 | Acta Amazonica Vol. 34, pp. 613-619 |
article | |
BibTeX:
@article{oliveira_efeitos_2004, author = {Oliveira, Rocha, E.J.P.; Fisch, G.; Kruijt, B. & Ribeiro, J.B.M., P.J.}, title = {Efeitos de um evento de friagem nas condições meteorológicas na Amazônia: um estudo de caso}, journal = {Acta Amazonica}, year = {2004}, volume = {34}, pages = {613--619} } |
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Oliveira, P.H.F., Artaxo, P., Pires, C., De Lucca, S., Procopio, A., Holben, B., Schafer, J., Cardoso, L.F., Wofsy, S.C. and Rocha, H.R. | The effects of biomass burning aerosols and clouds on the CO2 flux in Amazonia | 2007 | Tellus Series B-Chemical and Physical Meteorology Vol. 59(3), pp. 338-349 |
article | DOI URL |
Abstract: Aerosol particles associated with biomass burning emissions affect the surface radiative budget and net ecosystem exchange (NEE) over large areas in Amazonia during the dry season. We analysed CO2 fluxes as a function of aerosol loading for two forest sites in Amazonia as part of the LBA experiment. Aerosol optical thickness (AOT) measurements were made with AERONET sun photometers, and CO2 flux measurements were determined by eddy-correlation. The enhancement of the NEE varied with different aerosol loading, as well as cloud cover, solar elevation angles and other parameters. The AOT value with the strongest effect on the NEE in the FLONA-Tapajos site was 1.7, with an enhancement of the NEE of 11% compared with clear-sky conditions. In the RBJ site, the strongest effect was for AOT of 1.6 with an enhancement of 18% in the NEE. For values of AOT lager than 2.7, strong reduction on the NEE was observed due to the reduction in the total solar radiation. The enhancement in the NEE is attributed to the increase of diffuse versus direct solar radiation. Due to the fact that aerosols from biomass burning are present in most tropical areas, its effects on the global carbon budget could also be significant. | |||||
BibTeX:
@article{oliveira_effects_2007, author = {Oliveira, Paulo H. F. and Artaxo, Paulo and Pires, Carlos and De Lucca, Silvia and Procopio, Aline and Holben, Brent and Schafer, Joel and Cardoso, Luiz F. and Wofsy, Steven C. and Rocha, Humberto R.}, title = {The effects of biomass burning aerosols and clouds on the CO2 flux in Amazonia}, journal = {Tellus Series B-Chemical and Physical Meteorology}, year = {2007}, volume = {59}, number = {3}, pages = {338--349}, url = {://WOS:000247174300002}, doi = {https://doi.org/10.1111/j.1600-0889.2007.00270.x} } |
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Oliveira, A., O. C., S., Tsokankunku, M., Wolff, A., Araújo, S., A. C., S., R. A. F., S., M. O., M., A. O., A. and M. O., P.E.S. | Nighttime wind and scalar variability within and above an Amazonian canopy [BibTeX] |
2018 | Atmospheric Chemistry and Physics Vol. 18(5), pp. 3083-3099 |
article | DOI |
BibTeX:
@article{oliveira_nighttime_2018, author = {Oliveira, Acevedo, O. C., Sörgel, M., Tsokankunku, A., Wolff, S., Araújo, A. C., Souza, R. A. F., Sá, M. O., Manzi, A. O., Andreae, M. O., P. E. S.}, title = {Nighttime wind and scalar variability within and above an Amazonian canopy}, journal = {Atmospheric Chemistry and Physics}, year = {2018}, volume = {18}, number = {5}, pages = {3083--3099}, doi = {https://doi.org/10.5194/acp-18-3083-2018} } |
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Oliveira, M.I., Acevedo, O.C., Sörgel, M., Nascimento, E.L., Manzi, A.O., Oliveira, P.E.S., Brondani, D.V., Tsokankunku, A. and Andreae, M.O. | Planetary boundary layer evolution over the Amazon rainforest in episodes of deep moist convection at the Amazon Tall Tower Observatory [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20, pp. 15-27 |
article | DOI |
BibTeX:
@article{oliveira_planetary_2020, author = {Oliveira, Maurício I. and Acevedo, Otávio C. and Sörgel, Matthias and Nascimento, Ernani L. and Manzi, Antonio O. and Oliveira, Pablo E. S. and Brondani, Daiane V. and Tsokankunku, Anywhere and Andreae, Meinrat O.}, title = {Planetary boundary layer evolution over the Amazon rainforest in episodes of deep moist convection at the Amazon Tall Tower Observatory}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, pages = {15--27}, doi = {https://doi.org/10.5194/acp-20-15-2020} } |
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Oliveira, A., O. C., S., Nascimento, M., E. L., M., A. O., O., P. E. S., B., D. V., T., Andreae, A. and M. O., M.I. | Planetary boundary layer evolution over the Amazon rain forest in episodes of deep moist convection at ATTO [BibTeX] |
2019 | Atmospheric Chemistry and Physics Discussions. | article | DOI |
BibTeX:
@article{oliveira_planetary_2019, author = {Oliveira, Acevedo, O. C., Sörgel, M., Nascimento, E. L., Manzi, A. O., Oliveira, P. E. S., Brondani, D. V., Tsokankunku, A., Andreae, M. O., M. I.}, title = {Planetary boundary layer evolution over the Amazon rain forest in episodes of deep moist convection at ATTO}, journal = {Atmospheric Chemistry and Physics Discussions.}, year = {2019}, doi = {https://doi.org/10.5194/acp-2019-373} } |
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Oliveira, V.R., Souza, C., Manzi, A., Alvalá, A.O., R.C.S., S., L.D.A., L. and M.M.V.B.R., M. | Fluxos Turbulentos de Energia sobre o Pantanal Sul MatoGrossense [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 371-377 |
article | |
BibTeX:
@article{oliveira_fluxos_2006, author = {Oliveira, Von Randow, C., Souza, A., Manzi, A.O., Alvalá, R.C.S., Sá, L.D.A., Leitão, M.M.V.B.R., M.B.L.}, title = {Fluxos Turbulentos de Energia sobre o Pantanal Sul MatoGrossense}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {371--377} } |
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Oliveira, S., A.J.B., M., Alvalá, A.O., R.C.S., C., Moura, M.F. and M.S.B., M. | Trocas de energia e fluxo de carbono entre a vegetação de caatinga e atmosfera no nordeste brasileiro [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 378-386 |
article | |
BibTeX:
@article{oliveira_trocas_2006, author = {Oliveira, Santos, A.J.B., Manzi, A.O., Alvalá, R.C.S., Correia, M.F., Moura, M.S.B., M.B.L.}, title = {Trocas de energia e fluxo de carbono entre a vegetação de caatinga e atmosfera no nordeste brasileiro}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {378--386} } |
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Oliveira, C., R.F.S., S., Costa, F.A., A.C. L., B. and L.L., A.P. | Precipitação efetiva e interceptação em Caxiuanã, na Amazônia Oriental [BibTeX] |
2008 | Acta Amazonica Vol. 38(4), pp. 723 - 732 |
article | |
BibTeX:
@article{oliveira_precipitacao_2008, author = {Oliveira, Costa, R.F.S., Sousa, F.A., Costa, A.C. L., Braga, A.P., L.L.}, title = {Precipitação efetiva e interceptação em Caxiuanã, na Amazônia Oriental}, journal = {Acta Amazonica}, year = {2008}, volume = {38}, number = {4}, pages = {723 -- 732} } |
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Oliveira, C., Costa, R.F., A.C.L., S., F.A.S., B. and L.L., A.P. | Modelagem da Interceptação na Floresta Nacional de Caxiuanã, no Leste da Amazônia [BibTeX] |
2008 | Revista Brasileira de Meteorologia Vol. 23(3), pp. 318-326 |
article | |
BibTeX:
@article{oliveira_modelagem_2008, author = {Oliveira, Costa, R.F., Costa, A.C.L., Sousa, F.A.S., Braga, A.P., L.L.}, title = {Modelagem da Interceptação na Floresta Nacional de Caxiuanã, no Leste da Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2008}, volume = {23}, number = {3}, pages = {318--326} } |
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Oliveira Junior, R.C.d., Keller, M.M., Ramos, J.F.d.F., Beldini, T.P., Crill, P.M., Camargo, P.B.d. and Haren, J.v. | Chemical analysis of rainfall and throughfall in the Tapajós National Forest, Belterra, Pará, Brazil [BibTeX] |
2015 | Revista Ambiente & Água Vol. 10(2), pp. 263 |
article | DOI |
BibTeX:
@article{oliveira_junior_chemical_2015, author = {Oliveira Junior, R. C. de and Keller, M. M. and Ramos, J. F. da F. and Beldini, T. P. and Crill, P. M.; and Camargo, P. B. de and Haren, J. van.}, title = {Chemical analysis of rainfall and throughfall in the Tapajós National Forest, Belterra, Pará, Brazil}, journal = {Revista Ambiente & Água}, year = {2015}, volume = {10}, number = {2}, pages = {263}, note = {Section: 285}, doi = {https://doi.org/10.4136/ambi-agua.1552} } |
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Oliveira Junior, R.C., Keller, M., Crill, P., Beldini, T., Haren, J.v. and Camargo, P. | Trace gas fluxes from intensively managed rice and soybean fields across three growing seasons in the Brazilian Amazon [BibTeX] |
2015 | African Journal of Agricultural Research Vol. 10(39), pp. 2 |
article | |
BibTeX:
@article{oliveira_junior_trace_2015, author = {Oliveira Junior, R. C. and Keller, M. and Crill, P. and Beldini, T. and Haren, J. van and Camargo, P.}, title = {Trace gas fluxes from intensively managed rice and soybean fields across three growing seasons in the Brazilian Amazon}, journal = {African Journal of Agricultural Research}, year = {2015}, volume = {10}, number = {39}, pages = {2} } |
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Oliveira, I., Campos, M., Freitas, L. and Soares, M. | Caracterização de solos sob diferentes usos na região sul do Amazonas [BibTeX] |
2015 | Acta Amazonica Vol. 45, pp. 1-12 |
article | |
BibTeX:
@article{oliveira_caracterizacao_2015, author = {Oliveira, I.A. and Campos, M.C.C. and Freitas, L. and Soares, M.D.R.}, title = {Caracterização de solos sob diferentes usos na região sul do Amazonas}, journal = {Acta Amazonica}, year = {2015}, volume = {45}, pages = {1--12} } |
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Oliveira, G.d. and Moraes, E.C. | Validação do balanço de radiação obtido a partir de dados MODIS/TERRA na Amazônia com medidas de superfície do LBA [BibTeX] |
2013 | Acta Amazonica Vol. 43(3), pp. 353 - 364 |
article | |
BibTeX:
@article{oliveira_validacao_2013, author = {Oliveira, Gabriel de and Moraes, Elisabete Caria}, title = {Validação do balanço de radiação obtido a partir de dados MODIS/TERRA na Amazônia com medidas de superfície do LBA}, journal = {Acta Amazonica}, year = {2013}, volume = {43}, number = {3}, pages = {353 -- 364} } |
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Oliveira, E.A.d., Marimon, B.S., Feldpausch, T.R., Colli, G.R., Marimon-Junior, B.H., Lloyd, J., Lenza, E., Maracahipes, L., Oliveira-Santos, C. and Phillips, O.L. | Diversity, abundance and distribution of lianas of the Cerrado-Amazonian forest transition, Brazil [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 231-240 |
article | |
BibTeX:
@article{oliveira_diversity_2014, author = {Oliveira, Edmar Almeida de and Marimon, Beatriz Schwantes and Feldpausch, Ted R. and Colli, Guarino Rinaldi and Marimon-Junior, Ben Hur and Lloyd, Jon and Lenza, Eddie and Maracahipes, Leandro and Oliveira-Santos, Claudinei and Phillips, Oliver L.}, title = {Diversity, abundance and distribution of lianas of the Cerrado-Amazonian forest transition, Brazil}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {231--240} } |
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Oliveira, I., P. Artaxo, E., P.H.N. Saldiva, W.L.J. and S. Hacon., B.F.A. | Risk assessment of PM2.5 children residents in the Brazilian Amazon region with biofuel production [BibTeX] |
2012 | Environmental Health, pp. 11:64 | article | DOI |
BibTeX:
@article{oliveira_risk_2012, author = {Oliveira, Ignotti, E., P. Artaxo, P.H.N. Saldiva, W. L. Junger, S. Hacon., B. F. A}, title = {Risk assessment of PM2.5 children residents in the Brazilian Amazon region with biofuel production}, journal = {Environmental Health}, year = {2012}, pages = {11:64}, doi = {https://doi.org/10.1186/1476-069X-11-64} } |
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Oliveira, B.C.S., Araújo, A.C.d., Dias Pinto, C.A., Souza, C.M.A., Santiago, A.V. and Trindade, I.A. | Caracterização da variação sazonal do CO2 atmosférico em sistema iLPF no leste da Amazônia [BibTeX] |
2018 | Ciência e Natura Vol. 40, pp. 181-186 |
article | |
BibTeX:
@article{oliveira_caracterizacao_2018, author = {Oliveira, B. C. S. and Araújo, A. C. de and Dias Pinto, C. A. and Souza, C. M. A. and Santiago, A. V. and Trindade, I. A.}, title = {Caracterização da variação sazonal do CO2 atmosférico em sistema iLPF no leste da Amazônia}, journal = {Ciência e Natura}, year = {2018}, volume = {40}, pages = {181--186} } |
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Oliveira, B., Ignotti, E., Hacon, S., Rodrigues, P. and Artaxo, P. | Quantification of Exposure by PM2.5 From the Biomass Burning in the Brazilian Amazon: Estimative of Potential Dose [BibTeX] |
2011 | Epidemiology Vol. 22(1), pp. S211 |
article | DOI URL |
BibTeX:
@article{oliveira_quantification_2011, author = {Oliveira, Beatriz and Ignotti, Eliane and Hacon, Sandra and Rodrigues, Poliany and Artaxo, Paulo}, title = {Quantification of Exposure by PM2.5 From the Biomass Burning in the Brazilian Amazon: Estimative of Potential Dose}, journal = {Epidemiology}, year = {2011}, volume = {22}, number = {1}, pages = {S211}, url = {://WOS:000285400800640}, doi = {https://doi.org/10.1097/01.ede.0000392332.79764.04} } |
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Oliveira, B., Ignotti, E., Hacon, S. and Artaxo, P. | Comparison of Health Effects From Exposure to Air Pollution Derived From Combustion of Fossil Fuels and Biomass Burning in Brazil [BibTeX] |
2011 | Epidemiology Vol. 22(1), pp. S194-S195 |
article | DOI URL |
BibTeX:
@article{oliveira_comparison_2011, author = {Oliveira, Beatriz and Ignotti, Eliane and Hacon, Sandra and Artaxo, Paulo}, title = {Comparison of Health Effects From Exposure to Air Pollution Derived From Combustion of Fossil Fuels and Biomass Burning in Brazil}, journal = {Epidemiology}, year = {2011}, volume = {22}, number = {1}, pages = {S194--S195}, url = {://WOS:000285400800586}, doi = {https://doi.org/10.1097/01.ede.0000392278.97003.76} } |
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Oliveira, A., Ramos, I.L., M.B.P., N., Couto, A.D., Sahdo, L.B. and A.N., R.M. | Composição e diversidade florístico-estrutural de um hectare de floresta densa de terra firme na Amazônia Central, Amazonas, Brasil [BibTeX] |
2008 | Acta Amazonica Vol. 38(4), pp. 627 - 642 |
article | |
BibTeX:
@article{oliveira_composicao_2008, author = {Oliveira, Amaral, I.L., Ramos, M.B.P., Nobre, A.D., Couto, L.B., Sahdo, R.M., A.N.}, title = {Composição e diversidade florístico-estrutural de um hectare de floresta densa de terra firme na Amazônia Central, Amazonas, Brasil}, journal = {Acta Amazonica}, year = {2008}, volume = {38}, number = {4}, pages = {627 -- 642} } |
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Oliveira, A. and A.N., I.L. | Aspectos florístico, fitossociológico e ecológico de um sub-bosque de terra firme na Amazônia Central, Amazonas, Brasil [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 1-16 |
article | |
BibTeX:
@article{oliveira_aspectos_2005, author = {Oliveira, Amaral, I.L., A.N.}, title = {Aspectos florístico, fitossociológico e ecológico de um sub-bosque de terra firme na Amazônia Central, Amazonas, Brasil}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {1--16} } |
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Oliveira, A. and A.N., I.L. | Florística e fitossociologia de uma floresta de vertente na Amazonia Central, Amazonas, Brasil [BibTeX] |
2004 | Acta Amazonica Vol. 34, pp. 21-34 |
article | |
BibTeX:
@article{oliveira_floristica_2004, author = {Oliveira, Amaral, I.L., A.N.}, title = {Florística e fitossociologia de uma floresta de vertente na Amazonia Central, Amazonas, Brasil}, journal = {Acta Amazonica}, year = {2004}, volume = {34}, pages = {21--34} } |
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Oliveira, A.B., da Costa, A.C.L., Silva, V.P.R., Dias J., L., Patriota, M.R.A. and Rodrigues, C.C.F. | Estudo da variabilidade da temperatura e umidade do solo na área experimental do projeto Esecaflor - Caxiuanã - LBA [BibTeX] |
2018 | Ciência e Natura Vol. 40, pp. 168 |
article | |
BibTeX:
@article{oliveira_estudo_2018, author = {Oliveira, A. B.. and da Costa, A. C. L. and Silva, V. P. R.. and L., Dias J. and Patriota, M. R. A. and Rodrigues, C. C. F.}, title = {Estudo da variabilidade da temperatura e umidade do solo na área experimental do projeto Esecaflor - Caxiuanã - LBA}, journal = {Ciência e Natura}, year = {2018}, volume = {40}, pages = {168} } |
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Olander, L., Bustamante, M., Asner, G.P., Telles, E., Prado, Z. and Camargo, P. | Surface soil changes following selective logging in an eastern amazon forest | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: In the Brazilian Amazon, selective logging is second only to forest conversion in its extent. Conversion to pasture or agriculture tends to reduce soil nutrients and site productivity over time unless fertilizers are added. Logging removes nutrients in bole wood, enough that repeated logging could deplete essential nutrients over time. After a single logging event, nutrient losses are likely to be too small to observe in the large soil nutrient pools, but disturbances associated with logging also alter soil properties. Selective logging, particularly reduced- impact logging, results in consistent patterns of disturbance that may be associated with particular changes in soil properties. Soil bulk density, pH, carbon ( C), nitrogen ( N), phosphorus ( P), calcium ( Ca), magnesium ( Mg), potassium ( K), iron ( Fe), aluminum (Al), delta(13)C, delta(15)N, and P fractionations were measured on the soils of four different types of logging-related disturbances: roads, decks, skids, and treefall gaps. Litter biomass and percent bare ground were also determined in these areas. To evaluate the importance of fresh foliage inputs from downed tree crowns in treefall gaps, foliar nutrients for mature forest trees were also determined and compared to that of fresh litterfall. The immediate impacts of logging on soil properties and how these might link to the longer- term estimated nutrient losses and the observed changes in soils were studied. In the most disturbed areas, roads and decks, the authors found litter biomass removed and reduced soil C, N, P, particularly organic P, and delta(13)C. Soils were compacted and often experienced reducing conditions in the deck areas, resulting in higher pH, Ca, and Mg. No increases in soil nutrients were observed in the treefall gaps despite the flush of nutrient- rich fresh foliage in the tree crown that is left behind after the bole wood is removed. Observed nutrient losses are most likely caused by displacement of the litter layer. Increases in soil pH, Ca, and Mg occur in areas with reducing conditions ( decks and roads) and may result from Fe reduction, freeing exchange sites that can then retain these cations. Calculations suggest that nutrient inputs from crown foliage in treefall gaps are probably too small to detect against the background level of nutrients in the top soils. The logging disturbances with the greatest spatial extent, skids and gaps, have the smallest immediate effect on soil nutrients, while those with the smallest spatial extent, roads and decks, have the largest impact. The changes observed 3 - 6 months after logging were similar to those measured 16 yr after logging, suggesting some interesting linkages between the mechanisms causing the immediate change and those maintaining these changes over time. The direct impacts on soil properties appear less important than the loss of nutrients in bole wood in determining the sustainability of selective logging. Medium- to- low intensity selective logging with a sufficiently long cutting cycle may be sustainable in these forests. | |||||
BibTeX:
@article{olander_surface_2005, author = {Olander, L.P. and Bustamante, M.M. and Asner, G. P. and Telles, E. and Prado, Z. and Camargo, P.B.}, title = {Surface soil changes following selective logging in an eastern amazon forest}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241212100001} } |
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Okin, G.S., Mahowald, N., Chadwick, O.A. and Artaxo, P. | Impact of desert dust on the biogeochemistry of phosphorus in terrestrial ecosystems | 2004 | Global Biogeochemical Cycles Vol. 18(2) |
article | DOI URL |
Abstract: [1] Leaching, biomass removal, and partitioning of phosphorus ( P) into reservoirs not available to plants can limit the long-term productivity of terrestrial ecosystems. We evaluate the importance of atmospheric P inputs to the world's soils by estimating the total soil P turnover time with respect to dustborne P additions. Estimated turnover times range from similar to 10(4) to similar to 10(7) years. Our estimates provide a unique perspective on the importance and patterns of aeolian deposition to terrestrial landscapes. Dust source regions are areas of intense soil P cycling on large scales, but are too water-limited for this rapid cycling to have a major influence on ecosystem dynamics. By contrast, semiarid desert margins receive significant aeolian P from neighboring deserts and are likely influenced by dustborne P additions for the long-term maintenance of productivity. This is particularly true for the semiarid steppes of Africa and Eurasia. The prevalence of large dust sources in Africa and Eurasia indicates that these areas may generally be more influenced by dustborne P additions than soils in the Americas. Significant western hemisphere exceptions to this pattern occur on very old landscapes, such as the forests of the southeastern United States and the Amazon Basin. The Amazon Basin is highly dependent on aeolian deposition for the maintenance of long-term productivity. Dust deposition to terrestrial environments has not been constant with time. Variability in past P deposition related to geologically recent climate change may provide the strongest controls on present and future soil P in the Amazon and elsewhere. | |||||
BibTeX:
@article{okin_impact_2004, author = {Okin, G. S. and Mahowald, N. and Chadwick, O. A. and Artaxo, P.}, title = {Impact of desert dust on the biogeochemistry of phosphorus in terrestrial ecosystems}, journal = {Global Biogeochemical Cycles}, year = {2004}, volume = {18}, number = {2}, url = {://WOS:000221086100001}, doi = {https://doi.org/10.1029/2003gb002145} } |
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Nunes, H.G.G.C., Barreto, P.N., Silva, R.B.C.d., Rodrigues, R.S. and Sá, L.D.A. | Variabilidade da Skewness da temperatura potencial equivalente na Floresta Nacional de Caxiuanã, PA [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 165-168 |
article | |
BibTeX:
@article{nunes_variabilidade_2009, author = {Nunes, Hildo G. G. C. and Barreto, Priscilla N. and Silva, Rommel B. C. da and Rodrigues, Ronaldo S. and Sá, Leonardo D. A.}, title = {Variabilidade da Skewness da temperatura potencial equivalente na Floresta Nacional de Caxiuanã, PA}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {165--168} } |
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Nunes, E., Costa, M., Malhado, A., Dias, L., Vieira, S., Pinto, L. and Ladle, R. | Monitoring carbon assimilation in South America's tropical forests: Model specifi cation and application to the Amazonian droughts of 2005 and 2010 [BibTeX] |
2012 | Remote Sensing of Environment Vol. 117, pp. 449-46 |
article | |
BibTeX:
@article{nunes_monitoring_2012, author = {Nunes, E.L. and Costa, M.H. and Malhado, A.C.M. and Dias, L.C.P. and Vieira, S.A. and Pinto, L.B. and Ladle, R.J.}, title = {Monitoring carbon assimilation in South America's tropical forests: Model specifi cation and application to the Amazonian droughts of 2005 and 2010}, journal = {Remote Sensing of Environment}, year = {2012}, volume = {117}, pages = {449--46} } |
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Nunes Carvalho, J.L., Pelegrino Cerri, C.E., Feigl, B.J., Piccolo, M.d.C., Godinho, V.d.P., Herpin, U. and Cerri, C.C. | Conversion of cerrado into agricultural land in the south-western amazon: carbon stocks and soil fertility | 2009 | Scientia Agricola Vol. 66(2), pp. 233-241 |
article | URL |
Abstract: Land use change and land management practices can modify soil carbon (C) dynamics and soil fertility. This study evaluated the effect of tillage systems (no-tillage - NT and conventional tillage - CT) on soil C and nutrient stocks in an Oxisol from an Amazonian cerrado following land use change. The study also identified relationships between these stocks and other soil attributes. Carbon, P, K, Ca and Mg stocks, adjusted to the equivalent soil mass in the cerrado (CE), were higher under NT. After adoption of all but one of the NT treatments, C stocks were higher than they were in the other areas we considered. Correlations between C and nutrient stocks showed positive correlations with Ca and Mg under NT due to continuous liming, higher crop residue inputs and lack of soil disturbance, associated with positive correlations with cation exchange capacity (CEC), base saturation and pH. The positive correlation (r = 0.91, p textless 0.05) between C stocks and CEC in the CE indicates the important contribution of soil organic matter (SOM) to CEC in tropical soils, although the exchange sites are under natural conditions - mainly occupied by H and Al. Phosphorus and K stocks showed positive correlations (0.81 and 0.82, respectively) with C stocks in the CE, indicating the direct relationship of P and K with SOM in natural ecosystems. The high spatial variability of P and K fertilizer application may be obscuring these soil nutrient stocks. In this study, the main source of P and K was fertilizer rather than SOM. | |||||
BibTeX:
@article{nunes_carvalho_conversion_2009, author = {Nunes Carvalho, Joao Luis and Pelegrino Cerri, Carlos Eduardo and Feigl, Brigitte Josefine and Piccolo, Marisa de Cassia and Godinho, Vicente de Paula and Herpin, Uwe and Cerri, Carlos Clemente}, title = {Conversion of cerrado into agricultural land in the south-western amazon: carbon stocks and soil fertility}, journal = {Scientia Agricola}, year = {2009}, volume = {66}, number = {2}, pages = {233--241}, url = {://WOS:000265051600013} } |
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Nunes, C.A., Berenguer, E., França, F., Ferreira, J., Lees, A.C., Louzada, J., Sayer, E.J., Solar, R., Smith, C.C., Aragão, L.E.O.C., Braga, D.d.L., de Camargo, P.B., Cerri, C.E.P., de Oliveira, R.C., Durigan, M., Moura, N., Oliveira, V.H.F., Ribas, C., Vaz-de-Mello, F., Vieira, I., Zanetti, R. and Barlow, J. | Linking land-use and land-cover transitions to their ecological impact in the Amazon | 2022 | Proceedings of the National Academy of Sciences Vol. 119(27), pp. e2202310119 |
article | DOI URL |
Abstract: Human activities pose a major threat to tropical forest biodiversity and ecosystem services. Although the impacts of deforestation are well studied, multiple land-use and land-cover transitions (LULCTs) occur in tropical landscapes, and we do not know how LULCTs differ in their rates or impacts on key ecosystem components. Here, we quantified the impacts of 18 LULCTs on three ecosystem components (biodiversity, carbon, and soil), based on 18 variables collected from 310 sites in the Brazilian Amazon. Across all LULCTs, biodiversity was the most affected ecosystem component, followed by carbon stocks, but the magnitude of change differed widely among LULCTs and individual variables. Forest clearance for pasture was the most prevalent and high-impact transition, but we also identified other LULCTs with high impact but lower prevalence (e.g., forest to agriculture). Our study demonstrates the importance of considering multiple ecosystem components and LULCTs to understand the consequences of human activities in tropical landscapes. | |||||
BibTeX:
@article{nunes_linking_2022, author = {Nunes, Cássio Alencar and Berenguer, Erika and França, Filipe and Ferreira, Joice and Lees, Alexander C. and Louzada, Julio and Sayer, Emma J. and Solar, Ricardo and Smith, Charlotte C. and Aragão, Luiz E. O. C. and Braga, Danielle de Lima and de Camargo, Plinio Barbosa and Cerri, Carlos Eduardo Pellegrino and de Oliveira, Raimundo Cosme and Durigan, Mariana and Moura, Nárgila and Oliveira, Victor Hugo Fonseca and Ribas, Carla and Vaz-de-Mello, Fernando and Vieira, Ima and Zanetti, Ronald and Barlow, Jos}, title = {Linking land-use and land-cover transitions to their ecological impact in the Amazon}, journal = {Proceedings of the National Academy of Sciences}, year = {2022}, volume = {119}, number = {27}, pages = {e2202310119}, url = {https://www.pnas.org/doi/abs/10.1073/pnas.2202310119}, doi = {https://doi.org/10.1073/pnas.2202310119} } |
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Nunes, C.A., Barlow, J., França, F., Berenguer, E., Solar, R.R.C., Louzada, J., Leitão, R.P., Maia, L.F., Oliveira, V.H.F., Braga, R.F., Vaz-de-Mello, F.Z. and Sayer, E.J. | Functional redundancy of Amazonian dung beetles confers community-level resistance to primary forest disturbance | 2021 | Biotropica Vol. 53(6), pp. 1510-1521 |
article | DOI URL |
Abstract: Abstract Tropical forest biodiversity is being threatened by human activities, and species losses during forest disturbance can compromise important ecosystem functions and services. We assessed how species losses due to tropical forest disturbance affect community functional structure, using Amazonian dung beetles as a model group. We collected empirical data from 106 forest transects and used simulated extinction scenarios to determine how species loss influences community structure at regional and local scales. Although functional and taxonomic community metrics were largely unaffected by primary forest disturbance, they differed markedly between primary and secondary forests. However, our extinction scenarios demonstrated scale-dependence of species losses, whereby functional structure only eroded with species extinction at the local scale. Hence, we extend the spatial insurance hypothesis by demonstrating that landscape-scale functional redundancy offsets the impact of local species losses and confers community-level resistance to primary forest disturbance. Abstract in portuguese is available with online material. | |||||
BibTeX:
@article{nunes_functional_2021, author = {Nunes, Cássio Alencar and Barlow, Jos and França, Filipe and Berenguer, Erika and Solar, Ricardo R. C. and Louzada, Julio and Leitão, Rafael P. and Maia, Laís F. and Oliveira, Victor H. F. and Braga, Rodrigo Fagundes and Vaz-de-Mello, Fernando Z. and Sayer, Emma J.}, title = {Functional redundancy of Amazonian dung beetles confers community-level resistance to primary forest disturbance}, journal = {Biotropica}, year = {2021}, volume = {53}, number = {6}, pages = {1510--1521}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/btp.12998}, doi = {https://doi.org/10.1111/btp.12998} } |
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Numata, I., Soares, J.V., Roberts, D.A., Leonidas, F.C., Chadwick, O.A. and Batista, G.T. | Relationships among soil fertility dynamics and remotely sensed measures across pasture chronosequences in Rondonia, Brazil | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 446-455 |
article | DOI URL |
Abstract: This study analyzed the relationships between soil fertility and remotely sensed measures over three pasture chronosequence sites in the state of Rondonia, in the western Brazilian Amazon region. Remotely sensed measures included shade, nonphotosynthetic vegetation (NPV), green vegetation (GV) and soil (derived from spectral mixture analysis), and the normalized difference vegetation index (NDVI). These were correlated against soil fertility parameters such as phosphorus, potassium, calcium, and base saturation. In temporal analysis, it was observed that NPV dominated the spectral responses of pasture canopies and tended to increase with pasture age as well. The increase of NPV appeared to be related to the decline of soil fertility, but soil texture variation also played a role. In the correlation analysis, soil P, known as the most limiting nutrient for pasture productivity, showed the highest correlation with remotely sensed measures, followed by soil K and base saturation. However, this result was not observed at the sites where nutrient availability was very low. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{numata_relationships_2003, author = {Numata, I. and Soares, J. V. and Roberts, D. A. and Leonidas, F. C. and Chadwick, O. A. and Batista, G. T.}, title = {Relationships among soil fertility dynamics and remotely sensed measures across pasture chronosequences in Rondonia, Brazil}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {446--455}, url = {://WOS:000186827400005}, doi = {https://doi.org/10.1016/j.rse.2002.07.001} } |
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Numata, I., Roberts, D.A., Sawada, Y., Chadwick, O.A., Schimel, J.P. and Soares, J.V. | Regional characterization of pasture changes through time and space in Rondonia, Brazil | 2007 | Earth Interactions Vol. 11 |
article | URL |
Abstract: Although pasture degradation has been a regional concern in Amazonian ecosystems, our ability to characterize and monitor pasture degradation under different environmental and human-related conditions is still limited. Regional analysis of pasture dynamic patterns was conducted using high-frequency temporal satellite data and ancillary data to better understand pasture degradation under varied soil, environmental, and pasture management conditions in the state of Rondonia, Brazil. The 10-day normalized difference vegetation index (NDVI) composite derived from Moderate Resolution Imaging Spectroradiometer ( MODIS) 250-m resolution was used to characterize different grass phenological patterns for 32 counties in Rondonia between 2001 and 2003. Six pasture greenness classes showed that high greenness pasture classes dominated in young pastures, while low greenness pasture classes were least common. As pastures aged, the proportion of high greenness pasture classes decreased and the proportion of low greenness pastures increased, indicating a decrease in forage productivity over time in Rondonia. The magnitude of productivity decline depended on environmental constraints and land use systems. To refine this analysis, trajectories of pasture change were determined using spectral mixture analysis applied to Landsat time series data from 1988 to 2001 with the focus on two counties that show contrasting patterns of potential of grass production: Pimenteira, representing the "degraded" pasture category, and Governador Jorge Teixeira, as the "productive" pasture category. The results revealed a clear pasture degradation pattern in Pimenteira, related to low soil fertility and dry climate conditions, while Governador Jorge Teixeira, with better soil fertility and intermediate precipitation, did not show signs of pasture degradation through time. | |||||
BibTeX:
@article{numata_regional_2007, author = {Numata, Izaya and Roberts, Dar A. and Sawada, Yoshito and Chadwick, Oliver A. and Schimel, Joshua P. and Soares, Joao V.}, title = {Regional characterization of pasture changes through time and space in Rondonia, Brazil}, journal = {Earth Interactions}, year = {2007}, volume = {11}, url = {://WOS:000249563100001} } |
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Numata, I., Roberts, D.A., Chadwick, O.A., Schimel, J.P., Galvao, L.S. and Soares, J.V. | Evaluation of hyperspectral data for pasture estimate in the Brazilian Amazon using field and imaging spectrometers | 2008 | Remote Sensing of Environment Vol. 112(4), pp. 1569-1583 |
article | DOI URL |
Abstract: We used two hyperspectral sensors at two different scales to test their potential to estimate biophysical properties of grazed pastures in Rondonia in the Brazilian Amazon. Using a field spectrometer, ten remotely sensed measurements (i.e., two vegetation indices, four fractions of spectral mixture analysis, and four spectral absorption features) were generated for two grass species, Brachiaria brizantha and Brachiaria decumbens. These measures were compared to above ground biomass, live and senesced biomass, and grass canopy water content. The sample size was 69 samples for field grass biophysical data and grass canopy reflectance. Water absorption measures between 1 100 and 1250 nm had the highest correlations with above ground biomass, live biomass and canopy water content, while ligno-cellulose absorption measures between 2045 and 2218 nm were the best for estimating senesced biomass. These results suggest possible improvements on estimating grass measures using spectral absorption features derived from hyperspectral sensors. However, relationships were highly influenced by grass species architecture. B. decumbens, a more homogeneous, low growing species, had higher correlations between remotely sensed measures and biomass than B. brizantha, a more heterogeneous, vertically oriented species. The potential of using the Earth Observing-1 Hyperion data for pasture characterization was assessed and validated using field spectrometer and CCD camera data. Hyperion-derived NPV fraction provided better estimates of grass surface fraction compared to fractions generated from convolved ETM+/Landsat 7 data and minimized the problem of spectral ambiguity between NPV and Soil. The results suggest possible improvement of the quality of land-cover maps compared to maps made using multispectral sensors for the Amazon region. (C) 2007 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{numata_evaluation_2008, author = {Numata, Izaya and Roberts, Dar A. and Chadwick, Oliver A. and Schimel, Joshua P. and Galvao, Lenio S. and Soares, Joao V.}, title = {Evaluation of hyperspectral data for pasture estimate in the Brazilian Amazon using field and imaging spectrometers}, journal = {Remote Sensing of Environment}, year = {2008}, volume = {112}, number = {4}, pages = {1569--1583}, url = {://WOS:000254961500025}, doi = {https://doi.org/10.1016/j.rse.2007.08.014} } |
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Numata, I., Roberts, D.A., Chadwick, O.A., Schimel, J., Sampaio, F.R., Leonidas, F.C. and Soares, J.V. | Characterization of pasture biophysical properties and the impact of grazing intensity using remotely sensed data | 2007 | Remote Sensing of Environment Vol. 109(3), pp. 314-327 |
article | DOI URL |
Abstract: Remote sensing has the potential of improving our ability to map and monitor pasture degradation. Pasture degradation is one of the most important problems in the Amazon, yet the manner in which grazing intensity, edaphic conditions and land-use age impact pasture biophysical properties, and our ability to monitor them using remote sensing is poorly known. We evaluate the connection between field grass biophysical measures and remote sensing, and investigate the impact of grazing intensity on pasture biophysical measures in Rondonia, in the Brazilian Amazon. Above ground biomass, canopy water content and height were measured in different pasture sites during the dry season. Using Landsat Thematic Mapper (TM) data, four spectral vegetation indices and fractions derived from spectral mixture analysis, i.e., Non-Photosynthetic Vegetation (NPV), Green Vegetation (GV), Soil, Shade, and NPV+Soil, were calculated and compared to field grass measures. For grazed pastures under dry conditions, the Normalized Difference Infrared Index (ND115 and ND117), had higher correlations with the biophysical measures than the Normalized Difference Vegetation Index (NDVI) and the Soil-Adjusted Vegetation Index (SAVI). NPV had the highest correlations with all field measures, suggesting this fraction is a good indicator of pasture characteristics in Rondonia. Pasture height was correlated to the Shade fraction. A conceptual model was built for pasture biophysical change using three fractions, i.e., NPV, Shade and GV to characterize possible pasture degradation processes in Rondonia. Based upon field measures, grazing intensity had the most significant impact on pasture biophysical properties compared to soil order and land-use age. The impact of grazing on pastures in the dry season could be potentially measured by using remotely sensed measures such as NPV. (C) 2007 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{numata_characterization_2007, author = {Numata, Izaya and Roberts, Dar A. and Chadwick, Oliver A. and Schimel, Josh and Sampaio, Fernando R. and Leonidas, Francisco C. and Soares, Jodo V.}, title = {Characterization of pasture biophysical properties and the impact of grazing intensity using remotely sensed data}, journal = {Remote Sensing of Environment}, year = {2007}, volume = {109}, number = {3}, pages = {314--327}, url = {://WOS:000248091500005}, doi = {https://doi.org/10.1016/j.rse.2007.01.013} } |
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Numata, I., Cochrane, M.A., Roberts, D.A., Soares, J.V., Souza Jr., C.M. and Sales, M.H. | Biomass collapse and carbon emissions from forest fragmentation in the Brazilian Amazon | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115 |
article | DOI URL |
Abstract: [1] Forest fragmentation due to deforestation is one of the major causes of forest degradation in the Amazon. Biomass collapse near forest edges, especially within 100 m, alters aboveground biomass and has potentially important implications for carbon emissions in the region. This phenomenon is tightly linked to spatial and temporal dynamics of forest edges in a landscape. However, the potential biomass loss and carbon emissions from forest edges and these spatiotemporal changes have never been estimated for actual landscapes in the Amazon. We conducted a deep temporal analysis of Rondonia, southwestern Brazilian Amazonia, using six Landsat path-row scenes covering the 1985-2008 time period to estimate annual biomass loss and associated carbon emissions within 100 m of forest edges. Annual edge biomass loss averaged 9.1% of the biomass loss from deforestation during the study period, whereas average annual edge-related carbon emissions from biomass loss were 6.0% of deforestation-derived carbon emissions. However, because many edges were subsequently deforested during the 24 year study period, actual unaccounted for edge-related carbon emissions during the 1985-2008 period, calculated from edges of all ages extant on the landscape in 2008, amounted to 3.6% of that attributed to all deforestation-derived carbon fluxes for this time interval. Biomass loss and carbon emissions are highly influenced by the extent and age of edge-affected forests. Large annual contributions of biomass loss and carbon emissions were found from active deforestation regions with young edges, whereas regions dominated by older edges had lower biomass loss and carbon emissions from edges. | |||||
BibTeX:
@article{numata_biomass_2010, author = {Numata, Izaya and Cochrane, Mark A. and Roberts, Dar A. and Soares, Joao V. and Souza, Jr., Carlos M. and Sales, Marcio H.}, title = {Biomass collapse and carbon emissions from forest fragmentation in the Brazilian Amazon}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, url = {://WOS:000282322600001 http://www.agu.org/pubs/crossref/2010/2009JG001198.shtml}, doi = {https://doi.org/10.1029/2009jg001198} } |
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Numata, I., Cochrane, M.A., Roberts, D.A. and Soares, J.V. | Determining dynamics of spatial and temporal structures of forest edges in South Western Amazonia | 2009 | Forest Ecology and Management Vol. 258(11), pp. 2547-2555 |
article | DOI URL |
Abstract: Forest edges in the Amazon are very dynamic with ongoing deforestation adding new edges as older edges are eroded. Rates of edge erosion and the composition of edge ages, together with distance from edges, are very important factors in determining the magnitude of forest degradation such as biomass collapse and carbon flux. However, we lack an understanding of how these factors change through time and over the different stages of deforestation. In this study, we quantify the spatial and temporal structures of forest edge in Rondonia, southwestern Amazon, by analyses of 22 years of annual satellite imagery, and discuss the implications for biomass dynamics and forest degradation caused by edges. Our results from three different stages of deforestation (early, intermediate and advanced) reveal that more than 50% of forest edges were eliminated in the first four years after edge creation and only 20% of edges survived more than 10 years. High edge erosion rates in the first year imply that many edges disappear before going through the process of edge-induced biomass collapse. At the early stage of deforestation, young forest edges are predominant, while at the advanced deforestation stage more than 50% of total edges are textgreater10 years old. Rapid erosion is more prevalent in early stages, when young forest edges dominate the landscape. Edge-related biomass collapse is substantially more advanced in heavily deforested regions where forests are mostly surrounded mostly by older edges, but relatively few edges remain at this point. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{numata_determining_2009, author = {Numata, Izaya and Cochrane, Mark A. and Roberts, Dar A. and Soares, Joao V.}, title = {Determining dynamics of spatial and temporal structures of forest edges in South Western Amazonia}, journal = {Forest Ecology and Management}, year = {2009}, volume = {258}, number = {11}, pages = {2547--2555}, url = {://WOS:000271708500022}, doi = {https://doi.org/10.1016/j.foreco.2009.09.011} } |
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Numata, I., Cochrane, M.A. and Galvao, L.S. | Analyzing the Impacts of Frequency and Severity of Forest Fire on the Recovery of Disturbed Forest using Landsat Time Series and EO-1 Hyperion in the Southern Brazilian Amazon | 2011 | Earth Interactions Vol. 15(13) |
article | DOI URL |
Abstract: Estimation of fire impacts and forest recovery using remote sensing is difficult because of the heterogeneity of fire history (frequency, severity, and time since last fire) across burned forest landscapes. The authors analyzed impacts of fire frequency and severity within recovering forests in the Amazon region using remote sensing. A multispectral Landsat time series dataset was used to reconstruct the fire history from 1990 to 2002 in a portion of Mato Grosso, Brazil. Five narrowband vegetation indices were then calculated from a hyperspectral Earth Observing One (EO-1) Hyperion image for spectral analysis of physiological characteristics of fire-disturbed forests and their recovery. A total of 30% of the forests burned during the study period, with 72% burned once, 24% burned twice, and less than 4% burned three times. In terms of severity, 70% of burned forest was lightly burned, 21.1% was moderately burned, and 9.1% was severely burned. Analyses of spectral indices [normalized difference vegetation index (NDVI), carotenoid reflectance index (CRI), and photochemical reflectance index (PRI)] showed that those related to canopy greenness and pigment contents can discriminate between burned forests and undisturbed forest for the first 3 years after forest fire, whereas the effectiveness of canopy water content indices [normalized difference water index (NDWI) and normalized difference infrared index (NDII)] varied from 1 to 3 years, depending on the fire severity. Despite the relatively low signal-to-noise ratios of Hyperion imagery, we show that narrowband-derived indices provide useful information for monitoring degraded forests beyond what is currently possible with Landsat. This illustrates the great potential for environmental monitoring using satellite-borne hyperspectral sensors, such as the Hyperspectral Infrared Imager (HyspIRI), which have better signal-to-noise ratios. | |||||
BibTeX:
@article{numata_analyzing_2011, author = {Numata, Izaya and Cochrane, Mark A. and Galvao, Lenio S.}, title = {Analyzing the Impacts of Frequency and Severity of Forest Fire on the Recovery of Disturbed Forest using Landsat Time Series and EO-1 Hyperion in the Southern Brazilian Amazon}, journal = {Earth Interactions}, year = {2011}, volume = {15}, number = {13}, url = {://WOS:000291148500001 http://journals.ametsoc.org/doi/abs/10.1175/2010EI372.1}, doi = {https://doi.org/10.1175/2010ei372.1} } |
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Numata, I., Chadwick, O.A., Roberts, D.A., Schimel, J.P., Sampaio, F.F., Leonidas, F.C. and Soares, J.V. | Temporal nutrient variation in soil and vegetation of post-forest pastures as a function of soil order, pasture age, and management, Rondonia, Brazil | 2007 | Agriculture Ecosystems & Environment Vol. 118(1-4), pp. 159-172 |
article | DOI URL |
Abstract: Understanding pasture degradation processes is key for sustainable development in the Amazon region. Pasture degradation can be indexed by pasture nutritional status, which is impacted by environmental and human related factors. Most studies of the biogeochernistry of Amazonian pastures have been restricted to highly acidic soils with little focus on how management affects pasture biogeochemistry. We investigated soil physical and chemical properties and grass nutrients under different edaphic conditions and management practices in Rond (o) over cap nia state, in the southwestern Amazon region. Our objectives were to analyze the impacts of soil order, pasture age, and pasture management on soil fertility, bulk density and plant nutrients, in order to understand sustainability needs for the future of this region. We sampled 17 study sites on Oxisols, Ultisols, and Alfisols. The pasture age classes we used consisted of 6-10, 11-15, and textgreater 16 years including forest as the control. We also evaluated the impact of beef and dairy management strategies on pastures installed on Ultisols. Pastures on Alfisols showed the highest soil P, Ca, and base saturation, properties that decreased gradually after 5 years of pasture installation. In contrast, pastures on Oxisols showed low and stable levels of nutrients regardless of age. Foliar nutrient concentrations appear to be influenced by edaphic conditions. Soil P and foliar P concentration were highly correlated. In general, pasture age was a poor indicator of soil fertility and foliar chemistry because of high variability among pastures belonging to the same soil order. In terms of the impacts of pasture management, we did not observe significant differences in soil or foliar properties in pasture used for beef and dairy on Ultisols. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{numata_temporal_2007, author = {Numata, Izaya and Chadwick, Oliver A. and Roberts, Dar A. and Schimel, Joshua P. and Sampaio, Fernando F. and Leonidas, Francisco C. and Soares, Joao V.}, title = {Temporal nutrient variation in soil and vegetation of post-forest pastures as a function of soil order, pasture age, and management, Rondonia, Brazil}, journal = {Agriculture Ecosystems & Environment}, year = {2007}, volume = {118}, number = {1-4}, pages = {159--172}, url = {://WOS:000243609800015}, doi = {https://doi.org/10.1016/j.agee.2006.05.019} } |
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Novo, E., Costa, M.P.F., Mantovani, J.E. and Lima, I.B.T. | Relationship between macrophyte stand variables and radar backscatter at L and C band, Tucurui reservoir, Brazil | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1241-1260 |
article | DOI URL |
Abstract: Information on macrophyte distribution in space and time is very important for tropical reservoir management. Macrophyte stands are major sinks/sources of methane and the knowledge of their spatial and temporal variation in biomass is useful for improving the assessment of the role of reservoirs in the carbon cycle. Moreover, macrophyte stands are a driving force in insect-induced diseases such as malaria. In this paper we examine the relationship between macrophyte stand variables such as above-ground biomass, stand average height and moisture, and radar backscatter at C and L bands. The study was carried out in Tucurui reservoir, where ground data were available concurrently to JERS-1 and RADARSAT overpasses. The results showed that C band is much more sensitive to macrophyte leaf shape than L band. However, L band proved to be more sensitive to above-ground biomass and stand height. Results support the integration of L and C band images to discriminate among the three main genera found in Tucurui: Typha, Ciperacea and Eicchornia. | |||||
BibTeX:
@article{novo_relationship_2002, author = {Novo, E.M.L.N. and Costa, M. P. F. and Mantovani, J. E. and Lima, I. B. T.}, title = {Relationship between macrophyte stand variables and radar backscatter at L and C band, Tucurui reservoir, Brazil}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1241--1260}, url = {://WOS:000174661900004}, doi = {https://doi.org/10.1080/04130060110092885} } |
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Novo Ferreira, L.B.C.C.C.S.E.S.Y.H.A.P.C.R.D.H.L.M.J.Y.H.K.S.K.V.M.R.R.P.K.D.M.T.E. | Técnicas avançadas de sensoriamento remoto aplicadas ao estudo de mudanças climáticas e ao funcionamento dos ecossistemas amazônicos [BibTeX] |
2005 | Acta Amazonica Vol. 35(2), pp. 259-272 |
article | |
BibTeX:
@article{novo_tecnicas_2005, author = {Novo, Ferreira, L.G., Barbosa, C., Carvalho, C., Sano, E.E., Shimabukuro, Y., Huete, A., Potter, C.R., Roberts, D.A., Hess L.L., Melack, J.J., Yoshioka, H., Klooster, S., Kumar, V., Myneni, R., Ratana, P., Kamel, D., Miura, T., E.M.L.M.}, title = {Técnicas avançadas de sensoriamento remoto aplicadas ao estudo de mudanças climáticas e ao funcionamento dos ecossistemas amazônicos}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, number = {2}, pages = {259--272} } |
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Novo, E., Pereira, W. and Melack, J.M. | Assessing the utility of spectral band operators to reduce the influence of total suspended solids on the relationship between chlorophyll concentration and the bidirectional reflectance factor in Amazon waters | 2004 | International Journal of Remote Sensing Vol. 25(22), pp. 5105-5116 |
article | DOI URL |
Abstract: Measurements of reflectance spectra, total suspended solids (TSS), chlorophyll a+phaeophytin (CLH) and dissolved organic carbon (DOC) plus pH, Secchi disk transparency and water depth were made in lakes associated with the Amazons and Negro rivers upstream from Manaus. Reflectance spectra were acquired between 400 and 900 nm using a spectroradiometer with a nominal resolution of 3 nm. Two spectral band operators designed to detect the CHL signal in waters with high TSS concentrations were examined with the aid of linear and nonlinear regression methods. Results showed that none of the proposed operators were successful in Amazon white water systems. | |||||
BibTeX:
@article{novo_assessing_2004, author = {Novo, Emlm and Pereira, W. and Melack, J. M.}, title = {Assessing the utility of spectral band operators to reduce the influence of total suspended solids on the relationship between chlorophyll concentration and the bidirectional reflectance factor in Amazon waters}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {22}, pages = {5105--5116}, url = {://WOS:000225322000016}, doi = {https://doi.org/10.1080/01431160410001709048} } |
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Norby, R.J., De Kauwe, M.G., Domingues, T.F., Duursma, R.A., Ellsworth, D.S., Goll, D.S., Lapola, D.M., Luus, K.A., MacKenzie, A.R., Medlyn, B.E., Pavlick, R., Rammig, A., Smith, B., Thomas, R., Thonicke, K., Walker, A.P., Yang, X. and Zaehle, S. | Model-data synthesis for the next generation of forest free-air 002 enrichment (FACE) experiments [BibTeX] |
2016 | New Phytol. Vol. 209(1), pp. 17-28 |
article | DOI |
BibTeX:
@article{norby_model-data_2016, author = {Norby, R. J. and De Kauwe, M. G. and Domingues, T. F. and Duursma, R. A. and Ellsworth, D. S. and Goll, D. S. and Lapola, D. M. and Luus, K. A. and MacKenzie, A. Rob and Medlyn, B. E. and Pavlick, R. and Rammig, A. and Smith, B. and Thomas, R. and Thonicke, K. and Walker, A. P. and Yang, X. and Zaehle, S.}, title = {Model-data synthesis for the next generation of forest free-air 002 enrichment (FACE) experiments}, journal = {New Phytol.}, year = {2016}, volume = {209}, number = {1}, pages = {17--28}, doi = {https://doi.org/10.1111/nph.13593} } |
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Nolscher, A., Yañez-Serrano, A., Wolff, S., Araujo, A.C.d., Lavric, J., Kesselmeier, J. and Williams, J. | Unexpected seasonality in quantity and composition of Amazon rainforest air reactivity [BibTeX] |
2016 | Nature Comunications, pp. DOI: 10.1038/ncomms10383 O | article | DOI |
BibTeX:
@article{nolscher_unexpected_2016, author = {Nolscher, A.C. and Yañez-Serrano, A.M. and Wolff, S. and Araujo, A. Carioca de and Lavric, J.V. and Kesselmeier, J. and Williams, J.}, title = {Unexpected seasonality in quantity and composition of Amazon rainforest air reactivity}, journal = {Nature Comunications}, year = {2016}, pages = {DOI: 10.1038/ncomms10383 O}, doi = {https://doi.org/10.1038/ncomms10383} } |
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Nogueira, E.M., Nelson, B.W., Fearnside, P.M., Franca, M.B. and Alves de Oliveira, A.C. | Tree height in Brazil's 'arc of deforestation': Shorter trees in south and southwest Amazonia imply lower biomass | 2008 | Forest Ecology and Management Vol. 255(7), pp. 2963-2972 |
article | DOI URL |
Abstract: This paper estimates the difference in stand biomass due to shorter and lighter trees in southwest (SW) and southern Amazonia (SA) compared to trees in dense forests in central Amazonia (CA). Forest biomass values used to estimate carbon emissions from deforestation throughout, Brazilian Amazonia will be affected by any differences between CA forests and those in the "arc of deforestation" where clearing activity is concentrated along the southern edge of the Amazon forest. At 12 sites (in the Brazilian states of Amazonas, Acre, Mato Grosso and Para) 763 trees were felled and measurements were made of total height and of stem diameter. In CA dense forest, trees are taller at any given diameter than those in SW bamboo-dominated open, SW bamboo-free dense forest and SA open forests. Compared to CA, the three forest types in the arc of deforestation occur on more fertile soils, experience a longer dry season and/or are disturbed by climbing bamboos that cause frequent crown damage. Observed relationships between diameter and height were consistent with the argument that allometric scaling exponents vary in forests on different substrates or with different levels of natural disturbance. Using biomass equations based only on diameter, the reductions in stand biomass due to shorter tree height alone were 11.0, 6.2 and 3.6%, respectively, in the three forest types in the arc of deforestation. A prior study had shown these forest types to have less dense wood than CA dense forest. When tree height and wood density effects were considered jointly, total downward corrections to estimates of stand biomass were 39, 22 and 16%, respectively. Downward corrections to biomass in these forests were 76 Mg ha(-1) (similar to 21.5 Mg ha(-1) from the height effect alone), 65 Mg ha(-1) (18.5 Mg ha(-1) from height), and 45 Mg. ha(-1) (10.3 Mg ha(-1) from height). Hence, biomass stock and carbon emissions are overestimated when allometric relationships from dense forest are applied to SW or SA forest types. Biomass and emissions estimates in Brazil's National Communication under the United Nations Framework Convention on Climate Change require downward corrections for both wood density and tree height. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{nogueira_tree_2008, author = {Nogueira, Euler Melo and Nelson, Bruce Walker and Fearnside, Philip Martin and Franca, Mabiane Batista and Alves de Oliveira, Atila Cristina}, title = {Tree height in Brazil's 'arc of deforestation': Shorter trees in south and southwest Amazonia imply lower biomass}, journal = {Forest Ecology and Management}, year = {2008}, volume = {255}, number = {7}, pages = {2963--2972}, url = {://WOS:000256143900092}, doi = {https://doi.org/10.1016/j.foreco.2008.02.002} } |
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Nogueira, E.M., Nelson, B.W. and Fearnside, P.M. | Wood density in dense forest in central Amazonia, Brazil | 2005 | Forest Ecology and Management Vol. 208(1-3), pp. 261-286 |
article | DOI URL |
Abstract: Measurements of wood density of trees in Amazonian forests are necessary to reduce uncertainties in estimates of carbon stocks and of greenhouse-gas emissions from deforestation. Based on samples from 310 trees in 186 species or morpho-species collected near Manaus, Brazil, the present study finds that commonly used wood density estimates found in published lists by species need to be adjusted downward by 5.3%. Taking the average bole density from this study as a standard, wood density overestimations in three prior studies of the central Amazon were found to be 6%, 4% and 0%. Estimates of primary forest biomass and of gross emissions from biomass loss through deforestation will have to be reduced by similar percentages. Considering full disks with bark dried at 103 degrees C, the mean basic density at breast height in the Central Amazon dense forest was 0.704 +/- 0.117 (mean I standard deviation; n = 310; range, 0.27-0.96); at the top of the bole it was 0.647 +/- 0.093 (n = 307; range, 0.26-0.87). The arithmetic mean of the basic density of the trunk-average of the density at breast height and at the top of the bole-was 0.675 +/- 0.101 (n = 307; range, 0.27-0.91). The mean basic density of the bole, adjusted for tapering, and using four samples along the bole, was 0.670 +/- 0.099 (n = 71; range, 0.38-0.86). The arithmetic mean of the basic density for the same trees was 0.675 +/- 0.098 (range, 0.39-0.87). The basic density of central heartwood was 0.766 +/- 0.158 (n = 149; range, 0.34-1.06). Significant differences exist between the various published estimates for Amazonian forest biomass and emissions, but we emphasize that revision of density values based on the present study will not reduce these discrepancies; instead, all estimates will shift in parallel to lower levels. Adjustments to biomass and emissions are sufficiently large to be significant for the global carbon balance. For example, an estimate of net committed emissions of 249 x 10(6) Mg CO2-equivalent C/year for Brazilian Amazonia in the 1990, of which 237 x 10(6) Mg CO2-equivalent C/ year was from net removal of biomass, would be reduced by 14 x 10(6) Mg CO2-equivalent C/year (5.7%: larger than the 5.3% adjustment to gross emissions because regrowth estimates remain unchanged). Decrease of similar proportions would apply throughout the tropics. For the 1980s, these downward adjustments total 113 x 10(6) Mg C/year for CO2 effects alone, or approximately 132 Mg CO2-equivalent C/year including trace gases. (c) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{nogueira_wood_2005, author = {Nogueira, E. M. and Nelson, B. W. and Fearnside, P. M.}, title = {Wood density in dense forest in central Amazonia, Brazil}, journal = {Forest Ecology and Management}, year = {2005}, volume = {208}, number = {1-3}, pages = {261--286}, url = {://WOS:000227860700019}, doi = {https://doi.org/10.1016/j.foreco.2004.12.007} } |
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Nogueira, E.M., Fearnside, P.M., Nelson, B.W., Barbosa, R.I. and Hermanus Keizer, E.W. | Estimates of forest biomass in the Brazilian Amazon: New allometric equations and adjustments to biomass from wood-volume inventories | 2008 | Forest Ecology and Management Vol. 256(11), pp. 1853-1867 |
article | DOI URL |
Abstract: Uncertainties in biomass estimates in Amazonian forests result in abroad range of possible magnitude for the emissions of carbon from deforestation and other land-use changes. This paper presents biomass equations developed from trees directly weighed in open forest on fertile soils in the southern Amazon (SA) and allometric equations for bole-volume estimates of trees in both dense and open forests. The equations were used to improve the commonly used biomass models based on large-scale wood-volume inventories carried out in Amazonian forest. The biomass estimates from the SA allometric equation indicate that equations developed in forests on infertile soils in central Amazonia (CA) result in overestimates if applied to trees in the open forests of SA. All aboveground components of 267 trees in open forests of SA were cut and weighed, and the proportion of the biomass stored in the crowns of trees in open forest was found to be higher than in dense forest. In the case of inventoried wood volume, corrections were applied for indentations and hollow trunks and it was determined that no adjustment is needed for the form factor used in the RadamBrasil volume formula. New values are suggested for use in models to convert wood volume to biomass estimates. A biomass map for Brazilian Amazonia was produced from 2702 plots inventoried by the RadamBrasil Project incorporating all corrections for wood density and wood volume and in factors used to add the bole volume of small trees and the crown biomass. Considering all adjustments, the biomass map indicates total biomass of 123.1 Gt (1 Gt = 1 billion tons) dry weight (aboveground + belowground) for originally forested areas in 1976 in the Brazilian Legal Amazon as a whole (102.3 Gt for aboveground only) at the time of the RadamBrasil inventories, which were carried out before intensive deforestation had occurred in the region. Excluded from this estimate are 529,000 km(2) of forest lacking sufficient RadamBrasil inventory data. After forest losses of 676,000 km(2) by 2006 - not counting 175,000 km(2) of this deforested area lacking RadamBrasil data - the estimated dry biomass stock was reduced to 105.4 and 87.6 Gt (aboveground + belowground and only above-ground). Thus, in 2006 the carbon storage in forested areas in Brazilian Amazonia as a whole will be around 51.1 Gt (assuming 1 Mg dry biomass = 0.485 Mg C. Biomass estimates by forest type (aggregated into 12 vegetation classes) are provided for each state in the Brazilian Legal Amazon. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{nogueira_estimates_2008, author = {Nogueira, Euler Melo and Fearnside, Philip Martin and Nelson, Bruce Walker and Barbosa, Reinaldo Imbrozio and Hermanus Keizer, Edwin Willem}, title = {Estimates of forest biomass in the Brazilian Amazon: New allometric equations and adjustments to biomass from wood-volume inventories}, journal = {Forest Ecology and Management}, year = {2008}, volume = {256}, number = {11}, pages = {1853--1867}, url = {://WOS:000261115800005}, doi = {https://doi.org/10.1016/j.foreco.2008.07.022} } |
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Nogueira, D.S. and Sá, L.D.d.A. | Estudo de rajadas de vento noturnas na floresta de Caxiuanã durante o experimento COBRA-PARÁ [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial, pp. 161-164 |
article | |
BibTeX:
@article{nogueira_estudo_2007, author = {Nogueira, Daniele Santos and Sá, Leonardo Deane de Abreu}, title = {Estudo de rajadas de vento noturnas na floresta de Caxiuanã durante o experimento COBRA-PARÁ}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial}, pages = {161--164} } |
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Nogueira, D.S. and Sá, L.D.A. | Fenômeno de intermitência global na camada limite noturna: Estudo de caso acima da floresta de Caxiuanã, PA [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 173-176 |
article | |
BibTeX:
@article{nogueira_fenomeno_2009, author = {Nogueira, Daniele S. and Sá, Leonardo D. A.}, title = {Fenômeno de intermitência global na camada limite noturna: Estudo de caso acima da floresta de Caxiuanã, PA}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {173--176} } |
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Nogueira, S., L.D.A., C. and J.C.P., D. | Rajadas Noturnas e Trocas de CO2 acima da Reserva Florestal de Caxiuanã, PA, durante a estação seca [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3b), pp. 213-223 |
article | |
BibTeX:
@article{nogueira_rajadas_2006, author = {Nogueira, Sa, L.D.A., Cohen, J.C.P., D.S.}, title = {Rajadas Noturnas e Trocas de CO2 acima da Reserva Florestal de Caxiuanã, PA, durante a estação seca}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3b}, pages = {213--223} } |
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Nobre, C.A., Sampaio, G., Borma, L.S., Castilla-Rubio, J.C., Silva, J.S. and Cardoso, M. | Land-use and climate change risks in the Amazon and the need of a novel sustainable development paradigm [BibTeX] |
2016 | Proceedings of the National Academy of Sciences of the United States of American Vol. 113(39), pp. 10759-10768 |
article | DOI |
BibTeX:
@article{nobre_land-use_2016, author = {Nobre, Carlos A. and Sampaio, Gilvan and Borma, Laura S. and Castilla-Rubio, Juan Carlos and Silva, José S. and Cardoso, Manoel}, title = {Land-use and climate change risks in the Amazon and the need of a novel sustainable development paradigm}, journal = {Proceedings of the National Academy of Sciences of the United States of American}, year = {2016}, volume = {113}, number = {39}, pages = {10759--10768}, doi = {https://doi.org/10.1073/pnas.1605516113} } |
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Nobre, C.A., Obregón, G.O., Marengo, J., Fu, R. and Poveda, G. | Characteristics of Amazonian Climate: Main Features [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 149-162 |
incollection | |
BibTeX:
@incollection{m_keller_characteristics_2009, author = {Nobre, C. A. and Obregón, G. O. and Marengo, J.A. and Fu, R. and Poveda, G.}, title = {Characteristics of Amazonian Climate: Main Features}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {149--162} } |
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Nobre, C.A. and Lahsen, M. | Desenvolvimento Sustentável na Amazônia: Desafios, Potencial e o Papel da Ciência e Tecnologia [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 291-300 |
incollection | |
BibTeX:
@incollection{batistella_desenvolvimento_2008, author = {Nobre, Carlos A. and Lahsen, Myanna}, title = {Desenvolvimento Sustentável na Amazônia: Desafios, Potencial e o Papel da Ciência e Tecnologia}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {291--300}, note = {Section: 3} } |
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Nobre, C.A. and Borma, L.D.S. | 'Tipping points' for the Amazon forest | 2009 | Current Opinion in Environmental Sustainability Vol. 1(1), pp. 28-36 |
article | DOI URL |
Abstract: The stability of the Amazon forest-climate equilibrium is being perturbed by a number of human drivers of change (e.g. deforestation, global warming, forest fires, higher CO(2) concentrations, and increased frequency of droughts and floods). Quantitative assessments for the maintenance of the tropical forest indicate that 'tipping points' may exist for total deforested area (textgreater40%) and for global warming (Delta T textgreater 3-4 degrees C). The likelihood of exceeding a tipping point can be greatly exacerbated by increases in forest fires and droughts, but quantification of those effects is still lacking. Forest resilience can be significantly increased if CO(2) 'fertilization' effect is proven to be taking place for tropical forests, but it can be offset by continued increases in temperature, rainfall seasonality, and forest fires. | |||||
BibTeX:
@article{nobre_tipping_2009, author = {Nobre, Carlos Afonso and Borma, Laura De Simone}, title = {'Tipping points' for the Amazon forest}, journal = {Current Opinion in Environmental Sustainability}, year = {2009}, volume = {1}, number = {1}, pages = {28--36}, url = {://WOS:000282413600005}, doi = {https://doi.org/10.1016/j.cosust.2009.07.003} } |
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Nobre, C.A., Artaxo, P., Assuncao, M., Dias, F.S., Victoria, R.L., Nobre, A.D. and Krug, T. | The Amazon Basin and land-cover change: A future in the balance? [BibTeX] |
2002 | Challenges of a Changing Earth, pp. 137-141 | incollection | URL |
BibTeX:
@incollection{steffen_amazon_2002, author = {Nobre, C. A. and Artaxo, P. and Assuncao, M. and Dias, F. S. and Victoria, R. L. and Nobre, A. D. and Krug, T.}, title = {The Amazon Basin and land-cover change: A future in the balance?}, booktitle = {Challenges of a Changing Earth}, year = {2002}, pages = {137--141}, url = {://WOS:000179874000025} } |
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Nobre, J.M. and P. Artaxo, C. | Understanding the climate of Amazonia: Progress from LBA [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 145-148 |
incollection | |
BibTeX:
@incollection{m_keller_understanding_2009, author = {Nobre, J. Marengo, P. Artaxo, C.}, title = {Understanding the climate of Amazonia: Progress from LBA}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {145--148} } |
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Nobre, A., Cuartas, L., Hodnett, M., Rennó, C., Rodrigues, G., Silveira, A., Waterloo, M. and Saleska, S. | Height Above the Nearest Drainage - a hydrologically relevant new terrain model | 2011 | Journal of Hydrology Vol. 404(1-2), pp. 13-29 |
article | DOI URL |
Abstract: This paper introduces a new terrain model named HAND, and reports on the calibration and validation of landscape classes representing soil environments in Amazonia, which were derived using it. The HAND model normalizes topography according to the local relative heights found along the drainage network, and in this way, presents the topology of the relative soil gravitational potentials, or local draining potentials. The HAND model has been demonstrated to show a high correlation with the depth of the water table, providing an accurate spatial representation of soil water environments. Normalized draining potentials can be classified according to the relative vertical flowpath-distances to the nearest drainages, defining classes of soil water environments. These classes have been shown to be comparable and have verifiable and reproducible hydrological significance across the studied catchment and for surrounding ungauged catchments. The robust validation of this model over an area of 18,000 km(2) in the lower Rio Negro catchment has demonstrated its capacity to map expansive environments using only remotely acquired topography data as inputs. The classified HAND model has also preliminarily demonstrated robustness when applied to ungauged catchments elsewhere with contrasting geologies, geomorphologies and soil types. The HAND model and the derived soil water maps can help to advance physically based hydrological models and be applied to a host of disciplines that focus on soil moisture and ground water dynamics. As an original assessment of soil water in the landscape, the HAND model explores the synergy between digital topography data and terrain modeling, presenting an opportunity for solving many difficult problems in hydrology. (C) 2011 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{nobre_height_2011, author = {Nobre, A.D. and Cuartas, L.A. and Hodnett, M. and Rennó, C.D. and Rodrigues, G. and Silveira, A. and Waterloo, M. and Saleska, S.}, title = {Height Above the Nearest Drainage - a hydrologically relevant new terrain model}, journal = {Journal of Hydrology}, year = {2011}, volume = {404}, number = {1-2}, pages = {13--29}, url = {://000292367700002}, doi = {https://doi.org/10.1016/j.jhydrol.2011.03.051} } |
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Neves, T.T.d.A.T. and Fisch, G. | Formação de uma camada limite misturada durante o período noturno no experimento RaCCI/LBA 2002 [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 181-184 |
article | |
BibTeX:
@article{neves_formacao_2009, author = {Neves, T. T. de A. T. and Fisch, G.}, title = {Formação de uma camada limite misturada durante o período noturno no experimento RaCCI/LBA 2002}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {181--184} } |
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Neves, T. and Fisch, G. | The Daily Cycle of the Atmospheric Boundary Layer Heights over Pasture Site in Amazonia [BibTeX] |
2015 | American Journal of Environmental Engineering Vol. 5(1A), pp. 39-44 |
article | DOI |
BibTeX:
@article{neves_daily_2015, author = {Neves, T.T.A.T. and Fisch, G.}, title = {The Daily Cycle of the Atmospheric Boundary Layer Heights over Pasture Site in Amazonia}, journal = {American Journal of Environmental Engineering}, year = {2015}, volume = {5}, number = {1A}, pages = {39--44}, doi = {https://doi.org/10.5923/s.ajee.201501.06} } |
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Neves, T. and Fisch, G. | Camada limite noturna sobre área de pastagem na amazônia [BibTeX] |
2011 | Revista Brasileira de Meteorologia Vol. 26(4), pp. 619 - 628 |
article | |
BibTeX:
@article{neves_camada_2011, author = {Neves, T.T.A.T. and Fisch, G.}, title = {Camada limite noturna sobre área de pastagem na amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2011}, volume = {26}, number = {4}, pages = {619 -- 628} } |
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Neves, T., Fisch, G. and Raasch, S. | Local Convection and Turbulence in the Amazonia Using Large Eddy Simulation Model [BibTeX] |
2018 | Atmosphere Vol. 9(10), pp. 399 |
article | DOI |
BibTeX:
@article{neves_local_2018, author = {Neves, T. and Fisch, G. and Raasch, S.}, title = {Local Convection and Turbulence in the Amazonia Using Large Eddy Simulation Model}, journal = {Atmosphere}, year = {2018}, volume = {9}, number = {10}, pages = {399}, doi = {https://doi.org/10.3390/atmos9100399} } |
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Neu, V., Ward, N.D., Krusche, A.V. and Neill, C. | Dissolved Organic and Inorganic Carbon Flow Paths in an Amazonian Transitional Forest [BibTeX] |
2016 | Frontiers in Marine Science Vol. 3, pp. 1-15 |
article | |
BibTeX:
@article{neu_dissolved_2016, author = {Neu, V. and Ward, N. D. and Krusche, A. V. and Neill, C.}, title = {Dissolved Organic and Inorganic Carbon Flow Paths in an Amazonian Transitional Forest}, journal = {Frontiers in Marine Science}, year = {2016}, volume = {3}, pages = {1--15} } |
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Neu, V., Neill, C. and Krusche, A.V. | Gaseous and fluvial carbon export from an Amazon forest watershed | 2011 | Biogeochemistry Vol. 105(1-3), pp. 133-147 |
article | DOI URL |
Abstract: The transfer of carbon (C) from Amazon forests to aquatic ecosystems as CO(2) supersaturated in groundwater that outgases to the atmosphere after it reaches small streams has been postulated to be an important component of terrestrial ecosystem C budgets. We measured C losses as soil respiration and methane (CH(4)) flux, direct CO(2) and CH(4) fluxes from the stream surface and fluvial export of dissolved inorganic C (DIC), dissolved organic C (DOC), and particulate C over an annual hydrologic cycle from a 1,319-ha forested Amazon perennial first-order headwater watershed at Tanguro Ranch in the southern Amazon state of Mato Grosso. Stream pCO(2) concentrations ranged from 6,491 to 14,976 mu atm and directly-measured stream CO(2) outgassing flux was 5,994 +/- A 677 g C m(-2) y(-1) of stream surface. Stream pCH(4) concentrations ranged from 291 to 438 mu atm and measured stream CH(4) outgassing flux was 987 +/- A 221 g C m(-2) y(-1). Despite high flux rates from the stream surface, the small area of stream itself (970 m(2), or 0.007% of watershed area) led to small directly-measured annual fluxes of CO(2) (0.44 +/- A 0.05 g C m(2) y(-1)) and CH(4) (0.07 +/- A 0.02 g C m(2) y(-1)) per unit watershed land area. Measured fluvial export of DIC (0.78 +/- A 0.04 g C m(-2) y(-1)), DOC (0.16 +/- A 0.03 g C m(-2) y(-1)) and coarse plus fine particulate C (0.001 +/- A 0.001 g C m(-2) y(-1)) per unit watershed land area were also small. However, stream discharge accounted for only 12% of the modeled annual watershed water output because deep groundwater flows dominated total runoff from the watershed. When C in this bypassing groundwater was included, total watershed export was 10.83 g C m(-2) y(-1) as CO(2) outgassing, 11.29 g C m(-2) y(-1) as fluvial DIC and 0.64 g C m(-2) y(-1) as fluvial DOC. Outgassing fluxes were somewhat lower than the 40-50 g C m(-2) y(-1) reported from other Amazon watersheds and may result in part from lower annual rainfall at Tanguro. Total stream-associated gaseous C losses were two orders of magnitude less than soil respiration (696 +/- A 147 g C m(-2) y(-1)), but total losses of C transported by water comprised up to about 20% of the +/- A 150 g C m(-2) (+/- 1.5 Mg C ha(-1)) that is exchanged annually across Amazon tropical forest canopies. | |||||
BibTeX:
@article{neu_gaseous_2011, author = {Neu, V. and Neill, C. and Krusche, A. V.}, title = {Gaseous and fluvial carbon export from an Amazon forest watershed}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {133--147}, url = {://WOS:000294501100010}, doi = {https://doi.org/10.1007/s10533-011-9581-3} } |
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Nepstad, D.C., Verissimo, A., Alencar, A., Nobre, C., Lima, E., Lefebvre, P., Schlesinger, P., Potter, C., Moutinho, P., Mendoza, E., Cochrane, M. and Brooks, V. | Large-scale impoverishment of Amazonian forests by logging and fire | 1999 | Nature Vol. 398(6727), pp. 505-508 |
article | DOI URL |
Abstract: Amazonian deforestation rates are used to determine human effects on the global carbon cycle(1-3) and to measure Brazil's progress in curbing forest impoverishment(1,4,5). But this widely used measure of tropical land use tells only part of the story. Here we present field surveys of wood mills and forest burning across Brazilian Amazonia which show that logging crews severely damage 10,000 to 15,000 km(2) yr(-1) of forest that are not included in deforestation mapping programmes. Moreover, we find that surface fires burn additional large areas of standing forest, the destruction of which is normally not documented. Forest impoverishment due to such fires may increase dramatically when severe droughts provoke forest leaf-shedding and greater flammability; our regional water-balance model indicates that an estimated 270,000 km(2) of forest became vulnerable to fire in the 1998 dry season. Overall, we find that present estimates of annual deforestation for Brazilian Amazonia capture less than half of the forest area that is impoverished each year, and even less during; years of severe drought. Both logging and fire increase forest vulnerability to future burning(6,7) and release forest carbon stocks to the atmosphere, potentially doubling net carbon emissions from regional land-use during severe El Nino episodes. If this forest impoverishment is to be controlled, then logging activities need to be restricted or replaced with low-impact timber harvest techniques, and more effective strategies to prevent accidental forest fires need to be implemented. | |||||
BibTeX:
@article{nepstad_large-scale_1999, author = {Nepstad, D. C. and Verissimo, A. and Alencar, A. and Nobre, C. and Lima, E. and Lefebvre, P. and Schlesinger, P. and Potter, C. and Moutinho, P. and Mendoza, E. and Cochrane, M. and Brooks, V.}, title = {Large-scale impoverishment of Amazonian forests by logging and fire}, journal = {Nature}, year = {1999}, volume = {398}, number = {6727}, pages = {505--508}, url = {://WOS:000079662800046}, doi = {https://doi.org/10.1038/19066} } |
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Nepstad, D.C., Tohver, I.M., Ray, D., Moutinho, P. and Cardinot, G. | Mortality of large trees and lianas following experimental drought in an amazon forest | 2007 | Ecology Vol. 88(9), pp. 2259-2269 |
article | DOI URL |
Abstract: Severe drought episodes such as those associated with El Nifio Southern Oscillation (ENSO) events influence large areas of tropical forest and may become more frequent in the future. One of the most important forest responses to severe drought is tree mortality, which alters forest structure, composition, carbon content, and flammability, and which varies widely. This study tests the hypothesis that tree mortality increases abruptly during drought episodes when plant-available soil water (PAW) declines below a critical minimum threshold. It also examines the effect of tree size, plant life form (palm, liana, tree) and potential canopy position (understory, midcanopy, overstory) on drought-induced plant mortality. A severe, four-year drought episode was simulated by excluding 60% of incoming throughfall during each wet season using plastic panels installed in the understory of a 1-ha forest treatment plot, while a 1-ha control plot received normal rainfall. After 3.2 years, the treatment resulted in a 38% increase in mortality rates across all stems textgreater 2 cm dbh. Mortality rates increased 4.5-fold among large trees (textgreater 30 cm dbh) and twofold among medium trees (10-30 cm dbh) in response to the treatment, whereas the smallest stems were less responsive. Recruitment rates did not compensate for the elevated mortality of larger-diameter stems in the treatment plot. Overall, lianas proved more susceptible to drought-induced mortality than trees or palms, and potential overstory tree species were more vulnerable than mideanopy and understory species. Large stems contributed to 90% of the pretreatment live aboveground biomass in both plots. Large-tree mortality resulting from the treatment generated 3.4 times more dead biomass than the control plot. The dramatic mortality response suggests significant, adverse impacts on the global carbon cycle if climatic changes follow current trends. | |||||
BibTeX:
@article{nepstad_mortality_2007, author = {Nepstad, Daniel C. and Tohver, Ingrid Marisa and Ray, David and Moutinho, Paulo and Cardinot, Georgina}, title = {Mortality of large trees and lianas following experimental drought in an amazon forest}, journal = {Ecology}, year = {2007}, volume = {88}, number = {9}, pages = {2259--2269}, note = {Edition: 2007/10/09}, url = {://WOS:000249500900012}, doi = {https://doi.org/10.1890/06-1046.1} } |
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Nepstad, D.C., Stickler, C.M., Soares-Filho, B. and Merry, F. | Interactions among Amazon land use, forests and climate: prospects for a near-term forest tipping point | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1737-1746 |
article | DOI URL |
Abstract: Some model experiments predict a large-scale substitution of Amazon forest by savannah-like vegetation by the end of the twenty-first century. Expanding global demands for biofuels and grains, positive feedbacks in the Amazon forest fire regime and drought may drive a faster process of forest degradation that could lead to a near-term forest dieback. Rising worldwide demands for biofuel and meat are creating powerful new incentives for agro-industrial expansion into Amazon forest regions. Forest fires, drought and logging increase susceptibility to further burning while deforestation and smoke can inhibit rainfall, exacerbating fire risk. If sea surface temperature anomalies (such as El Nino episodes) and associated Amazon droughts of the last decade continue into the future, approximately 55% of the forests of the Amazon will be cleared, logged, damaged by drought or burned over the next 20 years, emitting 15-26 Pg of carbon to the atmosphere. Several important trends could prevent a near-term dieback. As fire-sensitive investments accumulate in the landscape, property holders use less fire and invest more in fire control. Commodity markets are demanding higher environmental performance from farmers and cattle ranchers. Protected areas have been established in the pathway of expanding agricultural frontiers. Finally, emerging carbon market incentives for reductions in deforestation could support these trends. | |||||
BibTeX:
@article{nepstad_interactions_2008, author = {Nepstad, Daniel C. and Stickler, Claudia M. and Soares-Filho, Britaldo and Merry, Frank}, title = {Interactions among Amazon land use, forests and climate: prospects for a near-term forest tipping point}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1737--1746}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500003}, doi = {https://doi.org/10.1098/rstb.2007.0036} } |
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Nepstad, D.C., Stickler, C.M. and Almeida, O.T. | Globalization of the Amazon soy and beef industries: Opportunities for conservation | 2006 | Conservation Biology Vol. 20(6), pp. 1595-1603 |
article | DOI URL |
Abstract: Amazon beef and soybean industries, the primary drivers of Amazon deforestation, are increasingly responsive to economic signals emanating from around the world, such as those associated with bovine spongiform encephalopathy (BSE, "mad cow disease") outbreaks and China's economic growth. The expanding role of these economic "teleconnections" (coupled phenomena that take place in distant places on the planet) led to a 3-year period (2002-2004) of historically high deforestation rates. But it also increases the potential for large-scale conservation in the region as markets and finance institutions demand better environmental and social performance of beef and soy producers. Cattle ranchers and soy farmers who have generally opposed ambitious government regulations that require forest reserves on private property are realizing that good land stewardship-including compliance with legislation-may increase their access to expanding domestic and international markets and to credit and lower the risk of "losing" their land to agrarian reform. The realization of this potential depends on the successful negotiation of social and environmental performance criteria and an associated system of certification that are acceptable to both the industries and civil society. The foot-and-mouth eradication system, in which geographic zones win permission to export beef, may provide an important model for the design of a low-cost, peer-enforced, socio environmental certification system that becomes the mechanism by which beef and soy industries gain access to markets outside the Amazon. | |||||
BibTeX:
@article{nepstad_globalization_2006, author = {Nepstad, Daniel C. and Stickler, Claudia M. and Almeida, Oriana T.}, title = {Globalization of the Amazon soy and beef industries: Opportunities for conservation}, journal = {Conservation Biology}, year = {2006}, volume = {20}, number = {6}, pages = {1595--1603}, note = {Edition: 2006/12/22}, url = {://WOS:000242724500009}, doi = {https://doi.org/10.1111/j.1523-1739.2006.00510.x} } |
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Nepstad, D.C., Moutinho, P., Dias, M.B., Davidson, E., Cardinot, G., Markewitz, D., Figueiredo, R., Vianna, N., Chambers, J., Ray, D., Guerreiros, J.B., Lefebvre, P., Sternberg, L., Moreira, M., Barros, L., Ishida, F.Y., Tohlver, I., Belk, E., Kalif, K. and Schwalbe, K. | The effects of partial throughfall exclusion on canopy processes, aboveground production, and biogeochemistry of an Amazon forest | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Moist tropical forests in Amazonia and elsewhere are subjected to increasingly severe drought episodes through the El Nino-Southern Oscillation (ENSO) and possibly through deforestation-driven reductions in rainfall. The effects of this trend on tropical forest canopy dynamics, emissions of greenhouse gases, and other ecological functions are potentially large but poorly understood. We established a throughfall exclusion experiment in an east-central Amazon forest (Tapajos National Forest, Brazil) to help understand these effects. After 1-year intercalibration period of two 1-ha forest plots, we installed plastic panels and wooden gutters in the understory of one of the plots, thereby excluding similar to890 mm of throughfall during the exclusion period of 2000 (late January to early August) and similar to680 mm thus far in the exclusion period of 2001 (early January to late May). Average daily throughfall reaching the soil during the exclusion period in 2000 was 4.9 and 8.3 mm in the treatment and control plots and was 4.8 and 8.1 mm in 2001, respectively. During the first exclusion period, surface soil water content (0-2 m) declined by similar to100 mm, while deep soil water (2-11 m) was unaffected. During the second exclusion period, which began shortly after the dry season when soil water content was low, surface and deep soil water content declined by similar to140 and 160 mm, respectively. Although this depletion of soil water provoked no detectable increase in leaf drought stress (i.e., no reduction in predawn leaf water potential), photosynthetic capacity declined for some species, the canopy thinned (greater canopy openness and lower leaf area index) during the second exclusion period, stem radial growth of trees textless15 m tall declined, and fine litterfall declined in the treatment plot, as did tree fruiting. Aboveground net primary productivity (NPP) (stemwood increment and fine litter production) declined by one fourth, from 15.1 to 11.4 Mg ha(-1) yr(-1), in the treatment plot and decreased slightly, from 11.9 to 11.5 Mg ha(-1) yr(-1), in the control plot. Stem respiration varied seasonally and was correlated with stem radial growth but showed no treatment response. The fastest response to the throughfall exclusion, and the surface soil moisture deficits that it provoked, was found in the soil itself. The treatment reduced N2O emissions and increased CH4 consumption relative to the control plot, presumably in response to the improved soil aeration that is associated with soil drying. Our hypothesis that NO emissions would increase following exclusion was not supported. The conductivity and alkalinity of water percolating through the litter layer and through the mineral soil to a depth of 200 cm was higher in the treatment plot, perhaps because of the lower volume of water that was moving through these soil layers in this plot. Decomposition of the litter showed no difference between plots. In sum, the small soil water reductions provoked during the first 2 years of partial throughfall exclusion were sufficient to lower aboveground NPP, including the stemwood increment that determines the amount of carbon stored in the forest. These results suggest that the net accumulation of carbon in mature Amazon forests indicated by recent permanent plot and eddy covariance studies may be very sensitive to small reductions in rainfall. The soil water reductions were also sufficient to increase soil emissions of N2O and to increase soil consumption of CH4-both radiatively important gases in the atmosphere. The possible reduction of tree reproductive activity points to potentially important effects of drought on the long-term species composition of Amazon forests. | |||||
BibTeX:
@article{nepstad_effects_2002, author = {Nepstad, D. C. and Moutinho, P. and Dias, M. B. and Davidson, E. and Cardinot, G. and Markewitz, D. and Figueiredo, R. and Vianna, N. and Chambers, J. and Ray, D. and Guerreiros, J. B. and Lefebvre, P. and Sternberg, L. and Moreira, M. and Barros, L. and Ishida, F. Y. and Tohlver, I. and Belk, E. and Kalif, K. and Schwalbe, K.}, title = {The effects of partial throughfall exclusion on canopy processes, aboveground production, and biogeochemistry of an Amazon forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200084}, doi = {https://doi.org/10.1029/2001jd000360} } |
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Nepstad, D., Soares-Filho, B.S., Merry, F., Lima, A., Moutinho, P., Carter, J., Bowman, M., Cattaneo, A., Rodrigues, H., Schwartzman, S., McGrath, D.G., Stickler, C.M., Lubowski, R., Piris-Cabezas, P., Rivero, S., Alencar, A., Almeida, O. and Stella, O. | The End of Deforestation in the Brazilian Amazon [BibTeX] |
2009 | Science Vol. 326(5958), pp. 1350-1351 |
article | DOI URL |
BibTeX:
@article{nepstad_end_2009, author = {Nepstad, Daniel and Soares-Filho, Britaldo S. and Merry, Frank and Lima, Andre and Moutinho, Paulo and Carter, John and Bowman, Maria and Cattaneo, Andrea and Rodrigues, Hermann and Schwartzman, Stephan and McGrath, David G. and Stickler, Claudia M. and Lubowski, Ruben and Piris-Cabezas, Pedro and Rivero, Sergio and Alencar, Ane and Almeida, Oriana and Stella, Osvaldo}, title = {The End of Deforestation in the Brazilian Amazon}, journal = {Science}, year = {2009}, volume = {326}, number = {5958}, pages = {1350--1351}, note = {Edition: 2009/12/08}, url = {://WOS:000272351100023}, doi = {https://doi.org/10.1126/science.1182108} } |
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Nepstad, D., Schwartzman, S., Bamberger, B., Santilli, M., Ray, D., Schlesinger, P., Lefebvre, P., Alencar, A., Prinz, E., Fiske, G. and Rolla, A. | Inhibition of Amazon deforestation and fire by parks and indigenous lands | 2006 | Conservation Biology Vol. 20(1), pp. 65-73 |
article | DOI URL |
Abstract: Conservation scientists generally agree that many types of protected areas will be needed to protect tropical forests. But little is known of the comparative performance of inhabited and uninhabited reserves in slowing the most extreme form of forest disturbance: conversion to agriculture. We used satellite-based maps of land cover and fire occurrence in the Brazilian Amazon to compare the performance of large (textgreater 10, 000 ha) uninhabited (parks) and inhabited (indigenous lands, extractive reserves, and national forests) reserves. Reserves significantly reduced both deforestation and fire. Deforestation was 1.7 (extractive reserves) to 20 (parks) times higher along the outside versus the inside of the reserve perimeters and fire occurrence was 4 (indigenous lands) to 9 (national forests) times higher. No strong difference in the inhibition of deforestation (p = 0.11) or fire (p = 0.34) was found between parks and indigenous lands. However, uninhabited reserves tended to be located away from areas of high deforestation and burning rates. In contrast, indigenous lands were often created in response to frontier expansion, and many prevented deforestation completely despite high rates of deforestation along their boundaries. The inhibitory effect of indigenous lands on deforestation was strong after centuries of contact with the national society and was not correlated with indigenous population density. Indigenous lands occupy one fifth of the Brazilian Amazon five times the area under protection in parks-and are currently the most important barrier to Amazon deforestation. As the protected-area network expands from 36% to 41 % of the Brazilian Amazon over the coming years, the greatest challenge will be successful reserve implementation in high-risk areas of frontier expansion as indigenous lands are strengthened. This success will depend on a broad base of political support. | |||||
BibTeX:
@article{nepstad_inhibition_2006, author = {Nepstad, D. and Schwartzman, S. and Bamberger, B. and Santilli, M. and Ray, D. and Schlesinger, P. and Lefebvre, P. and Alencar, A. and Prinz, E. and Fiske, G. and Rolla, A.}, title = {Inhibition of Amazon deforestation and fire by parks and indigenous lands}, journal = {Conservation Biology}, year = {2006}, volume = {20}, number = {1}, pages = {65--73}, note = {Edition: 2006/08/17}, url = {://WOS:000235367100008}, doi = {https://doi.org/10.1111/j.1523-1739.2006.00351.x} } |
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Nepstad, D., Moreira, A., Verissimo, A., Lefebvre, P., Schlesinger, P., Potter, C., Nobre, C., Setter, A., Krug, T., Barros, A.C., Alencar, A. and Pereira, J.R. | Forest fire prediction and prevention in the Brazilian Amazon [BibTeX] |
1998 | Conservation Biology Vol. 12(5), pp. 951-953 |
article | DOI URL |
BibTeX:
@article{nepstad_forest_1998, author = {Nepstad, D. and Moreira, A. and Verissimo, A. and Lefebvre, P. and Schlesinger, P. and Potter, C. and Nobre, C. and Setter, A. and Krug, T. and Barros, A. C. and Alencar, A. and Pereira, J. R.}, title = {Forest fire prediction and prevention in the Brazilian Amazon}, journal = {Conservation Biology}, year = {1998}, volume = {12}, number = {5}, pages = {951--953}, url = {://WOS:000076272800007}, doi = {https://doi.org/10.1046/j.1523-1739.1998.012005951.x} } |
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Nepstad, D., McGrath, D., Alencar, A., Barros, C., Carvalho, G., Santilli, M. and Diaz, M.D.V. | Issues in Amazonian development - Response [BibTeX] |
2002 | Science Vol. 295(5560), pp. 1643-1644 |
article | URL |
BibTeX:
@article{nepstad_issues_2002, author = {Nepstad, D. and McGrath, D. and Alencar, A. and Barros, C. and Carvalho, G. and Santilli, M. and Diaz, M. D. V.}, title = {Issues in Amazonian development - Response}, journal = {Science}, year = {2002}, volume = {295}, number = {5560}, pages = {1643--1644}, url = {://WOS:000174212900020} } |
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Nepstad, D., McGrath, D., Alencar, A., Barros, A.C., Carvalho, G., Santilli, M. and Diaz, M.D.V. | Environment - Frontier governance in Amazonia [BibTeX] |
2002 | Science Vol. 295(5555), pp. 629-+ |
article | DOI URL |
BibTeX:
@article{nepstad_environment_2002, author = {Nepstad, D. and McGrath, D. and Alencar, A. and Barros, A. C. and Carvalho, G. and Santilli, M. and Diaz, M. D. V.}, title = {Environment - Frontier governance in Amazonia}, journal = {Science}, year = {2002}, volume = {295}, number = {5555}, pages = {629--+}, note = {Edition: 2002/01/26}, url = {://WOS:000173560900025}, doi = {https://doi.org/10.1126/science.1067053} } |
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Nepstad, D., Lefebvre, P., Da Silva, U.L., Tomasella, J., Schlesinger, P., Solorzano, L., Moutinho, P., Ray, D. and Benito, J.G. | Amazon drought and its implications for forest flammability and tree growth: a basin-wide analysis | 2004 | Global Change Biology Vol. 10(5), pp. 704-717 |
article | DOI URL |
Abstract: Severe drought in moist tropical forests provokes large carbon emissions by increasing forest flammability and tree mortality, and by suppressing tree growth. The frequency and severity of drought in the tropics may increase through stronger El Nino Southern Oscillation (ENSO) episodes, global warming, and rainfall inhibition by land use change. However, little is known about the spatial and temporal patterns of drought in moist tropical forests, and the complex relationships between patterns of drought and forest fire regimes, tree mortality, and productivity. We present a simple geographic information system soil water balance model, called RisQue (Risco de Queimada - Fire Risk) for the Amazon basin that we use to conduct an analysis of these patterns for 1996-2001. RisQue features a map of maximum plant-available soil water (PAW(max)) developed using 1565 soil texture profiles and empirical relationships between soil texture and critical soil water parameters. PAW is depleted by monthly evapotranspiration (ET) fields estimated using the Penman-Monteith equation and satellite-derived radiation inputs and recharged by monthly rain fields estimated from 266 meteorological stations. Modeled PAW to 10 m depth (PAW(10 m)) was similar to field measurements made in two Amazon forests. During the severe drought of 2001, PAW(10 m) fell to below 25% of PAW(max) in 31% of the region's forests and fell below 50% PAW(max) in half of the forests. Field measurements and experimental forest fires indicate that soil moisture depletion below 25% PAW(max) corresponds to a reduction in leaf area index of approximately 25%, increasing forest flammability. Hence, approximately one-third of Amazon forests became susceptible to fire during the 2001 ENSO period. Field measurements also suggest that the ENSO drought of 2001 reduced carbon storage by approximately 0.2 Pg relative to years without severe soil moisture deficits. RisQue is sensitive to spin-up time, rooting depth, and errors in ET estimates. Improvements in our ability to accurately model soil moisture content of Amazon forests will depend upon better understanding of forest rooting depths, which can extend to beyond 15 m. RisQue provides a tool for early detection of forest fire risk. | |||||
BibTeX:
@article{nepstad_amazon_2004, author = {Nepstad, D. and Lefebvre, P. and Da Silva, U. L. and Tomasella, J. and Schlesinger, P. and Solorzano, L. and Moutinho, P. and Ray, D. and Benito, J. G.}, title = {Amazon drought and its implications for forest flammability and tree growth: a basin-wide analysis}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {704--717}, url = {://WOS:000221421600013 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00772.x/asset/j.1529-8817.2003.00772.x.pdf?v=1&t=h6hwiijo&s=30a318916d7447c2b15f4be89dfd894b74be5d17}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00772.x} } |
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Nepstad, D., Carvalho, G., Barros, A.C., Alencar, A., Capobianco, J.P., Bishop, J., Moutinho, P., Lefebvre, P., Silva, U.L. and Prins, E. | Road paving, fire regime feedbacks, and the future of Amazon forests | 2001 | Forest Ecology and Management Vol. 154(3), pp. 395-407 |
article | DOI URL |
Abstract: Fire poses the greatest threat to the forests of Amazonia. The magnitude of this thr-eat is amplified by three positive feedback loops that drive the expansion of forest fire in the region: (1) Fire promotes drought, and therefore more fire, by releasing smoke into the atmosphere, thus reducing rainfall. Fire-assisted conversion of forests to pastures may also promote drought by increasing albedo and decreasing water vapor flux to the atmosphere, further inhibiting rainfall. (2) Fire increases the susceptibility of forests to recurrent burning by killing trees, thereby allowing sunlight to penetrate the forest interior, and increasing the fuel load on the forest floor. (3) Finally, fires also self-perpetuate by burning agricultural and forestry systems, discouraging landholders from making those fire-sensitive investments in their land that would allow them to move beyond their dependence upon fire as a management tool. The long-term reduction of Amazon fire, and its substantial costs to society, is most likely to emerge through investments and policy change that stimulate permanent agricultural and forestry production systems within existing frontiers while slowing the rate of frontier expansion. But the Brazilian government's plan to pave, recuperate or construct 6245 km of roads in the Amazon may have the opposite effect. We present research findings that the government plan would nearly double the area of forestland that is accessible by paved highways, including 192,000 km(2), of fire-prone forest. Our analysis finds that these roads will stimulate 120,000-270,000 km(2) of additional deforestation, and forest impoverishment through logging and understory fire, if the historical relationship between road paving and forest alteration by humans continues. Infrastructural investments are urgently needed in Amazonia to help integrate isolated urban centers into the market economy, to improve the quality of life for millions of rural Amazonians, and to improve the profitability of agribusiness in Brazil's agricultural belt. But as currently planned, these investments will have the ancillary effects of accelerating deforestation, logging, forest fire, smoke-related illness, and the displacement of small-scale farmers. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{nepstad_road_2001, author = {Nepstad, D. and Carvalho, G. and Barros, A. C. and Alencar, A. and Capobianco, J. P. and Bishop, J. and Moutinho, P. and Lefebvre, P. and Silva, U. L. and Prins, E.}, title = {Road paving, fire regime feedbacks, and the future of Amazon forests}, journal = {Forest Ecology and Management}, year = {2001}, volume = {154}, number = {3}, pages = {395--407}, url = {://WOS:000172287600005}, doi = {https://doi.org/10.1016/s0378-1127(01)00511-4} } |
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Nepstad, D., Azevedo-Ramos, C., Lima, E., McGrath, D., Pereira, C. and Merry, F. | Managing the Amazon timber industry [BibTeX] |
2004 | Conservation Biology Vol. 18(2), pp. 575-577 |
article | DOI URL |
BibTeX:
@article{nepstad_managing_2004, author = {Nepstad, D. and Azevedo-Ramos, C. and Lima, E. and McGrath, D. and Pereira, C. and Merry, F.}, title = {Managing the Amazon timber industry}, journal = {Conservation Biology}, year = {2004}, volume = {18}, number = {2}, pages = {575--577}, url = {://WOS:000220567300035}, doi = {https://doi.org/10.1111/j.1523-1739.2004.00551.x} } |
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Nelson, R.F., Kimes, D.S., Salas, W.A. and Routhier, M. | Secondary forest age and tropical forest biomass estimation using thematic mapper imagery [BibTeX] |
2000 | Bioscience Vol. 50(5), pp. 419-431 |
article | DOI URL |
BibTeX:
@article{nelson_secondary_2000, author = {Nelson, R. F. and Kimes, D. S. and Salas, W. A. and Routhier, M.}, title = {Secondary forest age and tropical forest biomass estimation using thematic mapper imagery}, journal = {Bioscience}, year = {2000}, volume = {50}, number = {5}, pages = {419--431}, url = {://WOS:000086808700005}, doi = {https://doi.org/10.1641/0006-3568(2000)050%5B0419:sfaatf%5D2.0.co;2} } |
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Nelson, B.W., Mesquita, R., Pereira, J.L.G., de Souza, S.G.A., Batista, G.T. and Couto, L.B. | Allometric regressions for improved estimate of secondary forest biomass in the central Amazon | 1999 | Forest Ecology and Management Vol. 117(1-3), pp. 149-167 |
article | DOI URL |
Abstract: Estimates of the sequestering of carbon by secondary forests - which occupy almost half the deforested area of the Brazilian Amazon - will be improved by the use of accurate allometric relationships for non-destructive measurement of standing biomass and by an evaluation of the suitability of existing equations for application in secondary forest. Species-specific and mixed-species regressions for estimating total above-ground dry weight (DW) were therefore developed using eight abundant secondary forest tree species in the central Amazon, Using only DBH as the input variable, the species-specific equations estimated DW of individual trees with an average error of 10-15%. For the mixed-species equations, developed using 132 trees from seven of the eight species (excluding Cecropia), average error in estimating DW of individual trees was 19.8% using only DBH and 15.0% using DBH plus specific density of the wood (SD). Average SD for each species can be substituted without increasing the error of the estimate. Adding total tree height (H) as an input variable provided only a slight reduction in error to 14.0%. Previously published mixed-species biomass regression models, based on primary and secondary forest trees of the Amazon, were also cross-validated against the trees of this study. Two of these models, based on primary forest plots and using only DBH as an input, overestimated biomass by 10-60% for central Amazonian secondary forest trees in the size range 5-25 cm. The overestimate was greatest for the larger trees. Including Cecropia in the test group will make the overestimate even greater. Those published equations using DBH, H and SD as inputs, whether from secondary or primary forest plots, showed better agreement with the sample-derived regressions and lower average errors in estimation of individual tree dry weights. (C) 1999 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{nelson_allometric_1999, author = {Nelson, B. W. and Mesquita, R. and Pereira, J. L. G. and de Souza, S. G. A. and Batista, G. T. and Couto, L. B.}, title = {Allometric regressions for improved estimate of secondary forest biomass in the central Amazon}, journal = {Forest Ecology and Management}, year = {1999}, volume = {117}, number = {1-3}, pages = {149--167}, url = {://WOS:000079390200011}, doi = {https://doi.org/10.1016/s0378-1127(98)00475-7} } |
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Neill, C., Steudler, P.A., Garcia-Montiel, D.C., Melillo, J.M., Feigl, B.J., Piccolo, M.C. and Cerri, C.C. | Rates and controls of nitrous oxide and nitric oxide emissions following conversion of forest to pasture in Rondonia | 2005 | Nutrient Cycling in Agroecosystems Vol. 71(1), pp. 1-15 |
article | DOI URL |
Abstract: Tropical soils are important sources of nitrous oxide (N(2)O) and nitric oxide (NO) emissions from the Earth's terrestrial ecosystems. Clearing of tropical rainforest for pasture has the potential to alter N(2)O and NO emissions from soils by altering moisture, nitrogen supply or other factors that control N oxide production. In this review we report annual rates of N(2)O and NO emissions from forest and pastures of different ages in the western Brazilian Amazon state of Rondonia and examine how forest clearing alters the major controls of N oxide production. Forests had annual N(2)O emissions of 1.7 to 4.3 kg N ha(-1) y(-1) and annual NO emissions of 1.4 kg N ha(-1) y(-1). Young pastures of 1-3 years old had higher N(2)O emissions than the original forest (3.1-5.1 kg N ha(-1) y(-1)) but older pastures of 6 years or more had lower emissions (0.1 to 0.4 kg N ha(-1) y(-1)). Both soil moisture and indices of soil N cycling were relatively poor predictors of N(2)O, NO and combined N(2)O + NO emissions. In forest, high N(2)O emissions occurred at soil moistures above 30% water-filled pore space, while NO emissions occurred at all measured soil moistures (18-43%). In pastures, low N availability led to low N(2)O and NO emissions across the entire range of soil moistures. Based on these patterns and results of field fertilization experiments, we concluded that: (1) nitrification was the source of NO from forest soils, (2) denitrification was not a major source of N(2)O production from forest soils or was not limited by NO(3)(-) supply, (3) denitrification was a major source of N(2)O production from pasture soils but only when NO(3)(-) was available, and (4) nitrification was not a major source of NO production in pasture soils. Pulse wettings after prolonged dry periods increased N(2)O and NO emissions for only short periods and not enough to appreciably affect annual emission rates. We project that Basin-wide, the effect of clearing for pasture in the future will be a small reduction in total N(2)O emissions if the extensive pastures of the Amazon continue to be managed in a way similar to current practices. In the future, both N(2)O and NO fluxes could increase if uses of pastures change to include greater use of N fertilizers or N-fixing crops. Predicting the consequences of these changes for N oxide production will require an understanding of how the processes of nitrification and denitrification interact with soil type and regional moisture regimes to control N(2)O and NO production from these new anthropogenic N sources. | |||||
BibTeX:
@article{neill_rates_2005, author = {Neill, C. and Steudler, P. A. and Garcia-Montiel, D. C. and Melillo, J. M. and Feigl, B. J. and Piccolo, M. C. and Cerri, C. C.}, title = {Rates and controls of nitrous oxide and nitric oxide emissions following conversion of forest to pasture in Rondonia}, journal = {Nutrient Cycling in Agroecosystems}, year = {2005}, volume = {71}, number = {1}, pages = {1--15}, url = {://WOS:000227778700002}, doi = {https://doi.org/10.1007/s10705-004-0378-9} } |
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Neill, C., Piccolo, M.C., Melillo, J.M., Steudler, P.A. and Cerri, C.C. | Nitrogen dynamics in Amazon forest and pasture soils measured by N-15 pool dilution | 1999 | Soil Biology & Biochemistry Vol. 31(4), pp. 567-572 |
article | DOI URL |
Abstract: Clearing tropical forests of the Amazon Basin for pasture alters rates of soil nitrogen cycling. Previous studies have shown that rates of soil net N mineralization and net nitrification are lower in established pastures than in forests. We compared soil inorganic N concentrations, rates of net and gross mineralization and net and gross nitrification in a chronosequence and an experimental slash-and-burn plot in Rondonia. Soils of pastures 4, 10 and 21-yr-old contained more NH4+ and less NO3- than soils of forest. Soil NH4+ and NO3- concentrations were elevated for 2 months after burning but were similar to pools in the forest after 8.5 months. Rates of net N mineralization and net nitrification decreased from forest to 21-yr-old pasture. Rates of gross N mineralization were similar in forest, 4- and 10-yr-old pasture then declined in 21-yr-old pasture. These findings indicate that when forests are converted to pasture, soil N turnover is maintained for a period of a decade or longer, but N turnover eventually slows in old pastures. As older pastures come to dominate deforested regions of the Amazon, the total N cycled in soils of the region is likely to decrease, but not as quickly as studies based on net mineralization and net nitrification alone would indicate. (C) 1999 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{neill_nitrogen_1999, author = {Neill, C. and Piccolo, M. C. and Melillo, J. M. and Steudler, P. A. and Cerri, C. C.}, title = {Nitrogen dynamics in Amazon forest and pasture soils measured by N-15 pool dilution}, journal = {Soil Biology & Biochemistry}, year = {1999}, volume = {31}, number = {4}, pages = {567--572}, url = {://WOS:000079310800010}, doi = {https://doi.org/10.1016/s0038-0717(98)00159-x} } |
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Neill, C., Elsenbeer, H., Krusche, A.V., Lehmann, J., Markewitz, D. and Figueiredo, R.d.O. | Hydrological and biogeochemical processes in a changing Amazon: results from small watershed studies and the large-scale biosphere-atmosphere experiment | 2006 | Hydrological Processes Vol. 20(12), pp. 2467-2476 |
article | DOI URL |
Abstract: The Amazon Basin is the world's largest tropical forest region and one where rapid human changes to land cover have the potential to cause significant changes to hydrological and biogeochemical processes. The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multidisciplinary, multinational research program led by Brazil. The goal of LBA is to understand how the Amazon Basin functions as a regional entity in the earth system and how these functions are changing as a result of ongoing human activity. This compilation of nine papers focuses on a central LBA question in the area of nutrient dynamics and surface water chemistry-how do changes in land use alter fluxes of dissolved and particulate materials from uplands across riparian zones and down the channels of river corridors? These papers cover work conducted in small watersheds on a wide range of topics within the spirit and geographical focus area of LBA: water balance and runoff generation, nutrient transformations in riparian zones and stream channels, carbon fluxes in water moving from land to water and the influence of soils on flowpath structure and stream chemistry. Important new insights can be gained from these and other studies. Forest clearing for pastures results in a decrease in soil hydraulic conductivity that forces water into surficial flowpaths throughout most of the rainy season across wide regions of the Amazon. Riparian zones along small forest streams appear to be very effective in removing nitrate arriving from the uplands, while forest streams take up nitrate at very low rates, allowing them to travel downstream for long distances. Although substantial, the contribution of dissolved organic C (DOC) to the carbon flux from forests to streams appears to be lower than the flux of dissolved inorganic C that is subsequently outgassed as CO2. Remaining key challenges within LBA will be to synthesize existing data sets on river networks, soils, climate, land use and planned infrastructure for the Amazon to develop models capable of predicting hydrologic and biogeochemical fluxes at a variety of scales relevant to the development of strategies for sustainable management of the Amazon's remarkable forest, soil and freshwater resources. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{neill_hydrological_2006, author = {Neill, Christopher and Elsenbeer, Helmut and Krusche, Alex V. and Lehmann, Johannes and Markewitz, Daniel and Figueiredo, Ricardo de O.}, title = {Hydrological and biogeochemical processes in a changing Amazon: results from small watershed studies and the large-scale biosphere-atmosphere experiment}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2467--2476}, url = {://WOS:000239670800001}, doi = {https://doi.org/10.1002/hyp.6210} } |
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Neill, C., Deegan, L.A., Thomas, S.M., Haupert, C.L., Krusche, A.V., Ballester, V.M. and Victoria, R.L. | Deforestation alters the hydraulic and biogeochemical characteristics of small lowland Amazonian streams | 2006 | Hydrological Processes Vol. 20(12), pp. 2563-2580 |
article | DOI URL |
Abstract: We investigated how clearing of the tropical rainforest for cattle pasture along small, terra firme lowland streams in the Brazilian Amazon influenced stream hydraulic characteristics, solute concentrations and uptake of dissolved inorganic nitrogen and phosphorus. Measurements of stream channel structure, hydraulic properties and nutrient uptake were obtained from short-term conservative and non-conservative solute injections and an in-stream transport model in two watersheds with pairs of similar-sized forest and pasture streams in Rondonia. The pasture stream channels were deeper and had a lower cover of sandy bottom habitat and a higher cover of aquatic grass habitat than the forest streams. The pasture streams had larger transient storage zones, higher ratios of transient to channel storage and a shorter hydraulic uptake length than the forest streams. The pasture streams had lower concentrations of dissolved oxygen and NO3- and higher concentrations of dissolved Fe2+. Forest streams exhibited no NO3- uptake, but one pasture stream took up NO3- while the other did not. Uptake of NH4+ was low and variable among streams. Uptake velocities and rates Of PO43- were greater in pasture streams compared to those in forest streams. In all streams, uptake lengths for NO3-, NH4+ and PO43- were long and indicated generally lower rates of uptake than in most comparably sized temperate forest streams. Uptake lengths or velocities were not correlated with stream transient storage, suggesting that other factors, such as hypoxia in pasture streams, controlled nutrient uptake. The structural differences are typical for the region, suggesting that deforestation may be altering stream hydrology and biogeochemistry over many thousands of kilometres of primary and secondary stream channels in the Amazon Basin. A better understanding of the extent and distribution of altered hydraulic and biogeochemical function in small streams is required to assess the importance of these changes for larger river networks in the Amazon basin. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{neill_deforestation_2006, author = {Neill, Christopher and Deegan, Linda A. and Thomas, Suzanne M. and Haupert, Christie L. and Krusche, Alex V. and Ballester, Victoria M. and Victoria, Reynaldo L.}, title = {Deforestation alters the hydraulic and biogeochemical characteristics of small lowland Amazonian streams}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2563--2580}, url = {://WOS:000239670800007}, doi = {https://doi.org/10.1002/hyp.6216} } |
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Neill, C., Deegan, L.A., Thomas, S.M. and Cerri, C.C. | Deforestation for pasture alters nitrogen and phosphorus in small Amazonian Streams | 2001 | Ecological Applications Vol. 11(6), pp. 1817-1828 |
article | DOI URL |
Abstract: The clearing of moist, lowland tropical forest for cattle pasture represents a widespread land use change that has consequences for soil biogeochemical cycles, as well as the links between soil processes and the concentrations of dissolved and particulate materials in rivers and streams. We examined how conversion of tropical forest to actively grazed cattle pasture in the Brazilian Amazon influenced the concentrations of different forms of nitrogen (N) and phosphorus (P) in soil solution and stream water. We compared two pairs of watersheds containing second-order streams that drained land in either forest or pasture at Fazenda Nova Vida, a cattle ranch in central Rondonia. Measurements were made during the dry season (low flows) and the wet season (high flows). Forest soil solution had higher NO3- concentrations than pasture, but similar concentrations of NH4+ and PO43- Higher solution NO3- led to higher ratios of dissolved inorganic N:P in forest soils. Pasture streams had higher concentrations of total suspended solids, particulate organic carbon (POC), and particulate organic N (PON) during the dry season, but not during the wet season. Pasture streams also had lower concentrations of NO3- than forest streams. This was consistent with previous studies that found lower extractable NO3- concentrations and lower rates of net N mineralization and net nitrification in the soils of the pasture watersheds compared with forest watersheds. Dissolved organic N (DON) dominated stream water dissolved-N concentrations in forest (53-76%) and pasture (67-84%). Higher dissolved inorganic N (DIN) concentrations in forest streams coupled with a trend toward higher DON and PON concentrations in pastures led to small differences in total N (TN) concentrations between land uses. Lower ratios of inorganic and total dissolved N:P in pasture streams suggested a switch from P limitation in forest streams to N limitation in pasture streams. Periphyton bioassays in forest and pasture streams confirmed that N limited algal growth in pasture streams where light was available. These results suggest that links among deforestation, soil biogeochemistry, and the stoichiometry of N and P reaching streams in small watersheds have the potential to influence the structure of these aquatic ecosystems. | |||||
BibTeX:
@article{neill_deforestation_2001, author = {Neill, C. and Deegan, L. A. and Thomas, S. M. and Cerri, C. C.}, title = {Deforestation for pasture alters nitrogen and phosphorus in small Amazonian Streams}, journal = {Ecological Applications}, year = {2001}, volume = {11}, number = {6}, pages = {1817--1828}, url = {://WOS:000172456700020}, doi = {https://doi.org/10.2307/3061098} } |
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Neill, C., Chaves, J.E., Biggs, T., Deegan, L.A., Elsenbeer, H., Figueiredo, R.O., Germer, S., Johnson, M.S., Lehmann, J., Markewitz, D. and Piccolo, M.C. | Runoff sources and land cover change in the Amazon: an end-member mixing analysis from small watersheds | 2011 | Biogeochemistry Vol. 105(1-3), pp. 7-18 |
article | DOI URL |
Abstract: The flowpaths by which water moves from watersheds to streams has important consequences for the runoff dynamics and biogeochemistry of surface waters in the Amazon Basin. The clearing of Amazon forest to cattle pasture has the potential to change runoff sources to streams by shifting runoff to more surficial flow pathways. We applied end-member mixing analysis (EMMA) to 10 small watersheds throughout the Amazon in which solute composition of streamwater and groundwater, overland flow, soil solution, throughfall and rainwater were measured, largely as part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia. We found a range in the extent to which streamwater samples fell within the mixing space determined by potential flowpath end-members, suggesting that some water sources to streams were not sampled. The contribution of overland flow as a source of stream flow was greater in pasture watersheds than in forest watersheds of comparable size. Increases in overland flow contribution to pasture streams ranged in some cases from 0% in forest to 27-28% in pasture and were broadly consistent with results from hydrometric sampling of Amazon forest and pasture watersheds that indicate 17- to 18-fold increase in the overland flow contribution to stream flow in pastures. In forest, overland flow was an important contribution to stream flow (45-57%) in ephemeral streams where flows were dominated by stormflow. Overland flow contribution to stream flow decreased in importance with increasing watershed area, from 21 to 57% in forest and 60-89% in pasture watersheds of less than 10 ha to 0% in forest and 27-28% in pastures in watersheds greater than 100 ha. Soil solution contributions to stream flow were similar across watershed area and groundwater inputs generally increased in proportion to decreases in overland flow. Application of EMMA across multiple watersheds indicated patterns across gradients of stream size and land cover that were consistent with patterns determined by detailed hydrometric sampling. | |||||
BibTeX:
@article{neill_runoff_2011, author = {Neill, Christopher and Chaves, Joaquin E. and Biggs, Trent and Deegan, Linda A. and Elsenbeer, Helmut and Figueiredo, Ricardo O. and Germer, Sonja and Johnson, Mark S. and Lehmann, Johannes and Markewitz, Daniel and Piccolo, Marisa C.}, title = {Runoff sources and land cover change in the Amazon: an end-member mixing analysis from small watersheds}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {7--18}, url = {://WOS:000294501100002}, doi = {https://doi.org/10.1007/s10533-011-9597-8} } |
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Negrón-Juárez, R.I., Jenkins, H.S., Raupp, C.F.M., Riley, W.J., Kueppers, L.M., Marra, D.M., Ribeiro, G.H.P.M., Monteiro, M.T.F., Candido, L.A., Chambers, J.Q. and Higuchi, N. | Windthrow Variability in Central Amazonia [BibTeX] |
2017 | Atmosphere Vol. 8(28) |
article | DOI |
BibTeX:
@article{negron-juarez_windthrow_2017, author = {Negrón-Juárez, Robinson I. and Jenkins, Hillary S. and Raupp, Carlos F. M. and Riley, William J. and Kueppers, Lara M. and Marra, Daniel Magnabosco and Ribeiro, Gabriel H. P. M. and Monteiro, Maria Terezinha F. and Candido, Luis A. and Chambers, Jeffrey Q. and Higuchi, Niro}, title = {Windthrow Variability in Central Amazonia}, journal = {Atmosphere}, year = {2017}, volume = {8}, number = {28}, doi = {https://doi.org/10.3390/atmos8020028} } |
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Negrón-Juárez, R.I., Holm, J.A., Faybishenko, B., Magnabosco-Marra, D., Fisher, R.A., Shuman, J.K., de Araujo, A.C., Riley, W.J. and Chambers, J.Q. | Landsat near-infrared (NIR) band and ELM-FATES sensitivity to forest disturbances and regrowth in the Central Amazon [BibTeX] |
2020 | Biogeosciences Vol. 17(23), pp. 6185-6205 |
article | DOI URL |
BibTeX:
@article{negron-juarez_landsat_2020, author = {Negrón-Juárez, R. I. and Holm, J. A. and Faybishenko, B. and Magnabosco-Marra, D. and Fisher, R. A. and Shuman, J. K. and de Araujo, A. C. and Riley, W. J. and Chambers, J. Q.}, title = {Landsat near-infrared (NIR) band and ELM-FATES sensitivity to forest disturbances and regrowth in the Central Amazon}, journal = {Biogeosciences}, year = {2020}, volume = {17}, number = {23}, pages = {6185--6205}, url = {https://bg.copernicus.org/articles/17/6185/2020/}, doi = {https://doi.org/10.5194/bg-17-6185-2020} } |
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Negrón-Juárez, R., Chambers, J., Marra, D., Ribeiro, G., Rifai, S., Higuchi, N. and Roberts, D. | Detection of subpixel treefall gaps with Landsat imagery in Central Amazon forests [BibTeX] |
2011 | Remote Sensing of Environment Vol. 115, pp. 3322-3328 |
article | |
BibTeX:
@article{negron-juarez_detection_2011, author = {Negrón-Juárez, R.I. and Chambers, J.Q. and Marra, D.M. and Ribeiro, G.H.P.M. and Rifai, S.W. and Higuchi, N. and Roberts, D.}, title = {Detection of subpixel treefall gaps with Landsat imagery in Central Amazon forests}, journal = {Remote Sensing of Environment}, year = {2011}, volume = {115}, pages = {3322--3328} } |
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Negron-Juarez, R.I., Chambers, J.Q., Guimaraes, G., Zeng, H., Raupp, C.F.M., Marra, D.M., Ribeiro, G.H.P.M., Saatchi, S.S., Nelson, B.W. and Higuchi, N. | Widespread Amazon forest tree mortality from a single cross-basin squall line event | 2010 | Geophysical Research Letters Vol. 37 |
article | DOI URL |
Abstract: Climate change is expected to increase the intensity of extreme precipitation events in Amazonia that in turn might produce more forest blowdowns associated with convective storms. Yet quantitative tree mortality associated with convective storms has never been reported across Amazonia, representing an important additional source of carbon to the atmosphere. Here we demonstrate that a single squall line (aligned cluster of convective storm cells) propagating across Amazonia in January, 2005, caused widespread forest tree mortality and may have contributed to the elevated mortality observed that year. Forest plot data demonstrated that the same year represented the second highest mortality rate over a 15-year annual monitoring interval. Over the Manaus region, disturbed forest patches generated by the squall followed a power-law distribution (scaling exponent alpha = 1.48) and produced a mortality of 0.3-0.5 million trees, equivalent to 30% of the observed annual deforestation reported in 2005 over the same area. Basin-wide, potential tree mortality from this one event was estimated at 542 +/- 121 million trees, equivalent to 23% of the mean annual biomass accumulation estimated for these forests. Our results highlight the vulnerability of Amazon trees to wind-driven mortality associated with convective storms. Storm intensity is expected to increase with a warming climate, which would result in additional tree mortality and carbon release to the atmosphere, with the potential to further warm the climate system. Citation: Negron-Juarez, R. I., J. Q. Chambers, G. Guimaraes, H. Zeng, C. F. M. Raupp, D. M. Marra, G. H. P. M. Ribeiro, S. S. Saatchi, B. W. Nelson, and N. Higuchi (2010), Widespread Amazon forest tree mortality from a single cross-basin squall line event, Geophys. Res. Lett., 37, L16701, doi:10.1029/2010GL043733. | |||||
BibTeX:
@article{negron-juarez_widespread_2010, author = {Negron-Juarez, Robinson I. and Chambers, Jeffrey Q. and Guimaraes, Giuliano and Zeng, Hongcheng and Raupp, Carlos F. M. and Marra, Daniel M. and Ribeiro, Gabriel H. P. M. and Saatchi, Sassan S. and Nelson, Bruce W. and Higuchi, Niro}, title = {Widespread Amazon forest tree mortality from a single cross-basin squall line event}, journal = {Geophysical Research Letters}, year = {2010}, volume = {37}, url = {://WOS:000281138000001}, doi = {https://doi.org/10.1029/2010gl043733} } |
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Negron-Juarez, R., Magnabosco-Marra, D., Feng, Y., Urquiza-Muñoz, J.D., Riley, W.J. and Chambers, J.Q. | Windthrow characteristics and their regional association with rainfall, soil, and surface elevation in the Amazon [BibTeX] |
2023 | Environmental Research Letters Vol. 18(1), pp. 014030 |
article | DOI URL |
BibTeX:
@article{negron-juarez_windthrow_2023, author = {Negron-Juarez, Robinson and Magnabosco-Marra, Daniel and Feng, Yanlei and Urquiza-Muñoz, Jose David and Riley, William J. and Chambers, Jeffrey Q.}, title = {Windthrow characteristics and their regional association with rainfall, soil, and surface elevation in the Amazon}, journal = {Environmental Research Letters}, year = {2023}, volume = {18}, number = {1}, pages = {014030}, url = {https://dx.doi.org/10.1088/1748-9326/acaf10}, doi = {https://doi.org/10.1088/1748-9326/acaf10} } |
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Negrón-Juárez, R., Ferreira, S.J.F., Mota, M.C., Faybishenko, B., Monteiro, M.T.F., Candido, L.A., Ribeiro, R.P., de Oliveira, R.C., de Araujo, A.C., Warren, J.M., Newman, B.D., Gimenez, B.O., Varadharajan, C., Agarwal, D., Borma, L., Tomasella, J., Higuchi, N. and Chambers, J.Q. | Calibration, measurement, and characterization of soil moisture dynamics in a central Amazonian tropical forest | 2020 | Vadose Zone Journal Vol. 19(1), pp. e20070 |
article | DOI URL |
Abstract: Abstract Soil moisture plays a key role in hydrological, biogeochemical, and energy budgets of terrestrial ecosystems. Accurate soil moisture measurements in remote ecosystems such as the Amazon are difficult and limited because of logistical constraints. Time domain reflectometry (TDR) sensors are widely used to monitor soil moisture and require calibration to convert the TDR's dielectric permittivity measurement (Ka) to volumetric water content (θv). In this study, our objectives were to develop a field-based calibration of TDR sensors in an old-growth upland forest in the central Amazon, to evaluate the performance of the calibration, and then to apply the calibration to determine the dynamics of soil moisture content within a 14.2-m-deep vertical soil profile. Depth-specific TDR calibration using local soils in a controlled laboratory setting yielded a novel Ka–θv third-degree polynomial calibration. The sensors were later installed to their specific calibration depth in a 14.2-m pit. The widely used Ka–θv relationship (Topp model) underestimated the site-specific θv by 22–42%, indicating significant error in the model when applied to these well-structured, clay-rich tropical forest soils. The calibrated wet- and dry-season θv data showed a variety of depth and temporal variations highlighting the importance of soil textural differentiation, root uptake depths, as well as event to seasonal precipitation effects. Data such as these are greatly needed for improving our understanding of ecohydrological processes within tropical forests and for improving models of these systems in the face of changing environmental conditions. | |||||
BibTeX:
@article{negron-juarez_calibration_2020, author = {Negrón-Juárez, Robinson and Ferreira, Savio J. F. and Mota, Marcelo Crestani and Faybishenko, Boris and Monteiro, Maria Terezinha F. and Candido, Luiz A. and Ribeiro, Rubia Pereira and de Oliveira, Regison Costa and de Araujo, Alessandro C. and Warren, Jeffrey M. and Newman, Brent D. and Gimenez, Bruno O. and Varadharajan, Charuleka and Agarwal, Deborah and Borma, Laura and Tomasella, Javier and Higuchi, Niro and Chambers, Jeffrey Q.}, title = {Calibration, measurement, and characterization of soil moisture dynamics in a central Amazonian tropical forest}, journal = {Vadose Zone Journal}, year = {2020}, volume = {19}, number = {1}, pages = {e20070}, url = {https://acsess.onlinelibrary.wiley.com/doi/abs/10.1002/vzj2.20070}, doi = {https://doi.org/10.1002/vzj2.20070} } |
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Negrón-Juárez, R., Baker, D., Chambers, J., Hurtt, G. and Goosem, S. | Multi-scale sensitivity of Landsat and MODIS to forest disturbance associated with tropical cyclones [BibTeX] |
2014 | Remote Sensing of Environment Vol. 140, pp. 679-689 |
article | |
BibTeX:
@article{negron-juarez_multi-scale_2014, author = {Negrón-Juárez, R. and Baker, D.B. and Chambers, J.Q. and Hurtt, G.C. and Goosem, S.}, title = {Multi-scale sensitivity of Landsat and MODIS to forest disturbance associated with tropical cyclones}, journal = {Remote Sensing of Environment}, year = {2014}, volume = {140}, pages = {679--689} } |
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Negron Juarez, R.I., Hodnett, M.G., Fu, R., Goulden, M.L. and von Randow, C. | Control of dry season evapotranspiration over the Amazonian forest as inferred from observations at a southern Amazon forest site | 2007 | Journal of Climate Vol. 20(12), pp. 2827-2839 |
article | DOI URL |
Abstract: The extent to which soil water storage can support an average dry season evapotranspiration ( ET) is investigated using observations from the Rebio Jaru site for the period of 2000 to 2002. During the dry season, when total rainfall is less than 100 mm, the soil moisture storage available to root uptake in the top 3- m layer is sufficient to maintain the ET rate, which is equal to or higher than that in the wet season. With a normal or less- than- normal dry season rainfall, more than 75% of the ET is supplied by soil water below 1 m, whereas during a rainier dry season, about 50% of ET is provided by soil water from below 1 m. Soil moisture below 1- m depth is recharged by rainfall during the previous wet season: dry season rainfall rarely infiltrates to this depth. These results suggest that, even near the southern edge of the Amazon forest, seasonal and moderate interannual rainfall deficits can be mitigated by an increase in root uptake from deeper soil. How dry season ET varies geographically within the Amazon and what might control its geographic distribution are examined by comparing in situ observations from 10 sites from different areas of Amazonia reported during the last two decades. Results show that the average dry season ET varies less than 1 mm day(-1) or 30% from the driest to nearly the wettest parts of Amazonia and is largely correlated with the change of surface net radiation of 25% and 30%. Thus the geographic variation of the average dry season ET appears to be mainly determined by the surface radiation. | |||||
BibTeX:
@article{negron_juarez_control_2007, author = {Negron Juarez, Robinson I. and Hodnett, Martin G. and Fu, Rong and Goulden, Michael L. and von Randow, Celso}, title = {Control of dry season evapotranspiration over the Amazonian forest as inferred from observations at a southern Amazon forest site}, journal = {Journal of Climate}, year = {2007}, volume = {20}, number = {12}, pages = {2827--2839}, url = {://WOS:000247363100006}, doi = {https://doi.org/10.1175/jcli4184.1} } |
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Negri, A.J., Anagnostou, E.N. and Adler, R.F. | A 10-yr climatology of Amazonian rainfall derived from passive microwave satellite observations | 2000 | Journal of Applied Meteorology Vol. 39(1), pp. 42-56 |
article | DOI URL |
Abstract: In this study, a satellite-derived precipitation "climatology" (climate description) over northern South America using a passive microwave technique, the Goddard Profiling algorithm, is presented. The results are statistically adjusted to have the same probability distribution as a rain gauge dataset. The climatologies take the form of the mean estimated rainfall for a 10-yr+ period with subdivisions by month and meteorological season. For the 6-yr period 1992-97, when two satellites were in operation, diurnal variability (to the extent it is discerned by four unequally spaced observations) is presented. In the mean, dramatic patterns of alternating morning and evening maxima are seen stretching from the northeast (Atlantic coast) across the continent to the Pacific. The effects of local circulations caused by topography, coastlines, and geography (river valleys) on the rainfall patterns are evident, particularly in the region around Manaus, Brazil, where the Negro and Solimoes Rivers merge. The interannual variability of the IO-yr rainfall estimate is examined by computing the deviations of yearly and warm-season (December-February) rainfall from their respective long-term means. Rainfall anomalies associated with Fl Nino and La Nina events then become apparent. This gauge-adjusted satellite climatology enhances existing (gauge based) climatologies by increasing the spatial resolution and providing a common, spaceborne platform for assessing interannual variability. It maintains the same first- and second-order statistics as does the gauge dataset, and allows a first attempt at examining the diurnal cycles by utilizing passive microwave observations (up to) four times per day. | |||||
BibTeX:
@article{negri_10-yr_2000, author = {Negri, A. J. and Anagnostou, E. N. and Adler, R. F.}, title = {A 10-yr climatology of Amazonian rainfall derived from passive microwave satellite observations}, journal = {Journal of Applied Meteorology}, year = {2000}, volume = {39}, number = {1}, pages = {42--56}, url = {://WOS:000085124900003 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0450%282000%29039%3C0042%3AAYCOAR%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0450(2000)039%3C0042:aycoar%3E2.0.co;2} } |
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Negri, A.J., Adler, R.F., Xu, L.M. and Surratt, J. | The impact of Amazonian deforestation on dry season rainfall | 2004 | Journal of Climate Vol. 17(6), pp. 1306-1319 |
article | DOI URL |
Abstract: Many modeling studies have concluded that widespread deforestation of Amazonia would lead to decreased rainfall. Geosynchronous visible and infrared satellite data over southwest Brazil are analyzed with respect to percent cloudiness, and rain estimates are analyzed from both the Tropical Rainfall Measuring Mission and Special Sensor Microwave Imager. The studies conclude that in the dry season, when the effects of the surface are not overwhelmed by synoptic-scale weather disturbances, shallow cumulus cloudiness, deep convective cloudiness, and rainfall occurrence all are larger over the deforested and nonforested (savanna) regions than over areas of dense forest. This paper speculates that this difference is in response to a local circulation initiated by the differential heating of the region's varying forestation. Analysis of the diurnal cycle of cloudiness reveals a shift in the onset of convection toward afternoon hours in the deforested and toward the morning hours in the savanna regions when compared to the neighboring forested regions. Analysis of 14 years of monthly estimates from the Special Sensor Microwave Imager data revealed that in August there was a pattern of higher monthly rainfall amounts over the deforested region. Analysis of available rain gauge data showed an increase in regional rainfall since deforestation began around 1978. | |||||
BibTeX:
@article{negri_impact_2004, author = {Negri, A. J. and Adler, R. F. and Xu, L. M. and Surratt, J.}, title = {The impact of Amazonian deforestation on dry season rainfall}, journal = {Journal of Climate}, year = {2004}, volume = {17}, number = {6}, pages = {1306--1319}, url = {://WOS:000220450100013}, doi = {https://doi.org/10.1175/1520-0442(2004)017%3C1306:tioado%3E2.0.co;2} } |
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Negri, A.J., Adler, R.F. and Xu, L. | A TRMM-calibrated infrared rainfall algorithm applied over Brazil | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] The development of a satellite infrared technique for estimating convective and stratiform rainfall and its application in studying the diurnal variability of rainfall in Amazonia are presented. The convective-stratiform technique (CST), calibrated by coincident, physically retrieved rain rates from the TRMM microwave imager (TMI), is applied during January-April 1999 over northern South America. The diurnal cycle of rainfall, as well as the division between convective and stratiform rainfall, is presented. Results compare well (a 1-hour lag) with the diurnal cycle derived from TOGA radar-estimated rainfall in Rondonia. The satellite estimates reveal that the convective rain constitutes, in the mean, 24% of the rain area while accounting for 67% of the rain volume. Estimates of the diurnal cycle for the entire Amazon Basin are in agreement with those from the TRMM precipitation radar, despite the limited sampling of the latter. The effects of geography (rivers, lakes, coasts) and topography on the diurnal cycle of convection are examined. In particular, the Amazon River, downstream of Manaus, is shown to both enhance early morning rainfall and inhibit afternoon convection. Monthly estimates from this technique, dubbed CST/TMI, are verified over a dense rain gage network in the state of Ceara, in northeast Brazil. The CST/TMI showed a high bias equal to +33% of the gage mean, indicating that possibly the TMI estimates alone are also high. The root-mean-square difference (after removal of the bias) equaled 36.6% of the gage mean. The correlation coefficient was 0.77 based on 72 station months. | |||||
BibTeX:
@article{negri_trmm-calibrated_2002, author = {Negri, A. J. and Adler, R. F. and Xu, L.}, title = {A TRMM-calibrated infrared rainfall algorithm applied over Brazil}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200005}, doi = {https://doi.org/10.1029/2000jd000265} } |
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Neeff, T., Lucas, R.M., dos Santos, J.R., Brondizio, E.S. and Freitas, C.C. | Area and age of secondary forests in Brazilian Amazonia 1978-2002: An empirical estimate | 2006 | Ecosystems Vol. 9(4), pp. 609-623 |
article | DOI URL |
Abstract: In quantifying the carbon budget of the Amazon region, temporal estimates of the extent and age of regenerating tropical forests are fundamental. However, retrieving such information from remote-sensing data is difficult, largely because of spectral similarities between different successional stages and variations in the reflectance of forests following different pathways of regeneration. In this study, secondary-forest dynamics in Brazilian Amazonia were modeled for the 1978-2002 period to determine area and age on a grid basis. We modeled the area, age, and age class distribution of secondary forests using empirical relationships with the percentage of remaining primary forest, as determined from large-area remote-sensing campaigns (the Pathfinder and Prodes projects). The statistical models were calibrated using detailed maps of secondary-forest age generated for seven sites in the Brazilian Legal Amazon. The area-age distribution was then specified from mean age by a distribution assumption. Over the period 1978-2002, secondary-forest area was shown to have increased from 29,000 to 161,000 km(2) (that is, by a factor of 5). The mean age increased from 4.4 to 4.8 years. We generated a time series of secondary-forest area fractions and successional stages that provides wall-to-wall coverage of the Brazilian Amazon at a spatial resolution of 0.1 decimal degrees (approximately 11 km). Validation against reference data yielded root mean squared errors of 8% of the total area for estimate of secondary-forest area and 2.4 years for mean secondary-forest age. Using this approach, we provide the first published update on the state of secondary forests in Amazonia since the early 1990s and a time series of secondary-forest area over the 25-year period. | |||||
BibTeX:
@article{neeff_area_2006, author = {Neeff, T. and Lucas, R. M. and dos Santos, J. R. and Brondizio, E. S. and Freitas, C. C.}, title = {Area and age of secondary forests in Brazilian Amazonia 1978-2002: An empirical estimate}, journal = {Ecosystems}, year = {2006}, volume = {9}, number = {4}, pages = {609--623}, url = {://WOS:000238292700009 http://www.springerlink.com/content/l8473j520u66508k/fulltext.pdf}, doi = {https://doi.org/10.1007/s10021-006-0001-9} } |
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Neeff, T., Graca, P.M.D., Dutra, L.V. and Freitas, C.D. | Carbon budget estimation in Central Amazonia: Successional forest modeling from remote sensing data | 2005 | Remote Sensing of Environment Vol. 94(4), pp. 508-522 |
article | DOI URL |
Abstract: The carbon budget resulting from the dynamics of forest vegetation was estimated spatially for a study region with intensive land use change in the Central Amazonia forest. Vegetation height was recovered from airborne SAR interferometry, and was used along with an established relationship between forest height and age for mapping the successional stages of vegetation. A map of forest ages could be generated and validated (age RMSE was 3.5 years). Biomass stocks and annual rates of increment in biomass could be attributed to the forest ages by a comprehensive growth model for forests in the study area. A conceptual model of land use change was developed for the study area that accounts for four different types of land use: primary forest, secondary forest, degraded forest and nonforest. The transition probabilities between those land use types were recovered from internal modeling of available data, from literature sources, and from large-scale remote sensing results. The land use change matrix, area-age densities of secondary forests, and a growth model, yield a spatialized estimate of the carbon budget. The committed emissions from annual land use change were computed. For the year 2000-2001 the carbon balance was negative, on an area of ca. 5700 ha, land use dynamics resulted in a release of approximately 16,000 t of carbon, mainly arising from the cutting of primary forest for agricultural purposes. The secondary forest carbon budget was almost balanced, and forest degradation was revealed less important. (C) 2004 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{neeff_carbon_2005, author = {Neeff, T. and Graca, P. M. D. and Dutra, L. V. and Freitas, C. D.}, title = {Carbon budget estimation in Central Amazonia: Successional forest modeling from remote sensing data}, journal = {Remote Sensing of Environment}, year = {2005}, volume = {94}, number = {4}, pages = {508--522}, url = {://WOS:000227046700007}, doi = {https://doi.org/10.1016/j.rse.2004.12.002} } |
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Neeff, T., Dutra, L.V., dos Santos, J.R., Freitas, C.D. and Araujo, L.S. | Tropical forest measurement by interferometric height modeling and P-band radar backscatter | 2005 | Forest Science Vol. 51(6), pp. 585-594 |
article | URL |
Abstract: A new approach to tropical forest biomass monitoring with airborne interferometric X and P-band synthetic aperture radar (SAR) data is presented. Forest height, basal area, and aboveground biomass are modeled from remote sensing, data for a study site in the Brazilian Amazon. Radar data quality has improved: A novel digital model of vegetation height from X- and P-band interferometry is available along with the usual P-band backscatter information. The digital vegetation height model is derived from the interferometric surface models of the ground (from P-band) and the forest canopy (from X-band). The difference between the surface models is called "interferometric height," and is used as a measure of vegetation height. Interferometric height is shown to relate to a subset of the forest trees that changes according to the forest successional stages. The suitability of radar backscatter and interferometric height as a means for forest and biomass monitoring was explored by relating forest parameters as measured in the field to remote sensing data. Basal area and biomass were related to radar backscatter with limited precision of r(2) = 0.19 and r(2) = 0.34, respectively. Mean forest height is shown to relate to interferometric height with good precision (r(2) = 0.83, RMSE = 4.1 m). A statistical model for forest biomass as a function of both P-band backscatter and interferometric height information not only arrives at high values of precision (with r(2) = 0.89 and a RMSE from cross-validation of only 46.1 t/ha), but also overcomes the well-known issue of backscatter saturation. This research shows that tropical forest biomass can be quantified and mapped over large areas for a range of forest structures with reasonably tight and similar errors. | |||||
BibTeX:
@article{neeff_tropical_2005, author = {Neeff, T. and Dutra, L. V. and dos Santos, J. R. and Freitas, C. D. and Araujo, L. S.}, title = {Tropical forest measurement by interferometric height modeling and P-band radar backscatter}, journal = {Forest Science}, year = {2005}, volume = {51}, number = {6}, pages = {585--594}, url = {://WOS:000233973800009} } |
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Neeff, T., Dutra, L.V., dos Santos, J.R., Freitas, C.D. and Araujo, L.S. | Tropical forest stand table modelling from SAR data | 2003 | Forest Ecology and Management Vol. 186(1-3), pp. 159-170 |
article | DOI URL |
Abstract: Diameter distributions of forest stands are modelled by the three-parameter Weibull distribution for a variety of different forest types in the Brazilian Amazon. The parameters of the function are arrived at by estimation: (1) only from tree diameters as measured in the field, and (2) only from backscatter coefficients and interferometric height measurements as obtained from airborne synthetic aperture radar. The models yield good results of fit, the modelling of forest structure, i.e. of the stand tables, is equally precise from ground data as from remote sensing data. The adopted approach provides a convincing basis for the monitoring of forest structure over huge areas at low cost by adding a new feature to the analysis of high precision SAR data. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{neeff_tropical_2003, author = {Neeff, T. and Dutra, L. V. and dos Santos, J. R. and Freitas, C. D. and Araujo, L. S.}, title = {Tropical forest stand table modelling from SAR data}, journal = {Forest Ecology and Management}, year = {2003}, volume = {186}, number = {1-3}, pages = {159--170}, url = {://WOS:000186868100013}, doi = {https://doi.org/10.1016/s0378-1127(03)00234-2} } |
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Neeff, T., Dutra, L.V., Dos Santos, J.R., Freitas, C.C. and Araujo, L.S. | Power spectrum analysis of SAR data for spatial forest characterization in Amazonia | 2005 | International Journal of Remote Sensing Vol. 26(13), pp. 2851-2864 |
article | DOI URL |
Abstract: Power spectrum analysis was used for the analysis of spatial forest features from airborne X-band synthetic aperture radar (SAR) data in the Brazilian Amazon. Spectral estimates were arrived at empirically by periodograms and correlograms, and from autoregressive moving-average (ARMA) models. The spectral estimates derived from SAR data were validated by those derived from ground data with locational match. The results obtained by ARMA modelling revealed particularly good correspondence between remote sensing and reference data: repeating patterns at pixel level could be detected in the images. These patterns were shown to arise from canopy structure and distances between major tree individuals; and thus allowed the extraction of parameters of spatial forest structure, particularly of forest density. The method was applied to an example area of primary tropical forest, and its spatial patterns were modelled. | |||||
BibTeX:
@article{neeff_power_2005, author = {Neeff, T. and Dutra, L. V. and Dos Santos, J. R. and Freitas, C. C. and Araujo, L. S.}, title = {Power spectrum analysis of SAR data for spatial forest characterization in Amazonia}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {13}, pages = {2851--2864}, url = {://WOS:000230757900010}, doi = {https://doi.org/10.1080/01431160500104301} } |
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Neeff, T. and dos Santos, J.R. | A growth model for secondary forest in Central Amazonia | 2005 | Forest Ecology and Management Vol. 216(1-3), pp. 270-282 |
article | DOI URL |
Abstract: A comprehensive stand level growth model for secondary forest in the Central Amazon is presented. The model has been established for a study site in the Tapajos region for secondary forest of an age up to ca. 35 years. The Bertalanffy-Chapman-Richards equation is applied in a state space approach: a set of differential equations is fitted by nonlinear least-squares to observed stand level growth data in top height, tree density and basal area. Other forest variables are derived by auxiliary relationships to the state variables. The observed growth patterns are first modeled, and then discussed. All fitted coefficients of the growth and increment functions are provided along with a growth table. This study counts with a usual data record for Central Amazonia and presents the first comprehensive growth model for secondary forests in the region. The results are basic data on forest growth and its patterns that are of utmost importance in many ecological contexts. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{neeff_growth_2005, author = {Neeff, T. and dos Santos, J. R.}, title = {A growth model for secondary forest in Central Amazonia}, journal = {Forest Ecology and Management}, year = {2005}, volume = {216}, number = {1-3}, pages = {270--282}, url = {://WOS:000233742400021}, doi = {https://doi.org/10.1016/j.foreco.2005.05.039} } |
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Neeff, T., Biging, G.S., Dutra, L.V., Freitas, C.C. and dos Santos, J.R. | Markov point processes for modeling of spatial forest patterns in Amazonia derived from interferometric height | 2005 | Remote Sensing of Environment Vol. 97(4), pp. 484-494 |
article | DOI URL |
Abstract: The spatial distribution of very large trees in primary Amazon forest is studied with an indicative data set. Very large trees with height larger than 30 in are shown to be highly influential on forest structure, ecology and biomass regime. In particular, they account for a large portion of total above-ground biomass. Their spatial patterns are extracted from airborne SAR data, namely from a digital model- of interferometric forest height, by an approach of local maximum filtering. The spatial point patterns describing the distribution of very large trees in the forest within three sample blocks of 100 ha each are modeled by a series of Markov point process models. These models are fitted and assessed by standard spatial statistical methodology. Spatial distribution is regular, and interaction decreases with distance; very large trees are shown to exert repulsive interaction with their neighboring very large trees. The significance of these results for approaches of quantitative forest assessment in primary forests in the Brazilian Amazon is discussed. (C) 2005 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{neeff_markov_2005, author = {Neeff, T. and Biging, G. S. and Dutra, L. V. and Freitas, C. C. and dos Santos, J. R.}, title = {Markov point processes for modeling of spatial forest patterns in Amazonia derived from interferometric height}, journal = {Remote Sensing of Environment}, year = {2005}, volume = {97}, number = {4}, pages = {484--494}, url = {://WOS:000231967800006}, doi = {https://doi.org/10.1016/j.rse.2005.05.019} } |
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Neeff, T. | Deforestation biomass and carbon finance in Amazonia | 2008 | Climate Policy Vol. 8(1), pp. 7-22 |
article | DOI URL |
Abstract: Biomass dynamics in Amazonia are quantified and the value that carbon finance could deliver from slowing deforestation is assessed. Above-ground forest biomass in the Legal Amazon shrank from 90 Pg to 76 Pg between 1978 and 2004. An average decrease of 0.64 Pg (standard error 0.38 Pg) per year was estimated for primary and econdary vegetation. For an improved, spatially and temporally explicit estimation, a time series of remote-sensing results and a model of secondary forest area and age distribution was combined with a large-scale forest-growth model. The observed trend of biomass decline is continuous and defines a baseline that the avoidance of deforestation could be measured against. Based on scenario calculations, the emission reductions from slightly reduced deforestation rates could be valued in the range of El billion annually. Carbon finance for reducing emissions from deforestation ('avoided deforestation'), which is being discussed as an additional mechanism under the UN Framework Convention on Climate Change and its Kyoto Protocol, has the potential to alter the economic logic driving forest conversion. | |||||
BibTeX:
@article{neeff_deforestation_2008, author = {Neeff, T.}, title = {Deforestation biomass and carbon finance in Amazonia}, journal = {Climate Policy}, year = {2008}, volume = {8}, number = {1}, pages = {7--22}, url = {://WOS:000254484000002}, doi = {https://doi.org/10.3763/cpol.2007.0355} } |
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Neeff, T. | Spatial modeling of primary and secondary forest growth in Amazonia | 2005 | Forest Ecology and Management Vol. 219(2-3), pp. 149-168 |
article | DOI URL |
Abstract: A stand level growth model for primary and secondary forest in the Amazon region is presented. The approach is empirical and relies on an extended amount of forest inventory data for model calibration. We used a total of 368 sample plots with 469 ha from primary forest and 330 sample plots with 30.8 ha from secondary forest. The data come from eight countries and are distributed over tropical forests in all of Amazonia. We interpolated primary forest descriptors spatially in virtue of their dependence on biophysical conditions. Secondary forest parameters were described by a set of differential equations, in which the primary forest functioned as asymptotes of the growth processes. A state-space approach to growth modeling allowed for derivation of other forest parameters from models for state variables by auxiliary relationships. The fitted models offer a spatially explicit description of growth and increment over all the tropical forests in Amazonia on a large scale. As a function of biophysiology and of forest age, the models specify individual secondary forest growth curves at the level of grid cells. We calculated grids for forest parameters and their increments in primary and secondary forests of various ages. In primary forest, total basal area ranged between 22 and 33 m(2) ha(-1), top height was 10-35 m, there were 400-850 individuals per hectare, and standing alive above-ground biomass ranged between 110 and 370 t ha-1. The biomass model was validated by comparing predictions at various successional stages from different locations in Amazonia against independent reference data. Despite a small negative bias, the RMSE for standing alive above-ground biomass amounted to only 38 t ha(-1). (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{neeff_spatial_2005, author = {Neeff, T.}, title = {Spatial modeling of primary and secondary forest growth in Amazonia}, journal = {Forest Ecology and Management}, year = {2005}, volume = {219}, number = {2-3}, pages = {149--168}, url = {://WOS:000234166100003}, doi = {https://doi.org/10.1016/j.foreco.2005.08.037} } |
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Nascimento, M.T., Carvalho, L.C.d.S., Barbosa, R.I. and Villela, D.M. | Variation in floristic composition, demography and above-ground biomass over a 20-year period in an Amazonian monodominant forest [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 293-303 |
article | |
BibTeX:
@article{nascimento_variation_2014, author = {Nascimento, Marcelo T. and Carvalho, Lidiany C. da Silva and Barbosa, Reinaldo I. and Villela, Dora M.}, title = {Variation in floristic composition, demography and above-ground biomass over a 20-year period in an Amazonian monodominant forest}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {293--303} } |
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Nascimento, J.S.M.d., Aguiar, R.G., Fischer, G.R., Andrade, N.L.R.d., Aguiar, L.J.G. and Webler, A.D. | Mudanças no Uso da Terra na Amazônia Ocidental e a Resposta do Microclima à Ocorrência de Eventos Extremos | 2020 | Revista Brasileira de Meteorologia Vol. 35(1), pp. 135-145 |
article | DOI URL |
Abstract: The reports of the Intergovernmental Panel on Climate Change constantly reveal the possibility that climatic extremes will increase in the coming years. The Amazon Region has experienced these events frequently, which has contributed to the fact that more studies about its susceptibility are carried out. This study aimed to identify the microclimate response to droughts of 2005 and 2010 in areas of native forest and pasture in the Western Amazon by analyzing specific air humidity, air temperature and net radiation. The data used come from towers belonging to Large Scale Biosphere-Atmosphere Experiment in Amazonia. The results indicate that in the years studied there were significant changes in the variables studied at both sites, with reductions of approximately 16% in specific humidity and increases of up to 3.76% in temperature. However, the effects of the 2010 drought may have been softened in the forest due to the event being preceded by an extreme flood event (2009). The results show that the conversion of forest areas to pasture, together with extreme events, can interfere in the meteorological variables, being necessary the continuous study of this dynamics for the microclimatic implications to be elucidated. Resumo Os relatórios do Painel Intergovernamental Sobre Mudanças Climáticas constantemente divulgam a possibilidade de que a ocorrência de extremos climáticos seja maior nos próximos anos. A Região Amazônica tem experimentado esses eventos com frequência, o que tem contribuído para que mais estudos acerca de sua susceptibilidade sejam realizados. Esse estudo objetivou identificar a resposta do microclima às secas de 2005 e 2010 em áreas de floresta nativa e de pastagem na Amazônia Ocidental por meio da análise da umidade específica do ar, temperatura do ar e saldo de radiação. Os dados utilizados são provenientes de torres pertencentes ao Programa de Grande Escala da Biosfera-Atmosfera na Amazônia. Os resultados indicam que nos anos estudados houveram alterações significativas nas variáveis estudadas em ambos os sítios, com reduções de aproximadamente 16% na umidade específica e aumentos de até 3,76% na temperatura. Entretanto, os efeitos da seca de 2010 podem ter sido amenizados na floresta devido ao evento ser precedido por um evento extremo de cheia (2009). Os resultados evidenciam o quanto a conversão de áreas de floresta para pastagem, aliado aos eventos extremos, pode interferir nas variáveis meteorológicas, sendo imprescindível o contínuo estudo dessa dinâmica para que as implicações microclimáticas sejam elucidadas. |
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BibTeX:
@article{nascimento_mudancas_2020, author = {Nascimento, Jayne Soares Martins do and Aguiar, Renata Gonçalves and Fischer, Graciela Redies and Andrade, Nara Luísa Reis de and Aguiar, Leonardo José Gonçalves and Webler, Alberto Dresch}, title = {Mudanças no Uso da Terra na Amazônia Ocidental e a Resposta do Microclima à Ocorrência de Eventos Extremos}, journal = {Revista Brasileira de Meteorologia}, year = {2020}, volume = {35}, number = {1}, pages = {135--145}, url = {http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-77862020000100135&lang=pt}, doi = {https://doi.org/10.1590/0102-7786351009} } |
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Nascimento, J.S.M., Aguiar, R.G., Webler, A.D., Fischer, G.R., Aguiar, L.J.G. and Ruezzene, C.B. | Variáveis Meteorológicas em Áreas de Floresta e Pastagem na Amazônia Ocidental em Anos de Eventos Extremos [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 217-224 |
article | |
BibTeX:
@article{nascimento_variaveis_2016, author = {Nascimento, J. S. M. and Aguiar, R. G. and Webler, A. D. and Fischer, G. R. and Aguiar, Leonardo J G. and Ruezzene, C. B}, title = {Variáveis Meteorológicas em Áreas de Floresta e Pastagem na Amazônia Ocidental em Anos de Eventos Extremos}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {217--224} } |
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Nascimento, J.S.M., Aguiar, R., Fischer, G.R., Webler, A.D. and Aguiar, .J.G.L. | Características do Microclima em Áreas de Floresta e Pastagem na Região Amazônica em Anos de Eventos Extremos. [BibTeX] |
2018 | Vol. 1(1)Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental, pp. 107-117 |
incollection | |
BibTeX:
@incollection{org_caracteristicas_2018, author = {Nascimento, J. S. M. and Aguiar, R.G. and Fischer, G. R. and Webler, A. D. ; and Aguiar, .J G. L.}, title = {Características do Microclima em Áreas de Floresta e Pastagem na Região Amazônica em Anos de Eventos Extremos.}, booktitle = {Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental}, publisher = {Appris Editora}, year = {2018}, volume = {1}, number = {1}, pages = {107--117} } |
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Nascimento, J.P., Bela, M.M., Meller, B.B., Banducci, A.L., Rizzo, L.V., Vara-Vela, A.L., Barbosa, H.M.J., Gomes, H., Rafee, S.A.A., Franco, M.A., Carbone, S., Cirino, G.G., Souza, R.A.F., McKeen, S.A. and Artaxo, P. | Aerosols from anthropogenic and biogenic sources and their interactions – modeling aerosol formation, optical properties, and impacts over the central Amazon basin [BibTeX] |
2021 | Atmos. Chem. Phys. Vol. 21(9), pp. 6755-6779 |
article | DOI URL |
BibTeX:
@article{nascimento_aerosols_2021, author = {Nascimento, J. P. and Bela, M. M. and Meller, B. B. and Banducci, A. L. and Rizzo, L. V. and Vara-Vela, A. L. and Barbosa, H. M. J. and Gomes, H. and Rafee, S. A. A. and Franco, M. A. and Carbone, S. and Cirino, G. G. and Souza, R. A. F. and McKeen, S. A. and Artaxo, P.}, title = {Aerosols from anthropogenic and biogenic sources and their interactions – modeling aerosol formation, optical properties, and impacts over the central Amazon basin}, journal = {Atmos. Chem. Phys.}, year = {2021}, volume = {21}, number = {9}, pages = {6755--6779}, url = {https://acp.copernicus.org/articles/21/6755/2021/}, doi = {https://doi.org/10.5194/acp-21-6755-2021} } |
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Nascimento, J.P., Barbosa, H.M.J., Banducci, A.L., Rizzo, L.V., Vara-Vela, A.L., Meller, B.B., Gomes, H., Cezar, A., Franco, M.A., Ponczek, M., Wolff, S., Bela, M.M. and Artaxo, P. | Major Regional-Scale Production of O(3) and Secondary Organic Aerosol in Remote Amazon Regions from the Dynamics and Photochemistry of Urban and Forest Emissions | 2022 | Environ Sci Technol Vol. 56(14), pp. 9924-9935 |
article | DOI URL |
Abstract: The Amazon rainforest suffers increasing pressure from anthropogenic activities. A key aspect not fully understood is how anthropogenic atmospheric emissions within the basin interact with biogenic emissions and impact the forest's atmosphere and biosphere. We combine a high-resolution atmospheric chemical transport model with an improved emissions inventory and in-situ measurements to investigate a surprisingly high concentration of ozone (O(3)) and secondary organic aerosol (SOA) 150-200 km downwind of Manaus city in an otherwise pristine forested region. We show that atmospheric dynamics and photochemistry determine a gross production of secondary pollutants seen in the simulation. After sunrise, the erosion of the nocturnal boundary layer mixes natural forest emissions, rich in biogenic volatile organic compounds, with a lofted pollution layer transported overnight, rich in nitrogen oxides and formaldehyde. As a result, O(3) and SOA concentrations greater than approximately 47 ppbv and 1.8 mug m(-3), respectively, were found, with maximum concentrations occurring at 2 pm LT, 150-200 km downwind of Manaus city. These high concentrations affect a large primary forested area of about 11,250 km(2). These oxidative areas are under a NOx-limited regime so that changes in NOx emissions from Manaus have a significant impact on O(3) and SOA production. | |||||
BibTeX:
@article{nascimento_major_2022, author = {Nascimento, J. P. and Barbosa, H. M. J. and Banducci, A. L. and Rizzo, L. V. and Vara-Vela, A. L. and Meller, B. B. and Gomes, H. and Cezar, A. and Franco, M. A. and Ponczek, M. and Wolff, S. and Bela, M. M. and Artaxo, P.}, title = {Major Regional-Scale Production of O(3) and Secondary Organic Aerosol in Remote Amazon Regions from the Dynamics and Photochemistry of Urban and Forest Emissions}, journal = {Environ Sci Technol}, year = {2022}, volume = {56}, number = {14}, pages = {9924--9935}, note = {Edition: 2022/07/09}, url = {https://www.ncbi.nlm.nih.gov/pubmed/35801846}, doi = {https://doi.org/10.1021/acs.est.2c01358} } |
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Nascimento, H.E.M., Laurance, W.F., Condit, R., Laurance, S.G., D'Angelo, S. and Andrade, A.C. | Demographic and life-history correlates for Amazonian trees | 2005 | Journal of Vegetation Science Vol. 16(6), pp. 625-634 |
article | DOI URL |
Abstract: Questions: Which demographic and life-history differences are found among 95 sympatric tree species? Are there correlations among demographic parameters within this assemblage? Location: Central Amazonian rain forest. Methods: Using long-term data from 24 1-ha permanent plots, eight characteristics were estimated for each species: wood density, annual mortality rate, annual recruitment rate, mean stem diameter, maximum stem diameter, mean stem-growth rate, maximum stem-growth rate, population density. Results: An ordination analysis revealed that tree characteristics varied along two major axes of variation, the major gradient expressing light requirements and successional status, and the second gradient related to tree size. Along these gradients, four relatively discrete tree guilds could be distinguished: fast-growing pioneer species, shade-tolerant subcanopy species, canopy trees, and emergent species. Pioneers were uncommon and most trees were canopy or emergent species, which frequently had low mortality and recruitment. Wood density was negatively associated with tree mortality, recruitment, and growth rates when all species were considered. Growth rates varied markedly among and within species, with pioneers exhibiting far faster and less variable growth rates than did the other species. Slow growth in subcanopy species relative to canopy and emergent trees was not a simple consequence of mean tree size, but apparently resulted from physiological constraints imposed by low-light and other conditions in the forest understorey. Conclusions: Trees of Amazonian rain forests could be classified with some success into four relatively distinctive guilds. However, several demographic and life-history traits, such as those that distinguish early and late successional species, probably vary along a continuum, rather than being naturally grouped into relatively discrete categories. | |||||
BibTeX:
@article{nascimento_demographic_2005, author = {Nascimento, H. E. M. and Laurance, W. F. and Condit, R. and Laurance, S. G. and D'Angelo, S. and Andrade, A. C.}, title = {Demographic and life-history correlates for Amazonian trees}, journal = {Journal of Vegetation Science}, year = {2005}, volume = {16}, number = {6}, pages = {625--634}, url = {://WOS:000234454500003}, doi = {https://doi.org/10.1111/j.1654-1103.2005.tb02405.x} } |
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Nascimento, H.E.M. and Laurance, W.F. | Biomass dynamics in Amazonian forest fragments | 2004 | Ecological Applications Vol. 14(4), pp. S127-S138 |
article | URL |
Abstract: Habitat fragmentation affects aboveground biomass in Amazonian forests, with potentially important implications for carbon storage and greenhouse gas emissions. We assessed the dynamics of aboveground-biomass stocks by combining long-term (10-19 yr) data on mortality, damage, growth,. and, recruitment of large ( greater than or equal to10 cm diameter at breast height [dbh]) trees with measurements of nearly all other live and dead plant material (seedlings, saplings, small trees, palms, lianas, downed wood debris, snags, litter) in 50 1-ha plots in fragmented and continuous Amazonian forests. The key process altering biomass dynamics in fragmented forests is the chronically elevated mortality of large trees, which apparently results from microclimatic changes and increased wind turbulence near forest edges. This, in turn, accelerates the production of necromass and leads to significantly increased wood debris and litter on the forest floor. Near forest edges, frequent canopy disturbance increases the amount of light in the understory, resulting in accelerated tree recruitment, significantly higher biomass of small (510 cm dbh) trees, and higher liana densities. Surprisingly, the estimated annual turnover of wood debris increases significantly near forest edges, suggesting that decomposition is occurring more rapidly in fragmented than continuous forests. These results reveal that habitat fragmentation fundamentally alters the distribution and dynamics of aboveground biomass in Amazonian forests. The rate of carbon cycling probably increases sharply, both because long-lived canopy and emergent trees decline in favor of shorter-lived successional trees and lianas, and because necromass production and turnover,both appear to increase. Carbon storage in live vegetation also declines because small successional trees and lianas (which typically have low wood density) store substantially less carbon than do large, old-growth trees. Finally, the decline and rapid decay of live biomass in forest fragments may produce substantial atmospheric carbon emissions, above and beyond that resulting from deforestation per se. | |||||
BibTeX:
@article{nascimento_biomass_2004, author = {Nascimento, H. E. M. and Laurance, W. F.}, title = {Biomass dynamics in Amazonian forest fragments}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S127--S138}, url = {://WOS:000223269000012} } |
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Nascimento, H.E.M. and Laurance, W.F. | Total aboveground biomass in central Amazonian rainforests: a landscape-scale study | 2002 | Forest Ecology and Management Vol. 168(1-3), pp. 311-321 |
article | DOI URL |
Abstract: Amazonian forests play a key role in the global carbon cycle, but there is much uncertainty about the quantity and distribution of carbon stored in these forests. We quantified total aboveground dry biomass (TAGB) in undisturbed central Amazonian rainforests, based on detailed estimates of all live and dead plant material within 20 1 ha plots spanning an extensive (ca. 1000 km(2)) study area. TAGB values in our study area were very high, averaging 397.7 +/- 30.0 Mg ha(-1). The most important component of aboveground biomass was large (greater than or equal to10 cm diameter-at-breast-height (DBH)) trees, which comprised 81.9% of TAGB, followed by downed wood debris (7.0%), small trees, saplings, and seedlings (textless10 cm DBH; 5.3%), lianas (2.1%), litter (1.9%), snags (1.5%), and stemless palms (0.3%). Among large trees, aboveground biomass was greatest in intermediate-sized (20-50 cm DBH) stems (46.7% of TAGB), with very large (greater than or equal to60 cm DBH) trees also containing substantial biomass (13.4% of TAGB). There were no significant correlations between large tree biomass and that of any other live or dead biomass component. An analysis based on the variability of our samples suggested that just 3-4 randomly positioned I ha plots would be sufficient to provide a reasonable estimate of mean TAGB in a landscape such as ours (with 95% confidence intervals being textless10% of the mean). This suggests that efforts to quantify Amazon forest biomass should be extensive rather than intensive; researchers should sample many geographically separate areas with a few plots each, rather than sampling a small number of areas more intensively. Published by Elsevier Science B.V. | |||||
BibTeX:
@article{nascimento_total_2002, author = {Nascimento, H. E. M. and Laurance, W. F.}, title = {Total aboveground biomass in central Amazonian rainforests: a landscape-scale study}, journal = {Forest Ecology and Management}, year = {2002}, volume = {168}, number = {1-3}, pages = {311--321}, url = {://WOS:000177478900025}, doi = {https://doi.org/10.1016/s0378-1127(01)00749-6} } |
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Nascimento, H.E.M., Andrade, A.C.S., Camargo, J.L.C., Laurnce, W.F., Laurance, S.G. and Ribeiro, J.E.L. | Effects of the surrounding matrix on tree recruitment in Amazonian forest fragments | 2006 | Conservation Biology Vol. 20(3), pp. 853-860 |
article | DOI URL |
Abstract: Little is known about how the surrounding modified matrix affects tree recruitment infragmented forests. We contrasted effects of two different matrix types, Vismia- and Cecropia-dominated regrowth, on recruitment of pioneer tree species in forest fragments in central Amazonia. Our analyses were based on 22, 1-ha plots in seven experimental forest fragments ranging in size from I to 100 ha. By 13 to 17 years after fragmentation, the population density of pioneer trees was significantly higher in plots surrounded by Vismia regrowth than in plots surrounded by Cecropia regrowth, and the species composition and dominance of pioneers differed markedly between the two matrix types. Cecropia sciadophylla was the most abundant pioneer in fragments surrounded by Cecropia regrowth (constituting nearly 50% of all pioneer trees), whereas densities of species in Vismia-surrounded fragments were distributed more evenly. Thus the surrounding matrix had a strong influence on patterns of tree recruitment in Amazonian forest fragments. | |||||
BibTeX:
@article{nascimento_effects_2006, author = {Nascimento, H. E. M. and Andrade, A. C. S. and Camargo, J. L. C. and Laurnce, W. F. and Laurance, S. G. and Ribeiro, J. E. L.}, title = {Effects of the surrounding matrix on tree recruitment in Amazonian forest fragments}, journal = {Conservation Biology}, year = {2006}, volume = {20}, number = {3}, pages = {853--860}, note = {Edition: 2006/08/17}, url = {://WOS:000238313200044}, doi = {https://doi.org/10.1111/j.1523-1739.2006.00344.x} } |
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Nardoto, G., Quesada, C., Patiño, S., Saiz, G., Baker, T., Schwarz, M., Schrodt, F., Feldpausch, T.R., Domingues, T., Marimon, B., Marimon Junior, B.-H., Vieira, I., Silveira, M., Bird, M., Phillips, O.L., Lloyd, J. and Martinelli, L. | Basin-wide variations in Amazon forest nitrogen-cycling characteristics as inferred from plant and soil 15N:14N measurements [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2,), pp. 173-187 |
article | |
BibTeX:
@article{nardoto_basin-wide_2014, author = {Nardoto, G.B. and Quesada, C.A. and Patiño, S. and Saiz, G. and Baker, T.R. and Schwarz, M. and Schrodt, F. and Feldpausch, T. R. and Domingues, T.F. and Marimon, B.S. and Marimon Junior, Ben-Hur and Vieira, I.C.G. and Silveira, M. and Bird, M.I. and Phillips, O. L. and Lloyd, J. and Martinelli, L.A.}, title = {Basin-wide variations in Amazon forest nitrogen-cycling characteristics as inferred from plant and soil 15N:14N measurements}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2,}, pages = {173--187} } |
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Nardoto, G.B., Henry Balbaud Ometto, J.P., Ehleringer, J.R., Higuchi, N., da Cunha Bustamante, M.M. and Martinelli, L.A. | Understanding the Influences of Spatial Patterns on N Availability Within the Brazilian Amazon Forest | 2008 | Ecosystems Vol. 11(8), pp. 1234-1246 |
article | DOI URL |
Abstract: Nitrogen variations at different spatial scales and integrated across functional groups were addressed for lowland tropical forests in the Brazilian Amazon as follows: (1) how does N availability vary across the region over different spatial scales (regional x landscape scale); ( 2) how are these variations in N availability integrated across plant functional groups ( legume 9 non-legume trees). Leaf N, P, and Ca concentrations as well the leaf N isotope ratios (delta(15)N) from a large set of legume and non-legume tree species were measured. Legumes had higher foliar N/Ca ratios than non-legumes, consistent with the high energetic costs in plant growth associated with higher foliar P/Ca ratios found in legumes than in non-legumes. At the regional level, foliar delta(15)N decreased with increasing rainfall. At the landscape level, N availability was higher in the forests on clayey soils on the plateau than in forests on sandier soils. The isotope as well as the non-isotope data relationships here documented, explain to a large extent the variation in delta(15)N signatures across gradients of rainfall and soil. Although at the regional level, the precipitation regime is a major determinant of differences in N availability, at the landscape level, under the same precipitation regime, soil type seems to be a major factor influencing the availability of N in the Brazilian Amazon forest. | |||||
BibTeX:
@article{nardoto_understanding_2008, author = {Nardoto, Gabriela Bielefeld and Henry Balbaud Ometto, Jean Pierre and Ehleringer, James R. and Higuchi, Niro and da Cunha Bustamante, Mercedes Maria and Martinelli, Luiz Antonio}, title = {Understanding the Influences of Spatial Patterns on N Availability Within the Brazilian Amazon Forest}, journal = {Ecosystems}, year = {2008}, volume = {11}, number = {8}, pages = {1234--1246}, url = {://WOS:000260951100002}, doi = {https://doi.org/10.1007/s10021-008-9189-1} } |
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Nardoto, G.B., Bustamante, M.M.D., Pinto, A.S. and Klink, C.A. | Nutrient use efficiency at ecosystem and species level in savanna areas of Central Brazil and impacts of fire | 2006 | Journal of Tropical Ecology Vol. 22, pp. 191-201 |
article | DOI URL |
Abstract: Nutrient resorption efficiency of woody plants, litterfall and nutrient fluxes were investigated in a burned and an unburned cerrado plot between October 199 7 and September 1999. A large experiment (Fire project, Brasilia, Brazil) on the effects of prescribed burnings was initiated in 1992. Cerrado plots were delimited and subjected to different fire regimes. Seasonal trend of litterfall was similar in both plots but the production in the burned plot was 42.2 g m(-2) y(-1) before the fourth prescribed fire (September 1998) and decreased by 22%, 1 y after burning while in the unburned plot it was around 2 30 g m(-2) y(-1). Although nutrient concentrations in leaf litter were higher in the burned plot, the nutrient fluxes were 60-80% lower than in the unburned plot. Nutrient use efficiency (ecosystem level) was 4373 for P and 137 for N. Measured resorption efficiency for 10 cerrado species ranged front 14.5 to 37.2% for N and from 40 to 70.4%, for P and in general. there were no differences between plots. N is in short supply, partly because of fire history, but the results, both at ecosystem and species levels (mean N/P in fresh leaves was 18), indicated it stronger limitation by P than by N. | |||||
BibTeX:
@article{nardoto_nutrient_2006, author = {Nardoto, G. B. and Bustamante, M. M. D. and Pinto, A. S. and Klink, C. A.}, title = {Nutrient use efficiency at ecosystem and species level in savanna areas of Central Brazil and impacts of fire}, journal = {Journal of Tropical Ecology}, year = {2006}, volume = {22}, pages = {191--201}, url = {://WOS:000235417600008}, doi = {https://doi.org/10.1017/s0266467405002865} } |
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Nardoto, G.B. and Bustamante, M.M.D. | Effects of fire on soil nitrogen dynamics and microbial biomass in savannas of Central Brazil | 2003 | Pesquisa Agropecuaria Brasileira Vol. 38(8), pp. 955-962 |
article | URL |
Abstract: The objective of this work was to study the effects of fire on net N mineralization and soil microbial biomass in burned and unburned cerrado stricto sensu sites. The study was carried out from April 1998 to April 2000. The pH values were significantly higher in the burned site while soil moisture content was significantly higher in the unburned site (Ptextless0.05). The soil C/N ratio was 22/1 and the available NO3-N ranged between 1.5 and 2.8 mg kg(-1) dry weight. However, the NH4-N concentration ranged between 3 and 34 mg kg(-1) dry weight in the burned site and between 3 and 22 mg kg(-1) dry weight in the unburned site. The NH4-N increased after fire, but no significant changes were observed for NO3-N (Ptextless0.05). The NO3-N accumulation occurred in short periods during the rainy season. The rates of net N mineralization increased during the rainy season while reductions in soil microbial biomass were observed at both sites. This suggested that the peak in microbial activities occurred with the first rain events, with an initial net immobilization followed by net mineralization. Both sites presented the same pattern for mineralization/immobilization, however, the amount of inorganic-N cycled annually in unburned site was 14.7 kg ha(-1) per year while the burned site presented only 3.8 kg ha(-1) of inorganic-N, one year after the burning. | |||||
BibTeX:
@article{nardoto_effects_2003, author = {Nardoto, G. B. and Bustamante, M. M. D.}, title = {Effects of fire on soil nitrogen dynamics and microbial biomass in savannas of Central Brazil}, journal = {Pesquisa Agropecuaria Brasileira}, year = {2003}, volume = {38}, number = {8}, pages = {955--962}, url = {://WOS:000185628200008} } |
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Nair, K.N., Freitas, E.D., Sanchez-Ccoyllo, O.R., Dias, M., Dias, P.L.S., Andrade, M.F. and Massambani, O. | Dynamics of urban boundary layer over Sao Paulo associated with mesoscale processes | 2004 | Meteorology and Atmospheric Physics Vol. 86(1-2), pp. 87-98 |
article | DOI URL |
Abstract: Examination of the Doppler SODAR data from Sao Paulo, Brazil, has given valuable information on the coupling between planetary boundary layer (PBL) and the free atmosphere above, which is reported here. In this communication a case study, on the dynamics of the urban boundary layer over the Metropolitan Area of Sao Paulo (MASP), Brazil, is examined for July 27, 1999 when a multiple gravity wave (GW), a low-level jet (LLJ) and a cold front (CF) all occurred in one single day in succession, making use of data from Doppler SODAR, surface meteorological instruments, satellite imageries and model derived values. The experimental findings are compared to provide validations of ground truth with the model-derived profiles based on the mesoscale analysis of Regional Atmospheric Modelling System (RAMS). It is seen that the multiple GW, the LLJ and the CF have different types of nonlinear coupling between the PBL and the free atmosphere. However, there is convincing matching between Doppler SODAR derived features, those of mesoscale analysis from RAMS and satellite view of cloud dynamics. The study provided valuable information on (i) the very nature of these events, (ii) the nonlinear hydrodynamical coupling between the PBL and the free atmosphere above, during such events, and (iii) the possible mechanism of CF influencing the formation of GW and LLJ. | |||||
BibTeX:
@article{nair_dynamics_2004, author = {Nair, K. N. and Freitas, E. D. and Sanchez-Ccoyllo, O. R. and Dias, Mafs and Dias, P. L. S. and Andrade, M. F. and Massambani, O.}, title = {Dynamics of urban boundary layer over Sao Paulo associated with mesoscale processes}, journal = {Meteorology and Atmospheric Physics}, year = {2004}, volume = {86}, number = {1-2}, pages = {87--98}, url = {://WOS:000221116100007}, doi = {https://doi.org/10.1007/s00703-003-0617-7} } |
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Nagy, L., Forsberg, B. and Artaxo, P. | Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin [BibTeX] |
2016 | book | DOI | |
BibTeX:
@book{227_interactions_2016, author = {Nagy, Laszlo and Forsberg, Bruce and Artaxo, Paulo}, title = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Myneni, R., Yang, W.Z., Nemani, R., Huete, A., Dickinson, R., Knyazikhin, Y., Didan, K., Fu, R., Juarez, R.I.N., Saatchi, S.S., Hashimoto, H., Ichii, K., Shabanov, N., Tan, B., Ratana, P., Privette, J., Morisette, J., Vermote, E., Roy, D., Wolfe, R., Friedl, M., Running, S., Votava, P., El-Saleous, N., Devadiga, S., Su, Y. and Salomonson, V. | Large seasonal swings in leaf area of Amazon rainforests | 2007 | Proceedings of the National Academy of Sciences of the United States of America Vol. 104(12), pp. 4820-4823 |
article | DOI URL |
Abstract: Despite early speculation to the contrary, all tropical forests studied to date display seasonal variations in the presence of new leaves, flowers, and fruits. Past studies were focused on the timing of phenological events and their cues but not on the accompanying changes in leaf area that regulate vegetation-atmosphere exchanges of energy, momentum, and mass. Here we report, from analysis of 5 years of recent satellite data, seasonal swings in green leaf area of approximate to 25% in a majority of the Amazon rainforests. This seasonal cycle is timed to the seasonality of solar radiation in a manner that is suggestive of anticipatory and opportunistic patterns of net leaf flushing during the early to mid part of the light-rich dry season and net leaf abscission during the cloudy wet season. These seasonal swings in leaf area may be critical to initiation of the transition from dry to wet season, seasonal carbon balance between photosynthetic gains and respiratory losses, and litterfall nutrient cycling in moist tropical forests. | |||||
BibTeX:
@article{myneni_large_2007, author = {Myneni, R.B. and Yang, W. Z. and Nemani, R.R. and Huete, A.R. and Dickinson, R.E. and Knyazikhin, Y. and Didan, K. and Fu, R. and Juarez, R. I. N. and Saatchi, S. S. and Hashimoto, H. and Ichii, K. and Shabanov, N.V. and Tan, B. and Ratana, P. and Privette, J.L. and Morisette, J.T. and Vermote, E.F. and Roy, D.P. and Wolfe, R.E. and Friedl, M.A. and Running, S.W. and Votava, P. and El-Saleous, N. and Devadiga, S. and Su, Y. and Salomonson, V.V.}, title = {Large seasonal swings in leaf area of Amazon rainforests}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2007}, volume = {104}, number = {12}, pages = {4820--4823}, note = {Edition: 2007/03/16}, url = {://WOS:000245256700012}, doi = {https://doi.org/10.1073/pnas.0611338104} } |
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Muza, M. and Carvalho, L. | Variabilidade Intrasazonal e Interanual de Extremos na Precipitação sobre o Centro-Sul da Amazônia durante o verão Austral [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3a), pp. 29-41 |
article | |
BibTeX:
@article{muza_variabilidade_2006, author = {Muza, M.N. and Carvalho, L.M.V.}, title = {Variabilidade Intrasazonal e Interanual de Extremos na Precipitação sobre o Centro-Sul da Amazônia durante o verão Austral}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3a}, pages = {29--41} } |
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Murugesan, K., Balasubramani, P., Murugan, P.R. and Sankaranarayanan, S. | Color-based SAR image segmentation using HSV+FKM clustering for estimating the deforestation rate of LBA-ECO LC-14 modeled deforestation scenarios, Amazon basin: 2002–2050 | 2021 | Arabian Journal of Geosciences Vol. 14(9), pp. 777 |
article | DOI URL |
Abstract: Image segmentation is an essential process for image evaluation tactics. Synthetic aperture radar (SAR) image segmentation can be implemented for a vast magnificence of various problems. Due to the existence of speckle noise in SAR images, the edge attributes of the images are unknown. This leads over or under segmentation and produces poor quality of segmented results. In this paper, the deforestation rate of Amazon, South America, has been determined by using the color space-based SAR image segmentation. Since the fuzzy K-means (FKM) clustering technique is robust to speckle noise, it is combined with different color spaces for better segmentation. The proposed method has been compared with different existing methods, and it gives better segmentation results with a segmentation accuracy of 99.5%, Jaccard index of 99%, recall of 99.5%, and specificity of 99.7% with the minimum error rate of 0.004. The segmentation accuracy of 14.9% and the Jaccard index of 10.3% have been improved when compared with FKM clustering technique. This paper suggests that HSV+FKM is a suitable technique for the segmentation of LBA-ECO LC-14 modeled deforestation scenarios. Brazil’s National Institute of Spatial Research (INPE) discovered that the span of Amazon could be diminished to 50% by 2050. This paper also predicts that the Amazon rainforest will be reduced to 43.26% at the end of 2050. | |||||
BibTeX:
@article{murugesan_color-based_2021, author = {Murugesan, Kalaiyarasi and Balasubramani, Perumal and Murugan, Pallikonda Rajasekaran and Sankaranarayanan, Saravanan}, title = {Color-based SAR image segmentation using HSV+FKM clustering for estimating the deforestation rate of LBA-ECO LC-14 modeled deforestation scenarios, Amazon basin: 2002–2050}, journal = {Arabian Journal of Geosciences}, year = {2021}, volume = {14}, number = {9}, pages = {777}, url = {https://doi.org/10.1007/s12517-021-07069-4}, doi = {https://doi.org/10.1007/s12517-021-07069-4} } |
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Muniz, F.J. and L.S., N.P. | NOÇÕES DE HIDROGEOGRAFIA - CONHECENDO O MEU RIO MADEIRA [BibTeX] |
2014 | , pp. 36p.School: INPA | techreport | |
BibTeX:
@techreport{muniz_nocoes_2014, author = {Muniz, Filizola Júnior, N.P., L.S.}, title = {NOÇÕES DE HIDROGEOGRAFIA - CONHECENDO O MEU RIO MADEIRA}, school = {INPA}, year = {2014}, pages = {36p.}, note = {Edition: PRONEX/FAPEAM} } |
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Moutinho, P., Nepstad, D.C. and Davidson, E.A. | Influence of leaf-cutting ant nests on secondary forest growth and soil properties in Amazonia | 2003 | Ecology Vol. 84(5), pp. 1265-1276 |
article | DOI URL |
Abstract: Leaf-cutting ants (Atta spp.) often increase in abundance following deforestation and may have an important effect on forest succession on abandoned land. In this study, we evaluated the effects of leaf-cutting ant (Atta sexdens) activity on physical and chemical properties of soil, root distribution, and tree growth in a 17-yr-old secondary forest in eastern Amazonia, Brazil. We compared the soil properties and root distribution in shafts excavated into five mature nests and at 15 m distanced from each nest mound. We evaluated the nest effects on vegetation measuring the stem diameter growth of nine tree species and predawn leaf water potential of the tree species, Banara guianensis, along a gradient of increasing distance from the nest mounds. The growth of seedlings (Cecropia sp.) in pots containing different proportions of mineral soil and organic matter removed from nest refuse chambers was also compared. The deep soil beneath A. sexdens nests at different depths (100, 200, and 300 cm) presented a low (fivefold, P textless 0.01) resistance to penetration and was rich in Ca (three- to fourfold, P = 0.06-0.02), K (7-14-fold, P textless 0.05), and Mg (two- to threefold, P = 0.09 for 200 cm depth) when compared to non-nest soil. These changes in nest soil properties were accompanied by increases in coarse root biomass (textgreater2 mm diameter, three- to fourfold) and fine root biomass (textless2 mm, 10-50 fold). However, stem diameter growth was generally not affected by distance from the nest. The growth of Cecropia sp. seedlings in a pot experiment was favored by the addition of organic matter from the refuse chambers. Banara guianensis trees experienced greater water stress (low predawn water potential) close to the nest mound, perhaps indicating increased competition for soil water that may have accompanied the proliferation of roots of several species in the nest. The competing Atta effects of defoliation vs. deep soil tillage and nutrient enrichment upon secondary forest growth are difficult to compare. Atta's modification of soil physical and chemical properties point to its potential role in facilitating the rapid recovery of deep root systems and soil water uptake previously observed in this secondary forest. | |||||
BibTeX:
@article{moutinho_influence_2003, author = {Moutinho, P. and Nepstad, D. C. and Davidson, E. A.}, title = {Influence of leaf-cutting ant nests on secondary forest growth and soil properties in Amazonia}, journal = {Ecology}, year = {2003}, volume = {84}, number = {5}, pages = {1265--1276}, url = {://WOS:000184120500019}, doi = {https://doi.org/10.1890/0012-9658(2003)084%5B1265:iolano%5D2.0.co;2} } |
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Moura, Y.d., Galvão, L.S., Hilker, T., Wu, J., Saleska, S., Amaral, C.H.d., Nelson, B.W., Lopes, A.P., Wiedeman, K.K., Neill Prohaska, Raimundo Cosme de Oliveira, Carolyne Bueno Machado and Luiz E.O.C. Aragão | Spectral analysis of amazon canopy phenology during the dry season using a tower hyperspectral camera and modis observations [BibTeX] |
2017 | ISPRS Journal of Photogrammetry and Remote Sensing Vol. 131, pp. 52-64 |
article | |
BibTeX:
@article{moura_spectral_2017, author = {Moura, Y.M. de and Galvão, L. S. and Hilker, T. and Wu, J. and Saleska, S. and Amaral, C. H. do and Nelson, B. W. and Lopes, A. P. and Wiedeman, Kenia K. and Neill Prohaska and Raimundo Cosme de Oliveira and Carolyne Bueno Machado and Luiz E.O.C. Aragão}, title = {Spectral analysis of amazon canopy phenology during the dry season using a tower hyperspectral camera and modis observations}, journal = {ISPRS Journal of Photogrammetry and Remote Sensing}, year = {2017}, volume = {131}, pages = {52--64} } |
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Moura, Y.M., Hilker, T., Lyapustin, A.I., Soares, G.L., Santos, J.R., Anderson, L.O., Sousa, C.H.R. and Arai, E. | Seasonality and drought effects of Amazonian forests observed from multi-angle satellite data [BibTeX] |
2015 | Remote Sensing of Environment Vol. 171, pp. 278-290 |
article | DOI |
BibTeX:
@article{moura_seasonality_2015, author = {Moura, Y. M. and Hilker, T. and Lyapustin, A. I. and Soares, G. L. and Santos, J. R. and Anderson, Liana O. and Sousa, C. H. R. and Arai, E.}, title = {Seasonality and drought effects of Amazonian forests observed from multi-angle satellite data}, journal = {Remote Sensing of Environment}, year = {2015}, volume = {171}, pages = {278--290}, doi = {https://doi.org/10.1016/j.rse.2015.10.015} } |
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Moura, V., von Randow, C. and Manzi, A.O. | Estimativa do footprint de torres em área de platô e baixio na Reserva Cuieiras, Amazônia Central [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 387-390 |
article | |
BibTeX:
@article{moura_estimativa_2007, author = {Moura, Veber and von Randow, Celso and Manzi, Antonio Ocimar}, title = {Estimativa do footprint de torres em área de platô e baixio na Reserva Cuieiras, Amazônia Central}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {387--390} } |
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Moura, Q.d., Ruivo, M.d.L.P., Rodrigues, H., Rocha, E., Silva Junior, J.d.A., Vasconcelos, S., Andrade, M. and Manes, C.-L.d.O. | Variação sazonal da população de bactérias e fungos e dos teores de nitrato e amônio do solo nos sítios do LBA e PPBIO, na amazônia oriental [BibTeX] |
2015 | Revista Brasileira de Meteorologia Vol. 30(3), pp. 265 - 274 |
article | DOI |
BibTeX:
@article{moura_variacao_2015, author = {Moura, Q.L. de and Ruivo, M. de L. P. and Rodrigues, H.J.B. and Rocha, E.J.P. and Silva Junior, J. de A. and Vasconcelos, S.S. and Andrade, M.C. and Manes, C.-L. de O.}, title = {Variação sazonal da população de bactérias e fungos e dos teores de nitrato e amônio do solo nos sítios do LBA e PPBIO, na amazônia oriental}, journal = {Revista Brasileira de Meteorologia}, year = {2015}, volume = {30}, number = {3}, pages = {265 -- 274}, doi = {https://doi.org/10.1590/0102-778620140104} } |
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Moura, C., Santos A.B., M. and Querino | Atmosfera e Sociedade: aspectos multi e interdisciplinares da meteorologia [BibTeX] |
2011 | Vol. II |
book | |
BibTeX:
@book{ed_atmosfera_2011, author = {Moura, C.A.S.; Santos, A.B., M.A.L.; Querino}, title = {Atmosfera e Sociedade: aspectos multi e interdisciplinares da meteorologia}, publisher = {EDUFAL}, year = {2011}, volume = {II} } |
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Moura, M., Meixner, F., Trebs, I., Molion, L. and Nascimento Filho, M. | Medições de NO - NO2 - O3 na amazônia central durante o Experimento LBA/CLAIRE-2001 [BibTeX] |
2004 | Revista Brasileira de Meteorologia Vol. 19(1), pp. 49-58 |
article | |
BibTeX:
@article{moura_medicoes_2004, author = {Moura, M.A.L. and Meixner, F.X. and Trebs, I. and Molion, L.C.B. and Nascimento Filho, M.F.}, title = {Medições de NO - NO2 - O3 na amazônia central durante o Experimento LBA/CLAIRE-2001}, journal = {Revista Brasileira de Meteorologia}, year = {2004}, volume = {19}, number = {1}, pages = {49--58} } |
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Moura Meixner F.X., T.I.L.R.A.M.N.F.M.M. | Evidencia observacional das brisas do lago de Balbina (Amazonas) e seus efeitos sobre a concentração do ozônio [BibTeX] |
2004 | Acta Amazonica Vol. 34(4), pp. 605-611 |
article | |
BibTeX:
@article{moura_evidencia_2004, author = {Moura, Meixner F.X., Trebs I., Lyra R.F.F., Andreae M.O., Nascimento Filho M.F., M.A.L.}, title = {Evidencia observacional das brisas do lago de Balbina (Amazonas) e seus efeitos sobre a concentração do ozônio}, journal = {Acta Amazonica}, year = {2004}, volume = {34}, number = {4}, pages = {605--611} } |
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Mõttus, M., Aragão, L., Bäck, J., Hernández-Clemente, R., Maeda, E.E., Markiet, V., Nichol, C., Oliveira, R.C.d. and Restrepo-Coupe, N. | Diurnal Changes in Leaf Photochemical Reflectance Index in Two Evergreen Forest Canopies [BibTeX] |
2019 | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Vol. 12(7), pp. 2236-2243 |
article | DOI |
BibTeX:
@article{mottus_diurnal_2019, author = {Mõttus, M. and Aragão, L. and Bäck, J. and Hernández-Clemente, R. and Maeda, E. E. and Markiet, V. and Nichol, C. and Oliveira, R. C. de and Restrepo-Coupe, N.}, title = {Diurnal Changes in Leaf Photochemical Reflectance Index in Two Evergreen Forest Canopies}, journal = {IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing}, year = {2019}, volume = {12}, number = {7}, pages = {2236--2243}, doi = {https://doi.org/10.1109/JSTARS.2019.2891789} } |
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Mota, M.A.S.d., Silva, L.M.d. and Sá, L.D.A. | Variabilidade da altura da camada de mistura (CM) e da energia potencial convectiva disponível (CAPE) durante o Wet-AMC/LBA [BibTeX] |
2007 | Revista Ciencia e Natura Vol. Edição Especial, pp. 419-422 |
article | |
BibTeX:
@article{mota_variabilidade_2007, author = {Mota, Maria Aurora Santos da and Silva, Ludmila Monteiro da and Sá, Leonardo Deane Abreu}, title = {Variabilidade da altura da camada de mistura (CM) e da energia potencial convectiva disponível (CAPE) durante o Wet-AMC/LBA}, journal = {Revista Ciencia e Natura}, year = {2007}, volume = {Edição Especial}, pages = {419--422} } |
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Mota, M. and Nobre, C. | Relação da variabilidade da Energia Potencial Convectiva Disponível (CAPE) com a Precipitação e a Alta da Bolívia durante a campanha “Wet-AMC/LBA” [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 344-355 |
article | |
BibTeX:
@article{mota_relacao_2006, author = {Mota, M.A.S. and Nobre, C.A.}, title = {Relação da variabilidade da Energia Potencial Convectiva Disponível (CAPE) com a Precipitação e a Alta da Bolívia durante a campanha “Wet-AMC/LBA”}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {344--355} } |
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Mota, M. and Mendonça, A. | Comparação dos Esquemas de Convecção Kuo e RAS Usando o Modelo Atmosférico Global do CPTEC Durante o Experimento WetAMC/LBA [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 356-370 |
article | |
BibTeX:
@article{mota_comparacao_2006, author = {Mota, M.A.S. and Mendonça, A.M.}, title = {Comparação dos Esquemas de Convecção Kuo e RAS Usando o Modelo Atmosférico Global do CPTEC Durante o Experimento WetAMC/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {356--370} } |
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Mota de Oliveira, S., Duijm, E., Stech, M., Ruijgrok, J., Polling, M., Barbosa, C.G.G., Cerqueira, G.R., Nascimento, A.H.M., Godoi, R.H.M., Taylor, P.E., Wolff, S., Weber, B. and Kesselmeier, J. | Life is in the air: An expedition into the Amazonian atmosphere | 2022 | Frontiers in Ecology and Evolution Vol. 10 |
article | DOI URL |
Abstract: Biological particles suspended in the atmosphere have a crucial role in the dynamics of the biosphere underneath. Although much attention is paid for the chemical and physical properties of these particles, their biological taxonomic identity, which is relevant for ecological research, remains little studied. We took air samples at 300 meters above the forest in central Amazonia, in seven periods of 7 days, and used high-throughput DNA sequencing techniques to taxonomically identify airborne fungal and plant material. The use of a molecular identification technique improved taxonomic resolution when compared to morphological identification. This first appraisal of airborne diversity showed that fungal composition was strikingly different from what has been recorded in anthropogenic regions. For instance, basidiospores reached 30% of the OTUs instead of 3–5% as found in the literature; and the orders Capnodiales and Eurotiales—to which many allergenic fungi and crop pathogens belong—were much less frequently recorded than Pleosporales, Polyporales, and Agaricales. Plant OTUs corresponded mainly to Amazonian taxa frequently present in pollen records such as the genera Helicostilys and Cecropia and/or very abundant in the region such as Pourouma and Pouteria. The origin of extra-Amazonian plant material is unknown, but they belong to genera of predominantly wind-pollinated angiosperm families such as Poaceae and Betulaceae. Finally, the detection of two bryophyte genera feeds the debate about the role of long distance dispersal in the distribution of these plants. | |||||
BibTeX:
@article{mota_de_oliveira_life_2022, author = {Mota de Oliveira, Sylvia and Duijm, Elza and Stech, Michael and Ruijgrok, Jasmijn and Polling, Marcel and Barbosa, Cybelli G. G. and Cerqueira, Gabriela R. and Nascimento, Antônio H. M. and Godoi, Ricardo H. M. and Taylor, Philip E. and Wolff, Stefan and Weber, Bettina and Kesselmeier, Jürgen}, title = {Life is in the air: An expedition into the Amazonian atmosphere}, journal = {Frontiers in Ecology and Evolution}, year = {2022}, volume = {10}, url = {https://www.frontiersin.org/articles/10.3389/fevo.2022.789791}, doi = {https://doi.org/10.3389/fevo.2022.789791} } |
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Morton, D., Shimabukuro, Y., Rudorff, B., Lima, A., Freitas, R. and DeFries, R. | Challenges for conservation at the agricultural frontier: deforestation, fire, and land use dynamics in Mato Grosso [BibTeX] |
2007 | Revista Ambiente e Agua Vol. 2(1), pp. doi:10.4136/1980-993X |
article | |
BibTeX:
@article{morton_challenges_2007, author = {Morton, D.C. and Shimabukuro, Y.E. and Rudorff, B.F.T. and Lima, A. and Freitas, R.M. and DeFries, R.S.}, title = {Challenges for conservation at the agricultural frontier: deforestation, fire, and land use dynamics in Mato Grosso}, journal = {Revista Ambiente e Agua}, year = {2007}, volume = {2}, number = {1}, pages = {doi:10.4136/1980--993X} } |
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Morton, D.C., Sales, M.H., Souza Jr, C.M. and Griscom, B. | Historic emissions from deforestation and forest degradation in Mato Grosso, Brazil: 1) source data uncertainties [BibTeX] |
2011 | Carbon Balance and Management Vol. 6(18), pp. http://www.cbmjournal.com/content/6/1/18 |
article | |
BibTeX:
@article{morton_historic_2011, author = {Morton, Douglas C and Sales, Marcio H and Souza Jr, Carlos M and Griscom, Bronson}, title = {Historic emissions from deforestation and forest degradation in Mato Grosso, Brazil: 1) source data uncertainties}, journal = {Carbon Balance and Management}, year = {2011}, volume = {6}, number = {18}, pages = {http://www.cbmjournal.com/content/6/1/18} } |
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Morton, D.C., Rubio, J., Cook, B.D., Gastellu-Etchegorry, J.-P., Longo, M., Choi, H., Hunter, M. and Keller, M. | Amazon forest structure generates diurnal and seasonal variability in light utilization [BibTeX] |
2016 | Biogeosciences Vol. 13, pp. 2195-2206 |
article | DOI |
BibTeX:
@article{morton_amazon_2016, author = {Morton, Douglas C. and Rubio, Jérémy and Cook, Bruce D. and Gastellu-Etchegorry, Jean-Philippe and Longo, Marcos and Choi, Hyeungu and Hunter, Maria and Keller, Michael}, title = {Amazon forest structure generates diurnal and seasonal variability in light utilization}, journal = {Biogeosciences}, year = {2016}, volume = {13}, pages = {2195--2206}, doi = {https://doi.org/10.5194/bg-13-2195-2016} } |
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Morton, D.C., Nagol, J., Carabajal, C.C., Rosette, J., Palace, M., Cook, B.D., Vermote, E., Harding, D. and North, P. | Amazon forests maintain consistent canopy structure and greenness during the dry season [BibTeX] |
2014 | Nature Vol. 506, pp. 221-224 |
article | DOI |
BibTeX:
@article{morton_amazon_2014, author = {Morton, D. C. and Nagol, J. and Carabajal, C. C. and Rosette, J. and Palace, M. and Cook, B. D. and Vermote, E.F. and Harding, D.J. and North, P.R.J.}, title = {Amazon forests maintain consistent canopy structure and greenness during the dry season}, journal = {Nature}, year = {2014}, volume = {506}, pages = {221--224}, doi = {https://doi.org/10.1038/nature13006} } |
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Morton, D.C., DeFries, R.S., Shimabukuro, Y.E., Anderson, L.O., Espirito-Santo, F.D.B., Hansen, M. and Carroll, M. | Rapid assessment of annual deforestaion in the Brazilian Amazon using MODIS data | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: The Brazilian government annually assesses the extent of deforestation in the Legal Amazon for a variety of scientific and policy applications. Currently, the assessment requires the processing and storing of large volumes of Landsat satellite data. The potential for efficient, accurate, and less data-intensive assessment of annual deforestation using data from NASA's Moderate Resolution Imaging Spectroradiometer ( MODIS) at 250-m resolution is evaluated. Landsat-derived deforestation estimates are compared to MODIS-derived estimates for six Landsat scenes with five change-detection algorithms and a variety of input data - Surface Reflectance (MOD09), Vegetation Indices (MOD13), fraction images derived from a linear mixing model, Vegetation Cover Conversion (MOD44A), and percent tree cover from the Vegetation Continuous Fields (MOD44B) product. Several algorithms generated consistently low commission errors ( positive predictive value near 90%) and identified more than 80% of deforestation polygons larger than 3 ha. All methods accurately identified polygons larger than 20 ha. However, no method consistently detected a high percent of Landsat-derived deforestation area across all six scenes. Field validation in central Mato Grosso confirmed that all MODIS-derived deforestation clusters larger than three 250-m pixels were true deforestation. Application of this field-validated method to the state of Mato Grosso for 2001 - 04 highlighted a change in deforestation dynamics; the number of large clusters (textgreater 10 MODIS pixels) that were detected doubled, from 750 between August 2001 and August 2002 to over 1500 between August 2003 and August 2004. These analyses demonstrate that MODIS data are appropriate for rapid identification of the location of deforestation areas and trends in deforestation dynamics with greatly reduced storage and processing requirements compared to Landsat-derived assessments. However, the MODIS-based analyses evaluated in this study are not a replacement for high-resolution analyses that estimate the total area of deforestation and identify small clearings. | |||||
BibTeX:
@article{morton_rapid_2005, author = {Morton, D. C. and DeFries, R. S. and Shimabukuro, Y. E. and Anderson, L. O. and Espirito-Santo, F. D. B. and Hansen, M. and Carroll, M.}, title = {Rapid assessment of annual deforestaion in the Brazilian Amazon using MODIS data}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://000241213000001} } |
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Morton, D.C., DeFries, R.S., Shimabukuro, Y.E., Anderson, L.O., Arai, E., del Bon Espirito-Santo, F., Freitas, R. and Morisette, J. | Cropland expansion changes deforestation dynamics in the southern Brazilian Amazon | 2006 | Proceedings of the National Academy of Sciences of the United States of America Vol. 103(39), pp. 14637-41 |
article | DOI URL |
Abstract: Intensive mechanized agriculture in the Brazilian Amazon grew by textgreater3.6 million hectares (ha) during 2001-2004. Whether this cropland expansion resulted from intensified use of land previously cleared for cattle ranching or new deforestation has not been quantified and has major implications for future deforestation dynamics, carbon fluxes, forest fragmentation, and other ecosystem services. We combine deforestation maps, field surveys, and satellite-based information on vegetation phenology to characterize the fate of large (textgreater25-ha) clearings as cropland, cattle pasture, or regrowing forest in the years after initial clearing in Mato Grosso, the Brazilian state with the highest deforestation rate and soybean production since 2001. Statewide, direct conversion of forest to cropland totaled textgreater540,000 ha during 2001-2004, peaking at 23% of 2003 annual deforestation. Cropland deforestation averaged twice the size of clearings for pasture (mean sizes, 333 and 143 ha, respectively), and conversion occurred rapidly; textgreater90% of clearings for cropland were planted in the first year after deforestation. Area deforested for cropland and mean annual soybean price in the year of forest clearing were directly correlated (R(2) = 0.72), suggesting that deforestation rates could return to higher levels seen in 2003-2004 with a rebound of crop prices in international markets. Pasture remains the dominant land use after forest clearing in Mato Grosso, but the growing importance of larger and faster conversion of forest to cropland defines a new paradigm of forest loss in Amazonia and refutes the claim that agricultural intensification does not lead to new deforestation. | |||||
BibTeX:
@article{morton_cropland_2006, author = {Morton, D. C. and DeFries, R. S. and Shimabukuro, Y. E. and Anderson, L. O. and Arai, E. and del Bon Espirito-Santo, F. and Freitas, R. and Morisette, J.}, title = {Cropland expansion changes deforestation dynamics in the southern Brazilian Amazon}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2006}, volume = {103}, number = {39}, pages = {14637--41}, note = {Edition: 2006/09/16}, url = {http://www.ncbi.nlm.nih.gov/pubmed/16973742}, doi = {https://doi.org/10.1073/pnas.0606377103} } |
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Morton, D.C., Defries, R.S., Randerson, J.T., Giglio, L., Schroeder, W. and van der Werf, G.R. | Agricultural intensification increases deforestation fire activity in Amazonia | 2008 | Global Change Biology Vol. 14(10), pp. 2262-2275 |
article | DOI URL |
Abstract: Fire-driven deforestation is the major source of carbon emissions from Amazonia. Recent expansion of mechanized agriculture in forested regions of Amazonia has increased the average size of deforested areas, but related changes in fire dynamics remain poorly characterized. We estimated the contribution of fires from the deforestation process to total fire activity based on the local frequency of active fire detections from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors. High-confidence fire detections at the same ground location on 2 or more days per year are most common in areas of active deforestation, where trunks, branches, and stumps can be piled and burned many times before woody fuels are depleted. Across Amazonia, high-frequency fires typical of deforestation accounted for more than 40% of the MODIS fire detections during 2003-2007. Active deforestation frontiers in Bolivia and the Brazilian states of Mato Grosso, Para, and Rondonia contributed 84% of these high-frequency fires during this period. Among deforested areas, the frequency and timing of fire activity vary according to postclearing land use. Fire usage for expansion of mechanized crop production in Mato Grosso is more intense and more evenly distributed throughout the dry season than forest clearing for cattle ranching (4.6 vs. 1.7 fire days per deforested area, respectively), even for clearings textgreater 200 ha in size. Fires for deforestation may continue for several years, increasing the combustion completeness of cropland deforestation to nearly 100% and pasture deforestation to 50-90% over 1-3-year timescales typical of forest conversion. Our results demonstrate that there is no uniform relation between satellite-based fire detections and carbon emissions. Improved understanding of deforestation carbon losses in Amazonia will require models that capture interannual variation in the deforested area that contributes to fire activity and variable combustion completeness of individual clearings as a function of fire frequency or other evidence of postclearing land use. | |||||
BibTeX:
@article{morton_agricultural_2008, author = {Morton, D. C. and Defries, R. S. and Randerson, J. T. and Giglio, L. and Schroeder, W. and van der Werf, G. R.}, title = {Agricultural intensification increases deforestation fire activity in Amazonia}, journal = {Global Change Biology}, year = {2008}, volume = {14}, number = {10}, pages = {2262--2275}, url = {://WOS:000259360500004 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2008.01652.x/asset/j.1365-2486.2008.01652.x.pdf?v=1&t=h6hwh2w4&s=9ce856e2db97a0db464363f561c5cc3ab0115007}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01652.x} } |
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Morton, D.C., DeFries, R.S., Nagol, J., Souza Jr., C.M., Kasischke, E.S., Hurtt, G.C. and Dubayah, R. | Mapping canopy damage from understory fires in Amazon forests using annual time series of Landsat and MODIS data | 2011 | Remote Sensing of Environment Vol. 115(7), pp. 1706-1720 |
article | DOI URL |
Abstract: Understory fires in Amazon forests alter forest structure, species composition, and the likelihood of future disturbance. The annual extent of fire-damaged forest in Amazonia remains uncertain due to difficulties in separating burning from other types of forest damage in satellite data. We developed a new approach, the Burn Damage and Recovery (BDR) algorithm, to identify fire-related canopy damages using spatial and spectral information from multi-year time series of satellite data. The BDR approach identifies understory fires in intact and logged Amazon forests based on the reduction and recovery of live canopy cover in the years following fire damages and the size and shape of individual understory burn scars. The BDR algorithm was applied to time series of Landsat (1997-2004) and MODIS (2000-2005) data covering one Landsat scene (path/row 226/068) in southern Amazonia and the results were compared to field observations, image-derived burn scars, and independent data on selective logging and deforestation. Landsat resolution was essential for detection of burn scars textless 50 ha, yet these small burns contributed only 12% of all burned forest detected during 1997-2002. MODIS data were suitable for mapping medium (50-500 ha) and large (textgreater 500 ha) burn scars that accounted for the majority of all fire-damaged forests in this study. Therefore, moderate resolution satellite data may be suitable to provide estimates of the extent of fire-damaged Amazon forest at a regional scale. In the study region, Undsat-based understory fire damages in 1999 (1508 km(2)) were an order of magnitude higher than during the 1997-1998 El Nino event (124 km(2) and 39 km(2), respectively), suggesting a different link between climate and understory fires than previously reported for other Amazon regions. The results in this study illustrate the potential to address critical questions concerning climate and fire risk in Amazon forests by applying the BDR algorithm over larger areas and longer image time series. Published by Elsevier Inc. | |||||
BibTeX:
@article{morton_mapping_2011, author = {Morton, Douglas C. and DeFries, Ruth S. and Nagol, Jyoteshwar and Souza, Jr., Carlos M. and Kasischke, Eric S. and Hurtt, George C. and Dubayah, Ralph}, title = {Mapping canopy damage from understory fires in Amazon forests using annual time series of Landsat and MODIS data}, journal = {Remote Sensing of Environment}, year = {2011}, volume = {115}, number = {7}, pages = {1706--1720}, url = {://WOS:000290506600009}, doi = {https://doi.org/10.1016/j.rse.2011.03.002} } |
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Morton, D. | Forest Carbon Fluxes, a Satellite Perspective [BibTeX] |
2016 | Nature Climate Change Vol. 6, pp. 346-348 |
article | DOI |
BibTeX:
@article{morton_forest_2016, author = {Morton, D.C.}, title = {Forest Carbon Fluxes, a Satellite Perspective}, journal = {Nature Climate Change}, year = {2016}, volume = {6}, pages = {346--348}, doi = {https://doi.org/10.1038/nclimate2978} } |
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Morton, D.C., Macedo, M.M., Gibbs, H.K., Victoria, D.C., Bolfe, E.L. and Noojipady, P. | Reevaluating suitability estimates based on dynamics of cropland expansion in the Brazilian Amazon [BibTeX] |
2016 | Global Environmental Change-Human and Policy Dimensions Vol. 37, pp. 92-101 |
article | |
BibTeX:
@article{morton_dc_reevaluating_2016, author = {Morton D.C., Macedo M.M., Gibbs H.K., Victoria D.C., Bolfe E.L., Noojipady P.}, title = {Reevaluating suitability estimates based on dynamics of cropland expansion in the Brazilian Amazon}, journal = {Global Environmental Change-Human and Policy Dimensions}, year = {2016}, volume = {37}, pages = {92--101} } |
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Mortarini, L., Katul, G.G., Cava, D., Dias-Junior, C.Q., Dias, N.L., Manzi, A., Sorgel, M., Araújo, A. and Chamecki, M. | Adjustments to the law of the wall above an Amazon forest explained by a spectral link [BibTeX] |
2023 | Physics of Fluids Vol. 35(2), pp. 025102 |
article | DOI URL |
BibTeX:
@article{mortarini_adjustments_2023, author = {Mortarini, Luca and Katul, Gabriel G. and Cava, Daniela and Dias-Junior, Cleo Quaresma and Dias, Nelson Luis and Manzi, Antonio and Sorgel, Matthias and Araújo, Alessandro and Chamecki, Marcelo}, title = {Adjustments to the law of the wall above an Amazon forest explained by a spectral link}, journal = {Physics of Fluids}, year = {2023}, volume = {35}, number = {2}, pages = {025102}, url = {https://doi.org/10.1063/5.0135697}, doi = {https://doi.org/10.1063/5.0135697} } |
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Mortarini, L., Dias-Júnior, C.Q., Acevedo, O., Oliveira, P.E.S., Tsokankunku, A., Sörgel, M., Manzi, A.O., de Araújo, A.C., Brondani, D.V., Toro, I.M.C., Giostra, U. and Cava, D. | Vertical propagation of submeso and coherent structure in a tall and dense amazon forest in different stability conditions. PART II: Coherent structures analysis | 2022 | Agricultural and Forest Meteorology Vol. 322, pp. 108993 |
article | DOI URL |
Abstract: Observations of the vertical structure of the turbulent flow in different stability regimes above and within the Amazon Forest at the Amazon Tall Tower Observatory (ATTO) site have been presented in Part I. Here, the influence of stability on the inception and development of coherent structures is investigated. According to the mixing-layer analogy the coherent vortices that dominate the turbulent flows at the canopy-atmosphere interface are generated by hydrodynamical instabilities triggered by an inflection in the vertical profile of the mean wind speed at or near the canopy top. The coherent motions time, Tpeak and separation length scale, Λ, depend on the shear length scale, Ls, close to the canopy top. The present analysis studies the characteristics of Ls, Tpeak and Λ in the five stability regimes defined in Part I. The behaviour of Ls with stability is evaluated and parameterized. Ls increases with decreasing stability, presenting two asymptotes for large unstable and stable stratification and a linear behaviour close to neutral stratification. Coherent structures and their timescale are detected with an original method based on the autocorrelation functions of 5-min subsets of turbulent quantities. The vertical time scale is larger in neutral conditions and decreases for both increasing and decreasing stability. At the canopy top the separation length scale presents a linear dependence on Ls, whose slope is maximum in neutral conditions and decreases departing from neutrality. An original parameterization of the dependence of this slope on h/L, where h is the canopy height and L is the Obukhov length, is shown. Combining the parameterizations, the dependence of the separation length scale is finally presented. Λ has a maximum for slightly unstable conditions, linearly decreases towards neutral and weakly stable stratifications and then it tends to zero for very intense unstable and stable stratifications. | |||||
BibTeX:
@article{mortarini_vertical_2022, author = {Mortarini, Luca and Dias-Júnior, Cléo Q. and Acevedo, Otávio and Oliveira, Pablo E. S. and Tsokankunku, Anywhere and Sörgel, Matthias and Manzi, Antônio Ocimar and de Araújo, Alessandro C. and Brondani, Daiane V. and Toro, Ivan Mauricio Cely and Giostra, Umberto and Cava, Daniela}, title = {Vertical propagation of submeso and coherent structure in a tall and dense amazon forest in different stability conditions. PART II: Coherent structures analysis}, journal = {Agricultural and Forest Meteorology}, year = {2022}, volume = {322}, pages = {108993}, url = {https://www.sciencedirect.com/science/article/pii/S0168192322001836}, doi = {https://doi.org/10.1016/j.agrformet.2022.108993} } |
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Morisette, J.T., Giglio, L., Csiszar, I., Setzer, A., Schroeder, W., Morton, D. and Justice, C.O. | Validation of MODIS active fire detection products derived from two algorithms | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Fire influences global change and tropical ecosystems through its connection to land-cover dynamics, atmospheric composition, and the global carbon cycle. As such, the climate change community, the Brazilian government, and the Large-Scale Biosphere - Atmosphere (LBA) Experiment in Amazonia are interested in the use of satellites to monitor and quantify fire occurrence throughout Brazil. Because multiple satellites and algorithms are being utilized, it is important to quantify the accuracy of the derived products. In this paper the characteristics of two fire detection algorithms are evaluated, both of which are applied to Terra's Moderate Resolution Imagine Spectroradiometer ( MODIS) data and with both operationally producing publicly available fire locations. The two algorithms are NASA's operational Earth Observing System (EOS) MODIS fire detection product and Brazil's Instituto Nacional de Pesquisas Espaciais (INPE) algorithm. Both algorithms are compared to fire maps that are derived independently from 30-m spatial resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer ( ASTER) imagery. A quantitative comparison is accomplished through logistic regression and error matrices. Results show that the likelihood of MODIS fire detection, for either algorithm, is a function of both the number of ASTER fire pixels within the MODIS pixel as well as the contiguity of those pixels. Both algorithms have similar omission errors and each has a fairly high likelihood of detecting relatively small fires, as observed in the ASTER data. However, INPE's commission error is roughly 3 times more than that of the EOS algorithm. | |||||
BibTeX:
@article{morisette_validation_2005, author = {Morisette, Jeffrey T. and Giglio, Louis and Csiszar, Ivan and Setzer, Alberto and Schroeder, Wilfrid and Morton, Douglas and Justice, Christopher O.}, title = {Validation of MODIS active fire detection products derived from two algorithms}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241213200001} } |
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Morgan, W., Allan, J.D., Flynn, M., Darbyshire, E., Hodgson, A., Johnson, B.T., Haywood, J.M., Freitas, S., Longo, K., Artaxo, P. and Coe, H. | Overview of the South American biomass burning analysis (SAMBBA) field experiment [BibTeX] |
2013 | Nucleation and Atmospheric Aerosols(1527), pp. 587-590 | article | DOI |
BibTeX:
@article{morgan_overview_2013, author = {Morgan, W.T. and Allan, J. D. and Flynn, M. and Darbyshire, E. and Hodgson, A. and Johnson, B. T. and Haywood, J. M. and Freitas, S. and Longo, K. and Artaxo, P. and Coe, H.}, title = {Overview of the South American biomass burning analysis (SAMBBA) field experiment}, journal = {Nucleation and Atmospheric Aerosols}, year = {2013}, number = {1527}, pages = {587--590}, note = {Edition: Ed. Paul DeMott and Colin D. O´Dowd. AIP Conf. Proc.}, doi = {https://doi.org/10.1063/1.4803339} } |
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Morgan, W.T., Allan, J.D., Bauguitte, S., Darbyshire, E., Flynn, M.J., Lee, J., Liu, D., Johnson, B., Haywood, J., Longo, K.M., Artaxo, P.E. and Coe, H. | Transformation and aging of biomass burning carbonaceous aerosol over tropical South America from aircraft in-situ measurements during SAMBBA [BibTeX] |
2019 | Atmospheric Chemistry And Physics Discussion Vol. 19, pp. 1-32 |
article | |
BibTeX:
@article{morgan_transformation_2019, author = {Morgan, William T. and Allan, James D. and Bauguitte, Stéphane and Darbyshire, Eoghan and Flynn, Michael J. and Lee, James and Liu, Dantong and Johnson, Ben and Haywood, Jim and Longo, Karla M. and Artaxo, Paulo E. and Coe, Hugh}, title = {Transformation and aging of biomass burning carbonaceous aerosol over tropical South America from aircraft in-situ measurements during SAMBBA}, journal = {Atmospheric Chemistry And Physics Discussion}, year = {2019}, volume = {19}, pages = {1--32} } |
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Moreira, M.Z., Sternberg, L.D.L. and Nepstad, D.C. | Vertical patterns of soil water uptake by plants in a primary forest and an abandoned pasture in the eastern Amazon: an isotopic approach | 2000 | Plant and Soil Vol. 222(1-2), pp. 95-107 |
article | DOI URL |
Abstract: This study evaluated the water uptake patterns of a primary forest and of the savanna-like vegetation of an abandoned pasture in an eastern Amazon site. We used natural stable isotope abundance in the soil profile, as well as plots irrigated with deuterated water to determine time and depth of soil water uptake by plants in different functional groups. Natural isotopic abundance was not suitable for identification of depth of water uptake by plants, but experiments using labeled water were. We found that the label percolation rate in the soil profile of the forest was lower than that observed in the pasture. Fourteen months after application, the label peak was located at 1.8 m depth in the forest and at 3 m depth in the pasture. Isotopic analysis of sap water from trees and lianas in the forest during the dry season showed that trees acquired labeled water at a deeper level in the soil profile compared to that acquired by lianas. Depth of water uptake by lianas seems to vary on a seasonal basis. In the pasture the 'colonizer' shrub (Solanum crinitum Lamb.) took up labeled water only from the surface layer of the soil profile (similar to 20%), whereas the most abundant coexisting grass (Panicum maximum Jacq.) acquired it from the top meter. None of the pasture plants were able to acquire labeled water after one rainy season when the label pulse was deep in the soil (textgreater 1 m deep). These results have implications for studies of forest water cycle in which the soil volume used as source of water for plant transpiration is still unknown, and for an understanding of plant succession in the forest regeneration process of abandoned pastures in the eastern Amazon. | |||||
BibTeX:
@article{moreira_vertical_2000, author = {Moreira, M. Z. and Sternberg, L. D. L. and Nepstad, D. C.}, title = {Vertical patterns of soil water uptake by plants in a primary forest and an abandoned pasture in the eastern Amazon: an isotopic approach}, journal = {Plant and Soil}, year = {2000}, volume = {222}, number = {1-2}, pages = {95--107}, url = {://WOS:000088041000009}, doi = {https://doi.org/10.1023/a:1004773217189} } |
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Moreira, A.A., Adamatti, D.S. and Ruhoff, A.L. | Avaliação dos produtos de evapotranspiração baseados em sensoriamento remoto MOD16 e GLEAM em sítios de fluxos turbulentos do Programa LBA [BibTeX] |
2018 | Ciência e Natura Vol. 40(Edição Especial: X Workshop Brasileiro de Micrometeorologia), pp. 112 - 118 |
article | DOI |
BibTeX:
@article{moreira_avaliacao_2018, author = {Moreira, Adriana Aparecida and Adamatti, Daniela Santini and Ruhoff, Anderson Luis}, title = {Avaliação dos produtos de evapotranspiração baseados em sensoriamento remoto MOD16 e GLEAM em sítios de fluxos turbulentos do Programa LBA}, journal = {Ciência e Natura}, year = {2018}, volume = {40}, number = {Edição Especial: X Workshop Brasileiro de Micrometeorologia}, pages = {112 -- 118}, doi = {https://doi.org/10.5902/2179460X30714} } |
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Moran-Zuloaga, D., Ditas, F., Walter, D., Saturno, J., Brito, J., Carbone, S., Chi, X., Hrabě de Angelis, I., Baars, H., Godoi, R.H.M., Heese, B., Holanda, B.A., Lavrič, J.V., Martin, S.T., Ming, J., Pöhlker, M.L., Ruckteschler, N., Su, H., Wang, Y., Wang, Q., Wang, Z., Weber, B., Wolff, S., Artaxo, P., Pöschl, U., Andreae, M.O. and Pöhlker, C. | Long-term study on coarse mode aerosols in the Amazon rain forest with the frequent intrusion of Saharan dust plumes [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18, pp. 10055-10088 |
article | DOI |
BibTeX:
@article{moran-zuloaga_long-term_2018, author = {Moran-Zuloaga, D. and Ditas, F. and Walter, D. and Saturno, J. and Brito, J. and Carbone, S. and Chi, X. and Hrabě de Angelis, I. and Baars, H. and Godoi, R. H. M. and Heese, B. and Holanda, B. A. and Lavrič, J. V. and Martin, S. T. and Ming, J. and Pöhlker, M. L. and Ruckteschler, N. and Su, H. and Wang, Y. and Wang, Q. and Wang, Z. and Weber, B. and Wolff, S. and Artaxo, P. and Pöschl, U. and Andreae, M. O. and Pöhlker, C.}, title = {Long-term study on coarse mode aerosols in the Amazon rain forest with the frequent intrusion of Saharan dust plumes}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, pages = {10055--10088}, doi = {https://doi.org/10.5194/acp-18-10055-2018} } |
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Moran, E.F., Brondizio, E.S., Tucker, J.M., da Silva-Forsberg, M.C., McCracken, S. and Falesi, I. | Effects of soil fertility and land-use on forest succession in Amazonia | 2000 | Forest Ecology and Management Vol. 139(1-3), pp. 93-108 |
article | DOI URL |
Abstract: This paper examines the role of soil fertility and land-use history on the rates of forest successional regrowth in five regions of the Amazon Basin. Sites are located in the Bragantina Region, Tome Acu Region, Altamira Region and Marajo Region of the State of Para, Brazil and in a region of the Colombian Vaupes. Methods used included vegetation inventories of successional and mature forests, soil sampling, ethnographic assessment of land-use histories, and land cover classification based on multi-temporal Landsat Thematic Mapper digital satellite data. The paper examines inter-regional differences, intraregional differences, and Basin-wide differences in rates of forest regrowth. Inter-regional differences are best explained by the differences between areas in soil fertility, whereas intra-regional differences are best explained by the differential impact of land-use history on forest recovery. Basin-wide differences in rates of succession can best be captured by differences in tree height, and secondarily by differences in basal area. In inter-regional comparisons we found that ultisols, oxisols, and spodosols present similar rates of regrowth, but considerably slower rates when compared to alfisols. During the first 5-10 years of regrowth, alfisol. areas have average stand height 1 m higher, and this difference doubles after 15 years of regrowth. In intra-regional comparisons, using one region as an example, we found that land-use differences are most able to explain differences. Areas that had been in swidden agriculture grew back at a rate of 1.5 m per year; as compared with 0.45 m per year for areas that had experienced mechanized land preparation, and 0.62 m per year for areas that had been in pasture. In Basin-wide comparisons we have been able to discriminate three distinct stages of secondary succession using structural criteria, across both soil and land-use types with height as the most predictive criteria of overall structural development. By comparing our five sites' data with that of other investigators, the paper proposes Basin-wide patterns of regrowth for each of three structural stages of secondary succession that facilitate linking the field vegetation data to remotely-sensed data of land cover. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{moran_effects_2000, author = {Moran, E. F. and Brondizio, E. S. and Tucker, J. M. and da Silva-Forsberg, M. C. and McCracken, S. and Falesi, I.}, title = {Effects of soil fertility and land-use on forest succession in Amazonia}, journal = {Forest Ecology and Management}, year = {2000}, volume = {139}, number = {1-3}, pages = {93--108}, url = {://WOS:000166242100007}, doi = {https://doi.org/10.1016/s0378-1127(99)00337-0} } |
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Moran, E.F., Brondízio, E. and Batistella, M. | Trajetórias de Desmatamento e Uso da terra na Amazônia Brasileira: Uma Análise Multiescalar [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 55-70 |
incollection | |
BibTeX:
@incollection{batistella_trajetorias_2008, author = {Moran, Emilio F. and Brondízio, Eduardo and Batistella, Mateus}, title = {Trajetórias de Desmatamento e Uso da terra na Amazônia Brasileira: Uma Análise Multiescalar}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {55--70}, note = {Section: 2} } |
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Moran, E.F., Adams, R., Bakoyema, B., Stefano Fiorini, T and Boucek, B. | Human strategies for coping with El Nino related drought in Amazonia | 2006 | Climatic Change Vol. 77(3-4), pp. 343-361 |
article | DOI URL |
Abstract: This article reports on findings of a research project examining farmers' coping strategies in the Brazilian Amazon in response to El Nino related weather events. We examine the extent of vulnerability of small and large farmers to these events in a tropical rainforest environment. Little attention has been given to the impact of ENSO events in Amazonia, despite evidence for devastating fires during ENSOs. Although we found a range of locally developed forecasting techniques and coping mechanisms, farmers have sustained significant losses, and we suggest that increased access to scientific forecasts would greatly enhance the ability of the farmers in our study area to cope with El Nino related weather events. In Amazonia the El Nino phase of the El Nino-Southern Oscillation (ENSO) climate pattern leads to an extended period of reduced rainfall (Hobbs et al., 1998). This period of reduced rainfall can result in significant agricultural losses for farmers and ranchers in the area and in increased forest flammability. We have found that the majority of our study population uses several methods of forecasting, coping with, and adapting to drought events - and they recognize the economic losses they can experience and the loss of forests through the accidental spread of fire. The poorest farmers in our study area experience El Nino related drought events as a serious threat to their livelihoods. Their vulnerability is heightened during extreme climate events and our observations revealed that all of the farmers in our study would benefit from increased availability of improved forecast information relevant to their locality and their current farming strategies. This paper examines the availability and use of forecasts, the occurrence of accidental fires and techniques to prevent fire related losses, and the coping mechanisms for dealing with El Nino related drought in the agricultural regions surrounding the cities of Altamira and Santarem, in Para State, Brazil. Distribution of an El Nino Prediction Kit at the end of the study and a series of workshops may lead to better local information on rainfall variability and create a farmer-maintained grid of collecting stations to sensitize farmers to the variability of precipitation in the region, and on their property. | |||||
BibTeX:
@article{moran_human_2006, author = {Moran, Emilio F. and Adams, Ryan and Bakoyema, Bryn and T, Stefano Fiorini and Boucek, Bruce}, title = {Human strategies for coping with El Nino related drought in Amazonia}, journal = {Climatic Change}, year = {2006}, volume = {77}, number = {3-4}, pages = {343--361}, url = {://WOS:000240307600011}, doi = {https://doi.org/10.1007/s10584-005-9035-9} } |
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Morales, J.E. and Poveda, G. | Diurnally driven scaling properties of Amazonian rainfall fields: Fourier spectra and order-q statistical moments | 2009 | Journal of Geophysical Research-Atmospheres Vol. 114 |
article | DOI URL |
Abstract: The influence of the diurnal cycle on spatial scaling properties of Amazonian rainfall fields is investigated using data gathered during the January-February 1999 Wet Season Atmospheric Meso-scale Campaign in the state of Rondonia (Brazil, SW Amazonia). Most intense precipitation events with large spatial coverage occur during early afternoon. Amplitudes of average and maximum intensity diurnal cycles are higher during the easterly than during the westerly atmospheric regime. The diurnal cycle of average rainfall occupancy exhibits a significantly larger amplitude during the westerly regime. Storms exhibit power law Fourier spectra, E(k) = ck(-beta), with two scaling regimes characterized by different scaling exponents (beta(1) and beta(2)), separated at a critical distance, which depends on the spatial extent of rainfall organization. Inversely correlated diurnal cycles for beta(1) and beta(2) reflect rainfall organization patterns at different spatial scales through the 24-h period. The break occurs at smaller (larger) spatial scales during the morning (afternoon-evening). Average values of c and beta exhibit inversely related diurnal cycles, and different behavior during either atmospheric regime. Order-q statistical moments indicate multiscaling of rainfall fields. Departures from simple scaling are also driven by the diurnal cycle, reflecting differences in convective activity and the spatial organization of rainfall throughout the 24-h cycle. Departures from simple scaling are dependent on the moment order q. Clear-cut differences between the estimated order-q statistical moments appear during both atmospheric regimes. These results shed light toward linking physical processes with statistics in Amazonian storms. | |||||
BibTeX:
@article{morales_diurnally_2009, author = {Morales, Julian E. and Poveda, German}, title = {Diurnally driven scaling properties of Amazonian rainfall fields: Fourier spectra and order-q statistical moments}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2009}, volume = {114}, url = {://WOS:000266742300002}, doi = {https://doi.org/10.1029/2008jd011281} } |
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Morais, V., Dambros, C., Tapia-Coral, S.C., Acioly A., J.W. and Oliveira | Mesofauna do solo em diversos sistemas de uso da terra no Alto Rio Solimões, AM [BibTeX] |
2010 | Neotropical Entomology Vol. 39, pp. 145-152 |
article | |
BibTeX:
@article{morais_mesofauna_2010, author = {Morais, V.S. ; Dambros, C.S.; Sandra C Tapia-Coral ; Acioly, A., José W.; Oliveira}, title = {Mesofauna do solo em diversos sistemas de uso da terra no Alto Rio Solimões, AM}, journal = {Neotropical Entomology}, year = {2010}, volume = {39}, pages = {145--152} } |
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Morais, F.G., Franco, M.A., Palácios, R., Machado, L.A.T., Rizzo, L.V., Barbosa, H.M.J., Jorge, F., Schafer, J.S., Holben, B.N., Landulfo, E. and Artaxo, P. | Relationship between Land Use and Spatial Variability of Atmospheric Brown Carbon and Black Carbon Aerosols in Amazonia | 2022 | Atmosphere Vol. 13(8) |
article | DOI |
Abstract: The aerosol radiative effect is an important source of uncertainty in estimating the anthropogenic impact of global climate change. One of the main open questions is the role of radiation absorption by aerosols and its relation to land use worldwide, particularly in the Amazon Rainforest. Using AERONET (Aerosol Robotic Network) long-term measurements of aerosol optical depth (AOD) at a wavelength of 500 nm and absorption AOD (AAOD) at wavelengths of 440, 675, and 870 nm, we estimated the fraction and seasonality of the black carbon (BC) and brown carbon (BrC) contributions to absorption at 440 nm. This was conducted at six Amazonian sites, from central Amazon (Manaus and the Amazon Tall Tower Observatory—ATTO) to the deforestation arc (Rio Branco, Cuiabá, Ji-Paraná, and Alta Floresta). In addition, land use and cover data from the MapBiomas collection 6.0 was used to access the land transformation from forest to agricultural areas on each site. The results showed, for the first time, important geographical and seasonal variability in the aerosol optical properties, particularly the BC and BrC contributions. We observed a clear separation between dry and wet seasons, with BrC consistently accounting for an average of approximately 12% of the aerosol AAOD at 440 nm in the deforestation arc. In central Amazon, the contribution of BrC was approximately 25%. A direct relationship between the reduction in forests and the increase in the area dedicated to agriculture was detected. Moreover, places with lower fractions of forest had a smaller fraction of BrC, and regions with higher fractions of agricultural areas presented higher fractions of BC. Therefore, significant changes in AOD and AAOD are likely related to land-use transformations and biomass burning emissions, mainly during the dry season. The effects of land use change could introduce differences in the radiative balance in the different Amazonian regions. The analyses presented in this study allow a better understanding of the role of aerosol emissions from the Amazon Rainforest that could have global impacts. | |||||
BibTeX:
@article{morais_relationship_2022, author = {Morais, Fernando G. and Franco, Marco A. and Palácios, Rafael and Machado, Luiz A. T. and Rizzo, Luciana V. and Barbosa, Henrique M. J. and Jorge, Fabio and Schafer, Joel S. and Holben, Brent N. and Landulfo, Eduardo and Artaxo, Paulo}, title = {Relationship between Land Use and Spatial Variability of Atmospheric Brown Carbon and Black Carbon Aerosols in Amazonia}, journal = {Atmosphere}, year = {2022}, volume = {13}, number = {8}, doi = {https://doi.org/10.3390/atmos13081328} } |
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Moraes, O.L.L., Fitzjarrald, D.R., Acevedo, O.C., Sakai, R.K., Czikowsky, M.J. and Degrazia, G.A. | Comparing spectra and cospectra of turbulence over different surface boundary conditions | 2008 | Physica a-Statistical Mechanics and Its Applications Vol. 387(19-20), pp. 4927-4939 |
article | DOI URL |
Abstract: Long-term eddy-covariance measurements from the LBA-ECO Project were used to study the behavior of turbulence spectra and cospectra above the Amazon rainforest as well as over a nearby deforested area in the central part of Amazon region. Results are separated according to the wind speed and stability conditions. Under stable low wind speed conditions the Kolmogorov inertial subrange law is not observed. For all other situations simple empirical relations are obtained and length scales associated with the more energetic eddies are calculated. Above the forest canopy, the cospectra are more peaked than those observed over the deforested area, confirming previous observations made over a midlatitude forest. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{moraes_comparing_2008, author = {Moraes, Osvaldo L. L. and Fitzjarrald, David R. and Acevedo, Otavio C. and Sakai, Ricardo K. and Czikowsky, Matthew J. and Degrazia, Gervasio A.}, title = {Comparing spectra and cospectra of turbulence over different surface boundary conditions}, journal = {Physica a-Statistical Mechanics and Its Applications}, year = {2008}, volume = {387}, number = {19-20}, pages = {4927--4939}, url = {://WOS:000257967800022}, doi = {https://doi.org/10.1016/j.physa.2008.04.007} } |
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Moraes Novo, E.M.L., de Farias Barbosa, C.C., de Freitas, R.M., Shimabukuro, Y.E., Melack, J.M. and Pereira, W.F. | Seasonal changes in chlorophyll distributions in Amazon floodplain lakes derived from MODIS images | 2006 | Limnology Vol. 7(3), pp. 153-161 |
article | DOI URL |
Abstract: To assess seasonal changes in phytoplanktonic chlorophyll distributions in Amazon floodplain lakes, a linear mixing model was applied to Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data acquired at four river stages: rising (April), high (June), decreasing (September), and low (November). The study area is located in a floodplain reach from Parintins (Amazonas) to near Almeirim (Para). A three-end-member mixing model designed to uncouple three fractions [high suspended inorganic matter (ip), low inorganic suspended matter (w), and high chlorophyll a (Chl)] was tested in Lake Curuai (1.5 degrees S 55.43 degrees W) based on field sampling done almost concurrently with satellite overpasses. During high water, phytoplankton patches are confined to lakes closer to terra firme under the influence of clear water inflow, whereas during the low and decreasing water stages, the patches are more evenly distributed over the floodplain. | |||||
BibTeX:
@article{moraes_novo_seasonal_2006, author = {Moraes Novo, Evlyn Marcia Leao and de Farias Barbosa, ClAudio Clemente and de Freitas, Ramon Moraes and Shimabukuro, Yosio Edimir and Melack, John M. and Pereira, Waterloo Filho}, title = {Seasonal changes in chlorophyll distributions in Amazon floodplain lakes derived from MODIS images}, journal = {Limnology}, year = {2006}, volume = {7}, number = {3}, pages = {153--161}, url = {://WOS:000242770900002}, doi = {https://doi.org/10.1007/s10201-006-0179-8} } |
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Moraes, J.M., Schuler, A.E., Dunne, T., Figueiredo, R.d.O. and Victoria, R.L. | Water storage and runoff processes in plinthic soils under forest and pasture in Eastern Amazonia | 2006 | Hydrological Processes Vol. 20(12), pp. 2509-2526 |
article | DOI URL |
Abstract: Extensive areas of the Amazon River basin are underlain by soils with shallow impeding horizons. To evaluate how the distinctive hydraulic properties of soil with a plinthic horizon under forest and pasture affect water storage and runoff process, two first-order catchments drained by ephemeral streams were instrumental in eastern Amazonia. Field measurements showed the presence of a strong vertical gradient of saturated hydraulic conductivity, which declines to extremely low values (median textless1 rum h(-1)) at the plinthite layer, limiting both vertical and lateral flow, and keeping the soil water content close to saturation throughout most of the wet season. This scenario led to the frequent occurrence of saturation overland flow (SOF) under both land covers and very small amounts of shallow sub-surface flow (SSF). The annual flow in the exit channels was 3.2% of throughfall (2.7% of annual rainfall) under forest and 17% of annual rainfall for pasture, while the frequency of days with overland flow (OVF) was about 60% of the days for both catchments during the wet season. In the forest, all OVF originated from saturated areas, while in the pasture, infiltration-excess OVF accounted for 40% of the runoff and SOF accounted for 55% of runoff. The higher flow generation in the pasture could be explained by the higher water storage compared to the forest, promoting more frequent SOF, and additionally by the lower hydraulic conductivity near the surface favouring the occurrence of Horton overland flow (HOF). Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{moraes_water_2006, author = {Moraes, Jorge M. and Schuler, Azeneth E. and Dunne, Thomas and Figueiredo, Ricardo de O. and Victoria, Reynaldo L.}, title = {Water storage and runoff processes in plinthic soils under forest and pasture in Eastern Amazonia}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2509--2526}, url = {://WOS:000239670800004}, doi = {https://doi.org/10.1002/hyp.6213} } |
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Moraes, E.T.I., Dias-Júnior, C.Q., Cohen, J.C.P., Corrêa, P.B., Martins, H.S., D'Oliveira, F.A.F., Kuhn, P.A., Cattanio, J.H., Souza, E.B., de Araújo, A.C., Teixeira, P.R. and Mortarini, L. | Simulation of an orographic gravity wave above the Amazon rainforest and its influence on gases transport near the surface | 2022 | Atmospheric Research Vol. 278, pp. 106349 |
article | DOI URL |
Abstract: The influence of the topography at the ATTO site (Amazon Tall Tower Observatory) in the formation of Gravity Waves (GW) was investigated in this work. The role of these waves in gas transport on different heights in the nocturnal boundary layer, was also investigated. For this, were analyzed: experimental data of wind speed, temperature, humidity and CO2 to identify the GW. Furthermore satellite images, ECMWF ERA5 (European Center for Medium-Range Weather Forecasts) reanalysis, and numerical simulations from the mesoscale JULES-CCATT-BRAMS model (Brazilian Regional Atmospheric Modeling System) version 5.3 were used to perform GW simulations. The simulations involved two configurations (Control-With Topography and No Topography). The sattelite images made it clear that the GW was not associated with convective activities. The simulations showed clear ondulatory signs in air temperature, vertical component of the wind, and gases like CO and O3. Moreover, they also reveal that the wave originated by the presence of the local topography and this orograph gravity wave had and important role in the transport of gases above the ATTO site. | |||||
BibTeX:
@article{moraes_simulation_2022, author = {Moraes, Eiky T. I. and Dias-Júnior, Cléo Q. and Cohen, Júlia C. P. and Corrêa, Polari B. and Martins, Hardiney S. and D'Oliveira, Flávio A. F. and Kuhn, Paulo A. and Cattanio, José H. and Souza, Everaldo B. and de Araújo, Alessandro C. and Teixeira, Paulo R. and Mortarini, Luca}, title = {Simulation of an orographic gravity wave above the Amazon rainforest and its influence on gases transport near the surface}, journal = {Atmospheric Research}, year = {2022}, volume = {278}, pages = {106349}, url = {https://www.sciencedirect.com/science/article/pii/S0169809522003350}, doi = {https://doi.org/10.1016/j.atmosres.2022.106349} } |
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Moraes, C., J.M.N., C., A.C.L., C., Silva-Dias, M.H., M.A.F., C., J.C.P., G. and B.C., A.W. | Variação espacial e temporal da precipitação no estado do Pará. Interações entre nuvens, chuvas e a biosfera na Amazônia [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 207-214 |
article | |
BibTeX:
@article{moraes_variacao_2005, author = {Moraes, Costa, J.M.N., Costa, A.C.L., Costa, M.H., Silva-Dias, M.A.F., Cohen, J.C.P., Gandú, A.W., B.C.}, title = {Variação espacial e temporal da precipitação no estado do Pará. Interações entre nuvens, chuvas e a biosfera na Amazônia}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {207--214} } |
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Montes, C.R., Lucas, Y., Pereira, O.J.R., Achard, R., Grimaldi, M. and Melfi, A.J. | Deep plant-derived carbon storage in Amazonian podzols | 2011 | Biogeosciences Vol. 8(1), pp. 113-120 |
article | DOI URL |
Abstract: Equatorial podzols are soils characterized by thick sandy horizons overlying more clayey horizons. Organic matter produced in the topsoil is transferred in depth through the sandy horizons and accumulate at the transition, at a depth varying from 1 to more than 3 m, forming deep horizons rich in organic matter (Bh horizons). Although they cover great surfaces in the equatorial zone, these soils are still poorly known. Studying podzols from Amazonia, we found out that the deep Bh horizons in poorly drained podzol areas have a thickness higher than 1m and store unexpected amounts of carbon. The average for the studied area was 66.7 +/- 5.8 kgCm(-2) for the deep Bh and 86.8 +/- 7.1 kgCm(-2) for the whole profile. Extrapolating to the podzol areas of the whole Amazonian basin has been possible thanks to digital maps, giving an order of magnitude around 13.6 +/- 1.1 PgC, at least 12.3 PgC higher than previous estimates. This assessment should be refined by additional investigations, not only in Amazonia but in all equatorial areas where podzols have been identified. Because of the lack of knowledge on the quality and behaviour of the podzol organic matter, the question of the feedback between the climate and the equatorial podzol carbon cycle is open. | |||||
BibTeX:
@article{montes_deep_2011, author = {Montes, C. R. and Lucas, Y. and Pereira, O. J. R. and Achard, R. and Grimaldi, M. and Melfi, A. J.}, title = {Deep plant-derived carbon storage in Amazonian podzols}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {1}, pages = {113--120}, url = {://WOS:000286722500008}, doi = {https://doi.org/10.5194/bg-8-113-2011} } |
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Montero, M., Wittmann F., J. and Piedade | Floristic variation across 600 km of inundation forests (Igapó) along the Negro River, Central Amazonia [BibTeX] |
2014 | Hydrobiologia Vol. 729, pp. 229-246 |
article | |
BibTeX:
@article{montero_floristic_2014, author = {Montero, MTF; Wittmann, F., JC; Piedade}, title = {Floristic variation across 600 km of inundation forests (Igapó) along the Negro River, Central Amazonia}, journal = {Hydrobiologia}, year = {2014}, volume = {729}, pages = {229--246} } |
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Monteiro, R. | Associativismo e fronteira: a Amazônia como espaço de reprodução social da agricultura do Sul [BibTeX] |
2008 | Vol. 1Sociedade, Território e Conflitos: BR-163 em questão, pp. 223-264 |
incollection | |
BibTeX:
@incollection{castro_associativismo_2008, author = {Monteiro, R.}, title = {Associativismo e fronteira: a Amazônia como espaço de reprodução social da agricultura do Sul}, booktitle = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, pages = {223--264} } |
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Monteiro, M.T.F., Tomasella, J., Candido, L. and Luizão, F. | Application of D-SEM to a catchment in Central Amazonia: calibration and validation of the carbon and nitrogen cycles [BibTeX] |
2015 | Ecohydrology & Hydrobiology Vol. 15(4), pp. 192-207 |
article | |
BibTeX:
@article{monteiro_application_2015, author = {Monteiro, M. T. F. and Tomasella, J. and Candido, L.A. and Luizão, F.}, title = {Application of D-SEM to a catchment in Central Amazonia: calibration and validation of the carbon and nitrogen cycles}, journal = {Ecohydrology & Hydrobiology}, year = {2015}, volume = {15}, number = {4}, pages = {192--207} } |
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Monteiro, M.T., Oliveira, S.M., Luizão, F.J., Cândido, L.A., Ishida, F.Y. and Tomasella, J. | Dissolved organic carbon concentration and its relationship to electrical conductivity in the waters of a stream in a forested Amazonian blackwater catchment [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 205-213 |
article | |
BibTeX:
@article{monteiro_dissolved_2014, author = {Monteiro, Maria T.F. and Oliveira, Sylvia M. and Luizão, Flávio J. and Cândido, Luiz A. and Ishida, Françoise Y. and Tomasella, Javier}, title = {Dissolved organic carbon concentration and its relationship to electrical conductivity in the waters of a stream in a forested Amazonian blackwater catchment}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {205--213} } |
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Monteiro, L., Saragoussi, F.J., Conceição, M., França, A.C., M.N.C., Z. and M.T.F., F.B. | ECOSSISTEMA AMAZÔNICO: IMPORTANTE AGENTE PARA O EQUILIBRIO BIOGEOQUÍMICO GLOBAL [BibTeX] |
2014 | , pp. 29p.School: INPA | techreport | |
BibTeX:
@techreport{monteiro_ecossistema_2014, author = {Monteiro, Luizão, F.J., Saragoussi, M., Conceição, A.C., França, M.N.C., Zanchi, F.B., M.T.F.}, title = {ECOSSISTEMA AMAZÔNICO: IMPORTANTE AGENTE PARA O EQUILIBRIO BIOGEOQUÍMICO GLOBAL}, school = {INPA}, year = {2014}, pages = {29p.}, note = {Edition: PRONEX/FAPEAM} } |
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Monteiro, A.L., Souza, C.M. and Barreto, P. | Detection of logging in Amazonian transition forests using spectral mixture models | 2003 | International Journal of Remote Sensing Vol. 24(1), pp. 151-159 |
article | DOI URL |
Abstract: Techniques to detect the area affected by logging in the Amazon basin have yet to be tested on transitional forest environments, which contribute significantly to the total logging in the region. Logging in transitional forests is selective and leaves small clearing in the forests where timber is temporarily stored. These areas, called log landings, can be detected automatically in soil fraction images, generated through linear mixture modelling. Based on a harvesting radius from these log landings, it is possible to estimate the area affected by logging. This method was tested in Amazonian transition forest, using Landsat TM and ETM satellite sensor data from the years 1992, 1996 and 1999. Additionally, a methodology to record areas of old and repeated logging is described. | |||||
BibTeX:
@article{monteiro_detection_2003, author = {Monteiro, A. L. and Souza, C. M. and Barreto, P.}, title = {Detection of logging in Amazonian transition forests using spectral mixture models}, journal = {International Journal of Remote Sensing}, year = {2003}, volume = {24}, number = {1}, pages = {151--159}, url = {://WOS:000180624800011}, doi = {https://doi.org/10.1080/01431160210153994} } |
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Molleri, G.S.F., Novo, E.M.L.d.M. and Kampel, M. | Space-time variability of the Amazon River plume based on satellite ocean color | 2010 | Continental Shelf Research Vol. 30(3-4), pp. 342-352 |
article | DOI URL |
Abstract: Satellite ocean color images were used to determine the space-time variability of the Amazon River plume from 2000-2004. The relationship between sea-surface salinity (SSS) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) absorption coefficient for dissolved and detrital material (a(dg)) (r(2)=0.76, n=30, rmse=0.4) was used to identify the Amazon River plume low-salinity waters (textless34 psu). The plume's spatial information was extracted from satellite bi-weekly time series using two metrics: plume area and plume shape. These metrics identified the seasonal variability of plume dimensions and dispersion patterns. During the study period, the plume showed the largest areas from July to August and the smallest from December to January. The mean annual amplitude and the mean, maximum and minimum plume areas were 1020 x 10(3)km(2), 680 x 10(3)km(2), 1506 x 10(3) km(2) and 268 X 10(3) km(2), respectively. Three main shapes and dispersion pattern periods were identified: (1) flow to the northeastern South American coast, in a narrow band adjacent to the continental shelf, from January to April; (2) flow to the Caribbean region, from April to July; and (3) flow to the Central Equatorial Atlantic Ocean, from August to December. Cross-correlation techniques were used to quantify the relationship between the plume's spatial variability and environmental forcing factors, including Amazon River discharge, wind field and ocean currents. The results showed that (1) river discharge is the main factor influencing plume area variability, (2) the wind field regulates the plume's northwestward flow velocity and residence time near the river mouth, and (3) surface currents have a strong influence over river plume dispersion patterns. (c) 2009 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{molleri_space-time_2010, author = {Molleri, Gustavo S. F. and Novo, Evlyn M. L. de M. and Kampel, Milton}, title = {Space-time variability of the Amazon River plume based on satellite ocean color}, journal = {Continental Shelf Research}, year = {2010}, volume = {30}, number = {3-4}, pages = {342--352}, url = {://WOS:000275771000008}, doi = {https://doi.org/10.1016/j.csr.2009.11.015} } |
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Molina Broquet, G.I.P.C.F.P.B.B.D.B.B.R.M.G.L.V.W.S.C.M.J.W.D.E.and.C.P.L. | On the ability of a global atmospheric inversion to constrain variations of CO2 fluxes over Amazonia [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 8423-8438 |
article | DOI |
BibTeX:
@article{molina_ability_2015, author = {Molina, Broquet, G., Imbach, P., Chevallier, F., Poulter, B., Bonal, D., Burban, B., Ramonet, M., Gatti, L. V., Wofsy, S. C., Munger, J. W., Dlugokencky, E., and Ciais, P., L.}, title = {On the ability of a global atmospheric inversion to constrain variations of CO2 fluxes over Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {8423--8438}, doi = {https://doi.org/10.5194/acp-15-8423-2015} } |
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Mohor, G., Rodriguez, D., Tomasella, J. and Siqueira Júnior, J. | Exploratory analyses for the assessment of climate change impacts on the energy production in an Amazon run-of-river hydropower plant [BibTeX] |
2015 | Journal of Hydrology: Regional Studies Vol. 4, pp. 41-59 |
article | |
BibTeX:
@article{mohor_exploratory_2015, author = {Mohor, G.S. and Rodriguez, D.A. and Tomasella, J. and Siqueira Júnior, J.L.}, title = {Exploratory analyses for the assessment of climate change impacts on the energy production in an Amazon run-of-river hydropower plant}, journal = {Journal of Hydrology: Regional Studies}, year = {2015}, volume = {4}, pages = {41--59} } |
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Mitchard, E.T.A., Feldpausch, T., R. Brienen, R., j. W. Lopez-Gonzalez, Gabriela Monteagudo, A., Baker, T.R., Lewis, S., L. Lloyd, J., Quesada, C., A., Gloor, M., Ter Steege, H., Meir, P., Alvarez, E., Araujo-Murakami, A., Aragão, L.E., Arroyo, L., Aymard, G., Banki, O., Bonal, D., Brown, S., Brown, F.I., Cerón, C.E.C., Moscoso, V., Chave, J., Comiskey, J.A. and al. , e. | Markedly divergent estimates of Amazon forest carbon density from ground plots and satellites [BibTeX] |
2014 | Global Ecology and Biogeography Vol. 23(8), pp. 935-946 |
article | |
BibTeX:
@article{mitchard_markedly_2014, author = {Mitchard, Edward T. A. and Feldpausch, Ted and R. Brienen, Roel and j. W. Lopez-Gonzalez and Gabriela Monteagudo, Abel and Baker, Timothy R. and Lewis, Simon and L. Lloyd, Jon and Quesada, Carlos;A. and Gloor, Manuel and Ter Steege, Hans and Meir, Patrick and Alvarez, Esteban and Araujo-Murakami, Alejandro and Aragão, Luiz E.O.C. and Arroyo, Luzmila and Aymard, Gerardo and Banki, Olaf and Bonal, Damien and Brown, Sandra and Brown, Foster I. and Cerón, Carlos E. Chama and Moscoso, Victor and Chave, Jerome and Comiskey, James A. and al., et}, title = {Markedly divergent estimates of Amazon forest carbon density from ground plots and satellites}, journal = {Global Ecology and Biogeography}, year = {2014}, volume = {23}, number = {8}, pages = {935--946} } |
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Misra, V., Dirmeyer, P.A., Kirtman, B.P., Juang, H.M.H. and Kanamitsu, M. | Regional simulation of interannual variability over South America | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] Three regional climate simulations covering the austral summer season during three contrasting phases of the El Nino-Southern Oscillation cycle were conducted with the Regional Spectral Model (RSM) developed at the National Centers for Environmental Prediction (NCEP). The simulated interannual variability of precipitation over the Amazon River Basin, the Intertropical Convergence Zone, the Pacific and Atlantic Ocean basins, and extratropical South America compare reasonably well with observations. The RSM optimally filters the peturbations about a time-varying base field, thereby enhancing the information content of the global NCEP reanalysis. The model is better than the reanalysis in reproducing the observed interannual variability of outgoing longwave radiation at both high frequencies (3-30 days) and intraseasonal (30-60 days) scales. The low-level jet shows a peak in its speed in 1998 and a minimum in the 1999 simulations. The lag correlation of the jet index with convection over various areas in continental South America indicates that the jet induces precipitation over the Pampas region downstream. A detailed moisture budget was conducted over various subregions. This budget reveals that moisture flux convergence determines most of the interannual variability of precipitation over the Amazon Basin, the Atlantic Intertropical Convergence Zone, and the Nordeste region of Brazil. However, both surface evaporation and surface moisture flux convergence were found to be critical in determining the interannual variability of precipitation over the southern Pampas, Gran Chaco area, and the South Atlantic Convergence Zone. | |||||
BibTeX:
@article{misra_regional_2002, author = {Misra, V. and Dirmeyer, P. A. and Kirtman, B. P. and Juang, H. M. H. and Kanamitsu, M.}, title = {Regional simulation of interannual variability over South America}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180336500001}, doi = {https://doi.org/10.1029/2001jd900216} } |
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Misra, V., Dirmeyer, P.A. and Kirtman, B.P. | A comparative study of two land surface schemes in regional climate integrations over South America | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: A case study comparison using two different land surface models in the Regional Spectral Model (RSM) is presented here. This comparison is motivated from recent studies that show a significant impact of land surface processes on the predictability of precipitation at seasonal to interannual scales. We find in this comparative study that coupled land-atmosphere interactions using the simplified simple biosphere (SSiB) scheme and a two-layer soil (control) model with uniform vegetation fraction yield mixed results. It does not clearly indicate the superiority of one scheme over the other for this particular case. The warmer mean surface temperatures simulated by RSM-SSiB improve the seasonal (January-February-March [JFM]) simulation over Amazon River Basin, along Brazilian Highlands, over Bolivian Plateau, and over central America relative to the control model. However, the RSM-SSiB runs exhibit a strong warm bias in the surface temperature over the subtropics of South America. The mean JFM onshore easterly flow from the tropical Atlantic Ocean and the low-level jet are relatively stronger in the SSiB model. The mean JFM precipitation from the RSM-SSiB model shows an improvement over Guianan Highlands, Venezeulan Llanos, and Amazon River Basin. However, the mean JFM precipitation of the control model over the Caribbean Sea, Central America, and equatorial eastern Pacific Ocean is better than the SSiB model. | |||||
BibTeX:
@article{misra_comparative_2002, author = {Misra, V. and Dirmeyer, P. A. and Kirtman, B. P.}, title = {A comparative study of two land surface schemes in regional climate integrations over South America}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200048}, doi = {https://doi.org/10.1029/2001jd001284} } |
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Mircea, M., Facchini, M.C., Decesari, S., Cavalli, F., Emblico, L., Fuzzi, S., Vestin, A., Rissler, J., Swietlicki, E., Frank, G., Andreae, M.O., Maenhaut, W., Rudich, Y. and Artaxo, P. | Importance of the organic aerosol fraction for modeling aerosol hygroscopic growth and activation: a case study in the Amazon Basin | 2005 | Atmospheric Chemistry and Physics Vol. 5, pp. 3111-3126 |
article | URL |
Abstract: The aerosol in the Amazon basin is dominated throughout the year by organic matter, for the most part soluble in water. In this modeling study, we show how the knowledge of water-soluble organic compounds (WSOC) and the associated physical and chemical properties (e.g. solubility, surface tension, dissociation into ions) affect the hygroscopic growth and activation of the aerosol in this area. The study is based on data obtained during the SMOCC field experiment carried out in Rondonia, Brazil, over a period encompassing the dry (biomass burning) season to the onset of the wet season (September to mid-November, 2002). The comparison of predicted and measured cloud condensation nuclei (CCN) number concentration shows that the knowledge of aerosol WSOC composition in terms of classes of compounds and of their relative molecular weights and acidic properties may be sufficient to predict aerosol activation, without any information on solubility. Conversely, the lack of knowledge on WSOC solubility leads to a high overestimation of the observed diameter growth factors (DGF) by the theory. Moreover, the aerosol water soluble inorganic species fail to predict both DGFs and CCN number concentration. In fact, this study shows that a good reproduction of the measured DGF and CCN concentration is obtained if the chemical composition of aerosol, especially that of WSOC, is appropriately taken into account in the calculations. New parameterizations for the computed CCN spectra are also derived which take into account the variability caused by chemical effects (surface tension, molecular composition, solubility, degree of dissociation of WSOC). | |||||
BibTeX:
@article{mircea_importance_2005, author = {Mircea, M. and Facchini, M. C. and Decesari, S. and Cavalli, F. and Emblico, L. and Fuzzi, S. and Vestin, A. and Rissler, J. and Swietlicki, E. and Frank, G. and Andreae, M. O. and Maenhaut, W. and Rudich, Y. and Artaxo, P.}, title = {Importance of the organic aerosol fraction for modeling aerosol hygroscopic growth and activation: a case study in the Amazon Basin}, journal = {Atmospheric Chemistry and Physics}, year = {2005}, volume = {5}, pages = {3111--3126}, url = {://WOS:000233422500001} } |
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Miranda, E.J., Vourlitis, G.L., Priante, N., Priante, P.C., Campelo, J.H., Suli, G.S., Fritzen, C.L., Lobo, F.D.A. and Shiraiwa, S. | Seasonal variation in the leaf gas exchange of tropical forest trees in the rain forest-savanna transition of the southern Amazon Basin | 2005 | Journal of Tropical Ecology Vol. 21, pp. 451-460 |
article | DOI URL |
Abstract: The photosynthetic light response of Amazonian semi-deciduous forest trees of the rain forest-savanna transition near Sinop Mato Grosso. Brazil was measured between July 2000 and September 2003 to test the hypothesis that the photosynthetic capacity of trees acclimated to different growth light environments will decline during the dry season. Maximum photosynthesis (A(max)) and stomatal conductance (g(max)) were significantly higher during the wet season: however, the physiological response to drought was not a clear function of growth light environment. For some species, such as Psycliotria sp. growing in the mid-canopy, internal leaf CO2 concentration (C-i) was textgreater 30%, lower during the dry season suggesting that declines in A(max) were caused in part by stomatal limitations to CO2 diffusion. For other species, such as Brosimum lactescens growing at the top of the canopy, Tovomita schomburgkii growing in the mid-canopy, and Dinizia excelsa growing in the understorey, dry season C-i declined by textless 20%, suggesting that factors independent of CO2 diffusion were more important in limiting A(max). Dry-season declines in g(max) appeared to be important for maintaining a more consistent leaf water potential for some species (T. schomburgkii and D. excelsa) but not others (Psychotria sp.). These results indicate that while seasonal drought exerts an important limitation on the physiological capacity of semi-deciduous Amazonian forest trees, the mechanism of this limitation May differ between species. | |||||
BibTeX:
@article{miranda_seasonal_2005, author = {Miranda, E. J. and Vourlitis, G. L. and Priante, N. and Priante, P. C. and Campelo, J. H. and Suli, G. S. and Fritzen, C. L. and Lobo, F. D. A. and Shiraiwa, S.}, title = {Seasonal variation in the leaf gas exchange of tropical forest trees in the rain forest-savanna transition of the southern Amazon Basin}, journal = {Journal of Tropical Ecology}, year = {2005}, volume = {21}, pages = {451--460}, url = {://WOS:000231009300011}, doi = {https://doi.org/10.1017/s0266467405002427} } |
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Miller, S.D., Goulden, M.L., Menton, M.C., da Rocha, H.R., de Freitas, H.C., Figueira, A. and de Sousa, C.A.D. | Biometric and micrometeorological measurements of tropical forest carbon balance | 2004 | Ecological Applications Vol. 14(4), pp. S114-S126 |
article | URL |
Abstract: We used two independent approaches, biometry and micrometeorology, to determine the net ecosystem production (NEP) of an old growth forest in Para, Brazil. Biometric inventories indicated that the forest was either a source or, at most, a modest sink of carbon from 1984 to 2000 (+0.8 +/- 2 Mg C(.)ha(-1.)yr(-1); a positive flux indicates carbon loss by the forest, a negative flux indicates carbon gain). Eddy covariance measurements of CO2 exchange were made from July 2000 to July 2001 using both open- and closed-path gas analyzers. The annual eddy covariance flux-calculated without correcting for the underestimation of flux on calm nights indicated that the forest was a large carbon sink (-3.9 Mg C.ha(-1.)yr(-1)). This annual uptake is comparable to past reports from other Amazonian forests, which also were calculated without correcting for calm nights. The magnitude of the annual integral was relatively insensitive to the selection of open- versus closed-path gas analyzer, averaging time, detrending, and high-frequency correction. In contrast, the magnitude of the annual integral was highly sensitive to the treatment of calm nights, changing by over 4 Mg C(.)ha(-1.)yr(-1) when a filter was used to replace the net ecosystem exchange (NEE) during nocturnal periods with u* textless 0.2 m/s. Analyses of the relationship between nocturnal NEE and u* confirmed that the annual sum needs to be corrected for the effect of calm nights, which resulted in our best estimate of the annual flux (+0.4 Mg C(.)ha(-1.)yr(-1)). The observed sensitivity of the annual sum to the u* filter is far greater than has been previously reported for temperate and boreal forests. The annual carbon balance determined by eddy covariance is therefore less certain for tropical than temperate forests. Nonetheless, the biometric and micrometeorological measurements in tandem provide strong evidence that the forest was not a strong, persistent carbon sink during the study interval. | |||||
BibTeX:
@article{miller_biometric_2004, author = {Miller, S. D. and Goulden, M. L. and Menton, M. C. and da Rocha, H. R. and de Freitas, H. C. and Figueira, Ames and de Sousa, C. A. D.}, title = {Biometric and micrometeorological measurements of tropical forest carbon balance}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S114--S126}, url = {://WOS:000223269000011} } |
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Miller, S., Goulden, M., Hutyra, L., Keller, M., Saleska, S., Wofsy, S., Figueira, A., da Rocha, H. and Camargo, P. | Reduced impact logging minimally alters tropical rainforest carbon and energy exchange | 2011 | Proceedings of the National Academy of Sciences of the United States of America Vol. 108(48), pp. 19431-19435 |
article | DOI URL |
Abstract: We used eddy covariance and ecological measurements to investigate the effects of reduced impact logging (RIL) on an old-growth Amazonian forest. Logging caused small decreases in gross primary production, leaf production, and latent heat flux, which were roughly proportional to canopy loss, and increases in heterotrophic respiration, tree mortality, and wood production. The net effect of RIL was transient, and treatment effects were barely discernable after only 1 y. RIL appears to provide a strategy for managing tropical forest that minimizes the potential risks to climate associated with large changes in carbon and water exchange. | |||||
BibTeX:
@article{miller_reduced_2011, author = {Miller, S.D. and Goulden, M.L. and Hutyra, L.R. and Keller, M. and Saleska, S.R. and Wofsy, S.C. and Figueira, A.M.S. and da Rocha, H.R. and Camargo, P.B.}, title = {Reduced impact logging minimally alters tropical rainforest carbon and energy exchange}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2011}, volume = {108}, number = {48}, pages = {19431--19435}, url = {://000297463100066}, doi = {https://doi.org/10.1073/pnas.1105068108} } |
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Miller, S.D., Goulden, M.L. and da Rocha, H.R. | The effect of canopy gaps on subcanopy ventilation and scalar fluxes in a tropical forest | 2007 | Agricultural and Forest Meteorology Vol. 142(1), pp. 25-34 |
article | DOI URL |
Abstract: Forest gaps may provide conduits that preferentially vent moist, CO(2)-rich subcanopy air to the atmosphere. We measured the above-canopy fluxes of momentum, sensible heat (H), CO(2), and water vapor (E(t)), and the vertical profiles Of CO(2) and water vapor, from two 67-m meteorological towers in a selectively logged Brazilian rainforest. The logging removed similar to 3.5 trees ha(-1), and increased the incidence of gaps by a factor of 3 over nearby undisturbed forest. One tower was located in an intact patch of forest within the selectively logged area; the other was 400 m upwind in a large gap created by the logging. During daytime the subcanopy air in the intact patch of forest had more CO(2), More water vapor, and was cooler than the air at comparable altitudes in the gap. Meanwhile, the daytime CO(2) flux was less negative (reduced CO(2) uptake) above the gap than above the intact forest, the daytime E, was greater above the gap than the intact forest, and the daytime H was lower above the gap than the intact forest. These patterns cannot be explained fully by the local loss of canopy gas exchange in the gap, but are consistent with the horizontal transport into the gap, and subsequent vertical transport out of the gap, of high-CO(2), humid, cool air from the forest understory. The understory was drier and warmer during daytime after the logging, which would be expected to increase flammability. Further measurement and modeling efforts are needed to better understand the effect of canopy gaps on the local CO(2) and energy exchange, as well as the flux footprint. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{miller_effect_2007, author = {Miller, S. D. and Goulden, M. L. and da Rocha, H. R.}, title = {The effect of canopy gaps on subcanopy ventilation and scalar fluxes in a tropical forest}, journal = {Agricultural and Forest Meteorology}, year = {2007}, volume = {142}, number = {1}, pages = {25--34}, url = {://WOS:000244053800003}, doi = {https://doi.org/10.1016/j.agrformet.2006.10.008} } |
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Miller, J.B., Gatti, L.V., d'Amelio , M.T.S., Crotwell, A.M., Dlugokencky, E.J., Bakwin, P., Artaxo, P. and Tans, P.P. | Airborne measurements indicate large methane emissions from the eastern Amazon basin | 2007 | Geophysical Research Letters Vol. 34(10) |
article | DOI URL |
Abstract: [1] Recent results from laboratory, field and remote sensing measurements suggest the presence of large methane emissions from the Amazon basin. Here we present regionally integrative, direct trace gas observations from two sites that confirm the presence of large fluxes of methane in eastern Amazonia. Air samples collected on aircraft near Santarem (2.9 degrees S, 55.0 degrees W) and Manaus (2.6 degrees S, 60.0 degrees W) in eastern and central Amazonia show large enhancements of CH(4) that are not seen at the NOAA/ESRL background sites in the tropical Atlantic Ocean. From the surface to about four km, enhancements averaging 34 ppb and up to 200 ppb occur throughout the year and we calculate emissions averaging 27 mg CH(4)/m(2)/day from upwind sources. | |||||
BibTeX:
@article{miller_airborne_2007, author = {Miller, J. B. and Gatti, L. V. and d'Amelio, M. T. S. and Crotwell, A. M. and Dlugokencky, E. J. and Bakwin, P. and Artaxo, P. and Tans, P. P.}, title = {Airborne measurements indicate large methane emissions from the eastern Amazon basin}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {10}, url = {://WOS:000246845900001 http://www.agu.org/pubs/crossref/2007/2006GL029213.shtml}, doi = {https://doi.org/10.1029/2006gl029213} } |
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Miles, L., Grainger, A. and Phillips, O. | The impact of global climate change on tropical forest biodiversity in Amazonia | 2004 | Global Ecology and Biogeography Vol. 13(6), pp. 553-565 |
article | DOI URL |
Abstract: Aim To model long-term trends in plant species distributions in response to predicted changes in global climate. Location Amazonia. Methods The impacts of expected global climate change on the potential and realized distributions of a representative sample of 69 individual Angiosperm species in Amazonia were simulated from 1990 to 2095. The climate trend followed the HADCM2GSa1 scenario, which assumes an annual 1% increase of atmospheric CO2 content with effects mitigated by sulphate forcing. Potential distributions of species in one-degree grid cells were modelled using a suitability index and rectilinear envelope based on bioclimate variables. Realized distributions were additionally limited by spatial contiguity with, and proximity to, known record sites. A size-structured population model was simulated for each cell in the realized distributions to allow for lags in response to climate change, but dispersal was not included. Results In the resulting simulations, 43% of all species became non-viable by 2095 because their potential distributions had changed drastically, but there was little change in the realized distributions of most species, owing to delays in population responses. Widely distributed species with high tolerance to environmental variation exhibited the least response to climate change, and species with narrow ranges and short generation times the greatest. Climate changed most in north-east Amazonia while the best remaining conditions for lowland moist forest species were in western Amazonia. Main conclusions To maintain the greatest resilience of Amazonian biodiversity to climate change as modelled by HADCM2GSa1, highest priority should be given to strengthening and extending protected areas in western Amazonia that encompass lowland and montane forests. | |||||
BibTeX:
@article{miles_impact_2004, author = {Miles, L. and Grainger, A. and Phillips, O.}, title = {The impact of global climate change on tropical forest biodiversity in Amazonia}, journal = {Global Ecology and Biogeography}, year = {2004}, volume = {13}, number = {6}, pages = {553--565}, url = {://WOS:000224648000008}, doi = {https://doi.org/10.1111/j.1466-822X.2004.00105.x} } |
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Michiles, A.A. and Gielow, R. | Above-ground thermal energy storage rates, trunk heat fluxes and surface energy balance in a central Amazonian rainforest | 2008 | Agricultural and Forest Meteorology Vol. 148(6-7), pp. 917-930 |
article | DOI URL |
Abstract: The thermal (physical) energy storage rates (ESR) of the above-ground components of a "terra firme" forest site in central Amazonia, Brazil, were determined for a set of typical days during the dry season of 2003 and the wet season of 2004, and their relevance to the surface energy balance was studied. To obtain the ESR for the above-ground part of the biomass (trunks, branches and litter), the temperatures of one trunk of a dominant tree species of the forest site were measured at three height levels and several radial depths. To compute the ESR in the other parts of the above-ground biomass (twigs, leaves and small size components such as palms and lianas) and the ESR atmospheric fraction, the temperature of the air was measured at four different heights inside and above the forest. The air, trunks and other biomass components contributed 35%, 40% and 25% to the total daily ESR of the forest respectively. For the hourly values during the morning, the total ESR was usually observed to be between 30 and 70 W m(-2), but with maxima that can exceed go W m(-2); during rain events minima as low as -200 W m(-2) were observed. During the night and at dawn and dusk, the total ESR may constitute a sizable fraction of the net radiation, on some occasions equaling, or even exceeding it. On a daily basis, values of the total ESR were observed to be between -40% and 5% of the net radiation, depending on the weather conditions during the day. Further, the inclusion of the ESR to compute the surface energy balance improves its closure, mainly during the daylight period and, particularly, during the morning hours; but the best closure occurs for the days in which the daily balance of the total ESR is positive. Finally, simplified expressions are presented for those components of the ESR which do not depend on trunk temperature. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{michiles_above-ground_2008, author = {Michiles, A. A.S. and Gielow, Ralf}, title = {Above-ground thermal energy storage rates, trunk heat fluxes and surface energy balance in a central Amazonian rainforest}, journal = {Agricultural and Forest Meteorology}, year = {2008}, volume = {148}, number = {6-7}, pages = {917--930}, url = {://WOS:000257006200008}, doi = {https://doi.org/10.1016/j.agrformet.2008.01.001} } |
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Michiles, A. and Gielow, R. | Armazenamento térmico acima do solo e balanço de energia em floresta de terra firme na Amazônia central [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 59-62 |
article | |
BibTeX:
@article{michiles_armazenamento_2007, author = {Michiles, A.A.S and Gielow, R.}, title = {Armazenamento térmico acima do solo e balanço de energia em floresta de terra firme na Amazônia central}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {59--62} } |
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Coe, M.T., Brando, P.M., Lefebvre, P., Panday, P. and Macedo, M.N. | The Hydrology and Energy Balance of the Amazon Basin [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 35-53 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_hydrology_2016, author = {Michael T. Coe, Paulo M. Brando, Paul Lefebvre, Prajjwal Panday, Marcia N. Macedo}, title = {The Hydrology and Energy Balance of the Amazon Basin}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {35--53}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Metcalfe, D.B., Williams, M., Aragao, L.E.O.C., da Costa, A.C.L., de Almeida, S.S., Braga, A.P., Goncalves, P.H.L. and Silva Junior, J.d.A. | A method for extracting plant roots from soil which facilitates rapid sample processing without compromising measurement accuracy | 2007 | New Phytologist Vol. 174(3), pp. 697-703 |
article | DOI URL |
Abstract: This study evaluates a novel method for extracting roots from soil samples and applies it to estimate standing crop root mass (+/- confidence intervals) in an eastern Amazon rainforest. Roots were manually extracted from soil cores over a period of 40 min, which was split into 10 min time intervals. The pattern of cumulative extraction over time was used to predict root extraction beyond 40 min. A maximum-likelihood approach was used to calculate confidence intervals. The temporal prediction method added 21-32% to initial estimates of standing crop root mass. According to predictions, complete manual root extraction from 18 samples would have taken c. 239 h, compared with 12 h using the prediction method. Uncertainties (percentage difference between mean, and 10th and 90th percentiles) introduced by the prediction method were small (12-15%), compared with uncertainties caused by spatial variation in root mass (72-191%, for nine samples per plot surveyed). This method provides a way of increasing the number of root samples processed per unit time, without compromising measurement accuracy. | |||||
BibTeX:
@article{metcalfe_method_2007, author = {Metcalfe, D. B. and Williams, M. and Aragao, L. E. O. C. and da Costa, A. C. L. and de Almeida, S. S. and Braga, A. P. and Goncalves, P. H. L. and Silva Junior, J. de Athaydes}, title = {A method for extracting plant roots from soil which facilitates rapid sample processing without compromising measurement accuracy}, journal = {New Phytologist}, year = {2007}, volume = {174}, number = {3}, pages = {697--703}, note = {Edition: 2007/04/24}, url = {://WOS:000245745500024}, doi = {https://doi.org/10.1111/j.1469-8137.2007.02032.x} } |
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Metcalfe, D.B., Meir, P. and Williams, M. | A comparison of methods for converting rhizotron root length measurements into estimates of root mass production per unit ground area | 2007 | Plant and Soil Vol. 301(1-2), pp. 279-288 |
article | DOI URL |
Abstract: Rhizotrons provide valuable information about plant root production, but measurements are usually made in units of root length per unit surface area of observation window surface. These measurement units are not easily comparable to above-ground plant growth. To address this deficiency, several techniques have been developed to convert rhizotron measurement units into root mass production per unit ground area. In this study, four different conversion methods were applied to the same dataset of rhizotron measurements. This data was used to reveal the effect of conversion method upon estimates of the temporal variation in, and annual magnitude of, gross root mass production. Application of four different conversion methods resulted in gross root production estimates ranging between 2.1 and 11.4 t ha(-1) year(-1). Temporal variation in gross root mass production also varied between methods. All current methods for quantifying root production are likely to cause some disturbance and bias. Based upon a comparison of the sources of error present in each conversion method, we assess which methods are likely to produce the most reliable estimates of root biomass production per unit ground area, and propose additional measurements which could further improve accuracy. | |||||
BibTeX:
@article{metcalfe_comparison_2007, author = {Metcalfe, D. B. and Meir, P. and Williams, M.}, title = {A comparison of methods for converting rhizotron root length measurements into estimates of root mass production per unit ground area}, journal = {Plant and Soil}, year = {2007}, volume = {301}, number = {1-2}, pages = {279--288}, url = {://WOS:000252476000023}, doi = {https://doi.org/10.1007/s11104-007-9447-6} } |
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Metcalfe, D.B., Meir, P., Aragao, L.E.O.C., Malhi, Y., da Costa, A.C.L., Braga, A., Goncalves, P.H.L., de Athaydes, J., de Almeida, S.S. and Williams, M. | Factors controlling spatio-temporal variation in carbon dioxide efflux from surface litter, roots, and soil organic matter at four rain forest sites in the eastern Amazon | 2007 | Journal of Geophysical Research-Biogeosciences Vol. 112(G4) |
article | DOI URL |
Abstract: [1] This study explored biotic and abiotic causes for spatio-temporal variation in soil respiration from surface litter, roots, and soil organic matter over one year at four rain forest sites with different vegetation structures and soil types in the eastern Amazon, Brazil. Estimated mean annual soil respiration varied between 13-17 t C ha(-1) yr(-1), which was partitioned into 0-2 t C ha(-1) yr(-1) from litter, 6-9 t C ha(-1) yr(-1) from roots, and 5-6 t C ha(-1) yr(-1) from soil organic matter. Litter contribution showed no clear seasonal change, though experimental precipitation exclusion over a one-hectare area was associated with a ten-fold reduction in litter respiration relative to unmodified sites. The estimated mean contribution of soil organic matter respiration fell from 49% during the wet season to 32% in the dry season, while root respiration contribution increased from 42% in the wet season to 61% during the dry season. Spatial variation in respiration from soil, litter, roots, and soil organic matter was not explained by volumetric soil moisture or temperature. Instead, spatial heterogeneity in litter and root mass accounted for 44% of observed spatial variation in soil respiration (p textless 0.001). In particular, variation in litter respiration per unit mass and root mass accounted for much of the observed variation in respiration from litter and roots, respectively, and hence total soil respiration. This information about patterns of, and underlying controls on, respiration from different soil components should assist attempts to accurately model soil carbon dioxide fluxes over space and time. | |||||
BibTeX:
@article{metcalfe_factors_2007, author = {Metcalfe, D. B. and Meir, P. and Aragao, L. E. O. C. and Malhi, Y. and da Costa, A. C. L. and Braga, A. and Goncalves, P. H. L. and de Athaydes, J. and de Almeida, S. S. and Williams, M.}, title = {Factors controlling spatio-temporal variation in carbon dioxide efflux from surface litter, roots, and soil organic matter at four rain forest sites in the eastern Amazon}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2007}, volume = {112}, number = {G4}, url = {://WOS:000250046500001}, doi = {https://doi.org/10.1029/2007jg000443} } |
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Metcalfe, D.B., Meir, P., Aragao, L.E.O.C., Lobo-do-Vale, R., Galbraith, D., Fisher, R.A., Chaves, M.M., Maroco, J.P., da Costa, A.C.L., de Almeida, S.S., Braga, A.P., Goncalves, P.H.L., de Athaydes, J., da Costa, M., Portela, T.T.B., de Oliveira, A.A.R., Malhi, Y. and Williams, M. | Shifts in plant respiration and carbon use efficiency at a large-scale drought experiment in the eastern Amazon | 2010 | New Phytologist Vol. 187(3), pp. 608-621 |
article | DOI URL |
Abstract: PtextgreaterThe effects of drought on the Amazon rainforest are potentially large but remain poorly understood. Here, carbon (C) cycling after 5 yr of a large-scale through-fall exclusion (TFE) experiment excluding about 50% of incident rainfall from an eastern Amazon rainforest was compared with a nearby control plot. Principal C stocks and fluxes were intensively measured in 2005. Additional minor components were either quantified in later site measurements or derived from the available literature. Total ecosystem respiration (R(eco)) and total plant C expenditure (PCE, the sum of net primary productivity (NPP) and autotrophic respiration (R(auto))), were elevated on the TFE plot relative to the control. The increase in PCE and R(eco) was mainly caused by a rise in R(auto) from foliage and roots. Heterotrophic respiration did not differ substantially between plots. NPP was 2.4 +/- 1.4 t C ha-1 yr-1 lower on the TFE than the control. Ecosystem carbon use efficiency, the proportion of PCE invested in NPP, was lower in the TFE plot (0.24 +/- 0.04) than in the control (0.32 +/- 0.04). Drought caused by the TFE treatment appeared to drive fundamental shifts in ecosystem C cycling with potentially important consequences for long-term forest C storage. | |||||
BibTeX:
@article{metcalfe_shifts_2010, author = {Metcalfe, D. B. and Meir, P. and Aragao, L. E. O. C. and Lobo-do-Vale, R. and Galbraith, D. and Fisher, R. A. and Chaves, M. M. and Maroco, J. P. and da Costa, A. C. L. and de Almeida, S. S. and Braga, A. P. and Goncalves, P. H. L. and de Athaydes, J. and da Costa, M. and Portela, T. T. B. and de Oliveira, A. A. R. and Malhi, Y. and Williams, M.}, title = {Shifts in plant respiration and carbon use efficiency at a large-scale drought experiment in the eastern Amazon}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {608--621}, note = {Edition: 2010/06/18}, url = {://WOS:000280122500009}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03319.x} } |
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Metcalfe, D.B., Meir, P., Aragao, L.E.O.C., da Costa, A.C.L., Braga, A.P., Goncalves, P.H.L., Silva Jr., J.d.A., de Almeida, S.S., Dawson, L.A., Malhi, Y. and Williams, M. | The effects of water availability on root growth and morphology in an Amazon rainforest | 2008 | Plant and Soil Vol. 311(1-2), pp. 189-199 |
article | DOI URL |
Abstract: This study examined how root growth and morphology were affected by variation in soil moisture at four Amazon rainforest sites with contrasting vegetation and soil types. Mean annual site root mass, length and surface area growth ranged between 3-7 t ha(-1), 2-4 km m(-2) and 8-12 m(2) m(-2) respectively. Mean site specific root length and surface area varied between 8-10 km kg(-1) stop and 24-34 m(2) kg(-1). Growth of root mass, length and surface area was lower when soil water was depleted (P textless 0.001) while specific root length and surface area showed the opposite pattern (P textless 0.001). These results indicate that changes in root length and surface area per unit mass, and pulses in root growth to exploit transient periods of high soil water availability may be important means for trees in this ecosystem to increase nutrient and water uptake under seasonal and longer-term drought conditions. | |||||
BibTeX:
@article{metcalfe_effects_2008, author = {Metcalfe, Daniel B. and Meir, Patrick and Aragao, Luiz Eduardo O. C. and da Costa, Antonio C. L. and Braga, Alan P. and Goncalves, Paulo H. L. and Silva, Jr., Joao de Athaydes and de Almeida, Samuel S. and Dawson, Lorna A. and Malhi, Yadvinder and Williams, Mathew}, title = {The effects of water availability on root growth and morphology in an Amazon rainforest}, journal = {Plant and Soil}, year = {2008}, volume = {311}, number = {1-2}, pages = {189--199}, url = {://WOS:000259042800017}, doi = {https://doi.org/10.1007/s11104-008-9670-9} } |
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Metcalfe, D.B., Lobo-do-Vale, R., Chaves, M.M., Maroco, J.P., Aragao, L.E.O.C., Malhi, Y., Da Costa, A.L., Braga, A.P., Goncalves, P.L., De Athaydes, J., Da Costa, M., Almeida, S.S., Campbell, C., Hurry, V., Williams, M. and Meir, P. | Impacts of experimentally imposed drought on leaf respiration and morphology in an Amazon rain forest | 2010 | Functional Ecology Vol. 24(3), pp. 524-533 |
article | DOI URL |
Abstract: Ptextgreater1. The Amazon region may experience increasing moisture limitation over this century. Leaf dark respiration (R) is a key component of the Amazon rain forest carbon (C) cycle, but relatively little is known about its sensitivity to drought. 2. Here, we present measurements of R standardized to 25 degrees C and leaf morphology from different canopy heights over 5 years at a rain forest subject to a large-scale through-fall reduction (TFR) experiment, and nearby, unmodified Control forest, at the Caxiuana reserve in the eastern Amazon. 3. In all five post-treatment measurement campaigns, mean R at 25 degrees C was elevated in the TFR forest compared to the Control forest experiencing normal rainfall. After 5 years of the TFR treatment, R per unit leaf area and mass had increased by 65% and 42%, respectively, relative to pre-treatment means. In contrast, leaf area index (L) in the TFR forest was consistently lower than the Control, falling by 23% compared to the pre-treatment mean, largely because of a decline in specific leaf area (S). 4. The consistent and significant effects of the TFR treatment on R, L and S suggest that severe drought events in the Amazon, of the kind that may occur more frequently in future, could cause a substantial increase in canopy carbon dioxide emissions from this ecosystem to the atmosphere. | |||||
BibTeX:
@article{metcalfe_impacts_2010, author = {Metcalfe, Daniel B. and Lobo-do-Vale, Raquel and Chaves, Manuela M. and Maroco, Joao P. and Aragao, Luiz E. O. C. and Malhi, Yadvinder and Da Costa, Antonio L. and Braga, Alan P. and Goncalves, Paulo L. and De Athaydes, Joao and Da Costa, Mauricio and Almeida, Samuel S. and Campbell, Catherine and Hurry, Vaughan and Williams, Mathew and Meir, Patrick}, title = {Impacts of experimentally imposed drought on leaf respiration and morphology in an Amazon rain forest}, journal = {Functional Ecology}, year = {2010}, volume = {24}, number = {3}, pages = {524--533}, url = {://WOS:000276508000005}, doi = {https://doi.org/10.1111/j.1365-2435.2009.01683.x} } |
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Metcalfe, D.B., Fisher, R.A. and Wardle, D.A. | Plant communities as drivers of soil respiration: pathways, mechanisms, and significance for global change | 2011 | Biogeosciences Vol. 8(8), pp. 2047-2061 |
article | DOI URL |
Abstract: Understanding the impacts of plant community characteristics on soil carbon dioxide efflux (R) is a key prerequisite for accurate prediction of the future carbon (C) balance of terrestrial ecosystems under climate change. However, developing a mechanistic understanding of the determinants of R is complicated by the presence of multiple different sources of respiratory C within soil - such as soil microbes, plant roots and their mycorrhizal symbionts - each with their distinct dynamics and drivers. In this review, we synthesize relevant information from a wide spectrum of sources to evaluate the current state of knowledge about plant community effects on R, examine how this information is incorporated into global climate models, and highlight priorities for future research. Despite often large variation amongst studies and methods, several general trends emerge. Mechanisms whereby plants affect R may be grouped into effects on belowground C allocation, aboveground litter properties and microclimate. Within vegetation types, the amount of C diverted belowground, and hence R, may be controlled mainly by the rate of photosynthetic C uptake, while amongst vegetation types this should be more dependent upon the specific C allocation strategies of the plant life form. We make the case that plant community composition, rather than diversity, is usually the dominant control on R in natural systems. Individual species impacts on R may be largest where the species accounts for most of the biomass in the ecosystem, has very distinct traits to the rest of the community and/or modulates the occurrence of major natural disturbances. We show that climate vegetation models incorporate a number of pathways whereby plants can affect R, but that simplifications regarding allocation schemes and drivers of litter decomposition may limit model accuracy. We also suggest that under a warmer future climate, many plant communities may shift towards dominance by fast growing plants which produce large quantities of nutrient rich litter. Where this community shift occurs, it could drive an increase in R beyond that expected from direct climate impacts on soil microbial activity alone. We identify key gaps in knowledge and recommend them as priorities for future work. These include the patterns of photosynthate partitioning amongst belowground components, ecosystem level effects of individual plant traits, and the importance of trophic interactions and species invasions or extinctions for ecosystem processes. A final, overarching challenge is how to link these observations and drivers across spatio-temporal scales to predict regional or global changes in R over long time periods. A more unified approach to understanding R, which integrates information about plant traits and community dynamics, will be essential for better understanding, simulating and predicting patterns of R across terrestrial ecosystems and its role within the earth-climate system. | |||||
BibTeX:
@article{metcalfe_plant_2011, author = {Metcalfe, D. B. and Fisher, R. A. and Wardle, D. A.}, title = {Plant communities as drivers of soil respiration: pathways, mechanisms, and significance for global change}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {8}, pages = {2047--2061}, url = {://WOS:000294457100003}, doi = {https://doi.org/10.5194/bg-8-2047-2011} } |
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Metcalfe, D., Meir, P., Aragao, L.E.O.C., da Costa, A., Almeida, S., Braga, A., Goncalves, P., Athaydes, J., Malhi, Y. and Williams, M. | Sample sizes for estimating key ecosystem characteristics in a tropical terra firme rainforest | 2008 | Forest Ecology and Management Vol. 255(3-4), pp. 558-566 |
article | DOI URL |
Abstract: This study evaluated the sample sizes necessary to estimate several soil and vegetation characteristics within 10% confidence intervals with 95% probability in three terra firme tropical rainforest sites. Across all three plots, the most spatially heterogeneous variables were measurements of total standing crop root mass, ground surface litter mass, litter fall, root growth and soil respiration which required, on average, 152, 105, 52, 45 and 28 samples, respectively to estimate mean values within 10% confidence intervals with 95% probability. Leaf area index measurements integrated canopy characteristics over a relatively large spatial area and therefore only required five samples, on average, to achieve the same degree of precision. Measurements of soil temperature, moisture, carbon and nitrogen content in the surface 30 cm soil layer displayed the lowest degree of spatial variation: requiring a maximum of seven samples to estimate mean values within 10% confidence intervals with 95% probability. This study, together with a review of data from similar ecosystems, suggests that standing crop root mass, root growth, litter fall and ground surface litter mass are usually acutely under-sampled, which could impede detection and interpretation of patterns and processes in these potentially important ecosystem characteristics. This information may assist researchers to design effective sampling strategies for field experiments, particularly in tropical forests. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{metcalfe_sample_2008, author = {Metcalfe, Daniel and Meir, Patrick and Aragao, Luiz Eduardo O. C. and da Costa, Antonio and Almeida, Samuel and Braga, Alan and Goncalves, Paulo and Athaydes, Joao and Malhi, Yadvinder and Williams, Mathew}, title = {Sample sizes for estimating key ecosystem characteristics in a tropical terra firme rainforest}, journal = {Forest Ecology and Management}, year = {2008}, volume = {255}, number = {3-4}, pages = {558--566}, url = {://WOS:000254072700019}, doi = {https://doi.org/10.1016/j.foreco.2007.09.026} } |
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Metcalf, O.C., Barlow, J., Marsden, S., Gomes de Moura, N., Berenguer, E., Ferreira, J. and Lees, A.C. | Optimizing tropical forest bird surveys using passive acoustic monitoring and high temporal resolution sampling | 2022 | Remote Sensing in Ecology and Conservation Vol. 8(1), pp. 45-56 |
article | DOI URL |
Abstract: Abstract Estimation of avian biodiversity is a cornerstone measure of ecosystem condition. Surveys conducted using autonomous recorders are often more efficient at estimating diversity than traditional point-count surveys. However, there is limited research into the optimal temporal resolution for sampling—the trade-off between the number of samples and sample duration when sampling a survey window with a fixed survey effort—despite autonomous recorders allowing easy repeat sampling compared to traditional survey methods. We assess whether the additional temporal coverage from high temporal resolution (HTR) sampling, consisting of 240 15-s samples spread randomly across a survey window detects higher alpha and gamma diversity than low temporal resolution (LTR) sampling of four 15-min samples at the same locations. We do so using an acoustic dataset collected from 29 locations in a region of very high avian biodiversity—the eastern Brazilian Amazon. We find HTR sampling outperforms LTR sampling in every metric considered, with HTR sampling predicted to detect approximately 50% higher alpha diversity, and 10% higher gamma diversity. This effect is primarily driven by increased coverage of variation in detectability across the morning, with the earliest period containing a distinct community that is often under sampled using LTR sampling. LTR sampling produced almost four times as many false absences for species presence. Additionally, LTR sampling incorrectly found 70 species (34%) at only a single forest type when they were in fact present in multiple forest types, while the use of HTR sampling reduced this to just two species (0.9%). When considering multiple independent detections of species, HTR sampling detected three times more uncommon species than LTR sampling. We conclude that high temporal resolution sampling of passive-acoustic monitoring-based surveys should be considered the primary method for estimating the species richness of bird communities in tropical forests. | |||||
BibTeX:
@article{metcalf_optimizing_2022, author = {Metcalf, Oliver C. and Barlow, Jos and Marsden, Stuart and Gomes de Moura, Nárgila and Berenguer, Erika and Ferreira, Joice and Lees, Alexander C.}, title = {Optimizing tropical forest bird surveys using passive acoustic monitoring and high temporal resolution sampling}, journal = {Remote Sensing in Ecology and Conservation}, year = {2022}, volume = {8}, number = {1}, pages = {45--56}, url = {https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1002/rse2.227}, doi = {https://doi.org/10.1002/rse2.227} } |
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Messina, J.P., Walsh, S.J., Mena, C.F. and Delamater, P.L. | Land tenure and deforestation patterns in the Ecuadorian Amazon: Conflicts in land conservation in frontier settings | 2006 | Applied Geography Vol. 26(2), pp. 113-128 |
article | DOI URL |
Abstract: The Cuyabeno Wildlife Production Reserve (Cuyabeno Reserve). located in the northeastern Ecuadorian Amazon. is a special protected area. Using a satellite image time-series. landscape ecology and evolving boundary definitions. shifts in landscape composition are described that fools on the spatial and temporal dynamics of land use and cover change (LUCC) within the vicinity of the Cuyabeno Reserve. Changes in local land tenancy and the implementation of protection buffers have accelerated the process of fragmentation and exacerbated the conflict between development and protection. Further. variations in management strategies and ownership histories confound LUCC patterns. rates, and trajectories. (c) 2005 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{messina_land_2006, author = {Messina, Joseph P. and Walsh, Stephen J. and Mena, Carlos F. and Delamater, Paul L.}, title = {Land tenure and deforestation patterns in the Ecuadorian Amazon: Conflicts in land conservation in frontier settings}, journal = {Applied Geography}, year = {2006}, volume = {26}, number = {2}, pages = {113--128}, url = {://WOS:000239134800003}, doi = {https://doi.org/10.1016/j.apgeog.2005.11.003} } |
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Messina, J.P. and Walsh, S.J. | Dynamic spatial simulation modeling of the population - environment matrix in the Ecuadorian Amazon | 2005 | Environment and Planning B-Planning & Design Vol. 32(6), pp. 835-856 |
article | DOI URL |
Abstract: This research uses multithematic and spatially explicit data combined from a longitudinal socioeconomic and demographic survey conducted in 1990 and 1999, GIS coverages of resource endowments and geographic accessibility, and a classified Landsat Thematic Mapper (TM) satellite time series. The goal was to combine such data with expert knowledge, a set of analytic results, and dynamic modeling approaches to describe, explain, and explore the causes and consequences of land use and cover change (LUCC) in the northern Oriente region of the Ecuadorian Amazon. First, a cellular automaton (CA) model representing LUCC was developed using a time series of remotely sensed Landsat TM images for a 90 000-ha intensive study area within the region and calibrated using alternative images from the time series. The classified images were linked to spatially referenced biophysical and socioeconomic coverages used as input data, and then combined with 'rules' derived from empirical analyses. Second, the CA model was used in dynamic simulations to explore LUCC as both causes and consequences of (a) road development, (b) agricultural extensification and land abandonment, (c) major shifts in world markets and crop prices, and (d) urban expansion of the central city within the region. Finally, complexity theory was explored within the spatial and temporal dynamics associated with population-environment interactions, particularly, deforestation, urbanization, and subsistence and commercial cultivation of agricultural crops on lands made accessible by petroleum-company-built roads and the corresponding in-migration of spontaneous colonists beginning in the late 1960s. This research contributes to the study of population-environment interactions in a frontier environment, and examines how dynamic and complex systems can be modeled using CA-based spatial simulations. | |||||
BibTeX:
@article{messina_dynamic_2005, author = {Messina, J. P. and Walsh, S. J.}, title = {Dynamic spatial simulation modeling of the population - environment matrix in the Ecuadorian Amazon}, journal = {Environment and Planning B-Planning & Design}, year = {2005}, volume = {32}, number = {6}, pages = {835--856}, url = {://WOS:000234215700004}, doi = {https://doi.org/10.1068/b31186} } |
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Messina, J.P. and Walsh, S.J. | 2.5D Morphogenesis: modeling landuse and landcover dynamics in the Ecuadorian Amazon | 2001 | Plant Ecology Vol. 156(1), pp. 75-88 |
article | DOI URL |
Abstract: The Ecuadorian Amazon, lying in the headwaters of the Napo and Aguarico River valleys, is experiencing rapid change in Land Use and Land Cover (LULC) conditions and regional landscape diversity uniquely tied to the spontaneous agricultural colonization of the Oriente region of northeastern Ecuador beginning in the mid to late 1970s. Spontaneous colonization occurred on squattered lands located adjacent to oil company roads and in government development sectors composed of multiple 50 ha land parcels organized into `piano key' shaped family farms or fincas. Portions of these fincas were deforested for agricultural extensification depending upon the age of the finca and several site and situation factors. Because fincas are managed at the household level as spatially discrete, temporally independent units, land conversion at the finca-level is recognized as the chief proximate cause of deforestation within the region. Focusing on the spatial and temporal dynamics of deforestation, agricultural extensification, and plant succession at the finca-level, and urbanization at the community-level, a cell-based morphogenetic model of Land Use and Land Cover Change (LULCC) was developed as the foundation for a predictive model of regional LULCC dynamics and landscape diversity. Here, LULC characteristics are determined using a time-series of remotely sensed data (i.e., Landsat Thematic Mapper (TM) and Multispectral Scanner (MSS)) using an experimental [semi-traditional] (hybrid unsupervised-supervised) classification scheme resulting in a time-series data set including LULC images for 1973, 1986, 1989, 1996, and 1999. Pixel histories of LULC type across the time-series were integrated into LULC trajectories and converted into seed or input data sets for LULC modeling to alternate time periods and for model validation. LULC simulations, achieved through cellular automata (CA) methodologies, were run on an annual basis to the year 2010 using 1973 as the initial conditions and the satellite time-series as the `check points' in the simulations. The model was developed using the Imagine Spatial Modeler of the ERDAS image processing software, and enhanced using the Spatial Modeler Language (SML). The model works by (a) simulating the present by extrapolating from the past using the image time-series, (b) validating the simulations via the remotely sensed time-series of past conditions and through field observations of current conditions, (c) allowing the model to iterate to the year 2010, and (d) comparing model outputs to an autoregressive time-series approach for annual conditions that are compared via paired t-tests of pattern metrics run at the landscape-level to define compositional and structural differences between successive model outputs. | |||||
BibTeX:
@article{messina_25d_2001, author = {Messina, J. P. and Walsh, S. J.}, title = {2.5D Morphogenesis: modeling landuse and landcover dynamics in the Ecuadorian Amazon}, journal = {Plant Ecology}, year = {2001}, volume = {156}, number = {1}, pages = {75--88}, url = {://WOS:000171300500005 http://www.springerlink.com/content/v486384330mu7l08/fulltext.pdf}, doi = {https://doi.org/10.1023/a:1011901023485} } |
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Mesquita, R.D.G. | Management of advanced regeneration in secondary forests of the Brazilian Amazon | 2000 | Forest Ecology and Management Vol. 130(1-3), pp. 131-140 |
article | URL |
Abstract: Gap formation is a critical process for plant establishment that may be absent or infrequent in second-growth forests, negatively influencing their ability to become diverse mature forest. I simulated treefall gaps within a 10-year-old secondary forest established on a clear-cut area, because cut areas may have a greater potential for economic exploitation than areas used for pastures and shifting cultivation. I explored the effects of varying degrees of canopy opening on the growth of plants already established as advanced regeneration. Five intensities of canopy opening were created: total removal (100%), 80-90%, 50-60%, 20-30% and a 0% control. Only trees textgreater5 cm DBH were cut. The established plant community was diverse, and comprised 37 families and 126 species and morpho-species, of which 72% had some use reported in the literature. I found that the canopy opening treatments resulted in very little disturbance to the established seedling and sapling community, with no significant increase in mortality, but had a strong positive effect on their growth. Light levels reaching the understory were increased from 1% of incident photosynthetic active radiation in control plots to 35% in 100% canopy opening plots. During the first year, differences in plant growth were not significant, but by the second year, differential plant growth associated with canopy opening became evident. Most seedlings (51%) grew approximately 25 cm in height, and approximately one quarter grew more than 25 cm. Only 2.6% of the seedlings decreased in height, and 12% did not grow at all. Fifty percent canopy removal resulted in an almost threefold increase in plant height compared to control plots (0.52 +/- 0.4 m and 0.20 +/- 0.2 m, respectively), and was not significantly different from 80 or 100% removal. This indicates that intermediate levels of canopy removal had positive effects and total removal was unnecessary to stimulate the best growth responses. I conclude that regeneration of diverse mature forest can be accelerated under some conditions by partial removal of secondary forest canopy. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{mesquita_management_2000, author = {Mesquita, R. D. G.}, title = {Management of advanced regeneration in secondary forests of the Brazilian Amazon}, journal = {Forest Ecology and Management}, year = {2000}, volume = {130}, number = {1-3}, pages = {131--140}, url = {://WOS:000086534100012} } |
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Mesquita, R.C.G., Ickes, K., Ganade, G. and Williamson, G.B. | Alternative successional pathways in the Amazon Basin | 2001 | Journal of Ecology Vol. 89(4), pp. 528-537 |
article | DOI URL |
Abstract: 1 Successional pathways were evaluated in two Amazonian secondary forest communities with different land-use histories. Sites which had been clearcut without subsequent use were dominated after 6-10 years by the pioneer genus Cecropia (Moraceae), whereas those used for pasture before abandonment were dominated by the pioneer genus Vismia (Clusiaceae). 2 There were 58 plant families and 300 species identified in Cecropia stands but only 43 families and 147 species were identified in Vismia stands. There were 77 species in common (Sorensen similarity = 0.34). 3 Differences in species number and composition of recruiting individuals between stand types were significant and were a function of the dominant pioneer genus, stem density, distance from primary forest, and land-use history. Regeneration under Vismia canopy was dominated by small Vismia individuals (25% of plants textless 2 cm basal diameter), whereas regeneration under Cecropia canopy was more diverse and did not include a single young Cecropia. 4 The number of regenerating plants in both secondary stand types dropped off sharply with distance (5, 25, 50, and 100 m) from primary forest, suggesting that seed dispersal was limiting plant recruitment. Species richness also declined with distance and could be explained by the decline in plant density. Species richness in Cecropia stands increased linearly with plant density, but in Vismia stands the richness increase with density was a decelerating function. 5 For the central Amazon, secondary succession involves a more rapid return of primary forest species if deforestation is not followed by use as pasture before abandonment. | |||||
BibTeX:
@article{mesquita_alternative_2001, author = {Mesquita, R. C. G. and Ickes, K. and Ganade, G. and Williamson, G. B.}, title = {Alternative successional pathways in the Amazon Basin}, journal = {Journal of Ecology}, year = {2001}, volume = {89}, number = {4}, pages = {528--537}, url = {://WOS:000170666800003 http://onlinelibrary.wiley.com/store/10.1046/j.1365-2745.2001.00583.x/asset/j.1365-2745.2001.00583.x.pdf?v=1&t=h6hwhv9t&s=c61783e6c4887e986baf761ec7049a051f791410}, doi = {https://doi.org/10.1046/j.1365-2745.2001.00583.x} } |
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Mesquita, R.C.G., Delamonica, P. and Laurance, W.F. | Effect of surrounding vegetation on edge-related tree mortality in Amazonian forest fragments | 1999 | Biological Conservation Vol. 91(2-3), pp. 129-134 |
article | DOI URL |
Abstract: Little is known about factors that cause spatial variability in edge effects, the diverse physical and biotic changes associated with the abrupt boundaries of fragmented forests. We examined the influence of three types of surrounding vegetation (cattle pastures. Cecropia-dominated regrowth, and Vismia-dominated regrowth). on edge-related tree mortality in Amazonian rainforest fragments. An ANCOVA revealed that the type of surrounding vegetation and distance to edge both had significant effects on tree mortality. Differences among vegetation types were greatest within 0-20 m of fragment edges; with edges bordered by cattle pastures having higher mortality than those bordered by Cecropia- and Vismia-dominated regrowth. Edge effects appeared to penetrate further into pasture-bordered edges (ca. 60-100 m) than those bordered by regrowth forest (ca. 40-60 m), but this difference was nonsignificant because of considerable patchiness in tree mortality. Overall, our results suggest that edge effects in forest fragments are significantly influenced by the structure of surrounding vegetation, and that the capacity of different regrowth forests to buffer edge effects can be predicted from the growth form and stand features of the dominant tree species. Management of surrounding vegetation can ameliorate the negative effects of edge creation on small forest fragments. (C) 1999 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{mesquita_effect_1999, author = {Mesquita, R. C. G. and Delamonica, P. and Laurance, W. F.}, title = {Effect of surrounding vegetation on edge-related tree mortality in Amazonian forest fragments}, journal = {Biological Conservation}, year = {1999}, volume = {91}, number = {2-3}, pages = {129--134}, url = {://WOS:000083531100005}, doi = {https://doi.org/10.1016/s0006-3207(99)00086-5} } |
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Merry, F.D., Amacher, G.S., Lima, E. and Nepstad, D.C. | A risky forest policy in the Amazon? [BibTeX] |
2003 | Science Vol. 299(5614), pp. 1843-1843 |
article | DOI URL |
BibTeX:
@article{merry_risky_2003, author = {Merry, F. D. and Amacher, G. S. and Lima, E. and Nepstad, D. C.}, title = {A risky forest policy in the Amazon?}, journal = {Science}, year = {2003}, volume = {299}, number = {5614}, pages = {1843--1843}, note = {Edition: 2003/03/22}, url = {://WOS:000181669700017}, doi = {https://doi.org/10.1126/science.299.5614.1843b} } |
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Merry, F., Soares-Filho, B., Nepstad, D., Amacher, G. and Rodrigues, H. | Balancing Conservation and Economic Sustainability: The Future of the Amazon Timber Industry | 2009 | Environmental Management Vol. 44(3), pp. 395-407 |
article | DOI URL |
Abstract: Logging has been a much maligned feature of frontier development in the Amazon. Most discussions ignore the fact that logging can be part of a renewable, environmentally benign, and broadly equitable economic activity in these remote places. We estimate there to be some 4.5 +/- A 1.35 billion m(3) of commercial timber volume in the Brazilian Amazon today, of which 1.2 billion m(3) is currently profitable to harvest, with a total potential stumpage value of $15.4 billion. A successful forest sector in the Brazilian Amazon will integrate timber harvesting on private lands and on unprotected and unsettled government lands with timber concessions on public lands. If a legal, productive, timber industry can be established outside of protected areas, it will deliver environmental benefits in synergy with those provided by the region's network of protected areas, the latter of which we estimate to have an opportunity cost from lost timber revenues of $2.3 billion over 30 years. Indeed, on all land accessible to harvesting, the timber industry could produce an average of more than 16 million m(3) per year over a 30-year harvest cycle-entirely outside of current protected areas-providing $4.8 billion in returns to landowners and generating $1.8 billion in sawnwood sales tax revenue. This level of harvest could be profitably complemented with an additional 10% from logging concessions on National Forests. This advance, however, should be realized only through widespread adoption of reduced impact logging techniques. | |||||
BibTeX:
@article{merry_balancing_2009, author = {Merry, Frank and Soares-Filho, Britaldo and Nepstad, Daniel and Amacher, Gregory and Rodrigues, Hermann}, title = {Balancing Conservation and Economic Sustainability: The Future of the Amazon Timber Industry}, journal = {Environmental Management}, year = {2009}, volume = {44}, number = {3}, pages = {395--407}, note = {Edition: 2009/07/29}, url = {://WOS:000268901300001 http://www.springerlink.com/content/e6w37111k77uh756/fulltext.pdf}, doi = {https://doi.org/10.1007/s00267-009-9337-1} } |
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Merry, F., Amacher, G. and Lima, E. | Land Values in Frontier Settlements of the Brazilian Amazon | 2008 | World Development Vol. 36(11), pp. 2390-2401 |
article | DOI URL |
Abstract: Even in the absence of formal land markets, estimated values on agricultural frontiers of the Brazilian Amazon reflect the value-adding characteristics of the land. Understanding these characteristics provides important insights to the incentives (or dis-incentives) to protect tropical forests and reduce deforestation. A hedonic model is used to identify characteristics determining smallholder land values on the Amazon frontier. Years on the lot, area under agricultural production, and house values were found to add value; while distance from the nearest city and area under forest decreased values. Characteristics that do not appear to significantly affect land value include pasture area and the claim to hold definitive title. By not adding significantly to land values, pasture may be used to establish property rights rather than to increase land value through positive rents. Our results also confirm the underutilization of the forest resource by smallholders. (C) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{merry_land_2008, author = {Merry, Frank and Amacher, Gregory and Lima, Eirivelthon}, title = {Land Values in Frontier Settlements of the Brazilian Amazon}, journal = {World Development}, year = {2008}, volume = {36}, number = {11}, pages = {2390--2401}, url = {://WOS:000261117100017}, doi = {https://doi.org/10.1016/j.worlddev.2007.11.014} } |
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Mercado, L., Sandra Patino, S., Domingues, T., Fyllas, N., Weedon, G., Sitch, S., Quesada, C., Phillips, O., Aragao, L., Malhi, Y., Dolman, A., Restrepo-Coupe, N., Saleska, S., Baker, T., Almeida, S., Higuchi, N. and Lloyd, J. | Variations in Amazon forest productivity correlated with foliar nutrients and modelled rates of photosynthetic carbon supply | 2011 | Philosophical Transactions of the Royal Society B: Biological Sciences Vol. 366(1582), pp. 3316-3329 |
article | DOI URL |
Abstract: The rate of above-ground woody biomass production, W(P), in some western Amazon forests exceeds those in the east by a factor of 2 or more. Underlying causes may include climate, soil nutrient limitations and species composition. In this modelling paper, we explore the implications of allowing key nutrients such as N and P to constrain the photosynthesis of Amazon forests, and also we examine the relationship between modelled rates of photosynthesis and the observed gradients in W(P). We use a model with current understanding of the underpinning biochemical processes as affected by nutrient availability to assess: (i) the degree to which observed spatial variations in foliar [N] and [P] across Amazonia affect stand-level photosynthesis; and (ii) how these variations in forest photosynthetic carbon acquisition relate to the observed geographical patterns of stem growth across the Amazon Basin. We find nutrient availability to exert a strong effect on photosynthetic carbon gain across the Basin and to be a likely important contributor to the observed gradient in W(P). Phosphorus emerges as more important than nitrogen in accounting for the observed variations in productivity. Implications of these findings are discussed in the context of future tropical forests under a changing climate. | |||||
BibTeX:
@article{mercado_variations_2011, author = {Mercado, L.M. and Sandra Patino, S. and Domingues, T.F. and Fyllas, N.M. and Weedon, G.P. and Sitch, S. and Quesada, C.A. and Phillips, O.L. and Aragao, L.E.O.C. and Malhi, Y. and Dolman, A.J. and Restrepo-Coupe, N. and Saleska, S.R. and Baker, T.R. and Almeida, S. and Higuchi, N. and Lloyd, J.}, title = {Variations in Amazon forest productivity correlated with foliar nutrients and modelled rates of photosynthetic carbon supply}, journal = {Philosophical Transactions of the Royal Society B: Biological Sciences}, year = {2011}, volume = {366}, number = {1582}, pages = {3316--3329}, note = {Edition: 2011/10/19}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22006971}, doi = {https://doi.org/10.1098/rstb.2011.0045} } |
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Mercado, L.M., Lloyd, J., Dolman, A.J., Sitch, S. and Patino, S. | Modelling basin-wide variations in Amazon forest productivity - Part 1: Model calibration, evaluation and upscaling functions for canopy photosynthesis (vol 6, pg 1247, 2009) [BibTeX] |
2011 | Biogeosciences Vol. 8(3), pp. 653-656 |
article | DOI URL |
BibTeX:
@article{mercado_modelling_2011, author = {Mercado, L. M. and Lloyd, J. and Dolman, A. J. and Sitch, S. and Patino, S.}, title = {Modelling basin-wide variations in Amazon forest productivity - Part 1: Model calibration, evaluation and upscaling functions for canopy photosynthesis (vol 6, pg 1247, 2009)}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {3}, pages = {653--656}, url = {://000288911300008}, doi = {https://doi.org/10.5194/bg-8-653-2011} } |
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Mercado, L.M., Lloyd, J., Dolman, A.J., Sitch, S. and Patino, S. | Modelling basin-wide variations in Amazon forest productivity - Part 1: Model calibration, evaluation and upscaling functions for canopy photosynthesis | 2009 | Biogeosciences Vol. 6(7), pp. 1247-1272 |
article | DOI URL |
Abstract: Given the importance of Amazon rainforest in the global carbon and hydrological cycles, there is a need to parameterize and validate ecosystem gas exchange and vegetation models for this region in order to adequately simulate present and future carbon and water balances. In this study, a sun and shade canopy gas exchange model is calibrated and evaluated at five rainforest sites using eddy correlation measurements of carbon and energy fluxes. textless/br textgreater textless/br textgreater Results from the model-data evaluation suggest that with adequate parameterisation, photosynthesis models taking into account the separation of diffuse and direct irradiance and the dynamics of sunlit and shaded leaves can accurately represent photosynthesis in these forests. Also, stomatal conductance formulations that only take into account atmospheric demand fail to correctly simulate moisture and CO(2) fluxes in forests with a pronounced dry season, particularly during afternoon conditions. Nevertheless, it is also the case that large uncertainties are associated not only with the eddy correlation data, but also with the estimates of ecosystem respiration required for model validation. To accurately simulate Gross Primary Productivity (GPP) and energy partitioning the most critical parameters and model processes are the quantum yield of photosynthetic uptake, the maximum carboxylation capacity of Rubisco, and simulation of stomatal conductance. textless/br textgreater textless/br textgreater Using this model-data synergy, we developed scaling functions to provide estimates of canopy photosynthetic parameters for a range of diverse forests across the Amazon region, utilising the best fitted parameter for maximum carboxylation capacity of Rubisco, and foliar nutrients (N and P) for all sites. | |||||
BibTeX:
@article{mercado_modelling_2009, author = {Mercado, L. M. and Lloyd, J. and Dolman, A. J. and Sitch, S. and Patino, S.}, title = {Modelling basin-wide variations in Amazon forest productivity - Part 1: Model calibration, evaluation and upscaling functions for canopy photosynthesis}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {7}, pages = {1247--1272}, url = {://WOS:000268623200008}, doi = {https://doi.org/10.5194/bg-6-1247-2009} } |
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Mercado, L., Huntingford, C., Gash, J., Cox, P. and Jogireddy, V. | Improving the representation of radiation interception and photosynthesis for climate model applications | 2007 | Tellus Vol. 59B(3), pp. 553-565 |
article | DOI URL |
Abstract: The Joint UKL and Environment Simulator (JULES) (which is based on Met Office Surface Exchange Scheme MOSES), the land surface scheme of the Hadley Centre General Circulation Models (GCM) has been improved to contain an explicit description of light interception for different canopy levels, which consequently leads to a multilayer approach to scaling from leaf to canopy level photosynthesis. We test the improved JULES model at a site in the Amazonian rainforest by comparing against measurements of vertical profiles of radiation through the canopy, eddy covariance measurements of carbon and energy fluxes, and also measurements of carbon isotopic fractionation from top canopy leaves. Overall, the new light interception formulation improves modelled photosynthetic carbon uptake compared to the standard big leaf approach used in the original JULES formulation. Additional model improvement was not significant when incorporating more realistic vertical variation of photosynthetic capacity. Even with the improved representation of radiation interception, JULES simulations of net carbon uptake underestimate eddy covariance measurements by 14%. This discrepancy can be removed by either increasing the photosynthetic capacity throughout the canopy or by explicitly including light inhibition of leaf respiration. Along with published evidence of such inhibition of leaf respiration, our study suggests this effect should be considered for inclusion in other GCMs. |
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BibTeX:
@article{mercado_improving_2007, author = {Mercado, L.M. and Huntingford, C. and Gash, J.H.C. and Cox, P.M. and Jogireddy, V.}, title = {Improving the representation of radiation interception and photosynthesis for climate model applications}, journal = {Tellus}, year = {2007}, volume = {59B}, number = {3}, pages = {553--565}, url = {://000247174300023}, doi = {https://doi.org/10.1111/j.1600-0889.2007.00256.x} } |
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Mercado, L., Carswell, J., Malhi, F., Meir, Y., Nobre, P. and L., A.D. | Modelling Amazonian forest eddy covariance data: a comparison of big leaf versus sun/shade models for the C-14 tower at Manaus I. Canopy photosynthesis [BibTeX] |
2006 | Acta Amazonica Vol. 36, pp. 69-82 |
article | |
BibTeX:
@article{mercado_modelling_2006, author = {Mercado, Lloyd, J., Carswell, F., Malhi, Y., Meir, P., Nobre, A.D., L.}, title = {Modelling Amazonian forest eddy covariance data: a comparison of big leaf versus sun/shade models for the C-14 tower at Manaus I. Canopy photosynthesis}, journal = {Acta Amazonica}, year = {2006}, volume = {36}, pages = {69--82} } |
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Meninéa-Neto, E., Martins, H., Dias-Júnior, C., Santana, R., V Brondani, D., Manzi, A., de Araújo, A., Teixeira, P.R., Sörgel, M. and Mortarini, L. | Simulation of the Scalar Transport above and within the Amazon Forest Canopy [BibTeX] |
12 | Atmosphere Vol. 12, pp. 1 |
article | DOI |
BibTeX:
@article{meninea-neto_simulation_12, author = {Meninéa-Neto, Edivaldo and Martins, Hardiney and Dias-Júnior, Cléo and Santana, Raoni and V Brondani, Daiane and Manzi, Antonio and de Araújo, Alessandro and Teixeira, Paulo Ricardo and Sörgel, M. and Mortarini, Luca}, title = {Simulation of the Scalar Transport above and within the Amazon Forest Canopy}, journal = {Atmosphere}, year = {12}, volume = {12}, pages = {1}, doi = {https://doi.org/10.3390/atmos12121631} } |
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Meng, L., Chambers, J., Koven, C., Pastorello, G., Gimenez, B., Jardine, K., Tang, Y., McDowell, N., Negron-Juarez, R., Longo, M., Araujo, A., Tomasella, J., Fontes, C., Mohan, M. and Higuchi, N. | Soil moisture thresholds explain a shift from light-limited to water-limited sap velocity in the Central Amazon during the 2015–16 El Niño drought | 2022 | Environmental Research Letters Vol. 17(6), pp. 064023 |
article | DOI URL |
Abstract: Transpiration is often considered to be light- but not water-limited in humid tropical rainforests due to abundant soil water, even during the dry seasons. The record-breaking 2015–16 El Niño drought provided a unique opportunity to examine whether transpiration is constrained by water under severe lack of rainfall. We measured sap velocity, soil water content, and meteorological variables in an old-growth upland forest in the Central Amazon throughout the 2015–16 drought. We found a rapid decline in sap velocity (−38 ± 21%, mean ± SD.) and in its temporal variability (−88%) during the drought compared to the wet season. Such changes were accompanied by a marked decline in soil moisture and an increase in temperature and vapor pressure deficit. Sap velocity was largely limited by net radiation during the wet and normal dry seasons; however, it shifted to be primarily limited by soil moisture during the drought. The threshold in which sap velocity became dominated by soil moisture was at 0.33 m3 m−3 (around −150 kPa in soil matric potential), below which sap velocity dropped steeply. Our study provides evidence for a soil water threshold on transpiration in a moist tropical forest, suggesting a shift from light limitation to water limitation under future climate characterized by increased temperature and an increased frequency, intensity, duration and extent of extreme drought events. | |||||
BibTeX:
@article{meng_soil_2022, author = {Meng, Lin and Chambers, Jeffrey and Koven, Charles and Pastorello, Gilberto and Gimenez, Bruno and Jardine, Kolby and Tang, Yao and McDowell, Nate and Negron-Juarez, Robinson and Longo, Marcos and Araujo, Alessandro and Tomasella, Javier and Fontes, Clarissa and Mohan, Midhun and Higuchi, Niro}, title = {Soil moisture thresholds explain a shift from light-limited to water-limited sap velocity in the Central Amazon during the 2015–16 El Niño drought}, journal = {Environmental Research Letters}, year = {2022}, volume = {17}, number = {6}, pages = {064023}, url = {http://dx.doi.org/10.1088/1748-9326/ac6f6d}, doi = {https://doi.org/10.1088/1748-9326/ac6f6d} } |
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Menezes, J., Garcia, S., Grandis, A., Nascimento, H., Domingues, T.F., Guedes, A.V., Aleixo, I., Camargo, P., Campos, J., Damasceno, A., Dias-Silva, R., Fleischer, K., Kruijt, B., Cordeiro, A.L., Martins, N.P., Meir, P., Norby, R.J., Pereira, I., Portela, B., Rammig, A., Ribeiro, A.G., Lapola, D.M. and Quesada, C.A. | Changes in leaf functional traits with leaf age: when do leaves decrease their photosynthetic capacity in Amazonian trees? | 2021 | Tree Physiology | article | DOI URL |
Abstract: Most leaf functional trait studies in the Amazon basin do not consider ontogenetic variations (leaf age), which may influence ecosystem productivity throughout the year. When leaf age is taken into account, it is generally considered discontinuous, and leaves are classified into age categories based on qualitative observations. Here, we quantified age-dependent changes in leaf functional traits such as the maximum carboxylation rate of ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco) (Vcmax), stomatal control (Cgs%), leaf dry mass per area and leaf macronutrient concentrations for nine naturally growing Amazon tropical trees with variable phenological strategies. Leaf ages were assessed by monthly censuses of branch-level leaf demography; we also performed leaf trait measurements accounting for leaf chronological age based on days elapsed since the first inclusion in the leaf demography, not predetermined age classes. At the tree community scale, a nonlinear relationship between Vcmax and leaf age existed: young, developing leaves showed the lowest mean photosynthetic capacity, increasing to a maximum at 45 days and then decreasing gradually with age in both continuous and categorical age group analyses. Maturation times among species and phenological habits differed substantially, from 8 ± 30 to 238 ± 30 days, and the rate of decline of Vcmax varied from −0.003 to −0.065 μmol CO2 m−2 s−1 day−1. Stomatal control increased significantly in young leaves but remained constant after peaking. Mass-based phosphorus and potassium concentrations displayed negative relationships with leaf age, whereas nitrogen did not vary temporally. Differences in life strategies, leaf nutrient concentrations and phenological types, not the leaf age effect alone, may thus be important factors for understanding observed photosynthesis seasonality in Amazonian forests. Furthermore, assigning leaf age categories in diverse tree communities may not be the recommended method for studying carbon uptake seasonality in the Amazon, since the relationship between Vcmax and leaf age could not be confirmed for all trees. | |||||
BibTeX:
@article{menezes_changes_2021, author = {Menezes, Juliane and Garcia, Sabrina and Grandis, Adriana and Nascimento, Henrique and Domingues, Tomas F and Guedes, Alacimar V and Aleixo, Izabela and Camargo, Plínio and Campos, Jéssica and Damasceno, Amanda and Dias-Silva, Renann and Fleischer, Katrin and Kruijt, Bart and Cordeiro, Amanda L and Martins, Nathielly P and Meir, Patrick and Norby, Richard J and Pereira, Iokanam and Portela, Bruno and Rammig, Anja and Ribeiro, Ana Gracy and Lapola, David M and Quesada, Carlos A}, title = {Changes in leaf functional traits with leaf age: when do leaves decrease their photosynthetic capacity in Amazonian trees?}, journal = {Tree Physiology}, year = {2021}, url = {https://doi.org/10.1093/treephys/tpab042}, doi = {https://doi.org/10.1093/treephys/tpab042} } |
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Mendonca, M.J.C., Diaz, M.D.V., Nepstad, D., da Motta, R.S., Alencar, A., Gomes, J.C. and Ortiz, R.A. | The economic cost of the use of fire in the Amazon | 2004 | Ecological Economics Vol. 49(1), pp. 89-105 |
article | DOI URL |
Abstract: The objective of this study is to investigate the cost of the use of fire in the Amazon. Burnings are commonplace in the Amazon production process and contribute towards the region's agricultural expansion. Fire is used by farmers in the land preparation process and in clearing forest areas. It also helps combat plants that overrun pastures. However, fire also generates losses for farmers and landowners when it gets out of control. Since the use of fire from a private perspective obeys an economic rationale, the measurement of losses associated to the use of fire must consider the difference between intentional and accidental fires. This study introduces these important concepts which are fundamental to measure the cost of fire. Losses also reach social proportions. To address this issue, we estimated losses related to the release of carbon into the atmosphere, as well as losses due to respiratory ailments provoked by smoke from fires. Our study covered costs related to accidental pasture fires, fence losses, forest losses, carbon emissions, and impacts on human health. Our most conservative estimates indicate an average cost of around 0.2% of the region's GDP during the 1996-1999 period. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{mendonca_economic_2004, author = {Mendonca, M. J. C. and Diaz, M. D. V. and Nepstad, D. and da Motta, R. S. and Alencar, A. and Gomes, J. C. and Ortiz, R. A.}, title = {The economic cost of the use of fire in the Amazon}, journal = {Ecological Economics}, year = {2004}, volume = {49}, number = {1}, pages = {89--105}, url = {://WOS:000222137100007}, doi = {https://doi.org/10.1016/j.ecolecon.2003.11.011} } |
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Mendes, D. and Marengo, J.A. | Temporal downscaling: a comparison between artificial neural network and autocorrelation techniques over the Amazon Basin in present and future climate change scenarios | 2010 | Theoretical and Applied Climatology Vol. 100(3-4), pp. 413-421 |
article | DOI URL |
Abstract: Several studies have been devoted to dynamic and statistical downscaling for both climate variability and climate change. This paper introduces an application of temporal neural networks for downscaling global climate model output and autocorrelation functions. This method is proposed for downscaling daily precipitation time series for a region in the Amazon Basin. The downscaling models were developed and validated using IPCC AR4 model output and observed daily precipitation. In this paper, five AOGCMs for the twentieth century (20C3M; 1970-1999) and three SRES scenarios (A2, A1B, and B1) were used. The performance in downscaling of the temporal neural network was compared to that of an autocorrelation statistical downscaling model with emphasis on its ability to reproduce the observed climate variability and tendency for the period 1970-1999. The model test results indicate that the neural network model significantly outperforms the statistical models for the downscaling of daily precipitation variability. | |||||
BibTeX:
@article{mendes_temporal_2010, author = {Mendes, David and Marengo, Jose A.}, title = {Temporal downscaling: a comparison between artificial neural network and autocorrelation techniques over the Amazon Basin in present and future climate change scenarios}, journal = {Theoretical and Applied Climatology}, year = {2010}, volume = {100}, number = {3-4}, pages = {413--421}, url = {://WOS:000277098800013}, doi = {https://doi.org/10.1007/s00704-009-0193-y} } |
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Mencuccini, M., Minunno, F., Salmon, Y., Martinez-Vilalta, J. and Holtta, T. | Coordination of physiological traits involved in drought-induced mortality [BibTeX] |
2015 | New Phytologist Vol. 208, pp. 396-409 |
article | |
BibTeX:
@article{mencuccini_coordination_2015, author = {Mencuccini, M. and Minunno, F. and Salmon, Y. and Martinez-Vilalta, J. and Holtta, T.}, title = {Coordination of physiological traits involved in drought-induced mortality}, journal = {New Phytologist}, year = {2015}, volume = {208}, pages = {396--409} } |
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Mena-Garcia, R., Justino, G., Araújo, V., Souza, L., Camargo, L. and Gonçalves, J. | Mineral Nitrogen Associated Changes in Growth and Xylem-N Compounds in Amazonian Legume Tree [BibTeX] |
2015 | Journal of Plant Nutrition Vol. 38, pp. 584-595 |
article | |
BibTeX:
@article{mena-garcia_mineral_2015, author = {Mena-Garcia, R.P. and Justino, G.C. and Araújo, V.B.F. and Souza, L.A.G. and Camargo, L.S. and Gonçalves, J.F.C.}, title = {Mineral Nitrogen Associated Changes in Growth and Xylem-N Compounds in Amazonian Legume Tree}, journal = {Journal of Plant Nutrition}, year = {2015}, volume = {38}, pages = {584--595} } |
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Mena, C.F., Walsh, S.J., Frizzelle, B.G., Yao, X. and Malanson, G.P. | Land use change on household farms in the Ecuadorian Amazon Design and implementation of an agent-based model | 2011 | Applied Geography Vol. 31(1), pp. 210-222 |
article | DOI URL |
Abstract: This paper describes the design and implementation of an Agent-Based Model (ABM) used to simulate land use change on household farms in the Northern Ecuadorian Amazon (NEA) The ABM simulates decision-making processes at the household level that is examined through a longitudinal socioeconomic and demographic survey that was conducted in 1990 and 1999 Geographic Information Systems (GIS) are used to establish spatial relationships between farms and their environment while classified Landsat Thematic Mapper (TM) imagery is used to set initial land-use/land-cover conditions for the spatial simulation assess from-to land-use/land-cover change patterns and describe trajectories of land use change at the farm and landscape levels Results from prior studies in the NEA provide insights into the key social and ecological variables describe human behavioral functions and examine population-environment interactions that are linked to deforestation and agricultural extensification population migration and demographic change Within the architecture of the model agents are classified as active or passive The model comprises four modules i e initialization demography agriculture and migration that operate individually but are linked through key household processes The main outputs of the model include a spatially-explicit representation of the land use/land cover on survey and non-survey farms and at the landscape level for each annual time-step as well as simulated socio-economic and demographic characteristics of households and communities The work describes the design and implementation of the model and how population-environment interactions can be addressed in a frontier setting The paper contributes to land change science by examining important pattern-process relations advocating a spatial modeling approach that is capable of synthesizing fundamental relationships at the farm level and links people and environment in complex ways (C) 2010 Elsevier Ltd All rights reserved | |||||
BibTeX:
@article{mena_land_2011, author = {Mena, Carlos F. and Walsh, Stephen J. and Frizzelle, Brian G. and Yao, Xiaozheng and Malanson, George P.}, title = {Land use change on household farms in the Ecuadorian Amazon Design and implementation of an agent-based model}, journal = {Applied Geography}, year = {2011}, volume = {31}, number = {1}, pages = {210--222}, url = {://WOS:000285661100021}, doi = {https://doi.org/10.1016/j.apgeog.2010.04.005} } |
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Melo, V. and Sá, T. | Variação temporal de nutrientes na água escorrida pelo caule em floresta primária no nordeste do Pará, Brasil [BibTeX] |
2002 | Acta Amazonica Vol. 32, pp. 605-612 |
article | |
BibTeX:
@article{melo_variacao_2002, author = {Melo, V.S. and Sá, T.D.A.}, title = {Variação temporal de nutrientes na água escorrida pelo caule em floresta primária no nordeste do Pará, Brasil}, journal = {Acta Amazonica}, year = {2002}, volume = {32}, pages = {605--612} } |
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Melo, A., Silva, C., Piedade, M., Ferreira CS., R. and Franco | Seed germination and seedling development in response to submergence in tree species of the Central Amazonian floodplains [BibTeX] |
2015 | AOB Plants | article | |
BibTeX:
@article{melo_seed_2015, author = {Melo, AC; Silva, CO; Piedade, MTF; Ferreira, CS., RB; Franco}, title = {Seed germination and seedling development in response to submergence in tree species of the Central Amazonian floodplains}, journal = {AOB Plants}, year = {2015} } |
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Melo, N., Guyot J-L., E. and Filizola | Estudo comparativo de índices morfométricos nas bacias dos rios JURUÁ e PURUS Região Amazônica [BibTeX] |
2014 | Ciência & Ambiente Vol. 44, pp. 71-86 |
article | |
BibTeX:
@article{melo_estudo_2014, author = {Melo, N.; Guyot, J-L., E; Filizola}, title = {Estudo comparativo de índices morfométricos nas bacias dos rios JURUÁ e PURUS Região Amazônica}, journal = {Ciência & Ambiente}, year = {2014}, volume = {44}, pages = {71--86} } |
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Mello, G.J., Biudes, M.S., Gomes, R.S.R., Machado, N.G., Pereira, A. and Nogueira, J.S. | Dimensão fractal de séries de variáveis micrometeorológicas em uma floresta inundável no Pantanal de Mato Grosso [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 125-136 |
article | |
BibTeX:
@article{mello_dimensao_2016, author = {Mello, G. J. and Biudes, M. S. and Gomes, R. S. R. and Machado, N. G. and Pereira, A.O. and Nogueira, J. S.}, title = {Dimensão fractal de séries de variáveis micrometeorológicas em uma floresta inundável no Pantanal de Mato Grosso}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {125--136} } |
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Melillo, J.M., Steudler, P.A., Feigl, B.J., Neill, C., Garcia, D., Piccolo, M.C., Cerri, C.C. and Tian, H. | Nitrous oxide emissions from forests and pastures of various ages in the Brazilian Amazon | 2001 | Journal of Geophysical Research-Atmospheres Vol. 106(D24), pp. 34179-34188 |
article | DOI URL |
Abstract: Nitrous oxide emissions from tropical forest soils are thought to account for 2,2-3.7 Tg N yr(-1) of the total annual global production of 10-17 Tg N yr(-1). Recent research suggests that clearing of tropical forest for pasture can increase N(2)O emissions but that the period of elevated emissions may be limited and fluxes from older pastures may be lower than from the original forest. Here we report N(2)O emissions from two land-use sequences in the Brazilian Amazon's state of Rondonia. Each sequence includes a forest and a set of pastures of different ages. One sequence contains a newly created pasture that we studied intensively through its first 2 years, including forest cutting, burning, and the planting of forage grasses. Emissions from the newly created pasture were about two and one half times the forest emissions during the first 2 years (5.0 kg N(2)O-N ha(-1) yr(-1) versus 1.9 kg N(2)O-N ha(-1) yr(-1)). Nitrous oxide fluxes from pastures older than 3 years were on average about one third lower than fluxes from uncut forest (1.4 kg N(2)O-N ha(-1) yr(-1) versus 1.9 kg N(2)O-N ha(-1) yr(-1)). The best predictor of N(2)O flux across the chronosequences was the magnitude of the NO(3) pool in the upper 10 cm of soil measured at the time of gas sampling. Using a simple cohort model combined with deforestation rates estimated from satellite images by Brazil's Instituto de Pesquisas Espaciais (INPE) for the period 1978 through 1997, we estimate that for the Brazilian Amazon the basin-wide flux of N(2)O-N from pasture soils was 0.06 Tg in 1997. This is similar to8% of the combined forest plus pasture flux of 0.78 Tg N(2)O-N we estimate for the Brazilian part of the basin in 1997. In the absence of any forest-to-pasture conversion in the Brazilian part of the basin, we estimate that the basin-wide flux of N(2)O-N would have been only slightly larger: 0.80 Tg in 1997. Through a second modeling analysis we estimate that for the whole of the Amazon Basin, including parts of the basin outside of Brazil, the N(2)O-N emissions from forests averaged 1.3 Tg yr(-1) over the period 1978-1995. | |||||
BibTeX:
@article{melillo_nitrous_2001, author = {Melillo, J. M. and Steudler, P. A. and Feigl, B. J. and Neill, C. and Garcia, D. and Piccolo, M. C. and Cerri, C. C. and Tian, H.}, title = {Nitrous oxide emissions from forests and pastures of various ages in the Brazilian Amazon}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2001}, volume = {106}, number = {D24}, pages = {34179--34188}, url = {://WOS:000173879800060}, doi = {https://doi.org/10.1029/2000jd000036} } |
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Melack, J.M., Novo, E.M.L.M., Forsberg, B.R., Piedade, M.T.F. and Maurice, L. | Floodplain Ecosystem Processes [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 525-542 |
incollection | |
BibTeX:
@incollection{m_keller_floodplain_2009, author = {Melack, John M. and Novo, Evlyn M. L. M. and Forsberg, Bruce R. and Piedade, Maria T. F. and Maurice, Laurence}, title = {Floodplain Ecosystem Processes}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {525--542} } |
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Melack, J.M., Kasper, D., Amaral, J.H., Barbosa, P.M. and Forsberg, B.R. | Limnological perspectives on conservation of floodplain lakes in the Amazon basin | 2021 | Aquatic Conservation: Marine and Freshwater Ecosystems Vol. 31(5), pp. 1041-1055 |
article | DOI URL |
Abstract: Abstract Limnological aspects of Amazon floodplain lakes are examined in the context of aquatic conservation. A prerequisite to detecting and evaluating changes that could threaten the ecological health and organisms in floodplain lakes is understanding variation under present conditions. Based on one of the few studies with regular measurements over 2 years, chlorophyll, total phosphorus, dissolved oxygen, transparency, and total suspended solids in Lake Janauacá indicate that the lake is naturally quite variable with a mesotrophic to eutrophic status. Direct threats to ecological health of floodplain lakes include mining operations that can increase turbidity and trace metals and reduce nutritional quality of sediments. Mercury contamination and methylation leads to bioaccumulation in aquatic organisms. Deforestation in uplands increases nitrogen and phosphorus inputs to floodplain lakes and can alter trophic status. Deforestation in floodable forests alters the habitat and food of the fish that inhabit these forests. Cumulative limnological responses as catchments are altered by urban, agricultural, and industrial developments, and as inundation is altered by changes in climate and construction of dams, have major implications for the ecology of floodplain lakes. To improve understanding and management of threats to the conservation of aquatic Amazon biota and ecosystems requires considerably expanded and coordinated research and community-based management that includes the spectrum of floodplain lakes throughout the basin. | |||||
BibTeX:
@article{melack_limnological_2021, author = {Melack, John M. and Kasper, Daniele and Amaral, João H.F. and Barbosa, Pedro M. and Forsberg, Bruce R.}, title = {Limnological perspectives on conservation of floodplain lakes in the Amazon basin}, journal = {Aquatic Conservation: Marine and Freshwater Ecosystems}, year = {2021}, volume = {31}, number = {5}, pages = {1041--1055}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aqc.3556}, doi = {https://doi.org/10.1002/aqc.3556} } |
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Melack, J.M., Hess, L.L., Gastil, M., Forsberg, B.R., Hamilton, S.K., Lima, I.B.T. and Novo, E. | Regionalization of methane emissions in the Amazon Basin with microwave remote sensing | 2004 | Global Change Biology Vol. 10(5), pp. 530-544 |
article | DOI URL |
Abstract: sWetlands of the Amazon River basin are globally significant sources of atmospheric methane. Satellite remote sensing (passive and active microwave) of the temporally varying extent of inundation and vegetation was combined with field measurements to calculate regional rates of methane emission for Amazonian wetlands. Monthly inundation areas for the fringing floodplains of the mainstem Solimoes/Amazon River were derived from analysis of the 37 GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer from 1979 to 1987. L-band synthetic aperture radar data (Japanese Earth Resources Satellite-1) were used to determine inundation and wetland vegetation for the Amazon basin (textless500 m elevation) at high (May-June 1996) and low water (October 1995). An extensive set of measurements of methane emission is available from the literature for the fringing floodplains of the central Amazon, segregated into open water, flooded forest and floating macrophyte habitats. Uncertainties in the regional emission rates were determined by Monte Carlo error analyses that combined error estimates for the measurements of emission and for calculations of inundation and habitat areas. The mainstem Solimoes/Amazon floodplain (54-70degreesW) emitted methane at a mean annual rate of 1.3 Tg C yr(-1), with a standard deviation (SD) of the mean of 0.3 Tg C yr(-1); 67% of this range in uncertainty is owed to the range in rates of methane emission and 33% is owed to uncertainty in the areal estimates of inundation and vegetative cover. Methane emission from a 1.77 million square kilometers area in the central basin had a mean of 6.8 Tg C yr(-1) with a SD of 1.3 Tg C yr(-1). If extrapolated to the whole basin below the 500 m contour, approximately 22 Tg C yr(-1) is emitted; this mean flux has a greenhouse warming potential of about 0.5 Pg C as CO2. Improvement of these regional estimates will require many more field measurements of methane emission, further examination of remotely sensed data for types of wetlands not represented in the central basin, and process-based models of methane production and emission. | |||||
BibTeX:
@article{melack_regionalization_2004, author = {Melack, J. M. and Hess, L. L. and Gastil, M. and Forsberg, B. R. and Hamilton, S. K. and Lima, I. B. T. and Novo, Emlm}, title = {Regionalization of methane emissions in the Amazon Basin with microwave remote sensing}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {530--544}, url = {://WOS:000221421600002}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00763.x} } |
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Melack, J.M. | Aquatic Ecosystems [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 119-148 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_aquatic_2016, author = {Melack, John M.}, title = {Aquatic Ecosystems}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {119--148}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Meirink, J.F., Bergamaschi, P. and Krol, M.C. | Four-dimensional variational data assimilation for inverse modelling of atmospheric methane emissions: method and comparison with synthesis inversion | 2008 | Atmospheric Chemistry and Physics Vol. 8(21), pp. 6341-6353 |
article | URL |
Abstract: A four-dimensional variational (4D-Var) data assimilation system for inverse modelling of atmospheric methane emissions is presented. The system is based on the TM5 atmospheric transport model. It can be used for assimilating large volumes of measurements, in particular satellite observations and quasi-continuous in-situ observations, and at the same time it enables the optimization of a large number of model parameters, specifically grid-scale emission rates. Furthermore, the variational method allows to estimate uncertainties in posterior emissions. Here, the system is applied to optimize monthly methane emissions over a 1-year time window on the basis of surface observations from the NOAA-ESRL network. The results are rigorously compared with an analogous inversion by Bergamaschi et al. (2007), which was based on the traditional synthesis approach. The posterior emissions as well as their uncertainties obtained in both inversions show a high degree of consistency. At the same time we illustrate the advantage of 4D-Var in reducing aggregation errors by optimizing emissions at the grid scale of the transport model. The full potential of the assimilation system is exploited in Meirink et al. (2008), who use satellite observations of column-averaged methane mixing ratios to optimize emissions at high spatial resolution, taking | |||||
BibTeX:
@article{meirink_four-dimensional_2008, author = {Meirink, J. F. and Bergamaschi, P. and Krol, M. C.}, title = {Four-dimensional variational data assimilation for inverse modelling of atmospheric methane emissions: method and comparison with synthesis inversion}, journal = {Atmospheric Chemistry and Physics}, year = {2008}, volume = {8}, number = {21}, pages = {6341--6353}, url = {://WOS:000260927800002} } |
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Meir, P. and Woodward, F. | Amazonian rain forests and drought: response and vulnerability [BibTeX] |
2010 | New Phytologist Vol. 187(3), pp. 553-557 |
article | DOI URL |
BibTeX:
@article{meir_amazonian_2010, author = {Meir, P. and Woodward, F.I.}, title = {Amazonian rain forests and drought: response and vulnerability}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {553--557}, note = {Edition: 2010/07/28}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20659246 http://onlinelibrary.wiley.com/store/10.1111/j.1469-8137.2010.03390.x/asset/j.1469-8137.2010.03390.x.pdf?v=1&t=h6hwjwat&s=fce0f5bc1093de05663ed5d6196bfdb647ca990b}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03390.x} } |
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Meir, P., Wood, T.E., Galbraith, D.R., Brando, P.M., Costa, A.C.L.d., Rowland, L. and Ferreira, L.V. | Threshold Responses to Soil Moisture Deficit by Trees and Soil in Tropical Rain Forests: Insights from Field Experiments [BibTeX] |
2015 | BioScience Vol. 65(9), pp. 882-892 |
article | |
BibTeX:
@article{meir_threshold_2015, author = {Meir, Patrick and Wood, Tana E. and Galbraith, David R. and Brando, Paulo M. and Costa, Antonio C. L. da and Rowland, Lucy and Ferreira, Leandro V.}, title = {Threshold Responses to Soil Moisture Deficit by Trees and Soil in Tropical Rain Forests: Insights from Field Experiments}, journal = {BioScience}, year = {2015}, volume = {65}, number = {9}, pages = {882--892} } |
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Meir, P., Metcalfe, D.B., Costa, A.C.L. and Fisher, R.A. | The fate of assimilated carbon during drought: impacts on respiration in Amazon rainforests | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1849-1855 |
article | DOI URL |
Abstract: Interannual variations in CO2 exchange across Amazonia, as deduced from atmospheric inversions, correlate with El Nino occurrence. They are thought to result from changes in net ecosystem exchange and fire incidence that are both related to drought intensity. Alterations to net ecosystem production (NEP) are caused by changes in gross primary production (GPP) and ecosystem respiration (R-eco). Here, we analyse observations of the components of R-eco (leaves, live and dead woody tissue, and soil) to provide first estimates of changes in R-eco during short-term (seasonal to interannual) moisture limitation. Although photosynthesis declines if moisture availability is limiting, leaf dark respiration is generally maintained, potentially acclimating upwards in the longer term. If leaf area is lost, then short-term canopy-scale respiratory effluxes from wood and leaves are likely to decline. Using a moderate short-term drying scenario where soil moisture limitation leads to a loss of 0.5 m(2) m(-2) yr(-1) in leaf area index, we estimate a reduction in respiratory CO2 efflux from leaves and live woody tissue of 1.0 (+/-0.4) t C ha(-1) yr(-1). Necromass decomposition declines during drought, but mortality increases; the median mortality increase following a strong El Nino is 1.1% (n=46 tropical rainforest plots) and yields an estimated net short-term increase in necromass CO2 efflux of 0.13-0.18 t C ha(-1) yr(-1). Soil respiration is strongly sensitive to moisture limitation over the short term, but not to associated temperature increases. This effect is underestimated in many models but can lead to estimated reductions in CO2 efflux of 2.0 (+/-0.5) t C ha(-1) yr(-1). Thus, the majority of short-term respiratory responses to drought point to a decline in R-eco, an outcome that contradicts recent regional-scale modelling of NEP. NEP varies with both GPP and R-eco but robust moisture response functions are clearly needed to improve quantification of the role of R-eco in influencing regional-scale CO2 emissions from Amazonia. | |||||
BibTeX:
@article{meir_fate_2008, author = {Meir, P. and Metcalfe, D. B. and Costa, A. C. L. and Fisher, R. A.}, title = {The fate of assimilated carbon during drought: impacts on respiration in Amazon rainforests}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1849--1855}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500017}, doi = {https://doi.org/10.1098/rstb.2007.0021} } |
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Meir, P., Mencuccini, M. and Dewar, R. | Drought-related tree mortality - addressing the gaps in understanding and prediction [BibTeX] |
2015 | New Phytologist Vol. 207, pp. 28-33 |
article | |
BibTeX:
@article{meir_drought-related_2015, author = {Meir, P. and Mencuccini, M. and Dewar, RC.}, title = {Drought-related tree mortality - addressing the gaps in understanding and prediction}, journal = {New Phytologist}, year = {2015}, volume = {207}, pages = {28--33} } |
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Meir, P., Kruijt, B., Broadmeadow, M., Barbosa, E., Kull, O., Carswell, F., Nobre, A. and Jarvis, P.G. | Acclimation of photosynthetic capacity to irradiance in tree canopies in relation to leaf nitrogen concentration and leaf mass per unit area | 2002 | Plant Cell and Environment Vol. 25(3), pp. 343-357 |
article | DOI URL |
Abstract: The observation of acclimation in leaf photosynthetic capacity to differences in growth irradiance has been widely used as support for a hypothesis that enables a simplification of some soil-vegetation-atmosphere transfer (SVAT) photosynthesis models. The acclimation hypothesis requires that relative leaf nitrogen concentration declines with relative irradiance from the top of a canopy to the bottom, in 1 : 1 proportion. In combination with a light transmission model it enables a simple estimate of the vertical profile in leaf nitrogen concentration (which is assumed to determine maximum carboxylation capacity), and in combination with estimates of the fraction of absorbed radiation it also leads to simple 'big-leaf' analytical solutions for canopy photosynthesis. We tested how forests deviate from this condition in five tree canopies, including four broadleaf stands, and one needle-leaf stand: a mixed-species tropical rain forest, oak (Quercus petraea (Matt.) Liebl), birch (Betula pendula Roth), beech (Fagus sylvatica L.) and Sitka spruce (Picea sitchensis (Bong.) Carr). Each canopy was studied when fully developed (mid-to-late summer for temperate stands). Irradiance (Q, mumol m(-2) s(-1) ) was measured for 20 d using quantum sensors placed throughout the vertical canopy profile. Measurements were made to obtain parameters from leaves adjacent to the radiation sensors: maximum carboxylation and electron transfer capacity (V-a, J(a), mumol m(-2) s(-1) ), day respiration (R-da, mumol m(-2) s(-1) ), leaf nitrogen concentration (N-m, mg g(-1) ) and leaf mass per unit area (L-a, g m(-2) ). Relative to upper-canopy values, V-a declined linearly in 1 : 1 proportion with N-a. Relative V-a also declined linearly with relative Q, but with a significant intercept at zero irradiance (P textless 0.01). This intercept was strongly related to L-a of the lowest leaves in each canopy (P textless 0.01, r(2) = 0.98, n = 5). For each canopy, daily lnQ was also linearly related with lnV(a) P textless 0.05), and the intercept was correlated with the value for photosynthetic capacity per unit nitrogen (PUN: V-a/N-a, mumol g(-1) s(-1) ) of the lowest leaves in each canopy (Ptextless 0.05). V-a was linearly related with L-a and N-a (P textless 0.01), but the slope of the V-a : N-a relationship varied widely among sites. Hence, whilst there was a unique V-a :N-a ratio in each stand, acclimation in V-a to Q varied predictably with L-a of the lowest leaves in each canopy. The specific leaf area, L-m (cm(2) g(-1) ), of the canopy-bottom foliage was also found to predict carboxylation capacity (expressed on a mass basis; V-m, mumol g(-1) s(-1) ) at all sites (Ptextless 0.01). These results invalidate the hypothesis of full acclimation to irradiance, but suggest that L-a and L-m of the most light-limited leaves in a canopy are widely applicable indicators of the distribution of photosynthetic capacity with height in forests. | |||||
BibTeX:
@article{meir_acclimation_2002, author = {Meir, P. and Kruijt, B. and Broadmeadow, M. and Barbosa, E. and Kull, O. and Carswell, F. and Nobre, A. and Jarvis, P. G.}, title = {Acclimation of photosynthetic capacity to irradiance in tree canopies in relation to leaf nitrogen concentration and leaf mass per unit area}, journal = {Plant Cell and Environment}, year = {2002}, volume = {25}, number = {3}, pages = {343--357}, url = {://WOS:000174700600001 http://onlinelibrary.wiley.com/store/10.1046/j.0016-8025.2001.00811.x/asset/j.0016-8025.2001.00811.x.pdf?v=1&t=h6hwfo94&s=921ce1ea5d3ec4ac491040209cd716b1cff33c04}, doi = {https://doi.org/10.1046/j.0016-8025.2001.00811.x} } |
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Meir, P., Grace, J. and Miranda, A.C. | Leaf respiration in two tropical rainforests: constraints on physiology by phosphorus, nitrogen and temperature | 2001 | Functional Ecology Vol. 15(3), pp. 378-387 |
article | DOI URL |
Abstract: 1. Leaf respiration is a major component of the terrestrial carbon cycle, but is poorly quantified for tropical forests. We measured dark respiration, R, and nutrient concentration (nitrogen, N and phosphorus, P) of leaves within two forest canopies: in Reserva Jaru, south-west Brazil; and Mbalmayo Reserve, central Cameroon. The data, expressed on a leaf area basis (R(a), N(a), P(a)) and a leaf mass basis (R(m), N(m), P(m)), were used to quantify the temperature sensitivity of R and to test the hypothesis that leaf metabolism is more strongly constrained by phosphorus than by nitrogen in these lowland rainforests. 2. Leaf respiration rate (R(a), at 25 degreesC) at Jaru was nearly half that at Mbalmayo (the range in R(a) from near the ground to the upper canopy was 0.11-0.78 mu mol m(-2) s(-1) at Jaru versus 0.22-1.19 mu mol m(-2) s(-1) at Mbalmayo), and the mean Q(10) for respiration at each site was 2.3 +/- 0.9 (1 SD) and 2.0 +/- 0.5 (1 SD), respectively. There were significant differences (P textless 0.01) between sites in leaf phosphorus concentration, but not in leaf nitrogen concentration: P(m) was very low at Jaru (0.2-0.7 mg g(-1)) but higher at Mbalmayo (0.5-2.4 mg g(-1)), whilst N(m) was similar at both forests (10-45 mg g(-1)). 3. R(m) was not significantly associated with canopy position or specific leaf area (SLA, m(2) g(-1)) in either forest, but a significant relationship between SLA and N(m) was found for both sites (P textless 0.05), consistent with existing data. At Jaru, R(m) was strongly related to P(m) (P textless 0.001) and less strongly related to N(m) (P textless 0.05), but at Mbalmayo, R(m) was not significantly related to either P(m) or N(m). 4. R(a) was linearly related to N(a) and P(a) at both sites (P textless 0.01), principally because of changes in leaf mass per area (LMA, g m(-2)) associated with canopy position. At Mbalmayo, LMA explained 70% of the variation in R(a), but only 20% at Jaru. For Jaru, the strongest relationship with R(a) was obtained by combining LMA with P(m) in a multiple regression (r(2) = 0.53); further inclusion of N(m) did not improve the regression. At Mbalmayo neither N(m) or P(m) improved the regression of R(a) on LMA. 5. These results indicate a strong influence of LMA on the relative rates of R(a) within the vertical gradient of each canopy. They also suggest that at Jaru P(m) constrains respiration more strongly than N(m), and further, that the very low P(m) at Jaru may explain the lower absolute values of respiration there relative to Mbalmayo, where P(m) was higher. The leaves at both sites are typical of lowland tropical rainforests in not having particularly low N(m), and consistent with this, N(m) was a weaker predictor of respiration than P(m) or LMA. | |||||
BibTeX:
@article{meir_leaf_2001, author = {Meir, P. and Grace, J. and Miranda, A. C.}, title = {Leaf respiration in two tropical rainforests: constraints on physiology by phosphorus, nitrogen and temperature}, journal = {Functional Ecology}, year = {2001}, volume = {15}, number = {3}, pages = {378--387}, url = {://WOS:000169131300012}, doi = {https://doi.org/10.1046/j.1365-2435.2001.00534.x} } |
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Meir, P. and Grace, J. | Scaling relationships for woody tissue respiration in two tropical rain forests | 2002 | Plant Cell and Environment Vol. 25(8), pp. 963-973 |
article | DOI URL |
Abstract: The relationship between gross primary productivity (GPP) and net primary productivity (NPP) is not fully understood. One of the uncertainties relevant to this issue is the magnitude of woody tissue respiration. Although some data exist for temperate and boreal zones, measurements of woody tissue respiration in tropical forests are sparse. We made in situ chamber measurements of woody tissue respiration in two tropical rain forests, one in the Brazilian Amazon (Reserva Jaru) and one in Central Cameroon (Mbalmayo Reserve). We made measurements on a wide range of species at each site and over a range of stem diameters from 0.02 to 1.4 m. The rate of efflux of carbon dioxide (CO2 ) from bark at 25 degreesC, R (t) , varied from 0.1 to 5.2 mu mol m(-2) s(-1) across the two sites, and the efflux was related to both volume and surface area components of the measured stem sections. The temperature response in R (t) was slightly higher at Jaru than at Mbalmayo, with Q (10) values of 1.8 (+/- 0.1 SE) and 1.6 (+/- 0.1 SE), respectively. A log-log regression showed that R (t) was significantly related to stem diameter, D (P textless 0.001; r (2) = 0.58-0.62) and was significantly higher at Mbalmayo than at Jaru (P textless 0.001), but that the rate of increase in R (t) with stem diameter, D , was similar between sites. At the Mbalmayo site, tree growth measurements made over a 4 month period were used to make two estimates of the maintenance (R (m) ) and construction (R (c) ) components of respiration embedded in R (t) . The two methods agreed closely, suggesting that R (m) was approximately 80% of R (c) at this site. R (m) could be strongly related to D using a sigmoidal relationship that described both surface area and volume components as sources of respiratory CO2 (r (2) = 0.71). This functional model was combined with inventory, growth and climate data for the Mbalmayo site to make a first estimate of annual above-ground woody tissue respiration, R (A) , which was 257 (+/- 18 SE) g C m(-2) year(-1) . This value corresponds to approximately 10% of GPP, slightly lower than that found for another tropical rain forest, but higher than for temperate forests. When combined with data from six other sites in tropical, temperate and boreal settings, a very strong relationship was found between R (A) and leaf area index (LAI), and between R (A) /GPP and LAI (P textless 0.001, r (2) = 0.98). This indicates that R (A) exerts an appreciable constraint on NPP and that this constraint varies closely with LAI across widely differing types of woody vegetation. | |||||
BibTeX:
@article{meir_scaling_2002, author = {Meir, P. and Grace, J.}, title = {Scaling relationships for woody tissue respiration in two tropical rain forests}, journal = {Plant Cell and Environment}, year = {2002}, volume = {25}, number = {8}, pages = {963--973}, url = {://WOS:000176924000003}, doi = {https://doi.org/10.1046/j.1365-3040.2002.00877.x} } |
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Meir, P., Cox, P. and Grace, J. | The influence of terrestrial ecosystems on climate | 2006 | Trends in Ecology & Evolution Vol. 21(5), pp. 254-260 |
article | DOI URL |
Abstract: Terrestrial ecosystems influence climate by affecting how much solar energy is absorbed by the land surface and by exchanging climatically important gases with the atmosphere. Recent model analyses show widespread qualitative agreement that terrestrial ecological processes will have a net positive feedback effect on 21st-century global warming, and, therefore, cannot be ignored in climate-change projections. However, the quantitative uncertainty in the net feedback is large. The uncertainty in 21st-century carbon dioxide emissions resulting from terrestrial carbon cycle-climate feedbacks is second in magnitude only to the uncertainty in anthropogenic emissions. We estimate that this translates into an uncertainty in global warming owing to the land surface of 1.5 degrees degrees C by 2100. We also emphasise the need to improve our understanding of terrestrial ecological processes that influence land-atmosphere interactions at relatively long timescales (decadal-century) as well as at shorter intervals (e.g. hourly). | |||||
BibTeX:
@article{meir_influence_2006, author = {Meir, Patrick and Cox, Peter and Grace, John}, title = {The influence of terrestrial ecosystems on climate}, journal = {Trends in Ecology & Evolution}, year = {2006}, volume = {21}, number = {5}, pages = {254--260}, note = {Edition: 2006/05/16}, url = {://WOS:000238013500006}, doi = {https://doi.org/10.1016/j.tree.2006.03.005} } |
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Meir, P., Brando, P.M., Nepstad, D., Vasconcelos, S., Costa, A.C.L., Davidson, E., Almeida, S., Fisher, R.A., Sotta, E.D., Zarin, D. and Cardinot, G. | The Effects of Drought on Amazonian Rain Forests [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 429-450 |
incollection | |
BibTeX:
@incollection{m_keller_effects_2009, author = {Meir, P. and Brando, P. M. and Nepstad, D. and Vasconcelos, S. and Costa, A. C. L. and Davidson, E. and Almeida, S. and Fisher, R. A. and Sotta, E. D. and Zarin, D. and Cardinot, G.}, title = {The Effects of Drought on Amazonian Rain Forests}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {429--450} } |
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Medvigy, D., Walko, R.L. and Avissar, R. | Modeling interannual variability of the Amazon hydroclimate | 2008 | Geophysical Research Letters Vol. 35(15) |
article | DOI URL |
Abstract: El Nino/Southern Oscillation (ENSO) strongly influences the interannual variability of Amazon hydroclimate. But current global climate models are unable to represent the associated variability, raising the question of their aptitude to simulate current and changing climate in that region. We explore this critical issue with the Ocean-Land-Atmosphere Model (OLAM), a new Earth System Model (ESM) capable of simulating regions like mountain ranges at high resolution while efficiently simulating the rest of the world at coarser resolution. We find that simulations representing the Andes at resolutions coarser than 100 km lead to a 'reverse' ENSO effect, with large precipitation rates in the Amazon during ENSO events. In contrast, the model correctly simulates the ENSO dry anomaly provided the Andes are simulated at resolutions finer than 100 km. Furthermore, we find that the grid mesh over the Andes has important implications for ENSO teleconnections, especially over the continents. | |||||
BibTeX:
@article{medvigy_modeling_2008, author = {Medvigy, D. and Walko, R. L. and Avissar, R.}, title = {Modeling interannual variability of the Amazon hydroclimate}, journal = {Geophysical Research Letters}, year = {2008}, volume = {35}, number = {15}, url = {://WOS:000258509700008}, doi = {https://doi.org/10.1029/2008gl034941} } |
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Medvigy, D., Moorcroft, P.R., Avissar, R. and Walko, R.L. | Mass conservation and atmospheric dynamics in the regional atmospheric modeling system (RAMS) | 2005 | Environmental Fluid Mechanics Vol. 5(1-2), pp. 109-134 |
article | DOI URL |
Abstract: This paper examines the spatio-temporal patterns of atmospheric carbon dioxide transport predicted by the Regional Atmospheric Modeling System (RAMS). Forty-eight hour simulations over northern New England incorporating a simple representation of the diurnal summertime surface carbon dioxide forcing arising from biological activity indicate that, in its native formulation, RAMS exhibits a significant degree of mass non-conservation. Domain-wide rates of non-physical mass gain and mass loss are as large as three percent per day which translates into approximately eleven parts per million per day for carbon dioxide - enough to rapidly dilute the signature of carbon dioxide fluxes arising from biological activity. Analysis shows that this is due to the approximation used by RAMS to compute the Exner function. Substitution of the exact, physically complete equation improves mass conservation by two orders of magnitude. In addition to greatly improving mass conservation, use of the complete Exner function equation has a substantial impact on the spatial pattern of carbon dioxide predicted by the model, yielding predictions differing from a conventional RAMS simulation by as much as forty parts per million. Such differences have important implications both for comparisons of modeled atmospheric carbon dioxide concentrations to observations and for carbon dioxide inversion studies, which use estimates of atmospheric transport of carbon dioxide in conjunction with measurements of atmospheric carbon dioxide concentrations to infer the spatio-temporal distribution of surface carbon dioxide fluxes. Furthermore, use of the complete Exner function equation affects the vertical velocity and water mixing ratio fields, causing significant changes in accumulated precipitation over the region. | |||||
BibTeX:
@article{medvigy_mass_2005, author = {Medvigy, D. and Moorcroft, P. R. and Avissar, R. and Walko, R. L.}, title = {Mass conservation and atmospheric dynamics in the regional atmospheric modeling system (RAMS)}, journal = {Environmental Fluid Mechanics}, year = {2005}, volume = {5}, number = {1-2}, pages = {109--134}, url = {://WOS:000229939700005}, doi = {https://doi.org/10.1007/s10652-005-5275-5} } |
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Medeiros, P., Ferreira, l. and Costa, A. | O impacto do estresse hídrico artificial na comunidade de samambaias e licófitas em um sub-bosque de floresta ombrófila na Amazônia oriental. [BibTeX] |
2014 | Boletim do Museu Paraense Emílio Goeldi. Ciências Naturais Vol. 9, pp. 223-230 |
article | |
BibTeX:
@article{medeiros_o_2014, author = {Medeiros, P.S. and Ferreira, l.V. and Costa, A.C.L.}, title = {O impacto do estresse hídrico artificial na comunidade de samambaias e licófitas em um sub-bosque de floresta ombrófila na Amazônia oriental.}, journal = {Boletim do Museu Paraense Emílio Goeldi. Ciências Naturais}, year = {2014}, volume = {9}, pages = {223--230} } |
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Medeiros, P., Seidel, M., Ward, N., Carpenter, E., Gomes, H., Niggemann, J., Krusche, A., Richey, J., Yager, P. and Dittmar, T. | Fate of the Amazon River dissolved organic matter in the tropical Atlantic Ocean [BibTeX] |
2015 | Global Biogeochemical Cycles Vol. 29(5), pp. 677-690 |
article | DOI |
BibTeX:
@article{medeiros_fate_2015, author = {Medeiros, P.M. and Seidel, M. and Ward, N.D. and Carpenter, E.J. and Gomes, H.R. and Niggemann, J. and Krusche, A.V. and Richey, J.E. and Yager, P.L. and Dittmar, T.}, title = {Fate of the Amazon River dissolved organic matter in the tropical Atlantic Ocean}, journal = {Global Biogeochemical Cycles}, year = {2015}, volume = {29}, number = {5}, pages = {677--690}, doi = {https://doi.org/10.1002/2015GB005115} } |
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McGuire, A.D., Sitch, S., Clein, J.S., Dargaville, R., Esser, G., Foley, J., Heimann, M., Joos, F., Kaplan, J., Kicklighter, D.W., Meier, R.A., Melillo, J.M., Moore, B., Prentice, I.C., Ramankutty, N., Reichenau, T., Schloss, A., Tian, H., Williams, L.J. and Wittenberg, U. | Carbon balance of the terrestrial biosphere in the twentieth century: Analyses of CO2, climate and land use effects with four process-based ecosystem models | 2001 | Global Biogeochemical Cycles Vol. 15(1), pp. 183-206 |
article | DOI URL |
Abstract: The concurrent effects of increasing atmospheric CO2 concentration, climate variability, and cropland establishment and abandonment on terrestrial carbon storage between 1920 and 1992 were assessed using a standard simulation protocol with four process-based terrestrial biosphere models. Over the long-term (1920-1992), the simulations yielded a time history of terrestrial uptake that is consistent (within the uncertainty) with a long-term analysis based on ice core and atmospheric CO2 data. Up to 1958, three of four analyses indicated a net release of carbon from terrestrial ecosystems to the atmosphere caused by cropland establishment. After 1958, all analyses indicate a net uptake of carbon by terrestrial ecosystems, primarily because of the physiological effects of rapidly rising atmospheric CO2. During the 1980s the simulations indicate that terrestrial ecosystems stored between 0.3 and 1.5 Pg C yr(-1), which is within the uncertainty of analysis based on CO2 and O-2 budgets. Three of the four models indicated tin accordance with O-2 evidence) that the tropics were approximately neutral while a net sink existed in ecosystems north of the tropics. Although all of the models agree that the long-term effect of climate on carbon storage has been small relative to the effects of increasing atmospheric CO2 and land use, the models disagree as to whether climate variability and change in the twentieth century has promoted carbon storage or release. Simulated interannual variability from 1958 generally reproduced the El Nino/Southern Oscillation (ENSO)-scale variability in the atmospheric CO2 increase, but there were substantial differences in the magnitude of interannual variability simulated by the models. The analysis of the ability of the models to simulate the changing amplitude of the seasonal cycle of atmospheric CO2 suggested that the observed trend may be a consequence of CO2 effects, climate variability, land use changes, or a combination of these effects. The next steps for improving the process-based simulation of historical terrestrial carbon include (1) the transfer of insight gained from stand-level process studies to improve the sensitivity of simulated carbon storage responses to changes in CO2 and climate, (2) improvements in the data sets used to drive the models so that they incorporate the timing, extent, and types of major disturbances, (3) the enhancement of the models so that they consider major crop types and management schemes, (4) development of data sets that identify the spatial extent of major crop types and management schemes through time, and (5) the consideration of the effects of anthropogenic nitrogen deposition. The evaluation of the performance of the models in the context of a more complete consideration of the factors influencing historical terrestrial carbon dynamics is important for reducing uncertainties in representing the role of terrestrial ecosystems in future projections of the Earth system. | |||||
BibTeX:
@article{mcguire_carbon_2001, author = {McGuire, A. D. and Sitch, S. and Clein, J. S. and Dargaville, R. and Esser, G. and Foley, J. and Heimann, M. and Joos, F. and Kaplan, J. and Kicklighter, D. W. and Meier, R. A. and Melillo, J. M. and Moore, B. and Prentice, I. C. and Ramankutty, N. and Reichenau, T. and Schloss, A. and Tian, H. and Williams, L. J. and Wittenberg, U.}, title = {Carbon balance of the terrestrial biosphere in the twentieth century: Analyses of CO2, climate and land use effects with four process-based ecosystem models}, journal = {Global Biogeochemical Cycles}, year = {2001}, volume = {15}, number = {1}, pages = {183--206}, url = {://WOS:000167848800015 http://www.agu.org/pubs/crossref/2001/2000GB001298.shtml}, doi = {https://doi.org/10.1029/2000gb001298} } |
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McGroddy, M.E., Silver, W.L., de Oliveira Jr., R.C., de Mello, W.Z. and Keller, M. | Retention of phosphorus in highly weathered soils under a lowland Amazonian forest ecosystem | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113(G4) |
article | DOI URL |
Abstract: The low available phosphorus ( P) pools typical of highly weathered tropical forest soils are thought to result from a combination of export of phosphorus via erosion and leaching as well as chemical reactions resulting in physically and chemically protected P compounds. Despite the low apparent P availability, these soils support some of the highest terrestrial net primary productivity globally. We followed different P fractions after P additions to two soil types, sandy loam and sandy clay, over 1 year in a lowland Amazonian forest. Of all the soil P fractions measured, only the NaHCO(3) and NaOH extractable fractions showed a significant increase following P additions, and this occurred only in sandy clays (+ 56.9 +/- 15.1 kg ha(-1) and + 2.8 +/- 1.5 kg ha(-1), respectively). Our results indicate that intermediate rather than recalcitrant pools are the dominant fate of added P over an annual timescale even in fine-textured soils. Fine root and forest floor P pools increased more in the sandy loams following P additions suggesting a larger biotic P sink in these soils. Leaching of inorganic P from the surface soils was an unexpected and significant fate of added P in both soil types ( 9 +/- 3% in the sandy loams, 2 +/- 1% in the sandy clays). Significantly more of the added P was retained in the sandy clay soils than in the sandy loams ( 69 +/- 20% versus 33 +/- 7%) over the 1-year period. | |||||
BibTeX:
@article{mcgroddy_retention_2008, author = {McGroddy, M. E. and Silver, W. L. and de Oliveira, Jr., R. C. and de Mello, W. Z. and Keller, M.}, title = {Retention of phosphorus in highly weathered soils under a lowland Amazonian forest ecosystem}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, number = {G4}, url = {://WOS:000260599800002}, doi = {https://doi.org/10.1029/2008jg000756} } |
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McGroddy, M.E., Silver, W.L. and de Oliveira, R.C. | The effect of phosphorus availability on decomposition dynamics in a seasonal lowland Amazonian forest | 2004 | Ecosystems Vol. 7(2), pp. 172-179 |
article | DOI URL |
Abstract: Once the weathering of parent material ceases to supply significant inputs of phosphorus (P), vegetation depends largely on the decomposition of litter and soil organic matter and the associated mineralization of organic P forms to provide an adequate supply of this essential nutrient. At the same time, the decomposition of litter is often characterized by the immobilization of nutrients, suggesting that nutrient availability is a limiting factor for this process. Immobilization temporally decouples nutrient mineralization from decomposition and may play an important role in nutrient retention in low-nutrient ecosystems. In this study, we used a common substrate to study the effects of native soil P availability as well as artificially elevated P availability on litter decomposition rates in a lowland Amazonian rain forest on highly weathered soils. Although both available and total soil P pools varied almost three fold across treatments, there was no significant difference in decomposition rates among treatments. Decomposition was rapid in all treatments, with approximately 50% of the mass lost over the 11-month study period. Carbon (C) and nitrogen (N) remaining and C:N ratios were the most effective predictors of amount of mass remaining at each time point in all treatments. Fertilized treatments showed significant amounts of P immobilization (P textless 0.001). By the final collection point, the remaining litter contained a quantity equivalent to two-thirds of the initial P and N, even though only half of the original mass remained. In these soils, immobilization of nutrients in the microbial biomass, late in the decomposition process, effectively prevents the loss of essential nutrients through leaching or occlusion in the mineral soil. | |||||
BibTeX:
@article{mcgroddy_effect_2004, author = {McGroddy, M. E. and Silver, W. L. and de Oliveira, R. C.}, title = {The effect of phosphorus availability on decomposition dynamics in a seasonal lowland Amazonian forest}, journal = {Ecosystems}, year = {2004}, volume = {7}, number = {2}, pages = {172--179}, url = {://WOS:000220567000005}, doi = {https://doi.org/10.1007/s10021-003-0208-y} } |
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McGrath, D.A., Smith, C.K., Gholz, H.L. and Oliveira, F.D. | Effects of land-use change on soil nutrient dynamics in Amazonia | 2001 | Ecosystems Vol. 4(7), pp. 625-645 |
article | DOI URL |
Abstract: Over the past several decades, the conversion of native forest to agricultural land uses has accelerated across the Amazon Basin. Despite a growing body of research on nutrient dynamics in Amazonian primary forest and forest-derived land uses, the effects of widespread land-use change on nutrient contents and cycles in soil and vegetation are not well understood. We reviewed over 100 studies conducted in Amazonia over the past 40 years on nutrient dynamics in natural forests and forest-derived land uses (pasture, shifting cultivation, and tree plantations). Our objectives were to compare soil data from land uses across Amazonia and identify any gaps in our present knowledge that might offer direction for future research. Specifically, by analyzing data we tested the following five widely cited hypotheses concerning the effects of land-use change on soil properties compiled from 39 studies in multifactorial ANOVA models; (a) soil pH, effective cation exchange capacity (ECEC), and exchangeable calcium (Ca) concentrations rise and remain elevated following the slash-and-burn conversion of forest to pasture or crop fields; (b) soil contents of total carbon (C), nitrogen (N), and inorganic readily extractable (that is, Bray, Mehlich I, or resin) phosphorus (P(i)) decline following forest-to-pasture conversion; (c) soil concentrations of total C, N, and P(i) increase in secondary forests with time since abandonment of agricultural activities; (d) soil nutrient conditions under all tree-dominated land-use systems (natural or not) remain the same; and (e) higher efficiencies of nutrient utilization occur where soil nutrient pools are lower. Following the conversion of Amazonian forest to pasture or slash-and-burn agriculture, we found a significant and lasting effect on soil pH, bulk density, and exchangeable Ca concentrations. Unlike the other three land uses studied, concentrations of extractable soil P(i) were equally low in both forest and pastures of all age classes, which demonstrates that postburning pulses in soil P(i) concentration following a slash-and-burn decrease rapidly after forest-to-pasture conversion, perhaps due to accumulation in organic P fractions. Neither the concentrations nor the contents of total C and N appeared to change greatly on a regionwide basis as a result of forest-to-pasture conversion, but surface soil C:N ratios in 5-year-old pastures were significantly higher than those in older pastures, suggesting changes in the soil concentrations of at least one of these elements with time after pasture creation. Pasture soils did have higher total C and N concentrations than land uses such as annual cropping and secondary forest fallow, indicating that soil C and N maintenance and/or accumulation following forest conversion may be greater in pastures than in these other two land uses. The low concentrations of C and N in shifting cultivation soils appear to persist for many years in secondary forests regenerating from abandoned crop fields, suggesting that the recuperation of soil losses of C and N resulting during no-input annual cropping is slower than previously thought. Soil C, N and P concentrations were strongly related to clay content. Across all land uses, efficiencies of N, P, and Ca use (estimated as the inverse of litterfall N, P, and Ca contents) were not related to the sizes of their soil pools. More work is needed to test and standardize P extraction procedures that more accurately reflect plant availability. Few studies have been conducted to determine the role of organic P fractions and dissolved organic N (DON) in the elemental cycles of both natural and managed systems in this region. In general, we recommend further study of annual and perennial cropping systems, as well as more detailed examination of managed pastures and fallows, and secondary forests originating from various disturbances, since the intensity of previous land use likely determines the degree of soil degradation and the rate of subsequent secondary regrowth. | |||||
BibTeX:
@article{mcgrath_effects_2001, author = {McGrath, D. A. and Smith, C. K. and Gholz, H. L. and Oliveira, F. D.}, title = {Effects of land-use change on soil nutrient dynamics in Amazonia}, journal = {Ecosystems}, year = {2001}, volume = {4}, number = {7}, pages = {625--645}, url = {://WOS:000172503300002}, doi = {https://doi.org/10.1007/s10021-001-0033-0} } |
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McFiggans, G., Artaxo, P., Baltensperger, U., Coe, H., Facchini, M.C., Feingold, G., Fuzzi, S., Gysel, M., Laaksonen, A., Lohmann, U., Mentel, T.F., Murphy, D.M., O'Dowd, C.D., Snider, J.R. and Weingartner, E. | The effect of physical and chemical aerosol properties on warm cloud droplet activation | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 2593-2649 |
article | URL |
Abstract: The effects of atmospheric aerosol on climate forcing may be very substantial but are quantified poorly at present; in particular, the effects of aerosols on cloud radiative properties, or the "indirect effects" are credited with the greatest range of uncertainty amongst the known causes of radiative forcing. This manuscript explores the effects that the composition and properties of atmospheric aerosol can have on the activation of droplets in warm clouds, so potentially influencing the magnitude of the indirect effect. The effects of size, composition, mixing state and various derived properties are assessed and a range of these properties provided by atmospheric measurements in a variety of locations is briefly reviewed. The suitability of a range of process-level descriptions to capture these aerosol effects is investigated by assessment of their sensitivities to uncertainties in aerosol properties and by their performance in closure studies. The treatment of these effects within global models is reviewed and suggestions for future investigations are made. | |||||
BibTeX:
@article{mcfiggans_effect_2006, author = {McFiggans, G. and Artaxo, P. and Baltensperger, U. and Coe, H. and Facchini, M. C. and Feingold, G. and Fuzzi, S. and Gysel, M. and Laaksonen, A. and Lohmann, U. and Mentel, T. F. and Murphy, D. M. and O'Dowd, C. D. and Snider, J. R. and Weingartner, E.}, title = {The effect of physical and chemical aerosol properties on warm cloud droplet activation}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {2593--2649}, url = {://WOS:000238823900001} } |
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McDowell, N. | Deriving pattern from complexity in the processes underlying tropical forest drought impacts [BibTeX] |
2018 | New Phytologist Vol. 219(Editorial), pp. 841-844 |
article | |
BibTeX:
@article{mcdowell_deriving_2018, author = {McDowell, N.G.}, title = {Deriving pattern from complexity in the processes underlying tropical forest drought impacts}, journal = {New Phytologist}, year = {2018}, volume = {219}, number = {Editorial}, pages = {841--844} } |
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McDowell, N., Allen, C.D., Anderson-Teixeira, K., Brando, P., Brienen, R., Chambers, J., Christoffersen, B., Davies, S., Doughty, C., Duque, A., Espirito-Santo, F., Fisher, R., Fontes, C.G., Galbraith, D., Goodsman, D., Grossiord, C., Hartmann, H., Holm, J., Johnson, D.J., Kassim, A.R., Keller, M., Koven, C., Kueppers, L., Kumagai, T., Malhi, Y., McMahon, S.M., Mencuccini, M., Meir, P., Moorcroft, P., Muller-Landau, H.C., Phillips, O.L., Powell, T., Sierra, C.A., Sperry, J., Warren, J., Xu, C. and Xu, X. | Drivers and mechanisms of tree mortality in moist tropical forests | 2018 | New Phytologist Vol. 219(3), pp. 851-869 |
article | DOI URL |
Abstract: Summary Tree mortality rates appear to be increasing in moist tropical forests (MTFs) with significant carbon cycle consequences. Here, we review the state of knowledge regarding MTF tree mortality, create a conceptual framework with testable hypotheses regarding the drivers, mechanisms and interactions that may underlie increasing MTF mortality rates, and identify the next steps for improved understanding and reduced prediction. Increasing mortality rates are associated with rising temperature and vapor pressure deficit, liana abundance, drought, wind events, fire and, possibly, CO2 fertilization-induced increases in stand thinning or acceleration of trees reaching larger, more vulnerable heights. The majority of these mortality drivers may kill trees in part through carbon starvation and hydraulic failure. The relative importance of each driver is unknown. High species diversity may buffer MTFs against large-scale mortality events, but recent and expected trends in mortality drivers give reason for concern regarding increasing mortality within MTFs. Models of tropical tree mortality are advancing the representation of hydraulics, carbon and demography, but require more empirical knowledge regarding the most common drivers and their subsequent mechanisms. We outline critical datasets and model developments required to test hypotheses regarding the underlying causes of increasing MTF mortality rates, and improve prediction of future mortality under climate change. Contents Summary 852 I. Introduction 852 II. Increasing mortality rates in the Amazon Basin 854 III. Global and regional mortality drivers and mechanisms 855 IV. On the coupling of mortality drivers and mechanisms 859 V. Mitigating factors that may promote future survival 859 VI. The state of ESM simulations of moist tropical tree mortality 859 VII. Next steps 860 VIII. Conclusions 863 Acknowledgements 863 ORCID 863 References 863 | |||||
BibTeX:
@article{mcdowell_drivers_2018, author = {McDowell, Nate and Allen, Craig D. and Anderson-Teixeira, Kristina and Brando, Paulo and Brienen, Roel and Chambers, Jeff and Christoffersen, Brad and Davies, Stuart and Doughty, Chris and Duque, Alvaro and Espirito-Santo, Fernando and Fisher, Rosie and Fontes, Clarissa G. and Galbraith, David and Goodsman, Devin and Grossiord, Charlotte and Hartmann, Henrik and Holm, Jennifer and Johnson, Daniel J. and Kassim, Abd. Rahman and Keller, Michael and Koven, Charlie and Kueppers, Lara and Kumagai, Tomo'omi and Malhi, Yadvinder and McMahon, Sean M. and Mencuccini, Maurizio and Meir, Patrick and Moorcroft, Paul and Muller-Landau, Helene C. and Phillips, Oliver L. and Powell, Thomas and Sierra, Carlos A. and Sperry, John and Warren, Jeff and Xu, Chonggang and Xu, Xiangtao}, title = {Drivers and mechanisms of tree mortality in moist tropical forests}, journal = {New Phytologist}, year = {2018}, volume = {219}, number = {3}, pages = {851--869}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.15027}, doi = {https://doi.org/10.1111/nph.15027} } |
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McCracken, S.D., Brondizio, E.S., Nelson, D., Moran, E.F., Siqueira, A.D. and Rodriguez-Pedraza, C. | Remote sensing and GIS at farm property level: Demography and deforestation in the Brazilian Amazon | 1999 | Photogrammetric Engineering and Remote Sensing Vol. 65(11), pp. 1311-1320 |
article | URL |
Abstract: Analysis of remotely sensed data at the level of individual farm properties provides additional insights to those derived from a landscape approach. Property-level analysis was carried out by overlaying a property boundary grid in a GIS. Data were derived from aerial photographs for 1970 and 1978 and Landsat Thematic Mapper images for 1985, 1988, and 1991. The study area contains approximately 3,800 properties, but this paper is based on a subset of 398 properties in the Brazilian Amazon. Analysis at the property level found patterns of land-cover classes that reflect differences in farming strategies of households. Data analysis at the household level was useful in explaining apparent mature forest to advanced secondary succession degradation in three years, not readily apparent from landscape analysis of remotely sensed data. The change was due to property-specific selective logging and the spread of fire from pastures into the adjacent forest. | |||||
BibTeX:
@article{mccracken_remote_1999, author = {McCracken, S. D. and Brondizio, E. S. and Nelson, D. and Moran, E. F. and Siqueira, A. D. and Rodriguez-Pedraza, C.}, title = {Remote sensing and GIS at farm property level: Demography and deforestation in the Brazilian Amazon}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {1999}, volume = {65}, number = {11}, pages = {1311--1320}, url = {://WOS:000083477200013} } |
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Mayorga, E., Logsdon, M.G., Ballester, M.V.R. and Richey, J.E. | Estimating cell-to-cell land surface drainage paths from digital channel networks, with an application to the Amazon basin | 2005 | Journal of Hydrology Vol. 315(1-4), pp. 167-182 |
article | DOI URL |
Abstract: Cell-to-cell surface flow paths are commonly derived from gridded digital elevation models (DEM) by choosing the direction of steepest descent to one of the eight surrounding cells. However, adequate DEMs often are not available. We developed a topography-independent method for creating gridded, land and stream drainage direction maps based on corrected vector river networks. We applied it to the Digital Chart of the World river network in the Amazon basin gridded at 0.005 degrees resolution; in this basin, low relief and poor topographic data have prevented the effective use of DEM-based methods. We geo-registered 224 hydrographic gages against the processed network and compared extracted vs. published drainage areas. Drainage areas ranged from 227 to 4,620,000 km(2). Median relative error was 4.5%, increasing in smaller basins to 94% in basins textless= 2000 km(2). The effective limit of reliability may differ from 2000 km2 across the basin. The drainage direction map and derivative datasets represent an improvement over existing datasets for regional research in the Amazon basin. Methods exploiting vector networks complement terrain approaches, and combined they may yield advances in the automated extraction of drainage maps and handling of topologically realistic river systems. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{mayorga_estimating_2005, author = {Mayorga, E. and Logsdon, M. G. and Ballester, M. V. R. and Richey, J. E.}, title = {Estimating cell-to-cell land surface drainage paths from digital channel networks, with an application to the Amazon basin}, journal = {Journal of Hydrology}, year = {2005}, volume = {315}, number = {1-4}, pages = {167--182}, url = {://WOS:000233981000010}, doi = {https://doi.org/10.1016/j.jhydrol.2005.03.023} } |
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Mayorga, E., Aufdenkampe, A.K., Masiello, C.A., Krusche, A.V., Hedges, J.I., Quay, P.D., Richey, J.E. and Brown, T.A. | Young organic matter as a source of carbon dioxide outgassing from Amazonian rivers | 2005 | Nature Vol. 436(7050), pp. 538-541 |
article | DOI URL |
Abstract: Rivers are generally supersaturated with respect to carbon dioxide, resulting in large gas evasion fluxes that can be a significant component of regional net carbon budgets(1,2). Amazonian rivers were recently shown to outgas more than ten times the amount of carbon exported to the ocean in the form of total organic carbon or dissolved inorganic carbon(1). High carbon dioxide concentrations in rivers originate largely from in situ respiration of organic carbon(1-3), but little agreement exists about the sources or turnover times of this carbon(2,4,5). Here we present results of an extensive survey of the carbon isotope composition (C-13 and C-14) of dissolved inorganic carbon and three size-fractions of organic carbon across the Amazonian river system. We find that respiration of contemporary organic matter (less than five years old) originating on land and near rivers is the dominant source of excess carbon dioxide that drives outgassing in medium to large rivers, although we find that bulk organic carbon fractions transported by these rivers range from tens to thousands of years in age. We therefore suggest that a small, rapidly cycling pool of organic carbon is responsible for the large carbon fluxes from land to water to atmosphere in the humid tropics. | |||||
BibTeX:
@article{mayorga_young_2005, author = {Mayorga, E. and Aufdenkampe, A. K. and Masiello, C. A. and Krusche, A. V. and Hedges, J. I. and Quay, P. D. and Richey, J. E. and Brown, T. A.}, title = {Young organic matter as a source of carbon dioxide outgassing from Amazonian rivers}, journal = {Nature}, year = {2005}, volume = {436}, number = {7050}, pages = {538--541}, note = {Edition: 2005/07/29}, url = {://WOS:000230788800057}, doi = {https://doi.org/10.1038/nature03880} } |
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Maurice-Bourgoin, L., Quiroga, I., Chincheros, J. and Courau, P. | Mercury distribution in waters and fishes of the upper Madeira rivers and mercury exposure in riparian Amazonian populations | 2000 | Science of the Total Environment Vol. 260(1-3), pp. 73-86 |
article | DOI URL |
Abstract: In this paper, the results of mercury concentrations in two abiotic compartments (river water and suspended particles) and two biotic compartments (fish and human hair) from the upper Madeira rivers of the Bolivian Amazon basin are presented. Because of the local hydrological regimes and a high deposition rate in the plain, due to the presence of a subsidence zone at the bottom of the Andean piedmont, in the dry season, the highest mercury concentrations and fluxes were not found in rivers where mining activities took place (2.25-6.99 ng l(-1); and 1.07-8.67 mg Hg d(-1) km(-2)), but at the outlet of the Andean basins exploited for their alluvial gold (7.22-8.22 ng l(-1); and 9.47-9.52 mg Hg d(-1) km(-2)). The total mercury concentrations measured in surface waters of the upper Beni basin varied during the dry season, from 2.24 to 2.57 ng l(-1) in the glacial waters of the Zongo river, to 7.00 ng l(-1) in the Madeira River at Porto Velho and 9.49-10.86 ng l(-1) at its confluence with the Amazon. The results obtained from fish indicate, on one hand, that 86% of the piscivorous fishes collected in the Beni river were contaminated, and, on the other hand, their high mercury concentrations could exceed by almost four times the WHO (1976) safety limit. In the Beni River, the mercury concentrations found in omnivorous and mud-feeding fish ranged from 0.02 to 0.19 mu g g(-1) (wet wt.), and in piscivorous fish, from 0.33 to 2.30 mu g Hg g(-1) (wet wt.). The mercury accumulated by carnivorous fishes was mainly present in its organic form; methylmercury represented 73-98% of the total mercury analysed. Eighty persons were studied in the entire Bolivian Amazonian basin. Unlike the gold miners, who are more affected by tropical diseases, such as malaria and yellow fever, the indigenous people living on the banks of the Beni river, present elevated levels of mercury(9.81 mu g g(-1) on average). We observed an increase in contamination in youngs children still being breast-fed, confirming that hair mercury concentration in babies was significantly affected by maternal mercury contamination during pregnancy. These results show that the major health impacts caused by mercury affect people who are not working directly in gold mining activities but who have a regular fish diet. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{maurice-bourgoin_mercury_2000, author = {Maurice-Bourgoin, L. and Quiroga, I. and Chincheros, J. and Courau, P.}, title = {Mercury distribution in waters and fishes of the upper Madeira rivers and mercury exposure in riparian Amazonian populations}, journal = {Science of the Total Environment}, year = {2000}, volume = {260}, number = {1-3}, pages = {73--86}, note = {Edition: 2000/10/14}, url = {://WOS:000089587000007}, doi = {https://doi.org/10.1016/s0048-9697(00)00542-8} } |
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Matricardi, E.A.T., Skole, D.L., Pedlowski, M.A., Chomentowski, W. and Fernandes, L.C. | Assessment of tropical forest degradation by selective logging and fire using Landsat imagery | 2010 | Remote Sensing of Environment Vol. 114(5), pp. 1117-1129 |
article | DOI URL |
Abstract: Many studies have assessed the process of forest degradation in the Brazilian Amazon using remote sensing approaches to estimate the extent and impact by selective logging and forest fires on tropical rain forest. However, only a few have estimated the combined impacts of those anthropogenic activities. We conducted a detailed analysis of selective logging and forest fire impacts on natural forests in the southern Brazilian Amazon state of Mato Grosso, one of the key logging centers in the country. To achieve this goal a 13-year series of annual Landsat images (1992-2004) was used to test different remote sensing techniques for measuring the extent of selective logging and forest fires, and to estimate their impact and interaction with other land use types occurring in the study region. Forest canopy regeneration following these disturbances was also assessed. Field measurements and visual observations were conducted to validate remote sensing techniques. Our results indicated that the Modified Soil Adjusted Vegetation Index aerosol free (MSAVI(af)) is a reliable estimator of fractional coverage under both clear sky and under smoky conditions in this study region. During the period of analysis, selective logging was responsible for disturbing the largest proportion (31%) of natural forest in the study area, immediately followed by deforestation (29%). Altogether, forest disturbances by selective logging and forest fires affected approximately 40% of the study site area. Once disturbed by selective logging activities, forests became more susceptible to fire in the study site. However, our results showed that fires may also occur in undisturbed forests. This indicates that there are further factors that may increase forest fire susceptibility in the study area. Those factors need to be better understood. Although selective logging affected the largest amount of natural forest in the study period, 35% and 28% of the observed losses of forest canopy cover were due to forest fire and selective logging combined and to forest fire only, respectively. Moreover, forest areas degraded by selective logging and forest fire is an addition to outright deforestation estimates and has yet to be accounted for by land use and land cover change assessments in tropical regions. Assuming that this observed trend of land use and land cover conversion continues, we predict that there will be no undisturbed forests remaining by 2011 in this study site. Finally, we estimated that 70% of the total forest area disturbed by logging and fire had sufficiently recovered to become undetectable using satellite data in 2004. (C) 2010 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{matricardi_assessment_2010, author = {Matricardi, Eraldo A. T. and Skole, David L. and Pedlowski, Marcos A. and Chomentowski, Walter and Fernandes, Luis Claudio}, title = {Assessment of tropical forest degradation by selective logging and fire using Landsat imagery}, journal = {Remote Sensing of Environment}, year = {2010}, volume = {114}, number = {5}, pages = {1117--1129}, url = {://WOS:000275780800017}, doi = {https://doi.org/10.1016/j.rse.2010.01.001} } |
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Matricardi, E.A.T., Skole, D.L., Cochrane, M.A., Qi, J. and Chomentowski, W. | Monitoring selective logging in tropical evergreen forests using landsat: Multitemporal regional analyses in Mato Grosso, Brazil | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Selective logging degrades tropical forests. Logging operations vary in timing, location, and intensity. Evidence of this land use is rapidly obscured by forest regeneration and ongoing deforestation. A detailed study of selective logging operations was conducted near Sinop, State of Mato Grosso, Brazil, one of the key Amazonian logging centers. An 11-yr series of annual Lansdat images ( 1992 - 2002) was used to detect and track logged forests across the landscape. A semiautomated method was applied and compared to both visual interpretation and field data. Although visual detection provided precise delineation of some logged areas, it missed many areas. The semiautomated technique provided the best estimates of logging extent that are largely independent of potential user bias. Multitemporal analyses allowed the authors to analyze the annual variations in logging and deforestation, as well as the interaction between them. It is shown that, because of both rapid regrowth and deforestation, evidence of logging activities often disappeared within 1-3 yr. During the 1992 - 2002 interval, a total of 11 449 km(2) of forest was selectively logged. Around 17% of these logged forests had been deforested by 2002. An intra-annual analysis was also conducted using four images spread over a single year. Nearly 3% of logged forests were rapidly deforested during the year in which logging occurred, indicating that even annual monitoring will underestimate logging extent. Great care will need to be taken when inferring logging rates from observations greater than a year apart because of the partial detection of previous years of logging activity. | |||||
BibTeX:
@article{matricardi_monitoring_2005, author = {Matricardi, Eraldo A. T. and Skole, David L. and Cochrane, Mark A. and Qi, Jiaguo and Chomentowski, Walter}, title = {Monitoring selective logging in tropical evergreen forests using landsat: Multitemporal regional analyses in Mato Grosso, Brazil}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241358200001} } |
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Matricardi, E.A.T., Skole, D.L., Cochrane, M.A., Pedlowski, M. and Chomentowski, W. | Multi-temporal assessment of selective logging in the Brazilian Amazon using Landsat data | 2007 | International Journal of Remote Sensing Vol. 28(1-2), pp. 63-82 |
article | DOI URL |
Abstract: Large-scale selective logging is a relatively new activity in the Amazon and its full consequences have yet to be evaluated. Impacts by selective logging alone have been estimated to increase approximately 4-7% of the annual carbon release from deforestation. In this research, visual interpretation and semi-automated remote sensing techniques were applied to identify and map areas of selective logging in tropical terra firme (upland) forests together with the correlated multi-annual measurement results for 1992, 1996, and 1999, for the Brazilian Amazon. The research results indicate that selective logging is rapidly increasing in both intensity (regional) and area (basin-wide). By 1992, at least 5980 km(2) of forest had been logged. During the 1992-1996 and 1996-1999 periods the area impacted expanded by an additional 10 064 km(2), and 26 085 km(2), respectively. Selective logging within protected areas increased more than twofold between 1992 and 1996, and more than fivefold between 1996 and 1999 in that region. We also estimated that at least 3689 km2 had been actively logged in 1992, an additional 5107 km(2), and 11638 km(2), had been logged in 1996 and 1999, and at least 10% of total logged forests detected in 1999 were previously logged in the period of analysis. | |||||
BibTeX:
@article{matricardi_multi-temporal_2007, author = {Matricardi, E. A. T. and Skole, D. L. and Cochrane, M. A. and Pedlowski, M. and Chomentowski, W.}, title = {Multi-temporal assessment of selective logging in the Brazilian Amazon using Landsat data}, journal = {International Journal of Remote Sensing}, year = {2007}, volume = {28}, number = {1-2}, pages = {63--82}, url = {://WOS:000244093200006}, doi = {https://doi.org/10.1080/01431160600763014} } |
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Matias, A.C.C., Lages, A.d.S., Ferreira, P.R.G., Albuquerque, S.D.d., Abreu, A.C.d., Miranda, S.Á.F., Ferreira, S.J.F. and da Silva, M.L. | Bactérias consumidoras de fosfato em uma bacia hidrográfica urbana no centro da Amazônia | 1 | Brazilian Journal of Development Vol. 9(1), pp. 5077-5092 |
article | DOI URL |
Abstract: <p>As preocupações mais difundidas com relação à contaminação por dejetos humanos e animais são causadas por patógenos relacionados a doenças transmitidas pela água e concentrações excessivas de nitrogênio e fósforo que provocam o fenômeno da eutrofização. Dessa forma, esse estudo teve por objetivo avaliar a interação entre a bactéria <em>E. Coli </em>com os teores de fosfato em uma bacia hidrográfica urbana em Manaus. Foram realizadas 14 coletas quinzenais entre os meses de setembro de 2021 e março de 2022. As amostras de água para análise de <em>E. coli </em>foram coletadas próximos da superfície em frascos de vidro de 100 mL, enquanto que para as análises de fosfato, as amostras foram coletadas em frascos de polietileno e acondicionadas até as análises por Colilert e espectrofotometria, respectivamente. Os resultados mostraram que as águas naturalmente ácidas de Manaus apresentaram valores de pH básicos em muitos locais (até 7,20) e que existe uma tendência linear entre fosfato e <em>E. coli</em>. Esse microrganismo prevaleceu em ambientes menos ácidos. Em valores de pH próximos a 7,0 a concentração de fosfato praticamente não muda, como se esse íon estivesse associado a algum tampão no meio (a partir de 0,04 mg L<sup>-1</sup>). A <em>E. coli </em>predominou em todos os pontos cujas concentrações de fosfato foram acima de 0,04 mg L<sup>-1</sup>, obedecendo uma tendência logarítmica típica para crescimento de microbiano. Ao contrário do que se esperava, não houve diluição em direção às fozes desta bacia hidrográfica, nem para fosfato e nem para a <em>E. coli</em>.</p> | |||||
BibTeX:
@article{matias_bacterias_1, author = {Matias, Angélica Chrystina Cruz and Lages, Anderson da Silva and Ferreira, Paulo Renan Gomes and Albuquerque, Samia Dourado de and Abreu, Aretusa Cetauro de and Miranda, Sebastião Átila Fonseca and Ferreira, Sávio José Filgueiras and da Silva, Márcio Luiz}, title = {Bactérias consumidoras de fosfato em uma bacia hidrográfica urbana no centro da Amazônia}, journal = {Brazilian Journal of Development}, year = {1}, volume = {9}, number = {1}, pages = {5077--5092}, note = {Section: Original Papers}, url = {https://ojs.brazilianjournals.com.br/ojs/index.php/BRJD/article/view/56725}, doi = {https://doi.org/10.34117/bjdv9n1-347} } |
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Mateus, P., Borma, L.S., Silva, R.D.d., Nico, G. and Catalão, J. | Assessment of two techniques to merge ground-based and TRMM rainfall measurements: a case study about Brazilian Amazon Rainforest [BibTeX] |
2016 | GIScience & Remote Sensing Vol. 53(6) |
article | DOI |
BibTeX:
@article{mateus_assessment_2016, author = {Mateus, Pedro and Borma, Laura S. and Silva, Ricardo D. da and Nico, Giovanni and Catalão, João}, title = {Assessment of two techniques to merge ground-based and TRMM rainfall measurements: a case study about Brazilian Amazon Rainforest}, journal = {GIScience & Remote Sensing}, year = {2016}, volume = {53}, number = {6}, doi = {https://doi.org/10.1080/15481603.2016.1228161} } |
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Maslin, M., Malhi, Y., Phillips, O. and Cowling, S. | New views on an old forest: assessing the longevity, resilience and future of the Amazon rainforest | 2005 | Transactions of the Institute of British Geographers Vol. 30(4), pp. 477-499 |
article | DOI URL |
Abstract: The aim of this paper is to investigate the longevity and diversity of the Amazonian rainforest and to assess its likely future. Palaeoclimate and palaeoecological records suggest that the Amazon rainforest originated in the late Cretaceous and has been a permanent feature of South America for at least the last 55 million years. The Amazon rainforest has survived the high temperatures of the Early Eocene climate optimum, the gradual Cenozoic cooling, and the drier and lower carbon dioxide levels of the Quaternary glacial periods. Two new theories for the great diversity of the Amazon rainforest are discussed - the canopy density hypothesis and the precessional-forced seasonality hypothesis. We suggest the Amazon rainforest should not be viewed as a geologically ephemeral feature of South America, but rather as a constant feature of the global Cenozoic biosphere. The forest is now, however, entering a set of climatic conditions with no past analogue. The predicted future hotter and more and tropical climates may have a disastrous effect on the Amazon rainforest. | |||||
BibTeX:
@article{maslin_new_2005, author = {Maslin, M. and Malhi, Y. and Phillips, O. and Cowling, S.}, title = {New views on an old forest: assessing the longevity, resilience and future of the Amazon rainforest}, journal = {Transactions of the Institute of British Geographers}, year = {2005}, volume = {30}, number = {4}, pages = {477--499}, url = {://WOS:000234430500008}, doi = {https://doi.org/10.1111/j.1475-5661.2005.00181.x} } |
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Martins, V., Marshak, A., Remer, L., Rosenfeld, D., Kaufman, Y.J., Fernandez-Borda, R., Koren, I., Zubko, V. and Artaxo, P. | Remote sensing the vertical profile of cloud droplet effective radius, thermodynamic phase, and temperature [BibTeX] |
2011 | Atmospheric Chemistry and Physics Vol. 11, pp. 9485-9501 |
article | DOI |
BibTeX:
@article{martins_remote_2011, author = {Martins, V.J. and Marshak, A. and Remer, L. and Rosenfeld, D. and Kaufman, Y. J. and Fernandez-Borda, R. and Koren, I. and Zubko, V. and Artaxo, P.}, title = {Remote sensing the vertical profile of cloud droplet effective radius, thermodynamic phase, and temperature}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, pages = {9485--9501}, doi = {https://doi.org/10.5194/acp-11-9485-2011} } |
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Martins, R.C.G., Machado, L.A.T. and Costa, A.A. | Characterization of the microphysics of precipitation over Amazon region using radar and disdrometer data | 2010 | Atmospheric Research Vol. 96(2-3), pp. 388-394 |
article | DOI URL |
Abstract: This work presents a characterization of the Amazonian precipitation diurnal cycle through an analysis of radar reflectivity profiles and drop-size distributions attained respectively from a microwave vertical profiler and a disdrometer during the 1999 WET-AMC experiment. In such analysis, precipitation was split in time and classes, which provided information on the daily variation of typical reflectivity profiles and the raindrop spectra associated with them. A clear signature of the diurnal cycle can be observed in the radar profiles and in the raindrop size distribution; for instance, the stratiform rainfall is dominant in the period of 03: 00 to 09: 00 LST showing the collapse of the convective structures dominant during the afternoon. The time interval centered at 21: 00 LST shows the collapse of the ice phase and convective activity, typical of the transition from convective to stratiform precipitation. The size distribution and the reflectivity profiles also depend on the rainfall intensity. The combined analysis of the diurnal cycle and rainfall intensity shows interesting features of the cloud life cycle over the Amazon region, including the initiation of ice and the establishment of the bright band. Statistical analysis revealed that most RDSDs exhibit a single peak around 0.5 mm (48.9%), 1.0 mm (30.7%) or 2.0 mm (2.5%) and that only a few are effectively bimodal, which permitted the use of gamma distributions to fit most of the observed raindrop spectra. (c) 2010 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{martins_characterization_2010, author = {Martins, Rafael C. G. and Machado, Luiz A. T. and Costa, Alexandre A.}, title = {Characterization of the microphysics of precipitation over Amazon region using radar and disdrometer data}, journal = {Atmospheric Research}, year = {2010}, volume = {96}, number = {2-3}, pages = {388--394}, url = {://WOS:000281880200019}, doi = {https://doi.org/10.1016/j.atmosres.2010.01.011} } |
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Martins, N.P., Fuchslueger, L., Fleischer, K., Andersen, K.M., Assis, R.L., Baccaro, F.B., Camargo, P.B., Cordeiro, A.L., Grandis, A., Hartley, I.P., Hofhansl, F., Lugli, L.F., Lapola, D.M., Menezes, J.G., Norby, R.J., Rammig, A., Rosa, J.S., Schaap, K.J., Takeshi, B., Valverde-Barrantes, O.J. and Quesada, C.A. | Fine roots stimulate nutrient release during early stages of leaf litter decomposition in a Central Amazon rainforest | 2021 | Plant and Soil Vol. 469(1), pp. 287-303 |
article | DOI URL |
Abstract: Large parts of the Amazon rainforest grow on weathered soils depleted in phosphorus and rock-derived cations. We tested the hypothesis that in this ecosystem, fine roots stimulate decomposition and nutrient release from leaf litter biochemically by releasing enzymes, and by exuding labile carbon stimulating microbial decomposers. | |||||
BibTeX:
@article{martins_fine_2021, author = {Martins, Nathielly P. and Fuchslueger, Lucia and Fleischer, Katrin and Andersen, Kelly M. and Assis, Rafael L. and Baccaro, Fabricio B. and Camargo, Plínio B. and Cordeiro, Amanda L. and Grandis, Adriana and Hartley, Iain P. and Hofhansl, Florian and Lugli, Laynara F. and Lapola, David M. and Menezes, Juliane G. and Norby, Richard J. and Rammig, Anja and Rosa, Jessica S. and Schaap, Karst J. and Takeshi, Bruno and Valverde-Barrantes, Oscar J. and Quesada, Carlos A.}, title = {Fine roots stimulate nutrient release during early stages of leaf litter decomposition in a Central Amazon rainforest}, journal = {Plant and Soil}, year = {2021}, volume = {469}, number = {1}, pages = {287--303}, url = {https://doi.org/10.1007/s11104-021-05148-9}, doi = {https://doi.org/10.1007/s11104-021-05148-9} } |
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Martins, J.V., Artaxo, P., Kaufman, Y.J., Castanho, A.D. and Remer, L.A. | Spectral absorption properties of aerosol particles from 350-2500nm | 2009 | Geophysical Research Letters Vol. 36(13), pp. L13810 |
article | DOI URL |
Abstract: The aerosol spectral absorption efficiency (alpha(a) in m(2)/g) is measured over an extended wavelength range (350-2500 nm) using an improved calibrated and validated reflectance technique and applied to urban aerosol samples from Sao Paulo, Brazil and from a site in Virginia, Eastern US, that experiences transported urban/industrial aerosol. The average alpha(a) values (similar to 3m(2)/g at 550 nm) for Sao Paulo samples are 10 times larger than a a values obtained for aerosols in Virginia. Sao Paulo aerosols also show evidence of enhanced UV absorption in selected samples, probably associated with organic aerosol components. This extra UV absorption can double the absorption efficiency observed from black carbon alone, therefore reducing by up to 50% the surface UV fluxes, with important implications for climate, UV photolysis rates, and remote sensing from space. Citation: Martins, J.V., P. Artaxo, Y.J. Kaufman, A.D. Castanho, and L.A. Remer (2009), Spectral absorption properties of aerosol particles from 350-2500nm, Geophys. Res. Lett., 36, L13810, doi: 10.1029/2009GL037435. | |||||
BibTeX:
@article{martins_spectral_2009, author = {Martins, J. Vanderlei and Artaxo, Paulo and Kaufman, Yoram J. and Castanho, Andrea D. and Remer, Lorraine A.}, title = {Spectral absorption properties of aerosol particles from 350-2500nm}, journal = {Geophysical Research Letters}, year = {2009}, volume = {36}, number = {13}, pages = {L13810}, url = {://WOS:000270289300001}, doi = {https://doi.org/10.1029/2009gl037435} } |
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Martins, J.A. and Silva Dias, M.A.F. | The impact of smoke from forest fires on the spectral dispersion of cloud droplet size distributions in the Amazonian region | 2009 | Environmental Research Letters Vol. 4(1) |
article | DOI URL |
Abstract: In this paper, the main microphysical characteristics of clouds developing in polluted and clean conditions in the biomass-burning season of the Amazon region are examined, with special attention to the spectral dispersion of the cloud droplet size distribution and its potential impact on climate modeling applications. The dispersion effect has been shown to alter the climate cooling predicted by the so-called Twomey effect. In biomass-burning polluted conditions, high concentrations of low dispersed cloud droplets are found. Clean conditions revealed an opposite situation. The liquid water content (0.43 +/- 0.19 g m(-3)) is shown to be uncorrelated with the cloud drop number concentration, while the effective radius is found to be very much correlated with the relative dispersion of the size distribution (R(2) = 0.81). The results suggest that an increase in cloud condensation nuclei concentration from biomass-burning aerosols may lead to an additional effect caused by a decrease in relative dispersion. Since the dry season in the Amazonian region is vapor limiting, the dispersion effect of cloud droplet size distributions could be substantially larger than in other polluted regions. | |||||
BibTeX:
@article{martins_impact_2009, author = {Martins, J. A. and Silva Dias, M. A. F.}, title = {The impact of smoke from forest fires on the spectral dispersion of cloud droplet size distributions in the Amazonian region}, journal = {Environmental Research Letters}, year = {2009}, volume = {4}, number = {1}, url = {://WOS:000265878500016}, doi = {https://doi.org/10.1088/1748-9326/4/1/015002} } |
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Martins, J.A., Goncalves, F.L.T., Morales, C.A., Fisch, G.F., Pinheiro, F.G.M., Leal Jr., J.B.V., Oliveira, C.J., Silva, E.M., Oliveira, J.C.P., Costa, A.A. and Silva Dias, M.A.F. | Cloud condensation nuclei from biomass burning during the Amazonian dry-to-wet transition season | 2009 | Meteorology and Atmospheric Physics Vol. 104(1-2), pp. 83-93 |
article | DOI URL |
Abstract: Aircraft measurements of cloud condensation nuclei (CCN) during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) were conducted over the Southwestern Amazon region in September-October 2002, to emphasize the dry-to-wet transition season. The CCN concentrations were measured for values within the range 0.1-1.0% of supersaturation. The CCN concentration inside the boundary layer revealed a general decreasing trend during the transition from the end of the dry season to the onset of the wet season. Clean and polluted areas showed large differences. The differences were not so strong at high levels in the troposphere and there was evidence supporting the semi-direct aerosol effect in suppressing convection through the evaporation of clouds by aerosol absorption. The measurements also showed a diurnal cycle following biomass burning activity. Although biomass burning was the most important source of CCN, it was seen as a source of relatively efficient CCN, since the increase was significant only at high supersaturations. | |||||
BibTeX:
@article{martins_cloud_2009, author = {Martins, Jorge Alberto and Goncalves, Fabio Luiz T. and Morales, Carlos A. and Fisch, Gilberto F. and Pinheiro, Francisco Geraldo M. and Leal, Jr., Joao Bosco V. and Oliveira, Carlos J. and Silva, Emerson M. and Oliveira, Jose Carlos P. and Costa, Alexandre A. and Silva Dias, Maria Assuncao F.}, title = {Cloud condensation nuclei from biomass burning during the Amazonian dry-to-wet transition season}, journal = {Meteorology and Atmospheric Physics}, year = {2009}, volume = {104}, number = {1-2}, pages = {83--93}, url = {://WOS:000265919400007 http://www.springerlink.com/content/r9711503h1275625/fulltext.pdf}, doi = {https://doi.org/10.1007/s00703-009-0019-6} } |
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Martins, J.A., Dias, M.A.F.S. and Goncalves, F.L.T. | Impact of biomass burning aerosols on precipitation in the Amazon: A modeling case study | 2009 | Journal of Geophysical Research-Atmospheres Vol. 114 |
article | DOI URL |
Abstract: A study of the potential role of aerosols in modifying clouds and precipitation is presented using a numerical atmospheric model. Measurements of cloud condensation nuclei (CCN) and cloud size distribution properties taken in the southwestern Amazon region during the transition from dry to wet seasons were used as guidelines to define the microphysical parameters for the simulations. Numerical simulations were carried out using the Brazilian Development on Regional Atmospheric Modeling System, and the results presented considerable sensitivity to changes in these parameters. High CCN concentrations, typical of polluted days, were found to result in increases or decreases in total precipitation, depending on the level of pollution used as a reference, showing a complexity that parallels the aerosol-precipitation interaction. Our results show that on the grids evaluated, higher CCN concentrations reduced low-to-moderate rainfall rates and increased high rainfall rates. The principal consequence of the increased pollution was a change from a warm to a cold rain process, which affected the maximum and overall mean accumulated precipitation. Under polluted conditions, cloud cover diminished, allowing greater amounts of solar radiation to reach the surface. Aerosol absorption of radiation in the lower layers of the atmosphere delayed convective evolution but produced higher maximum rainfall rates due to increased instability. In addition, the intensity of the surface sensible heat flux, as well as that of the latent heat flux, was reduced by the lower temperature difference between surface and air, producing greater energy stores at the surface. | |||||
BibTeX:
@article{martins_impact_2009-1, author = {Martins, J. A. and Dias, M. A. F. Silva and Goncalves, F. L. T.}, title = {Impact of biomass burning aerosols on precipitation in the Amazon: A modeling case study}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2009}, volume = {114}, url = {://WOS:000262982400001}, doi = {https://doi.org/10.1029/2007jd009587} } |
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Martins, D.L., Schietti, J., Feldpausch, T.R., Luizão, F.J., Phillips, O.L., Andrade, A., Castilho, C.V., Laurance, S.G., Oliveira, Á., Amaral, I.L., Toledo, J.J., Lugli, L.F., Veiga Pinto, J.L.P., Mendoza, E.M.O. and Quesada, C.A. | Soil-induced impacts on forest structure drive coarse woody debris stocks across central Amazonia [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 1-13 |
article | |
BibTeX:
@article{martins_soil-induced_2014, author = {Martins, Demétrius L. and Schietti, Juliana and Feldpausch, Ted R. and Luizão, Flávio J. and Phillips, Oliver L. and Andrade, Ana and Castilho, Carolina V. and Laurance, Susan G. and Oliveira, Átila and Amaral, Ieda L. and Toledo, José J. and Lugli, Laynara F. and Veiga Pinto, José Luiz Purri and Mendoza, Erick M. Oblitas and Quesada, Carlos A.}, title = {Soil-induced impacts on forest structure drive coarse woody debris stocks across central Amazonia}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {1--13} } |
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Martinez, I.S., Peterson, M.D., Ebben, C.J., Hayes, P.L., Artaxo, P., Martin, S.T. and Geiger, F.M. | On molecular chirality within naturally occurring secondary organic aerosol particles from the central Amazon Basin | 2011 | Physical Chemistry Chemical Physics Vol. 13(26), pp. 12114-12122 |
article | DOI URL |
Abstract: In this perspectives article, we reflect upon the existence of chirality in atmospheric aerosol particles. We then show that organic particles collected at a field site in the central Amazon Basin under pristine background conditions during the wet and dry seasons consist of chiral secondary organic material. We show how the chiral response from the aerosol particles can be imaged directly without the need for sample dissolution, solvent extraction, or sample preconcentration. By comparing the chiral-response images with optical images, we show that chiral responses always originate from particles on the filter, but not all aerosol particles produce chiral signals. The intensity of the chiral signal produced by the size resolved particles strongly indicates the presence of chiral secondary organic material in the particle. Finally, we discuss the implications of our findings on chiral atmospheric aerosol particles in terms of climate-related properties and source apportionment. | |||||
BibTeX:
@article{martinez_molecular_2011, author = {Martinez, Imee Su and Peterson, Mark D. and Ebben, Carlena J. and Hayes, Patrick L. and Artaxo, Paulo and Martin, Scot T. and Geiger, Franz M.}, title = {On molecular chirality within naturally occurring secondary organic aerosol particles from the central Amazon Basin}, journal = {Physical Chemistry Chemical Physics}, year = {2011}, volume = {13}, number = {26}, pages = {12114--12122}, note = {Edition: 2011/06/03}, url = {://WOS:000291885300001}, doi = {https://doi.org/10.1039/c1cp20428a} } |
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Martinelli, L.A., Victoria, R.L., de Camargo, P.B., Piccolo, M.D., Mertes, L., Richey, J.E., Devol, A.H. and Forsberg, B.R. | Inland variability of carbon-nitrogen concentrations and delta C-13 in Amazon floodplain (varzea) vegetation and sediment | 2003 | Hydrological Processes Vol. 17(7), pp. 1419-1430 |
article | DOI URL |
Abstract: We analysed carbon, nitrogen and delta(13)C values in sediment sampled in the Amazon floodplains. The surface sediment samples were collected along inland transects divided according to their vegetation cover: (a) forest, where the dominant vegetation was inundation forests; (b) grass, where the dominant vegetation was grasses, mainly from Echnochloa polystachya; (c) mixed, where the vegetation changed from grasses near the river bank to forest inland. The average sediment carbon and nitrogen concentrations were significantly higher in forest samples (C = 0.99%, N = 0.12%) than in grass samples (C = 0.84%, N = 0.10%). The average sediment delta(13)C was significantly heavier in grass (-26.7parts per thousand) than in forest samples (-28.6parts per thousand), reflecting the isotopically heavier C-4 grasses carbon. In the forest and mixed transects inland, increases in the carbon and nitrogen concentrations were observed. At approximately 50 to 60 m from the riverbank, the concentration of carbon and nitrogen became similar to the river particulate organic carbon (POC) concentration, which is the primary floodplain sediment source. We hypothesized that this trend is caused by the deposition of carbon- and nitrogen-depleted sand-size particles in the first few metres of the floodplain, whereas the more enriched silt-clay particles are preferentially deposited far inland. In contrast to inland trends, no significant downriver trend was observed in the carbon and nitrogen concentrations. However, a downriver delta(13)C increase was observed for sediment in grass-covered areas. Based on delta(13)C values in different varzea environments, we estimated the relative contribution of riverine POC and vegetation material present in the varzea sediments under different vegetation covers. For forest sediment samples we estimated that 60% of the carbon was derived from the riverine POC and the forests provided the remaining 40%. For open areas covered with grasses we estimated that only 10% was derived from these plants, and 90% was derived from riverine POC. Copyright (C) 2003 John Wiley Sons, Ltd. | |||||
BibTeX:
@article{martinelli_inland_2003, author = {Martinelli, L. A. and Victoria, R. L. and de Camargo, P. B. and Piccolo, M. D. and Mertes, L. and Richey, J. E. and Devol, A. H. and Forsberg, B. R.}, title = {Inland variability of carbon-nitrogen concentrations and delta C-13 in Amazon floodplain (varzea) vegetation and sediment}, journal = {Hydrological Processes}, year = {2003}, volume = {17}, number = {7}, pages = {1419--1430}, url = {://WOS:000182601000012}, doi = {https://doi.org/10.1002/hyp.1293} } |
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Martinelli, L.A., Camargo, P., Lara, L., Victoria, R. and Artaxo, P. | Stable carbon and nitrogen isotopic composition of bulk aerosol particles in a C4 plant landscape of southeast Brazil [BibTeX] |
2002 | Atmospheric Environment Vol. 36, pp. 2427-2432 |
article | |
BibTeX:
@article{martinelli_stable_2002, author = {Martinelli, L. A. and Camargo, P.B. and Lara, L.B.L.S. and Victoria, R.L. and Artaxo, P.}, title = {Stable carbon and nitrogen isotopic composition of bulk aerosol particles in a C4 plant landscape of southeast Brazil}, journal = {Atmospheric Environment}, year = {2002}, volume = {36}, pages = {2427--2432} } |
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Martinelli, L.A., Almeida, S., Brown, I.F., Moreira, M.Z., Victoria, R.L., Sternberg, L.S.L., Ferreira, C.A.C. and Thomas, W.W. | Stable carbon isotope ratio of tree leaves, boles and fine litter in a tropical forest in Rondonia, Brazil | 1998 | Oecologia Vol. 114(2), pp. 170-179 |
article | DOI URL |
Abstract: Leaves of 208 trees were collected for isotopic analysis together with wood from 36 tree boles and 18 samples of fine litter from a terra-firme forest located at Samuel Ecological Reserve, Rondonia State, in the southwestern Amazon region. The range of delta(13)C values in leaves was from -28 to -36 parts per thousand, with an average (+/-1 SD) of -32.1 +/- 1.5 parts per thousand, which was more negative than the delta(13)C values Of bole samples (-28.4 +/- 2.0 parts per thousand) and fine litter (-28.7 +/- 2.0 parts per thousand). These values are within the range found for tropical and subtropical forests. Pooling the delta(13)C values for leaf samples from trees of the same height gave averages which were positively correlated with plant height at a highly significant level, with a slope of 0.06 and an intercept of -33.3 parts per thousand and a correlation coefficient r(2) = 0.70 (P textless 0.001). | |||||
BibTeX:
@article{martinelli_stable_1998, author = {Martinelli, L. A. and Almeida, S. and Brown, I. F. and Moreira, M. Z. and Victoria, R. L. and Sternberg, L. S. L. and Ferreira, C. A. C. and Thomas, W. W.}, title = {Stable carbon isotope ratio of tree leaves, boles and fine litter in a tropical forest in Rondonia, Brazil}, journal = {Oecologia}, year = {1998}, volume = {114}, number = {2}, pages = {170--179}, note = {Edition: 1972/11/01}, url = {://WOS:000073019100004}, doi = {https://doi.org/10.1007/s004420050433} } |
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Martinelli, L.A., Almeida, S., Brown, I.F., Moreira, M.Z., Victoria, R.L., Filoso, S., Ferreira, C.A.C. and Thomas, W.W. | Variation in nutrient distribution and potential nutrient losses by selective logging in a humid tropical forest of Rondonia, Brazil | 2000 | Biotropica Vol. 32(4), pp. 597-613 |
article | DOI URL |
Abstract: Despite having one of the world's highest deforestation rates, the tropical forest of Rondonia state in the southwest Amazon is virtually unknown in terms of nutrient dynamics. To fill this knowledge gap, the distribution of nutrients in a humid tropical forest located in the Ecological Reserve of Samuel, Rondonia state, was addressed. A total of 474 trees with diameter at breast height (DBH) textgreater 10 cm were mapped at the Ecological Reserve of Samuel, a 20,000-ha area bordering the Samuel Hydroelectric Reservoir, which is located 50 km south of Porto Velho, Rondonia state, Amazon region, Brazil. These individuals belonged to ca 220 species distributed in 41 families. From this total, leaves of 354 trees were collected for chemical compositional analysis; boles of 96 trees and fine branches of 75 trees also were collected. Soil samples were gathered for fertility analysis at two soil depth intervals: 0-50 and 50-100 cm. In general, soils were acidic and very poor in terms of elemental contents. For plants, the highest concentrations of P, K, and Mg were found in leaves and fine branches, and the highest concentration of Ca was in the litter. The lowest nutrient concentration was observed in boles. The nutrient concentrations of leaves collected at Samuel were similar to that found in other terra firme forests of the Amazon region and other tropical forests growing on poor soils. Comparisons of nutrient concentrations among families, genera, and species revealed that only N concentrations were distinct among botanical taxa; the variability found in concentrations of other nutrient were larger and did not reveal any significant differences. Like aboveground biomass, the total nutrient stocks of trees was concentrated in a few large individuals. This fact reveals important implications about the impacts caused by selective logging. Although few trees are cut per hectare in this activity, the effects; on the ecosystem structure, due to the loss of nutrients, may be underestimated. | |||||
BibTeX:
@article{martinelli_variation_2000, author = {Martinelli, L. A. and Almeida, S. and Brown, I. F. and Moreira, M. Z. and Victoria, R. L. and Filoso, S. and Ferreira, C. A. C. and Thomas, W. W.}, title = {Variation in nutrient distribution and potential nutrient losses by selective logging in a humid tropical forest of Rondonia, Brazil}, journal = {Biotropica}, year = {2000}, volume = {32}, number = {4}, pages = {597--613}, url = {://WOS:000166540200003}, doi = {https://doi.org/10.1646/0006-3606(2000)032%5B0597:vindap%5D2.0.co;2} } |
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Martin, S., Artaxo, P., Machado, L., Manzi, A.O., Souza, R.A.F., Schumacher, C., Wang, J., Andreae, M., Barbosa, H., Fan, J., Fisch, G., Goldstein, A., Guenther, A., Jimenez, J., Pöschl, U., Silva Dias, M., Smith, J.N. and Wendisch, M. | Introduction: Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 4785-4797 |
article | DOI |
BibTeX:
@article{martin_introduction_2016, author = {Martin, S.T. and Artaxo, P. and Machado, L.A.T. and Manzi, A. O. and Souza, R. A. F. and Schumacher, C. and Wang, J. and Andreae, M.O. and Barbosa, H.M.J. and Fan, J. and Fisch, G. and Goldstein, A.H. and Guenther, A. and Jimenez, J.L. and Pöschl, U. and Silva Dias, M.A. and Smith, J. N. and Wendisch, M.}, title = {Introduction: Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5)}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {4785--4797}, note = {Edition: www.atmos-chem-phys.net/16/4785/2016/}, doi = {https://doi.org/10.5194/acp-16-4785-2016} } |
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Martin, S.T., Artaxo, P., Machado, L., Manzi, A.O., Souza, R.A.F., Schumacher, C., Wang, J., Biscaro, T. and J. Brito K. Jardine, A.M.B.P.S.S.d.S.K.A.A.C.A.R.A.L.A.M.O.A.H.M.J.B.P.B.D.C.J.M.C.D.A.D.M.D.J.F.J.F.G.F.E.F.S.G.M.G.A.H.G.A.G.J.H.M.J.J.L.J.F.N.K.S.K.C.K.A.L.K.M.F.M.M.M.R.N.T.P.M.P.J.P.T.P.C.P.U.P.L.R.B.S.J.E.S.M.A.S.D.J.N.S.J.M.T.J.T.and.M.W.A.C. | The Green Ocean Amazon Experiment (Goamazon2014/5) observes pollution affecting gases, aerosols, clouds, and rainfall over the rain forest [BibTeX] |
2017 | American Meteorological Society | article | DOI |
BibTeX:
@article{martin_green_2017, author = {Martin, S. T. and Artaxo, P. and Machado, L. and Manzi, A. O. and Souza, R. A. F. and Schumacher, C. and Wang, J. and Biscaro, T. and J. Brito, K. Jardine, A. Medeiros, B. Portela, S. S. de Sá, K. Adachi, A. C. Aiken, R. Albrecht, L. Alexander, M. O. Andreae, H. M. J. Barbosa, P. Buseck, D. Chand, J. M. Comstock, D. A. Day, M. Dubey, J. Fan, J. Fast, G. Fisch, E. Fortner, S. Giangrande, M. Gilles, A. H. Goldstein, A. Guenther, J. Hubbe, M. Jensen, J. L. Jimenez, F. N. Keutsch, S. Kim, C. Kuang, A. Laskin, K. McKinney, F. Mei, M. Miller, R. Nascimento, T. Pauliquevis, M. Pekour, J. Peres, T. Petäjä, C. Pöhlker, U. Pöschl, L. Rizzo, B. Schmid, J. E. Shilling, M. A. Silva Dias, J. N. Smith, J. M. Tomlinson, J. Tóta, and M. Wendisch, A. Calheiros}, title = {The Green Ocean Amazon Experiment (Goamazon2014/5) observes pollution affecting gases, aerosols, clouds, and rainfall over the rain forest}, journal = {American Meteorological Society}, year = {2017}, doi = {https://doi.org/10.1175/BAMS-D-15-00221.1} } |
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Martin, S., Andreae, M., Artaxo, P., Baumgardner, D., Chen, Q., Goldstein, A., Guenther, A., Heald, C.L., Mayol-Bracero, O., McMurry, P., Pauliquevis, T., Poeschl, U., Prather, K., Roberts, G., Saleska, S., Silva Dias, M.A., Spracklen, D., Swietlicki, E. and Trebs, I. | Sources and properties of amazonian aerosol particles | 2010 | Reviews of Geophysics Vol. 48 |
article | DOI URL |
Abstract: This review provides a comprehensive account of what is known presently about Amazonian aerosol particles and concludes by formulating outlook and priorities for further research. The review is organized to follow the life cycle of Amazonian aerosol particles. It begins with a discussion of the primary and secondary sources relevant to the Amazonian particle burden, followed by a presentation of the particle properties that characterize the mixed populations present over the Amazon Basin at different times and places. These properties include number and mass concentrations and distributions, chemical composition, hygroscopicity, and cloud nucleation ability. The review presents Amazonian aerosol particles in the context of natural compared to anthropogenic sources as well as variability with season and meteorology. This review is intended to facilitate an understanding of the current state of knowledge on Amazonian aerosol particles specifically and tropical continental aerosol particles in general and thereby to enhance future research in this area. | |||||
BibTeX:
@article{martin_sources_2010, author = {Martin, S.T. and Andreae, M.O. and Artaxo, P. and Baumgardner, D. and Chen, Q. and Goldstein, A.H. and Guenther, A. and Heald, C. L. and Mayol-Bracero, O.L. and McMurry, P.H. and Pauliquevis, T. and Poeschl, U. and Prather, K.A. and Roberts, G.C. and Saleska, S.R. and Silva Dias, M. A. and Spracklen, D.V. and Swietlicki, E. and Trebs, I.}, title = {Sources and properties of amazonian aerosol particles}, journal = {Reviews of Geophysics}, year = {2010}, volume = {48}, url = {://WOS:000276831600001}, doi = {https://doi.org/10.1029/2008rg000280} } |
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Martin, S.T., Andreae, M.O., Althausen, D., Artaxo, P., Baars, H., Borrmann, S., Chen, Q., Farmer, D.K., Guenther, A., Gunthe, S.S., Jimenez, J.L., Karl, T., Longo, K., Manzi, A., Müller, T., Pauliquevis, T., Petters, M.D., Prenni, A.J., Pöschl, U., Rizzo, L.V., Schneider, J., Smith, J.N., Swietlicki, E., Tota, J., Wang, J., Wiedensohler, A. and Zorn, S.R. | An overview of the Amazonian Aerosol Characterization Experiment 2008 (AMAZE-08) | 2010 | Atmospheric Chemistry and Physics Vol. 10(23), pp. 11415-11438 |
article | DOI URL |
Abstract: The Amazon Basin provides an excellent environment for studying the sources, transformations, and properties of natural aerosol particles and the resulting links between biological processes and climate. With this framework in mind, the Amazonian Aerosol Characterization Experiment (AMAZE-08), carried out from 7 February to 14 March 2008 during the wet season in the central Amazon Basin, sought to understand the formation, transformations, and cloud-forming properties of fine-and coarse-mode biogenic aerosol particles, especially as related to their effects on cloud activation and regional climate. Special foci included (1) the production mechanisms of secondary organic components at a pristine continental site, including the factors regulating their temporal variability, and (2) predicting and understanding the cloud-forming properties of biogenic particles at such a site. In this overview paper, the field site and the instrumentation employed during the campaign are introduced. Observations and findings are reported, including the large-scale context for the campaign, especially as provided by satellite observations. New findings presented include: (i) a particle number-diameter distribution from 10 nm to 10 mu m that is representative of the pristine tropical rain forest and recommended for model use; (ii) the absence of substantial quantities of primary biological particles in the submicron mode as evidenced by mass spectral characterization; (iii) the large-scale production of secondary organic material; (iv) insights into the chemical and physical properties of the particles as revealed by thermodenuder-induced changes in the particle number-diameter distributions and mass spectra; and (v) comparisons of ground-based predictions and satellite-based observations of hydrometeor phase in clouds. A main finding of AMAZE-08 is the dominance of secondary organic material as particle components. The results presented here provide mechanistic insight and quantitative parameters that can serve to increase the accuracy of models of the formation, transformations, and cloud-forming properties of biogenic natural aerosol particles, especially as related to their effects on cloud activation and regional climate. | |||||
BibTeX:
@article{martin_overview_2010, author = {Martin, S. T. and Andreae, M. O. and Althausen, D. and Artaxo, P. and Baars, H. and Borrmann, S. and Chen, Q. and Farmer, D. K. and Guenther, A. and Gunthe, S. S. and Jimenez, J. L. and Karl, T. and Longo, K. and Manzi, A. and Müller, T. and Pauliquevis, T. and Petters, M. D. and Prenni, A. J. and Pöschl, U. and Rizzo, L. V. and Schneider, J. and Smith, J. N. and Swietlicki, E. and Tota, J. and Wang, J. and Wiedensohler, A. and Zorn, S. R.}, title = {An overview of the Amazonian Aerosol Characterization Experiment 2008 (AMAZE-08)}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {23}, pages = {11415--11438}, url = {://WOS:000285334900007}, doi = {https://doi.org/10.5194/acp-10-11415-2010} } |
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Marthews, C.A., Galbraith, D.R., Malhi, Y., Mullins, C.E., HodnetT, M.G., Dharssi I., T.R. and Quesada | High-resolution hydraulic parameter maps for surface soils in tropical South America [BibTeX] |
2014 | Geoscientific Model Development Vol. 7, pp. 711-723 |
article | |
BibTeX:
@article{marthews_high-resolution_2014, author = {Marthews, C. A. ; Galbraith, D. R. ; Malhi, Y. ; Mullins, C. E. ; HodnetT, M. G. ; Dharssi, I., T. R. ; Quesada}, title = {High-resolution hydraulic parameter maps for surface soils in tropical South America}, journal = {Geoscientific Model Development}, year = {2014}, volume = {7}, pages = {711--723} } |
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Marthews, T., Malhi, Y., Girardin, C., Espejo, J., Aragão, L., Metcalfe, D., Rapp, J., Mercado, L., Fisher, R., Galbraith, D., Fisher, J., Salinas-Revilla, N., Friend, A., Restrepo-Coupe, N. and Williams, R. | Simulating forest productivity along a neotropical elevational transect: temperature variation and carbon use efficiency [BibTeX] |
2012 | Global Change Biology Vol. 18(9), pp. 2882-2898 |
article | DOI |
BibTeX:
@article{marthews_simulating_2012, author = {Marthews, T.R and Malhi, Y. and Girardin, C.A.J. and Espejo, J.E.S. and Aragão, L.E.O.C. and Metcalfe, D.B. and Rapp, J.M. and Mercado, L.M. and Fisher, R.A. and Galbraith, D.R. and Fisher, J.B. and Salinas-Revilla, N. and Friend, A.D. and Restrepo-Coupe, N. and Williams, R.J.}, title = {Simulating forest productivity along a neotropical elevational transect: temperature variation and carbon use efficiency}, journal = {Global Change Biology}, year = {2012}, volume = {18}, number = {9}, pages = {2882--2898}, doi = {https://doi.org/10.1111/j.1365-2486.2012.02728.x} } |
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Martens, C., Shay, T., Mendlovitz, H.P., Matross, D., Saleska, S., Wofsy, S.C., Stephen Woodward, W., Menton, M., De Moura, J.S., Crill, P.M., De Moraes, O.L.L. and Lima, R.L. | Radon fluxes in tropical forest ecosystems of Brazilian Amazonia: night-time CO2 net ecosystem exchange derived from radon and eddy covariance methods | 2004 | Global Change Biology Vol. 10(5), pp. 618-629 |
article | DOI URL |
Abstract: Radon-222 (Rn-222) is used as a transport tracer of forest canopy-atmosphere CO(2) exchange in an old-growth, tropical rain forest site near km 67 of the Tapajos National Forest, Para, Brazil. Initial results, from month-long periods at the end of the wet season (June-July) and the end of the dry season (November-December) in 2001, demonstrate the potential of new Rn measurement instruments and methods to quantify mass transport processes between forest canopies and the atmosphere. Gas exchange rates yield mean canopy air residence times ranging from minutes during turbulent daytime hours to greater than 12 h during calm nights. Rn is an effective tracer for net ecosystem exchange of CO(2) (CO(2) NEE) during calm, night-time hours when eddy covariance-based NEE measurements are less certain because of low atmospheric turbulence. Rn-derived night-time CO(2) NEE (9.00+/-0.99 mumol m(-2) s(-1) in the wet season, 6.39+/-0.59 in the dry season) was significantly higher than raw uncorrected, eddy covariance-derived CO(2) NEE (5.96+/-0.51 wet season, 5.57+/-0.53 dry season), but agrees with corrected eddy covariance results (8.65+/-1.07 wet season, 6.56+/-0.73 dry season) derived by filtering out lower NEE values obtained during calm periods using independent meteorological criteria. The Rn CO(2) results suggest that uncorrected eddy covariance values underestimate night-time CO(2) loss at this site. If generalizable to other sites, these observations indicate that previous reports of strong net CO(2) uptake in Amazonian terra firme forest may be overestimated. | |||||
BibTeX:
@article{martens_radon_2004, author = {Martens, C.S. and Shay, T.J. and Mendlovitz, H. P. and Matross, D.M. and Saleska, S.R. and Wofsy, S. C. and Stephen Woodward, W. and Menton, M.C. and De Moura, J.M. S. and Crill, P. M. and De Moraes, O. L. L. and Lima, R. L.}, title = {Radon fluxes in tropical forest ecosystems of Brazilian Amazonia: night-time CO2 net ecosystem exchange derived from radon and eddy covariance methods}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {618--629}, url = {://WOS:000221421600007}, doi = {https://doi.org/10.1111/j.1365-2486.2004.00764.x} } |
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Marra, D., Higuchi, N., Trumbore, S., Ribeiro, G., Santos, J.d., Carneiro, V., Lima, A., Chambers, J., Negrón-Juárez, R., Holzwarth, F., Reu, B. and Wirth, C. | Predicting biomass of hyperdiverse and structurally complex central Amazonian forests – a virtual approach using extensive field data [BibTeX] |
2016 | Biogeosciences Vol. 13, pp. 1553-1570 |
article | |
BibTeX:
@article{marra_predicting_2016, author = {Marra, D.M. and Higuchi, N. and Trumbore, S.E. and Ribeiro, G.H.P.M. and Santos, J. dos and Carneiro, V.M.C. and Lima, A.J.N. and Chambers, J.Q. and Negrón-Juárez, R.I. and Holzwarth, F. and Reu, B. and Wirth, C.}, title = {Predicting biomass of hyperdiverse and structurally complex central Amazonian forests – a virtual approach using extensive field data}, journal = {Biogeosciences}, year = {2016}, volume = {13}, pages = {1553--1570} } |
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Marques-Filho, A., Dallarosa, R. and Pachêco, V. | Radiação solar e distribuição vertical de área foliar em floresta – Reserva Biológica do Cuieiras – ZF2, Manaus [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 427 - 436 |
article | |
BibTeX:
@article{marques-filho_radiacao_2005, author = {Marques-Filho, A.O. and Dallarosa, R.G. and Pachêco, V.B.}, title = {Radiação solar e distribuição vertical de área foliar em floresta – Reserva Biológica do Cuieiras – ZF2, Manaus}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {427 -- 436} } |
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Marques Júnior, R., Campos, M., Oliveira, I., Marques júnior, J., Silva, D., Silva D.M.P., J. and Aquino | Variabilidade espacial de atributos físicos de solos antropogênico e não antropogênico na região de Manicoré, AM [BibTeX] |
2014 | Bioscience Journal Vol. 30, pp. 988-997 |
article | |
BibTeX:
@article{marques_junior_variabilidade_2014, author = {Marques Júnior, R.E.; Campos, M.C.C. ; Oliveira, I.A.; Marques júnior, J.; Silva, D.M.P.; Silva, D.M.P., J.; Aquino}, title = {Variabilidade espacial de atributos físicos de solos antropogênico e não antropogênico na região de Manicoré, AM}, journal = {Bioscience Journal}, year = {2014}, volume = {30}, pages = {988--997} } |
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Marques, J., Luizão, F., Teixeira, W. and Ferreira, S.F. | Variações do carbono orgânico dissolvido e de atributos físicos do solo sob diferentes sistemas de uso da terra na Amazônia Central [BibTeX] |
2012 | R. Bras. Ci. Solo Vol. 36, pp. 611-622 |
article | |
BibTeX:
@article{marques_variacoes_2012, author = {Marques, J.D.O. and Luizão, F.J. and Teixeira, W.G. and Ferreira, S.J. F.}, title = {Variações do carbono orgânico dissolvido e de atributos físicos do solo sob diferentes sistemas de uso da terra na Amazônia Central}, journal = {R. Bras. Ci. Solo}, year = {2012}, volume = {36}, pages = {611--622} } |
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Marques, J.D.d.O., Luizão, F.J., Teixeira, W.G., Vitel, C.M. and Marques, E.M.d.A. | Soil organic carbon, carbon stock and their relationships to physical attributes under forest soils in Central Amazonia [BibTeX] |
2016 | Revista Árvore Vol. 40(2), pp. 197-208 |
article | DOI |
BibTeX:
@article{marques_soil_2016, author = {Marques, Jean Dalmo de Oliveira and Luizão, Flávio Jesus and Teixeira, Wenceslau Geraldes and Vitel, Claudia Marie and Marques, Elizalane Moura de Araújo}, title = {Soil organic carbon, carbon stock and their relationships to physical attributes under forest soils in Central Amazonia}, journal = {Revista Árvore}, year = {2016}, volume = {40}, number = {2}, pages = {197--208}, doi = {https://doi.org/10.1590/0100-67622016000200002} } |
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Marques, J.D.d.O., Luizão, F.J., Teixeira, W.G., Sarrazin, M., Ferreira, S.J.F., Beldini, T.P. and Marques, E.M.d.A. | Distribution of organic carbon in different soil fractions in ecosystems of Central Amazonia [BibTeX] |
2015 | R. Bras. Ci. Solo Vol. 39, pp. 232-242 |
article | DOI |
BibTeX:
@article{marques_distribution_2015, author = {Marques, Jean Dalmo de Oliveira and Luizão, Flávio Jesus and Teixeira, Wenceslau Geraldes and Sarrazin, Max and Ferreira, Sávio José Filgueira and Beldini, Troy Patrick and Marques, Elizalane Moura de Araújo}, title = {Distribution of organic carbon in different soil fractions in ecosystems of Central Amazonia}, journal = {R. Bras. Ci. Solo}, year = {2015}, volume = {39}, pages = {232--242}, doi = {https://doi.org/10.1590/01000683rbcs20150142} } |
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Markewitz, D., Resende, J.C.F., Parron, L., Bustamante, M., Klink, C.A., Figueiredo, R.d.O. and Davidson, E.A. | Dissolved rainfall inputs and streamwater outputs in an undisturbed watershed on highly weathered soils in the Brazilian cerrado | 2006 | Hydrological Processes Vol. 20(12), pp. 2615-2639 |
article | DOI URL |
Abstract: The cerrados of Brazil cover 2 million km(2). Despite the extent of these seasonally dry ecosystems, little watershed research has been focused in this region, particularly relative to the watersheds of the Amazon Basin. The cerrado shares pedogenic characteristics with the Amazon Basin in draining portions of the Brazilian shield and in possessing Oxisols over much of the landscape. The objective of this research was to quantify the stream water geochemical relationships of an undisturbed 1200 ha cerrado watershed for comparison to river geochemistry in the Amazon. Furthermore, this undisturbed watershed was used to evaluate stream discharge versus dissolved ion concentration relationships. This research was conducted in the Corrego Roncador watershed of the Reserva Ecologica do Roncador (RECOR) of the Instituto Brasileiro Geografia e Estatistica (IBGE) near Brasilia, Brazil. Bulk precipitation and stream water chemistry were analysed between May 1998 and May 2000. The upland soils of this watershed are nutrient poor possessing total stocks of exchangeable elements in the upper 1 m of 81 +/- 13, 77 +/- 4, 25 +/- 3, and 1 +/- 1 kg ha(-1) of K, Ca, Mg, and P, respectively. Bulk precipitation inputs of dissolved nutrients for this watershed are low and consistent with previous estimates. The nutrient-poor soils of this watershed, however, increase the relative importance of precipitation for nutrient replenishment to vegetation during episodes of ecosystem disturbance. Stream water dissolved loads were extremely dilute with conductivities ranging from 4 to 10 mu S cm(-1) during periods of high- and low-flow, respectively. Despite the low concentrations in this stream, geochemical relationships were similar to other Amazonian streams draining shield geologies. Discharge-concentration relationships for Ca and Mg in these highly weathered soils developed from igneous rocks of the Brazilian shield demonstrated a significant negative relationship indicating a continued predominance of groundwater baseflow contributions these cationic elements. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{markewitz_dissolved_2006, author = {Markewitz, Daniel and Resende, Julio C. F. and Parron, Lucilia and Bustamante, Mercedes and Klink, Carlos A. and Figueiredo, Ricardo de O. and Davidson, Eric A.}, title = {Dissolved rainfall inputs and streamwater outputs in an undisturbed watershed on highly weathered soils in the Brazilian cerrado}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2615--2639}, url = {://WOS:000239670800010}, doi = {https://doi.org/10.1002/hyp.6219} } |
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Markewitz, D., Lamon III, E.C., Bustamante, M.C., Chaves, J., Figueiredo, R.O., Johnson, M.S., Krusche, A., Neill, C. and Silva, J.S.O. | Discharge-calcium concentration relationships in streams of the Amazon and Cerrado of Brazil: soil or land use controlled | 2011 | Biogeochemistry Vol. 105(1-3), pp. 19-35 |
article | DOI URL |
Abstract: Stream discharge-concentration relationships are indicators of terrestrial ecosystem function. Throughout the Amazon and Cerrado regions of Brazil rapid changes in land use and land cover may be altering these hydrochemical relationships. The current analysis focuses on factors controlling the discharge-calcium (Ca) concentration relationship since previous research in these regions has demonstrated both positive and negative slopes in linear log(10)discharge-log(10)Ca concentration regressions. The objective of the current study was to evaluate factors controlling stream discharge-Ca concentration relationships including year, season, stream order, vegetation cover, land use, and soil classification. It was hypothesized that land use and soil class are the most critical attributes controlling discharge-Ca concentration relationships. A multilevel, linear regression approach was utilized with data from 28 streams throughout Brazil. These streams come from three distinct regions and varied broadly in watershed size (textless 1 to textgreater 10(6) ha) and discharge (10(-5.7)-10(3.2) m(3) s(-1)). Linear regressions of log(10)Ca versus log(10)discharge in 13 streams have a preponderance of negative slopes with only two streams having significant positive slopes. An ANOVA decomposition suggests the effect of discharge on Ca concentration is large but variable. Vegetation cover, which incorporates aspects of land use, explains the largest proportion of the variance in the effect of discharge on Ca followed by season and year. In contrast, stream order, land use, and soil class explain most of the variation in stream Ca concentration. In the current data set, soil class, which is related to lithology, has an important effect on Ca concentration but land use, likely through its effect on runoff concentration and hydrology, has a greater effect on discharge-concentration relationships. | |||||
BibTeX:
@article{markewitz_discharge-calcium_2011, author = {Markewitz, Daniel and Lamon, III, E. Conrad and Bustamante, Mercedes C. and Chaves, Joaquin and Figueiredo, Ricardo O. and Johnson, Mark S. and Krusche, Alex and Neill, Christopher and Silva, Jose S. O.}, title = {Discharge-calcium concentration relationships in streams of the Amazon and Cerrado of Brazil: soil or land use controlled}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {19--35}, url = {://WOS:000294501100003}, doi = {https://doi.org/10.1007/s10533-011-9574-2} } |
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Markewitz, D., Figueiredo, R., Carvalho, C.d. and Davidson, E. | Soil and tree response to P fertilization in a secondary tropical forest supported by an Oxisol [BibTeX] |
2012 | Biol Fertil Soils, pp. http://dx.doi.org/10.3334/ORNLDAAC/1074 | article | DOI |
BibTeX:
@article{markewitz_soil_2012, author = {Markewitz, D. and Figueiredo, R.O. and Carvalho, C.J.R. de and Davidson, E.A.}, title = {Soil and tree response to P fertilization in a secondary tropical forest supported by an Oxisol}, journal = {Biol Fertil Soils}, year = {2012}, pages = {http://dx.doi.org/10.3334/ORNLDAAC/1074}, doi = {https://doi.org/10.1007/s00374-011-0659-9} } |
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Markewitz, D., Figueiredo, R.D. and Davidson, E.A. | CO2-driven cation leaching after tropical forest clearing | 2006 | Journal of Geochemical Exploration Vol. 88(1-3), pp. 214-219 |
article | DOI URL |
Abstract: The objective of this study was to investigate the role of dissolved CO2 (H2CO3*) as a mechanism of cation removal from surface soils under secondary land uses in the tropics. Soil leachate columns were prepared with 0-10 cm soils from mature and secondary forest, and managed pastures, and extracted with H2CO3* from deionized water equilibrated with 0%, 0.5%, 1%, and 10% CO2 (g). Extraction of soil cations slowed over time following an exponential form for the cumulative data. The rate of cation concentration decline varied as a function of CO2 concentration with the 10% solution resulting in a greater percent decline with extraction volume. Potassium removal from the exchange sites of all soils and for all solutions was nearly complete ranging from 85% to 97% while removals of Mg (31% to 71%) and Ca (12% to 42%) were lower. The asymptotic patterns of cation loss observed in this study suggest that H2CO3* acid-driven losses of cations may become self-limiting over time. Other stronger acids from atmospheric deposition or organic sources may serve to perpetuate cation removal, and re-forestation on these cleared lands would certainly re-distribute cations from soils to vegetation. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{markewitz_co2-driven_2006, author = {Markewitz, D. and Figueiredo, R. D. and Davidson, E. A.}, title = {CO2-driven cation leaching after tropical forest clearing}, journal = {Journal of Geochemical Exploration}, year = {2006}, volume = {88}, number = {1-3}, pages = {214--219}, url = {://WOS:000235638900049}, doi = {https://doi.org/10.1016/j.gexplo.2005.08.042} } |
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Markewitz, D., Devine, S., Davidson, E.A., Brando, P. and Nepstad, D.C. | Soil moisture depletion under simulated drought in the Amazon: impacts on deep root uptake | 2010 | New Phytologist Vol. 187(3), pp. 592-607 |
article | DOI URL |
Abstract: PtextgreaterDeep root water uptake in tropical Amazonian forests has been a major discovery during the last 15 yr. However, the effects of extended droughts, which may increase with climate change, on deep soil moisture utilization remain uncertain. The current study utilized a 1999-2005 record of volumetric water content (VWC) under a throughfall exclusion experiment to calibrate a one-dimensional model of the hydrologic system to estimate VWC, and to quantify the rate of root uptake through 11.5 m of soil. Simulations with root uptake compensation had a relative root mean square error (RRMSE) of 11% at 0-40 cm and textless 5% at 350-1150 cm. The simulated contribution of deep root uptake under the control was c. 20% of water demand from 250 to 550 cm and c. 10% from 550 to 1150 cm. Furthermore, in years 2 (2001) and 3 (2002) of throughfall exclusion, deep root uptake increased as soil moisture was available but then declined to near zero in deep layers in 2003 and 2004. Deep root uptake was limited despite high VWC (i.e. textgreater 0.30 cm3 cm-3). This limitation may partly be attributable to high residual water contents (theta(r)) in these high-clay (70-90%) soils or due to high soil-to-root resistance. The ability of deep roots and soils to contribute increasing amounts of water with extended drought will be limited. | |||||
BibTeX:
@article{markewitz_soil_2010, author = {Markewitz, Daniel and Devine, Scott and Davidson, Eric A. and Brando, Paulo and Nepstad, Daniel C.}, title = {Soil moisture depletion under simulated drought in the Amazon: impacts on deep root uptake}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {592--607}, note = {Edition: 2010/07/28}, url = {://WOS:000280122500008}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03391.x} } |
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Markewitz, D., Davidson, E.A., Figueiredo, R.D.O., Victoria, R.L. and Krusche, A.V. | Control of cation concentrations in stream waters by surface soil processes in an Amazonian watershed | 2001 | Nature Vol. 410(6830), pp. 802-805 |
article | DOI URL |
Abstract: The chemical composition of ground waters and stream waters is thought to be determined primarily by weathering of parent rock(1-5). In relatively young soils such as those occurring in most temperate ecosystems, dissolution of primary minerals by carbonic acid is the predominant weathering pathway that liberates Ca2+, Mg2+ and K+ and generates alkalinity in the hydrosphere(6). But control of water chemistry in old and highly weathered soils that have lost reservoirs of primary minerals (a common feature of many tropical soils) is less well understood. Here we present soil and water chemistry data from a 10,000-hectare watershed on highly weathered soil in the Brazilian Amazon. Streamwater cation concentrations and alkalinity are positively correlated to each other and to streamwater discharge, suggesting that cations and bicarbonate are mainly flushed from surface soil layers by rainfall rather than being the products of deep soil weathering carried by groundwater flow. These patterns contrast with the seasonal patterns widely recognized in temperate ecosystems with less strongly weathered soils(2,7). In this particular watershed, partial forest clearing and burning 30 years previously enriched the soils in cations and so may have increased the observed wet season leaching of cations. Nevertheless, annual inputs and outputs of cations from the watershed are low and nearly balanced, and thus soil cations from forest burning will remain available for forest regrowth over the next few decades. Our observations suggest that increased root and microbial respiration during the wet season generates CO2 that drives cation-bicarbonate leaching, resulting in a biologically mediated process of surface soil exchange controlling the streamwater inputs of cations and alkalinity from these highly weathered soils. | |||||
BibTeX:
@article{markewitz_control_2001, author = {Markewitz, D. and Davidson, E. A. and Figueiredo, R. D. O. and Victoria, R. L. and Krusche, A. V.}, title = {Control of cation concentrations in stream waters by surface soil processes in an Amazonian watershed}, journal = {Nature}, year = {2001}, volume = {410}, number = {6830}, pages = {802--805}, note = {Edition: 2001/04/12}, url = {://WOS:000168021900051}, doi = {https://doi.org/10.1038/35071052} } |
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Markewitz, D., Davidson, E., Moutinho, P. and Nepstad, D. | Nutrient loss and redistribution after forest clearing on a highly weathered soil in Amazonia | 2004 | Ecological Applications Vol. 14(4), pp. S177-S199 |
article | URL |
Abstract: Over the past three decades, tropical forest clearing and burning have greatly altered the Amazonian landscape by increasing the cover of pastures and secondary forests. The alteration of biogeochemical processes on these lands is of particular interest on highly weathered Oxisols that cover large areas in the region because of concerns regarding possible nutrient limitation in agricultural land uses and during forest regrowth. The objectives of this study were to quantify (1) the reaccumulation of nutrients in biomass of secondary land uses, (2) changes in soil nutrient contents, (3) internal nutrient cycles, and (4) input-output budgets for the landscape mosaic. Nutrient stocks and fluxes were quantified from 1996 to 1998 in mature forest, 19-yr-old secondary forest, degraded pastureland, and managed pastureland in the Brazilian state of Para. Mature forests contain 130 Mg C/ha in aboveground biomass while secondary forest, degraded pasture, and managed pasture contain 34, 4, and 3 Mg C/ha, respectively. Reaccumulation of N, P, K, Ca, and Mg in aboveground biomass of secondary forest was 20%, 21%, 42%, 50%, and 27% of that present in mature forest, while degraded pasture contained 2%, 4%, 15%, 11%, and 6%. Managed pasture had similar accumulations as degraded pasture except for Ca (3%). Changes in soil stocks of C, N, and P were not detected among land uses, except in fertilized managed pastures,, where total soil P (0-10 cm) was elevated. Conversely, Mehlich-III-extractable P of all secondary lands were very low (textless1 mug/g) and were I kg/ha less than contents (0-10 cm) in mature forest. NaOH-extractable P was present in 100-fold higher concentrations and may gradually contribute to meeting plant demands over decadal time scales. Soil cation contents.(0-20 cm) were elevated in secondary lands with increases of similar to85, 500, and 75 kg/ha for K, Ca, and Mg respectively. These increases could account for a substantial portion of cation contents originally in the aboveground biomass of mature forest. The recycling of nutrients through similar to9.0 Mg(.)ha(-1.)yr(-1) of litterfall in secondary forest of 132, 2.8, 32, 106, and 23. kg(.)ha(-1.)yr(-1) for N, P, K, Ca, and Mg, respectively, is similar to mature forest. Nutrient returns in both pasturelands were smaller for all elements except K, which was similar to the forested sites. In these pasture ecosystems, grass turnover has rep laced litterfall return as the predominate mechanism of nutrient recycling. Soil solution fluxes of total N were higher in mature forest (12 kg(.)ha(-1.)yr(-1) at 25 cm depth) compared to secondary lands (textless4 kg(.)ha(-1.)yr(-1)), indicating that cycling of available forms of N has diminished; Conversely, fluxes of cationic elements appear elevated in secondary lands and are charge balanced in solution by HCO3- derived from biological activity in the soil surface. Despite detectable increases in soil cation fluxes, rainwater inputs and stream water outputs of these elements across the watershed were not significantly different. The aggregate picture for this landscape is one in which the secondary forest, although still of smaller stature and lower in species diversity compared to mature forest, is recuperating important nutrient cycling functions. Conversely, pasturelands, which dominate the landscape, are not only of smaller stature, but are also accumulating and cycling a smaller total mass of nutrients. This ecosystem conversion has released C and N from biomass mostly to the atmosphere and has redistributed K, Ca, and Mg from biomass mostly to the soil. Presently, base cation enriched soils are slowly re-equilibrating to an acidic condition through decadal-scale processes of plant uptake and, biogenically driven soil leaching. Our mass balance approach has revealed low soil available N and P diminished rates of cycling of these elements in secondary lands, and low precipitation inputs of P, which may constrain long-term recuperation of ecosystem carbon. | |||||
BibTeX:
@article{markewitz_nutrient_2004, author = {Markewitz, D. and Davidson, E. and Moutinho, P. and Nepstad, D.}, title = {Nutrient loss and redistribution after forest clearing on a highly weathered soil in Amazonia}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S177--S199}, url = {://WOS:000223269000016} } |
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Marimon, B.S., Marimon-Junior, B.H., Feldpausch, T.R., Oliveira-Santos, C., Mews, H.A., Lopez-Gonzalez, G., Lloyd, J., Franczak, D.D., Oliveira, E.A.d., Maracahipes, L., Miguel, A., Lenza, E. and Phillips, O.L. | Disequilibrium and hyperdynamic tree turnover at the forest–cerrado transition zone in southern Amazonia [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 281-292 |
article | |
BibTeX:
@article{marimon_disequilibrium_2014, author = {Marimon, Beatriz S. and Marimon-Junior, Ben Hur and Feldpausch, Ted R. and Oliveira-Santos, Claudinei and Mews, Henrique A. and Lopez-Gonzalez, Gabriela and Lloyd, Jon and Franczak, Daniel D. and Oliveira, Edmar A. de and Maracahipes, Leandro and Miguel, Aline and Lenza, Eddie and Phillips, Oliver L.}, title = {Disequilibrium and hyperdynamic tree turnover at the forest–cerrado transition zone in southern Amazonia}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {281--292} } |
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Marengo, J., Tomasella, J., Soares, W., Alves, L. and Nobre, C. | Extreme climatic events in the Amazon basin Climatological and hydrological context of recent floods [BibTeX] |
2012 | Theoretical and Applied Climatology Vol. 107(1-2), pp. 73-85 |
article | |
BibTeX:
@article{marengo_extreme_2012, author = {Marengo, J.A. and Tomasella, J. and Soares, W.R. and Alves, L.M. and Nobre, C.A.}, title = {Extreme climatic events in the Amazon basin Climatological and hydrological context of recent floods}, journal = {Theoretical and Applied Climatology}, year = {2012}, volume = {107}, number = {1-2}, pages = {73--85} } |
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Marengo, J.A., Tomasella, J., Alves, L.M., Soares, W.R. and Rodriguez, D.A. | The drought of 2010 in the context of historical droughts in the Amazon region | 2011 | Geophysical Research Letters Vol. 38 |
article | DOI URL |
Abstract: The year 2010 featured a widespread drought in the Amazon rain forest, which was more severe than the "once-in-a-century" drought of 2005. Water levels of major Amazon tributaries fell drastically to unprecedented low values, and isolated the floodplain population whose transportation depends upon on local streams which completely dried up. The drought of 2010 in Amazonia started in early austral summer during El Nino and then was intensified as a consequence of the warming of the tropical North Atlantic. An observed tendency for an increase in dry and very dry events, particularly in southern Amazonia during the dry season, is concomitant with an increase in the length of the dry season. Our results suggest that it is by means of a longer dry season that warming in the tropical North Atlantic affects the hydrology of the Amazon Rivers at the end of the recession period (austral spring). This process is, sometimes, further aggravated by deficient rainfall in the previous wet season. Citation: Marengo, J. A., J. Tomasella, L. M. Alves, W. R. Soares, and D. A. Rodriguez (2011), The drought of 2010 in the context of historical droughts in the Amazon region, Geophys. Res. Lett., 38, L12703, doi:10.1029/2011GL047436. | |||||
BibTeX:
@article{marengo_drought_2011, author = {Marengo, Jose A. and Tomasella, Javier and Alves, Lincoln M. and Soares, Wagner R. and Rodriguez, Daniel A.}, title = {The drought of 2010 in the context of historical droughts in the Amazon region}, journal = {Geophysical Research Letters}, year = {2011}, volume = {38}, url = {://WOS:000292107000002}, doi = {https://doi.org/10.1029/2011gl047436} } |
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Marengo, J.A., Nobre, C.A., Tomasella, J., Oyama, M.D., De Oliveira, G.S., De Oliveira, R., Camargo, H., Alves, L.M. and Brown, I.F. | The drought of Amazonia in 2005 | 2008 | Journal of Climate Vol. 21(3), pp. 495-516 |
article | DOI URL |
Abstract: In 2005, large sections of southwestern Amazonia experienced one of the most intense droughts of the last hundred years. The drought severely affected human population along the main channel of the Amazon River and its western and southwestern tributaries, the Solimoes (also known as the Amazon River in the other Amazon countries) and the Madeira Rivers, respectively. The river levels fell to historic low levels and navigation along these rivers had to be suspended. The drought did not affect central or eastern Amazonia, a pattern different from the El Nino-related droughts in 1926, 1983, and 1998. The choice of rainfall data used influenced the detection of the drought. While most datasets (station or gridded data) showed negative departures from mean rainfall, one dataset exhibited above-normal rainfall in western Amazonia. The causes of the drought were not related to El Nino but to (i) the anomalously warm tropical North Atlantic, (ii) the reduced intensity in northeast trade wind moisture transport into southern Amazonia during the peak summertime season, and (iii) the weakened upward motion over this section of Amazonia, resulting in reduced convective development and rainfall. The drought conditions were intensified during the dry season into September 2005 when humidity was lower than normal and air temperatures were 3 degrees-5 degrees C warmer than normal. Because of the extended dry season in the region, forest fires affected part of southwestern Amazonia. Rains returned in October 2005 and generated flooding after February 2006. | |||||
BibTeX:
@article{marengo_drought_2008, author = {Marengo, Jose A. and Nobre, Carlos A. and Tomasella, Javier and Oyama, Marcos D. and De Oliveira, Gilvan Sampaio and De Oliveira, Rafael and Camargo, Helio and Alves, Lincoln M. and Brown, I. Foster}, title = {The drought of Amazonia in 2005}, journal = {Journal of Climate}, year = {2008}, volume = {21}, number = {3}, pages = {495--516}, note = {Edition: 2008/02/14}, url = {://WOS:000252892900005}, doi = {https://doi.org/10.1175/2007jcli1600.1} } |
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Marengo, J.A., Nobre, C.A., Tomasella, J., Cardoso, M.F. and Oyama, M.D. | Hydro-climatic and ecological behaviour of the drought of Amazonia in 2005 | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1773-1778 |
article | DOI URL |
Abstract: In 2005, southwestern Amazonia experienced the effects of an intense drought that affected life and biodiversity. Several major tributaries as well as parts of the main river itself contained only a fraction of their normal volumes of water, and lakes were drying up. The consequences for local people, animals and the forest itself are impossible to estimate now, but they are likely to be serious. The analyses indicate that the drought was manifested as weak peak river season during autumn to winter as a consequence of a weak summertime season in southwestern Amazonia; the winter season was also accompanied by rainfall that sometimes reached 25% of the climatic value, being anomalously warm and dry and helping in the propagation of fires. Analyses of climatic and hydrological records in Amazonia suggest a broad consensus that the 2005 drought was linked not to El Nino as with most previous droughts in the Amazon, but to warming sea surface temperatures in the tropical North Atlantic Ocean. | |||||
BibTeX:
@article{marengo_hydro-climatic_2008, author = {Marengo, J. A. and Nobre, C. A. and Tomasella, J. and Cardoso, M. F. and Oyama, M. D.}, title = {Hydro-climatic and ecological behaviour of the drought of Amazonia in 2005}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1773--1778}, note = {Edition: 2008/02/14}, url = {://WOS:000254577500008}, doi = {https://doi.org/10.1098/rstb.2007.0015} } |
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Marengo, J.A., Liebmann, B., Kousky, V.E., Filizola, N.P. and Wainer, I.C. | Onset and end of the rainy season in the Brazilian Amazon Basin | 2001 | Journal of Climate Vol. 14(5), pp. 833-852 |
article | DOI URL |
Abstract: Onset and end of the rainy season in the Amazon Basin are examined for the period 1979- 96. The onset and end dates are determined by averaging daily rainfall data from many stations, and then constructing 5- day averages (pentads). Onset (end) is defined as the pentad in which rainfall exceeds (falls below) a given threshold, provided that average rainfall was well below (above) the threshold for several pentads preceding onset (end), and well above (below) the threshold for several pentads after onset (end). For the criteria chosen, the climatological onset progresses toward the southeast, arriving in mid- October, and then toward the mouth of the Amazon, arriving near the end of the year. The end dates are earliest in the southeast and progress toward the north, but withdrawal is slower than onset. The onset dates, however, are quite sensitive to changes in the threshold. If the threshold is doubled, for example, the sense of onset is reversed, with onset occurring toward the northwest. Changes in threshold do not change the direction of the progression of the end of the rainy season. The central Amazon shows the largest variation in the date of onset. In several years, onset in the southeast occurs before that in the central Amazon, but onset near the mouth is always latest. There is an unexpectedly low relationship between the length of the rainy season and total accumulation. Likewise, there is little relationship between the onset (and end) date and the total accumulation. Composites of outgoing longwave radiation and the low- level wind field show that in the central Amazon, onset is associated with an anomalous anticyclone and enhanced trade winds in the Atlantic. Near the mouth of the Amazon, however, onset is associated with large- scale northerly anomalies, and the zonal component of the trade winds is reduced. There is an apparent association between sea surface temperature anomalies in the tropical Atlantic and Pacific and the pentads of onset and end of the rainy season in the northern and central Amazon, and near its mouth. The sense is that a warm Pacific and cold Atlantic result in a delayed onset and early withdrawal. Although the strong El Nino of 1982/ 83 and La Nina 1988/ 89 were examples of a delayed and early onset, respectively, the relationships it still holds these years are not considered. | |||||
BibTeX:
@article{marengo_onset_2001, author = {Marengo, J. A. and Liebmann, B. and Kousky, V. E. and Filizola, N. P. and Wainer, I. C.}, title = {Onset and end of the rainy season in the Brazilian Amazon Basin}, journal = {Journal of Climate}, year = {2001}, volume = {14}, number = {5}, pages = {833--852}, url = {://WOS:000167461300014}, doi = {https://doi.org/10.1175/1520-0442(2001)014%3C0833:oaeotr%3E2.0.co;2} } |
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Marengo, J.A., Liebmann, B., Grimm, A.M., Misra, V., Silva Dias, P.L., Cavalcanti, I.F.A. and Alves, L.M. | Recent developments on the South American monsoon system | 2012 | Int. J. Climatol. Vol. 32(1), pp. 1-21 |
article | DOI URL |
Abstract: This paper reviews recent progress made in our understanding of the functioning and variability of the South American Monsoon System (SAMS) on time scales varying from synoptic to long-term variability and climate change. The SAMS contains one of the most prominent summertime climate patterns in South America, featuring a strong seasonal variability in a region lying between the Amazon and the La Plata Basin. Much of the recent progress is derived from complementary international programs, such as the Monsoon Experiment South America (MESA), as well as from ongoing international programs such as the Large Scale Biosphere Atmosphere Experiment in the Amazon Basin (LBA) and the La Plata Basin (LPB) Regional Hydroclimate Project, which includes the CLARIS LPB Europe-South America Network for Climate Change Assessment and Impact Studies in La Plata Basin Project. The latter assesses atmosphere-land surface interactions, the role of land use changes and aerosols from biomass burning considered as sources of variability and change in the SAMS functioning, characteristics and behaviour. The SAMS region is particularly susceptible to variations of climate due to the importance of hydroelectricity generation and the agricultural base of local economies. Also addressed in this report are projections of climate change and extremes, which are important for impact and vulnerability assessments. This discussion includes the need to identify and understand important processes that control the monsoonal climate, how these processes may vary and change, and how they may interact with key societal sectors, including water resource management, hydroelectric generation, agriculture, and agribusiness. This paper reports on the major contributions of MESA to the knowledge of characteristics, functioning and variability of the SAMS, and is based on recent studies and publications, and can be considered as an update of a previous review by C. S. Vera et al. (2006a). Copyright. 2010 Royal Meteorological Society |
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BibTeX:
@article{marengo_recent_2012, author = {Marengo, J. A. and Liebmann, B. and Grimm, A. M. and Misra, V. and Silva Dias, P. L. and Cavalcanti, I. F. A. and Alves, L. M.}, title = {Recent developments on the South American monsoon system}, journal = {Int. J. Climatol.}, year = {2012}, volume = {32}, number = {1}, pages = {1--21}, url = {://000298733800001}, doi = {https://doi.org/10.1002/Joc.2254} } |
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Marengo, J.A., Fisch, G.F., Alves, L.M., Sousa, N.a.V., Fu, R. and Zhuang, Y. | Meteorological context of the onset and end of the rainy season in Central Amazonia during the 2014-15 Go-Amazon Experiment [BibTeX] |
2017 | Atmos. Chem. Phys. Discuss. | article | DOI |
BibTeX:
@article{marengo_meteorological_2017, author = {Marengo, Jose A. and Fisch, Gilberto F. and Alves, Lincoln M and Sousa, N atanael V. and Fu, Rong and Zhuang, Yizhou}, title = {Meteorological context of the onset and end of the rainy season in Central Amazonia during the 2014-15 Go-Amazon Experiment}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2017}, doi = {https://doi.org/10.5194/acp-2017-22} } |
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Marengo, J.A., Douglas, M.W. and Dias, P.L.S. | The South American low-level jet east of the Andes during the 1999 LBA-TRMM and LBA-WET AMC campaign | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: The present study describes some observed surface and upper-air features of the low-level jet (LLJ) and southerly jet (SJ). Our results suggest the existence of this low-level circulation to the east of the Andes that transports moisture from tropical South America toward the south during the warm/wet season of 1999. We explore the synoptic variability, diurnal variation, and alternations between LLJ and SJ episodes by using a combination of surface and high-resolution upper-air observations (1 to 8 soundings per day) and global reanalysis. Our results show strong synoptic fluctuations; with the LLJ more frequent than SJs. The LLJ has stronger winds in the afternoon and its core of maximum winds is located between 1600 and 2000 m above the surface. Special observational efforts, such as the pilot balloon sounding network in Bolivia (Pan American Climate Studies Sounding Network [PACS-SONET] program), the Large-Scale Biosphere-Atmosphere (LBA) Experiment-WET Atmospheric Mesoscale Campaign (AMC), and Tropical Rainfall Measuring Mission (TRMM)-LBA in Southwest Amazonia, have provided upper-air information with high temporal and spatial resolution to describe the structure of both the LLJ and the SJ during the January-April 1999 period. | |||||
BibTeX:
@article{marengo_south_2002, author = {Marengo, J. A. and Douglas, M. W. and Dias, P. L. S.}, title = {The South American low-level jet east of the Andes during the 1999 LBA-TRMM and LBA-WET AMC campaign}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200047}, doi = {https://doi.org/10.1029/2001jd001188} } |
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Marengo, J.A., Cavalcanti, I.F.A., Satyamurty, P., Trosnikov, I., Nobre, C.A., Bonatti, J.P., Camargo, H., Sampaio, G., Sanches, M.B., Manzi, A.O., Castro, C.A.C., D'Almeida, C., Pezzi, L.P. and Candido, L. | Assessment of regional seasonal rainfall predictability using the CPTEC/COLA atmospheric GCM | 2003 | Climate Dynamics Vol. 21(5-6), pp. 459-475 |
article | DOI URL |
Abstract: This is a study of the annual and interannual variability of regional rainfall produced by the Center for Weather Forecasts and Climate Studies/Center for Ocean, Land and Atmospheric Studies (CPTEC/COLA) atmospheric global climate model. An evaluation is made of a 9-member ensemble run of the model forced by observed global sea surface temperature (SST) anomalies for the 10-year period 1982-1991. The Brier skill score and, Relative Operating Characteristics (ROC) are used to assess the predictability of rainfall and to validate rainfall simulations, in several regions world wide. In general, the annual cycle of precipitation is well simulated by the model for several continental and oceanic regions in the tropics and mid latitudes. Interannual variability of rainfall during the peak rainy season is realistically simulated in Northeast Brazil, Amazonia, central Chile, and southern Argentina-Uruguay, Eastern Africa, and tropical Pacific regions, where the model shows good skill. Some regions, such as northwest Peru-Ecuador, and southern Brazil exhibit a realistic simulation of rainfall anomalies associated with extreme El Nino warming conditions, while in years with neutral or La Nina conditions, the agreement between observed and simulated rainfall anomalies is not always present. In the monsoon regions of the world and in southern Africa, even though the model reproduces the annual cycle of rainfall, the skill of the model is low for the simulation of the interannual variability. This is indicative of mechanisms other than the external SST forcing, such as the effect of land-surface moisture and snow feedbacks or the representation of sub-grid scale processes, indicating the important role of factors other than external boundary forcing. The model captures the well-known signatures of rainfall anomalies of El Nino in 1982-83 and 1986-87, indicating its sensitivity to strong external forcing. In normal years, internal climate variability can affect the predictability of climate in some regions, especially in monsoon areas of the world. | |||||
BibTeX:
@article{marengo_assessment_2003, author = {Marengo, J. A. and Cavalcanti, I. F. A. and Satyamurty, P. and Trosnikov, I. and Nobre, C. A. and Bonatti, J. P. and Camargo, H. and Sampaio, G. and Sanches, M. B. and Manzi, A. O. and Castro, C. A. C. and D'Almeida, C. and Pezzi, L. P. and Candido, L.}, title = {Assessment of regional seasonal rainfall predictability using the CPTEC/COLA atmospheric GCM}, journal = {Climate Dynamics}, year = {2003}, volume = {21}, number = {5-6}, pages = {459--475}, url = {://WOS:000186496700007 http://www.springerlink.com/content/0qredf252ew8mwbp/fulltext.pdf}, doi = {https://doi.org/10.1007/s00382-003-0346-0} } |
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Marengo, J. | On the Hydrological Cycle of the Amazon Basin: A historical review and current State-of-the-art [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 1-19 |
article | |
BibTeX:
@article{marengo_hydrological_2006, author = {Marengo, J.A.}, title = {On the Hydrological Cycle of the Amazon Basin: A historical review and current State-of-the-art}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {1--19} } |
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Marengo, J.A. | Characteristics and spatio-temporal variability of the Amazon River Basin Water Budget | 2005 | Climate Dynamics Vol. 24(1), pp. 11-22 |
article | DOI URL |
Abstract: The spatio-temporal variations of the water budget components in the Amazon region are investigated by using a combination of hydrometeorological observations and moisture fluxes derived from the NCEP/NCAR reanalyses, for the period 1970-1999. The key new finding of this study identifies the major differences in the water balance characteristics and variability between the northern and southern parts of the basin. Our results show that there is a seasonality and interannual variability of the water balance that varies across the basin. At interannual time scales, anomalies in the water balance components in the northern Amazon region show relatively stronger links with tropical Pacific interannual variability. Over the entire region, precipitation exceeds evaporation and the basin acts as a sink of moisture (PtextgreaterE). However, on some occasions the basin can act as a source for moisture (PtextlessE) under extreme conditions, such as those related to deficient rainfall in northern Amazonia during the strong El Nino of 1983. Our estimates of the Amazon region's water balance do not show a closure of the budget, with an average imbalance of almost 50%, suggesting that some of the moisture that converges in the Amazon region is not accounted for. The imbalance is larger over the southern Amazon region than over the northern region, and it also exhibits interannual variability. Large uncertainties are detected in the evaporation and moisture-convergence fields derived from the reanalyses, and in the case of evaporation it can be as large as 10-20% when compared with the few field observations across the basin. Observed precipitation fields derived from station data and from grid-box products also show some discrepancies due to sampling problems and interpolation techniques. The streamflow observed at the mouth of the river is obtained after corrections on the series observed taken at a gauging site almost 200 km inland. However, variability in the evaporation, moisture convergence, and observed rainfall and runoff matches quite well. | |||||
BibTeX:
@article{marengo_characteristics_2005, author = {Marengo, J. A.}, title = {Characteristics and spatio-temporal variability of the Amazon River Basin Water Budget}, journal = {Climate Dynamics}, year = {2005}, volume = {24}, number = {1}, pages = {11--22}, url = {://WOS:000227163400002 http://www.springerlink.com/content/mnvfnjduahlxtvmf/fulltext.pdf}, doi = {https://doi.org/10.1007/s00382-004-0461-6} } |
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Marengo Fisch, G., Morales, C., Vendrame, I.&.D. and J.A., P.C. | Diurnal variability of rainfall in southwest Amazonia during the LBA-TRMM field campaign of the Austral summer 1999 [BibTeX] |
2004 | Acta Amazonica Vol. 34(4), pp. 593 - 603 |
article | |
BibTeX:
@article{marengo_diurnal_2004, author = {Marengo, Fisch, G.; Morales, C.; Vendrame, I. & Dias; P.C., J.A.}, title = {Diurnal variability of rainfall in southwest Amazonia during the LBA-TRMM field campaign of the Austral summer 1999}, journal = {Acta Amazonica}, year = {2004}, volume = {34}, number = {4}, pages = {593 -- 603} } |
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Marengo, J.A. | Interdecadal variability and trends of rainfall across the Amazon basin | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 79-96 |
article | DOI URL |
Abstract: An analysis of decadal and long-term patterns of rainfall has been carried out using a combination of raingauge and gridded rainfall datasets, for the entire Amazon basin and for its northern and southern sub-basins. The study covers the period 1929-98. Rainfall variability and variations in circulation and sea surface temperature fields have been analysed in more detail for the period 1950-98. Negative rainfall trends were identified for the entire Amazon basin, while at the regional level there is a negative trend in northern Amazonia and positive trend in southern Amazonia. Decadal time scale variations in rainfall have been discovered, with periods of relatively drier and wetter conditions, with different behaviour in northern and southern Amazonia. Spectral analyses show decadal time scale variations in southern Amazonia, while northern Amazonia exhibits both interannual and decadal scale variations. Shifts in the rainfall regime in both sections of the Amazon basin were identified as occurring in the mid-1940s and 1970s. After 1975-76, northern Amazonia received less rainfall than before 1975. Changes in the circulation and oceanic fields after 1975 suggest an important role of the warming of the tropical central and eastern Pacific on the decreasing rainfall in northern Amazonia, due to more frequent and intense El Nino events during the relatively dry period 1975-98. | |||||
BibTeX:
@article{marengo_interdecadal_2004, author = {Marengo, J. A.}, title = {Interdecadal variability and trends of rainfall across the Amazon basin}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {79--96}, url = {://WOS:000222024700007}, doi = {https://doi.org/10.1007/s00704-004-0045-8} } |
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Marengo, J., Nobre, C.A., Betts, R.A., Cox, P.M., Sampaio, G. and Salazar, L. | Global Warming and Climate Change in Amazonia: Climate-Vegetation Feedback and Impacts on Water Resources [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 273-292 |
incollection | |
BibTeX:
@incollection{m_keller_global_2009, author = {Marengo, José and Nobre, Carlos A. and Betts, Richard A. and Cox, Peter M. and Sampaio, Gilvan and Salazar, Luis}, title = {Global Warming and Climate Change in Amazonia: Climate-Vegetation Feedback and Impacts on Water Resources}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {273--292} } |
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Marenco, F., Johnson, B., Langridge, J.M., Mulcahy, J., Benedetti, A., Remy, S., Jones, L., Szpek, K., Haywood, J., Longo, K. and Artaxo, P. | On the vertical distribution of smoke in the Amazonian atmosphere during the dry season [BibTeX] |
2015 | Atmos. Chem. Phys. Discuss. Vol. 15, pp. 31739-31780 |
article | DOI |
BibTeX:
@article{marenco_vertical_2015, author = {Marenco, F. and Johnson, B. and Langridge, J. M. and Mulcahy, J. and Benedetti, A. and Remy, S. and Jones, L. and Szpek, K. and Haywood, J. and Longo, K. and Artaxo, P.}, title = {On the vertical distribution of smoke in the Amazonian atmosphere during the dry season}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2015}, volume = {15}, pages = {31739--31780}, doi = {https://doi.org/10.5194/acpd-15-31739-2015} } |
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Marcelino Shiraiwa, S., Borges, W. and Filho N.P. & Raiter, F.T. | GPR para a verificação do nível d’água subterrânea em transição Floresta Amazônica e Cerrado [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 367 - 374 |
article | |
BibTeX:
@article{marcelino_gpr_2005, author = {Marcelino, Shiraiwa, S.; Borges, W.R.; Filho, N.P. & Raiter, F., T.H.}, title = {GPR para a verificação do nível d’água subterrânea em transição Floresta Amazônica e Cerrado}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {367 -- 374} } |
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Mantoani, M.C., Martins, J.A., Martins, L.D., Carotenuto, F., Šantl-Temkiv, T., Morris, C.E., Rodrigues, F. and Gonçalves, F.L.T. | Thirty-Five Years of Aerosol–PBAP in situ Research in Brazil: The Need to Think outside the Amazonian Box | 2023 | Climate Vol. 11(1) |
article | DOI |
Abstract: Aerosols and primary biological aerosol particles (PBAPs) play an important role in regulating the global climate, but information summarizing the available knowledge is limited. Here, we present a systematic review of in situ studies performed in the last 35 years on aerosols–PBAPs in Brazil, with 212 studies encompassing 474 cases. The Amazon rainforest was the most studied biome, represented by 72% of cases, followed by the Atlantic Forest with 18%. Studies focusing the Amazon mostly investigated climate-related issues and aerosol physics, with less than 5% examining the biological identity of aerosols, whereas outside the Amazon, this number reached 16%. Whilst more than half of the cases within Amazon (55%) were held at seven sampling sites only, conclusions were mainly extrapolated to the entire biome. Contrarily, research beyond the Amazon has mostly addressed the temporal and biological characterisation of PBAPs, and not only is it scattered, but also scarce. Regarding sampling efforts, most cases (72%) had fewer than 100 days of sampling, and 60% of them spanned less than half a year of study. We argue that scientists should produce more detailed/complete assessments of aerosols–PBAPs in Brazil as a whole, particularly considering their biological identity, given their importance to global climate regulation. | |||||
BibTeX:
@article{mantoani_thirty-five_2023, author = {Mantoani, Maurício C. and Martins, Jorge A. and Martins, Leila D. and Carotenuto, Federico and Šantl-Temkiv, Tina and Morris, Cindy E. and Rodrigues, Fábio and Gonçalves, Fábio L. T.}, title = {Thirty-Five Years of Aerosol–PBAP in situ Research in Brazil: The Need to Think outside the Amazonian Box}, journal = {Climate}, year = {2023}, volume = {11}, number = {1}, doi = {https://doi.org/10.3390/cli11010017} } |
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Manoli, G., Ivanov, V. and Fatichi, S. | Dry‐Season Greening and Water Stress in Amazonia: The Role of Modeling Leaf Phenology [BibTeX] |
2018 | Journal of Geophysical Research Vol. 123(6), pp. 1909-1926 |
article | DOI |
BibTeX:
@article{manoli_dryseason_2018, author = {Manoli, G. and Ivanov, V.Y. and Fatichi, S.}, title = {Dry‐Season Greening and Water Stress in Amazonia: The Role of Modeling Leaf Phenology}, journal = {Journal of Geophysical Research}, year = {2018}, volume = {123}, number = {6}, pages = {1909--1926}, doi = {https://doi.org/10.1029/2017JG004282} } |
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Mann, M.L., Kaufmann, R.K., Bauer, D., Gopal, S., Vera-Diaz, M.D., Nepstad, D., Merry, F., Kallay, J. and Amacher, G.S. | The economics of cropland conversion in Amazonia: The importance of agricultural rent | 2010 | Ecological Economics Vol. 69(7), pp. 1503-1509 |
article | DOI URL |
Abstract: We use spatially efficient logit models to explore the role of economic incentives on the expansion of cropland in the Mato Grosso region between 2001 and 2004. An empirical measure for agricultural economic rent is used to quantify the desirability of a particular plot of land, which previous research proxies with variables such as distance to roads or urban areas, and simple climatic and edaphic variables. Results indicate that the measure for economic rent provides additional information and explanatory power to one of the most commonly used proxies, distance to roads. As predicted by economic theory, it is not simply access or variation in transportation costs that drives the spatial determinants of agricultural expansion, but the expected total returns from the venture. This suggests that spatially explicit rent models can be used to simulate the location and quantity of land-use change in an economically consistent framework. Such a framework lays the foundation for an enhanced methodology that can evaluate the ability of fiscal policy levers to influence the location of agricultural conversion with the ultimate aim of balancing economic and environmental goals. (C) 2010 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{mann_economics_2010, author = {Mann, M. L. and Kaufmann, R. K. and Bauer, D. and Gopal, S. and Vera-Diaz, M. D. and Nepstad, D. and Merry, F. and Kallay, J. and Amacher, G. S.}, title = {The economics of cropland conversion in Amazonia: The importance of agricultural rent}, journal = {Ecological Economics}, year = {2010}, volume = {69}, number = {7}, pages = {1503--1509}, url = {://000278614100017}, doi = {https://doi.org/10.1016/j.ecolecon.2010.02.008} } |
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Mallmann, C.L., Pereira Filho, W., Dreyer, J.B.B., Tabaldi, L.A. and Durgante, F.M. | Leaf-Level Field Spectroscopy to Discriminate Invasive Species (Psidium guajava L. and Hovenia dulcis Thunb.) from Native Tree Species in the Southern Brazilian Atlantic Forest [BibTeX] |
2023 | Remote Sensing Vol. 15(3) |
article | DOI |
BibTeX:
@article{mallmann_leaf-level_2023, author = {Mallmann, Caroline L. and Pereira Filho, Waterloo and Dreyer, Jaqueline B. B. and Tabaldi, Luciane A. and Durgante, Flavia M.}, title = {Leaf-Level Field Spectroscopy to Discriminate Invasive Species (Psidium guajava L. and Hovenia dulcis Thunb.) from Native Tree Species in the Southern Brazilian Atlantic Forest}, journal = {Remote Sensing}, year = {2023}, volume = {15}, number = {3}, doi = {https://doi.org/10.3390/rs15030791} } |
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Mallick, I., Boegh, E., Giustarini, L., Schlerf, M., Drewry, D., Hoffmann, L., Von Randow, C., Kruijt, B., Araùjo, A., Saleska, S., Ehleringer, J.R., Domingues, T.f., Ometto, J.P.H.B., Nobre, A.D., De Moraes, O.L.L., Hayek, M., Munger, J.W., Wofsy Steve, K. and Trebs | Canopy-scale biophysical controls of transpiration and evaporation in the Amazon Basin [BibTeX] |
2016 | Hydrology and Earth System Sciences Discussions, pp. 1-50 | article | |
BibTeX:
@article{mallick_canopy-scale_2016, author = {Mallick, Ivonne ; Boegh, Eva ; Giustarini, Laura ; Schlerf, Martin ; Drewry, Darren ; Hoffmann, Lucien ; Von Randow, Celso ; Kruijt, Bart ; Araùjo, Alessandro ; Saleska, Scott ; Ehleringer, James R. ; Domingues, Tomas f. ; Ometto, Jean Pierre H. B. ; Nobre, Antonio D. ; De Moraes, Osvaldo Luiz Leal ; Hayek, Matthew ; Munger, J. William ; Wofsy, Steve, Kaniska ; Trebs}, title = {Canopy-scale biophysical controls of transpiration and evaporation in the Amazon Basin}, journal = {Hydrology and Earth System Sciences Discussions}, year = {2016}, pages = {1--50} } |
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Malhi, Y. and Wright, J. | Spatial patterns and recent trends in the climate of tropical rainforest regions | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 311-329 |
article | DOI URL |
Abstract: We present an analysis of the mean climate and climatic trends of tropical rainforest regions over the period 1960-1998, with the aid of explicit maps of forest cover and climatological databases. Until the mid-1970s most regions showed little trend in temperature, and the western Amazon experienced a net cooling probably associated with an interdecadal oscillation. Since the mid-1970s, all tropical rainforest regions have experienced a strong warming at a mean rate of 0.26 +/- 0.05 degreesC per decade, in synchrony with a global rise in temperature that has been attributed to the anthropogenic greenhouse effect. Over the study period, precipitation appears to have declined in tropical rainforest regions at a rate of 1.0 +/- 0.8% per decade (p textless 5%), declining sharply in northern tropical Africa (at 3-4% per decade), declining marginally in tropical Asia and showing no significant trend in Amazonia. There is no evidence so far of a decline in precipitation in eastern Amazonia, a region thought vulnerable to climate-change-induced drying. The strong drying trend in Africa suggests that this should be a priority study region for understanding the impact of drought on tropical rainforests. We develop and use a dry-season index to study variations in the length and intensity of the dry season. Only African and Indian tropical rainforests appear to have seen a significant increase in dry-season intensity. In terms of interannual variability, the El Nino-Southern Oscillation (ENSO) is the primary driver of temperature variations across the tropics and of precipitation fluctuations for large areas of the Americas and southeast Asia. The relation between ENSO and tropical African precipitation appears less direct. | |||||
BibTeX:
@article{malhi_spatial_2004, author = {Malhi, Y. and Wright, J.}, title = {Spatial patterns and recent trends in the climate of tropical rainforest regions}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {311--329}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100002}, doi = {https://doi.org/10.1098/rstb.2003.1433} } |
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Malhi, Y., Wood, D., Baker, T.R., Wright, J., Phillips, O.L., Cochrane, T., Meir, P., Chave, J., Almeida, S., Arroyo, L., Higuchi, N., Killeen, T.J., Laurance, S.G., Laurance, W.F., Lewis, S.L., Monteagudo, A., Neill, D.A., Vargas, P.N., Pitman, N.C.A., Quesada, C.A., Salomao, R., Silva, J.N.M., Lezama, A.T., Terborgh, J., Martinez, R.V. and Vinceti, B. | The regional variation of aboveground live biomass in old-growth Amazonian forests | 2006 | Global Change Biology Vol. 12(7), pp. 1107-1138 |
article | DOI URL |
Abstract: The biomass of tropical forests plays an important role in the global carbon cycle, both as a dynamic reservoir of carbon, and as a source of carbon dioxide to the atmosphere in areas undergoing deforestation. However, the absolute magnitude and environmental determinants of tropical forest biomass are still poorly understood. Here, we present a new synthesis and interpolation of the basal area and aboveground live biomass of old-growth lowland tropical forests across South America, based on data from 227 forest plots, many previously unpublished. Forest biomass was analyzed in terms of two uncorrelated factors: basal area and mean wood density. Basal area is strongly affected by local landscape factors, but is relatively invariant at regional scale in moist tropical forests, and declines significantly at the dry periphery of the forest zone. Mean wood density is inversely correlated with forest dynamics, being lower in the dynamic forests of western Amazonia and high in the slow-growing forests of eastern Amazonia. The combination of these two factors results in biomass being highest in the moderately seasonal, slow growing forests of central Amazonia and the Guyanas (up to 350 Mg dry weight ha(-1)) and declining to 200-250 Mg dry weight ha(-1) at the western, southern and eastern margins. Overall, we estimate the total aboveground live biomass of intact Amazonian rainforests (area 5.76 x 10(6) km(2) in 2000) to be 93 +/- 23 Pg C, taking into account lianas and small trees. Including dead biomass and belowground biomass would increase this value by approximately 10% and 21%, respectively, but the spatial variation of these additional terms still needs to be quantified. | |||||
BibTeX:
@article{malhi_regional_2006, author = {Malhi, Y. and Wood, D. and Baker, T. R. and Wright, J. and Phillips, O. L. and Cochrane, T. and Meir, P. and Chave, J. and Almeida, S. and Arroyo, L. and Higuchi, N. and Killeen, T. J. and Laurance, S. G. and Laurance, W. F. and Lewis, S. L. and Monteagudo, A. and Neill, D. A. and Vargas, P. N. and Pitman, N. C. A. and Quesada, C. A. and Salomao, R. and Silva, J. N. M. and Lezama, A. T. and Terborgh, J. and Martinez, R. V. and Vinceti, B.}, title = {The regional variation of aboveground live biomass in old-growth Amazonian forests}, journal = {Global Change Biology}, year = {2006}, volume = {12}, number = {7}, pages = {1107--1138}, url = {://WOS:000238352800001}, doi = {https://doi.org/10.1111/j.1365-2486.2006.01120.x} } |
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Malhi, Y., Silman, M., Salinas, N., Bush, M., Meir, P. and Saatchi, S. | Introduction: Elevation gradients in the tropics: laboratories for ecosystem ecology and global change research [BibTeX] |
2010 | Global Change Biology Vol. 16(12), pp. 3171-3175 |
article | DOI URL |
BibTeX:
@article{malhi_introduction_2010, author = {Malhi, Y. and Silman, M. and Salinas, N. and Bush, M. and Meir, P. and Saatchi, S.}, title = {Introduction: Elevation gradients in the tropics: laboratories for ecosystem ecology and global change research}, journal = {Global Change Biology}, year = {2010}, volume = {16}, number = {12}, pages = {3171--3175}, url = {://WOS:000283726600001}, doi = {https://doi.org/10.1111/j.1365-2486.2010.02323.x} } |
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Malhi, Y., Saatchi, S., Girardin, C. and Aragão, L.E.O.C. | The Production, Storage, and Flow of Carbon in Amazonian Forests [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 355-372 |
incollection | |
BibTeX:
@incollection{m_keller_production_2009, author = {Malhi, Yadvinder and Saatchi, Sassan and Girardin, Cecile and Aragão, Luiz E. O. C.}, title = {The Production, Storage, and Flow of Carbon in Amazonian Forests}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {355--372} } |
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Malhi, Y., Rowland, L., Aragão, L.E.O.C. and Fisher, R.A. | New insights into the variability of the tropical land carbon cycle from the El Niño of 2015/2016 [BibTeX] |
2018 | Philosophical Transactions of the Royal Society B: Biological Sciences Vol. 373(1760), pp. 20170298 |
article | DOI URL |
BibTeX:
@article{malhi_new_2018, author = {Malhi, Yadvinder and Rowland, Lucy and Aragão, Luiz E. O. C. and Fisher, Rosie A.}, title = {New insights into the variability of the tropical land carbon cycle from the El Niño of 2015/2016}, journal = {Philosophical Transactions of the Royal Society B: Biological Sciences}, year = {2018}, volume = {373}, number = {1760}, pages = {20170298}, url = {https://royalsocietypublishing.org/doi/abs/10.1098/rstb.2017.0298}, doi = {https://doi.org/10.1098/rstb.2017.0298} } |
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Malhi, Y. and Roman-Cuesta, R.M. | Analysis of lacunarity and scales of spatial homogeneity in IKONOS images of Amazonian tropical forest canopies | 2008 | Remote Sensing of Environment Vol. 112(5), pp. 2074-2087 |
article | DOI URL |
Abstract: Extensive plot studies across Amazonia have demonstrated that there are large regional gradients in forest productivity and that the dynamics of the forests seem to have accelerated substantially in recent decades, with ensuing impacts on forest structure. Most of these sites are, however, one hectare plots nested within a heterogeneous landscape, and a clear need exists to understand the landscape and regional context of these studies. Remote sensing offers the potential to scale up from plot to higher landscape levels but it has proven complex to evaluate forest structure, and therefore biomass patterns in tropical areas, due to saturation, signal noises, and unclear relationships between reflectance values and structural properties, both for optical and radar systems. In this study, we explore the potential of a textural approach to detect landscape and regional variations in the structure of tropical forest canopies, as viewed from high resolution IKONOS satellite imagery. We used lacunarity analysis and a derived variable, the index of translational homogeneity (ITH), as a tool to search for structural and dynamic forest properties within and among different Amazonian landscapes. The main goals of this research were: (1) to examine the sensitivity and robustness of ITH analysis to details of the analysis procedure; (2) to explore the intra- and inter-regional textural properties of a variety of tropical forest canopies [Caxiuana over tilde, Manaus, Sinop, Santarem (Brazil), and Tambopata (Peru)], and (3) to relate textural properties derived,from lacunarity to structural properties of the forest canopy, mainly crown size. Our results show how ITH and lacunarity analyses offer insights into the spatial distribution of structural properties of forest canopies, easily differentiating between terra firme forests and swamp forests. The studied forest canopies are self-similar on length-scales of 5-11 m, and show translational invariance on scales above 20 m (central and western Amazonia) and 30 m (eastern Amazonia) For a restricted range of solar elevation angles, the ITH appears to be determined mainly by the mean size of tree crowns, and by the fraction of large (shadow-generating) trees. (C) 2008 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{malhi_analysis_2008, author = {Malhi, Yadvinder and Roman-Cuesta, Rosa Maria}, title = {Analysis of lacunarity and scales of spatial homogeneity in IKONOS images of Amazonian tropical forest canopies}, journal = {Remote Sensing of Environment}, year = {2008}, volume = {112}, number = {5}, pages = {2074--2087}, url = {://WOS:000255370700013}, doi = {https://doi.org/10.1016/j.rse.2008.01.009} } |
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Malhi, Y., Roberts, T. and Betts, R.A. | Climate change and the fate of the Amazon - Preface [BibTeX] |
2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1727-1727 |
article | DOI URL |
BibTeX:
@article{malhi_climate_2008, author = {Malhi, Yadvinder and Roberts, Timmons and Betts, Richard A.}, title = {Climate change and the fate of the Amazon - Preface}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1727--1727}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500001 http://rstb.royalsocietypublishing.org/content/363/1498/1727.full.pdf}, doi = {https://doi.org/10.1098/rstb.2008.0012} } |
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Malhi, Y., Roberts, J.T., Betts, R.A., Killeen, T.J., Li, W. and Nobre, C.A. | Climate change, deforestation, and the fate of the Amazon | 2008 | Science Vol. 319(5860), pp. 169-172 |
article | DOI URL |
Abstract: The forest biome of Amazonia is one of Earth's greatest biological treasures and a major component of the Earth system. This century, it faces the dual threats of deforestation and stress from climate change. Here, we summarize some of the latest findings and thinking on these threats, explore the consequences for the forest ecosystem and its human residents, and outline options for the future of Amazonia. We also discuss the implications of new proposals to finance preservation of Amazonian forests. | |||||
BibTeX:
@article{malhi_climate_2008-1, author = {Malhi, Yadvinder and Roberts, J. Timmons and Betts, Richard A. and Killeen, Timothy J. and Li, Wenhong and Nobre, Carlos A.}, title = {Climate change, deforestation, and the fate of the Amazon}, journal = {Science}, year = {2008}, volume = {319}, number = {5860}, pages = {169--172}, note = {Edition: 2007/12/01}, url = {://WOS:000252246400030 http://www.sciencemag.org/content/319/5860/169}, doi = {https://doi.org/10.1126/science.1146961} } |
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Malhi, Y., Phillips, O.L., Lloyd, J., Baker, T., Wright, J., Almeida, S., Arroyo, L., Frederiksen, T., Grace, J., Higuchi, N., Killeen, T., Laurance, W.F., Leano, C., Lewis, S., Meir, P., Monteagudo, A., Neill, D., Vargas, P.N., Panfil, S.N., Patino, S., Pitman, N., Quesada, C.A., Rudas-Ll, A., Salomao, R., Saleska, S., Silva, N., Silveira, M., Sombroek, W.G., Valencia, R., Martinez, R.V., Vieira, I.C.G. and Vinceti, B. | An international network to monitor the structure, composition and dynamics of Amazonian forests (RAINFOR) | 2002 | Journal of Vegetation Science Vol. 13(3), pp. 439-450 |
article | DOI URL |
Abstract: The Amazon basin is likely to be increasingly affected by environmental changes: higher temperatures, changes in precipitation, CO2 fertilization and habitat fragmentation. To examine the important ecological and biogeochemical consequences of these changes, we are developing an international network, RAINFOR, which aims to monitor forest biomass and dynamics across Amazonia in a co-ordinated fashion in order to understand their relationship to soil and climate. The network will focus on sample plots established by independent researchers, some providing data extending back several decades. We will also conduct rapid transect studies of poorly monitored regions. Field expeditions analysed local soil and plant properties in the first phase (2001-2002). Initial results suggest that the network has the potential to reveal much information on the continental-scale relations between forest and environment. The network will also serve as a forum for discussion between researchers, with the aim of standardising sampling techniques and methodologies that will enable Amazonian forests to be monitored in a coherent manner in the coming decades. | |||||
BibTeX:
@article{malhi_international_2002, author = {Malhi, Y. and Phillips, O. L. and Lloyd, J. and Baker, T. and Wright, J. and Almeida, S. and Arroyo, L. and Frederiksen, T. and Grace, J. and Higuchi, N. and Killeen, T. and Laurance, W. F. and Leano, C. and Lewis, S. and Meir, P. and Monteagudo, A. and Neill, D. and Vargas, P. N. and Panfil, S. N. and Patino, S. and Pitman, N. and Quesada, C. A. and Rudas-Ll, A. and Salomao, R. and Saleska, S. and Silva, N. and Silveira, M. and Sombroek, W. G. and Valencia, R. and Martinez, R. V. and Vieira, I. C. G. and Vinceti, B.}, title = {An international network to monitor the structure, composition and dynamics of Amazonian forests (RAINFOR)}, journal = {Journal of Vegetation Science}, year = {2002}, volume = {13}, number = {3}, pages = {439--450}, url = {://WOS:000178428000015}, doi = {https://doi.org/10.1111/j.1654-1103.2002.tb02068.x} } |
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Malhi, Y. and Phillips, O.L. | Tropical forests and global atmospheric change: a synthesis | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 549-555 |
article | DOI URL |
Abstract: We present a personal perspective on the highlights of the Theme Issue 'Tropical forests and global atmospheric change'. We highlight the key findings on the contemporary rate of climatic change in the tropics, the evidence-gained from field studies-of large-scale and rapid change in the dynamics and biomass of old-growth forests, and evidence of how climate change and fragmentation can interact to increase the vulnerability of plants and animals to fires. A range of opinions exists concerning the possible cause of these observed changes, but examination of the spatial 'fingerprint' of observed change may help to identify the driving mechanism(s). Studies of changes in tropical forest regions since the last glacial maximum show the sensitivity of species composition and ecology to atmospheric changes. Model studies of change in forest vegetation highlight the potential importance of temperature or drought thresholds that could lead to substantial forest decline in the near future. During the coming century, the Earth's remaining tropical forests face the combined pressures of direct human impacts and a climatic and atmospheric situation not experienced for at least 20 million years. Understanding and monitoring of their response to this atmospheric change are essential if we are to maximize their conservation options. | |||||
BibTeX:
@article{malhi_tropical_2004, author = {Malhi, Y. and Phillips, O. L.}, title = {Tropical forests and global atmospheric change: a synthesis}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {549--555}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100017}, doi = {https://doi.org/10.1098/rstb.2003.1449} } |
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Malhi, Y., Pegoraro, E., Nobre, A.D., Pereira, M.G.P., Grace, J., Culf, A.D. and Clement, R. | Energy and water dynamics of a central Amazonian rain forest | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: This paper presents measurements of the energy and water budgets of a tropical rain forest near Manaus, Brazil, in central Amazonia, collected between September 1995 and August 1996. Fluxes of sensible and latent heat were measured using a three-dimensional eddy covariance system mounted above the forest canopy. Using a new approach to analysis of eddy covariance data, we found that the measured fluxes increased significantly when turbulent transport on timescales of 1 to 4 hours was taken into account. With this new analysis, the measured turbulent fluxes almost balanced the incoming net radiation, giving increased confidence in the accuracy of the measured fluxes. Of the 5.56 GJ m(-2) yr(-1) of solar radiation supplied over the year, 11% were reflected, 15% were lost as net thermal emission, 27% were transported through sensible heat convection, 46% used in evapotranspiration, and 0.5% were used in net carbon fixation. Total annual evapotranspiration was calculated to be 1123 mm, accounting for 54% of total precipitation. Seasonality was an important influence: limited water availability during the dry season caused evapotranspiration to reduce by 50%. Total canopy conductance was linearly correlated to soil moisture content, with typical midday values ranging between 0.8 mol m(-2) s(-1) in the wet season and 0.3 mol m(-2) s(-1) in the dry season. Such seasonal behavior is likely to be prevalent in most tropical forest regions, and correct description of dry-season evapotranspiration will require accurate modeling of plant and soil hydraulic properties and knowledge of root distributions. | |||||
BibTeX:
@article{malhi_energy_2002, author = {Malhi, Y. and Pegoraro, E. and Nobre, A. D. and Pereira, M. G. P. and Grace, J. and Culf, A. D. and Clement, R.}, title = {Energy and water dynamics of a central Amazonian rain forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200045}, doi = {https://doi.org/10.1029/2001jd000623} } |
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Malhi, Y., Nobre, A.D., Grace, J., Kruijt, B., Pereira, M.G.P., Culf, A. and Scott, S. | Carbon dioxide transfer over a Central Amazonian rain forest | 1998 | Journal of Geophysical Research Vol. 103(D24), pp. 31593-31612 |
article | DOI URL |
Abstract: Tropical rain forests are among the most important and least monitored of terrestrial ecosystems. In recent years, their influence on atmospheric concentrations of carbon dioxide and water vapor has become the subject of much speculation. Here we present results from a yearlong study of CO2 fluxes. at a tropical forest in central Amazonia, using the micrometeorological technique of eddy covariance. The diurnal cycle of CO2 flux was consistent with previous shortterm studies in tropical rain forests, implying that the Amazonian rain forest shows a fair degree of spatial uniformity in bulk ecophysiological characteristics. Typical peak daytime photosynthesis rates were 24-28 mu mol CO2 m(-2) s(-1), and respiration rates were 6-8 mu mol CO2 m(-1) s(-1). There was significant seasonality in peak photosynthesis over the year, which appeared strongly correlated with soil moisture content. On the other hand, there was no evidence of strong seasonality in soil respiration. Central Amazonia has only a short, 3 month dry season, not atypical of tropical rain forest, and it is therefore likely that large areas of Amazonia exhibit significant seasonality in photosynthetic capacity. The gross primary production was calculated to be 30 t C ha(-1) yr(-1). An analysis of data quality is included in the appendix. | |||||
BibTeX:
@article{malhi_carbon_1998, author = {Malhi, Y. and Nobre, Antonio D. and Grace, J. and Kruijt, B. and Pereira, Maria G. P. and Culf, A. and Scott, S.}, title = {Carbon dioxide transfer over a Central Amazonian rain forest}, journal = {Journal of Geophysical Research}, year = {1998}, volume = {103}, number = {D24}, pages = {31593--31612}, url = {://WOS:000077967000006 http://www.agu.org/journals/jd/v103/iD24/98JD02647/98JD02647.pdf}, doi = {https://doi.org/10.1029/98jd02647} } |
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Malhi, Y., Melack, J., Gatti, L., Ometto, J., Kesselmeier, J., Wolff, S., Aragão, L., Costa, M., Saleska, S., Pangala, S., Basso, L., Rizzo, L., de Araújo, A., Restrepo-Coupe, N. and Silva-Junior, C. | Capítulo 6: Ciclos Biogeoquímicos de la Amazonía [BibTeX] |
2022 | Vol. Capitulo 6Informe de evaluación de Amazonía 2021, pp. 37p. |
incollection | DOI |
BibTeX:
@incollection{malhi_capitulo_2022, author = {Malhi, Yadvinder and Melack, John and Gatti, Luciana and Ometto, Jean and Kesselmeier, Jürgen and Wolff, Stefan and Aragão, Luiz and Costa, Marcos and Saleska, Scott and Pangala, Sunitha and Basso, Luana and Rizzo, Luciana and de Araújo, Alessandro and Restrepo-Coupe, Natalia and Silva-Junior, Celso}, title = {Capítulo 6: Ciclos Biogeoquímicos de la Amazonía}, booktitle = {Informe de evaluación de Amazonía 2021}, year = {2022}, volume = {Capitulo 6}, pages = {37p.}, note = {Section: Ciclos Biogeoquímicos de la Amazonía}, doi = {https://doi.org/10.55161/FRJG1833} } |
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Malhi, Y., Meir, P. and Brown, S. | Forests, carbon and global climate | 2002 | Philosophical Transactions of the Royal Society of London Series a-Mathematical Physical and Engineering Sciences Vol. 360(1797), pp. 1567-1591 |
article | DOI URL |
Abstract: This review places into context the role that forest ecosystems play in the global carbon cycle, and their potential interactions with climate change. We first examine the natural, preindustrial carbon cycle. Every year forest gross photosynthesis cycles approximately one-twelfth of the atmospheric stock of carbon dioxide, accounting for 50% of terrestrial photosynthesis. This cycling has remained almost constant since the end of the last ice age, but since the Industrial Revolution it has undergone substantial disruption as a result of the injection of 480 PgC into the atmosphere through fossil-fuel combustion and land-use change, including forest clearance. In the second part of this paper we review this 'carbon disruption', and its impact on the oceans, atmosphere and biosphere. Tropical deforestation is resulting in a release of 1.7 PgC yr(-1) into the atmosphere. However, there is also strong evidence for a 'sink' for carbon in natural vegetation (carbon absorption), which can be explained partly by the regrowth of forests on abandoned lands, and partly by a global change factor, the most likely cause being 'fertilization' resulting from the increase in atmospheric CO2. In the 1990s this biosphere sink was estimated to be sequestering 3.2 PgC yr(-1) and is likely to have substantial effects on the dynamics, structure and biodiversity of all forests. Finally, we examine the potential for forest protection and afforestation to mitigate climate change. An extensive global carbon sequestration programme has the potential to make a particularly significant contribution to controlling the rise in CO2 emissions in the next few decades. In the course of the whole century, however, even the maximum amount of carbon that could be sequestered will be dwarfed by the magnitude of (projected) fossil-fuel emissions. Forest carbon sequestration should only be viewed as a component of a mitigation strategy, not as a substitute for the changes in energy supply, use and technology that will be required if atmospheric CO2 concentrations are to be stabilized. | |||||
BibTeX:
@article{malhi_forests_2002, author = {Malhi, Y. and Meir, P. and Brown, S.}, title = {Forests, carbon and global climate}, journal = {Philosophical Transactions of the Royal Society of London Series a-Mathematical Physical and Engineering Sciences}, year = {2002}, volume = {360}, number = {1797}, pages = {1567--1591}, note = {Edition: 2002/12/04}, url = {://WOS:000177340500002}, doi = {https://doi.org/10.1098/rsta.2002.1020} } |
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Malhi, Y. and Grace, J. | Tropical forests and atmospheric carbon dioxide | 2000 | Trends in Ecology & Evolution Vol. 15(8), pp. 332-337 |
article | DOI URL |
Abstract: Tropical forests play a major role in determining the current atmospheric concentration of CO2 as both sources of CO2 following deforestation and sinks of CO2 probably resulting from CO2 stimulation of forest photosynthesis. Recently, researchers have tried to quantify this role. The results suggest that both the carbon sources and sinks in tropical forests are significantly greater than previously thought. | |||||
BibTeX:
@article{malhi_tropical_2000, author = {Malhi, Y. and Grace, J.}, title = {Tropical forests and atmospheric carbon dioxide}, journal = {Trends in Ecology & Evolution}, year = {2000}, volume = {15}, number = {8}, pages = {332--337}, note = {Edition: 2000/07/08}, url = {://WOS:000088403900017}, doi = {https://doi.org/10.1016/s0169-5347(00)01906-6} } |
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Malhi, Y., Doughty, C. and Galbraith, D. | The allocation of ecosystem net primary productivity in tropical forests | 2011 | Philosophical Transactions of the Royal Society B: Biological Sciences Vol. 366(1582), pp. 3225-3245 |
article | DOI URL |
Abstract: The allocation of the net primary productivity (NPP) of an ecosystem between canopy, woody tissue and fine roots is an important descriptor of the functioning of that ecosystem, and an important feature to correctly represent in terrestrial ecosystem models. Here, we collate and analyse a global dataset of NPP allocation in tropical forests, and compare this with the representation of NPP allocation in 13 terrestrial ecosystem models. On average, the data suggest an equal partitioning of allocation between all three main components (mean 34 +/- 6% canopy, 39 +/- 10% wood, 27 +/- 11% fine roots), but there is substantial site-to-site variation in allocation to woody tissue versus allocation to fine roots. Allocation to canopy (leaves, flowers and fruit) shows much less variance. The mean allocation of the ecosystem models is close to the mean of the data, but the spread is much greater, with several models reporting allocation partitioning outside of the spread of the data. Where all main components of NPP cannot be measured, litterfall is a good predictor of overall NPP (r(2) = 0.83 for linear fit forced through origin), stem growth is a moderate predictor and fine root production a poor predictor. Across sites the major component of variation of allocation is a shifting allocation between wood and fine roots, with allocation to the canopy being a relatively invariant component of total NPP. This suggests the dominant allocation trade-off is a 'fine root versus wood' trade-off, as opposed to the expected 'root-shoot' trade-off; such a trade-off has recently been posited on theoretical grounds for old-growth forest stands. We conclude by discussing the systematic biases in estimates of allocation introduced by missing NPP components, including herbivory, large leaf litter and root exudates production. These biases have a moderate effect on overall carbon allocation estimates, but are smaller than the observed range in allocation values across sites. | |||||
BibTeX:
@article{malhi_allocation_2011, author = {Malhi, Y. and Doughty, C. and Galbraith, D.}, title = {The allocation of ecosystem net primary productivity in tropical forests}, journal = {Philosophical Transactions of the Royal Society B: Biological Sciences}, year = {2011}, volume = {366}, number = {1582}, pages = {3225--3245}, note = {Edition: 2011/10/19}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22006964 http://rstb.royalsocietypublishing.org/content/366/1582/3225.full.pdf}, doi = {https://doi.org/10.1098/rstb.2011.0062} } |
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Malhi, Y. and Davidson, E.A. | Biogeochemistry and Ecology of Terrestrial Ecosystems of Amazonia [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 293-298 |
incollection | |
BibTeX:
@incollection{m_keller_biogeochemistry_2009, author = {Malhi, Y. and Davidson, Eric A.}, title = {Biogeochemistry and Ecology of Terrestrial Ecosystems of Amazonia}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {293--298} } |
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Malhi, Y., Baker, T.R., Phillips, O.L., Almeida, S., Alvarez, E., Arroyo, L., Chave, J., Czimczik, C.I., Di Fiore, A., Higuchi, N., Killeen, T.J., Laurance, S.G., Laurance, W.F., Lewis, S.L., Montoya, L.M.M., Monteagudo, A., Neill, D.A., Vargas, P.N., Patino, S., Pitman, N.C.A., Quesada, C.A., Salomao, R., Silva, J.N.M., Lezama, A.T., Martinez, R.V., Terborgh, J., Vinceti, B. and Lloyd, J. | The above-ground coarse wood productivity of 104 Neotropical forest plots | 2004 | Global Change Biology Vol. 10(5), pp. 563-591 |
article | DOI URL |
Abstract: The net primary production of tropical forests and its partitioning between long-lived carbon pools (wood) and shorter-lived pools (leaves, fine roots) are of considerable importance in the global carbon cycle. However, these terms have only been studied at a handful of field sites, and with no consistent calculation methodology. Here we calculate above-ground coarse wood carbon productivity for 104 forest plots in lowland New World humid tropical forests, using a consistent calculation methodology that incorporates corrections for spatial variations in tree-size distributions and wood density, and for census interval length. Mean wood density is found to be lower in more productive forests. We estimate that above-ground coarse wood productivity varies by more than a factor of three (between 1.5 and 5.5 Mg C ha(-1) a(-1)) across the Neotropical plots, with a mean value of 3.1 Mg C ha(-1) a(-1). There appear to be no obvious relationships between wood productivity and rainfall, dry season length or sunshine, but there is some hint of increased productivity at lower temperatures. There is, however, also strong evidence for a positive relationship between wood productivity and soil fertility. Fertile soils tend to become more common towards the Andes and at slightly higher than average elevations, so the apparent temperature/productivity relationship is probably not a direct one. Coarse wood productivity accounts for only a fraction of overall tropical forest net primary productivity, but the available data indicate that it is approximately proportional to total above-ground productivity. We speculate that the large variation in wood productivity is unlikely to directly imply an equivalent variation in gross primary production. Instead a shifting balance in carbon allocation between respiration, wood carbon and fine root production seems the more likely explanation. | |||||
BibTeX:
@article{malhi_above-ground_2004, author = {Malhi, Y. and Baker, T. R. and Phillips, O. L. and Almeida, S. and Alvarez, E. and Arroyo, L. and Chave, J. and Czimczik, C. I. and Di Fiore, A. and Higuchi, N. and Killeen, T. J. and Laurance, S. G. and Laurance, W. F. and Lewis, S. L. and Montoya, L. M. M. and Monteagudo, A. and Neill, D. A. and Vargas, P. N. and Patino, S. and Pitman, N. C. A. and Quesada, C. A. and Salomao, R. and Silva, J. N. M. and Lezama, A. T. and Martinez, R. V. and Terborgh, J. and Vinceti, B. and Lloyd, J.}, title = {The above-ground coarse wood productivity of 104 Neotropical forest plots}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {563--591}, url = {://WOS:000221421600004 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00778.x/asset/j.1529-8817.2003.00778.x.pdf?v=1&t=h6hwf5qt&s=83eb905676ec7720526339c35870c7f2ac08442e}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00778.x} } |
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Malhi, Y., Aragao, L.E.O.C., Metcalfe, D., Paiva, R., Quesada, C.A., Almeida, S., Anderson, L.O., Brando, P., Chambers, J.Q., da Costa, A.C.L., Hutyra, L., Oliveira, P.J., Patino, S., Pyle, E., Robertson, A. and Teixeira, L.M. | Comprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests | 2009 | Global Change Biology Vol. 15(5), pp. 1255-1274 |
article | DOI URL |
Abstract: The allocation and cycling of carbon (C) within forests is an important component of the biospheric C cycle, but is particularly understudied within tropical forests. We synthesise reported and unpublished results from three lowland rainforest sites in Amazonia (in the regions of Manaus, Tapajos and Caxiuana), all major sites of the Large-Scale Biosphere-Atmosphere Programme (LBA). We attempt a comprehensive synthesis of the C stocks, nutrient status and, particularly, the allocation and internal C dynamics of all three sites. The calculated net primary productivities (NPP) are 10.1 +/- 1.4 Mg C ha(-1) yr(-1) (Manaus), 14.4 +/- 1.3 Mg C ha(-1) yr(-1) (Tapajos) and 10.0 +/- 1.2 Mg C ha(-1) yr(-1) (Caxiuana). All errors bars report standard errors. Soil and leaf nutrient analyses indicate that Tapajos has significantly more plant-available phosphorus and calcium. Autotrophic respiration at all three sites (14.9-21.4 Mg C ha yr(-1)) is more challenging to measure, with the largest component and greatest source of uncertainty being leaf dark respiration. Comparison of measured soil respiration with that predicted from C cycling measurements provides an independent constraint. It shows general good agreement at all three sites, with perhaps some evidence for measured soil respiration being less than expected. Twenty to thirty percent of fixed C is allocated belowground. Comparison of gross primary productivity (GPP), derived from ecosystem flux measurements with that derived from component studies (NPP plus autotrophic respiration) provides an additional crosscheck. The two approaches are in good agreement, giving increased confidence in both approaches to estimating GPP. The ecosystem carbon-use efficiency (CUEs), the ratio of NPP to GPP, is similar at Manaus (0.34 +/- 0.10) and Caxiuana (0.32 +/- 0.07), but may be higher at Tapajos (0.49 +/- 0.16), although the difference is not significant. Old growth or infertile tropical forests may have low CUE compared with recently disturbed and/or fertile forests. | |||||
BibTeX:
@article{malhi_comprehensive_2009, author = {Malhi, Y. and Aragao, L. E. O. C. and Metcalfe, D.B. and Paiva, R. and Quesada, C. A. and Almeida, S. and Anderson, L. O. and Brando, P. and Chambers, J. Q. and da Costa, A. C. L. and Hutyra, L.R. and Oliveira, P. J. and Patino, S. and Pyle, E.H. and Robertson, A.L. and Teixeira, L. M.}, title = {Comprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests}, journal = {Global Change Biology}, year = {2009}, volume = {15}, number = {5}, pages = {1255--1274}, url = {://WOS:000265033700015}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01780.x} } |
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Malhi, Y., Aragao, L.E.O.C., Galbraith, D., Huntingford, C., Fisher, R., Zelazowski, P., Sitch, S., McSweeney, C. and Meir, P. | Exploring the likelihood and mechanism of a climate-change-induced dieback of the Amazon rainforest | 2009 | Proceedings of the National Academy of Sciences of the United States of America Vol. 106(49), pp. 20610-20615 |
article | DOI URL |
Abstract: We examine the evidence for the possibility that 21st-century climate change may cause a large-scale "dieback'' or degradation of Amazonian rainforest. We employ a new framework for evaluating the rainfall regime of tropical forests and from this deduce precipitation-based boundaries for current forest viability. We then examine climate simulations by 19 global climate models (GCMs) in this context and find that most tend to underestimate current rainfall. GCMs also vary greatly in their projections of future climate change in Amazonia. We attempt to take into account the differences between GCM-simulated and observed rainfall regimes in the 20th century. Our analysis suggests that dry-season water stress is likely to increase in E. Amazonia over the 21st century, but the region tends toward a climate more appropriate to seasonal forest than to savanna. These seasonal forests may be resilient to seasonal drought but are likely to face intensified water stress caused by higher temperatures and to be vulnerable to fires, which are at present naturally rare in much of Amazonia. The spread of fire ignition associated with advancing deforestation, logging, and fragmentation may act as nucleation points that trigger the transition of these seasonal forests into fire-dominated, low biomass forests. Conversely, deliberate limitation of deforestation and fire may be an effective intervention to maintain Amazonian forest resilience in the face of imposed 21st-century climate change. Such intervention may be enough to navigate E. Amazonia away from a possible "tipping point,'' beyond which extensive rainforest would become unsustainable. | |||||
BibTeX:
@article{malhi_exploring_2009, author = {Malhi, Yadvinder and Aragao, Luiz E. O. C. and Galbraith, David and Huntingford, Chris and Fisher, Rosie and Zelazowski, Przemyslaw and Sitch, Stephen and McSweeney, Carol and Meir, Patrick}, title = {Exploring the likelihood and mechanism of a climate-change-induced dieback of the Amazon rainforest}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2009}, volume = {106}, number = {49}, pages = {20610--20615}, note = {Edition: 2009/02/17}, url = {://WOS:000272553000013}, doi = {https://doi.org/10.1073/pnas.0804619106} } |
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Malhi, Y., Amézquita, F.F., Doughty, C.E., Silva-Espejo, J.E., Girardin, C.A., Metcalfe, D.B., Aragão, L.E., Huaraca-Quispe, L.P., Alzamora-Taype, I., Eguiluz-Mora, L., Marthews, T.R., Halladay, K., Quesada, C.A., Robertson, A.L., Fisher, J.B., Zaragoza-Castells, J., Rojas-Villagra, C.M., Pelaez-Tapia, Y., Salinas, N., Meir, P. and Phillips, O.L. | The productivity, metabolism and carbon cycle of two lowland tropical forest plots in south-western Amazonia, Peru [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 85-105 |
article | |
BibTeX:
@article{malhi_productivity_2014, author = {Malhi, Yadvinder and Amézquita, Filio Farfán and Doughty, Christopher E. and Silva-Espejo, Javier E. and Girardin, Cécile A.J. and Metcalfe, Daniel B. and Aragão, Luiz E.O.C. and Huaraca-Quispe, Lidia P. and Alzamora-Taype, Ivonne and Eguiluz-Mora, Luzmilla and Marthews, Toby R. and Halladay, Kate and Quesada, Carlos A. and Robertson, Amanda L. and Fisher, Joshua B. and Zaragoza-Castells, Joana and Rojas-Villagra, Clara M. and Pelaez-Tapia, Yulina and Salinas, Norma and Meir, Patrick and Phillips, Oliver L.}, title = {The productivity, metabolism and carbon cycle of two lowland tropical forest plots in south-western Amazonia, Peru}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {85--105} } |
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Malhi, Y. | The productivity, metabolism and carbon cycle of tropical forest vegetation | 2012 | Journal of Ecology Vol. 100(1), pp. 65-75 |
article | DOI URL |
Abstract: 1. Tropical forests account for one-third of the total metabolic activity of the Earths land surface. Hence, understanding the controls on tropical forest photosynthesis and respiration, and the allocation of the products of photosynthesis to canopy, woody tissue and rhizosphere, is important to understand global ecosystem functioning. | |||||
BibTeX:
@article{malhi_productivity_2012, author = {Malhi, Y.}, title = {The productivity, metabolism and carbon cycle of tropical forest vegetation}, journal = {Journal of Ecology}, year = {2012}, volume = {100}, number = {1}, pages = {65--75}, url = {://000298014400006}, doi = {https://doi.org/10.1111/j.1365-2745.2011.01916.x} } |
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Malhi, Y. | The carbon balance of tropical forest regions, 1990-2005 | 2010 | Current Opinion in Environmental Sustainability Vol. 2(4), pp. 237-244 |
article | DOI URL |
Abstract: Global awareness of the significance of the role that tropical forests play in the global carbon cycle has never been greater, but much uncertainty still exists as to the exact magnitude of this role. Here I review and attempt to synthesise the latest evidence of both the carbon source from tropical forest conversion, and the carbon sink in tropical vegetation. Tropical biome conversion is estimated to be a source of 1.3 +/- 0.2 Pg C year(-1) to the atmosphere in both periods 1990-1999 and 2000-2005, whereas intact tropical biomes were estimated to be a net carbon sink of 1.1 +/- 0.3 Pg C year(-1). The ratios of carbon source to carbon sink are very different for the different tropical continents, reflecting different rates of conversion and different area of forest cover, with tropical Asia probably a strong net carbon source and tropical Africa probably a strong net sink. The net balance of the tropical forest biomes is estimated to be +0.2 +/- 0.4 Pg C year(-1) (not significantly different from zero) over both periods 1990-1999 and 2000-2005; this result is consistent with that from atmospheric inversion models that better represent vertical CO(2) profiles (+0.1 +/- 0.3 Pg C year(-1)). | |||||
BibTeX:
@article{malhi_carbon_2010, author = {Malhi, Y.}, title = {The carbon balance of tropical forest regions, 1990-2005}, journal = {Current Opinion in Environmental Sustainability}, year = {2010}, volume = {2}, number = {4}, pages = {237--244}, url = {://000283805300006}, doi = {https://doi.org/10.1016/j.cosust.2010.08.002} } |
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Malhi, Y. | Carbon in the atmosphere and terrestrial biosphere in the 21st century | 2002 | Philosophical Transactions of the Royal Society of London Series a-Mathematical Physical and Engineering Sciences Vol. 360(1801), pp. 2925-2945 |
article | DOI URL |
Abstract: The release of carbon dioxide from fossil-fuel combustion and land-use change has caused a significant perturbation in the natural cycling of carbon between land, atmosphere and oceans. Understanding and managing the effects of this disruption on atmospheric composition and global climate are likely to be amongst the most pressing issues of the 21st century. However, the present-day carbon cycle is still poorly understood. One remarkable feature is that an increasing amount of atmospheric carbon dioxide appears to be being absorbed by terrestrial vegetation. I review the recent evidence for the magnitude and spatial distribution of this 'terrestrial carbon sink', drawing on current research on the global atmospheric distribution and transport of carbon dioxide, oxygen and their isotopes; direct measurement Of CO2 fluxes above various biomes; and inventories of forest biomass and composition. I review the likely causes of these carbon sinks and sources and their implications for the ecology and stability of these biomes. Finally, I examine prospects and key issues over coming decades. Within a few years, satellite measurements of atmospheric CO2 and forest biomass, coupled with 'real-time' biosphere-atmosphere models, will revolutionize our understanding of the terrestrial carbon cycle. Controlling deforestation and managing forests has the potential to play a significant but limited part in reaching the goal of stabilizing atmospheric CO2 concentrations. However, there are likely to be limits to the amount of carbon storage possible in natural vegetation, and, in the long term, terrestrial carbon storage may be unstable, with the potential to accelerate rather than brake global warming. | |||||
BibTeX:
@article{malhi_carbon_2002, author = {Malhi, Y.}, title = {Carbon in the atmosphere and terrestrial biosphere in the 21st century}, journal = {Philosophical Transactions of the Royal Society of London Series a-Mathematical Physical and Engineering Sciences}, year = {2002}, volume = {360}, number = {1801}, pages = {2925--2945}, note = {Edition: 2003/03/11}, url = {://WOS:000180219800018 http://rsta.royalsocietypublishing.org/content/360/1801/2925.full.pdf}, doi = {https://doi.org/10.1098/rsta.2002.1098} } |
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Malhado, A.C.M., Whittaker, R.J., Malhi, Y., Ladle, R.J., ter Steege, H., Phillips, O., Aragao, L.E.O.C., Baker, T.R., Arroyo, L., Almeida, S., Higuchi, N., Killeen, T.J., Monteagudo, A., Pitman, N.C.A., Prieto, A., Salomao, R.P., Vasquez-Martinez, R., Laurance, W.F. and Ramirez-Angulo, H. | Are compound leaves an adaptation to seasonal drought or to rapid growth? Evidence from the Amazon rain forest | 2010 | Global Ecology and Biogeography Vol. 19(6), pp. 852-862 |
article | DOI URL |
Abstract: Aim To assess the hypotheses that compound leaves of trees in the Amazon forest are an adaptation to drought and/or rapid growth. Location Amazon rain forest, South America. Methods Genera from 137 permanent forest plots spread across Amazonia were classified into those with compound leaves and those with simple leaves. Metrics of compound leaf prevalence were then calculated for each plot and regression models that accounted for spatial autocorrelation were used to identify associations between climate variables and compound leaf structure. We also tested for associations between compound leaf structure and a variety of ecological variables related to life history and growth strategies, including wood density, annual increase in diameter and maximum height. Results One plant family, Fabaceae, accounts for 53% of compound-leaved individuals in the dataset, and has a geographical distribution strongly centred on north-east Amazonia. On exclusion of Fabaceae from the analysis we found no significant support for the seasonal drought hypothesis. However, we found evidence supporting the rapid growth hypothesis, with possession of compound leaves being associated with faster diameter growth rates and lower wood densities. Main conclusion This study provides evidence that possession of compound leaves constitutes one of a suite of traits and life-history strategies that promote rapid growth in rain forest trees. Our findings highlight the importance of carefully considering the geographical distribution of dominant taxa and spatial clustering of data points when inferring ecological causation from environment-trait associations. | |||||
BibTeX:
@article{malhado_are_2010, author = {Malhado, Ana C. M. and Whittaker, Robert J. and Malhi, Yadvinder and Ladle, Richard J. and ter Steege, Hans and Phillips, Oliver and Aragao, L. E. O. C. and Baker, Timothy R. and Arroyo, Luzmilla and Almeida, Samuel and Higuchi, Niro and Killeen, Tim J. and Monteagudo, Abel and Pitman, Nigel C. A. and Prieto, Adriana and Salomao, Rafael P. and Vasquez-Martinez, Rodolfo and Laurance, William F. and Ramirez-Angulo, Hirma}, title = {Are compound leaves an adaptation to seasonal drought or to rapid growth? Evidence from the Amazon rain forest}, journal = {Global Ecology and Biogeography}, year = {2010}, volume = {19}, number = {6}, pages = {852--862}, url = {://WOS:000282982300009 http://onlinelibrary.wiley.com/store/10.1111/j.1466-8238.2010.00567.x/asset/j.1466-8238.2010.00567.x.pdf?v=1&t=h6hwko37&s=2d811c2de08bb58d4c1bab270b67569776ffb21e}, doi = {https://doi.org/10.1111/j.1466-8238.2010.00567.x} } |
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Malhado, A.C.M., Whittaker, R.J., Malhi, Y., Ladle, R.J., ter Steege, H., Butt, N., Aragao, L.E.O.C., Quesada, C.A., Murakami-Araujo, A., Phillips, O.L., Peacock, J., Lopez-Gonzalez, G., Baker, T.R., Anderson, L.O., Arroyo, L., Almeida, S., Higuchi, N., Killeen, T.J., Monteagudo, A., Neill, D.A., Pitman, N.C.A., Prieto, A., Salomao, R.P., Vasquez-M, R., Laurance, W.F. and Ramirez A, H. | Spatial distribution and functional significance of leaf lamina shape in Amazonian forest trees | 2009 | Biogeosciences Vol. 6(8), pp. 1577-1590 |
article | URL |
Abstract: Leaves in tropical forests come in an enormous variety of sizes and shapes, each of which can be ultimately viewed as an adaptation to the complex problem of optimising the capture of light for photosynthesis. However, the fact that many different shape "strategies" coexist within a habitat demonstrate that there are many other intrinsic and extrinsic factors involved, such as the differential investment in support tissues required for different leaf lamina shapes. Here, we take a macrogeographic approach to understanding the function of different lamina shape categories. Specifically, we use 106 permanent plots spread across the Amazon rainforest basin to: 1) describe the geographic distribution of some simple metrics of lamina shape in plots from across Amazonia, and; 2) identify and quantify relationships between key environmental parameters and lamina shape in tropical forests. Because the plots are not randomly distributed across the study area, achieving this latter objective requires the use of statistics that can account for spatial auto-correlation. We found that between 60-70% of the 2791 species and 83 908 individual trees in the dataset could be classified as having elliptic leaves (= the widest part of the leaf is on an axis in the middle fifth of the long axis of the leaf). Furthermore, the average Amazonian tree leaf is 2.5 times longer than it is wide and has an entire margin. Contrary to theoretical expectations we found little support for the hypothesis that narrow leaves are an adaptation to dry conditions. However, we did find strong regional patterns in leaf lamina length-width ratios and several significant correlations with precipitation variables suggesting that water availability may be exerting an as yet unrecognised selective pressure on leaf shape of rainforest trees. Some support was found for the hypothesis that narrow leaves are an adaptation to low nutrient soils. Furthermore, we found a strong correlation between the proportion of trees with non-entire laminas (dissected, toothed, etc.) and mean annual temperature once again supporting the well documented association that provides a basis for reconstructing past temperature regimes. | |||||
BibTeX:
@article{malhado_spatial_2009, author = {Malhado, A. C. M. and Whittaker, R. J. and Malhi, Y. and Ladle, R. J. and ter Steege, H. and Butt, N. and Aragao, L. E. O. C. and Quesada, C. A. and Murakami-Araujo, A. and Phillips, O. L. and Peacock, J. and Lopez-Gonzalez, G. and Baker, T. R. and Anderson, L. O. and Arroyo, L. and Almeida, S. and Higuchi, N. and Killeen, T. J. and Monteagudo, A. and Neill, D. A. and Pitman, N. C. A. and Prieto, A. and Salomao, R. P. and Vasquez-M, R. and Laurance, W. F. and Ramirez A, H.}, title = {Spatial distribution and functional significance of leaf lamina shape in Amazonian forest trees}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {8}, pages = {1577--1590}, url = {://WOS:000269405000014} } |
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Malhado, A.C.M., Pires, G.F. and Costa, M.H. | Cerrado Conservation is Essential to Protect the Amazon Rainforest [BibTeX] |
2010 | Ambio Vol. 39(8), pp. 580-584 |
article | DOI URL |
BibTeX:
@article{malhado_cerrado_2010, author = {Malhado, A. C. M. and Pires, G. F. and Costa, M. H.}, title = {Cerrado Conservation is Essential to Protect the Amazon Rainforest}, journal = {Ambio}, year = {2010}, volume = {39}, number = {8}, pages = {580--584}, url = {://000283502300005 http://www.springerlink.com/content/4t145623324m1322/fulltext.pdf}, doi = {https://doi.org/10.1007/s13280-010-0084-6} } |
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Malhado, A.C.M., Malhi, Y., Whittaker, R.J., Ladle, R.J., ter Steege, H., Phillips, O.L., Butt, N., Aragao, L.E.O.C., Quesada, C.A., Araujo-Murakami, A., Arroyo, L., Peacock, J., Lopez-Gonzalez, G., Baker, T.R., Anderson, L.O., Almeida, S., Higuchi, N., Killeen, T.J., Monteagudo, A., Neill, D., Pitman, N., Prieto, A., Salomao, R.P., Vasquez-Martinez, R. and Laurance, W.F. | Spatial trends in leaf size of Amazonian rainforest trees | 2009 | Biogeosciences Vol. 6(8), pp. 1563-1576 |
article | URL |
Abstract: Leaf size influences many aspects of tree function such as rates of transpiration and photosynthesis and, consequently, often varies in a predictable way in response to environmental gradients. The recent development of pan-Amazonian databases based on permanent botanical plots has now made it possible to assess trends in leaf size across environmental gradients in Amazonia. Previous plot-based studies have shown that the community structure of Amazonian trees breaks down into at least two major ecological gradients corresponding with variations in soil fertility (decreasing from southwest to northeast) and length of the dry season (increasing from northwest to south and east). Here we describe the geographic distribution of leaf size categories based on 121 plots distributed across eight South American countries. We find that the Amazon forest is predominantly populated by tree species and individuals in the mesophyll size class (20.25-182.25 cm(2)). The geographic distribution of species and individuals with large leaves (textgreater20.25 cm(2)) is complex but is generally characterized by a higher proportion of such trees in the northwest of the region. Spatially corrected regressions reveal weak correlations between the proportion of large-leaved species and metrics of water availability. We also find a significant negative relationship between leaf size and wood density. | |||||
BibTeX:
@article{malhado_spatial_2009-1, author = {Malhado, A. C. M. and Malhi, Y. and Whittaker, R. J. and Ladle, R. J. and ter Steege, H. and Phillips, O. L. and Butt, N. and Aragao, L. E. O. C. and Quesada, C. A. and Araujo-Murakami, A. and Arroyo, L. and Peacock, J. and Lopez-Gonzalez, G. and Baker, T. R. and Anderson, L. O. and Almeida, S. and Higuchi, N. and Killeen, T. J. and Monteagudo, A. and Neill, D. and Pitman, N. and Prieto, A. and Salomao, R. P. and Vasquez-Martinez, R. and Laurance, W. F.}, title = {Spatial trends in leaf size of Amazonian rainforest trees}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {8}, pages = {1563--1576}, url = {://WOS:000269405000013} } |
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Malhado, A.C.M., Costa, M.H., de Lima, F.Z., Portilho, K.C. and Figueiredo, D.N. | Seasonal leaf dynamics in an Amazonian tropical forest | 2009 | Forest Ecology and Management Vol. 258(7), pp. 1161-1165 |
article | DOI URL |
Abstract: The ecological consequences of climate change for large tropical forests such as the Amazon are likely to be profound. Amazonian forests strongly influence regional and global climates and therefore any changes in forest structure, such as deforestation or die-back, may create positive feedback on externally forced climate change. Monitoring, modelling and managing the impacts of anthropogenic climate change on forest dynamics is therefore an important objective of forest researchers, and one that requires long-term data on changes at the level of community, populations and phenotypes. In this paper we provide the most comprehensive study yet on the seasonal dynamics of various leaf traits: leaf area index (LAI), leaf mortality (LM), leaf biomass (LB), leaf growth rate (LG), and leaf residence time (TR) from 50 experimental plots in a forest site at Belterra, Para State, Brazil. From this study we estimate annual mean leaf area index (LAI) to be 5.07 m(2) m(-2) and annual mean leaf dry biomass to be 0.621 kg m(-2). The typical leaf grew at 0.049 kg m(-2) month(-1) and remained on the tree for 12.7 months. We compare these results to other similar studies and critically discuss the factors driving leaf demographics in Amazonia. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{malhado_seasonal_2009, author = {Malhado, Ana C. M. and Costa, Marcos H. and de Lima, Francisca Z. and Portilho, Kleber C. and Figueiredo, Daniel N.}, title = {Seasonal leaf dynamics in an Amazonian tropical forest}, journal = {Forest Ecology and Management}, year = {2009}, volume = {258}, number = {7}, pages = {1161--1165}, url = {://WOS:000270152300016}, doi = {https://doi.org/10.1016/j.foreco.2009.06.002} } |
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Malavelle, F.F., Haywood, J.M., Mercado, L.M., Folberth, G.A., Bellouin, N., Sitch, S. and Artaxo, P. | Studying the impact of biomass burning aerosol radiative and climate effects on the Amazon rainforest productivity with an Earth system model [BibTeX] |
2019 | Atmospheric Chemistry And Physics Vol. 19, pp. 1301-1326 |
article | |
BibTeX:
@article{malavelle_studying_2019, author = {Malavelle, Florent F. and Haywood, Jim M. and Mercado, Lina M. and Folberth, Gerd A. and Bellouin, Nicolas and Sitch, Stephen and Artaxo, Paulo}, title = {Studying the impact of biomass burning aerosol radiative and climate effects on the Amazon rainforest productivity with an Earth system model}, journal = {Atmospheric Chemistry And Physics}, year = {2019}, volume = {19}, pages = {1301--1326} } |
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Major, J., DiTommaso, A., Lehmann, J. and Falcao, N.P.S. | Weed dynamics on Amazonian Dark Earth and adjacent soils of Brazil | 2005 | Agriculture Ecosystems & Environment Vol. 111(1-4), pp. 1-12 |
article | DOI URL |
Abstract: Field trials were conducted on Amazonian Dark Earth soils in the Manaus region, Amazonas, Brazil to assess the composition and impact of weedy vegetation on maize yield. Soil fertility among the Dark Earth varied considerably with differences largely attributable to past-use history. Consequently, maize yield and weed pressure varied among field locations, reflecting these differences in soil fertility in addition to differences in weed reservoirs such as seedbanks. Maize yield in weeded plots was as much as 63 times greater on Dark Earth (0.55 t ha(-1)) than on corresponding adjacent soil (0 t ha(-1)). and location averages varied from 0 to 3.15 t ha(-1) for Dark Earth. The percentage ground cover of weeds in weedy plots was up to 45 times greater on Dark Earth (65-99%) than on corresponding adjacent soil (2-89%), and species richness was up to I I times greater on Dark Earth (4-14 species) than corresponding adjacent soil (1-8 species). The relative proportion of annual and leguminous weeds was 32 and 17% greater, respectively, on Dark Earth than adjacent soil, and vegetative sprouting of plants was more common on sites that had been used less intensively in the past. In general, a similar weed community was observed on the different Dark Earth sites, including many species typically associated with environments that have been highly disturbed by human activities, such as Cyperus spp., Phyllantus niuri, and Croton lobatus. Seedlings from a greater number of species emerged from forested Dark Earth seedbanks (2.1 per flat) than from forested adjacent soil (1.2 per flat). The total number of emerged seedlings was greater for Dark Earth seedbanks (9.1 per flat, 1,365 m(-2)) than adjacent soil (2.2 per flat, 330 m(-2)) however the species observed were not likely to be problematic for cropping. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{major_weed_2005, author = {Major, J. and DiTommaso, A. and Lehmann, J. and Falcao, N. P. S.}, title = {Weed dynamics on Amazonian Dark Earth and adjacent soils of Brazil}, journal = {Agriculture Ecosystems & Environment}, year = {2005}, volume = {111}, number = {1-4}, pages = {1--12}, url = {://WOS:000232902200001}, doi = {https://doi.org/10.1016/j.agee.2005.04.019} } |
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Mahowald, N.M., Engelstaedter, S., Luo, C., Sealy, A., Artaxo, P., Bonnet, S., Chen, Y., Chuang, P., Cohen, D.D., Herut, B., Johansen, A.M., Kubilay, N., Losno, R., Maenhaut, W., Paytan, A., Prospero, J.M., Shank, L.M. and Siefert. R., L. | Atmospheric iron deposition: Global distribution, variability and human perturbations [BibTeX] |
2009 | Annual Review of Marine Sciences | article | DOI |
BibTeX:
@article{mahowald_atmospheric_2009, author = {Mahowald, N. M. and Engelstaedter, S. and Luo, C. and Sealy, A. and Artaxo, P. and Bonnet, S. and Chen, Y. and Chuang, P. and Cohen, D. D. and Herut, B. and Johansen, A. M. and Kubilay, N. and Losno, R. and Maenhaut, W. and Paytan, A. and Prospero, J. M. and Shank, L. M. and L., Siefert. R.}, title = {Atmospheric iron deposition: Global distribution, variability and human perturbations}, journal = {Annual Review of Marine Sciences}, year = {2009}, doi = {https://doi.org/10.1146/annurev.marine.010908.163727} } |
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Mahowald, N.M., Artaxo, P., Baker, A.R., Jickells, T.D., Okin, G.S., Randerson, J.T. and Townsend, A.R. | Impacts of biomass burning emissions and land use change on Amazonian atmospheric phosphorus cycling and deposition | 2005 | Global Biogeochemical Cycles Vol. 19(4) |
article | DOI URL |
Abstract: [1] Phosphorus ( P) availability constrains both carbon uptake and loss in some of the world's most productive ecosystems. In some of these regions, atmospheric aerosols appear to be an important, if not dominant, source of new P inputs. For example, previous work suggests that mineral aerosols from North Africa bring significant amounts of new phosphorus to the P-impoverished soils of the Amazon Basin. Here we use recent observations and atmospheric transport modeling to show that the Amazon Basin itself appears to be losing atmospheric phosphorus to neighboring regions as a consequence of biomass burning emissions, anthropogenic sources of mineral aerosols and primary biogenic particles. Observations suggest that biomass burning emissions and human disturbance are responsible for similar to 23% of the phosphorus flux in the Amazon. Although biomass burning and disturbance may bring new phosphorus into nondisturbed regions, as a whole the Amazon appears to be losing phosphorus through the atmosphere. Phosphorus lost via atmospheric transport from the Amazon is deposited in the adjacent oceans and in other regions downwind. These results suggest that land use change within the Amazon may substantially increase phosphorus availability to the remaining undisturbed forests, and that this fertilization mechanism could potentially contribute to recent changes in carbon uptake measured in undisturbed stands, as well as fertilizing downwind ocean regions. | |||||
BibTeX:
@article{mahowald_impacts_2005, author = {Mahowald, N. M. and Artaxo, P. and Baker, A. R. and Jickells, T. D. and Okin, G. S. and Randerson, J. T. and Townsend, A. R.}, title = {Impacts of biomass burning emissions and land use change on Amazonian atmospheric phosphorus cycling and deposition}, journal = {Global Biogeochemical Cycles}, year = {2005}, volume = {19}, number = {4}, url = {://WOS:000234506300002}, doi = {https://doi.org/10.1029/2005gb002541} } |
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Mahowald, N., Jickells, T., Baker, A., Artaxo, P., Benitez-Nelson, C., Bergametti, G., Bond, T.C., Chen, Y., Cohen, D., Herut, B., Kubilay, N., Losno, R., Luo, C., Maenhaut, W., McGee, K., Okin, G., Siefert, R. and Tsukuda, S. | Global distribution of atmospheric phosphorus sources, concentrations and deposition rates, and anthropogenic impacts [BibTeX] |
2008 | Global Biogeochemical Cycles Vol. 22(GB4026) |
article | DOI |
BibTeX:
@article{mahowald_global_2008, author = {Mahowald, N. and Jickells, T.D. and Baker, A.R. and Artaxo, P. and Benitez-Nelson, C.R. and Bergametti, G. and Bond, T. C. and Chen, Y. and Cohen, D.D. and Herut, B. and Kubilay, N. and Losno, R. and Luo, C. and Maenhaut, W. and McGee, K.A. and Okin, G.S. and Siefert, R.L. and Tsukuda, S.}, title = {Global distribution of atmospheric phosphorus sources, concentrations and deposition rates, and anthropogenic impacts}, journal = {Global Biogeochemical Cycles}, year = {2008}, volume = {22}, number = {GB4026}, doi = {https://doi.org/10.1029/2008GB003240} } |
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Magnusson, W.E., Sanaiotti, T.M., Lima, A.P., Martinelli, L.A., Victoria, R.L., de Araujo, M.C. and Albernaz, A.L. | A comparison of delta C-13 ratios of surface soils in savannas and forests in Amazonia | 2002 | Journal of Biogeography Vol. 29(7), pp. 857-863 |
article | DOI URL |
Abstract: Aim To determine the relationship between stable carbon isotope ratios in surface soils and the present vegetation in Amazonian savannas. Location Areas in and around savannas in the Brazilian Amazonian States of Amazonas, Para, Amapa, Roraima, Mato Grosso and Maranhao. Methods delta(13)C ratios were measured from surface (0-5 cm depth) soils in fifty-two plots in savanna plots with different covers of trees, shrubs, and grasses, and in ten adjacent areas covered by forest. Results Soil delta(13)C ratios varied widely (-24.9 to -15.2parts per thousand) among and within savannas, but were distinguishable from delta(13)C ratios under forest (-30.3 to -27.3parts per thousand). One site close to forest with 38% tree cover, 44% shrub cover and 45% grass cover was distinguishable from both forest and savanna on Landsat TM5 images, and had a delta(13)C ratio of -26.7parts per thousand. Tree density (TD), basal area (BA) and cover differed strongly between savanna and forest areas. However, most savanna areas had soil organic matter with delta(13)C ratios closer to those of forest trees than C-4 grasses. Main conclusions In Amazonia, soil delta(13)C values textgreater-25parts per thousand can be unequivocally attributed to savannas irrespective of depth. However, there is no precise relationship between tree or grass cover in savannas and surface-soil delta(13) C values. This is partly because shrubs, as well as trees and grasses, contribute significantly to soil organic matter delta(13)C ratios, and partly because there is a stronger negative relationship between area of bare ground and cover of C-4 grasses than between area of bare ground and cover of trees or shrubs. This means that the ratio of C-3 to C-4 plants tends to increase with a decrease in total cover. Areas with large amounts of open ground, may have a small proportion of grass cover relative to tree and shrub cover. Although we did not encounter any such places in this study, very harsh conditions could lead to desert-like formations with little grass cover and soil organic-matter delta(13)C ratios similar to forest areas. | |||||
BibTeX:
@article{magnusson_comparison_2002, author = {Magnusson, W. E. and Sanaiotti, T. M. and Lima, A. P. and Martinelli, L. A. and Victoria, R. L. and de Araujo, M. C. and Albernaz, A. L.}, title = {A comparison of delta C-13 ratios of surface soils in savannas and forests in Amazonia}, journal = {Journal of Biogeography}, year = {2002}, volume = {29}, number = {7}, pages = {857--863}, url = {://WOS:000177026400003}, doi = {https://doi.org/10.1046/j.1365-2699.2002.00674.x} } |
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Magnabosco Marra, D., Trumbore, S.E., Higuchi, N., Ribeiro, G.H.P.M., Negrón-Juárez, R.I., Holzwarth, F., Rifai, S.W., dos Santos, J., Lima, A.J.N., Kinupp, V.F., Chambers, J.Q. and Wirth, C. | Windthrows control biomass patterns and functional composition of Amazon forests | 2018 | Global Change Biology Vol. 24(12), pp. 5867-5881 |
article | DOI URL |
Abstract: Abstract Amazon forests account for textasciitilde25% of global land biomass and tropical tree species. In these forests, windthrows (i.e., snapped and uprooted trees) are a major natural disturbance, but the rates and mechanisms of recovery are not known. To provide a predictive framework for understanding the effects of windthrows on forest structure and functional composition (DBH ≥10 cm), we quantified biomass recovery as a function of windthrow severity (i.e., fraction of windthrow tree mortality on Landsat pixels, ranging from 0%–70%) and time since disturbance for terra-firme forests in the Central Amazon. Forest monitoring allowed insights into the processes and mechanisms driving the net biomass change (i.e., increment minus loss) and shifts in functional composition. Windthrown areas recovering for between 4–27 years had biomass stocks as low as 65.2–91.7 Mg/ha or 23%–38% of those in nearby undisturbed forests (textasciitilde255.6 Mg/ha, all sites). Even low windthrow severities (4%–20% tree mortality) caused decadal changes in biomass stocks and structure. While rates of biomass increment in recovering vegetation were nearly double (6.3 ± 1.4 Mg ha−1 year−1) those of undisturbed forests (textasciitilde3.7 Mg ha−1 year−1), biomass loss due to post-windthrow mortality was high (up to −7.5 ± 8.7 Mg ha−1 year−1, 8.5 years since disturbance) and unpredictable. Consequently, recovery to 90% of “pre-disturbance” biomass takes up to 40 years. Resprouting trees contributed little to biomass recovery. Instead, light-demanding, low-density genera (e.g., Cecropia, Inga, Miconia, Pourouma, Tachigali, and Tapirira) were favored, resulting in substantial post-windthrow species turnover. Shifts in functional composition demonstrate that windthrows affect the resilience of live tree biomass by favoring soft-wooded species with shorter life spans that are more vulnerable to future disturbances. As the time required for forests to recover biomass is likely similar to the recurrence interval of windthrows triggering succession, windthrows have the potential to control landscape biomass/carbon dynamics and functional composition in Amazon forests. | |||||
BibTeX:
@article{magnabosco_marra_windthrows_2018, author = {Magnabosco Marra, Daniel and Trumbore, Susan E. and Higuchi, Niro and Ribeiro, Gabriel H. P. M. and Negrón-Juárez, Robinson I. and Holzwarth, Frederic and Rifai, Sami W. and dos Santos, Joaquim and Lima, Adriano J. N. and Kinupp, Valdely F. and Chambers, Jeffrey Q. and Wirth, Christian}, title = {Windthrows control biomass patterns and functional composition of Amazon forests}, journal = {Global Change Biology}, year = {2018}, volume = {24}, number = {12}, pages = {5867--5881}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.14457}, doi = {https://doi.org/10.1111/gcb.14457} } |
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Magnabosco Marra, D., Lima, A.J.N., dos Santos, B.d.O., Higuchi, N. and Trumbore, S. | Radiocarbon estimates of age and growth for a dominant Amazon palm species | 2023 | Biotropica Vol. 55(1), pp. 7-12 |
article | DOI URL |
Abstract: Abstract We used destructive sampling to assess 14C-calibrated age and growth of five individuals of Oenocarpus bataua from 7.35 to 21.6 m of total height. The largest individual was 59-year-old. Age decreased from the collar to the top of the aboveground stem and was positively correlated with number of leaf-scars and height. Abstract in Portuguese is available with online material. | |||||
BibTeX:
@article{magnabosco_marra_radiocarbon_2023, author = {Magnabosco Marra, Daniel and Lima, Adriano J. N. and dos Santos, Bruna de Oliveira and Higuchi, Niro and Trumbore, Susan}, title = {Radiocarbon estimates of age and growth for a dominant Amazon palm species}, journal = {Biotropica}, year = {2023}, volume = {55}, number = {1}, pages = {7--12}, url = {https://doi.org/10.1111/btp.13156}, doi = {https://doi.org/10.1111/btp.13156} } |
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Mafra, A.C.d., Sá, L., Santos, R.M.N., Trebs, I., Sörgel M., A.C.B. and Araújo | Variabilidade da concentração média de CO2 acima da floresta Amazônica durante a noite associada a distintos regimes turbulentos [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 429-433 |
article | |
BibTeX:
@article{mafra_variabilidade_2016, author = {Mafra, A. C. de ; Sá, L. ; Santos, R. M. N. ; Trebs, I. ; Sörgel, M., A. C. B. ; Araújo}, title = {Variabilidade da concentração média de CO2 acima da floresta Amazônica durante a noite associada a distintos regimes turbulentos}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {429--433} } |
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Maenhaut, W., Fernandez-Jimenez, M.T., Rajta, I. and Artaxo, P. | Two-year study of atmospheric aerosols in Alta Floresta, Brazil: Multielemental composition and source apportionment | 2002 | Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms Vol. 189, pp. 243-248 |
article | DOI URL |
Abstract: Atmospheric aerosol samples were collected nearly continuously from August 1996 until September 1998 at Alta Floresta in a primary forest region of the Amazon basin, Brazil. The sampling device consisted of a stacked filter unit (SFU), which separates the aerosol into a coarse (2-10 mum equivalent aerodynamic diameter (EAD)) and a fine (textless2 mum EAD) size fraction. The coarse and fine filters of all SFU samples (205 in total) were analysed for the particulate mass (PM), black carbon (BC), and up to 47 elements (from Na upward). The multielemental analyses were done by a combination of PIXE and instrumental neutron activation analysis. Absolute principal component analysis was used for source (source type) identification and apportionment. Five components were identified in the fine size fraction, i.e. mineral dust, a biomass burning (pyrogenic) component (with PM, BC, S, K, Zn, Br, Rb and I, having loadings in the range 0.7-0.9), a Na/Ca component, a biogenic component (with P), and an almost pure Pb component. On average 67% of the fine PM was attributed to the pyrogenic component, 14% to the mineral dust, 7% each to the biogenic and Na/Ca components, and 4% to the Pb component. The relative contribution from the pyrogenic aerosol varied substantially with season, however. It was generally between 60% and 100% during the dry season. During the wet season, on the other hand, it often became insignificant. During that season, most of the fine aerosol was attributed to the biogenic component. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{maenhaut_two-year_2002, author = {Maenhaut, W. and Fernandez-Jimenez, M. T. and Rajta, I. and Artaxo, P.}, title = {Two-year study of atmospheric aerosols in Alta Floresta, Brazil: Multielemental composition and source apportionment}, journal = {Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms}, year = {2002}, volume = {189}, pages = {243--248}, url = {://WOS:000175595500044}, doi = {https://doi.org/10.1016/s0168-583x(01)01050-3} } |
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Maeda, E.E., Moura, Y.M., Wagner, F., Hilker, T., Lyapustin, A.I., Wang, Y., Chave, J., Mõttus, M., Aragão, L.E. and Shimabukuro, Y. | Consistency of vegetation index seasonality across the Amazon rainforest [BibTeX] |
2016 | International Journal of Applied Earth Observation and Geoinformation Vol. 52, pp. 42-53 |
article | |
BibTeX:
@article{maeda_consistency_2016, author = {Maeda, Eduardo Eiji and Moura, Yhasmin Mendes and Wagner, Fabien and Hilker, Thomas and Lyapustin, Alexei I. and Wang, Yujie and Chave, Jérôme and Mõttus, Matti and Aragão, Luiz E.O.C. and Shimabukuro, Yosio}, title = {Consistency of vegetation index seasonality across the Amazon rainforest}, journal = {International Journal of Applied Earth Observation and Geoinformation}, year = {2016}, volume = {52}, pages = {42--53} } |
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Maeda, E., Kim, H., Aragão, L., Famiglietti, J. and Oki, T. | Disruption of hydroecological equilibrium in southwest Amazon mediated by drought [BibTeX] |
2015 | Geophysical Research Letters Vol. 42(18), pp. 7546-7553 |
article | |
BibTeX:
@article{maeda_disruption_2015, author = {Maeda, EE and Kim, H and Aragão, LEOC and Famiglietti, JS and Oki, T}, title = {Disruption of hydroecological equilibrium in southwest Amazon mediated by drought}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, number = {18}, pages = {7546--7553} } |
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Machado, W., Tapajós, R., Aguiar, D., Branches, R., Martins, C. and Silva, R.d. | Influência do corte de impacto reduzido nos fluxos de energia na floresta manejada no leste da amazônia [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 410 - 413 |
article | |
BibTeX:
@article{machado_influencia_2013, author = {Machado, Wilderclay and Tapajós, Raphael and Aguiar, Diego and Branches, Rardiles and Martins, Cintya and Silva, Rodrigo da}, title = {Influência do corte de impacto reduzido nos fluxos de energia na floresta manejada no leste da amazônia}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {410 -- 413} } |
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Machado, N.G., Sanches, L., Silva, L.B., Novais, J.W.Z., Aquino, A.M., Biudes, M.S., Pinto-Junior, O.B. and Nogueira, J.S. | Soil Nutrients and Vegetation Structure in a Neotropical Seasonal Wetland [BibTeX] |
2015 | Applied Ecology and Environmental Research Vol. 13(2), pp. 289-305 |
article | |
BibTeX:
@article{machado_soil_2015, author = {Machado, N. G. and Sanches, L. and Silva, L. B. and Novais, J. W. Z. and Aquino, A. M. and Biudes, M. S. and Pinto-Junior, O. B. and Nogueira, J. S.}, title = {Soil Nutrients and Vegetation Structure in a Neotropical Seasonal Wetland}, journal = {Applied Ecology and Environmental Research}, year = {2015}, volume = {13}, number = {2}, pages = {289--305} } |
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Machado, N.G., Biudes, M.S., Angelini, L.P., Mutzenberg, D.M.d.S., Nassarden, D.C.S., Bílio, R.d.S., Silva, T.J.A., Neves, G.A.R., Arruda J. S., P.H.Z. and Nogueira | Sazonalidade do Balanço de Energia e Evapotranspiração em Área Arbustiva Alagável no Pantanal Mato-Grossense [BibTeX] |
2016 | Revista Brasileira de Meteorologia Vol. 31, pp. 82-91 |
article | |
BibTeX:
@article{machado_sazonalidade_2016, author = {Machado, Nadja Gomes and Biudes, Marcelo Sacardi and Angelini, Lucas Peres and Mutzenberg, Dalila Morgana de Souza and Nassarden, Danielle Christine Stenner and Bílio, Reinaldo de Souza and Silva, Tonny José Araújo and Neves, Geraldo Aparecido Rodrigues and Arruda, J. S., Paulo Henrique Zanella ; Nogueira}, title = {Sazonalidade do Balanço de Energia e Evapotranspiração em Área Arbustiva Alagável no Pantanal Mato-Grossense}, journal = {Revista Brasileira de Meteorologia}, year = {2016}, volume = {31}, pages = {82--91} } |
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Machado Michelazzo, P.A., Fostier, A.H., Magarelli, G., Santos, J.C. and Andrade de Carvalho Jr., J. | Mercury emissions from forest burning in southern Amazon | 2010 | Geophysical Research Letters Vol. 37(9) |
article | DOI URL |
Abstract: Several recent studies have indicated that forest fires are likely to re-emit important quantities of atmospherically deposited mercury (Hg) to the atmosphere. Although the Amazon forest accounts for approximately 25% of the world's total rainforest, few data are available about these emissions. The emissions of mercury from prescribed fires of two 4-ha plots of Amazon forest were investigated. Hg concentration and Hg burden were determined for vegetation, litter and soil before and after the fires. The data show that only Hg present in the aboveground vegetation and in the O-horizon was volatilised; no significant soil emission was observed. Before the fire, the Hg stored in the vegetation (logs, branches, leaves and litter) ranged from 3.7 to 4.0 g ha(-1) while 1.8 g ha(-1) was found in the O-horizon. The mass balance calculations of the present work indicate an average Hg emission of 3.5 g ha(-1) due to forest fires, with 1.6 ha(-1) originating from O-horizon and 1.9 from above ground vegetation. On the base of the average annual deforestation rate of the Brazilian Amazon between 2000 and 2008, an annual Hg emission of 6.7 Mg yr(-1) was estimated. Citation: Michelazzo, P. A. M., A. H. Fostier, G. Magarelli, J. C. Santos, and J. A. d. Carvalho Jr. (2010), Mercury emissions from forest burning in southern Amazon, Geophys. Res. Lett., 37, L09809, doi: 10.1029/2009GL042220. | |||||
BibTeX:
@article{machado_michelazzo_mercury_2010, author = {Machado Michelazzo, Paula Albernaz and Fostier, Anne Helene and Magarelli, Gabriella and Santos, Jose Carlos and Andrade de Carvalho, Jr., Joao}, title = {Mercury emissions from forest burning in southern Amazon}, journal = {Geophysical Research Letters}, year = {2010}, volume = {37}, number = {9}, url = {://WOS:000277705200001}, doi = {https://doi.org/10.1029/2009gl042220} } |
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Machado, L.A.T., Laurent, H. and Lima, A.A. | Diurnal march of the convection observed during TRMM-WETAMC/LBA | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Radiosonde, satellite data, Tropical Ocean-Global Atmosphere (TOGA) radar 2 km constant altitude plan position indicator (CAPPI), and rainfall collected from the TRMM-Wet Season Atmospheric Mesoscale Campaign (WETAMC)/Large-Scale Biosphere-Atmosphere (LBA) Experiment in Amazonia have been used to investigate the diurnal cycle of the tropical convection. Geostationary Operational Environmental Satellite (GOES 8) images were used to describe the diurnal modulation of the total/high/convective cloud fraction and the diurnal evolution of the size spectrum and initiation/dissipation of the convective systems. Radar 2 km CAPPI were used to describe the diurnal cycle of the rain fraction for different thresholds and the diurnal evolution of the size spectrum and initiation/dissipation of the rain cells. An average over the four rain gauge networks was applied to describe the average hourly rainfall. The upper air network data set was used to compute the thermodynamic variables: equivalent potential temperature ( e), convective available potential energy (CAPE), thickness of positive buoyancy, instability, and convective inhibition. High and convective cloud area fractions reach their maximum some hours after the maximum rainfall detected by rain gauge and radar 2 km CAPPI. The minimum cloud cover occurs only a few hours before the maximum precipitation and the maximum cloud cover occurs during the night. The maximum rainfall takes place at the time of the maximum initiation of the convective systems observed by satellite and rain cells. At the time of maximum precipitation the majority of the convective systems and rain cells are small sized and present the maximum increasing area fraction rate. The diurnal evolution of theta(e) also presents a very clear diurnal variation, with maximum occurring in the early afternoon. The CAPE is well related to theta(e). When theta(e) is high CAPE is high; the atmosphere is unstable and has a deep layer of positive buoyancy and small convective inhibition. These results suggest the following mechanism controlling the diurnal of convection: In the morning, cloud cover decreases as the solar flux reaching the surface increases and consequently increases theta(e). In the early afternoon, convection rapidly develops, high and convective cloud fractions increase rapidly, and the maximum precipitation and initiation is observed. After convection is developed the atmosphere profile is modified, reaching a nearly saturated state; the water vapor flux decreases in the boundary layer which becomes very stable, thereby inhibiting surface fluxes and consequently extinguishing the convection. | |||||
BibTeX:
@article{machado_diurnal_2002, author = {Machado, L. A. T. and Laurent, H. and Lima, A. A.}, title = {Diurnal march of the convection observed during TRMM-WETAMC/LBA}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200020}, doi = {https://doi.org/10.1029/2001jd000338} } |
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Machado, L.A.T., Laurent, H., Dessay, N. and Miranda, I. | Seasonal and diurnal variability of convection over the Amazonia: A comparison of different vegetation types and large scale forcing | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 61-77 |
article | DOI URL |
Abstract: A climatological description of the convection over Amazonia is based on the seasonal and diurnal cycle analysis. Long series of observations are used from four sites: two sites are representative of dense rainforest, either continental (Manaus) or coastal (Belem); one site is in southeast Amazonia, in a region of ecological tension where forest has been partly replaced by pasture (Vilhena); and finally, one is in the south of Amazonia, in a region typical of savanna (Brasilia). Each site has a long series of radiosonde and surface observations. Other parameters are also used: rainfall averaged from the raingauges in the vicinity of each site; vegetation monitored using NDVI averaged over 128 kmx128 km boxes centred on each site; and total and high cloud cover estimated using the 2.5degreesx2.5degrees ISCCP products derived from satellite data. It is shown that the main differences between rainforest and savanna or deforested sites occur in the dry season, whereas the magnitude and diurnal cycle of convection as well as amount of rainfall and NDVI are quite similar during the wet season. For the savanna site the seasonal variation is well defined for every parameter, whereas for rainforest sites the vegetation and atmospheric thermodynamics show very weak seasonal variations, yet driving significant diurnal variations of the convection and precipitation. The transition season from dry to wet and the beginning of the wet season is generally the period of strongest intensity of convection. | |||||
BibTeX:
@article{machado_seasonal_2004, author = {Machado, L. A. T. and Laurent, H. and Dessay, N. and Miranda, I.}, title = {Seasonal and diurnal variability of convection over the Amazonia: A comparison of different vegetation types and large scale forcing}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {61--77}, url = {://WOS:000222024700006}, doi = {https://doi.org/10.1007/s00704-004-0044-9} } |
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Machado, L.A.T. and Laurent, H. | The convective system area expansion over Amazonia and its relationships with convective system life duration and high-level wind divergence | 2004 | Monthly Weather Review Vol. 132(3), pp. 714-725 |
article | DOI URL |
Abstract: The relationships between the initial area expansion rate of tropical convective systems and their total life duration are analyzed during the period of the Wet Season Amazon Mesoscale Campaign/Large-Scale Biosphere Atmosphere (WETAMC/LBA) experiment over tropical South America, using an objective tracking of convective systems during their life cycle from infrared Geostationary Operational Environmental Satellite (GOES) images. The results show that it is possible to estimate the probable lifetime of a convective system, within certain error bars, considering only its initial area expansion. This result shows that the initial area expansion could be used as a predictor of the life cycle of convective systems. The area expansion is also a good indicator of convective activity such as the diurnal cycle of convection. Over the southwest Amazon, the maximum area expansion occurs close to the time of maximum precipitation and about 4 h before the maximum cold cloud fraction at the same threshold (235 K). Also, the hypothesis that the area expansion, and hence the convective activity, impacts the high-level wind divergence has been investigated using satellite wind observations. It is found that the wind divergence fields derived are able to describe the large-scale patterns but are not able to capture the small-scale features. The diurnal cycle of the high-level wind divergence generally shows a flat response over tropical South America, although a coherent but not significant signal is observed over the WETAMC/LBA area. It is shown that the area of the cloud shield of convective systems varies not only in association with the upper-level wind divergence but also with the condensation-evaporation process. The increase of area in this initial stage is mainly due to the condensation process. During the ensuing mature stage, the upper-air wind divergence also contributes to the expansion. | |||||
BibTeX:
@article{machado_convective_2004, author = {Machado, L. A. T. and Laurent, H.}, title = {The convective system area expansion over Amazonia and its relationships with convective system life duration and high-level wind divergence}, journal = {Monthly Weather Review}, year = {2004}, volume = {132}, number = {3}, pages = {714--725}, url = {://WOS:000220113900004}, doi = {https://doi.org/10.1175/1520-0493(2004)132%3C0714:tcsaeo%3E2.0.co;2} } |
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Machado, L.A.T., Franco, M.A., Kremper, L.A., Ditas, F., Andreae, M.O., Artaxo, P., Cecchini, M.A., Holanda, B.A., Pöhlker, M.L., Saraiva, I., Wolff, S., Pöschl, U. and Pöhlker, C. | How weather events modify aerosol particle size distributions in the Amazon boundary layer [BibTeX] |
2021 | Atmos. Chem. Phys. Vol. 21(23), pp. 18065-18086 |
article | DOI URL |
BibTeX:
@article{machado_how_2021, author = {Machado, L. A. T. and Franco, M. A. and Kremper, L. A. and Ditas, F. and Andreae, M. O. and Artaxo, P. and Cecchini, M. A. and Holanda, B. A. and Pöhlker, M. L. and Saraiva, I. and Wolff, S. and Pöschl, U. and Pöhlker, C.}, title = {How weather events modify aerosol particle size distributions in the Amazon boundary layer}, journal = {Atmos. Chem. Phys.}, year = {2021}, volume = {21}, number = {23}, pages = {18065--18086}, url = {https://acp.copernicus.org/articles/21/18065/2021/}, doi = {https://doi.org/10.5194/acp-21-18065-2021} } |
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Machado, L.A.T., Calheiros, A.J.P., Biscaro, T., Giangrande, S., Silva Dias, M.A.F. and Micael A. Cecchini Meinrat O. Andreae, W.F.A.P.A.S.B.R.B.C.B.C.W.E.J.F.Z.F.G.F.F.M.P.J.S.T.M.U.P.C.P.M.L.P.J.-F.R.D.R.J.M.B.S.C.S.R.T.D.W.and.M.W.R.A. | Overview: Precipitation Characteristics and Sensitivities to the Environmental Conditions during GoAmazon2014/5 and ACRIDICON-CHUVA [BibTeX] |
2017 | Atmos. Chem. Phys. | article | DOI |
BibTeX:
@article{machado_overview_2017, author = {Machado, Luiz A. T. and Calheiros, Alan J. P. and Biscaro, Thiago and Giangrande, Scott and Silva Dias, Maria A. F. and Micael A. Cecchini, Meinrat O. Andreae, Wagner F. Araujo, Paulo Artaxo, Stephan Bormann, Ramon Braga, Casey Burleyson, Cristiano W. Eichholz, Jiwen Fan, Zheng Feng, Gilberto F. Fisch, Michael P. Jensen, Scot T. Martin, Ulrich Pöschl, Christopher Pöhlker, Mira L., Pöhlker Jean-François Ribaud, Daniel Rosenfeld, Jaci M. B. Saraiva, Courtney Schumacher, Ryan Thalman, David Walter and Manfred Wendisch., Rachel Albrecht}, title = {Overview: Precipitation Characteristics and Sensitivities to the Environmental Conditions during GoAmazon2014/5 and ACRIDICON-CHUVA}, journal = {Atmos. Chem. Phys.}, year = {2017}, doi = {https://doi.org/10.5194/acp-2017-990} } |
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Machado, L.A.T. | The Amazon energy budget using the ABLE-2B and FluAmazon data | 2000 | Journal of the Atmospheric Sciences Vol. 57(18), pp. 3131-3144 |
article | DOI URL |
Abstract: Radiosonde and satellite data collected from the Atmosphere Boundary Layer Experiment--Wet Season and Amazon Water Vapor Flux Experiment are used to investigate the energy budget. The relationship between the cloud cover variability and the different terms of the energy budget equations was examined. The radiosonde data were used to compute the energy divergence flux for each triangle composed by three radiosonde stations. Earth Radiation Budget Experiment data were used to compute the radiative Aux in the top of the atmosphere. The cloud cover variability were computed from the International Satellite Cloud Climatology Project data. When the atmosphere undergoes a change from the mean state to the convective state, it stores energy mainly in the middle layers, while the maximum energy storage was found around 650 hPa mainly due to the perturbation of the latent energy. Conversely, when the atmosphere undergoes a change from a mean state to a nearly clear sky situation, the atmosphere column loses energy, principally due to the changes in the latent energy profile, and the atmosphere became drier, in the 700-200-hPa layer. The advective term of the energy divergence flux is of a lower order and the energy divergence flux is determined mainly from the divergent term. The profiles of the components of the energy divergence flux are essentially a result of the wind divergence weighted by the specific humidity (latent term), temperature (enthalpy term), and height (potential term). The latent energy divergence flux, for convective situations, presents a maximum in 950 hPa and is always negative (convergent) up to 400 hPa. For the nearly clear-sky situation a convergence of humidity in the lower levels and an important humidity divergence above 800 hPa were observed. The enthalpy and the latent energy divergence flux mainly describe the middle/low levels and the potential energy divergence flux represents mainly the upper troposphere. During the experiments, the solar energy absorbed by the surface was always smaller than the total surface fur supplied to the atmosphere during convective events and always larger than the total surface flux supplied to the atmosphere during nonconvective events. This means that the surface loses more energy than it receives in convective events and vice versa. The quantity of energy stored at the surface seems to be limited, defining a timescale, during which the surface needs to export or receive energy to control its deficit or gain of energy. | |||||
BibTeX:
@article{machado_amazon_2000, author = {Machado, L. A. T.}, title = {The Amazon energy budget using the ABLE-2B and FluAmazon data}, journal = {Journal of the Atmospheric Sciences}, year = {2000}, volume = {57}, number = {18}, pages = {3131--3144}, url = {://WOS:000089266700010 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%282000%29057%3C3131%3ATAEBUT%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0469(2000)057%3C3131:taebut%3E2.0.co;2} } |
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Mace, K.A., Artaxo, P. and Duce, R.A. | Water-soluble organic nitrogen in Amazon Basin aerosols during the dry (biomass burning) and wet seasons | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D16) |
article | DOI URL |
Abstract: [1] As part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), PM10 aerosol was collected during both the wet and dry (biomass burning) seasons of 1999 and analyzed for total water-soluble organic nitrogen (WSON), urea, and 17 amino acids. In addition to total WSON the inorganic N species nitrate (NO3-), nitrite (NO2-), and ammonium (NH4+) were also analyzed. WSON was found to represent similar to45% (mean concentration similar to3.5 nmol N/m(3)) and similar to43% (mean concentration similar to61 nmol N/m(3)) of the total N in wet and dry season aerosol samples, respectively. Urea and amino N made up similar to19% of the total organic N in dry season aerosols and similar to2.5% of the total organic N in wet season aerosols; the majority of WSON, similar to80% in the dry season and similar to97% in the wet season, remained uncharacterized. The results suggest that biomass burning is a source of WSON, yet poorly understood ( since this data set represents the first study of WSON in the context of biomass burning). Future studies aimed at determining the magnitude of WSON released from biomass burning globally, its species composition, and its biogeochemical significance are needed. | |||||
BibTeX:
@article{mace_water-soluble_2003, author = {Mace, K. A. and Artaxo, P. and Duce, R. A.}, title = {Water-soluble organic nitrogen in Amazon Basin aerosols during the dry (biomass burning) and wet seasons}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D16}, url = {://000185251300007}, doi = {https://doi.org/10.1029/2003jd003557} } |
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Ma, Y., Ye, J., Ribeiro, I.O., Vilà-Guerau de Arellano, J., Xin, J., Zhang, W., Souza, R.A.F.d. and Martin, S.T. | Optimization and Representativeness of Atmospheric Chemical Sampling by Hovering Unmanned Aerial Vehicles Over Tropical Forests | 2021 | Earth and Space Science Vol. 8(4), pp. e2020EA001335 |
article | DOI URL |
Abstract: Abstract Atmospheric chemical species play critical roles in ecosystem functioning and climate, but spatially resolving near-surface concentrations has been challenging. In this regard, hovering unmanned aerial vehicles (UAVs) represent an emerging technology. The study herein provides guidance for optimized atmospheric sampling by hovering copter-type UAVs. Large-eddy simulations are conducted for species having chemical lifetimes ranging from reactive (i.e., 102 s) to long-lived (i.e., 108 s). The case study of fair-weather conditions over an equatorial tropical forest is used because of previous UAV deployments in this region. A framework is developed of influence length and horizontal shift of upwind surface emissions. The framework quantifies the length scale of the contribution of upwind forest emissions to species concentrations sampled by the downwind hovering UAV. Main findings include the following: (1) sampling within an altitude that is no more than 200 m above the canopy is recommended for both high- and intermediate-reactivity species because of the strong decrease in species concentration even in a highly turbulent atmosphere; (2) sampling durations of at least 5 and 10 min are recommended for intermediate- and high-reactivity species, respectively, because of the effects of atmospheric turbulence; and (3) in the case of heterogeneity of emissions across the underlying landscape, maximum recommended altitudes are presented for horizontal sampling strategies that can resolve the variability in the landscape emissions. The coupled effects of emission rate, wind speed, species lifetime, turbulence, and UAV sampling duration on influence length must all be considered for optimized and representative sampling over forests. | |||||
BibTeX:
@article{ma_optimization_2021, author = {Ma, Yongjing and Ye, Jianhuai and Ribeiro, Igor Oliveira and Vilà-Guerau de Arellano, Jordi and Xin, Jinyuan and Zhang, Wenyu and Souza, Rodrigo Augusto Ferreira de and Martin, Scot T.}, title = {Optimization and Representativeness of Atmospheric Chemical Sampling by Hovering Unmanned Aerial Vehicles Over Tropical Forests}, journal = {Earth and Space Science}, year = {2021}, volume = {8}, number = {4}, pages = {e2020EA001335}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020EA001335}, doi = {https://doi.org/10.1029/2020EA001335} } |
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Lyra, M., L.C.B., F., Nobre, G. and R.F.F., C.A. | Some aspects of the atmospheric boundary layer over western Amazonia: dry season 1994 [BibTeX] |
2003 | Revista Brasileira de Meteorologia Vol. 18, pp. 79-85 |
article | |
BibTeX:
@article{lyra_aspects_2003, author = {Lyra, Molion, L.C.B., Fisch, G., Nobre, C.A., R.F.F.}, title = {Some aspects of the atmospheric boundary layer over western Amazonia: dry season 1994}, journal = {Revista Brasileira de Meteorologia}, year = {2003}, volume = {18}, pages = {79--85} } |
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Luyssaert, S., Inglima, I., Jung, M., Richardson, A.D., Reichsteins, M., Papale, D., Piao, S.L., Schulzes, E.D., Wingate, L., Matteucci, G., Aragao, L., Aubinet, M., Beers, C., Bernhoffer, C., Black, K.G., Bonal, D., Bonnefond, J.M., Chambers, J., Ciais, P., Cook, B., Davis, K.J., Dolman, A.J., Gielen, B., Goulden, M., Grace, J., Granier, A., Grelle, A., Griffis, T., Gruenwald, T., Guidolotti, G., Hanson, P.J., Harding, R., Hollinger, D.Y., Hutyra, L.R., Kolar, P., Kruijt, B., Kutsch, W., Lagergren, F., Laurila, T., Law, B.E., Le Maire, G., Lindroth, A., Loustau, D., Malhi, Y., Mateus, J., Migliavacca, M., Misson, L., Montagnani, L., Moncrieff, J., Moors, E., Munger, J.W., Nikinmaa, E., Ollinger, S.V., Pita, G., Rebmann, C., Roupsard, O., Saigusa, N., Sanz, M.J., Seufert, G., Sierra, C., Smith, M.L., Tang, J., Valentini, R., Vesala, T. and Janssens, I.A. | CO(2) balance of boreal, temperate, and tropical forests derived from a global database | 2007 | Global Change Biology Vol. 13(12), pp. 2509-2537 |
article | DOI URL |
Abstract: Terrestrial ecosystems sequester 2.1 Pg of atmospheric carbon annually. A large amount of the terrestrial sink is realized by forests. However, considerable uncertainties remain regarding the fate of this carbon over both short and long timescales. Relevant data to address these uncertainties are being collected at many sites around the world, but syntheses of these data are still sparse. To facilitate future synthesis activities, we have assembled a comprehensive global database for forest ecosystems, which includes carbon budget variables (fluxes and stocks), ecosystem traits (e.g. leaf area index, age), as well as ancillary site information such as management regime, climate, and soil characteristics. This publicly available database can be used to quantify global, regional or biome-specific carbon budgets; to re-examine established relationships; to test emerging hypotheses about ecosystem functioning [e.g. a constant net ecosystem production (NEP) to gross primary production (GPP) ratio]; and as benchmarks for model evaluations. In this paper, we present the first analysis of this database. We discuss the climatic influences on GPP, net primary production (NPP) and NEP and present the CO(2) balances for boreal, temperate, and tropical forest biomes based on micrometeorological, ecophysiological, and biometric flux and inventory estimates. Globally, GPP of forests benefited from higher temperatures and precipitation whereas NPP saturated above either a threshold of 1500 mm precipitation or a mean annual temperature of 10 degrees C. The global pattern in NEP was insensitive to climate and is hypothesized to be mainly determined by nonclimatic conditions such as successional stage, management, site history, and site disturbance. In all biomes, closing the CO(2) balance required the introduction of substantial biome-specific closure terms. Nonclosure was taken as an indication that respiratory processes, advection, and non-CO(2) carbon fluxes are not presently being adequately accounted for. | |||||
BibTeX:
@article{luyssaert_co2_2007, author = {Luyssaert, S. and Inglima, I. and Jung, M. and Richardson, A. D. and Reichsteins, M. and Papale, D. and Piao, S. L. and Schulzes, E. D. and Wingate, L. and Matteucci, G. and Aragao, L. and Aubinet, M. and Beers, C. and Bernhoffer, C. and Black, K. G. and Bonal, D. and Bonnefond, J. M. and Chambers, J. and Ciais, P. and Cook, B. and Davis, K. J. and Dolman, A. J. and Gielen, B. and Goulden, M. and Grace, J. and Granier, A. and Grelle, A. and Griffis, T. and Gruenwald, T. and Guidolotti, G. and Hanson, P. J. and Harding, R. and Hollinger, D. Y. and Hutyra, L. R. and Kolar, P. and Kruijt, B. and Kutsch, W. and Lagergren, F. and Laurila, T. and Law, B. E. and Le Maire, G. and Lindroth, A. and Loustau, D. and Malhi, Y. and Mateus, J. and Migliavacca, M. and Misson, L. and Montagnani, L. and Moncrieff, J. and Moors, E. and Munger, J. W. and Nikinmaa, E. and Ollinger, S. V. and Pita, G. and Rebmann, C. and Roupsard, O. and Saigusa, N. and Sanz, M. J. and Seufert, G. and Sierra, C. and Smith, M. L. and Tang, J. and Valentini, R. and Vesala, T. and Janssens, I. A.}, title = {CO(2) balance of boreal, temperate, and tropical forests derived from a global database}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {12}, pages = {2509--2537}, url = {://WOS:000251049000004 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2007.01439.x/asset/j.1365-2486.2007.01439.x.pdf?v=1&t=h6hwx74d&s=c46e0b7edcc40e329e7a50870d961e70be63a86a}, doi = {https://doi.org/10.1111/j.1365-2486.2007.01439.x} } |
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Luo, C., Mahowald, N., Bond, T., Chuang, P.Y., Artaxo, P., Siefert, R., Chen, Y. and Schauer, J. | Combustion iron distribution and deposition | 2008 | Global Biogeochemical Cycles Vol. 22(1) |
article | DOI URL |
Abstract: [1] Iron is hypothesized to be an important micronutrient for ocean biota, thus modulating carbon dioxide uptake by the ocean biological pump. Studies have assumed that atmospheric deposition of iron to the open ocean is predominantly from mineral aerosols. For the first time we model the source, transport, and deposition of iron from combustion sources. Iron is produced in small quantities during fossil fuel burning, incinerator use, and biomass burning. The sources of combustion iron are concentrated in the industrialized regions and biomass burning regions, largely in the tropics. Model results suggest that combustion iron can represent up to 50% of the total iron deposited, but over open ocean regions it is usually less than 5% of the total iron, with the highest values (textless 30%) close to the East Asian continent in the North Pacific. For ocean biogeochemistry the bioavailability of the iron is important, and this is often estimated by the fraction which is soluble ( Fe(II)). Previous studies have argued that atmospheric processing of the relatively insoluble Fe(III) occurs to make it more soluble ( Fe( II)). Modeled estimates of soluble iron amounts based solely on atmospheric processing as simulated here cannot match the variability in daily averaged in situ concentration measurements in Korea, which is located close to both combustion and dust sources. The best match to the observations is that there are substantial direct emissions of soluble iron from combustion processes. If we assume observed soluble Fe/black carbon ratios in Korea are representative of the whole globe, we obtain the result that deposition of soluble iron from combustion contributes 20-100% of the soluble iron deposition over many ocean regions. This implies that more work should be done refining the emissions and deposition of combustion sources of soluble iron globally. | |||||
BibTeX:
@article{luo_combustion_2008, author = {Luo, Chao and Mahowald, N. and Bond, T. and Chuang, P. Y. and Artaxo, P. and Siefert, R. and Chen, Y. and Schauer, J.}, title = {Combustion iron distribution and deposition}, journal = {Global Biogeochemical Cycles}, year = {2008}, volume = {22}, number = {1}, url = {://WOS:000253232700001}, doi = {https://doi.org/10.1029/2007gb002964} } |
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Luize, T., Wittmann, F., Assis, R., Venticinque EM., B. and Silva | Effects of the Flooding Gradient on Tree Community Diversity in Várzea Forests of the Purus River, Central Amazon, Brazil [BibTeX] |
2015 | Biotropica Vol. 47(2) |
article | DOI |
BibTeX:
@article{luize_effects_2015, author = {Luize, TSF; Wittmann, F; Assis, RL; Venticinque, EM., BG; Silva}, title = {Effects of the Flooding Gradient on Tree Community Diversity in Várzea Forests of the Purus River, Central Amazon, Brazil}, journal = {Biotropica}, year = {2015}, volume = {47}, number = {2}, doi = {https://doi.org/10.1111/btp.12203} } |
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Luizao, R.C., Luizao, F. and Proctor, J. | Fine root growth and nutrient release in decomposing leaf litter in three contrasting vegetation types in central Amazonia | 2007 | Plant Ecology Vol. 192(2), pp. 225-236 |
article | DOI URL |
Abstract: We tested the hypothesis that the growth of fine roots upward into the leaf litter, forming a 'surface root mat', found widely in Amazonian forests, is of adaptive value for plants of poor soils because it makes possible more rapid uptake of limiting nutrients. We assessed the effect of invasion by fine roots on the rates of loss of dry mass and nutrient content of leaf litter over 1 year in three plots in each of three contrasting forest types in central Amazonia: the stunted facies of heath forest known as campina (SHF), the taller facies of heath forest known as campinarana (THF), both on spodosols, and the surrounding lowland evergreen rain forest (LERF) on ultisol. Pairs of bags filled with freshly fallen leaves from the trees of Clitoria fairchildiana (Fabaceae) were placed on the litter layer; in order to prevent roots entering the control bag in each pair that bag was lifted from the forest floor and turned over each week, while the treatment bag was left undisturbed. From each plot, four pairs of litter bags were retrieved after 30, 60, 120, 180, 270 and 360 d, and all roots that had grown into the litterbags were carefully removed. The leaves and roots from each bag were oven-dried for nutrient analysis. In no forest type was there a significant difference in the rate of loss of dry matter from the litter between the bags with and without roots. The amounts of roots invading the litter bags increased significantly in the sequence SHF textless THF textless LERF. In no forest did the presence of roots have a significant effect on the rate of disappearance of N or P from the leaf material, or on the rate of accumulation of Fe and Al. In the SHF there was no significant effect of invasion by roots on the rates of disappearance of Ca, Mg, Mn or Zn, but in the THF, the rates of disappearance of these four elements between 270 and 360 d were significantly greater in the presence of roots. In the LERF the results were similar, but the effects of roots started earlier-the rates of disappearance of Ca and Mg were significantly enhanced between 120 and 360 d. The results from the SHF may be interpreted to suggest that the growth of fine roots (and their fungal associates) upward into leaf litter is unlikely to be explained wholly by their role in the efficient recovery of mineral nutrients. | |||||
BibTeX:
@article{luizao_fine_2007, author = {Luizao, R.C. C. and Luizao, F.J. and Proctor, J.}, title = {Fine root growth and nutrient release in decomposing leaf litter in three contrasting vegetation types in central Amazonia}, journal = {Plant Ecology}, year = {2007}, volume = {192}, number = {2}, pages = {225--236}, url = {://WOS:000249270300008}, doi = {https://doi.org/10.1007/s11258-007-9307-8} } |
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Luizao, R.C.C., Luizao, F.J., Paiva, R.Q., Monteiro, T.F., Sousa, L.S. and Kruijt, B. | Variation of carbon and nitrogen cycling processes along a topographic gradient in a central Amazonian forest | 2004 | Global Change Biology Vol. 10(5), pp. 592-600 |
article | DOI URL |
Abstract: It is well recognized in the literature that topography can influence soil nutrient stocks and dynamics in temperate regions, but for tropical forests, this source of variation has sometimes been ignored. The nature of such variations may depend upon the soil type, which in turn, is closely linked to local or regional topography. This study characterizes the soil and describes the status of carbon and nitrogen in vegetation, litterfall, litter-layer and soil upper layers along the main positions of a topographic gradient (plateau, slope and valley), 60 km north of Manaus, on Cuieiras Reserve watershed. Nitrogen concentrations in living leaves, fresh litterfall, litter-layer and soil upper layers were lower in the valley than in both slope and plateau plots. Carbon concentrations in plant material were not significantly different among the three topographic positions, resulting in higher C : N ratios in valley plots. Local topography (plateau, slope and valley) clearly was an influential factor in the nutrient distribution along the study locations. Lower rates of N cycling processes in the valley are probably related to its sandy soil texture and seasonal flooding. | |||||
BibTeX:
@article{luizao_variation_2004, author = {Luizao, R. C. C. and Luizao, F. J. and Paiva, R. Q. and Monteiro, T. F. and Sousa, L. S. and Kruijt, B.}, title = {Variation of carbon and nitrogen cycling processes along a topographic gradient in a central Amazonian forest}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {592--600}, url = {://WOS:000221421600005}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00757.x} } |
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Luizão Costa, E.&.L.F.R. | Mudanças na biomassa microbiana e nas transformações do nitrogênio do solo em uma seqüência de idades de pastagens após derruba e queima da floresta na Amazônia Central [BibTeX] |
1999 | Acta Amazonica Vol. 29, pp. 43-56 |
article | |
BibTeX:
@article{luizao_mudancas_1999, author = {Luizão, Costa, E.S. & Luizão, F.J., R.C.C.}, title = {Mudanças na biomassa microbiana e nas transformações do nitrogênio do solo em uma seqüência de idades de pastagens após derruba e queima da floresta na Amazônia Central}, journal = {Acta Amazonica}, year = {1999}, volume = {29}, pages = {43--56} } |
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Luizão, W., Costa, F., Laurance, W., Toledo, J., Vasconcelos H.L., F. and Magnusson | Impactos Antrópicos no Ecossistema de Floresta Tropical [BibTeX] |
2013 | Vol. 1Dez Anos do Programa de Pesquisas Ecológicas de Longa Duração no Brasil: Achados, Lições e Perspectivas, pp. 30-45 |
incollection | |
BibTeX:
@incollection{tabarelli_impactos_2013, author = {Luizão, W.; Costa, F.R.C.; Laurance, W.F.; Toledo, J.J.; Vasconcelos, H.L., F.J.; Magnusson}, title = {Impactos Antrópicos no Ecossistema de Floresta Tropical}, booktitle = {Dez Anos do Programa de Pesquisas Ecológicas de Longa Duração no Brasil: Achados, Lições e Perspectivas}, publisher = {Ed. Universitária da UFPE}, year = {2013}, volume = {1}, pages = {30--45} } |
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Luizao, F.J., Luizao, R.C. and Proctor, J. | Soil acidity and nutrient deficiency in central Amazonian heath forest soils | 2007 | Plant Ecology Vol. 192(2), pp. 209-224 |
article | DOI URL |
Abstract: Experiments were carried out to test the effects of liming and nutrient additions on plant growth and soil processes such as C and N mineralisation in three contrasting forest types in central Amazonia: the stunted facies of heath forest (SHF), the tall facies of heath forest (THF) and the surrounding lowland evergreen rain forest (LERF). Calcium-carbonate additions increased soil respiration in the field plots in the SHF; in laboratory incubations, soil respiration was higher in the SHF when soils were fertilised with N, and in THF and LERF after S additions. The addition of N alone or in different combinations generally induced a net immobilisation of soil N. Net nitrification increased during the incubation in SHF and THF soils fertilised with N+P, and in LERF soils fertilised with either N, or P, or CaCO3. In a field experiment using ingrowth bags, a higher fine root production was observed in all forest types when bags were fertilised with CaCl2 or CaCO3, suggesting that Ca may be a limiting nutrient in these soils. Calcium-carbonate addition in a glasshouse bioassay experiment with rice showed an overall positive effect on the survival and growth of the seedlings. In other treatments where soil pH was not raised, the rice showed acute toxicity symptoms, poor root and shoot growth and high mortality. Similar results were yielded in a field experiment, using naturally established seedlings in the field plots in SHF, THF and LERF. It is concluded that the acute H+ ion toxicity is a major growth-limiting factor for non-adapted plants in heath forest soils in central Amazonia. | |||||
BibTeX:
@article{luizao_soil_2007, author = {Luizao, F. J. and Luizao, R.C. C. and Proctor, J.}, title = {Soil acidity and nutrient deficiency in central Amazonian heath forest soils}, journal = {Plant Ecology}, year = {2007}, volume = {192}, number = {2}, pages = {209--224}, url = {://WOS:000249270300007}, doi = {https://doi.org/10.1007/s11258-007-9317-6} } |
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Luizão, F.J., Fearnside, P.M., Cerri, C.E.P. and Lehmann, J. | The Maintenance of Soil Fertility in Amazonian Managed Systems [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 311-336 |
incollection | |
BibTeX:
@incollection{m_keller_maintenance_2009, author = {Luizão, Flávio J. and Fearnside, Philip M. and Cerri, Carlos E. P. and Lehmann, Johannes}, title = {The Maintenance of Soil Fertility in Amazonian Managed Systems}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {311--336} } |
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Luizão, N., Manzi, C.A. and F.J., A.O. | Projeto LBA: Estudando as complexas interações da biosfera com a atmosfera na Amazônia [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. Fórum |
article | |
BibTeX:
@article{luizao_projeto_2005, author = {Luizão, Nobre, C.A., Manzi, A.O., F.J.}, title = {Projeto LBA: Estudando as complexas interações da biosfera com a atmosfera na Amazônia}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {Fórum} } |
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Luizão, F., Emilio, T., Martins, M., Escada, M.I., Amaral, S., Graça, P.M.A., Magnusson, W. and Nagy, L. | Pesquisa integrada na Amazônia: estado atual, desafios e perspectivas [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 177-191 |
incollection | |
BibTeX:
@incollection{emilio_pesquisa_2014, author = {Luizão, Flávio and Emilio, Thaise and Martins, Marlucia and Escada, Maria Isabel and Amaral, Silvana and Graça, Paulo Maurício Alencastro and Magnusson, William and Nagy, Laszlo}, title = {Pesquisa integrada na Amazônia: estado atual, desafios e perspectivas}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {177--191}, note = {Section: 15} } |
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Rezende, L.F.C., Randow, C.V., Ruscica, R., Sakschewski, B., Papastefanou, P., Viovy, N., Thonicke, K., Sörensson, A., Rammig, A., Cavalcanti, I.F.A. and de Castro, A.A. | Impacts of land use change and atmospheric CO2 on gross primary productivity (GPP), evaporation, and climate in southern Amazon [BibTeX] |
2022 | Journal of Geophysical Research: Atmospheres Vol. 127, pp. e2021JD034608 |
article | DOI |
BibTeX:
@article{luiz_f_c_rezende_impacts_2022, author = {Luiz F. C. Rezende, Celso Von Randow, Romina Ruscica, Boris Sakschewski, Phillip Papastefanou, Nicolas Viovy, Kirsten Thonicke, Anna Sörensson, Anja Rammig, Iracema F. A. Cavalcanti, Aline Anderson de Castro}, title = {Impacts of land use change and atmospheric CO2 on gross primary productivity (GPP), evaporation, and climate in southern Amazon}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2022}, volume = {127}, pages = {e2021JD034608}, doi = {https://doi.org/10.1029/2021JD034608} } |
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Aragão, L.E.O.C., Lima, A., Arai, E. and Anderson, L.O. | Fires in Amazonia [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 301-329 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_fires_2016, author = {Luiz E. O. C. Aragão, André Lima, Egidio Arai, Liana O. Anderson}, title = {Fires in Amazonia}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {301--329}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Lugli, L.F., Rosa, J.S., Andersen, K.M., Di Ponzio, R., Almeida, R.V., Pires, M., Cordeiro, A.L., Cunha, H.F., Martins, N.P., Assis, R.L., Moraes, A.C., Souza, S.T., Aragão, L.E., Camargo, J.L., Fuchslueger, L., Schaap, K.J., Valverde-Barrantes, O.J., Meir, P., Quesada, C.A., Mercado, L.M. and Hartley, I.P. | Rapid responses of root traits and productivity to phosphorus and cation additions in a tropical lowland forest in Amazonia | 2021 | New Phytologist Vol. 230(1), pp. 116-128 |
article | DOI URL |
Abstract: Summary Soil nutrient availability can strongly affect root traits. In tropical forests, phosphorus (P) is often considered the main limiting nutrient for plants. However, support for the P paradigm is limited, and N and cations might also control tropical forests functioning. We used a large-scale experiment to determine how the factorial addition of nitrogen (N), P and cations affected root productivity and traits related to nutrient acquisition strategies (morphological traits, phosphatase activity, arbuscular mycorrhizal colonisation and nutrient contents) in a primary rainforest growing on low-fertility soils in Central Amazonia after 1 yr of fertilisation. Multiple root traits and productivity were affected. Phosphorus additions increased annual root productivity and root diameter, but decreased root phosphatase activity. Cation additions increased root productivity at certain times of year, also increasing root diameter and mycorrhizal colonisation. P and cation additions increased their element concentrations in root tissues. No responses were detected with N addition. Here we showed that rock-derived nutrients determined root functioning in low-fertility Amazonian soils, demonstrating not only the hypothesised importance of P, but also highlighting the role of cations. The changes in fine root traits and productivity indicated that even slow-growing tropical rainforests can respond rapidly to changes in resource availability. | |||||
BibTeX:
@article{lugli_rapid_2021, author = {Lugli, Laynara F. and Rosa, Jessica S. and Andersen, Kelly M. and Di Ponzio, Raffaello and Almeida, Renata V. and Pires, Maria and Cordeiro, Amanda L. and Cunha, Hellen F.V. and Martins, Nathielly P. and Assis, Rafael L. and Moraes, Anna C.M. and Souza, Sheila T. and Aragão, Luiz E.O.C. and Camargo, Jose. L. and Fuchslueger, Lucia and Schaap, Karst J. and Valverde-Barrantes, Oscar J. and Meir, Patrick and Quesada, Carlos A. and Mercado, Lina M. and Hartley, Iain P.}, title = {Rapid responses of root traits and productivity to phosphorus and cation additions in a tropical lowland forest in Amazonia}, journal = {New Phytologist}, year = {2021}, volume = {230}, number = {1}, pages = {116--128}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.17154}, doi = {https://doi.org/10.1111/nph.17154} } |
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Lugli, L.F., Andersen, K.M., Aragão, L.E.O.C., Cordeiro, A.L., Cunha, H.F.V., Fuchslueger, L., Meir, P., Mercado, L.M., Oblitas, E., Quesada, C.A., Rosa, J.S., Schaap, K.J., Valverde-Barrantes, O. and Hartley, I.P. | Multiple phosphorus acquisition strategies adopted by fine roots in low-fertility soils in Central Amazonia | 2019 | Plant and Soil | article | DOI URL |
Abstract: Ancient Amazon soils are characterised by low concentrations of soil phosphorus (P). Therefore, it is hypothesised that plants may invest a substantial proportion of their resources belowground to adjust their P-uptake strategies, including root morphological, physiological (phosphatase enzyme activities) and biotic (arbuscular mycorrhizal (AM) associations) adaptations. Since these strategies are energy demanding, we hypothesise that trade-offs between morphological traits and root phosphatase exudation and symbiotic associations would occur. Specifically, we expected that plants which invest in finer roots, and therefore have greater ability to explore large soil volumes, would have a high investment in physiological adaptations such as enhanced phosphatase production. In contrast, we expected that plants with predominantly thicker roots would invest more in symbiotic associations, in which carbon is traded for P acquired from AM fungal communities. | |||||
BibTeX:
@article{lugli_multiple_2019, author = {Lugli, Laynara F. and Andersen, Kelly M. and Aragão, Luiz E. O. C. and Cordeiro, Amanda L. and Cunha, Hellen F. V. and Fuchslueger, Lucia and Meir, Patrick and Mercado, Lina M. and Oblitas, Erick and Quesada, Carlos A. and Rosa, Jessica S. and Schaap, Karst J. and Valverde-Barrantes, Oscar and Hartley, Iain P.}, title = {Multiple phosphorus acquisition strategies adopted by fine roots in low-fertility soils in Central Amazonia}, journal = {Plant and Soil}, year = {2019}, url = {https://doi.org/10.1007/s11104-019-03963-9}, doi = {https://doi.org/10.1007/s11104-019-03963-9} } |
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Ludewigs, T., D'Antona, A.d.O., Brondizio, E.S. and Hetrick, S. | Agrarian Structure and Land-cover Change Along the Lifespan of Three Colonization Areas in the Brazilian Amazon | 2009 | World Development Vol. 37(8), pp. 1348-1359 |
article | DOI URL |
Abstract: We analyze three aging state-led land reform projects in Amazonia, as, through time, lot turnover, consolidation, and fragmentation differentially impact the spatial composition of agrarian Structure and land use. Data include 1970-2003 satellite imagery. GIS layers, and interviews, with 640 farmers. Lot turnover rates of 72% and increases of 0.31 in Gini indexes show active land markets resulting ill intrasettlement urbanization. Deforestation rates are positively correlated with property size and cattle herd size in all Study sites, resulting in land aggregation and intrasettlement urbanization but are not related to land titles. Privatization of public lands in the Amazon re-enforces land inequality gaps instead of reducing them. Better models are needed. (C) 2009 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{ludewigs_agrarian_2009, author = {Ludewigs, Thomas and D'Antona, Alvaro de Oliveira and Brondizio, Eduardo Sonnewend and Hetrick, Scott}, title = {Agrarian Structure and Land-cover Change Along the Lifespan of Three Colonization Areas in the Brazilian Amazon}, journal = {World Development}, year = {2009}, volume = {37}, number = {8}, pages = {1348--1359}, url = {://WOS:000268435100005}, doi = {https://doi.org/10.1016/j.worlddev.2008.08.018} } |
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Lucas, J., Sheikh, P., Wittmann, F., Piedade, M., Mcgrath DG., C. and Schöngart | Effects of land-use and hydroperiod on aboveground biomass and productivity of secondary Amazonian floodplain forests [BibTeX] |
2014 | Forest Ecology and Management, Vol. 319, pp. 116-127 |
article | |
BibTeX:
@article{lucas_effects_2014, author = {Lucas, J; Sheikh, P; Wittmann, F; Piedade, MTF; Mcgrath, DG., CM; Schöngart}, title = {Effects of land-use and hydroperiod on aboveground biomass and productivity of secondary Amazonian floodplain forests}, journal = {Forest Ecology and Management,}, year = {2014}, volume = {319}, pages = {116--127} } |
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Lu, L.X., Denning, A.S., da Silva-Dias, M.A., da Silva-Dias, P., Longo, M., Freitas, S.R. and Saatchi, S. | Mesoscale circulations and atmospheric CO2 variations in the Tapajos Region, Para, Brazil | 2005 | Journal of Geophysical Research-Atmospheres Vol. 110(D21) |
article | DOI URL |
Abstract: We have investigated mesoscale circulations and atmospheric CO2 variations over a heterogeneous landscape of forests, pastures, and large rivers during the Santarem Mesoscale Campaign (SMC) of August 2001. The atmospheric CO2 concentration variations were simulated using the Colorado State University Regional Atmospheric Modeling System with four nested grids that included a 1-km finest grid centered on the Tapajos National Forest. Surface CO2 fluxes were prescribed using idealized diurnal cycles over forest and pasture that derived from flux tower observations; while surface water CO2 efflux was prescribed using a value suggested by in situ measurements in the Amazon region. Our simulation ran from 1 August through 15 August 2001, which was concurrent with the SMC. Evaluation against flux tower observations and Belterra meteorological tower measurements showed that the model captured the observed 2-m temperatures and 10-m winds reasonably well. At 57 m the model reproduced the daytime CO2 concentration better than the nighttime concentration but missed the observed early morning CO2 maxima, in part because of the difficulties of simulating stable nocturnal boundary conditions and subgrid-scale intracanopy processes. The results also suggested that the topography, the differences in roughness length between water and land, the "T'' shape juxtaposition of Amazon and Tapajos Rivers, and the resulting horizontal and vertical wind shears all facilitated the generation of local mesoscale circulations. Possible mechanisms producing a low-level convergence (LLC) line near the east bank of the Tapajos River were explored. Under strong trade wind conditions, mechanical forcing is more important than thermal forcing in LLC formation. Persistent clouds near the east side of the Tapajos River may have a significant impact on observed ecosystem carbon flux and should be taken into account if tower fluxes are to be generalized to a larger region. | |||||
BibTeX:
@article{lu_mesoscale_2005, author = {Lu, L. X. and Denning, A. S. and da Silva-Dias, M. A. and da Silva-Dias, P. and Longo, M. and Freitas, S. R. and Saatchi, S.}, title = {Mesoscale circulations and atmospheric CO2 variations in the Tapajos Region, Para, Brazil}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2005}, volume = {110}, number = {D21}, url = {://WOS:000233160600001}, doi = {https://doi.org/10.1029/2004jd005757} } |
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Lu, F., Gray, C., Bilsborrow, R.E., Mena, C.F., Erlien, C.M., Bremner, J., Barbieri, A. and Walsh, S.J. | Contrasting Colonist and Indigenous Impacts on Amazonian Forests | 2010 | Conservation Biology Vol. 24(3), pp. 881-885 |
article | DOI URL |
Abstract: To examine differences in land use and environmental impacts between colonist and indigenous populations in the northern Ecuadorian Amazon, we combined data from household surveys and remotely sensed imagery that was collected from 778 colonist households in 64 colonization sectors, and 499 households from five indigenous groups in 36 communities. Overall, measures of deforestation and forest fragmentation were significantly greater for colonists than indigenous peoples. On average, colonist households had approximately double the area in agriculture and cash crops and 5.5 times the area in pasture as indigenous households. Nevertheless, substantial variation in land-use patterns existed among the five indigenous groups in measures such as cattle ownership and use of hired agricultural labor. These findings support the potential conservation value of indigenous lands while cautioning against uniform policies that homogenize indigenous ethnic groups. | |||||
BibTeX:
@article{lu_contrasting_2010, author = {Lu, Flora and Gray, Clark and Bilsborrow, Richard E. and Mena, Carlos F. and Erlien, Christine M. and Bremner, Jason and Barbieri, Alisson and Walsh, Stephen J.}, title = {Contrasting Colonist and Indigenous Impacts on Amazonian Forests}, journal = {Conservation Biology}, year = {2010}, volume = {24}, number = {3}, pages = {881--885}, note = {Edition: 2010/03/27}, url = {://WOS:000277690900031}, doi = {https://doi.org/10.1111/j.1523-1739.2010.01463.x} } |
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Lu, D.S., Moran, E. and Batistella, M. | Linear mixture model applied to Amazonian vegetation classification | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 456-469 |
article | DOI URL |
Abstract: Many research projects require accurate delineation of different secondary succession (SS) stages over large regions/subregions of the Amazon basin. However, the complexity of vegetation stand structure, abundant vegetation species, and the smooth transition between different SS stages make vegetation classification difficult when using traditional approaches such as the maximum likelihood classifier (MLC). Most of the time, classification distinguishes only between forest/non-forest. It has been difficult to accurately distinguish stages of SS. In this paper, a linear mixture model (LMM) approach is applied to classify successional and mature forests using Thematic Mapper (TM) imagery in the Rondonia region of the Brazilian Amazon. Three endmembers (i.e., shade, soil, and green vegetation or GV) were identified based on the image itself and a constrained least-squares solution was used to unmix the image. This study indicates that the LMM approach is a promising method for distinguishing successional and mature forests in the Amazon basin using TM data. It improved vegetation classification accuracy over that of the MLC. Initial, intermediate, and advanced successional and mature forests were classified with overall accuracy of 78.2% using a threshold method on the ratio of shade to GV fractions, a 7.4% increase over the MLC. The GV and shade fractions are sensitive to the change of vegetation stand structures and better capture biophysical structure information. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{lu_linear_2003, author = {Lu, D. S. and Moran, E. and Batistella, M.}, title = {Linear mixture model applied to Amazonian vegetation classification}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {456--469}, url = {://WOS:000186827400006}, doi = {https://doi.org/10.1016/j.rse.2002.06.001} } |
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Lu, D.S., Mausel, P., Brondizio, E. and Moran, E. | Relationships between forest stand parameters and Landsat TM spectral responses in the Brazilian Amazon Basin | 2004 | Forest Ecology and Management Vol. 198(1-3), pp. 149-167 |
article | DOI URL |
Abstract: Estimation of forest stand parameters such as aboveground biomass in a large area using remotely sensed data has considerable significance for sustainable management and utility of natural resources. In practice, selecting suitable image data for such purposes remains difficult due to a poor understanding of forest stand parameters and remote-sensing spectral response relationships, particularly in moist tropical regions. This paper explores relationships between forest stand parameters and Landsat Thematic Mapper (TM) spectral responses through analyses of three study areas in the eastern Amazon basin (Altamira, Bragantina, and Ponta de Pedras). Six TM bands and many vegetation indices are examined through integration of spectral responses and field vegetation inventory data. Pearson's correlation coefficients are used to interpret relationships between forest stand parameters and TM data. This study concludes that single band TM5 and linear transformed indices such as PC1 (the first component in a principal component analysis), KT1 (brightness of the tasseled cap transform), and albedo are most strongly correlated with forest stand parameters, somewhat independent of biophysical environments. Many vegetation indices that use TM4 and TM3 data, such as the atmospherically resistant vegetation index, the atmospheric and soil vegetation index, and the normalized difference vegetation index, are weakly correlated with selected forest stand parameters. In contrast, vegetation indices using band TM5 data improve correlations with selected forest stand parameters in Altamira forests that are characterized by a complex stand structure. Forest stand structure and associated canopy shadow affect the forest stand parameters and TM spectral response relationships. This paper provides a better understanding of relationships that have a potential of being important for developing stand parameter estimation models and for improvement of vegetation classification accuracy. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{lu_relationships_2004, author = {Lu, D. S. and Mausel, P. and Brondizio, E. and Moran, E.}, title = {Relationships between forest stand parameters and Landsat TM spectral responses in the Brazilian Amazon Basin}, journal = {Forest Ecology and Management}, year = {2004}, volume = {198}, number = {1-3}, pages = {149--167}, url = {://WOS:000223410500011}, doi = {https://doi.org/10.1016/j.foreco.2004.03.048} } |
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Lu, D.S., Mausel, P., Brondizio, E. and Moran, E. | Classification of successional forest stages in the Brazilian Amazon basin | 2003 | Forest Ecology and Management Vol. 181(3), pp. 301-312 |
article | DOI URL |
Abstract: Research on secondary succession in the Amazon basin has attracted great interest in recent years. However, methods used to classify successional stages are limited. This research explores a method that can be used to differentiate regrowth stages. The vegetation inventory data were collected in Altamira, Bragantina, Pedras, and Tome-Acu of the eastern Amazon basin. A nested sampling strategy, organized by region, site, plot, and subplot, was employed for field data collection. Above-ground biomass (AGB). forest stand volume (FSV), basal area, average stand height, average stand diameter (ASD), age, ratio of tree biomass to total biomass (RTB), ratio of tree volume to total volume, and ratio of tree basal area to total basal area were calculated at the site level. Canonical discriminant analysis (CDA) was used to differentiate successional stages and to identify the best forest stand parameters to distinguish these stages. This research indicates that the CDA approach can be used to classify successional forest stages, but using RTB or a combination of two stand parameters such as AGB and ASD are more feasible and recommended in practice. (C) 2003 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{lu_classification_2003, author = {Lu, D. S. and Mausel, P. and Brondizio, E. and Moran, E.}, title = {Classification of successional forest stages in the Brazilian Amazon basin}, journal = {Forest Ecology and Management}, year = {2003}, volume = {181}, number = {3}, pages = {301--312}, url = {://WOS:000184967800003}, doi = {https://doi.org/10.1016/s0378-1127(03)00003-3} } |
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Lu, D.S., Mausel, P., Batistella, M. and Moran, E. | Comparison of land-cover classification methods in the Brazilian Amazon Basin | 2004 | Photogrammetric Engineering and Remote Sensing Vol. 70(6), pp. 723-731 |
article | URL |
Abstract: Four distinctly different classifiers were used to analyze multi-spectral data. Which of these classifiers is most suitable for a specific study area is not always clear. This paper provides a comparison of minimum-distance classifier (MDC), maximum-likelihood classifier (MLC), extraction and classification of homogeneous objects (ECHO),. and decision-tree classifier based on linear spectral mixture analysis (DTC-LSMA). Each of the classifiers used both Landsat Thematic Mapper data and identical field-based training sample datasets in a western Brazilian Amazon study area. Seven land-cover classes-mature forest, advanced secondary succession, initial secondary succession, pasture lands, agricultural lands, bare lands, and water-were classified. Classification results indicate that the DTC-LSMA and ECHO classifiers were more accurate than were the MDC and MLC. The overall accuracy of the DTC-LSMA approach was 86 percent with a 0.82 kappa coefficient and ECHO had an accuracy of 83 percent with a 0.79 kappa coefficient. The accuracy of the other classifiers ranged from 77 to 80 percent with kappa coefficients from 0.72 to 0.75. | |||||
BibTeX:
@article{lu_comparison_2004, author = {Lu, D. S. and Mausel, P. and Batistella, M. and Moran, E.}, title = {Comparison of land-cover classification methods in the Brazilian Amazon Basin}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2004}, volume = {70}, number = {6}, pages = {723--731}, url = {://WOS:000221552800009} } |
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Lu, D.S., Batistella, M. and Moran, E. | Satellite estimation of aboveground biomass and impacts of forest stand structure | 2005 | Photogrammetric Engineering and Remote Sensing Vol. 71(8), pp. 967-974 |
article | URL |
Abstract: Heterogeneous Amazonian landscapes and complex forest stand structure often make aboveground biomass (AGB) estimation difficult. In this study, spectral mixture analysis was used to convert a Landsat Thematic Mapper (TM) image into green vegetation, shade, and soil fraction images. Entropy was used to analyze the complexity of forest stand structure and to examine impacts of different stand structures on TM reflectance data. The relationships between AGB and fraction images or TM spectral signatures were investigated based on successional and primary forests, respectively, and AGB estimation models were developed for both types of forests. Our findings indicate that the AGB estimation models using fraction images perform better for successional forest biomass estimation than using TM spectral signatures. However, both models based on TM spectral signatures and fractions provided poor performance for primary forest biomass estimation. The complex stand structure and associated canopy shadow greatly reduced relationships between AGB and TM reflectance or fraction images. | |||||
BibTeX:
@article{lu_satellite_2005, author = {Lu, D. S. and Batistella, M. and Moran, E.}, title = {Satellite estimation of aboveground biomass and impacts of forest stand structure}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2005}, volume = {71}, number = {8}, pages = {967--974}, url = {://WOS:000231129700010} } |
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Lu, D.S., Batistella, M. and Moran, E. | Multitemporal spectral mixture analysis for Amazonian land-cover change detection | 2004 | Canadian Journal of Remote Sensing Vol. 30(1), pp. 87-100 |
article | URL |
Abstract: The complex landscape and environmental conditions in the moist tropical region often result in poor land-cover change detection accuracy using traditional change detection methods. This paper explores linear spectral mixture analysis (LSMA) of multitemporal thematic mapper (TM) images to detect land-cover change in Rondonia, Brazilian Amazon basin. Three image endmembers (shade, green vegetation, and soil) were developed based on a combination of field data and image scatterplots. An unconstrained least-squares solution was used to unmix the multitemporal TM images into three fractions. Then, fraction image differencing results were used to analyze land-cover change/non-change detection. The detailed "from-to" change detection was implemented using a pixel-by-pixel comparison of classified images, which were developed using a decision tree classifier on the multitemporal fraction images. This study indicates that LSMA is a powerful image processing tool for land-cover classification and change detection. The multitemporal fraction images can be effectively used for land-cover change detection. The stable and reliable multitemporal fraction images developed using LSMA make the change detection possible without the use of training sample datasets for historical remotely sensed data. This characteristic is particularly valuable for the land-cover change detection in the Amazon basin. | |||||
BibTeX:
@article{lu_multitemporal_2004, author = {Lu, D. S. and Batistella, M. and Moran, E.}, title = {Multitemporal spectral mixture analysis for Amazonian land-cover change detection}, journal = {Canadian Journal of Remote Sensing}, year = {2004}, volume = {30}, number = {1}, pages = {87--100}, url = {://WOS:000189216800011} } |
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Lu, D. and Batistella, M. | Exploring TM image texture and its relationships with biomass estimation in Rondônia, Brazilian Amazon [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 249-257 |
article | |
BibTeX:
@article{lu_exploring_2005, author = {Lu, D.P. and Batistella, M.}, title = {Exploring TM image texture and its relationships with biomass estimation in Rondônia, Brazilian Amazon}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {249--257} } |
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Lu, D., Moran, E. and Mausel, P. | Linking amazonian secondary succession forest growth to soil properties | 2002 | Land Degradation & Development Vol. 13(4), pp. 331-343 |
article | DOI URL |
Abstract: The Amazon Basin has suffered extensive deforestation in the past 30 years. Deforestation typically leads to changes in climate, biodiversity, hydrological cycle, and soil degradation. Vegetation succession plays an important role in soil restoration through accumulation of vegetation biomass and improved soil/plant interaction. However, relationships between succession and soil properties are not well known. For example, how does vegetation succession affect nutrient accumulation? Which soil factors are important in influencing vegetation growth? What is the best way to evaluate soil fertility in the Amazon basin? This paper focuses on the interrelationships between secondary succession and soil properties. Field soil sample data and vegetation inventory data were collected in two regions of Brazilian Amazonia (Altamira and Bragantina). Soil nutrients and texture were analyzed at successional forest sites. Multiple regression models were used to identify the important soil properties affecting vegetation growth, and a soil evaluation factor (SEF) was developed for evaluating soil fertility in Alfisols, Ultisols, and Oxisols, which differ in the ways they affect vegetation growth. For example, the upper 40 cm of soil is most important for vegetation growth in Alfisols, but in Ultisols and Oxisols deeper horizons significantly influence vegetation growth rates. Accumulation of vegetation biomass increased soil fertility and improved soil physical structure in Alfisols but did not completely compensate for the nutrient losses in Ultisols and Oxisols; however, it significantly reduced the rate of nutrient loss. Copyright (C) 2002 John Wiley Sons, Ltd. | |||||
BibTeX:
@article{lu_linking_2002, author = {Lu, D. and Moran, E. and Mausel, P.}, title = {Linking amazonian secondary succession forest growth to soil properties}, journal = {Land Degradation & Development}, year = {2002}, volume = {13}, number = {4}, pages = {331--343}, url = {://WOS:000177506000004}, doi = {https://doi.org/10.1002/ldr.516} } |
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Lu, D., Mausel, P., Brondizio, E. and Moran, E. | Change detection techniques | 2004 | International Journal of Remote Sensing Vol. 25(12), pp. 2365-2407 |
article | DOI URL |
Abstract: Timely and accurate change detection of Earth's surface features is extremely important for understanding relationships and interactions between human and natural phenomena in order to promote better decision making. Remote sensing data are primary sources extensively used for change detection in recent decades. Many change detection techniques have been developed. This paper summarizes and reviews these techniques. Previous literature has shown that image differencing, principal component analysis and post-classification comparison are the most common methods used for change detection. In recent years, spectral mixture analysis, artificial neural networks and integration of geographical information system and remote sensing data have become important techniques for change detection applications. Different change detection algorithms have their own merits and no single approach is optimal and applicable to all cases. In practice, different algorithms are often compared to find the best change detection results for a specific application. Research of change detection techniques is still an active topic and new techniques are needed to effectively use the increasingly diverse and complex remotely sensed data available or projected to be soon available from satellite and airborne sensors. This paper is a comprehensive exploration of all the major change detection approaches implemented as found in the literature. | |||||
BibTeX:
@article{lu_change_2004, author = {Lu, D. and Mausel, P. and Brondizio, E. and Moran, E.}, title = {Change detection techniques}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {12}, pages = {2365--2407}, url = {://WOS:000221863000009}, doi = {https://doi.org/10.1080/0143116031000139863} } |
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Lu, D., Mausel, P., Brondizio, E. and Moran, E. | Assessment of atmospheric correction methods for Landsat TM data applicable to Amazon basin LBA research | 2002 | International Journal of Remote Sensing Vol. 23(13), pp. 2651-2671 |
article | DOI URL |
Abstract: Atmospheric correction is an important preprocessing step required in many remote sensing applications. The authors are engaged in the project 'Human Dimensions of Amazonia: Forest Regeneration and Landscape Structure' in NASA/INPE's Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) programme. This project requires use of corrected Landsat TM data since research foci integrate ground-based data and TM to: (1) measure and model biomass; (2) classify Multiple stages of secondary succession; (3) model land cover/land use changes; and (4) derive spectral signatures consistent across different study areas. The 30+ scenes of TM data are historic and lack detailed atmospheric data needed by physically-based atmospheric correction models such as 6S (Second Simulation of the Satellite Signal in the Solar Spectrum). Image-based DOS models are based on image measurements and explored in this article for application to LBA study areas. Two methods using theoretical spectral radiance and image acquisition date respectively were used to convert TM DN values to at-satellite radiance. Three image-based models were employed using each method to convert at-satellite radiance to surface reflectance. Analyses of these six different image-based models were conducted. The Improved Image-based DOS was the best technique for correcting atmospheric effects in this LBA research with results similar to those obtained from physically-based approaches. | |||||
BibTeX:
@article{lu_assessment_2002, author = {Lu, D. and Mausel, P. and Brondizio, E. and Moran, E.}, title = {Assessment of atmospheric correction methods for Landsat TM data applicable to Amazon basin LBA research}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {13}, pages = {2651--2671}, url = {://WOS:000176865500007}, doi = {https://doi.org/10.1080/01431160110109642} } |
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Lu, D., Mausel, P., Batistella, M. and Moran, E. | Land-cover binary change detection methods for use in the moist tropical region of the Amazon: a comparative study | 2005 | International Journal of Remote Sensing Vol. 26(1), pp. 101-114 |
article | DOI URL |
Abstract: Many land-cover change detection techniques have been developed; however, different conclusions about the value or appropriateness of each exist. This difference of opinion is often influenced by the landscape complexity of study areas and data used for analysis. Which method is most suitable for land-cover change detection in Amazon tropical regions remains unclear. In this paper, 10 binary change detection methods were implemented and compared with respect to their capability to detect land-cover change and no change conditions in moist tropical regions. They are image differencing (ID), modified image differencing (MID), a combination of image differencing and principal component analysis (IDPCA), principal component differencing (PCD), multitemporal PCA (MPCA), change vector analysis (CVA), vegetation index differencing (VID), image ratioing (IR), modified image ratioing (MIR), and a combination of image ratioing and PCA (IRPCA). Multi-temporal Thematic Mapper (TM) data were used to conduct land-cover binary change detection. Research results indicate that MID, PCD and ID using TM band 5 are significantly better than other binary change detection methods and they are recommended specifically for implementation in the Amazon basin. | |||||
BibTeX:
@article{lu_land-cover_2005, author = {Lu, D. and Mausel, P. and Batistella, M. and Moran, E.}, title = {Land-cover binary change detection methods for use in the moist tropical region of the Amazon: a comparative study}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {1}, pages = {101--114}, url = {://WOS:000226726000008}, doi = {https://doi.org/10.1080/01431160410001720748} } |
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Lu, D., Li, G., Valladares, G.S. and Batistella, M. | Mapping soil erosion risk in Rondonia, Brazilian Amazonia: Using RULSE, remote sensing and GIS | 2004 | Land Degradation & Development Vol. 15(5), pp. 499-512 |
article | DOI URL |
Abstract: This article discusses research in which the authors applied the Revised Universal Soil Loss Equation (RUSLE), remote sensing, and geographical information system (GIS) to the maping of soil erosion risk in Brazilian Amazonia. Soil map and soil survey data were used to develop the soil erodibility factor (K), and a digital elevation model image was used to generate the topographic factor (LS). The cover-management factor (C) was developed based on vegetation, shade, and soil fraction images derived from spectral mixture analysis of a Landsat Enhanced Thematic Mapper Plus image. Assuming the same climatic conditions and no support practice in the study area, the rainfall-runoff erosivity (R) and the support practice (P) factors were not used. The majority of the study area has K values of less than 0(.)2, LS values of less than 2(.)5, and C values of less than 0(.)25. A soil erosion risk map with five classes (very low, low, medium, medium-high, and high) was produced based on the simplified RUSLE within the GIS environment, and was linked to land use and land cover (LULC) image to explore relationships between soil erosion risk and LULC distribution. The results indicate that most successional and mature forests are in very low and low erosion risk areas, while agroforestry and pasture are usually associated with medium to high risk areas. This research implies that remote sensing and GIS provide promising tools for evaluating and mapping soil erosion risk in Amazonia. Copyright (C) 2004 John Wiley Sons, Ltd. | |||||
BibTeX:
@article{lu_mapping_2004, author = {Lu, D. and Li, G. and Valladares, G. S. and Batistella, M.}, title = {Mapping soil erosion risk in Rondonia, Brazilian Amazonia: Using RULSE, remote sensing and GIS}, journal = {Land Degradation & Development}, year = {2004}, volume = {15}, number = {5}, pages = {499--512}, url = {://WOS:000224964300004}, doi = {https://doi.org/10.1002/ldr.634} } |
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Lu, D., Batistella, M., Moran, E. and Mausel, P. | Application of spectral mixture analysis to Amazonian land-use and land-cover classification | 2004 | International Journal of Remote Sensing Vol. 25(23), pp. 5345-5358 |
article | DOI URL |
Abstract: Abundant vegetation species and associated complex forest stand structures in moist tropical regions often create difficulties in accurately classifying land-use and land-cover (LULC) features. This paper examines the value of spectral mixture analysis (SMA) using Landsat Thematic Mapper (TM) data for improving LULC classification accuracy in a moist tropical area in Rondonia, Brazil. Different routines, such as constrained and unconstrained least-squares solutions, different numbers of endmembers, and minimum noise fraction transformation, were examined while implementing the SMA approach. A maximum likelihood classifier was also used to classify fraction images into seven LULC classes: mature forest, intermediate secondary succession, initial secondary succession, pasture, agricultural land, water, and bare land. The results of this study indicate that reducing correlation between image bands and using four endmembers improve classification accuracy. The overall classification accuracy was 86.6% for the seven LULC classes using the best SMA processing routine, which represents very good results for such a complex environment. The overall classification accuracy using a maximum likelihood approach was 81.4%. Another finding is that use of constrained or unconstrained solutions for unmixing the atmospherically corrected or raw Landsat TM images does not have significant influence on LULC classification performances when image endmembers are used in a SMA approach. | |||||
BibTeX:
@article{lu_application_2004, author = {Lu, D. and Batistella, M. and Moran, E. and Mausel, P.}, title = {Application of spectral mixture analysis to Amazonian land-use and land-cover classification}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {23}, pages = {5345--5358}, url = {://WOS:000225571800010}, doi = {https://doi.org/10.1080/01431160412331269733} } |
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Lu, D., Batistella, M., Moran, E. and de Miranda, E.E. | A comparative study of landsat TM and SPOT HRG images for vegetation classification in the Brazilian amazon | 2008 | Photogrammetric Engineering and Remote Sensing Vol. 74(3), pp. 311-321 |
article | URL |
Abstract: Complex forest structure and abundant tree species in the moist tropical regions often cause difficulties in classiffing vegetation classes with remotely sensed data. This paper explores improvement in vegetation classification accuracies through a comparative study of different image combinations based on the integration of Landsat Thematic Mapper (TM) and SPOT High Resolution Geometric (HRG) instrument data, as well as the combination of spectral signatures and textures. A maximum likelihood classifier was used to classify the different image combinations into thematic maps. This research indicated that data fusion based on HRG multispectral and panchromatic data slightly improved vegetation classification accuracies: a 3.1 to 4.6 percent increase in the kappa coefficient compared with the classification results based on original HRG or TM multispectral images. A combination of HRG spectral signatures and two textural images improved the kappa coefficient by 6.3 percent compared with pure HRG multispectral images. The textural images based on entropy or second-moment texture measures with a window size of 9 pixels x 9 pixels played an important role in improving vegetation classification accuracy. Overall, optical remote-sensing data are still insufficient for accurate vegetation classifications in the Amazon basin. | |||||
BibTeX:
@article{lu_comparative_2008, author = {Lu, Dengsheng and Batistella, Mateus and Moran, Emilio and de Miranda, Evaristo E.}, title = {A comparative study of landsat TM and SPOT HRG images for vegetation classification in the Brazilian amazon}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2008}, volume = {74}, number = {3}, pages = {311--321}, note = {Edition: 2008/01/01}, url = {://WOS:000253666000006} } |
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Lu, D., Batistella, M. and Moran, E. | Integration of landsat TM and SPOT HRG images for vegetation change detection in the Brazilian Amazon | 2008 | Photogrammetric Engineering and Remote Sensing Vol. 74(4), pp. 421-430 |
article | URL |
Abstract: Traditional change detection approaches have been proven to be difficult in detecting vegetation changes in the moist tropical regions with multitemporal images. This paper explores the integration of Landsat Thematic Mapper (TM) and SPOT High Resolution Geometric (HRG) instrument data for vegetation change detection in the Brazilian Amazon . A principal component analysis was used to integrate TM and HRG panchromatic data. Vegetation change/non-change was detected with the image differencing approach based on the TM and HRG fused image and the corresponding TM image. A rule-based approach was used to classify the TM and HRG multispectral images into thematic maps with three coarse land-cover classes: forest, non-forest vegetation, and non-vegetation lands. A hybrid approach combining image differencing and post-classification comparison was used to detect vegetation change trajectories. This research indicates promising vegetation change techniques, especially for vegetation gain and loss, even if very limited reference data are available. | |||||
BibTeX:
@article{lu_integration_2008, author = {Lu, Dengsheng and Batistella, Mateus and Moran, Emilio}, title = {Integration of landsat TM and SPOT HRG images for vegetation change detection in the Brazilian Amazon}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2008}, volume = {74}, number = {4}, pages = {421--430}, note = {Edition: 2008/01/01}, url = {://WOS:000254647300005} } |
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Lu, D., Batistella, M. and Moran, E. | Land-cover classification in the Brazilian Amazon with the integration of Landsat ETM plus and Radarsat data | 2007 | International Journal of Remote Sensing Vol. 28(24), pp. 5447-5459 |
article | DOI URL |
Abstract: Land-cover classification with remotely sensed data in moist tropical regions is a challenge due to the complex biophysical conditions. This paper explores techniques to improve land-cover classification accuracy through a comparative analysis of different combinations of spectral signatures and textures from Landsat Enhanced Thematic Mapper Plus (ETM +) and Radarsat data. A wavelet-merging technique was used to integrate Landsat ETM+ multispectral and panchromatic data or Radarsat data. Grey-level co-occurrence matrix (GLCM) textures based on Landsat ETM+ panchromatic or Radarsat data and different sizes of moving windows were examined. A maximum-likelihood classifier was used to implement image classification for different combinations. This research indicates the important role of textures in improving land-cover classification accuracies in Amazonian environments. The incorporation of data fusion and textures increases classification accuracy by approximately 5.8-6.9% compared to Landsat ETM+ data, but data fusion of Landsat ETM+ multispectral and panchromatic data or Radarsat data cannot effectively improve land-cover classification accuracies. | |||||
BibTeX:
@article{lu_land-cover_2007, author = {Lu, D. and Batistella, M. and Moran, E.}, title = {Land-cover classification in the Brazilian Amazon with the integration of Landsat ETM plus and Radarsat data}, journal = {International Journal of Remote Sensing}, year = {2007}, volume = {28}, number = {24}, pages = {5447--5459}, url = {://WOS:000251751600002}, doi = {https://doi.org/10.1080/01431160701227596} } |
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Lu, D., Batistella, A., Mausel, P. and Moran, E. | Mapping and monitoring land degradation risks in the Western Brazilian Amazon using multitemporal landsat TM/ETM plus images | 2007 | Land Degradation & Development Vol. 18(1), pp. 41-54 |
article | DOI URL |
Abstract: Mapping and monitoring land degradation in areas under human-induced stresses have become urgent tasks in remote sensing whose importance has not yet been fully appreciated. In this study, a surface cover index (SCI) is developed to evaluate and map potential land degradation risks associated with deforestation and accompanying soil erosion in a Western Brazilian Amazon rural settlement study area. The relationships between land-use and land-cover (LULC) types and land degradation risks as well as the impacts of LULC change on land degradation are examined. This research indicates that remotely sensed data can be effectively used for identification and mapping of land degradation risks and monitoring of land degradation changes in the study area. Sites covered by mature forest and advanced successional forests have low land degradation risk potential, while some types of initial successional forests, agroforestry/perennial agriculture and pasture have higher risk potential. Deforestation and associated soil erosion are major causes leading to land degradation, while vegetation regrowth reduces such problems. Copyright (c) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{lu_mapping_2007, author = {Lu, D. and Batistella, A. and Mausel, P. and Moran, E.}, title = {Mapping and monitoring land degradation risks in the Western Brazilian Amazon using multitemporal landsat TM/ETM plus images}, journal = {Land Degradation & Development}, year = {2007}, volume = {18}, number = {1}, pages = {41--54}, url = {://WOS:000244508000003}, doi = {https://doi.org/10.1002/ldr.762} } |
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Lu, D. | Integration of vegetation inventory data and Landsat TM image for vegetation classification in the western Brazilian Amazon | 2005 | Forest Ecology and Management Vol. 213(1-3), pp. 369-383 |
article | DOI URL |
Abstract: This paper summarizes approaches for successional forest classification and develops a new approach based on the integration of vegetation inventory data and Landsat Thematic Mapper (TM) data in Rondonia, Brazil. Entropy (ENT) is calculated using tree height distribution from field vegetation inventory data and the adjusted entropy (adjENT) is then calculated by incorporating average stand height for each sample. The adjENT estimation model is developed using a linear regression analysis based on the integration of adjENT and measured TM reflectance. The successional stages are classified based on identified thresholds of adjENT values. The results shows that three successional stages (i.e., initial, intermediate, and advanced successional stages) can be classified with user's and producer's accuracies ranging from 77% to 79% and 61 % to 89%, which are much improved comparing with the result from the maximum likelihood classifier. The strong correlation between adjENT representing forest stand structure and the TM spectral signatures may provide new insights for estimation of forest stand parameters, such as biomass, and for detection of forest degradation. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{lu_integration_2005, author = {Lu, D.}, title = {Integration of vegetation inventory data and Landsat TM image for vegetation classification in the western Brazilian Amazon}, journal = {Forest Ecology and Management}, year = {2005}, volume = {213}, number = {1-3}, pages = {369--383}, url = {://WOS:000230440200028}, doi = {https://doi.org/10.1016/j.foreco.2005.04.004} } |
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Lu, D. | Aboveground biomass estimation using Landsat TM data in the Brazilian Amazon | 2005 | International Journal of Remote Sensing Vol. 26(12), pp. 2509-2525 |
article | DOI URL |
Abstract: The complicated forest stand structure and associated abundant tree species in the Amazon often induce difficulty in estimating above ground biomass (AGB) using remotely sensed data. This paper explores AGB estimation using Landsat Thematic Mapper (TM) data in the eastern and western Brazilian Amazon, and discusses the impacts of forest stand structure on AGB estimation. Estimating AGB is still a challenging task, especially for the sites with complicated biophysical environments. The TM spectral responses are more suitable for AGB estimation in the sites with relatively simple forest stand structure than for the sites with complicated forest stand structure. Conversely, textures appear more important than spectral responses in AGB estimation in the sites with complicated forest stand structure. A combination of spectral responses and textures improves AGB estimation performance. Different study areas having various biophysical conditions affect AGB estimation performance. | |||||
BibTeX:
@article{lu_aboveground_2005, author = {Lu, D.}, title = {Aboveground biomass estimation using Landsat TM data in the Brazilian Amazon}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {12}, pages = {2509--2525}, url = {://WOS:000230731900003}, doi = {https://doi.org/10.1080/01431160500142145} } |
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Loureiro, G., Paulino, R.G. and R.S., E.J. | Análise de uma linha de instabilidade costeira na região leste do Estado do Pará [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 258-270 |
article | |
BibTeX:
@article{loureiro_alise_2006, author = {Loureiro, Gomes, R.G., Paulino, E.J., R.S.}, title = {Análise de uma linha de instabilidade costeira na região leste do Estado do Pará}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {258--270} } |
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Lorenzo, L., Perez-Harguindeguy, N., Casanoves, F. and Oliveira, A.A.d. | Recovering from forest-to-pasture conversion: leaf decomposition in Central Amazonia, Brazil [BibTeX] |
2014 | Journal of Tropical Ecology Vol. 30, pp. 93-96 |
article | DOI |
BibTeX:
@article{lorenzo_recovering_2014, author = {Lorenzo, L. and Perez-Harguindeguy, N. and Casanoves, F. and Oliveira, A. A. de}, title = {Recovering from forest-to-pasture conversion: leaf decomposition in Central Amazonia, Brazil}, journal = {Journal of Tropical Ecology}, year = {2014}, volume = {30}, pages = {93--96}, doi = {https://doi.org/10.1017/S0266467413000771} } |
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Albert, L.P., Prohaska, N., de Camargo, P.B., Huxman, T.E., Tribuzy, E.S., Ivanov, V.Y., Oliveira, R.S., Garcia, S., Smith, M.N., Junior, R.C.O., Restrepo-Coupe, N., da Silva, R., Stark, S.C., Martins, G.A., Penha, D.V., Saleska, S.R. and Wu, J. | Age-dependent leaf physiology and consequences forcrown-scale carbon uptake during the dry season in an Amazonevergreen forest [BibTeX] |
2018 | New Phytologist Vol. 219, pp. 870-884 |
article | DOI |
BibTeX:
@article{loren_p_albert_age-dependent_2018, author = {Loren P. Albert, Neill Prohaska, Plinio Barbosa de Camargo, Travis E. Huxman, Edgard S. Tribuzy, Valeriy Y. Ivanov, Rafael S. Oliveira, Sabrina Garcia, Marielle N. Smith, Raimundo Cosme Oliveira Junior, Natalia Restrepo-Coupe, Rodrigo da Silva, Scott C. Stark, Giordane A. Martins, Deliane V. Penha, Scott R. Saleska, Jin Wu}, title = {Age-dependent leaf physiology and consequences forcrown-scale carbon uptake during the dry season in an Amazonevergreen forest}, journal = {New Phytologist}, year = {2018}, volume = {219}, pages = {870--884}, doi = {https://doi.org/10.1111/nph.15056} } |
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Lopes, F., Schongart, J., Piedade MTF., A. and Wittmann | Herbáceas Aquáticas em Seis Igapós na Amazônia Central: composição e diversidade de gêneros [BibTeX] |
2014 | Revista Geográfica Acadêmica Vol. 8, pp. 5-17 |
article | |
BibTeX:
@article{lopes_herbaceas_2014, author = {Lopes, F; Schongart, J; Piedade, MTF., A; Wittmann}, title = {Herbáceas Aquáticas em Seis Igapós na Amazônia Central: composição e diversidade de gêneros}, journal = {Revista Geográfica Acadêmica}, year = {2014}, volume = {8}, pages = {5--17} } |
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Lopes, A.P., Nelson, B.W., Wu, J., Graça, P.M.L.d.A., Tavares, J.V., Prohaska, N., Martins, G.A. and Saleska, S.R. | Leaf flush drives dry season green-up of the Central Amazon [BibTeX] |
2016 | Remote Sensing of Environment Vol. 182, pp. 90-98 |
article | |
BibTeX:
@article{lopes_leaf_2016, author = {Lopes, Aline Pontes and Nelson, Bruce Walker and Wu, Jin and Graça, Paulo Maurício Lima de Alencastro and Tavares, Julia Valentim and Prohaska, Neill and Martins, Giordane Augusto and Saleska, Scott R.}, title = {Leaf flush drives dry season green-up of the Central Amazon}, journal = {Remote Sensing of Environment}, year = {2016}, volume = {182}, pages = {90--98} } |
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Lopes, A., Pantoja, P., Parolin, P., Piedade MTF., A. and Ferreira | Combined effect of elevated CO2 level and temperature on germination and initial growth of Montrichardia arborescens (L.) Schott (Araceae): a microcosm experiment [BibTeX] |
2015 | Hydrobiologia | article | DOI |
BibTeX:
@article{lopes_combined_2015, author = {Lopes, AB; Pantoja, PO; Parolin, P; Piedade, MTF., A; Ferreira}, title = {Combined effect of elevated CO2 level and temperature on germination and initial growth of Montrichardia arborescens (L.) Schott (Araceae): a microcosm experiment}, journal = {Hydrobiologia}, year = {2015}, doi = {https://doi.org/10.1007/s10750-015-2598-1} } |
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Lopes, A., Parolin, P. and Piedade, M. | Morphological and physiological traits of aquatic macrophytes respond to water chemistry in the Amazon Basin: an example of the genus Montrichardia Crueg (Araceae) [BibTeX] |
2015 | Hydrobiologia, pp. 1-15 | article | |
BibTeX:
@article{lopes_morphological_2015, author = {Lopes, A. and Parolin, P. and Piedade, MTF.}, title = {Morphological and physiological traits of aquatic macrophytes respond to water chemistry in the Amazon Basin: an example of the genus Montrichardia Crueg (Araceae)}, journal = {Hydrobiologia}, year = {2015}, pages = {1--15} } |
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Longo, M., Silva-Dias, M. and Moreira, D. | Análise das características termodinâmicas de frentes de rajadas associadas a sistemas convectivos de meso-escala em Rondônia durante a campanha do WET-AMC/LBA [BibTeX] |
2002 | Revista Brasileira de Meteorologia Vol. 107, pp. 103-112 |
article | |
BibTeX:
@article{longo_alise_2002, author = {Longo, M. and Silva-Dias, M.A.F. and Moreira, D.S.}, title = {Análise das características termodinâmicas de frentes de rajadas associadas a sistemas convectivos de meso-escala em Rondônia durante a campanha do WET-AMC/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2002}, volume = {107}, pages = {103--112} } |
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Longo, M., Knox, R.G., Levine, N.M., Alves, L.F., Bonal, D., Camargo, P.B., Fitzjarrald, D.R., Hayek, M.N., Coupe, N.R., Saleska, S.R., Silva, R.d., Stark, S.C., Tapajós, R.P., Wiedemann, K.T., Zhang, K., Wofsy, S.C. and Moorcroft, P.R. | Ecosystem heterogeneity and diversity mitigate Amazon forest resilience to frequent extreme droughts [BibTeX] |
2018 | New Phytologist | article | DOI |
BibTeX:
@article{longo_ecosystem_2018, author = {Longo, Marcos and Knox, Ryan G. and Levine, Naomi M. and Alves, Luciana F. and Bonal, Damien and Camargo, Plinio B. and Fitzjarrald, David R. and Hayek, Matthew N. and Coupe, Natalia Restrepo and Saleska, Scott R. and Silva, Rodrigo da and Stark, Scott C. and Tapajós, Raphael P. and Wiedemann, Kenia T. and Zhang, Ke and Wofsy, Steven C. and Moorcroft, Paul R.}, title = {Ecosystem heterogeneity and diversity mitigate Amazon forest resilience to frequent extreme droughts}, journal = {New Phytologist}, year = {2018}, doi = {https://doi.org/10.1111/nph.15185} } |
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Longo, K., Dos-santos, M., Leitold, M.N., Pinagé, V., Baccini, E.R., Saatchi, A., Nogueira, S., Batistella, E.M., Morton, M. and M., D.C. | Aboveground biomass variability across intact and degraded forests in the Brazilian Amazon [BibTeX] |
2016 | Global Biogeochemical Cycles Vol. 30(11), pp. p. 1639-1660 |
article | DOI |
BibTeX:
@article{longo_aboveground_2016, author = {Longo, Keller, M., Dos-santos, M.N., Leitold, V., Pinagé, E.R., Baccini, A., Saatchi, S., Nogueira, E.M., Batistella, M., Morton, D.C., M.}, title = {Aboveground biomass variability across intact and degraded forests in the Brazilian Amazon}, journal = {Global Biogeochemical Cycles}, year = {2016}, volume = {30}, number = {11}, pages = {p. 1639--1660}, doi = {https://doi.org/10.1002/2016GB005465} } |
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Longo Camargo, R.&.S.-D.M.M. | Análise das características dinâmicas e sinóticas de um evento de friagem durante a estação chuvosa na Amazônia [BibTeX] |
2004 | Revista Brasileira de Meteorologia Vol. 19, pp. 59-72 |
article | |
BibTeX:
@article{longo_alise_2004, author = {Longo, Camargo, R. & Silva-Dias, M.A.F., M.}, title = {Análise das características dinâmicas e sinóticas de um evento de friagem durante a estação chuvosa na Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2004}, volume = {19}, pages = {59--72} } |
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Longo Albrecht, R., Machado, L. and Fisch G. & Silva-Dias, M.M. | Controle de qualidade dos dados de radiossondagem da campanha WET-AMC/LBA [BibTeX] |
2002 | Revista Brasileira de Meteorologia Vol. 17, pp. 243-253 |
article | |
BibTeX:
@article{longo_controle_2002, author = {Longo, Albrecht, R.I.; Machado, L.A.; Fisch, G. & Silva-Dias, M.A.F., M.}, title = {Controle de qualidade dos dados de radiossondagem da campanha WET-AMC/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2002}, volume = {17}, pages = {243--253} } |
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Longo, K.M., Freitas, S.R., Andreae, M.O., Yokelson, R. and Artaxo, P. | Biomass Burning in Amazonia: Emissions, Long-Range Transport of Smoke and Its Regional and Remote Impacts [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 207-232 |
incollection | |
BibTeX:
@incollection{m_keller_biomass_2009, author = {Longo, K. M. and Freitas, S. R. and Andreae, M. O. and Yokelson, R. and Artaxo, P.}, title = {Biomass Burning in Amazonia: Emissions, Long-Range Transport of Smoke and Its Regional and Remote Impacts}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {207--232} } |
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Longo, K.M., Freitas, S.R., Andreae, M.O., Setzer, A., Prins, E. and Artaxo, P. | The Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) - Part 2: Model sensitivity to the biomass burning | 2010 | Atmospheric Chemistry and Physics Vol. 10(13), pp. 5785-5795 |
article | DOI URL |
Abstract: We describe an estimation technique for biomass burning emissions in South America based on a combination of remote-sensing fire products and field observations, the Brazilian Biomass Burning Emission Model (3BEM). For each fire pixel detected by remote sensing, the mass of the emitted tracer is calculated based on field observations of fire properties related to the type of vegetation burning. The burnt area is estimated from the instantaneous fire size retrieved by remote sensing, when available, or from statistical properties of the burn scars. The sources are then spatially and temporally distributed and assimilated daily by the Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) in order to perform the prognosis of related tracer concentrations. Three other biomass burning inventories, including GFEDv2 and EDGAR, are simultaneously used to compare the emission strength in terms of the resultant tracer distribution. We also assess the effect of using the daily time resolution of fire emissions by including runs with monthly-averaged emissions. We evaluate the performance of the model using the different emission estimation techniques by comparing the model results with direct measurements of carbon monoxide both near-surface and airborne, as well as remote sensing derived products. The model results obtained using the 3BEM methodology of estimation introduced in this paper show relatively good agreement with the direct measurements and MOPITT data product, suggesting the reliability of the model at local to regional scales. | |||||
BibTeX:
@article{longo_coupled_2010, author = {Longo, K. M. and Freitas, S. R. and Andreae, M. O. and Setzer, A. and Prins, E. and Artaxo, P.}, title = {The Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) - Part 2: Model sensitivity to the biomass burning}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {13}, pages = {5785--5795}, url = {://WOS:000279851400001}, doi = {https://doi.org/10.5194/acp-10-5785-2010} } |
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Logsdon, M.G., Weeks, R., Smith, M., Richey, J.E., Ballester, V. and Shimabukoro, Y. | Detection of mesoscale seasonal and interannual variation in the vegetation of the Amazon basin | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: In the Amazon basin, seasonal and interannual spectral changes measured by satellites result from anthropogenic disturbance and from the interaction between climate variation and the surface cover. Measurements of spectral change, and the characterization of that change, provide information concerning the physical processes evident at this mesoscale. A 17-yr sequence of daily Advanced Very High Resolution Radiometer (AVHRR) global area coverage (GAC) images were analyzed to produce a monthly record of surface spectral change encompassing El Nino-Southern Oscillation (ENSO) cycles. Monthly cloud-free composite images from daily AVHRR data were produced by linear filters that minimized the finescale spatial variance and allowed for a wide range analysis within a consistent mathematical framework. Here the use of a minimized local variance (MLV) filter that produced spatially smooth images in which major land-cover boundaries and spatial gradients are clearly represented is discussed. Changes in the configuration of these boundaries and the composition of the landscape elements they defined are described in terms of quantitative changes in landscape pattern. The time series produced with the MLV filter revealed a marked seasonal difference in the pattern of the landscape and structural differences over the length of the time series. Strikingly, the response of the region to drier El Nino years appears to be delayed in the MLV series, the maximum response being in the year following El Nino with little or no change seen during El Nino. | |||||
BibTeX:
@article{logsdon_detection_2005, author = {Logsdon, Miles G. and Weeks, Robin and Smith, Milton and Richey, Jeffery E. and Ballester, Victoria and Shimabukoro, Yosio}, title = {Detection of mesoscale seasonal and interannual variation in the vegetation of the Amazon basin}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241358300001} } |
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Löbs, N., Walter, D., Barbosa, C.G.G., Brill, S., Alves, R.P., Cerqueira, G.R., de Oliveira Sá, M., de Araújo, A.C., de Oliveira, L.R., Ditas, F., Moran-Zuloaga, D., Pires Florentino, A.P., Wolff, S., Godoi, R.H.M., Kesselmeier, J., Mota de Oliveira, S., Andreae, M.O., Pöhlker, C. and Weber, B. | Microclimatic conditions and water content fluctuations experienced by epiphytic bryophytes in an Amazonian rain forest [BibTeX] |
2020 | Biogeosciences Vol. 17(21), pp. 5399-5416 |
article | DOI URL |
BibTeX:
@article{lobs_microclimatic_2020, author = {Löbs, N. and Walter, D. and Barbosa, C. G. G. and Brill, S. and Alves, R. P. and Cerqueira, G. R. and de Oliveira Sá, M. and de Araújo, A. C. and de Oliveira, L. R. and Ditas, F. and Moran-Zuloaga, D. and Pires Florentino, A. P. and Wolff, S. and Godoi, R. H. M. and Kesselmeier, J. and Mota de Oliveira, S. and Andreae, M. O. and Pöhlker, C. and Weber, B.}, title = {Microclimatic conditions and water content fluctuations experienced by epiphytic bryophytes in an Amazonian rain forest}, journal = {Biogeosciences}, year = {2020}, volume = {17}, number = {21}, pages = {5399--5416}, url = {https://bg.copernicus.org/articles/17/5399/2020/}, doi = {https://doi.org/10.5194/bg-17-5399-2020} } |
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Löbs, N., Barbosa, C.G.G., Brill, S., Walter, D., Ditas, F., de Oliveira Sá, M., de Araújo, A.C., de Oliveira, L.R., Godoi, R.H.M., Wolff, S., Piepenbring, M., Kesselmeier, J., Artaxo, P., Andreae, M.O., Pöschl, U., Pöhlker, C. and Weber, B. | Aerosol measurement methods to quantify spore emissions from fungi and cryptogamic covers in the Amazon [BibTeX] |
2020 | Atmos. Meas. Tech. Vol. 13(1), pp. 153-164 |
article | DOI URL |
BibTeX:
@article{lobs_aerosol_2020, author = {Löbs, N. and Barbosa, C. G. G. and Brill, S. and Walter, D. and Ditas, F. and de Oliveira Sá, M. and de Araújo, A. C. and de Oliveira, L. R. and Godoi, R. H. M. and Wolff, S. and Piepenbring, M. and Kesselmeier, J. and Artaxo, P. and Andreae, M. O. and Pöschl, U. and Pöhlker, C. and Weber, B.}, title = {Aerosol measurement methods to quantify spore emissions from fungi and cryptogamic covers in the Amazon}, journal = {Atmos. Meas. Tech.}, year = {2020}, volume = {13}, number = {1}, pages = {153--164}, url = {https://amt.copernicus.org/articles/13/153/2020/}, doi = {https://doi.org/10.5194/amt-13-153-2020} } |
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Löbs, W., Barbosa, D., C. G. G., B., Cerqueira, S., G. R., d.O.S., de Araújo, M., A. C., d.O., L. R., D., Moran-Zuloaga, F., Pires Florentino, D., A. P., W., Godoi, S., R. H. M., K., Mota de Oliveira, J., Andreae, S., M. O., P., Weber, C. and N., B. | Microclimatic and ecophysiological conditions experienced by epiphytic bryophytes in an Amazonian rain forest [BibTeX] |
2019 | Biogeosciences Discussions Vol. 15 |
article | DOI |
BibTeX:
@article{lobs_microclimatic_2019, author = {Löbs, Walter, D., Barbosa, C. G. G., Brill, S., Cerqueira, G. R., de Oliveira Sá, M., de Araújo, A. C., de Oliveira, L. R., Ditas, F., Moran-Zuloaga, D., Pires Florentino, A. P., Wolff, S., Godoi, R. H. M., Kesselmeier, J., Mota de Oliveira, S., Andreae, M. O., Pöhlker, C., Weber, B., N.}, title = {Microclimatic and ecophysiological conditions experienced by epiphytic bryophytes in an Amazonian rain forest}, journal = {Biogeosciences Discussions}, year = {2019}, volume = {15}, doi = {https://doi.org/10.5194/bg-2018-521} } |
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Loarie, S.R., Asner, G.P. and Field, C.B. | Boosted carbon emissions from Amazon deforestation | 2009 | Geophysical Research Letters Vol. 36 |
article | DOI URL |
Abstract: Standing biomass is a major, often poorly quantified determinate of carbon losses from land clearing. We analyzed maps from the 2001-2007 PRODES deforestation time series with recent regional pre-deforestation aboveground biomass estimates to calculate carbon emission trends for the Brazilian Amazon basin. Although the annual rate of deforestation has not changed significantly since the 1990s ( ANOVA, p = 0.3), the aboveground biomass lost per unit of forest cleared increased from 2001 to 2007 ( 183 to 201 Mg C ha(-1); slope of regression significant: p textless 0.01). Remaining unprotected forests harbor significantly higher aboveground biomass still, averaging 231 Mg C ha(-1). This difference is large enough that, even if the annual area deforested remains unchanged, future clearing will increase regional emissions by similar to 0.04 Pg C yr(-1) - a similar to 25% increase over 2001 - 2007 annual carbon emissions. These results suggest increased climate risk from future deforestation, but highlight opportunities through reductions in deforestation and forest degradation ( REDD). Citation: Loarie, S. R., G. P. Asner, and C. B. Field ( 2009), Boosted carbon emissions from Amazon deforestation, Geophys. Res. Lett., 36, L14810, doi:10.1029/2009GL037526. | |||||
BibTeX:
@article{loarie_boosted_2009, author = {Loarie, Scott R. and Asner, Gregory P. and Field, Christopher B.}, title = {Boosted carbon emissions from Amazon deforestation}, journal = {Geophysical Research Letters}, year = {2009}, volume = {36}, url = {://WOS:000268349500002 http://www.agu.org/pubs/crossref/2009/2009GL037526.shtml}, doi = {https://doi.org/10.1029/2009gl037526} } |
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Lloyd, J., Patino, S., Paiva, R.Q., Nardoto, G.B., Quesada, C.A., Santos, A.J.B., Baker, T.R., Brand, W.A., Hilke, I., Gielmann, H., Raessler, M., Luizao, F.J., Martinelli, L.A. and Mercado, L.M. | Optimisation of photosynthetic carbon gain and within-canopy gradients of associated foliar traits for Amazon forest trees | 2010 | Biogeosciences Vol. 7(6), pp. 1833-1859 |
article | DOI URL |
Abstract: Vertical profiles in leaf mass per unit leaf area (M(A)), foliar (13)C composition (delta(13)C), nitrogen (N), phosphorus (P), carbon (C) and major cation concentrations were estimated for 204 rain forest trees growing in 57 sites across the Amazon Basin. Data was analysed using a multilevel modelling approach, allowing a separation of gradients within individual tree canopies (within-tree gradients) as opposed to stand level gradients occurring because of systematic differences occurring between different trees of different heights (between-tree gradients). Significant positive within-tree gradients (i.e. increasing values with increasing sampling height) were observed for M(A) and [C](DW) (the subscript denoting on a dry weight basis) with negative within-tree gradients observed for delta(13)C, [Mg](DW) and [K](DW). No significant within-tree gradients were observed for [N](DW), [P](DW) or [Ca](DW). The magnitudes of between-tree gradients were not significantly different to the within-tree gradients for M(A), delta(13)C, [C](DW), [K](DW), [N](DW), [P](DW) and [Ca](DW). But for [Mg](DW), although there was no systematic difference observed between trees of different heights, strongly negative within-tree gradients were found to occur. When expressed on a leaf area basis (denoted by the subscript 'A'), significant positive gradients were observed for [N](A), [P](A) and [K](A) both within and between trees, these being attributable to the positive intra- and between-tree gradients in M(A) mentioned above. No systematic within-tree gradient was observed for either [Ca](A) or [Mg](A), but with a significant positive gradient observed for [Mg](A) between trees (i.e. with taller trees tending to have a higher Mg per unit leaf area). Significant differences in within-tree gradients between individuals were observed only for M(A), delta(13)C and [P] (A). This was best associated with the overall average [P](A) for each tree, this also being considered to be a surrogate for a tree's average leaf area based photosynthetic capacity, A(max). A new model is presented which is in agreement with the above observations. The model predicts that trees characterised by a low upper canopy A(max) should have shallow, or even non-existent, within-canopy gradients in A(max), with optimal intra-canopy gradients becoming sharper as a tree's upper canopy A(max) increases. Nevertheless, in all cases it is predicted that the optimal within-canopy gradient in A(max) should be substantially less than for photon irradiance. Although this is also shown to be consistent with numerous observations as illustrated by a literature survey of gradients in photosynthetic capacity for broadleaf trees, it is also in contrast to previously held notions of optimality. A new equation relating gradients in photosynthetic capacity within broadleaf tree canopies to the photosynthetic capacity of their upper canopy leaves is presented. | |||||
BibTeX:
@article{lloyd_optimisation_2010, author = {Lloyd, J. and Patino, S. and Paiva, R. Q. and Nardoto, G. B. and Quesada, C. A. and Santos, A. J. B. and Baker, T. R. and Brand, W. A. and Hilke, I. and Gielmann, H. and Raessler, M. and Luizao, F. J. and Martinelli, L. A. and Mercado, L. M.}, title = {Optimisation of photosynthetic carbon gain and within-canopy gradients of associated foliar traits for Amazon forest trees}, journal = {Biogeosciences}, year = {2010}, volume = {7}, number = {6}, pages = {1833--1859}, url = {://WOS:000279390700002}, doi = {https://doi.org/10.5194/bg-7-1833-2010} } |
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Lloyd, J., Kolle, O., Fritsch, H., de Freitas, S.R., Dias, M.A.F.S., Artaxo, P., Nobre, A.D., de Araujo, A.C., Kruijt, B., Sogacheva, L., Fisch, G., Thielmann, A., Kuhn, U. and Andreae, M.O. | An airborne regional carbon balance for Central Amazonia | 2007 | Biogeosciences Vol. 4(5), pp. 759-768 |
article | URL |
Abstract: We obtained regional estimates of surface CO textless sub textgreater 2 textless/sub textgreater exchange rates using atmospheric boundary layer budgeting techniques above tropical forest near Manaus, Brazil. Comparisons were made with simultaneous measurements from two eddy covariance towers below. Although there was good agreement for daytime measurements, large differences emerged for integrating periods dominated by the night-time fluxes. These results suggest that a systematic underestimation of night time respiratory effluxes may be responsible for the high Amazonian carbon sink suggested by several previous eddy covariance studies. Large CO(2) fluxes from riverine sources or high respiratory losses from recently disturbed forests do not need to be invoked in order to balance the carbon budget of the Amazon. Our results do not, however, discount some contribution of these processes to the overall Amazon carbon budget. | |||||
BibTeX:
@article{lloyd_airborne_2007, author = {Lloyd, J. and Kolle, O. and Fritsch, H. and de Freitas, S. R. and Dias, M. A. F. Silva and Artaxo, P. and Nobre, A. D. and de Araujo, A. C. and Kruijt, B. and Sogacheva, L. and Fisch, G. and Thielmann, A. and Kuhn, U. and Andreae, M. O.}, title = {An airborne regional carbon balance for Central Amazonia}, journal = {Biogeosciences}, year = {2007}, volume = {4}, number = {5}, pages = {759--768}, url = {://WOS:000250553900005} } |
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Lloyd, J., Goulden, M.L., Ometto, J.P., Patiño, S., Fyllas, N.M. and Quesada, C.A. | Ecophysiology of Forest and Savanna Vegetation [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 463-484 |
incollection | |
BibTeX:
@incollection{m_keller_ecophysiology_2009, author = {Lloyd, J. and Goulden, M. L. and Ometto, J. P. and Patiño, S. and Fyllas, N. M. and Quesada, C. A.}, title = {Ecophysiology of Forest and Savanna Vegetation}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {463--484} } |
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Lloyd, J., Gloor, E.U. and Lewis, S.L. | Are the dynamics of tropical forests dominated by large and rare disturbance events? | 2009 | Ecology Letters Vol. 12(12), pp. E19-E21 |
article | DOI URL |
Abstract: A recent Ecology Letters paper of Fisher et al. (2008) utilized a modelling framework to investigate disturbance effects on forest biomass dynamics. But it contains serious methodological and conceptual errors. Associated conclusions are unlikely to be correct. | |||||
BibTeX:
@article{lloyd_are_2009, author = {Lloyd, Jon and Gloor, Emanuel U. and Lewis, Simon L.}, title = {Are the dynamics of tropical forests dominated by large and rare disturbance events?}, journal = {Ecology Letters}, year = {2009}, volume = {12}, number = {12}, pages = {E19--E21}, note = {Edition: 2009/11/26}, url = {://WOS:000271631500001 http://onlinelibrary.wiley.com/store/10.1111/j.1461-0248.2009.01326.x/asset/j.1461-0248.2009.01326.x.pdf?v=1&t=h6hwkxjp&s=ef704709f22a406ee02e9a7c168464d0f78480e0}, doi = {https://doi.org/10.1111/j.1461-0248.2009.01326.x} } |
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Lloyd, J. and Farquhar, G.D. | Effects of rising temperatures and CO2 on the physiology of tropical forest trees | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1811-1817 |
article | DOI URL |
Abstract: Using a mixture of observations and climate model outputs and a simple parametrization of leaf-level photosynthesis incorporating known temperature sensitivities, we find no evidence for tropical forests currently existing 'dangerously close' to their optimum temperature range. Our model suggests that although reductions in photosynthetic rate at leaf temperatures (T-L) above 30 degrees C may occur, these are almost entirely accountable for in terms of reductions in stomatal conductance in response to higher leaf-to-air vapour pressure deficits D. This is as opposed to direct effects of T-L on photosynthetic metabolism. We also find that increases in photosynthetic rates associated with increases in ambient [CO2] over forthcoming decades should more than offset any decline in photosynthetic productivity due to higher D or T-L or increased autotrophic respiration rates as a consequence of higher tissue temperatures. We also find little direct evidence that tropical forests should not be able to respond to increases in [CO2] and argue that the magnitude and pattern of increases in forest dynamics across Amazonia observed over the last few decades are consistent with a [CO2]-induced stimulation of tree growth. | |||||
BibTeX:
@article{lloyd_effects_2008, author = {Lloyd, Jon and Farquhar, Graham D.}, title = {Effects of rising temperatures and CO2 on the physiology of tropical forest trees}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1811--1817}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500013}, doi = {https://doi.org/10.1098/rstb.2007.0032} } |
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Llopart, M., da Rocha, R., Reboita, M. and al. , e. | Sensitivity of simulated South America climate to the land surface schemes in RegCM4 [BibTeX] |
2017 | Climate Dynamics, pp. 1-13 | article | DOI |
BibTeX:
@article{llopart_sensitivity_2017, author = {Llopart, M. and da Rocha, R.P. and Reboita, M. and al., et}, title = {Sensitivity of simulated South America climate to the land surface schemes in RegCM4}, journal = {Climate Dynamics}, year = {2017}, pages = {1--13}, doi = {https://doi.org/10.1007/s00382-017-3557-5} } |
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Llopart, M., Coppola, E., Giorgi, F., da Rocha, R. and Cuadra, S. | Climate change impact on precipitation for the Amazon and La Plata basins [BibTeX] |
2014 | Climatic Change Vol. 125(1), pp. 111-125 |
article | |
BibTeX:
@article{llopart_climate_2014, author = {Llopart, M. and Coppola, E. and Giorgi, F. and da Rocha, R.P. and Cuadra, S.V.}, title = {Climate change impact on precipitation for the Amazon and La Plata basins}, journal = {Climatic Change}, year = {2014}, volume = {125}, number = {1}, pages = {111--125} } |
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Liu, Y., Su, H., Wang, S., Wei, C., Tao, W., Pöhlker, M.L., Pöhlker, C., Holanda, B.A., Krüger, O.O., Hoffmann, T., Wendisch, M., Artaxo, P., Pöschl, U., Andreae, M.O. and Cheng, Y. | Strong particle production and condensational growth in the upper troposphere sustained by biogenic VOCs from the canopy of the Amazon Basin [BibTeX] |
2023 | Atmos. Chem. Phys. Vol. 23(1), pp. 251-272 |
article | DOI URL |
BibTeX:
@article{liu_strong_2023, author = {Liu, Y. and Su, H. and Wang, S. and Wei, C. and Tao, W. and Pöhlker, M. L. and Pöhlker, C. and Holanda, B. A. and Krüger, O. O. and Hoffmann, T. and Wendisch, M. and Artaxo, P. and Pöschl, U. and Andreae, M. O. and Cheng, Y.}, title = {Strong particle production and condensational growth in the upper troposphere sustained by biogenic VOCs from the canopy of the Amazon Basin}, journal = {Atmos. Chem. Phys.}, year = {2023}, volume = {23}, number = {1}, pages = {251--272}, url = {https://acp.copernicus.org/articles/23/251/2023/}, doi = {https://doi.org/10.5194/acp-23-251-2023} } |
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Liu, Y., Su, H., Wang, S., Wei, C., Tao, W., Pöhlker, M.L., Pöhlker, C., Holanda, B.A., Krüger, O.O., Hoffmann, T., Wendisch, M., Artaxo, P., Pöschl, U., Andreae, M.O. and Cheng, Y. | Strong particle production and condensational growth in the upper troposphere sustained by biogenic VOCs from the canopy of the Amazon Basin [BibTeX] |
2022 | Atmos. Chem. Phys. Discuss. Vol. 2022, pp. 1-34 |
article | DOI URL |
BibTeX:
@article{liu_strong_2022, author = {Liu, Y. and Su, H. and Wang, S. and Wei, C. and Tao, W. and Pöhlker, M. L. and Pöhlker, C. and Holanda, B. A. and Krüger, O. O. and Hoffmann, T. and Wendisch, M. and Artaxo, P. and Pöschl, U. and Andreae, M. O. and Cheng, Y.}, title = {Strong particle production and condensational growth in the upper troposphere sustained by biogenic VOCs from the canopy of the Amazon Basin}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2022}, volume = {2022}, pages = {1--34}, url = {https://acp.copernicus.org/preprints/acp-2022-530/}, doi = {https://doi.org/10.5194/acp-2022-530} } |
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Liu, Y., Brito, J., Dorris, M.R., Rivera-Rios, J.C., Seco, R., Bate, K.H., Artaxo, P., Duvoisin Jr., S., Keutsch, F.N., Kim, S., Goldstein, A.H., Guenther, A.B., Manzi, A.O., Souza, R.A.F., Springston, S.R., Watson, T.B., McKinney, K.A. and Martin, S.T. | Isoprene photochemistry over the Amazon rainforest [BibTeX] |
2016 | Proceedings of the National Academy of Sciences of the United States of America | article | |
BibTeX:
@article{liu_isoprene_2016, author = {Liu, Yingjun and Brito, Joel and Dorris, Matthew R. and Rivera-Rios, Jean C. and Seco, Roger and Bate, Kelvin H. and Artaxo, Paulo and Duvoisin Jr., Sergio and Keutsch, Frank N. and Kim, Saewung and Goldstein, Allen H. and Guenther, Alex B. and Manzi, Antonio O. and Souza, Rodrigo A. F. and Springston, Stephen R. and Watson, Thomas B. and McKinney, Karen A. and Martin, Scot T.}, title = {Isoprene photochemistry over the Amazon rainforest}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2016} } |
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Liu, W.H., Bryant, D.M., Hutyra, L.R., Saleska, S.R., Hammond-Pyle, E., Curran, D. and Wofsy, S.C. | Woody debris contribution to the carbon budget of selectively logged and maturing mid-latitude forests | 2006 | Oecologia Vol. 148(1), pp. 108-117 |
article | DOI URL |
Abstract: Woody debris (WD) is an important component of forest C budgets, both as a C reservoir and source of CO2 to the atmosphere. We used an infrared gas analyzer and closed dynamic chamber to measure CO2 efflux from downed coarse WD (CWD; diameter textgreater= 7.5 cm) and fine WD (FWD; 7.5 cm textgreater diameter textgreater= 2 cm) to assess respiration in a selectively logged forest and a maturing forest (control site) in the northeastern USA. We developed two linear regression models to predict WD respiration: one based on WD temperature, moisture, and size (R-2=0.57), and the other on decay class and air temperature (R-2=0.32). WD respiration (0.28 +/- 0.09 Mg C ha(-1)year(-1)) contributed only approximate to 2% of total ecosystem respiration (12.3 +/- 0.7 Mg C ha(-1) year(-1), 1999-2003), but net C flux from CWD accounted for up to 30% of net ecosystem exchange in the maturing forest. C flux from CWD on the logged site increased modestly, from 0.61 +/- 0.29 Mg C ha(-1) year(-1) prior to logging to 0.77 +/- 0.23 Mg C ha(-1) year(-1) after logging, reflecting increased CWD stocks. FWD biomass and associated respiration flux were approximate to 7 times and approximate to 5 times greater, respectively, in the logged site than the control site. The net C flux associated with CWD, including inputs and respiratory outputs, was 0.35 +/- 0.19 Mg C ha(-1) year(-1)(net C sink) in the control site and -0.30 +/- 0.30 Mg C ha(-1)year(-1) (net C source) in the logged site. We infer that accumulation of WD may represent a small net C sink in maturing northern hardwood forests. Disturbance, such as selective logging, can enlarge the WD pool, increasing the net C flux from the WD pool to the atmosphere and potentially causing it to become a net C source. | |||||
BibTeX:
@article{liu_woody_2006, author = {Liu, W. H. and Bryant, D. M. and Hutyra, L. R. and Saleska, S. R. and Hammond-Pyle, E. and Curran, D. and Wofsy, S. C.}, title = {Woody debris contribution to the carbon budget of selectively logged and maturing mid-latitude forests}, journal = {Oecologia}, year = {2006}, volume = {148}, number = {1}, pages = {108--117}, note = {Edition: 2006/02/08}, url = {://WOS:000236968700012}, doi = {https://doi.org/10.1007/s00442-006-0356-9} } |
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Liu, L., Cheng, Y., Wang, S., Wei, C., Pöhlker, M.L., Pöhlker, C., Artaxo, P., Shrivastava, M., Andreae, M.O., Pöschl, U. and Su, H. | Impact of biomass burning aerosols on radiation, clouds, and precipitation over the Amazon: relative importance of aerosol–cloud and aerosol–radiation interactions [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(21), pp. 13283-13301 |
article | DOI URL |
BibTeX:
@article{liu_impact_2020, author = {Liu, L. and Cheng, Y. and Wang, S. and Wei, C. and Pöhlker, M. L. and Pöhlker, C. and Artaxo, P. and Shrivastava, M. and Andreae, M. O. and Pöschl, U. and Su, H.}, title = {Impact of biomass burning aerosols on radiation, clouds, and precipitation over the Amazon: relative importance of aerosol–cloud and aerosol–radiation interactions}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {21}, pages = {13283--13301}, url = {https://acp.copernicus.org/articles/20/13283/2020/}, doi = {https://doi.org/10.5194/acp-20-13283-2020} } |
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Liu, C.H. | A numerical investigation of a slow-moving convective line in a weakly sheared environment | 2005 | Advances in Atmospheric Sciences Vol. 22(5), pp. 625-639 |
article | DOI URL |
Abstract: A series of three-dimensional, cloud-resolving numerical simulations axe performed to examine a slow-propagating, quasi-two-dimensional convective system in a weakly sheared environment during the Tropical Rainfall Measuring Mission Large-Scale Biosphere-Atmosphere (TRMM-LBA) field campaign. The focus is on the kinematics and thermodynamics, organization mechanisms, and dynamical effects of low-level shear, ice microphysics and tropospheric humidity. The control simulation, which is initialized with the observed sounding and includes full microphysics, successfully replicates many observed features of the convective system, such as the linear structure, spatial orientation, life cycle, and sluggish translation. The system at the mature stage displays a line-normal structure similar to that associated with squall-type convective systems, but the corresponding mesoscale circulation and thermodynamic modification are much weaker. Ice-phase microphysical processes are not necessary to the formation of the convective system, but they play a non-trivial role in the late evolution stage. In contrast, the low-level shear, albeit shallow and weak, is critical to the realistic realization of the convective line. The tropospheric moisture above the planetary boundary layer has an important impact on the behavior of convective organization. In particular, a dry layer in the lower troposphere significantly suppresses convective development and inhibits the generation of organized convection even though the convective available potential energy is substantial. The free-atmosphere humidity has received little attention in previous studies of organized convection and warrants further investigation. | |||||
BibTeX:
@article{liu_numerical_2005, author = {Liu, C. H.}, title = {A numerical investigation of a slow-moving convective line in a weakly sheared environment}, journal = {Advances in Atmospheric Sciences}, year = {2005}, volume = {22}, number = {5}, pages = {625--639}, url = {://WOS:000232189200002}, doi = {https://doi.org/10.1007/bf02918706} } |
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Lin, J.C., Matsui, T., Pielke Sr., R.A. and Kummerow, C. | Effects of biomass-burning-derived aerosols on precipitation and clouds in the Amazon Basin: a satellite-based empirical study | 2006 | Journal of Geophysical Research-Atmospheres Vol. 111(D19) |
article | DOI URL |
Abstract: [ 1] Biomass burning in the Amazon provides strong input of aerosols into the atmosphere, with potential effects on precipitation, cloud properties, and radiative balance. However, few studies to date have systematically examined these effects at the scale of the Amazon Basin, over an entire burning season, using available data sets. We empirically study the relationships of aerosol optical depth (tau(a)) versus rainfall and cloud properties measured from satellites over the entire Brazilian Amazon during the dry, biomass burning seasons ( August - October) of 2000 and 2003. Elevated tau(a) was associated with increased rainfall in both 2000 and 2003. With enhanced tau(a), cloud cover increased significantly, and cloud top temperature/pressure decreased, suggesting higher cloud tops. The cloud droplet effective radius (R(e)) exhibited minimal growth with cloud height under background levels of tau(a), while distinct increases in R(e) at cloud top temperatures below - 10 degrees C, indicative of ice formation, were observed with aerosol loading. Although empirical correlations do not unequivocally establish the causal link from aerosols, these results are consistent with previous observational and modeling studies that pointed to dynamical effects from aerosols that invigorate convection, leading to higher clouds, enhanced cloud cover, and stronger rainfall. We speculate that changes in precipitation and cloud properties associated with aerosol loading observed in this study could have important radiative and hydrological effects on the Amazonian climate system. The accelerated forest burning for agricultural land clearing and the resulting enhancements in aerosols and rainfall may even partially account for the observed positive trend in Amazonian precipitation over the past several decades. | |||||
BibTeX:
@article{lin_effects_2006, author = {Lin, J. C. and Matsui, T. and Pielke, Sr., R. A. and Kummerow, C.}, title = {Effects of biomass-burning-derived aerosols on precipitation and clouds in the Amazon Basin: a satellite-based empirical study}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2006}, volume = {111}, number = {D19}, url = {://WOS:000241297000001}, doi = {https://doi.org/10.1029/2005jd006884} } |
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Lin, J.C., Gerbig, C., Wofsy, S.C., Daube, B.C., Matross, D.M., Chow, V.Y., Gottlieb, E., Andrews, A.E., Pathmathevan, M. and Munger, J.W. | What have we learned from intensive atmospheric sampling field programmes of CO(2)? | 2006 | Tellus Series B-Chemical and Physical Meteorology Vol. 58(5), pp. 331-343 |
article | DOI URL |
Abstract: The spatial and temporal gradients in atmospheric CO(2) contain signatures of carbon fluxes, and as part of inverse studies, these signatures have been combined with atmospheric models to infer carbon sources and sinks. However, such studies have yet to yield finer-scale, regional fluxes over the continent that can be linked to ecosystem processes and ground-based observations. The reasons for this gap are twofold: lack of atmospheric observations over the continent and model deficiencies in interpreting such observations. This paper describes a series of intensive atmospheric sampling field programmes designed as pilot experiments to bridge the observational gap over the continent and to help test and develop models to interpret these observations. We summarize recent results emerging from this work, outlining the role of the intensive atmospheric programmes in collecting CO(2) data in both the vertical and horizontal dimensions. These data: (1) quantitatively establish the spatial variability of CO(2) and the associated errors from neglecting this variability in models; (2) directly measure regional carbon fluxes from airmass-following experiments and (3) challenge models to reduce and account for uncertainties in atmospheric transport. We conclude with a look towards the future, outlining ways in which intensive atmospheric sampling can contribute towards advancing carbon science. | |||||
BibTeX:
@article{lin_what_2006, author = {Lin, J. C. and Gerbig, C. and Wofsy, S. C. and Daube, B. C. and Matross, D. M. and Chow, V. Y. and Gottlieb, E. and Andrews, A. E. and Pathmathevan, M. and Munger, J. W.}, title = {What have we learned from intensive atmospheric sampling field programmes of CO(2)?}, journal = {Tellus Series B-Chemical and Physical Meteorology}, year = {2006}, volume = {58}, number = {5}, pages = {331--343}, url = {://WOS:000241347500003}, doi = {https://doi.org/10.1111/j.1600-0889.2006.00202.x} } |
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Lin, J.C., Gerbig, C., Wofsy, S.C., Chow, V.Y., Gottlieb, E., Daube, B.C. and Matross, D.M. | Designing Lagrangian experiments to measure regional-scale trace gas fluxes | 2007 | Journal of Geophysical Research-Atmospheres Vol. 112(D13) |
article | DOI URL |
Abstract: Knowledge of trace gas fluxes at the land surface is essential for understanding the impact of human activities on the composition and radiative balance of the atmosphere. An ability to derive fluxes at the regional scale (on the order of 10(2)-10(4) km 2), at the scale of ecosystems and political borders, is crucial for policy and management responses. Lagrangian ("air mass-following") aircraft experiments have potential for providing direct estimates of regional-scale fluxes by measuring concentration changes in air parcels as they travel over the landscape. Successful Lagrangian experiments depend critically on forecasts of air parcel locations, rate of dispersion of air parcels, and proper assessment of forecast errors. We describe an operational tool to forecast air parcel locations and dispersion and to guide planning of flights for air mass-following experiments using aircraft. The tool consists of a particle dispersion model driven by mesoscale model forecasts from operational centers. The particle model simulates time-reversed motions of air parcels from specified locations, predicting the source regions which influence these locations. Forecast errors are incorporated into planning of Lagrangian experiments using statistics of wind errors derived by comparison with radiosonde data, as well as the model-to-model spread in forecast results. We illustrate the tool's application in a project designed to infer regional CO(2) fluxes-the CO(2) Budget and Rectification Airborne study, discuss errors in the forecasts, and outline future steps for further improvement of the tool. | |||||
BibTeX:
@article{lin_designing_2007, author = {Lin, J. C. and Gerbig, C. and Wofsy, S. C. and Chow, V. Y. and Gottlieb, E. and Daube, B. C. and Matross, D. M.}, title = {Designing Lagrangian experiments to measure regional-scale trace gas fluxes}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2007}, volume = {112}, number = {D13}, url = {://WOS:000248030200007}, doi = {https://doi.org/10.1029/2006jd008077} } |
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Lin, J.C., Gerbig, C., Wofsy, S.C., Andrews, A.E., Daube, B.C., Grainger, C.A., Stephens, B.B., Bakwin, P.S. and Hollinger, D.Y. | Measuring fluxes of trace gases at regional scales by Lagrangian observations: Application to the CO(2) Budget and Rectification Airborne (COBRA) study | 2004 | Journal of Geophysical Research-Atmospheres Vol. 109(D15) |
article | DOI URL |
Abstract: We present a general framework for designing and analyzing Lagrangian-type aircraft observations in order to measure surface fluxes of trace gases on regional scales. Lagrangian experiments minimize uncertainties due to advection by measuring tracer concentrations upstream and downstream of the study region, assuring that observed concentration changes represent fluxes within the region. The framework includes ( 1) a receptor-oriented model of atmospheric transport, including turbulent dispersion, ( 2) an upstream tracer boundary condition, ( 3) a surface flux model that predicts the distribution of tracer fluxes in time and space, and ( 4) a Bayesian inverse analysis that combines a priori information with observations to yield optimal estimates of tracer fluxes by the flux model. We use a receptor-oriented transport model, the Stochastic Time-Inverted Lagrangian Transport ( STILT) model, to simulate ensembles of particles representing air parcels transported backward in time from an observation point (receptor), linking receptor concentrations with upstream locations and surface inputs. STILT provides the capability to forecast flight tracks for Lagrangian experiments in the presence of atmospheric shear and dispersion. STILT may be used to forecast flight tracks that sample the upstream tracer boundary condition, or to analyze the data and provide optimized parameters in the surface flux model. We present a case study of regional scale surface CO(2) fluxes using data over the United States obtained in August 2000 in the CO(2) Budget and Rectification Airborne (COBRA-2000) study. STILT forecasts were obtained using the National Centers for Environmental Prediction Eta model to plan the flight tracks. Results from the Bayesian inversion showed large reductions in a priori errors for estimates of daytime ecosystem uptake of CO(2), but constraints on nighttime respiration fluxes were weaker, due to few observations of CO(2) in the nocturnal boundary layer. Derived CO(2) fluxes from the influence-following analysis differed notably from estimates using a conventional one-dimensional budget ("Boundary Layer Budget'') on a typical day, due to time-variable contributions from forests and croplands. A critical examination of uncertainties in the Lagrangian analyses revealed that the largest uncertainties were associated with errors in forecasting the upstream sampling locations and with aggregation of heterogeneous fluxes at the surface. Suggestions for improvements in future experiments are presented. | |||||
BibTeX:
@article{lin_measuring_2004, author = {Lin, J. C. and Gerbig, C. and Wofsy, S. C. and Andrews, A. E. and Daube, B. C. and Grainger, C. A. and Stephens, B. B. and Bakwin, P. S. and Hollinger, D. Y.}, title = {Measuring fluxes of trace gases at regional scales by Lagrangian observations: Application to the CO(2) Budget and Rectification Airborne (COBRA) study}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2004}, volume = {109}, number = {D15}, url = {://WOS:000223336200002}, doi = {https://doi.org/10.1029/2004jd004754} } |
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Lin, J.C., Gerbig, C., Wofsy, S.C., Andrews, A.E., Daube, B.C., Davis, K.J. and Grainger, C.A. | A near-field tool for simulating the upstream influence of atmospheric observations: The Stochastic Time-Inverted Lagrangian Transport (STILT) model | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D16) |
article | DOI URL |
Abstract: We introduce a tool to determine surface fluxes from atmospheric concentration data in the midst of distributed sources or sinks over land, the Stochastic Time-Inverted Lagrangian Transport (STILT) model, and illustrate the use of the tool with CO2 data over North America. Anthropogenic and biogenic emissions of trace gases at the surface cause large variations of atmospheric concentrations in the planetary boundary layer ( PBL) from the "near field," where upstream sources and sinks have strong influence on observations. Transport in the near field often takes place on scales not resolved by typical grid sizes in transport models. STILT provides the capability to represent near-field influences, transforming this noise to signal useful in diagnosing surface emissions. The model simulates transport by following the time evolution of a particle ensemble, interpolating meteorological fields to the subgrid scale location of each particle. Turbulent motions are represented by a Markov chain process. Significant computational savings are realized because the influence of upstream emissions at different times is modeled using a single particle simulation backward in time, starting at the receptor and sampling only the portion of the domain that influences the observations. We assess in detail the physical and numerical requirements of STILT and other particle models necessary to avoid inconsistencies and to preserve time symmetry (reversibility). We show that source regions derived from backward and forward time simulations in STILT are similar, and we show that deviations may be attributed to violation of mass conservation in currently available analyzed meterological fields. Using concepts from information theory, we show that the particle approach can provide significant gains in information compared to conventional gridcell models, principally during the first hours of transport backward in time, when PBL observations are strongly affected by surface sources and sinks. | |||||
BibTeX:
@article{lin_near-field_2003, author = {Lin, J. C. and Gerbig, C. and Wofsy, S. C. and Andrews, A. E. and Daube, B. C. and Davis, K. J. and Grainger, C. A.}, title = {A near-field tool for simulating the upstream influence of atmospheric observations: The Stochastic Time-Inverted Lagrangian Transport (STILT) model}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D16}, url = {://WOS:000184998800004}, doi = {https://doi.org/10.1029/2002jd003161} } |
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Lin, J.C., Gerbig, C., Daube, B.C., Wofsy, S.C., Andrews, A.E., Vay, S.A. and Anderson, B.E. | An empirical analysis of the spatial variability of atmospheric CO(2): Implications for inverse analyses and space-borne sensors | 2004 | Geophysical Research Letters Vol. 31(23) |
article | DOI URL |
Abstract: [ 1] We provide quantitative estimates for the spatial variability of CO(2), crucial for assessing representativeness of observations. Spatial variability determines the mismatch between point observations and spatial averages simulated by models or observed from space-borne sensors. Such "representation errors'' must be properly specified in determining the leverage of observations to retrieve surface fluxes or to validate space-borne sensors. We empirically derive the spatial variability and representation errors for tropospheric CO2 over the North American continent and the Pacific Ocean, using in-situ observations from extensive aircraft missions. The spatial variability and representation error of CO2 is smaller over the Pacific than the continent, particularly in the lowest altitudes, and decreases with altitude. Representation errors resulting from spatial variability in the summer continental PBL are as large as 1-2 ppmv for typical grid resolutions used in current models for inverse analyses. | |||||
BibTeX:
@article{lin_empirical_2004, author = {Lin, J. C. and Gerbig, C. and Daube, B. C. and Wofsy, S. C. and Andrews, A. E. and Vay, S. A. and Anderson, B. E.}, title = {An empirical analysis of the spatial variability of atmospheric CO(2): Implications for inverse analyses and space-borne sensors}, journal = {Geophysical Research Letters}, year = {2004}, volume = {31}, number = {23}, url = {://WOS:000225583300001}, doi = {https://doi.org/10.1029/2004gl020957} } |
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Lima, W.F.A., Machado, L.A.T., Morales, C.A. and Viltard, N. | Rainfall sensitivity analyses for the HSB sounder: an Amazon case study | 2007 | International Journal of Remote Sensing Vol. 28(16), pp. 3529-3545 |
article | URL |
Abstract: This work examines the sensitivity of the different channels of the HSB (Humidity Sensor for Brazil), on board the AQUA satellite, for the purpose of retrieving surface rainfall over land. The analysis is carried out in two steps: (a) a theoretical study performed using two radiative transfer models, RTTOV and the so-called Eddington method; and (b) the determination of the correlation between coincident measurements of HSB brightness temperatures and radar rainfall estimates during the DRY-TO-WET/AMC/LBA field campaign held in the Amazon region during September and October 2002. Theoretical results indicate the sensitivity of the HSB to water vapour content and cloud liquid water in the precipitation estimation. Theoretical and experimental analyses show that the channels 150 and 183 +/- 7 GHz are more adapted to estimate precipitation than the 183 +/- 1 and 183 +/- 3 GHz channels. The simulation analyses clearly show a hierarchy in physical effects that determine the brightness temperature of these channels. The rain and ice scattering dominate over the absorption of liquid water, and the liquid water absorption effect dominates over the absorption of water vapour. The results show that the 150 and 183 +/- 7 channels are more sensitive to the variation of liquid water and ice than the 183 +/- 1 and 183 +/- 3 channels. For the precipitation estimation using these channels, it was found that it is best adapted to the low precipitation rate situations, since the brightness temperature is rapidly saturated in the presence of high intense precipitation. A case study to estimate precipitation using the radar data has shown that it is possible to adjust a curve that relates the precipitation rate to the brightness temperature of the 150 GHz channel with a good level of accuracy for low precipitation rates. | |||||
BibTeX:
@article{lima_rainfall_2007, author = {Lima, W. F. A. and Machado, L. A. T. and Morales, C. A. and Viltard, N.}, title = {Rainfall sensitivity analyses for the HSB sounder: an Amazon case study}, journal = {International Journal of Remote Sensing}, year = {2007}, volume = {28}, number = {16}, pages = {3529--3545}, url = {://WOS:000248731200007} } |
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Lima, W. and Machado, L. | O uso do sensor HSB na estimativa do conteúdo integrado de vapor d’água: um exemplo usando os dados do experimento RACCI/LBA [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(2), pp. 211-219 |
article | |
BibTeX:
@article{lima_o_2006, author = {Lima, W.F.A. and Machado, L.A.T.}, title = {O uso do sensor HSB na estimativa do conteúdo integrado de vapor d’água: um exemplo usando os dados do experimento RACCI/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {2}, pages = {211--219} } |
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Lima, W. and Machado, L. | Analise do sensor HSB na estimativa do conteúdo integrado de vapor d’água durante o experimento RACCI/LBA [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(2), pp. 01-08 |
article | |
BibTeX:
@article{lima_analise_2006, author = {Lima, W.F.A. and Machado, L.A.T.}, title = {Analise do sensor HSB na estimativa do conteúdo integrado de vapor d’água durante o experimento RACCI/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {2}, pages = {01--08} } |
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Lima, N.S.d., Tóta, J., Bolzan, M.J.A., Vale, R.d. and Santana, R. | Característica aerodinâmica da turbulência sobre e dentro do dossel de uma floresta de terra firme na amazônia central [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 375 - 379 |
article | |
BibTeX:
@article{lima_caracteristica_2013, author = {Lima, Newton Silva de and Tóta, Julio and Bolzan, Maurício José Alves and Vale, Roseilson do and Santana, Raoni}, title = {Característica aerodinâmica da turbulência sobre e dentro do dossel de uma floresta de terra firme na amazônia central}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {375 -- 379} } |
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Lima, M.A. and Wilson, J.W. | Convective storm initiation in a moist tropical environment | 2008 | Monthly Weather Review Vol. 136(6), pp. 1847-1864 |
article | DOI URL |
Abstract: Radar and satellite data from the Tropical Rainfall Measuring Mission-Large-Scale Biosphere-Atmosphere (TRMM-LBA) project have been examined to determine causes for convective storm initiation in the southwest Amazon region. The locations and times of storm initiation were based on the National Center for Atmospheric Research (NCAR) S-band dual-polarization Doppler radar (S-Pol). Both the radar and the Geostationary Operational Environmental Satellite-8 (GOES-8) visible data were used to identify cold pools produced by convective precipitation. These data along with high-resolution topographic data were used to determine possible convective storm triggering mechanisms. The terrain elevation varied from 100 to 600 m. Tropical forests cover the area with numerous clear-cut areas used for cattle grazing and farming. This paper presents the results from 5 February 1999. A total of 315 storms were initiated within 130 km of the S-Pol radar. This day was classified as a weak monsoon regime where convection developed in response to the diurnal cycle of solar heating. Scattered shallow cumulus during the morning developed into deep convection by early afternoon. Storm initiation began about 1100 LST and peaked around 1500-1600 LST. The causes of storm initiation were classified into four categories. The most common initiation mechanism was caused by forced lifting by a gust front (GF; 36%). Forcing by terrain (textgreater300 m) without any other triggering mechanism accounted for 21% of the initiations and colliding GFs accounted for 16%. For the remaining 27% a triggering mechanism was not identified. Examination of all days during TRMM-LBA showed that this one detailed study day was representative of many days. A conceptual model of storm initiation and evolution is presented. The results of this study should have implications for other locations when synoptic-scale forcing mechanisms are at a minimum. These results should also have implications for very short-period forecasting techniques in any location where terrain, GFs, and colliding boundaries influence storm evolution. | |||||
BibTeX:
@article{lima_convective_2008, author = {Lima, Maria Andrea and Wilson, James W.}, title = {Convective storm initiation in a moist tropical environment}, journal = {Monthly Weather Review}, year = {2008}, volume = {136}, number = {6}, pages = {1847--1864}, url = {://WOS:000257239300002}, doi = {https://doi.org/10.1175/2007mwr2279.1} } |
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Lima, I.B.T., Rosa, R.R., Ramos, F.M. and Novo, E. | Water level dynamics in the Amazon floodplain | 2003 | Advances in Water Resources Vol. 26(7), pp. 725-732 |
article | DOI URL |
Abstract: Nonlinear analysis of Amazonian River systems suggests that water level variability is due to Brownian-like motions B-H. Dynamical properties of the water level is probably a response of rainfall and runoff smoothing by the stored water in the floodplain; additional inputs of water results in attenuated perturbations of the water level. This implies that noise is a self-affine fractal with scale invariance, and in accordance with surrogate and correlation dimension analysis, which refused the hypothesis of low dimensional chaos for water level dynamics. Opposing to the chaotic approach, we present a fractal model formed by a periodic signal and a BH process that mimics original water level variability. Dynamical exponents are remarkably similar between real and modeled data when BH influence is about 1% the amplitude of the periodic signal. In comparison to natural systems, a hydroelectric reservoir produces different exponents, due to the control of the water level, as demonstrated for the Tucurui dam in the Tocantins River. The Amazon floodplain at Obidos and Curuai exhibits a fortnight cycle most probably due to bore tide influence in the river mouth. (C) 2003 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{lima_water_2003, author = {Lima, I. B. T. and Rosa, R. R. and Ramos, F. M. and Novo, Emlm}, title = {Water level dynamics in the Amazon floodplain}, journal = {Advances in Water Resources}, year = {2003}, volume = {26}, number = {7}, pages = {725--732}, url = {://WOS:000183758100003}, doi = {https://doi.org/10.1016/s0309-1708(03)00052-6} } |
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Lima Barbosa, C.N.E.C.J.S.J.I. | Localização de áreas de monitoramento telemétrico em ambientes aquáticos da Amazônia [BibTeX] |
2006 | Acta Amazonica Vol. 36(3), pp. 331 - 334 |
article | |
BibTeX:
@article{lima_localizacao_2006, author = {Lima, Barbosa, C.C., Novo, E.M.L.M., Carvalho J.C., Stech, J.L., I.B.T.}, title = {Localização de áreas de monitoramento telemétrico em ambientes aquáticos da Amazônia}, journal = {Acta Amazonica}, year = {2006}, volume = {36}, number = {3}, pages = {331 -- 334} } |
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Lima, I.B.T. | Blogeochemical distinction of methane releases from two Amazon hydroreservoirs | 2005 | Chemosphere Vol. 59(11), pp. 1697-1702 |
article | DOI URL |
Abstract: Biogeochemical distinction of methane emissions to the atmosphere may essentially rely on the surface area and morphometry of Amazon hydroreservoirs. Tucurui (deep) and Samuel (shallow) reservoirs released in average 13.82 +/- 22.94 and 71.19 +/- 107.4 mg CH4 m(-2) d(-1), respectively. delta(13)C-CH4 values from the sediments to the atmosphere indicate that the deep reservoir has extended methanotrophic layer, oxidizing large quantities of light isotope methane coming from the sediments, while sediment-generated methane can easily evade the shallow reservoir. (c) 2005 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{lima_blogeochemical_2005, author = {Lima, I. B. T.}, title = {Blogeochemical distinction of methane releases from two Amazon hydroreservoirs}, journal = {Chemosphere}, year = {2005}, volume = {59}, number = {11}, pages = {1697--1702}, note = {Edition: 2005/05/17}, url = {://WOS:000230321500017}, doi = {https://doi.org/10.1016/j.chemosphere.2004.12.011} } |
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Lima, A.P., Cordeiro-Duarte, A.C., Luizao, F.J. and Higuchi, N. | Effect of selective logging intensity on two termite species of the genus Syntermes in Central Amazonia | 2000 | Forest Ecology and Management Vol. 137(1-3), pp. 151-154 |
article | DOI URL |
Abstract: We studied the effect of experimental logging on two species of termites of the genus Syntermes in 11 plots of 4 ha in a forest 90 km north of Manaus, Amazonas, Brazil. The density of S. chaquimayensis decreased with increase in logging damage suffered 9-10 years before: the study, whereas S. molestus was not significantly affected. S. chaquimayensis is the most abundant species of termite on plateauxs in undisturbed forest on heavy clay latosolos in Amazonia. That species removes leaf disks almost twice the size of other species of Syntermes. Therefore, disturbances such as logging, which reduces the abundance of this species could reduce the rate of litter breakdown in the forest. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{lima_effect_2000, author = {Lima, A. P. and Cordeiro-Duarte, A. C. and Luizao, F. J. and Higuchi, N.}, title = {Effect of selective logging intensity on two termite species of the genus Syntermes in Central Amazonia}, journal = {Forest Ecology and Management}, year = {2000}, volume = {137}, number = {1-3}, pages = {151--154}, url = {://WOS:000089269400014}, doi = {https://doi.org/10.1016/s0378-1127(99)00323-0} } |
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Lima Machado, L.&.L.H.A. | A divergência do vento em altos níveis e sua relação com a cobertura de nuvens e a precipitação, durante o WETAMC/LBA [BibTeX] |
2003 | Revista Brasileira de Meteorologia Vol. 18, pp. 105-117 |
article | |
BibTeX:
@article{lima_divergencia_2003, author = {Lima, Machado, L.A.T. & Laurent, H., A.A.}, title = {A divergência do vento em altos níveis e sua relação com a cobertura de nuvens e a precipitação, durante o WETAMC/LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2003}, volume = {18}, pages = {105--117} } |
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Liebmann, B., Marengo, J.A., Glick, J.D., Kousky, V.E., Wainer, I.C. and Massambani, O. | A comparison of rainfall, outgoing longwave radiation, and divergence over the Amazon Basin | 1998 | Journal of Climate Vol. 11(11), pp. 2898-2909 |
article | DOI URL |
Abstract: Observed rainfall. outgoing longwave radiation (OLR), divergence, and precipitation from the reanalysis project of the National Centers for Environmental Prediction and die National Center for Atmospheric Research art: compared over the Amazon Basin. The spatial pattern of the mean and the phase of the annual cycle generally compare well. except that the amplitude of the annual cycle of model precipitation is much smaller than observed. On 10-30-day timescales. it is shown that averaging stations within a 5 degrees radius is approximately equivalent to total wavenumber 20 (T20) spatial scale. although it is more important to have a high density of stations than an exact match of spatial scales. Ideally, there should be one station per 20 000 km(2). On 10-30-day scales, observed rainfall is best correlated with OLR. Correlations between OLR and 150-mb divergence are larger than between observed rainfall and divergence or between rainfall and model precipitation. For example, if 10-30-day filtered OLR and divergence are truncated at T20 and rainfall is averaged to include stations within a 5 degrees radius. OLR is correlated with rainfall at about -0.6, OLR is correlated with divergence at about -0.35, and rainfall is correlated with divergence at about 0.2. At least part of the lack of correlation is due to inadequate spatial sampling of rainfall. Correlations improve with larger spatial scale. The major seasonal transitions from dry to rainy regimes are captured well by OLR but not by the model quantities. The mean diurnal cycle is represented reasonably by 150-mb divergence. | |||||
BibTeX:
@article{liebmann_comparison_1998, author = {Liebmann, B. and Marengo, J. A. and Glick, J. D. and Kousky, V. E. and Wainer, I. C. and Massambani, O.}, title = {A comparison of rainfall, outgoing longwave radiation, and divergence over the Amazon Basin}, journal = {Journal of Climate}, year = {1998}, volume = {11}, number = {11}, pages = {2898--2909}, url = {://WOS:000077171400012}, doi = {https://doi.org/10.1175/1520-0442(1998)011%3C2898:acorol%3E2.0.co;2} } |
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Liebmann, B. and Marengo, J.A. | Interannual variability of the rainy season and rainfall in the Brazilian Amazon basin | 2001 | Journal of Climate Vol. 14(22), pp. 4308-4318 |
article | DOI URL |
Abstract: Interannual variability of seasonal rainfall in the Brazilian Amazon basin is examined in context of its relationship to sea surface temperatures in the tropical Pacific and Atlantic Oceans. Linear correlations reveal strong relationships, but rainfall patterns are of regional scale. Areas of rainfall exhibiting strong relationships with SST are confined to the equatorial region of the Brazilian Amazon. The best relationships are found either during the season of transition between wet and dry regimes, or entirely within the dry season. It is hypothesized, and results are shown in support, that during the transition seasons, an important contributor to the SST control on seasonal totals is its influence on the timing on the rainy season onset or end. That influence appears to be stronger than the SST influence on the rainy season rain rate. | |||||
BibTeX:
@article{liebmann_interannual_2001, author = {Liebmann, B. and Marengo, J. A.}, title = {Interannual variability of the rainy season and rainfall in the Brazilian Amazon basin}, journal = {Journal of Climate}, year = {2001}, volume = {14}, number = {22}, pages = {4308--4318}, url = {://WOS:000171924600005}, doi = {https://doi.org/10.1175/1520-0442(2001)014%3C4308:ivotrs%3E2.0.co;2} } |
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Liang, B., Lehmann, J., Solomon, D., Sohi, S., Thies, J.E., Skjemstad, J.O., Luizao, F.J., Engelhard, M.H., Neves, E.G. and Wirick, S. | Stability of biomass-derived black carbon in soils | 2008 | Geochimica Et Cosmochimica Acta Vol. 72(24), pp. 6069-6078 |
article | DOI URL |
Abstract: Black carbon (BC) may play ail important role in the global C budget, due to its potential to act as a significant sink of atmospheric CO(2). In order to fully evaluate the influence of BC oil the global C cycle, in understanding of the stability of BC is required. The biochemical stability of BC was assessed in a chronosequence of high-BC-containing Anthrosols from the central Amazon, Brazil, using a range of spectroscopic and biological methods. Results revealed that the Anthrosols had 61-80% lower (P textless 0.05) CO(2) evolution per unit C over 532 days compared to their respective adjacent soils with low BC contents. No significant (P textgreater 0.05) difference in CO(2) respiration per unit C was observed between Anthrosols with contrasting ages of BC (600-8700 years BP) Lind soil textures (0.3-36% clay). Similarly, the molecular composition of the core regions of micrometer-sized BC particles quantified by synchrotron-based Near-Edge X-ray Fine Structure (NEXAFS) spectroscopy coupled to Scanning Transmission X-ray Microscopy (STXM) remained similar regardless of their ages and closely resembled the spectral characteristics or fresh BC. BC decomposed extremely slowly to ail extent that it was not possible to detect chemical changes between Youngest and oldest samples, as also confirmed by X-ray Photoelectron Spectroscopy (XPS). Deconvolution of NEXAFS spectra revealed greater oxidation oil the surfaces of BC particles with little penetration into the core of the particles. The similar C mineralization between different BC-rich soils regardless of soil texture underpins the importance of chemical recalcitrance for the stability of BC, in contrast to adjacent soils which showed the highest mineralization in the sandiest soil. However, the BC-rich Anthrosols had higher proportions (72-90%) of C in the more stable organo-mineral fraction than BC-poor adjacent soils (2-70%), Suggesting some degree of physical stabilization. (c) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{liang_stability_2008, author = {Liang, Biqing and Lehmann, Johannes and Solomon, Dawit and Sohi, Saran and Thies, Janice E. and Skjemstad, Jan O. and Luizao, Flavio J. and Engelhard, Mark H. and Neves, Eduardo G. and Wirick, Sue}, title = {Stability of biomass-derived black carbon in soils}, journal = {Geochimica Et Cosmochimica Acta}, year = {2008}, volume = {72}, number = {24}, pages = {6069--6078}, url = {://WOS:000261914200017}, doi = {https://doi.org/10.1016/j.gca.2008.09.028} } |
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Liang, B., Lehmann, J., Solomon, D., Kinyangi, J., Grossman, J., O'Neill, B., Skjemstad, J.O., Thies, J., Luizao, F.J., Petersen, J. and Neves, E.G. | Black Carbon increases cation exchange capacity in soils | 2006 | Soil Science Society of America Journal Vol. 70(5), pp. 1719-1730 |
article | DOI URL |
Abstract: Black Carbon (BC) may significantly affect nutrient retention and play a key role in a wide range of biogeochemical processes in soils, especially for nutrient cycling. Anthrosols from the Brazilian Amazon (ages between 600 and 8700 yr BP) with high contents of biomass-derived BC had greater potential cation exchange capacity (CEC measured at pH 7) per unit organic C than adjacent soils with low BC contents. Synchrotron-based near edge X-ray absorption fine structure (NEXAFS) spectroscopy coupled with scanning transmission X-ray microscopy (STXM) techniques explained the source of the higher surface charge of BC compared with non-BC by mapping cross-sectional areas of BC particles with diameters of 10 to 50 mu m for C forms. The largest cross-sectional areas consisted of highly aromatic or only slightly oxidized organic C most likely originating from the BC itself with a characteristic peak at 286.1 eV, which could not be found in humic substance extracts, bacteria or fungi. Oxidation significantly increased from the core of BC particles to their surfaces as shown by the ratio of carboxyl-C/aromatic-C. Spotted and non-continuous distribution patterns of highly oxidized C functional groups with distinctly different chemical signatures on BC particle surfaces (peak shift at 286.1 eV to a higher energy of 286.7 eV) indicated that non-BC may be adsorbed on the surfaces of BC particles creating highly oxidized surface. As a consequence of both oxidation of the BC particles themselves and adsorption of organic matter to BC surfaces, the charge density (potential CEC per unit surface area) was greater in BC-rich Anthrosols than adjacent soils. Additionally, a high specific surface area was attributable to the presence of BC, which may contribute to the high CEC found in soils that are rich in BC. | |||||
BibTeX:
@article{liang_black_2006, author = {Liang, B. and Lehmann, J. and Solomon, D. and Kinyangi, J. and Grossman, J. and O'Neill, B. and Skjemstad, J. O. and Thies, J. and Luizao, F. J. and Petersen, J. and Neves, E. G.}, title = {Black Carbon increases cation exchange capacity in soils}, journal = {Soil Science Society of America Journal}, year = {2006}, volume = {70}, number = {5}, pages = {1719--1730}, url = {://WOS:000240666800030}, doi = {https://doi.org/10.2136/sssaj2005.0383} } |
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Liang, B., Lehmann, J., Sohi, S.P., Thies, J.E., O'Neill, B., Trujillo, L., Gaunt, J., Solomon, D., Grossman, J., Neves, E.G. and Luizao, F.J. | Black carbon affects the cycling of non-black carbon in soil | 2010 | Organic Geochemistry Vol. 41(2), pp. 206-213 |
article | DOI URL |
Abstract: Black carbon (BC) is an important fraction of many soils worldwide and plays an important role in global C biogeochemistry. However, few studies have examined how it influences the mineralization of added organic matter (AOM) and its incorporation into soil physical fractions and whether BC decomposition is increased by AOM. BC-rich Anthrosols and BC-poor adjacent soils from the Central Amazon (Brazil) were incubated for 532 days either with or without addition of (13)C-isotopically different plant residue. Total C mineralization from the BC-rich Anthrosols with AOM was 25.5% (P textless 0.05) lower than with mineralization from the BC-poor adjacent soils. The AOM contributed to a significantly (P textless 0.05) higher proportion to the total C mineralized in the BC-rich Anthrosols (91-92%) than the BC-poor adjacent soils (69-80%). The AOM was incorporated more rapidly in BC-rich than BC-poor soils from the separated free light fraction through the intra-aggregate light fraction into the stable organo-mineral fraction and up to 340% more AOM was found in the organo-mineral fraction. This more rapid stabilization was observed despite a significantly (P textless 0.05) lower metabolic quotient for BC-rich Anthrosols. The microbial biomass (MB) was up to 125% greater (P textless 0.05) in BC-rich Anthrosols than BC-poor adjacent soils. To account for increased MB adsorption onto BC during fumigation extraction, a correction factor was developed via addition of a (13)C-enriched microbial culture. The recovery was found to be 21-41 % lower (P textless 0.05) for BC-rich than BC-poor soils due to re-adsorption of MB onto BC. Mineralization of native soil C was enhanced to a significantly greater degree in BC-poor adjacent soils compared to BC-rich Anthrosols as a result of AOM. No positive priming by way of cometabolism due to AOM could be found for aged BC in the soils. (C) 2009 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{liang_black_2010, author = {Liang, Biqing and Lehmann, Johannes and Sohi, Saran P. and Thies, Janice E. and O'Neill, Brendan and Trujillo, Lucerina and Gaunt, John and Solomon, Dawit and Grossman, Julie and Neves, Eduardo G. and Luizao, Flavio J.}, title = {Black carbon affects the cycling of non-black carbon in soil}, journal = {Organic Geochemistry}, year = {2010}, volume = {41}, number = {2}, pages = {206--213}, url = {://WOS:000274770000018}, doi = {https://doi.org/10.1016/j.orggeochem.2009.09.007} } |
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Li, W., Fu, R., Juarez, R.I.N. and Fernandes, K. | Observed change of the standardized precipitation index, its potential cause and implications to future climate change in the Amazon region | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1767-1772 |
article | DOI URL |
Abstract: Observations show that the standard precipitation index (SPI) over the southern Amazon region decreased in the period of 1970-1999 by 0.32 per decade, indicating an increase in dry conditions. Simulations of constant pre-industrial climate with recent climate models indicate a low probability (p=0%) that the trends are due to internal climate variability. When the 23 models are forced with either anthropogenic factors or both anthropogenic and external natural factors, approximately 13% of sampled 30-year SPI trends from the models are found to be within the range of the observed SPI trend at 95% confidence level. This suggests a possibility of anthropogenic and external forcing of climate change in the southern Amazon. On average, the models project no changes in the frequency of occurrence of low SPI values in the future; however, those models which produce more realistic SPI climatology, variability and trend over the period 1970-1999 show more of a tendency towards more negative values of SPI in the future. The analysis presented here suggests a potential anthropogenic influence on Amazon drying, which warrants future, more in-depth, study. | |||||
BibTeX:
@article{li_observed_2008, author = {Li, W. and Fu, R. and Juarez, Robinson I. Negron and Fernandes, Katia}, title = {Observed change of the standardized precipitation index, its potential cause and implications to future climate change in the Amazon region}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1767--1772}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500007}, doi = {https://doi.org/10.1098/rstb.2007.0022} } |
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Li, R. and Min, Q. | Dynamic response of microwave land surface properties to precipitation in Amazon rainforest [BibTeX] |
2013 | Remote Sensing of Environment Vol. 133, pp. 183-192 |
article | |
BibTeX:
@article{li_dynamic_2013, author = {Li, Rui and Min, Qilong}, title = {Dynamic response of microwave land surface properties to precipitation in Amazon rainforest}, journal = {Remote Sensing of Environment}, year = {2013}, volume = {133}, pages = {183--192} } |
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Lewis, S.L., Phillips, O.L., Sheil, D., Vinceti, B., Baker, T.R., Brown, S., Graham, A.W., Higuchi, N., Hilbert, D.W., Laurance, W.F., Lejoly, J., Malhi, Y., Monteagudo, A., Vargas, P.N., Sonke, B., Supardi, N., Terborgh, J.W. and Martinez, R.V. | Tropical forest tree mortality, recruitment and turnover rates: calculation, interpretation and comparison when census intervals vary | 2004 | Journal of Ecology Vol. 92(6), pp. 929-944 |
article | DOI URL |
Abstract: 1. Mathematical proofs show that rate estimates, for example of mortality and recruitment, will decrease with increasing census interval when obtained from censuses of non-homogeneous populations. This census interval effect could be confounding or perhaps even driving conclusions from comparative studies involving such rate estimates. 2. We quantify this artefact for tropical forest trees, develop correction methods and re-assess some previously published conclusions about forest dynamics. 3. Mortality rates of textgreater 50 species at each of seven sites in Africa, Latin America, Asia and Australia were used as subpopulations to simulate stand-level mortality rates in a heterogeneous population when census intervals varied: all sites showed decreasing stand mortality rates with increasing census interval length. 4. Stand-level mortality rates from 14 multicensus long-term forest plots from Africa, Latin America, Asia and Australia also showed that, on average, mortality rates decreased with increasing census interval length. 5. Mortality, recruitment or turnover rates with differing census interval lengths can be compared using the mean rate of decline from the 14 long-term plots to standardize estimates to a common census length using lambda(corr) = lambda x t(0.08), where lambda is the rate and t is time between censuses in years. This simple general correction should reduce the bias associated with census interval variation, where it is unavoidable. 6. Re-analysis of published results shows that the pan-tropical increase in stem turnover rates over the late 20th century cannot be attributed to combining data with differing census intervals. In addition, after correction, Old World tropical forests do not have significantly lower turnover rates than New World sites, as previously reported. Our pan-tropical best estimate adjusted stem turnover rate is 1.81 +/- 0.16% a(-1) (mean +/- 95% CI, n = 65). 7. As differing census intervals affect comparisons of mortality, recruitment and turnover rates, and can lead to erroneous conclusions, standardized field methods, the calculation of local correction factors at sites where adequate data are available, or the use of our general standardizing formula to take account of sample intervals, are to be recommended. | |||||
BibTeX:
@article{lewis_tropical_2004, author = {Lewis, S. L. and Phillips, O. L. and Sheil, D. and Vinceti, B. and Baker, T. R. and Brown, S. and Graham, A. W. and Higuchi, N. and Hilbert, D. W. and Laurance, W. F. and Lejoly, J. and Malhi, Y. and Monteagudo, A. and Vargas, P. N. and Sonke, B. and Supardi, N. and Terborgh, J. W. and Martinez, R. V.}, title = {Tropical forest tree mortality, recruitment and turnover rates: calculation, interpretation and comparison when census intervals vary}, journal = {Journal of Ecology}, year = {2004}, volume = {92}, number = {6}, pages = {929--944}, url = {://WOS:000225631400001}, doi = {https://doi.org/10.1111/j.0022-0477.2004.00923.x} } |
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Lewis, S.L., Phillips, O.L., Baker, T.R., Lloyd, J., Malhi, Y., Almeida, S., Higuchi, N., Laurance, W.F., Neill, D.A., Silva, J.N.M., Terborgh, J., Lezama, A.T., Martinez, R.V., Brown, S., Chave, J., Kuebler, C., Vargas, P.N. and Vinceti, B. | Concerted changes in tropical forest structure and dynamics: evidence from 50 South American long-term plots | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 421-436 |
article | DOI URL |
Abstract: Several widespread changes in the ecology of old-growth tropical forests have recently been documented for the late twentieth century, in particular an increase in stem turnover (pan-tropical), and an increase in above-ground biomass (neotropical). Whether these changes are synchronous and whether changes in growth are also occurring is not known. We analysed stand-level changes within 50 long-term. monitoring plots from across South America spanning 1971-2002. We show that: (i) basal area (BA: sum of the cross-sectional areas of all trees in a plot) increased significantly over time (by 0.10 +/- 0.04 m(2) ha(-1) yr(-1), mean +/- 95% CI); as did both (ii) stand-level BA growth rates (sum of the increments of BA of surviving trees and BA of new trees that recruited into a plot); and (iii) stand-level BA mortality rates (sum of the cross-sectional areas of all trees that died in a plot). Similar patterns were observed on a per-stem basis: (i) stem density (number of stems per hectare; 1 hectare is 10(4) m(2)) increased significantly over time (0.94 +/- 0.63 stems ha(-1) yr(-1)); as did both (ii) stem recruitment rates; and (iii) stem mortality rates. In relative terms, the pools of BA and stem density increased by 0.38 +/- 0.15% and 0.18 +/- 0.12% yr(-1), respectively. The fluxes into and out of these pools-stand-level BA growth, stand-level BA mortality, stem recruitment and stem mortality rates-increased, in relative terms, by an order of magnitude more. The gain terms (BA growth, stem recruitment) consistently exceeded the loss terms (BA loss, stem mortality) throughout the period, suggesting that whatever process is driving these changes was already acting before the plot network was established. Large long-term increases in stand-level BA growth and simultaneous increases in stand BA and stem density imply a continent-wide increase in resource availability which is increasing net primary productivity and altering forest dynamics. Continent-wide changes in incoming solar radiation, and increases in atmospheric concentrations of CO2 and air temperatures may have increased resource supply over recent decades, thus causing accelerated growth and increased dynamism across the world's largest tract of tropical forest. | |||||
BibTeX:
@article{lewis_concerted_2004, author = {Lewis, S. L. and Phillips, O. L. and Baker, T. R. and Lloyd, J. and Malhi, Y. and Almeida, S. and Higuchi, N. and Laurance, W. F. and Neill, D. A. and Silva, J. N. M. and Terborgh, J. and Lezama, A. T. and Martinez, R. V. and Brown, S. and Chave, J. and Kuebler, C. and Vargas, P. N. and Vinceti, B.}, title = {Concerted changes in tropical forest structure and dynamics: evidence from 50 South American long-term plots}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {421--436}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100009}, doi = {https://doi.org/10.1098/rstb.2003.1431} } |
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Lewis, S.L., Phillips, O.L. and Baker, T.R. | Impacts of global atmospheric change on tropical forests [BibTeX] |
2006 | Trends in Ecology & Evolution Vol. 21(4), pp. 173-174 |
article | DOI URL |
BibTeX:
@article{lewis_impacts_2006, author = {Lewis, S. L. and Phillips, O. L. and Baker, T. R.}, title = {Impacts of global atmospheric change on tropical forests}, journal = {Trends in Ecology & Evolution}, year = {2006}, volume = {21}, number = {4}, pages = {173--174}, note = {Edition: 2006/05/17}, url = {://WOS:000237144500003}, doi = {https://doi.org/10.1016/j.tree.2006.02.001} } |
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Lewis, S.L., Malhi, Y. and Phillips, O.L. | Fingerprinting the impacts of global change on tropical forests | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 437-462 |
article | DOI URL |
Abstract: Recent observations of widespread changes in mature tropical forests such as increasing tree growth, recruitment and mortality rates and increasing above-ground biomass suggest that 'global change' agents may be causing predictable changes in tropical forests. However, consensus over both the robustness of these changes and the environmental drivers that may be causing them is yet to emerge. This paper focuses on the second part of this debate. We review (i) the evidence that the physical, chemical and biological environment that tropical trees grow in has been altered over recent decades across large areas of the tropics, and (ii) the theoretical, experimental and observational evidence regarding the most likely effects of each of these changes on tropical forests. Ten potential widespread drivers of environmental change were identified: temperature, precipitation, solar radiation, climatic extremes (including El Nino-Southern Oscillation events), atmospheric CO2 concentrations, nutrient deposition, O-3/acid depositions, hunting, land-use change and increasing liana numbers. We note that each of these environmental changes is expected to leave a unique 'fingerprint' in tropical forests, as drivers directly force different processes, have different distributions in space and time and may affect some forests more than others (e.g. depending on soil fertility). Thus, in the third part of the paper we present testable a priori predictions of forest responses to assist ecologists in attributing particular changes in forests to particular causes across multiple datasets. Finally, we discuss how these drivers may change in the future and the possible consequences for tropical forests. | |||||
BibTeX:
@article{lewis_fingerprinting_2004, author = {Lewis, S. L. and Malhi, Y. and Phillips, O. L.}, title = {Fingerprinting the impacts of global change on tropical forests}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {437--462}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100010}, doi = {https://doi.org/10.1098/rstb.2003.1432} } |
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Lewis, S.L., Lloyd, J., Sitch, S., Mitchard, E.T.A. and Laurance, W.F. | Changing Ecology of Tropical Forests: Evidence and Drivers | 2009 | Vol. 40Annual Review of Ecology Evolution and Systematics, pp. 529-549 |
incollection | DOI URL |
Abstract: Global environmental changes may be altering the ecology of tropical forests. Long-term monitoring plots have provided much of the evidence for large-scale, directional changes in tropical forests, but the results have been controversial. Here we review evidence from six complementary approaches to understanding possible changes: plant physiology experiments, long-term monitoring plots, ecosystem flux techniques, atmospheric measurements, Earth observations, and global-scale vegetation models. Evidence from four of these approaches suggests that large-scale, directional changes are occurring in the ecology of tropical forests, with the other two approaches providing inconclusive results. Collectively, the evidence indicates that both gross and net primary productivity has likely increased over recent decades, as have tree growth, recruitment, and mortality rates, and forest biomass. These results suggest a profound reorganization of tropical forest ecosystems. We evaluate the most likely drivers of the suite of changes, and suggest increasing resource availability, potentially from rising atmospheric CO(2) concentrations, is the most likely cause. | |||||
BibTeX:
@incollection{lewis_changing_2009, author = {Lewis, Simon L. and Lloyd, Jon and Sitch, Stephen and Mitchard, Edward T. A. and Laurance, William F.}, title = {Changing Ecology of Tropical Forests: Evidence and Drivers}, booktitle = {Annual Review of Ecology Evolution and Systematics}, year = {2009}, volume = {40}, pages = {529--549}, url = {://WOS:000272455700025}, doi = {https://doi.org/10.1146/annurev.ecolsys.39.110707.173345} } |
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Lewis, S.L., Brando, P.M., Phillips, O.L., van der Heijden, G.M.F. and Nepstad, D. | The 2010 Amazon Drought | 2011 | Science Vol. 331(6017), pp. 554-554 |
article | DOI URL |
Abstract: In 2010, dry-season rainfall was low across Amazonia, with apparent similarities to the major 2005 drought. We analyzed a decade of satellite-derived rainfall data to compare both events. Standardized anomalies of dry-season rainfall showed that 57% of Amazonia had low rainfall in 2010 as compared with 37% in 2005 (textless/=-1 standard deviation from long-term mean). By using relationships between drying and forest biomass responses measured for 2005, we predict the impact of the 2010 drought as 2.2 x 10(15) grams of carbon [95% confidence intervals (CIs) are 1.2 and 3.4], largely longer-term committed emissions from drought-induced tree deaths, compared with 1.6 x 10(15) grams of carbon (CIs 0.8 and 2.6) for the 2005 event. | |||||
BibTeX:
@article{lewis_2010_2011, author = {Lewis, Simon L. and Brando, Paulo M. and Phillips, Oliver L. and van der Heijden, Geertje M. F. and Nepstad, Daniel}, title = {The 2010 Amazon Drought}, journal = {Science}, year = {2011}, volume = {331}, number = {6017}, pages = {554--554}, note = {Edition: 2011/02/05}, url = {://WOS:000286933600045 http://www.sciencemag.org/content/331/6017/554}, doi = {https://doi.org/10.1126/science.1200807} } |
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Lewis, S.L. | Tropical forests and the changing earth system | 2006 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 361(1465), pp. 195-210 |
article | DOI URL |
Abstract: Tropical forests are global epicentres of biodiversity and important modulators of the rate of climate change. Recent research on deforestation rates and ecological changes within intact forests, both areas of recent research and debate, are reviewed, and the implications for biodiversity (species loss) and climate change (via the global carbon cycle) addressed. Recent impacts have most likely been: (i) a large source of carbon to the atmosphere, and major loss of species, from deforestation and (ii) a large carbon sink within remaining intact forest, accompanied by accelerating forest dynamism and widespread biodiversity changes. Finally, I look to the future, suggesting that the current carbon sink in intact forests is unlikely to continue, and that the tropical forest biome may even become a large net source of carbon, via one or more of four plausible routes: changing photosynthesis and respiration rates, biodiversity changes in intact forest, widespread forest collapse via drought, and widespread forest collapse via fire. Each of these scenarios risks potentially dangerous positive feedbacks with the climate system that could dramatically accelerate and intensify climate change. Given that continued land-use change alone is already thought to be causing the sixth mass extinction event in Earth's history, should such feedbacks occur, the resulting biodiversity and societal consequences would be even more severe. | |||||
BibTeX:
@article{lewis_tropical_2006, author = {Lewis, S. L.}, title = {Tropical forests and the changing earth system}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2006}, volume = {361}, number = {1465}, pages = {195--210}, note = {Edition: 2006/03/24}, url = {://WOS:000234928400013}, doi = {https://doi.org/10.1098/rstb.2005.1711} } |
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Levis, P., Schietti, J., Emilio, T., Pinto, J., Clement, C., Costa F.R.C., C. and Souza | Historical Human Footprint on Modern Tree Species Composition in the Purus-Madeira Interfluve, Central Amazonia [BibTeX] |
2012 | PLos ONE Vol. 7, pp. e48559 |
article | |
BibTeX:
@article{levis_historical_2012, author = {Levis, P.F.; Schietti, J.; Emilio, T.; Pinto, J.L.P.V.; Clement, C.R.; Costa, F.R.C., C.; Souza}, title = {Historical Human Footprint on Modern Tree Species Composition in the Purus-Madeira Interfluve, Central Amazonia}, journal = {PLos ONE}, year = {2012}, volume = {7}, pages = {e48559} } |
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Levine, J., MacKenzie, A., Squire, O., Archibald, A., Griffiths, P., Abraham, N., Pyle, J., Oram, D., Forster, G., Brito, J., Lee, J., Hopkins, J., Lewis, A., Bauguitte, S., Demarco, C., Artaxo, P., Messina, P. and Lathière, J. | Isoprene chemistry in pristine and polluted Amazon environments: Eulerian and Lagrangian model frameworks and the strong bearing they have on our understanding of surface ozone and predictions of rainforest exposure to this priority pollutant [BibTeX] |
2015 | Atmos. Chem. Phys. Discuss. Vol. 15, pp. 24251-24310 |
article | |
BibTeX:
@article{levine_isoprene_2015, author = {Levine, J.G. and MacKenzie, A.R. and Squire, O.J. and Archibald, A.T. and Griffiths, P.T. and Abraham, N.L. and Pyle, J.A. and Oram, D.E. and Forster, G. and Brito, J.F. and Lee, J.D. and Hopkins, J.R. and Lewis, A.C. and Bauguitte, S.J.B. and Demarco, C.F. and Artaxo, P. and Messina, P. and Lathière, J.}, title = {Isoprene chemistry in pristine and polluted Amazon environments: Eulerian and Lagrangian model frameworks and the strong bearing they have on our understanding of surface ozone and predictions of rainforest exposure to this priority pollutant}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2015}, volume = {15}, pages = {24251--24310} } |
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Leppla, D., Zannoni, N., Kremper, L., Williams, J., Pöhlker, C., Sá, M., Solci, M.C. and Hoffmann, T. | Varying chiral ratio of pinic acid enantiomers above the Amazon rainforest [BibTeX] |
2023 | Atmos. Chem. Phys. Vol. 23(2), pp. 809-820 |
article | DOI URL |
BibTeX:
@article{leppla_varying_2023, author = {Leppla, D. and Zannoni, N. and Kremper, L. and Williams, J. and Pöhlker, C. and Sá, M. and Solci, M. C. and Hoffmann, T.}, title = {Varying chiral ratio of pinic acid enantiomers above the Amazon rainforest}, journal = {Atmos. Chem. Phys.}, year = {2023}, volume = {23}, number = {2}, pages = {809--820}, url = {https://acp.copernicus.org/articles/23/809/2023/}, doi = {https://doi.org/10.5194/acp-23-809-2023} } |
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Leppla, D., Zannoni, N., Kremper, L., Williams, J., Pöhlker, C., Sá, M., Solci, M.C. and Hoffmann, T. | Varying chiral ratio of Pinic acid enantiomers above the Amazon rainforest [BibTeX] |
2021 | Atmos. Chem. Phys. Discuss. Vol. 2021, pp. 1-19 |
article | DOI URL |
BibTeX:
@article{leppla_varying_2021, author = {Leppla, D. and Zannoni, N. and Kremper, L. and Williams, J. and Pöhlker, C. and Sá, M. and Solci, M. C. and Hoffmann, T.}, title = {Varying chiral ratio of Pinic acid enantiomers above the Amazon rainforest}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2021}, volume = {2021}, pages = {1--19}, url = {https://acp.copernicus.org/preprints/acp-2021-150/}, doi = {https://doi.org/10.5194/acp-2021-150} } |
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Lennox, G., Gardner, T., Thomson, J., Ferreira, J., Berenguer, E., Lees, A., Nally, R., Aragão, L., Ferraz, S., Louzada, J., Moura, N., Oliveira, V., Pardini, R., Solar, R., Vaz‐de Mello, F., Vieira, I. and Barlow, J. | Second rate or a second chance? Assessing biomass and biodiversity recovery in regenerating Amazonian forests [BibTeX] |
2018 | Global Change Biology | article | DOI |
BibTeX:
@article{lennox_second_2018, author = {Lennox, G.D. and Gardner, T.A. and Thomson, J.R. and Ferreira, J. and Berenguer, E. and Lees, A.C. and Nally, R.M. and Aragão, L.E.O.C. and Ferraz, S.F.B. and Louzada, J. and Moura, N.G. and Oliveira, V.H.F. and Pardini, R. and Solar, R.R.C. and Vaz‐de Mello, F.Z. and Vieira, I.C.G and Barlow, J.}, title = {Second rate or a second chance? Assessing biomass and biodiversity recovery in regenerating Amazonian forests}, journal = {Global Change Biology}, year = {2018}, doi = {https://doi.org/10.1111/gcb.14443} } |
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Leitold, V., Morton, D.C., Longo, M., Santos, M.N.d., Keller, M. and Scaranello, M. | El Niño drought increased canopy turnover in Amazon forests [BibTeX] |
2018 | New Phytologist | article | DOI |
BibTeX:
@article{leitold_nino_2018, author = {Leitold, Veronika and Morton, Douglas C. and Longo, Marcos and Santos, Maiza Nara dos‐ and Keller, Michael and Scaranello, Marcos}, title = {El Niño drought increased canopy turnover in Amazon forests}, journal = {New Phytologist}, year = {2018}, doi = {https://doi.org/10.1111/nph.15110} } |
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Leitold, K., Morton, M., Cook, D.C., Shimabukuro, B.D. and V., Y.E. | Airborne lidar-based estimates of tropical forest structure in complex terrain: Opportunities and trade-offs for REDD+ [BibTeX] |
2015 | Carbon Balance and Management Vol. 10(3) |
article | DOI |
BibTeX:
@article{leitold_airborne_2015, author = {Leitold, Keller, M., Morton, D.C., Cook, B.D., Shimabukuro, Y.E., V.}, title = {Airborne lidar-based estimates of tropical forest structure in complex terrain: Opportunities and trade-offs for REDD+}, journal = {Carbon Balance and Management}, year = {2015}, volume = {10}, number = {3}, doi = {https://doi.org/10.1186/s13021-015-0013-x} } |
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Leite, R.G., Araujo-Lima, C., Victoria, R.L. and Martinelli, L.A. | Stable isotope analysis of energy sources for larvae of eight fish species from the Amazon floodplain | 2002 | Ecology of Freshwater Fish Vol. 11(1), pp. 56-63 |
article | DOI URL |
Abstract: Aquatic macrophytes form the most productive habitat of the Amazon floodplain and account for more than 60% of the net primary production of the ecosystem. Aquatic grasses are the dominant macrophytes and the main feeding ground of Amazonian larval fish. The present study used stable isotopes of nitrogen and carbon to measure the contribution of aquatic grasses to the production of eight larval fish, and describes the structure of the trophic chain. The carnivore larvae were at the third trophic level, and the detritivores were at the second and third trophic levels. The contribution of aquatic grasses to larval fish production was variable. It could reach a mean value of 25% for three species, but its contribution probably did not exceed 12% in the other five species. | |||||
BibTeX:
@article{leite_stable_2002, author = {Leite, R. G. and Araujo-Lima, Carm and Victoria, R. L. and Martinelli, L. A.}, title = {Stable isotope analysis of energy sources for larvae of eight fish species from the Amazon floodplain}, journal = {Ecology of Freshwater Fish}, year = {2002}, volume = {11}, number = {1}, pages = {56--63}, url = {://WOS:000174434000006}, doi = {https://doi.org/10.1034/j.1600-0633.2002.110106.x} } |
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Leite, N.K., Krusche, A.V., Cabianchi, G.M., Ballester, M.V.R., Victoria, R.L., Marchetto, M. and dos Santos, J.G. | Groundwater quality comparison between rural farms and riparian wells in the Western Amazon, Brazil | 2011 | Quimica Nova Vol. 34(1), pp. 11-U17 |
article | URL |
Abstract: Groundwater quality of a riparian forest is compared to wells in surrounding rural areas at Urupa River basin. Groundwater types were calcium bicarbonated at left margin and sodium chloride at right, whereas riparian wells exhibited a combination of both (sodium bicarbonate). Groundwater was mostly solute-depleted with concentrations within permissible limits for human consumption, except for nitrate. Isotopic composition suggests that inorganic carbon in Urupa River is mostly supplied by runoff instead of riparian groundwater. Hence, large pasture areas in addition to narrow riparian forest width in this watershed may have an important contribution in the chemical composition of this river. | |||||
BibTeX:
@article{leite_groundwater_2011, author = {Leite, Nei K. and Krusche, Alex V. and Cabianchi, Giovana M. and Ballester, Maria Victoria R. and Victoria, Reynaldo L. and Marchetto, Margarida and dos Santos, Judes G.}, title = {Groundwater quality comparison between rural farms and riparian wells in the Western Amazon, Brazil}, journal = {Quimica Nova}, year = {2011}, volume = {34}, number = {1}, pages = {11--U17}, url = {://WOS:000287140900003} } |
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Leite, N.K., Krusche, A.V., Ballester, M.V.R., Victoria, R.L., Richey, J.E. and Gomes, B.M. | Intra and interannual variability in the Madeira River water chemistry and sediment load | 2011 | Biogeochemistry Vol. 105(1-3), pp. 37-51 |
article | DOI URL |
Abstract: Concentrations of cations (Na(+), Ca(2+), Mg(2+), K(+), NH(4) (+)), anions (HCO(3) (-), Cl(-), NO(3) (-), SO(4) (2-), PO(4) (3-)) and suspended sediments in the Madeira River water were determined near the city of Porto Velho (RO), in order to assess variation in water chemistry from 2004 to 2007. Calcium and bicarbonate were the dominant cation and anion, respectively. Significant seasonal differences were found, with highest concentrations occurring during the dry season, as expected from the drainage of Andean carbonate-rich substratum. Interannual variations were also observed, but became significant only when annual average discharge was 25% less than normal. Under this atypical discharge condition, bicarbonate was replaced by sulfate, and higher suspended sediment concentrations and loads were also observed. Compared to previously published studies, it appears that no significant changes in water chemistry have occurred during the last 20-30 years, although differences in approaches and sampling designs among this and previous studies may not allow detection of modest changes. The calculated suspended sediment load reported here is close to the values presented elsewhere, reinforcing the relative importance of this river as a sediment supplier for the Amazon Basin. Seasonality has a significant control on the chemistry of Madeira River waters, and severe decrease in discharge due to anthropogenic changes, such as construction of reservoirs or the occurrence of drier years-a plausible consequence of global climate change-may lead to modification in the chemical composition as well in the sediment deliver to the Amazon River. | |||||
BibTeX:
@article{leite_intra_2011, author = {Leite, Nei K. and Krusche, Alex V. and Ballester, Maria V. R. and Victoria, Reynaldo L. and Richey, Jeffrey E. and Gomes, Beatriz M.}, title = {Intra and interannual variability in the Madeira River water chemistry and sediment load}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {37--51}, url = {://WOS:000294501100004}, doi = {https://doi.org/10.1007/s10533-010-9568-5} } |
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Lehmann, J. | Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy for mapping nano-scale distribution of organic carbon forms in soil: Application to black carbon particles | 2005 | Global Biogeochemical Cycles Vol. 19(1) |
article | DOI URL |
Abstract: 1] Small-scale heterogeneity of organic carbon (C) forms in soils is poorly quantified since appropriate analytical techniques were not available up to now. Specifically, tools for the identification of functional groups on the surface of micrometer-sized black C particles were not available up to now. Scanning Transmission X-ray Microscopy ( STXM) using synchrotron radiation was used in conjunction with Near- Edge X-ray Absorption Fine Structure ( NEXAFS) spectroscopy to investigate nano- scale distribution ( 50-nm resolution) of C forms in black C particles and compared to synchrotron-based FTIR spectroscopy. A new embedding technique was developed that did not build on a C-based embedding medium and did not pose the risk of heat damage to the sample. Elemental sulfur (S) was melted to 220 degreesC until it polymerized and quenched with liquid N(2) to obtain a very viscous plastic S in which the black C could be embedded until it hardened to a noncrystalline state and was ultrasectioned. Principal component and cluster analysis followed by singular value decomposition was able to resolve distinct areas in a black carbon particle. The core of the studied biomass-derived black C particles was highly aromatic even after thousands of years of exposure in soil and resembled the spectral characteristics of fresh charcoal. Surrounding this core and on the surface of the black C particle, however, much larger proportions of carboxylic and phenolic C forms were identified that were spatially and structurally distinct from the core of the particle. Cluster analysis provided evidence for both oxidation of the black C particle itself as well as adsorption of non-black C. NEXAFS spectroscopy has great potential to allow new insight into black C properties with important implications for biogeochemical cycles such as mineralization of black C in soils and sediments, and adsorption of C, nutrients, and pollutants as well as transport in the geosphere, hydrosphere, and atmosphere. | |||||
BibTeX:
@article{lehmann_near-edge_2005, author = {Lehmann, J.}, title = {Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy for mapping nano-scale distribution of organic carbon forms in soil: Application to black carbon particles}, journal = {Global Biogeochemical Cycles}, year = {2005}, volume = {19}, number = {1}, url = {://WOS:000227213400002}, doi = {https://doi.org/10.1029/2004gb002435} } |
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Lefsky, M.A., Keller, M., Pang, Y., de Camargo, P.B. and Hunter, M.O. | Revised method for forest canopy height estimation from Geoscience Laser Altimeter System waveforms | 2007 | Journal of Applied Remote Sensing Vol. 1 |
article | DOI URL |
Abstract: The vertical extent of waveforms collected by the Geoscience Laser Altimeter System (onboard ICESat - the Ice, Cloud, and land Elevation Satellite) increases as a function of terrain slope and footprint size (the area on the ground that is illuminated by the laser). Over sloped terrain, returns from both canopy and ground surfaces can occur at the same elevation. As a result, the height of the waveform (waveform extent) is insufficient to make estimates of tree height on sloped terrain, and algorithms are needed that are capable of retrieving information about terrain slope from the waveform itself. Early work on this problem used a combination of waveform height indices and slope indices from a digital elevation model (DEM). A second generation algorithm was developed using datasets from diverse forests in which forest canopy height has been estimated in the field or by via airborne lidar. Forest types considered in this paper include evergreen needleleaf, deciduous broadleaf and mixed stands in temperate North America, and tropical evergreen broadleaf forests in Brazil. The algorithm described eliminates the need for a DEM, and estimates forest canopy height with an RMSE of 5 m (83% of variance in forest canopy height explained). | |||||
BibTeX:
@article{lefsky_revised_2007, author = {Lefsky, Michael A. and Keller, Michael and Pang, Yong and de Camargo, Plinio B. and Hunter, Maria O.}, title = {Revised method for forest canopy height estimation from Geoscience Laser Altimeter System waveforms}, journal = {Journal of Applied Remote Sensing}, year = {2007}, volume = {1}, url = {://WOS:000260914300013}, doi = {https://doi.org/10.1117/1.2795724} } |
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Lefsky, M.A., Harding, D.J., Keller, M., Cohen, W.B., Carabajal, C.C., Espirito-Santo, F.D., Hunter, M.O. and de Oliveira, R. | Estimates of forest canopy height and aboveground biomass using ICESat | 2005 | Geophysical Research Letters Vol. 32(22) |
article | DOI URL |
Abstract: Exchange of carbon between forests and the atmosphere is a vital component of the global carbon cycle. Satellite laser altimetry has a unique capability for estimating forest canopy height, which has a direct and increasingly well understood relationship to aboveground carbon storage. While the Geoscience Laser Altimeter System (GLAS) onboard the Ice, Cloud and land Elevation Satellite (ICESat) has collected an unparalleled dataset of lidar waveforms over terrestrial targets, processing of ICESat data to estimate forest height is complicated by the pulse broadening associated with large-footprint, waveform-sampling lidar. We combined ICESat waveforms and ancillary topography from the Shuttle Radar Topography Mission to estimate maximum forest height in three ecosystems; tropical broadleaf forests in Brazil, temperate broadleaf forests in Tennessee, and temperate needleleaf forests in Oregon. Final models for each site explained between 59% and 68% of variance in field-measured forest canopy height (RMSE between 4.85 and 12.66 m). In addition, ICESat-derived heights for the Brazilian plots were correlated with field-estimates of aboveground biomass (r(2) = 73%, RMSE = 58.3 Mgha(-1)). | |||||
BibTeX:
@article{lefsky_estimates_2005, author = {Lefsky, M. A. and Harding, D. J. and Keller, M. and Cohen, W. B. and Carabajal, C. C. and Espirito-Santo, F. D. and Hunter, M. O. and de Oliveira, R.}, title = {Estimates of forest canopy height and aboveground biomass using ICESat}, journal = {Geophysical Research Letters}, year = {2005}, volume = {32}, number = {22}, url = {://WOS:000233160100001}, doi = {https://doi.org/10.1029/2005gl023971} } |
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Lee, Y.H. and Adams, P.J. | Evaluation of aerosol distributions in the GISS-TOMAS global aerosol microphysics model with remote sensing observations | 2010 | Atmospheric Chemistry and Physics Vol. 10(5), pp. 2129-2144 |
article | URL |
Abstract: The Aerosol Optical Depth (AOD) and Angstrom Coefficient (AC) predictions in the GISS-TOMAS model of global aerosol microphysics are evaluated against remote sensing data from MODIS, MISR, and AERONET. The model AOD agrees well (within a factor of two) over polluted continental (or high sulfate), dusty, and moderate sea-salt regions but less well over the equatorial, high sea-salt, and biomass burning regions. Underprediction of sea-salt in the equatorial region is likely due to GCM meteorology (low wind speeds and high precipitation). For the Southern Ocean, overprediction of AOD is very likely due to high sea-salt emissions and perhaps aerosol water uptake in the model. However, uncertainties in cloud screening at high latitudes make it difficult to evaluate the model AOD there with the satellite-based AOD. AOD in biomass burning regions is underpredicted, a tendency found in other global models but more severely here. Using measurements from the LBA-SMOCC 2002 campaign, the surface-level OC concentration in the model are found to be underpredicted severely during the dry season while much less severely for EC concentration, suggesting the low AOD in the model is due to underpredictions in OM mass. The potential for errors in emissions and wet deposition to contribute to this bias is discussed. | |||||
BibTeX:
@article{lee_evaluation_2010, author = {Lee, Y. H. and Adams, P. J.}, title = {Evaluation of aerosol distributions in the GISS-TOMAS global aerosol microphysics model with remote sensing observations}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {5}, pages = {2129--2144}, url = {://WOS:000275505500004} } |
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L'Ecuyer, T.S., Kummerow, C. and Berg, W. | Toward a global map of raindrop size distributions. Part I: Rain-type classification and its implications for validating global rainfall products | 2004 | Journal of Hydrometeorology Vol. 5(5), pp. 831-849 |
article | DOI URL |
Abstract: Variability in the global distribution of precipitation is recognized as a key element in assessing the impact of climate change for life on earth. The response of precipitation to climate forcings is, however, poorly understood because of discrepancies in the magnitude and sign of climatic trends in satellite-based rainfall estimates. Quantifying and ultimately removing these biases is critical for studying the response of the hydrologic cycle to climate change. In addition, estimates of random errors owing to variability in algorithm assumptions on local spatial and temporal scales are critical for establishing how strongly their products should be weighted in data assimilation or model validation applications and for assigning a level of confidence to climate trends diagnosed from the data. This paper explores the potential for refining assumed drop size distributions (DSDs) in global radar rainfall algorithms by establishing a link between satellite observables and information gleaned from regional validation experiments where polarimetric radar, Doppler radar, and disdrometer measurements can be used to infer raindrop size distributions. By virtue of the limited information available in the satellite retrieval framework, the current method deviates from approaches adopted in the ground-based radar community that attempt to relate microphysical processes and resultant DSDs to local meteorological conditions. Instead, the technique exploits the fact that different microphysical pathways for rainfall production are likely to lead to differences in both the DSD of the resulting raindrops and the three-dimensional structure of associated radar reflectivity profiles. Objective rain-type classification based on the complete three-dimensional structure of observed reflectivity profiles is found to partially mitigate random and systematic errors in DSDs implied by differential reflectivity measurements. In particular, it is shown that vertical and horizontal reflectivity structure obtained from spaceborne radar can be used to reproduce significant differences in Z(dr) between the easterly and westerly climate regimes observed in the Tropical Rainfall Measuring Mission Large-scale Biosphere - Atmosphere (TRMM-LBA) field experiment as well as the even larger differences between Amazonian rainfall and that observed in eastern Colorado. As such, the technique offers a potential methodology for placing locally observed DSD information into a global framework. |
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BibTeX:
@article{lecuyer_toward_2004, author = {L'Ecuyer, T. S. and Kummerow, C. and Berg, W.}, title = {Toward a global map of raindrop size distributions. Part I: Rain-type classification and its implications for validating global rainfall products}, journal = {Journal of Hydrometeorology}, year = {2004}, volume = {5}, number = {5}, pages = {831--849}, url = {://WOS:000224847400010}, doi = {https://doi.org/10.1175/1525-7541(2004)005%3C0831:tagmor%3E2.0.co;2} } |
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Leal, C., R.L.C., L., Ribeiro, B.G. and L.S.M., A. | Variação Diurna da Concentração de CO2 no dossel Vegetativo da Floresta Amazônica em Caixiuanã-PA [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 122-128 |
article | |
BibTeX:
@article{leal_variacao_2006, author = {Leal, Carneiro, R.L.C., Leal, B.G., Ribeiro, A., L.S.M.}, title = {Variação Diurna da Concentração de CO2 no dossel Vegetativo da Floresta Amazônica em Caixiuanã-PA}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {122--128} } |
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Le Page, Y., van der Werf, G.R., Morton, D.C. and Pereira, J.M.C. | Modeling fire-driven deforestation potential in Amazonia under current and projected climate conditions | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115(G03012), pp. doi:10.1029/2009JG001190 |
article | DOI URL |
Abstract: Fire is a widely used tool to prepare deforested areas for agricultural use in Amazonia. Deforestation is currently concentrated in seasonal forest types along the 'arc of deforestation', where dry-season conditions facilitate burning of clear-felled vegetation. Interior Amazon forests, however, are less suitable for fire-driven deforestation due to more humid climate conditions. These forests will ultimately come under more intense pressure as the deforestation frontier advances. Whether these regions continue to be protected by humid conditions partly determines land use changes in interior Amazon forests. Here, we present a study of the climate constraint on deforestation fires in Amazonia under present-day and projected climate conditions. We used precipitation data and satellite-based active fire detections to model fire-driven deforestation potential. Our model results suggest that 58% of the Amazon forest is too wet to permit fire-driven deforestation under current average climate conditions. Under the IPCC B1 scenario, the model indicates increased fire potential by 2050 in eastern Amazonia, while dry-season precipitation may provide limitations on projected deforestation by 2050 in central and western Amazonia. However, the entire region is very sensitive to a possible drying with climate change; a reduction in dry-season precipitation of 200 mm/year would reduce the climate constraint on deforestation fires from 58% to only 24% of the forest. Our results suggest that dry-season climate conditions will continue to shape land use decisions in Amazonia through mid-century, and should therefore be included in deforestation projections for the region. | |||||
BibTeX:
@article{le_page_modeling_2010, author = {Le Page, Y. and van der Werf, G. R. and Morton, D. C. and Pereira, J. M. C.}, title = {Modeling fire-driven deforestation potential in Amazonia under current and projected climate conditions}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, number = {G03012}, pages = {doi:10.1029/2009JG001190}, url = {://000280719100002}, doi = {https://doi.org/10.1029/2009jg001190} } |
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Laurent, H., Machado, L.A.T., Morales, C.A. and Durieux, L. | Characteristics of the Amazonian mesoscale convective systems observed from satellite and radar during the WETAMC/LBA experiment | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: An objective tracking of mesoscale convective systems (MCSs) observed in full-resolution Geostationary Operational Environmental Satellite (GOES) satellite images has been applied during the Wet Season Atmospheric Mesoscale Campaign/Large-Scale Biosphere-Atmosphere (WETAMC/LBA) experiment in Amazonia from January to February 1999 to document the characteristics of the convective cloud organization in the southwestern Amazon region. The same tracking methodology was also applied to the National Aeronautical Space Administration (NASA) Tropical Ocean Global Atmosphere (TOGA) C-Band radar data in order to estimate the propagation of the convective rain cells from constant altitude plan position indicators (CAPPI) at a height of 2 km. The convective activity showed two different patterns named Easterly and Westerly regimes according to the wind flow in the 700-850-hPa layer. During the Easterly regime, MCSs and rain cells had closely related propagations. MCS as well as rain cell propagations were associated mostly to the midlevel mean flow. During the Westerly regime, the propagations of both MCSs and rain cells were much more disorganized, there was no clear relationship with the mean atmospheric flow at any level, although the rain cells have a slight tendency to propagate eastward, and the low-level rain cells propagated quite independently of the high-level cloud cover. MCS initiations were mostly driven by topography, that is, high escarpment and relatively high elevation. | |||||
BibTeX:
@article{laurent_characteristics_2002, author = {Laurent, H. and Machado, L. A. T. and Morales, C. A. and Durieux, L.}, title = {Characteristics of the Amazonian mesoscale convective systems observed from satellite and radar during the WETAMC/LBA experiment}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200011 http://www.agu.org/journals/jd/jd0217/2001JD000337/2001JD000337.pdf}, doi = {https://doi.org/10.1029/2001jd000337} } |
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Laurent Arai, N., Fomin, B. and Machado L.A.T. & Gondim, M.H. | Extração do vento utilizando imagens de satélite no CPTEC: Nova versão e avaliação com dados do LBA e dados operacionais da DSA/CPTEC [BibTeX] |
2002 | Revista Brasileira de Meteorologia Vol. 17, pp. 113-123 |
article | |
BibTeX:
@article{laurent_extracao_2002, author = {Laurent, Arai, N.; Fomin, B.; Machado, L.A.T. & Gondim, M.A., H.}, title = {Extração do vento utilizando imagens de satélite no CPTEC: Nova versão e avaliação com dados do LBA e dados operacionais da DSA/CPTEC}, journal = {Revista Brasileira de Meteorologia}, year = {2002}, volume = {17}, pages = {113--123} } |
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Laurence, W.F. and Fearnside, P.M. | Issues in Amazonian development [BibTeX] |
2002 | Science Vol. 295(5560), pp. 1643-1643 |
article | URL |
BibTeX:
@article{laurence_issues_2002, author = {Laurence, W. F. and Fearnside, P. M.}, title = {Issues in Amazonian development}, journal = {Science}, year = {2002}, volume = {295}, number = {5560}, pages = {1643--1643}, url = {://WOS:000174212900019} } |
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Laurance, W.F., Williamson, G.B., Delamonica, P., Oliveira, A., Lovejoy, T.E., Gascon, C. and Pohl, L. | Effects of a strong drought on Amazonian forest fragments and edges | 2001 | Journal of Tropical Ecology Vol. 17, pp. 771-785 |
article | URL |
Abstract: Little is known about how climatic variability affects fragmented forests and their abrupt edges. We contrasted effects of the 1997 El Nino drought between fragmented and continuous forests in central Amazonia, using long-term data on tree mortality. For 23 permanent 1-ha plots, annualized mortality rates of trees greater than or equal to 10 cm diameter at breast height (dbh) were compared among a 'baseline' interval of 5-17 N, before the drought, a 12-16-month inter-Val during the drought, and a 12-13-month interval after the drought, using repeated-measures ANOVA. We also examined the size distributions of dead trees for each interval. During the drought, average annual tree mortality rose significantly in both forest edges (from 2.44% to 2.93%) and interiors (from 1.13% to 1.91%), and the magnitude of this increase did not differ significantly between edges and interiors. After the drought, tree mortality declined in all plots, but most dramatically on edges. Mortality rates were more Variable over time on edges than interiors, and there was no evidence of time lags in mortality. In forest interiors, the size distributions of trees that died did not differ significantly among the three intervals. On edges, however, relatively fewer small (10-15 cm dbh) and more medium-sized (20-30 cm dbh) trees died in the post-drought interval, compared to other intervals. Moreover, forest edges lost a significantly higher proportion of large (greater than or equal to 60 cm dbh) trees than did forest interiors. These results suggest that droughts have relatively complex effects on fragmented Amazonian forests. Drought effects in our forest fragments probably were reduced by prior floristic and structural changes near edges and by adjoining regrowth forest that partially buffered edge vegetation from desiccating conditions. | |||||
BibTeX:
@article{laurance_effects_2001, author = {Laurance, W. F. and Williamson, G. B. and Delamonica, P. and Oliveira, A. and Lovejoy, T. E. and Gascon, C. and Pohl, L.}, title = {Effects of a strong drought on Amazonian forest fragments and edges}, journal = {Journal of Tropical Ecology}, year = {2001}, volume = {17}, pages = {771--785}, url = {://WOS:000172660900001} } |
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Laurance, W.F. and Williamson, G.B. | Positive feedbacks among forest fragmentation, drought, and climate change in the Amazon | 2001 | Conservation Biology Vol. 15(6), pp. 1529-1535 |
article | DOI URL |
Abstract: The Amazon basin is experiencing rapid forest loss and fragmentation, Fragmented forests are more prone than intact forests to periodic damage from El Nino-Southern Oscillation (ENSO) droughts, which cause elevated tree mortality, increased litterfall, shifts in plant phenology, and other ecological changes, especially near forest edges, Moreover, positive feedbacks among forest loss, fragmentation, fire, and regional climate change appear increasingly likely Deforestation reduces plant evapotranspiration, which in turn constrains regional rainfall, increasing the vulnerability of forests to fire. Forest fragments are especially vulnerable because they have dry, fire-prone edges, are logged frequently, and often are adjoined by cattle pastures, which are burned regularly. The net result is that there may be a critical "deforestation threshold" above which Amazonian rainforests can no longer be sustained, particularly in relatively seasonal areas of the basin. Global warming could exacerbate this problem if it promotes drier climates or stronger ENSO droughts. Synergisms among many simultaneous environmental changes are posing unprecedented threats to Amazonian forests. | |||||
BibTeX:
@article{laurance_positive_2001, author = {Laurance, W. F. and Williamson, G. B.}, title = {Positive feedbacks among forest fragmentation, drought, and climate change in the Amazon}, journal = {Conservation Biology}, year = {2001}, volume = {15}, number = {6}, pages = {1529--1535}, url = {://WOS:000172692900012}, doi = {https://doi.org/10.1046/j.1523-1739.2001.01093.x} } |
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Laurance, W.F., Vasconcelos, H.L. and Lovejoy, T.E. | Forest loss and fragmentation in the Amazon: implications for wildlife conservation | 2000 | Oryx Vol. 34(1), pp. 39-45 |
article | DOI URL |
Abstract: Amazonian forests are experiencing rapid, unprecedented changes that are having major impacts on wildlife, regional hydrology and the global climate. Rates of deforestation and logging have accelerated in recent years and patterns of forest loss are changing, with extensive new highways providing conduits for settlers and loggers into the heart of the Amazon basin. These myriad changes are causing widespread fragmentation of forests. Fragmented landscapes in the Amazon experience diverse changes in forest dynamics, structure, composition and microclimate, and are highly vulnerable to droughts and fires-alterations that negatively affect a wide variety of animal species. Ln human-dominated lands intensive hunting may interact synergistically with fragmentation to further threaten wildlife populations. | |||||
BibTeX:
@article{laurance_forest_2000, author = {Laurance, W. F. and Vasconcelos, H. L. and Lovejoy, T. E.}, title = {Forest loss and fragmentation in the Amazon: implications for wildlife conservation}, journal = {Oryx}, year = {2000}, volume = {34}, number = {1}, pages = {39--45}, url = {://WOS:000085366300008}, doi = {https://doi.org/10.1046/j.1365-3008.2000.00094.x} } |
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Laurance, W.F., Perez-Salicrup, D., Delamonica, P., Fearnside, P.M., D'Angelo, S., Jerozolinski, A., Pohl, L. and Lovejoy, T.E. | Rain forest fragmentation and the structure of Amazonian liana communities | 2001 | Ecology Vol. 82(1), pp. 105-116 |
article | DOI URL |
Abstract: In tropical forests, lianas (woody vines) are important structural parasites of trees. We assessed the effects of forest fragmentation, treefall disturbance, soils, and stand attributes on liana communities in central Amazonian rain forests. Over 27 500 liana stems (greater than or equal to2 cm diameter at breast height [dbh]) were recorded in 27 1-ha plots in continuous forest and 42 plots in 10 forest fragments ranging from 1 to 100 ha in area. For each plot, an index of forest disturbance was determined from a 20-yr study of tree-community dynamics, and 19 soil-texture and chemistry parameters were derived from soil surface samples (top 20 cm). Liana abundance was 187-701 stems/ha, and liana aboveground dry biomass varied from 3.7 to 12.3 Mg/ha. Liana abundance increased significantly near forest edges and was significantly positively associated with forest disturbance and significantly negatively associated with tree biomass. Liana biomass was similarly associated with disturbance and tree biomass but also increased significantly along soil-fertility gradients. Plots near forest edges had a significantly higher proportion of small (2-3 c-m dbh) lianas and relatively fewer large (greater than or equal to4 cm dbh) lianas than did sites in forest interiors. Liana communities were further assessed by comparing their species richness, composition, climbing guilds, and frequency of tree infestation in three 10-ha fragments. Within each fragment, data were collected in 24 small (400-m(2)) plots, with half of the plots near edges and half in interiors. Significantly more trees were infested on fragment edges than in interiors. All three major guilds (branch-twiners, mainstem-twiners, tendril-twiners) were significantly more abundant on edges. Species diversity of lianas (as measured by Fisher's diversity index) also was significantly higher on edges, and this was not simply an artifact of increased liana abundance on edges. We conclude that many aspects of liana community structure are affected by habitat fragmentation, and we suggest that lianas can have important impacts on forest dynamics and functioning in fragmented rain forests. By creating physical stresses on trees and competing for light and nutrients, heavy liana infestations appear partly responsible for the dramatically elevated rates of tree mortality and damage observed near fragment edges. |
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BibTeX:
@article{laurance_rain_2001, author = {Laurance, W. F. and Perez-Salicrup, D. and Delamonica, P. and Fearnside, P. M. and D'Angelo, S. and Jerozolinski, A. and Pohl, L. and Lovejoy, T. E.}, title = {Rain forest fragmentation and the structure of Amazonian liana communities}, journal = {Ecology}, year = {2001}, volume = {82}, number = {1}, pages = {105--116}, url = {://WOS:000166488200009}, doi = {https://doi.org/10.1890/0012-9658(2001)082%5B0105:rffats%5D2.0.co;2} } |
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Laurance, W.F., Oliveira, A.A., Laurance, S.G., Condit, R., Nascimento, H.E.M., Sanchez-Thorin, A.C., Lovejoy, T.E., Andrade, A., D'Angelo, S., Ribeiro, J.E. and Dick, C.W. | Pervasive alteration of tree communities in undisturbed Amazonian forests | 2004 | Nature Vol. 428(6979), pp. 171-175 |
article | DOI URL |
Abstract: Amazonian rainforests are some of the most species-rich tree communities on earth(1). Here we show that, over the past two decades, forests in a central Amazonian landscape have experienced highly nonrandom changes in dynamics and composition. Our analyses are based on a network of 18 permanent plots unaffected by any detectable disturbance. Within these plots, rates of tree mortality, recruitment and growth have increased over time. Of 115 relatively abundant tree genera, 27 changed significantly in population density or basal area-a value nearly 14 times greater than that expected by chance. An independent, eight-year study in nearby forests corroborates these shifts in composition. Contrary to recent predictions(2-5), we observed no increase in pioneer trees. However, genera of faster-growing trees, including many canopy and emergent species, are increasing in dominance or density, whereas genera of slower-growing trees, including many subcanopy species, are declining. Rising atmospheric CO2 concentrations(6) may explain these changes, although the effects of this and other large-scale environmental alterations remain uncertain. These compositional changes could have important impacts on the carbon storage, dynamics and biota of Amazonian forests. | |||||
BibTeX:
@article{laurance_pervasive_2004, author = {Laurance, W. F. and Oliveira, A. A. and Laurance, S. G. and Condit, R. and Nascimento, H. E. M. and Sanchez-Thorin, A. C. and Lovejoy, T. E. and Andrade, A. and D'Angelo, S. and Ribeiro, J. E. and Dick, C. W.}, title = {Pervasive alteration of tree communities in undisturbed Amazonian forests}, journal = {Nature}, year = {2004}, volume = {428}, number = {6979}, pages = {171--175}, note = {Edition: 2004/03/12}, url = {://WOS:000220103600046}, doi = {https://doi.org/10.1038/nature02383} } |
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Laurance, W.F., Oliveira, A.A., Laurance, S.G., Condit, R., Dick, C.W., Andrade, A., Nascimento, H.E.M., Lovejoy, T.E. and Ribeiro, J. | Altered tree communities in undisturbed Amazonian forests: A consequence of global change? [BibTeX] |
2005 | Biotropica Vol. 37(2), pp. 160-162 |
article | DOI URL |
BibTeX:
@article{laurance_altered_2005, author = {Laurance, W. F. and Oliveira, A. A. and Laurance, S. G. and Condit, R. and Dick, C. W. and Andrade, A. and Nascimento, H. E. M. and Lovejoy, T. E. and Ribeiro, Jels}, title = {Altered tree communities in undisturbed Amazonian forests: A consequence of global change?}, journal = {Biotropica}, year = {2005}, volume = {37}, number = {2}, pages = {160--162}, url = {://WOS:000229355500002 http://onlinelibrary.wiley.com/store/10.1111/j.1744-7429.2005.00022.x/asset/j.1744-7429.2005.00022.x.pdf?v=1&t=h6hwhnmb&s=137e84b869becc14af99b30c0224165320737b93}, doi = {https://doi.org/10.1111/j.1744-7429.2005.00022.x} } |
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Laurance, W.F., Nascimento, H.E.M., Laurance, S.G., Condit, R., D'Angelo, S. and Andrade, A. | Inferred longevity of Amazonian rainforest trees based on a long-term demographic study | 2004 | Forest Ecology and Management Vol. 190(2-3), pp. 131-143 |
article | DOI URL |
Abstract: We used data from a long-term (14-18 years) demographic study to infer the maximum longevity for populations of 93 relatively abundant tree species in central Amazonia. We also assessed the influence of several life-history features (wood density, growth form, mortality rate, recruitment rate, stem diameter, growth increment, population density) on tree longevity. Data on 3159 individual trees were collected in 24 permanent, 1 ha plots in undisturbed forest arrayed across a large (ca. 1000 km(2)) study area. For each species, three estimates of longevity were generated (by dividing the stem diameter of the largest tree by the median, upper quartile, and upper decile of observed diameter-growth rates), and the mean of these three values was used as a longevity estimate. Longevity values ranged from 48 years in the pioneer Pourouma bicolor (Cecropiaceae) to 981 years for the canopy tree Pouteria manaosensis (Sapotaceae), with an overall mean of 336 +/- 196 years. These growth-based estimates of maximum tree age were concordant with those derived from analyses of mean mortality rates. Tree longevity was positively correlated with wood density, maximum stem diameter, and population density, and negatively correlated with annual mortality, recruitment, and growth rates. On average, pioneer species had much lower longevity than did non-pioneers, whereas among old-growth trees, emergent species had greater longevity than did canopy species. Our results are consistent with radiocarbon-based studies that suggest that Amazonian trees can occasionally exceed 1000 years of age. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{laurance_inferred_2004, author = {Laurance, W. F. and Nascimento, H. E. M. and Laurance, S. G. and Condit, R. and D'Angelo, S. and Andrade, A.}, title = {Inferred longevity of Amazonian rainforest trees based on a long-term demographic study}, journal = {Forest Ecology and Management}, year = {2004}, volume = {190}, number = {2-3}, pages = {131--143}, url = {://WOS:000220456200002}, doi = {https://doi.org/10.1016/j.foreco.2003.09.011} } |
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Laurance, W.F., Nascimento, H.E.M., Laurance, S.G., Andrade, A.C., Fearnside, P.M., Ribeiro, J.E.L. and Capretz, R.L. | Rain forest fragmentation and the proliferation of successional trees | 2006 | Ecology Vol. 87(2), pp. 469-482 |
article | DOI URL |
Abstract: The effects of habitat fragmentation on diverse tropical tree communities are poorly understood. Over a 20-year period we monitored the density of 52 tree species in nine predominantly Successional genera (Annona, Bellucia, Cecropia, Croton, Goupia, Jacaranada, Miconia, Pourouma, Vismia) in fragmented and continuous Amazonian forests. We also evaluated the relative importance of soil, topographic, forest dynamic, and landscape variables in explaining the abundance and species composition of successional trees. Data were collected within 66 permanent 1-ha plots within a large (similar to 1000 km(2)) experimental landscape, with forest fragments ranging from 1 to 100 ha in area. Prior to forest fragmentation, successional trees were uncommon, typically comprising 2-3% of all trees (textgreater= 10 cm diameter at breast height [1.3 m above the ground surface]) in each plot. Following fragmentation, the density and basal area of successional trees increased rapidly. By 13-17 years after fragmentation, successional trees had tripled in abundance in fragment and edge plots and constituted more than a quarter of all trees in some plots. Fragment age had strong, positive effects on the density and basal area of successional trees, with no indication of a plateau in these variables, suggesting that successional species could become even more abundant in fragments over time. Nonetheless, the 52 species differed greatly in their responses to fragmentation and forest edges. Some disturbance-favoring pioneers (e.g., Cecropia sciadophylla, Vismia guianensis, V. amazonica, V. bemerguii, Miconia cf. crassinervia) increased by textgreater 1000% in density on edge plots, whereas over a third (19 of 52) of all species remained constant or declined in numbers. Species responses to fragmentation were effectively predicted by their median growth rate in nearby intact forest, suggesting that faster-growing species have a strong advantage in forest fragments. An ordination analysis revealed three main gradients in successional-species composition across our study area. Species gradients were most strongly influenced by the stand-level rate of tree mortality on each plot and by the number of nearby forest edges. Species composition also varied significantly among different cattle ranches, which differed in their Surrounding matrices and disturbance histories. These same variables were also the best predictors of total successional-tree abundance and species richness. Successional-tree assemblages in fragment interior plots (textgreater 150 m from edge), which are subjected to fragment area effects but not edge effects, did not differ significantly from those in intact forest, indicating that area effects per se had little influence on Successional trees. Soils and topography also had little discernable effect on these species. Collectively, our results indicate that successional-tree species proliferate rapidly in fragmented Amazonian forests, largely as a result of chronically elevated tree mortality near forest edges and possibly an increased seed rain from successional plants growing in nearby degraded habitats. The proliferation of fast-growing successional trees and correlated decline of old-growth trees will have important effects on species composition, forest dynamics, carbon storage, and nutrient cycling in fragmented forests. | |||||
BibTeX:
@article{laurance_rain_2006, author = {Laurance, W. F. and Nascimento, H. E. M. and Laurance, S. G. and Andrade, A. C. and Fearnside, P. M. and Ribeiro, J. E. L. and Capretz, R. L.}, title = {Rain forest fragmentation and the proliferation of successional trees}, journal = {Ecology}, year = {2006}, volume = {87}, number = {2}, pages = {469--482}, note = {Edition: 2006/04/28}, url = {://WOS:000236215400022}, doi = {https://doi.org/10.1890/05-0064} } |
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Laurance, W.F., Nascimento, H.E.M., Laurance, S.G., Andrade, A., Ribeiro, J.E.L.S., Giraldo, J.P., Lovejoy, T.E., Condit, R., Chave, J., Harms, K.E. and D'Angelo, S. | Rapid decay of tree-community composition in Amazonian forest fragments | 2006 | Proceedings of the National Academy of Sciences of the United States of America Vol. 103(50), pp. 19010-19014 |
article | DOI URL |
Abstract: Forest fragmentation is considered a greater threat to vertebrates than to tree communities because individual trees are typically long-lived and require only small areas for survival. Here we show that forest fragmentation provokes surprisingly rapid and profound alterations in Amazonian tree-community composition. Results were derived from a 22-year study of exceptionally diverse tree communities in 40 1-ha plots in fragmented and intact forests, which were sampled repeatedly before and after fragment isolation. Within these plots, trajectories of change in abundance were assessed for 267 genera and 1,162 tree species. Abrupt shifts in floristic composition were driven by sharply accelerated tree mortality and recruitment within approximate to 100 m of fragment margins, causing rapid species turnover and population declines or local extinctions of many large-seeded, slow-growing, and old-growth taxa; a striking increase in a smaller set of disturbance-adapted and abiotically dispersed species; and significant shifts in tree size distributions. Even among old-growth trees, species composition in fragments is being restructured substantially, with subcanopy species that rely on animal seed-dispersers and have obligate outbreeding being the most strongly disadvantaged. These diverse changes in tree communities are likely to have wide-ranging impacts on forest architecture, canopy-gap dynamics, plant-animal interactions, and forest carbon storage. | |||||
BibTeX:
@article{laurance_rapid_2006, author = {Laurance, William F. and Nascimento, Henrique E. M. and Laurance, Susan G. and Andrade, Ana and Ribeiro, Jose E. L. S. and Giraldo, Juan Pablo and Lovejoy, Thomas E. and Condit, Richard and Chave, Jerome and Harms, Kyle E. and D'Angelo, Sammya}, title = {Rapid decay of tree-community composition in Amazonian forest fragments}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2006}, volume = {103}, number = {50}, pages = {19010--19014}, note = {Edition: 2006/12/07}, url = {://WOS:000242884200026}, doi = {https://doi.org/10.1073/pnas.0609048103} } |
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Laurance, W.F., Nascimento, H.E.M., Laurance, S.G., Andrade, A., Ewers, R.M., Harms, K.E., Luizao, R.C.C. and Ribeiro, J.E. | Habitat Fragmentation, Variable Edge Effects, and the Landscape-Divergence Hypothesis | 2007 | PLos ONE Vol. 2(10), pp. e1017 |
article | DOI URL |
Abstract: Edge effects are major drivers of change in many fragmented landscapes, but are often highly variable in space and time. Here we assess variability in edge effects altering Amazon forest dynamics, plant community composition, invading species, and carbon storage, in the world's largest and longest-running experimental study of habitat fragmentation. Despite detailed knowledge of local landscape conditions, spatial variability in edge effects was only partially foreseeable: relatively predictable effects were caused by the differing proximity of plots to forest edge and varying matrix vegetation, but windstorms generated much random variability. Temporal variability in edge phenomena was also only partially predictable: forest dynamics varied somewhat with fragment age, but also fluctuated markedly over time, evidently because of sporadic droughts and windstorms. Given the acute sensitivity of habitat fragments to local landscape and weather dynamics, we predict that fragments within the same landscape will tend to converge in species composition, whereas those in different landscapes will diverge in composition. This 'landscape-divergence hypothesis', if generally valid, will have key implications for biodiversity-conservation strategies and for understanding the dynamics of fragmented ecosystems. | |||||
BibTeX:
@article{laurance_habitat_2007, author = {Laurance, William F. and Nascimento, Henrique E. M. and Laurance, Susan G. and Andrade, Ana and Ewers, Robert M. and Harms, Kyle E. and Luizao, Regina C. C. and Ribeiro, Jose E.}, title = {Habitat Fragmentation, Variable Edge Effects, and the Landscape-Divergence Hypothesis}, journal = {PLos ONE}, year = {2007}, volume = {2}, number = {10}, pages = {e1017}, note = {Edition: 2007/10/11}, url = {://WOS:000207456000016}, doi = {https://doi.org/10.1371/journal.pone.0001017} } |
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Laurance, W.F., Merona, J., Andrade, A., Laurance, S.G., D'Angelo, S., Lovejoy, T.E. and Vasconcelos, H.L. | Rain-forest fragmentation and the phenology of Amazonian tree communities [BibTeX] |
2003 | Journal of Tropical Ecology Vol. 19, pp. 343-347 |
article | DOI URL |
BibTeX:
@article{laurance_rain-forest_2003, author = {Laurance, W. F. and Merona, Jmrd and Andrade, A. and Laurance, S. G. and D'Angelo, S. and Lovejoy, T. E. and Vasconcelos, H. L.}, title = {Rain-forest fragmentation and the phenology of Amazonian tree communities}, journal = {Journal of Tropical Ecology}, year = {2003}, volume = {19}, pages = {343--347}, url = {://WOS:000183658600014}, doi = {https://doi.org/10.1017/s0266467403003389} } |
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Laurance, W.F., Lovejoy, T.E., Vasconcelos, H.L., Bruna, E.M., Didham, R.K., Stouffer, P.C., Gascon, C., Bierregaard, R.O., Laurance, S.G. and Sampaio, E. | Ecosystem decay of Amazonian forest fragments: A 22-year investigation | 2002 | Conservation Biology Vol. 16(3), pp. 605-618 |
article | DOI URL |
Abstract: We synthesized key findings from the Biological Dynamics of Forest Fragments Project, the world's largest and longest-running experimental study of habitat fragmentation. Although initially designed to assess the influence of fragment area on Amazonian biotas, the project has yielded insights that go far beyond the original scope of the study. Results suggest that edge effects play a key role in fragment dynamics, that the matrix has a major influence on fragment connectivity and functioning, and that many Amazonian species avoid even small (textless100-m-wide) clearings. The effects of fragmentation are highly eclectic, altering species richness and abundances, species invasions, forest dynamics, the trophic structure of communities, and a variety of ecological and ecosystem processes. Moreover, forest fragmentation appears to interact synergistically with ecological changes such as hunting, fires, and logging, collectively posing an even greater threat to the rainforest biota. | |||||
BibTeX:
@article{laurance_ecosystem_2002, author = {Laurance, W. F. and Lovejoy, T. E. and Vasconcelos, H. L. and Bruna, E. M. and Didham, R. K. and Stouffer, P. C. and Gascon, C. and Bierregaard, R. O. and Laurance, S. G. and Sampaio, E.}, title = {Ecosystem decay of Amazonian forest fragments: A 22-year investigation}, journal = {Conservation Biology}, year = {2002}, volume = {16}, number = {3}, pages = {605--618}, url = {://WOS:000175832000009}, doi = {https://doi.org/10.1046/j.1523-1739.2002.01025.x} } |
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Laurance, W.F., Laurance, S.G. and Delamonica, P. | Tropical forest fragmentation and greenhouse gas emissions | 1998 | Forest Ecology and Management Vol. 110(1-3), pp. 173-180 |
article | DOI URL |
Abstract: Rainforest fragments in central Amazonia have been found to experience a marked loss of above-ground biomass caused by sharply increased rates of tree mortality and damage near fragment margins. These findings suggest that fragmentation of tropical forests is likely to increase emissions of CO2 and other greenhouse gases above and beyond that caused by deforestation per se. We estimated committed carbon emissions from deforestation and fragmentation in Amazonia, using three simulated models of landscape change: a 'Rondonia scenario,' which mimicked settlement schemes of small farmers in the southern Amazon; a 'Para scenario,' which imitated large cattle ranches in the eastern Amazon; and a 'random scenario,' in which forest tracts were cleared randomly. Estimates of carbon emissions for specific landscapes were from 0.3 to 42% too low, depending on the amount and spatial pattern of clearing, when based solely on deforestation. Because they created irregular habitat edges or many forest perforations which increased tree mortality, the Rondonia and random-clearing scenarios produced 2-5 times more fragmentation-induced carbon emissions than did the Para scenario, for any given level of clearing. Using current estimates of forest conversion, our simulations suggest that committed carbon emissions from forest fragmentation alone will range from 3.0 to 15.6 million t/year in the Brazilian Amazon, and from 22 to 149 million t/year for tropical forests globally. (C) 1998 Elsevier Science B.V. | |||||
BibTeX:
@article{laurance_tropical_1998, author = {Laurance, W. F. and Laurance, S. G. and Delamonica, P.}, title = {Tropical forest fragmentation and greenhouse gas emissions}, journal = {Forest Ecology and Management}, year = {1998}, volume = {110}, number = {1-3}, pages = {173--180}, url = {://WOS:000076717400014}, doi = {https://doi.org/10.1016/s0378-1127(98)00291-6} } |
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Laurance, W.F., Gascon, C. and Rankin-de Merona, J.M. | Predicting effects of habitat destruction on plant communities: A test of a model using Amazonian trees | 1999 | Ecological Applications Vol. 9(2), pp. 548-554 |
article | DOI URL |
Abstract: We devised a "random-clearing model" to predict effects of habitat loss on plant communities and populations. The model yields the probability that a species will be extirpated by land clearing, based on only two parameters: its density and the percentage of the landscape that has been cleared. It can also be used to predict species richness of plant communities following clearing, so long as densities of individual species are known. We tested the model using data on the distributions of 200 tree species (greater than or equal to 10 cm dbh) within two 9-ha experimental landscapes in central Amazonia. Deforestation levels ranging from 20% to 99% of the landscape were simulated randomly, with the actual persistence of each species being the number of times it remained in the landscape after 1000 runs. The model was effective in all cases, explaining 83-99% of the total variability in species persistence on each plot. Species' distribution patterns explained some residual variation in persistence but were of negligible importance compared to the predictions of the model. We also used the model to predict species richness, simulating both random and realistically contagious patterns of deforestation. Again, the model was highly effective, explaining 96% to 98% of the total variation in richness. Surprisingly, there was little difference in richness between random and contagious clearing patterns. These results suggest that, at least at the limited spatial scale of our analysis, the effects of deforestation on plant persistence and richness can be predicted using a simple model that assumes random species distributions and deforestation patterns. The model makes four predictions: (1) Density has an overriding influence on the susceptibility of species to clearing, while distribution patterns are usually of much lesser importance. (2) The relationship between density and persistence is nonlinear. (3) Rare species (less than or equal to 1 tree/ha) become exceptionally vulnerable in heavily degraded landscapes and in small forest remnants. (4) The distinction between high (e.g., 95%) and very high (e.g., 99%) levels of habitat clearing in terms of species persistence is often dramatic. | |||||
BibTeX:
@article{laurance_predicting_1999, author = {Laurance, W. F. and Gascon, C. and Rankin-de Merona, J. M.}, title = {Predicting effects of habitat destruction on plant communities: A test of a model using Amazonian trees}, journal = {Ecological Applications}, year = {1999}, volume = {9}, number = {2}, pages = {548--554}, url = {://WOS:000081250200021}, doi = {https://doi.org/10.1890/1051-0761(1999)009%5B0548:peohdo%5D2.0.co;2} } |
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Laurance, W.F., Ferreira, L.V., Rankin-De Merona, J.M., Laurance, S.G., Hutchings, R.W. and Lovejoy, T.E. | Effects of forest fragmentation on recruitment patterns in Amazonian tree communities [BibTeX] |
1998 | Conservation Biology Vol. 12(2), pp. 460-464 |
article | DOI URL |
BibTeX:
@article{laurance_effects_1998, author = {Laurance, W. F. and Ferreira, L. V. and Rankin-De Merona, J. M. and Laurance, S. G. and Hutchings, R. W. and Lovejoy, T. E.}, title = {Effects of forest fragmentation on recruitment patterns in Amazonian tree communities}, journal = {Conservation Biology}, year = {1998}, volume = {12}, number = {2}, pages = {460--464}, url = {://WOS:000073215200025}, doi = {https://doi.org/10.1046/j.1523-1739.1998.97175.x} } |
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Laurance, W.F., Ferreira, L.V., Rankin-De Merona, J.M. and Laurance, S.G. | Rain forest fragmentation and the dynamics of Amazonian tree communities | 1998 | Ecology Vol. 79(6), pp. 2032-2040 |
article | DOI URL |
Abstract: Few studies have assessed effects of habitat fragmentation on tropical forest dynamics. We describe results from an 18-yr experimental study of the effects of rain forest fragmentation on tree-community dynamics in central Amazonia. Tree communities were assessed in 39 permanent, 1-ha plots in forest fragments of 1, 10, or 100 ha in area, and in 27 plots in nearby continuous forest. Repeated censuses of textgreater56 000 marked trees (greater than or equal to 10 cm diameter at breast height) were used to generate annualized estimates of tree mortality, damage, and turnover in fragmented and continuous forest. On average, forest fragments exhibited markedly elevated dynamics, apparently as a result of increased windthrow and microclimatic changes near forest edges. Mean mortality, damage, and turnover rates were much higher within 60 m of edges (4.01, 4.10, and 3.16%, respectively) and moderately higher within 60-100 m of edges (2.40, 1.96, and 2.05%) than in forest interiors (1.27, 1.48, and 1.15%). Less-pronounced changes in mortality and turnover rates were apparently detectable up to similar to 300 m from forest edges. Edge aspect had no significant effect on forest dynamics. Tree mortality and damage rates did not vary significantly with fragment age, suggesting that increased dynamics are not merely transitory effects that occur immediately after fragmentation, while turnover rates increased with age in most (8/9) fragments. These findings reveal that fragmentation causes important changes in the dynamics of Amazonian forests, especially within similar to 100 m of habitat edges. A mathematical "core-area model" incorporating these data predicted that edge effects will increase rapidly in importance once fragments fall below similar to 100-400 ha in area, depending on fragment shape. Accelerated dynamics in fragments will alter forest structure, floristic composition, biomass, and microclimate and are likely to exacerbate effects of fragmentation on disturbance-sensitive species. | |||||
BibTeX:
@article{laurance_rain_1998, author = {Laurance, W. F. and Ferreira, L. V. and Rankin-De Merona, J. M. and Laurance, S. G.}, title = {Rain forest fragmentation and the dynamics of Amazonian tree communities}, journal = {Ecology}, year = {1998}, volume = {79}, number = {6}, pages = {2032--2040}, url = {://WOS:000075752700015}, doi = {https://doi.org/10.1890/0012-9658(1998)079%5B2032:rffatd%5D2.0.co;2} } |
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Laurance, W.F., Ferreira, L.V., Rankin-de Merona, J.M. and Hutchings, R.W. | Influence of plot shape on estimates of tree diversity and community composition in central Amazonia [BibTeX] |
1998 | Biotropica Vol. 30(4), pp. 662-665 |
article | DOI URL |
BibTeX:
@article{laurance_influence_1998, author = {Laurance, W. F. and Ferreira, L. V. and Rankin-de Merona, J. M. and Hutchings, R. W.}, title = {Influence of plot shape on estimates of tree diversity and community composition in central Amazonia}, journal = {Biotropica}, year = {1998}, volume = {30}, number = {4}, pages = {662--665}, url = {://WOS:000078081800018}, doi = {https://doi.org/10.1111/j.1744-7429.1998.tb00106.x} } |
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Laurance, W.F., Fearnside, P.M., Laurance, S.G., Delamonica, P., Lovejoy, T.E., Rankin-de Merona, J., Chambers, J.Q. and Gascon, C. | Relationship between soils and Amazon forest biomass: A landscape-scale study | 1999 | Forest Ecology and Management Vol. 118(1-3), pp. 127-138 |
article | DOI URL |
Abstract: Above-ground dry biomass of living trees including palms was estimated in 65 l ha plots spanning a 1000 km(2) landscape in central Amazonia. The study area was located on heavily weathered, nutrient-poor soils that are widespread in the Amazon region. Biomass values were derived by measuring the diameter-at-breast-height (DBH) of all greater than or equal to 10 cm trees in each plot, then using an allometric equation and correction factor for small trees to estimate total tree biomass. Detailed information on soil texture, organic carbon, available water capacity, pH, macro- and micro-nutrients, and trace elements was collected from soil surface samples (0-20 cm) in each plot, while slope was measured with a clinometer. Biomass estimates varied more than two-fold, from 231 to 492 metric tons ha(-1), with a mean of 356 +/- 47 tons ha(-1). Simple correlations with stringent (p textless 0.006) Bonferroni corrections suggested that biomass was positively associated with total N, total exchangeable bases, K+, Mg2+, clay, and organic C in soils, and negatively associated with Zn+, aluminum saturation, and sand. An ordination analysis revealed one major and several minor soil gradients in the study area, with the main gradient discriminating sites with varying proportions of clay (with clayey soils having higher concentrations of total N, organic C, most cations, and lower aluminum saturation and less sand). A multiple regression analysis revealed that the major clay-nutrient gradient was the only significant predictor, with the model explaining 32.3% of the total variation in biomass. Results of the analysis suggest that soil-fertility parameters can account for a third or more of the variation in above-ground biomass in Amazonian terra-firme forests. We suggest that, because the conversion of forest to pasture tends to reduce the nitrogen, clay, organic carbon, and nutrient contents of soils, forests that regenerate on formerly cleared lands may have lower biomass than the original forest, especially in areas with low soil fertility. (C) 1999 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{laurance_relationship_1999, author = {Laurance, W. F. and Fearnside, P. M. and Laurance, S. G. and Delamonica, P. and Lovejoy, T. E. and Rankin-de Merona, J. and Chambers, J. Q. and Gascon, C.}, title = {Relationship between soils and Amazon forest biomass: A landscape-scale study}, journal = {Forest Ecology and Management}, year = {1999}, volume = {118}, number = {1-3}, pages = {127--138}, url = {://WOS:000079561800012}, doi = {https://doi.org/10.1016/s0378-1127(98)00494-0} } |
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Laurance, W.F., Fearnside, P.M., Cochrane, M.A., D'Angelo, S., Bergen, S. and Delamonica, P. | Development of the Brazilian Amazon - Response [BibTeX] |
2001 | Science Vol. 292(5522), pp. 1652-1654 |
article | URL |
BibTeX:
@article{laurance_development_2001, author = {Laurance, W. F. and Fearnside, P. M. and Cochrane, M. A. and D'Angelo, S. and Bergen, S. and Delamonica, P.}, title = {Development of the Brazilian Amazon - Response}, journal = {Science}, year = {2001}, volume = {292}, number = {5522}, pages = {1652--1654}, url = {://WOS:000169031800019} } |
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Laurance, W.F., Fearnside, P.M., Albernaz, A.K.M., Vasconcelos, H.L. and Ferreira, L.V. | Amazonian deforestation models - Response [BibTeX] |
2005 | Science Vol. 307(5712), pp. 1044-1044 |
article | URL |
BibTeX:
@article{laurance_amazonian_2005, author = {Laurance, W. F. and Fearnside, P. M. and Albernaz, A. K. M. and Vasconcelos, H. L. and Ferreira, L. V.}, title = {Amazonian deforestation models - Response}, journal = {Science}, year = {2005}, volume = {307}, number = {5712}, pages = {1044--1044}, url = {://WOS:000227197300021} } |
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Laurance, W.F. and Fearnside, P.M. | Amazon burning [BibTeX] |
1999 | Trends in Ecology & Evolution Vol. 14(11), pp. 457-457 |
article | DOI URL |
BibTeX:
@article{laurance_amazon_1999, author = {Laurance, W. F. and Fearnside, P. M.}, title = {Amazon burning}, journal = {Trends in Ecology & Evolution}, year = {1999}, volume = {14}, number = {11}, pages = {457--457}, note = {Edition: 1999/10/08}, url = {://WOS:000083141800016}, doi = {https://doi.org/10.1016/s0169-5347(99)01731-0} } |
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Laurance, W.F., Delamonica, P., Laurance, S.G., Vasconcelos, H.L. and Lovejoy, T.E. | Conservation - Rainforest fragmentation kills big trees [BibTeX] |
2000 | Nature Vol. 404(6780), pp. 836-836 |
article | DOI URL |
BibTeX:
@article{laurance_conservation_2000, author = {Laurance, W. F. and Delamonica, P. and Laurance, S. G. and Vasconcelos, H. L. and Lovejoy, T. E.}, title = {Conservation - Rainforest fragmentation kills big trees}, journal = {Nature}, year = {2000}, volume = {404}, number = {6780}, pages = {836--836}, note = {Edition: 2000/04/29}, url = {://WOS:000086625000034}, doi = {https://doi.org/10.1038/35009032} } |
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Laurance, W.F., Cochrane, M.A., Bergen, S., Fearnside, P.M., Delamonica, P., Barber, C., D'Angelo, S. and Fernandes, T. | Environment - The future of the Brazilian Amazon [BibTeX] |
2001 | Science Vol. 291(5503), pp. 438-439 |
article | DOI URL |
BibTeX:
@article{laurance_environment_2001, author = {Laurance, W. F. and Cochrane, M. A. and Bergen, S. and Fearnside, P. M. and Delamonica, P. and Barber, C. and D'Angelo, S. and Fernandes, T.}, title = {Environment - The future of the Brazilian Amazon}, journal = {Science}, year = {2001}, volume = {291}, number = {5503}, pages = {438--439}, note = {Edition: 2001/03/03}, url = {://WOS:000166487500023}, doi = {https://doi.org/10.1126/science.291.5503.438} } |
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Laurance, W.F. and Cochrane, M.A. | Special section: Synergistic effects in fragmented landscapes [BibTeX] |
2001 | Conservation Biology Vol. 15(6), pp. 1488-1489 |
article | DOI URL |
BibTeX:
@article{laurance_special_2001, author = {Laurance, W. F. and Cochrane, M. A.}, title = {Special section: Synergistic effects in fragmented landscapes}, journal = {Conservation Biology}, year = {2001}, volume = {15}, number = {6}, pages = {1488--1489}, url = {://WOS:000172692900007}, doi = {https://doi.org/10.1046/j.1523-1739.2001.01088.x} } |
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Laurance, W.F., Albernaz, A.K.M., Schroth, G., Fearnside, P.M., Bergen, S., Venticinque, E.M. and Da Costa, C. | Predictors of deforestation in the Brazilian Amazon | 2002 | Journal of Biogeography Vol. 29(5-6), pp. 737-748 |
article | DOI URL |
Abstract: Aim and Location We assessed the effects of biophysical and anthropogenic predictors on deforestation in Brazilian Amazonia. This region has the world's highest absolute rates of forest destruction and fragmentation. Methods Using a GIS, spatial data coverages were developed for deforestation and for three types of potential predictors: (1) human-demographic factors (rural-population density, urban-population size); (2) factors that affect physical accessibility to forests (linear distances to the nearest paved highway, unpaved road and navigable river), and (3) factors that may affect land-use suitability for human occupation and agriculture (annual rainfall, dry-season severity, soil fertility, soil waterlogging, soil depth). To reduce the effects of spatial autocorrelation among variables, the basin was subdivided into textgreater1900 quadrats of 50 x 50 km, and a random subset of 120 quadrats was selected that was stratified on deforestation intensity. A robust ordination analysis (non-metric multidimensional scaling) was then used to identify key orthogonal gradients among the ten original predictor variables. Results The ordination revealed two major environmental gradients in the study area. Axis 1 discriminated among areas with relatively dense human populations and highways, and areas with sparse populations and no highways; whereas axis 2 described a gradient between wet sites having low dry-season severity, many navigable rivers and few roads, and those with opposite values. A multiple regression analysis revealed that both factors were highly significant predictors, collectively explaining nearly 60% of the total variation in deforestation intensity (F (2,117) = 85.46, P textless 0.0001). Simple correlations of the original variables were highly concordant with the multiple regression model and suggested that highway density and rural-population size were the most important correlates of deforestation. Main conclusins These trends suggest that deforestation in the Brazilian Amazon is being largely determined by three proximate factors: human population density, highways and dry-season severity, all of which increase deforestation. At least at the spatial scale of this analysis, soil fertility and waterlogging had little influence on deforestation activity, and soil depth was only marginally significant. Our findings suggest that current policy initiatives designed to increase immigration and dramatically expand highway and infrastructure networks in the Brazilian Amazon are likely to have important impacts on deforestation activity. Deforestation will be greatest in relatively seasonal, south-easterly areas of the basin, which are most accessible to major population centres and where large-scale cattle ranching and slash-and-burn farming are most easily implemented. | |||||
BibTeX:
@article{laurance_predictors_2002, author = {Laurance, W. F. and Albernaz, A. K. M. and Schroth, G. and Fearnside, P. M. and Bergen, S. and Venticinque, E. M. and Da Costa, C.}, title = {Predictors of deforestation in the Brazilian Amazon}, journal = {Journal of Biogeography}, year = {2002}, volume = {29}, number = {5-6}, pages = {737--748}, url = {://WOS:000176652300016}, doi = {https://doi.org/10.1046/j.1365-2699.2002.00721.x} } |
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Laurance, W.F., Albernaz, A.K.M., Fearnside, P.M., Vasconcelos, H.L. and Ferreira, L.V. | Underlying causes of deforestation - Response [BibTeX] |
2005 | Science Vol. 307(5712), pp. 1046-1047 |
article | URL |
BibTeX:
@article{laurance_underlying_2005, author = {Laurance, W. F. and Albernaz, A. K. M. and Fearnside, P. M. and Vasconcelos, H. L. and Ferreira, L. V.}, title = {Underlying causes of deforestation - Response}, journal = {Science}, year = {2005}, volume = {307}, number = {5712}, pages = {1046--1047}, url = {://WOS:000227197300025} } |
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Laurance, W.F., Albernaz, A.K.M., Fearnside, P.M., Vasconcelos, H.L. and Ferreira, L.V. | Deforestation in Amazonia [BibTeX] |
2004 | Science Vol. 304(5674), pp. 1109-1109 |
article | DOI URL |
BibTeX:
@article{laurance_deforestation_2004, author = {Laurance, W. F. and Albernaz, A. K. M. and Fearnside, P. M. and Vasconcelos, H. L. and Ferreira, L. V.}, title = {Deforestation in Amazonia}, journal = {Science}, year = {2004}, volume = {304}, number = {5674}, pages = {1109--1109}, note = {Edition: 2004/05/25}, url = {://WOS:000221524500018}, doi = {https://doi.org/10.1126/science.304.5674.1109b} } |
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Laurance, W.F., Albernaz, A.K.M. and Da Costa, C. | Is deforestation accelerating in the Brazilian Amazon? | 2001 | Environmental Conservation Vol. 28(4), pp. 305-311 |
article | DOI URL |
Abstract: Recent studies suggest that deforestation rates in the Brazilian Amazon could increase sharply in the future as a result of over US$ 40 billion in planned investments in highway paving and major new infrastructure projects in the region. These studies have been challenged by several Brazilian ministries, which assert that recent improvements in environmental laws, enforcement and public attitudes have fundamentally reduced the threat posed to forests by such projects. The notion that hazards to Amazonian forests have declined over the last decade was assessed using available data on deforestation rates from 1978 to 2000. Although the alarmingly high rate of forest loss during 1978-1989 (1.98 million ha yr(-1)) declined somewhat in 1990-1994 (1.38 million ha yr(-1)), it rebounded to a high level in the period 1995-2000 (1.90 million ha yr(-1)). Moreover, correlation and regression analyses reveal that both absolute and per caput rates of forest loss accelerated significantly over the last decade. These trends fail to support the assertion that deforestation pressure in Amazonian forests has been brought under control. Poor enforcement of existing environmental laws, rapidly expanding logging and mining industries, increasing population pressure and other challenges are greatly hindering efforts to limit the environmental impacts of development activities in Brazilian Amazonia. | |||||
BibTeX:
@article{laurance_is_2001, author = {Laurance, W. F. and Albernaz, A. K. M. and Da Costa, C.}, title = {Is deforestation accelerating in the Brazilian Amazon?}, journal = {Environmental Conservation}, year = {2001}, volume = {28}, number = {4}, pages = {305--311}, url = {://WOS:000174843100003}, doi = {https://doi.org/10.1017/s0376892901000339} } |
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Laurance, W.F. | A new initiative to use carbon trading for tropical forest conservation | 2007 | Biotropica Vol. 39(1), pp. 20-24 |
article | DOI URL |
Abstract: I describe a new initiative, led by a coalition of developing nations, to devise a viable mechanism for using carbon trading to protect old-growth tropical forests. I highlight some of the practical and political hurdles involved in forest-carbon trading, and explain why this initiative is rapidly gaining broad-based political support. | |||||
BibTeX:
@article{laurance_new_2007, author = {Laurance, William F.}, title = {A new initiative to use carbon trading for tropical forest conservation}, journal = {Biotropica}, year = {2007}, volume = {39}, number = {1}, pages = {20--24}, url = {://WOS:000243294500002}, doi = {https://doi.org/10.1111/j.1744-7429.2006.00229.x} } |
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Laurance, W.F. | Switch to corn promotes Amazon deforestation [BibTeX] |
2007 | Science Vol. 318(5857), pp. 1721-1721 |
article | DOI URL |
BibTeX:
@article{laurance_switch_2007, author = {Laurance, William F.}, title = {Switch to corn promotes Amazon deforestation}, journal = {Science}, year = {2007}, volume = {318}, number = {5857}, pages = {1721--1721}, note = {Edition: 2007/12/15}, url = {://WOS:000251616800013}, doi = {https://doi.org/10.1126/science.318.5857.1721b} } |
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Laurance, W.F. | When bigger is better: the need for Amazonian mega-reserves | 2005 | Trends in Ecology & Evolution Vol. 20(12), pp. 645-648 |
article | DOI URL |
Abstract: The rate of forest destruction has accelerated sharply in Brazilian Amazonia, but there are also vital conservation opportunities with the ongoing designation of important new protected areas. In a timely paper, Carlos Peres argues that an extensive network of mega-reserves, operationally defined as those exceeding 1 million ha in area, is needed to ensure the long-term persistence of Amazonian species and ecological processes. Although such protected areas might seem excessively large to some, disparate lines of evidence suggest that mega-reserves are vital for the future of Amazonian biodiversity. | |||||
BibTeX:
@article{laurance_when_2005, author = {Laurance, W. F.}, title = {When bigger is better: the need for Amazonian mega-reserves}, journal = {Trends in Ecology & Evolution}, year = {2005}, volume = {20}, number = {12}, pages = {645--648}, note = {Edition: 2006/05/17}, url = {://WOS:000233878700002}, doi = {https://doi.org/10.1016/j.tree.2005.10.009} } |
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Laurance, W.F. | Forest-climate interactions in fragmented tropical landscapes | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 345-352 |
article | DOI URL |
Abstract: In the tropics, habitat fragmentation alters forest-climate interactions in diverse ways. On a local scale (less than I km), elevated desiccation and wind disturbance near fragment margins lead to sharply increased tree mortality, thus altering canopy-gap dynamics, plant community composition, biomass dynamics and carbon storage. Fragmented forests are also highly vulnerable to edge-related fires, especially in regions with periodic droughts or strong dry seasons. At landscape to regional scales (10-1000 km), habitat fragmentation may have complex effects on forest-climate interactions, with important consequences for atmospheric circulation, water cycling and precipitation. Positive feedbacks among deforestation, regional climate change and fire could pose a serious threat for some tropical forests, but the details of such interactions are poorly understood. | |||||
BibTeX:
@article{laurance_forest-climate_2004, author = {Laurance, W. F.}, title = {Forest-climate interactions in fragmented tropical landscapes}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {345--352}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100004}, doi = {https://doi.org/10.1098/rstb.2003.1430} } |
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Laurance, W.F. | Slow burn: the insidious effects of surface fires on tropical forests | 2003 | Trends in Ecology & Evolution Vol. 18(5), pp. 209-212 |
article | DOI URL |
Abstract: Accidental surface fires are emerging as one of the most pervasive threats to tropical forests. Although unimpressive in appearance, these fires can have surprisingly potent impacts on rainforest plant and animal communities, as demonstrated by recent studies led by Jos Barlow and Carlos Peres in central Amazonia. Even worse, surface fires greatly increase the likelihood of far larger conflagrations that can lead to complete forest destruction. | |||||
BibTeX:
@article{laurance_slow_2003, author = {Laurance, W. F.}, title = {Slow burn: the insidious effects of surface fires on tropical forests}, journal = {Trends in Ecology & Evolution}, year = {2003}, volume = {18}, number = {5}, pages = {209--212}, url = {://WOS:000183117100002}, doi = {https://doi.org/10.1016/s0169-5347(03)00064-8} } |
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Laurance, W.F. | Tropical logging and human invasions [BibTeX] |
2001 | Conservation Biology Vol. 15(1), pp. 4-5 |
article | DOI URL |
BibTeX:
@article{laurance_tropical_2001, author = {Laurance, W. F.}, title = {Tropical logging and human invasions}, journal = {Conservation Biology}, year = {2001}, volume = {15}, number = {1}, pages = {4--5}, url = {://WOS:000167170400003}, doi = {https://doi.org/10.1046/j.1523-1739.2001.00_11-2.x} } |
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Laurance, W.F. | The future of the Brazilian Amazon [BibTeX] |
2001 | Science Vol. 291(5506), pp. 988-988 |
article | URL |
BibTeX:
@article{laurance_future_2001, author = {Laurance, W. F.}, title = {The future of the Brazilian Amazon}, journal = {Science}, year = {2001}, volume = {291}, number = {5506}, pages = {988--988}, url = {://WOS:000166860100024} } |
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Laurance, W.F. | Cut and run: the dramatic rise of transnational logging in the tropics [BibTeX] |
2000 | Trends in Ecology & Evolution Vol. 15(11), pp. 433-434 |
article | DOI URL |
BibTeX:
@article{laurance_cut_2000, author = {Laurance, W. F.}, title = {Cut and run: the dramatic rise of transnational logging in the tropics}, journal = {Trends in Ecology & Evolution}, year = {2000}, volume = {15}, number = {11}, pages = {433--434}, note = {Edition: 2000/10/26}, url = {://WOS:000165122400001}, doi = {https://doi.org/10.1016/s0169-5347(00)01962-5} } |
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Laurance, W.F. | Mega-development trends in the Amazon: Implications for global change | 2000 | Environmental Monitoring and Assessment Vol. 61(1), pp. 113-122 |
article | DOI URL |
Abstract: This paper describes four global-change phenomena that are having major impacts on Amazonian forests. The first is accelerating deforestation and logging. Despite recent government initiatives to slow forest loss, deforestation rates in Brazilian Amazonia have increased from 1.1 million ha yr(-1) in the early 1990s, to nearly 1.5 million ha yr(-1) from 1992-1994, and to more than 1.9 million ha yr(-1) from 1995-1998. Deforestation is also occurring rapidly in some other parts of the Amazon Basin, such as in Bolivia and Ecuador, while industrialized logging is increasing dramatically in the Guianas and central Amazonia. The second phenomenon is that patterns of forest loss and fragmentation are rapidly changing. In recent decades, large-scale deforestation has mainly occurred in the southern and eastern portions of the Amazon - in the Brazilian states of Para, Maranhao, Rondonia, Acre, and Mate Grosso, and in northern Bolivia. While rates of forest loss remain very high in these areas, the development of major new highways is providing direct conduits into the heart of the Amazon. If future trends follow past patterns, land-hungry settlers and loggers may largely bisect the forests of the Amazon Basin. The third phenomenon is that climatic variability is interacting with human land uses, creating additional impacts on forest ecosystems. The 1997/98 Fl Nino drought, for example, led to a major increase in forest burning, with wildfires raging out of control in the northern Amazonian state of Roraima and other locations. Logging operations, which create labyrinths of roads and tracks in forests, are increasing fuel loads, desiccation and ignition sources in forest interiors. Forest fragmentation also increases fire susceptibility by creating dry, fire-prone forest edges. Finally, recent evidence suggests that intact Amazonian forests are a globally significant carbon sink, quite possibly caused by higher forest growth rates in response to increasing atmospheric CO2 fertilization. Evidence for a carbon sink comes from long-term forest mensuration plots, from whole-forest studies of carbon flux and from investigations of atmospheric CO2 and oxygen isotopes. Unfortunately, intact Amazonian forests are rapidly diminishing. Hence, not only is the destruction of these forests a major source of greenhouse gases, but it is reducing their intrinsic capacity to help buffer the rapid anthropogenic rise in CO2. | |||||
BibTeX:
@article{laurance_mega-development_2000, author = {Laurance, W. F.}, title = {Mega-development trends in the Amazon: Implications for global change}, journal = {Environmental Monitoring and Assessment}, year = {2000}, volume = {61}, number = {1}, pages = {113--122}, url = {://WOS:000086270100009}, doi = {https://doi.org/10.1023/a:1006374320085} } |
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Laurance, W.F. | Do edge effects occur over large spatial scales? [BibTeX] |
2000 | Trends in Ecology & Evolution Vol. 15(4), pp. 134-135 |
article | DOI URL |
BibTeX:
@article{laurance_edge_2000, author = {Laurance, W. F.}, title = {Do edge effects occur over large spatial scales?}, journal = {Trends in Ecology & Evolution}, year = {2000}, volume = {15}, number = {4}, pages = {134--135}, url = {://WOS:000086146200005}, doi = {https://doi.org/10.1016/s0169-5347(00)01838-3} } |
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Laurance, W.F. | Reflections on the tropical deforestation crisis | 1999 | Biological Conservation Vol. 91(2-3), pp. 109-117 |
article | DOI URL |
Abstract: Tropical forests do far more than sustain biodiversity; they are homes to indigenous peoples, pharmacopeias of natural products, and provide vital ecosystem services, such as flood amelioration and soil conservation. At regional and global scales, tropical forests also have a major influence on carbon storage and climate. I highlight these benefits, then assess the pattern and pace of tropical forest destruction in the Americas, Asia, and Africa. Asia emerges as the most immediate concern, because it has less surviving forest than the other two regions and higher relative rates of deforestation and logging. At regional and national levels, however, there is enormous variation in rates of forest loss. I discuss some factors that tend to promote forest conversion in developing countries, and propose that four - human population pressure. weak government institutions and poor policies, increasing trade liberalization, and industrial logging - are emerging as key drivers of forest destruction. (C) 1999 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{laurance_reflections_1999, author = {Laurance, W. F.}, title = {Reflections on the tropical deforestation crisis}, journal = {Biological Conservation}, year = {1999}, volume = {91}, number = {2-3}, pages = {109--117}, url = {://WOS:000083531100003}, doi = {https://doi.org/10.1016/s0006-3207(99)00088-9} } |
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Laurance, W.F. | Ecology and management of fragmented tropical landscapes - Introduction and synthesis [BibTeX] |
1999 | Biological Conservation Vol. 91(2-3), pp. 101-107 |
article | DOI URL |
BibTeX:
@article{laurance_ecology_1999, author = {Laurance, W. F.}, title = {Ecology and management of fragmented tropical landscapes - Introduction and synthesis}, journal = {Biological Conservation}, year = {1999}, volume = {91}, number = {2-3}, pages = {101--107}, url = {://WOS:000083531100002}, doi = {https://doi.org/10.1016/s0006-3207(99)00087-7} } |
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Laurance, W.F. | A crisis in the making: responses of Amazonian forests to land use and climate change | 1998 | Trends in Ecology & Evolution Vol. 13(10), pp. 411-415 |
article | DOI URL |
Abstract: At least three global-change phenomena are having major impacts on Amazonian forests: (1) accelerating deforestation and logging; (2) rapidly changing patterns of forest loss; and (3) interactions between human land-use and climatic variability. Additional alterations caused by climatic change, rising concentrations of atmospheric carbon dioxide, mining, overhunting and other large-scale phenomena could also have important effects on the Amazon ecosystem. Consequently, decisions regarding Amazon forest use in the next decade are crucial to its future existence. | |||||
BibTeX:
@article{laurance_crisis_1998, author = {Laurance, W. F.}, title = {A crisis in the making: responses of Amazonian forests to land use and climate change}, journal = {Trends in Ecology & Evolution}, year = {1998}, volume = {13}, number = {10}, pages = {411--415}, url = {://WOS:000075997500018}, doi = {https://doi.org/10.1016/s0169-5347(98)01433-5} } |
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Lathuillière, M.J., Dalmagro, H.J., Black, T.A., Arruda, P.H.d., Hawthorne, I., Couto, E.G. and Johnson, M. | Rain-fed and irrigated cropland-atmosphere water fluxes and their implications for agricultural production in Southern Amazonia [BibTeX] |
2018 | Agricultural and Forest Meteorology Vol. 256–257, pp. 407-419 |
article | DOI |
BibTeX:
@article{lathuilliere_rain-fed_2018, author = {Lathuillière, M. J. and Dalmagro, Hi. J. and Black, T. Andrew and Arruda, Paulo H.Z. de and Hawthorne, I. and Couto, E. G. and Johnson, M.S.}, title = {Rain-fed and irrigated cropland-atmosphere water fluxes and their implications for agricultural production in Southern Amazonia}, journal = {Agricultural and Forest Meteorology}, year = {2018}, volume = {256–257}, pages = {407--419}, doi = {https://doi.org/10.1016/j.agrformet.2018.03.023} } |
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Nagy, L., Forsberg, B.R. and Artaxo, P. | Interactions Between Biosphere, Atmosphere, and Human Land Use in the Amazon Basin: An Introduction [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 3-15 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_interactions_2016, author = {Laszlo Nagy, Bruce R. Forsberg, Paulo Artaxo}, title = {Interactions Between Biosphere, Atmosphere, and Human Land Use in the Amazon Basin: An Introduction}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {3--15}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Lapola, D., Schaldach, R. and Alcamo, J. | Impacts of Climate Change and the End of Deforestation on Land Use in the Brazilian Legal Amazon | 2011 | Earth Interactions Vol. 15(16), pp. 1-29 |
article | DOI URL |
Abstract: Climate change scenarios vary considerably over the Amazon region, with an extreme scenario projecting a dangerous (from the human perspective) increase of 3.8 degrees C in temperature and 30% reduction in precipitation by 2050. The impacts of such climate change on Amazonian land-use dynamics, agricultural production, and deforestation rates are still to be determined. In this study, the authors make a first attempt to assess these impacts through a systemic approach, using a spatially explicit modeling framework to project crop yield and land-use/land-cover changes in the Brazilian Amazon by 2050. The results show that, without any adaptation, climate change may exert a critical impact on the yields of crops commonly cultivated in the Amazon (e. g., soybean yields are reduced by 44% in the worst-case scenario). Therefore, following baseline projections on crop and livestock production, a scenario of severe regional climate change would cause additional deforestation of 181 000 km(2) (+20%) in the Amazon and 240 000 km(2) (+273%) in the Cerrado compared to a scenario of moderate climate change. Putting an end to deforestation in the Brazilian Amazon forest by 2020 (and of the Cerrado by 2025) would require either a reduction of 26%-40% in livestock production until 2050 or a doubling of average livestock density from 0.74 to 1.46 head per hectare. These results suggest that (i) climate change can affect land use in ways not previously explored, such as the reduction of yields entailing further deforestation, and (ii) there is a need for an integrated/multidisciplinary plan for adaptation to climate change in the Amazon. | |||||
BibTeX:
@article{lapola_impacts_2011, author = {Lapola, D.M. and Schaldach, R. and Alcamo, J.}, title = {Impacts of Climate Change and the End of Deforestation on Land Use in the Brazilian Legal Amazon}, journal = {Earth Interactions}, year = {2011}, volume = {15}, number = {16}, pages = {1--29}, url = {://000291148900001}, doi = {https://doi.org/10.1175/2010EI333.1} } |
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Lapola, D.M., Pinho, P., Barlow, J., Aragão, L.E.O.C., Berenguer, E., Carmenta, R., Liddy, H.M., Seixas, H., Silva, C.V.J., Silva-Junior, C.H.L., Alencar, A.A.C., Anderson, L.O., Armenteras, D., Brovkin, V., Calders, K., Chambers, J., Chini, L., Costa, M.H., Faria, B.L., Fearnside, P.M., Ferreira, J., Gatti, L., Gutierrez-Velez, V.H., Han, Z., Hibbard, K., Koven, C., Lawrence, P., Pongratz, J., Portela, B.T.T., Rounsevell, M., Ruane, A.C., Schaldach, R., da Silva, S.S., von Randow, C. and Walker, W.S. | The drivers and impacts of Amazon forest degradation | 2023 | Science Vol. 379(6630), pp. eabp8622 |
article | DOI URL |
Abstract: Approximately 2.5 × 106 square kilometers of the Amazon forest are currently degraded by fire, edge effects, timber extraction, and/or extreme drought, representing 38% of all remaining forests in the region. Carbon emissions from this degradation total up to 0.2 petagrams of carbon per year (Pg C year−1), which is equivalent to, if not greater than, the emissions from Amazon deforestation (0.06 to 0.21 Pg C year−1). Amazon forest degradation can reduce dry-season evapotranspiration by up to 34% and cause as much biodiversity loss as deforestation in human-modified landscapes, generating uneven socioeconomic burdens, mainly to forest dwellers. Projections indicate that degradation will remain a dominant source of carbon emissions independent of deforestation rates. Policies to tackle degradation should be integrated with efforts to curb deforestation and complemented with innovative measures addressing the disturbances that degrade the Amazon forest. The Amazon rainforest is a biodiversity hotspot under threat from ongoing land conversion and climate change. Two Analytical Reviews in this issue synthesize data on forest loss and degradation in the Amazon basin, providing a clearer picture of its current status and future prospects. Albert et al. reviewed the drivers of change in the Amazon and show that anthropogenic changes are occurring much faster than naturally occurring environmental changes of the past. Although deforestation has been widely documented in the Amazon, degradation is also having major impacts on biodiversity and carbon storage. Lapola et al. synthesized the drivers and outcomes of Amazon forest degradation from timber extraction and habitat fragmentation, fires, and drought. —BEL Two Reviews spotlight the threats of ongoing deforestation and degradation in the Amazon. | |||||
BibTeX:
@article{lapola_drivers_2023, author = {Lapola, David M. and Pinho, Patricia and Barlow, Jos and Aragão, Luiz E. O. C. and Berenguer, Erika and Carmenta, Rachel and Liddy, Hannah M. and Seixas, Hugo and Silva, Camila V. J. and Silva-Junior, Celso H. L. and Alencar, Ane A. C. and Anderson, Liana O. and Armenteras, Dolors and Brovkin, Victor and Calders, Kim and Chambers, Jeffrey and Chini, Louise and Costa, Marcos H. and Faria, Bruno L. and Fearnside, Philip M. and Ferreira, Joice and Gatti, Luciana and Gutierrez-Velez, Victor Hugo and Han, Zhangang and Hibbard, Kathleen and Koven, Charles and Lawrence, Peter and Pongratz, Julia and Portela, Bruno T. T. and Rounsevell, Mark and Ruane, Alex C. and Schaldach, Rüdiger and da Silva, Sonaira S. and von Randow, Celso and Walker, Wayne S.}, title = {The drivers and impacts of Amazon forest degradation}, journal = {Science}, year = {2023}, volume = {379}, number = {6630}, pages = {eabp8622}, url = {https://www.science.org/doi/abs/10.1126/science.abp8622}, doi = {https://doi.org/10.1126/science.abp8622} } |
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Lapola, D.M., Oyama, M.D. and Nobre, C.A. | Exploring the range of climate biome projections for tropical South America: The role of CO(2) fertilization and seasonality | 2009 | Global Biogeochemical Cycles Vol. 23(3) |
article | DOI URL |
Abstract: Tropical South America vegetation cover projections for the end of the century differ considerably depending on climate scenario and also on how physiological processes are considered in vegetation models. In this paper we use a potential vegetation model (CPTEC-PVM2) to analyze biome distribution in tropical South America under a range of climate projections and a range of estimates about the effects of increased atmospheric CO(2). We show that if the CO(2) "fertilization effect'' indeed takes place and is maintained in the long term in tropical forests, then it will avoid biome shifts in Amazonia in most of the climate scenarios, even if the effect of CO(2) fertilization is halved. However, if CO(2) fertilization does not play any important role on tropical forests in the future or if dry season is longer than 4 months (projected by 2/14 GCMs), then there is replacement of large portions of Amazonia by tropical savanna. | |||||
BibTeX:
@article{lapola_exploring_2009, author = {Lapola, David M. and Oyama, Marcos D. and Nobre, Carlos A.}, title = {Exploring the range of climate biome projections for tropical South America: The role of CO(2) fertilization and seasonality}, journal = {Global Biogeochemical Cycles}, year = {2009}, volume = {23}, number = {3}, url = {://WOS:000267642100001}, doi = {https://doi.org/10.1029/2008gb003357} } |
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Lapola, D.M. | Bytes and boots to understand the future of the Amazon forest [BibTeX] |
2018 | New Phytologist Vol. 219, pp. 845-847 |
article | |
BibTeX:
@article{lapola_bytes_2018, author = {Lapola, David M.}, title = {Bytes and boots to understand the future of the Amazon forest}, journal = {New Phytologist}, year = {2018}, volume = {219}, pages = {845--847} } |
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Langford, B., House, E., Valach, A., Hewitt, C.N., Artaxo, P., Barkley, M., Brito, J., Carnell, E., Davison, B., Mackenzie, A., Marais, E., Newland, M., Rickard, A., Shaw, M., Yañez-Serrano, A. and Nemitz, E. | Seasonality of isoprene emissions and oxidation products above the remote Amazon [BibTeX] |
1 | Environmental Science: Atmospheres | article | DOI |
BibTeX:
@article{langford_seasonality_1, author = {Langford, Ben and House, Emily and Valach, Alex and Hewitt, C. Nicholas and Artaxo, Paulo and Barkley, Michael and Brito, Joel and Carnell, Edward and Davison, Brian and Mackenzie, A. and Marais, Eloise and Newland, Mike and Rickard, Andrew and Shaw, Marvin and Yañez-Serrano, Ana and Nemitz, Eiko}, title = {Seasonality of isoprene emissions and oxidation products above the remote Amazon}, journal = {Environmental Science: Atmospheres}, year = {1}, doi = {https://doi.org/10.1039/D1EA00057H} } |
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Lang, S., Tao, W.K., Cifelli, R., Olson, W., Halverson, J., Rutledge, S. and Simpson, J. | Improving simulations of convective systems from TRMM LBA: Easterly and westerly regimes | 2007 | Journal of the Atmospheric Sciences Vol. 64(4), pp. 1141-1164 |
article | DOI URL |
Abstract: The 3D Goddard Cumulus Ensemble model is used to simulate two convective events observed during the Tropical Rainfall Measuring Mission Large-Scale Biosphere-Atmosphere (TRMM LBA) experiment in Brazil. These two events epitomized the type of convective systems that formed in two distinctly different environments observed during TRMM LBA. The 26 January 1999 squall line formed within a sheared low-level easterly wind flow. On 23 February 1999, convection developed in weak low-level westerly flow, resulting in weakly organized, less intense convection. Initial simulations captured the basic organization and intensity of each event. However, improvements to the model resolution and microphysics produced better simulations as compared to observations. More realistic diurnal convective growth was achieved by lowering the horizontal grid spacing from 1000 to 250 m. This produced a gradual transition from shallow to deep convection that occurred over a span of hours as opposed to an abrupt appearance of deep convection. Eliminating the dry growth of graupel in the bulk microphysics scheme effectively removed the unrealistic presence of high-density ice in the simulated anvil. However, comparisons with radar reflectivity data using contoured-frequency- with-altitude diagrams (CFADs) revealed that the resulting snow contents were too large. The excessive snow was reduced primarily by lowering the collection efficiency of cloud water by snow and resulted in further agreement with the radar observations. The transfer of cloud-sized particles to precipitation-sized ice appears to be too efficient in the original scheme. Overall, these changes to the microphysics lead to more realistic precipitation ice contents in the model. However, artifacts due to the inability of the one-moment scheme to allow for size sorting, such as excessive low-level rain evaporation, were also found but could not be resolved without moving to a two-moment or bin scheme. As a result, model rainfall histograms underestimated the occurrence of high rain rates compared to radar-based histograms. Nevertheless, the improved precipitation-sized ice signature in the model simulations should lead to better latent heating retrievals as a result of both better convective-stratiform separation within the model as well as more physically realistic hydrometeor structures for radiance calculations. | |||||
BibTeX:
@article{lang_improving_2007, author = {Lang, S. and Tao, W. K. and Cifelli, R. and Olson, W. and Halverson, J. and Rutledge, S. and Simpson, J.}, title = {Improving simulations of convective systems from TRMM LBA: Easterly and westerly regimes}, journal = {Journal of the Atmospheric Sciences}, year = {2007}, volume = {64}, number = {4}, pages = {1141--1164}, url = {://WOS:000245742600007}, doi = {https://doi.org/10.1175/jas3879.1} } |
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Lai, C.-T., Ometto, J.P.H.B., Berry, J.A., Martinelli, L.A., Domingues, T.F. and Ehleringer, J.R. | Life form-specific variations in leaf water oxygen-18 enrichment in Amazonian vegetation | 2008 | Oecologia Vol. 157(2), pp. 197-210 |
article | DOI URL |
Abstract: Leaf water (18)O enrichment (Delta(o)) influences the isotopic composition of both gas exchange and organic matter, with Delta(o) values responding to changes in atmospheric parameters. In order to examine possible influences of plant parameters on Do dynamics, we measured oxygen isotope ratios (delta (18)O) of leaf and stem water on plant species representing different life forms in Amazonia forest and pasture ecosystems. We conducted two field experiments: one in March ( wet season) and another in September (dry season) 2004. In each experiment, leaf and stem samples were collected at 2-h intervals at night and hourly during the day for 50 h from eight species including upper-canopy forest trees, upper-canopy forest lianas, and lower-canopy forest trees, a C(4) pasture grass and a C(3) pasture shrub. Significant life form-related differences were detected in (18)O leaf water values. Initial modeling efforts to explain these observations over-predicted nighttime Delta(o) values by as much as 10%. Across all species, errors associated with measured values of the delta (18)O of atmospheric water vapor (delta(v)) appeared to be largely responsible for the over-predictions of nighttime Delta(o) observations. We could not eliminate collection or storage of water vapor samples as a possible error and therefore developed an alternative, plant-based method for estimating the daily average delta(v) value in the absence of direct (reliable) measurements. This approach differs from the common assumption that isotopic equilibrium exists between water vapor and precipitation water, by including transpiration-based contributions from local vegetation through (18)O measurements of bulk leaf water. Inclusion of both modified delta(v) and non-steady state features resulted in model predictions that more reliably predicted both the magnitude and temporal patterns observed in the data. The influence of life form-specific patterns of Delta(o) was incorporated through changes in the effective path length, an important but little known parameter associated with the Peclet effect. | |||||
BibTeX:
@article{lai_life_2008, author = {Lai, Chun-Ta and Ometto, Jean P. H. B. and Berry, Joseph A. and Martinelli, Luiz A. and Domingues, Tomas F. and Ehleringer, James R.}, title = {Life form-specific variations in leaf water oxygen-18 enrichment in Amazonian vegetation}, journal = {Oecologia}, year = {2008}, volume = {157}, number = {2}, pages = {197--210}, note = {Edition: 2008/06/11}, url = {://WOS:000257956000002}, doi = {https://doi.org/10.1007/s00442-008-1071-5} } |
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Lahsen, M. and Nobre, C.A. | Challenges of connecting international science and local level sustainability efforts: the case of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia | 2007 | Environmental Science & Policy Vol. 10(1), pp. 62-74 |
article | DOI URL |
Abstract: The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multi-year Brazil-led international environmental science experiment funded by the U.S. National Aeronautics Space Administration, the European Union and Brazil. It is intended to inform decision making under the United Nations Framework Convention on Climate Change (UNFCCC) as well as Brazilian national environmental decision-making related to the Amazon region. Focused on the Amazon region, and primarily on the Brazilian Amazon, the LBA is a case study in issues that can arise when doing globally oriented research in a less developed country setting and a test of assumptions that such research simultaneously benefits global and local levels. This article offers a qualitative evaluation of the extent to which the LBA has achieved its goals and identifies structural obstacles within science that must be overcome to improve the fit between international science programs and efforts to nurture more sustainable use of natural resources in a less developed country. (C) 2006 Published by Elsevier Ltd. | |||||
BibTeX:
@article{lahsen_challenges_2007, author = {Lahsen, Myanna and Nobre, Carlos A.}, title = {Challenges of connecting international science and local level sustainability efforts: the case of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia}, journal = {Environmental Science & Policy}, year = {2007}, volume = {10}, number = {1}, pages = {62--74}, url = {://WOS:000243981000006}, doi = {https://doi.org/10.1016/j.envsci.2006.10.005} } |
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Lages, S., Dourado, S., Cetauro, A., Ferreira S.J. F., S.M.d.A. and Miranda | Metais Pesados como Marcadores Ambientais a Partir do Teste de T para Águas Naturais e sob Influência Antrópica no Município de Manaus – AM [BibTeX] |
2022 | Vol. 1(1)Meio ambiente: princípios ambientais, preservação e sustentabilidade 3, pp. 196-203 |
incollection | DOI |
BibTeX:
@incollection{atena_metais_2022, author = {Lages, S.A.F.; Dourado, S; Cetauro, A; Ferreira, S.J. F., Silva, M.L. da., A.S; Miranda}, title = {Metais Pesados como Marcadores Ambientais a Partir do Teste de T para Águas Naturais e sob Influência Antrópica no Município de Manaus – AM}, booktitle = {Meio ambiente: princípios ambientais, preservação e sustentabilidade 3}, publisher = {Organizadores Danyelle Andrade Mota, Clécio Danilo Dias da Silva, Lays Carvalho de Almeida, et al.}, year = {2022}, volume = {1}, number = {1}, pages = {196--203}, doi = {https://doi.org/10.22533/at.ed.318222903} } |
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Lages, S., Dourado, S., Oliveria, D., Cetauro, A., Nascimento, W., Miranda S.A.F., A. and Bringel | Testes de Significância aplicados ao Estudo da Demanda Bioquímica de Oxigênio. [BibTeX] |
2021 | Scientia Amazonia Vol. 10(2), pp. C1-C9 |
article | |
BibTeX:
@article{lages_testes_2021, author = {Lages, S.B.; Dourado, S; Oliveria, D; Cetauro, A; Nascimento, W.J; Miranda, S.A.F., A.S; Bringel}, title = {Testes de Significância aplicados ao Estudo da Demanda Bioquímica de Oxigênio.}, journal = {Scientia Amazonia}, year = {2021}, volume = {10}, number = {2}, pages = {C1--C9} } |
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Lages, A., Miranda, S., Dourado, S., Oliveria, D., Cetauro, A., Bringel, S., Ferreira, S. and Silva, M. | Quimiometria aplicada a avaliação química do Igarapé que cruza o polo industrial de Manaus-AM [BibTeX] |
2021 | Revista Ibero-Americana de Ciências Ambientais Vol. 12(10) |
article | |
BibTeX:
@article{lages_quimiometria_2021, author = {Lages, A.S. and Miranda, S.A.F. and Dourado, S. and Oliveria, D; and Cetauro, A. and Bringel, S.B. and Ferreira, S.J.F. and Silva, M.L.}, title = {Quimiometria aplicada a avaliação química do Igarapé que cruza o polo industrial de Manaus-AM}, journal = {Revista Ibero-Americana de Ciências Ambientais}, year = {2021}, volume = {12}, number = {10} } |
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Lages, A.d.S., Miranda, S.Á.F., Dourado, S.A., Abreu, A.C.d., Bringel, S.R.B., Ferreira, S.J.F. and Silva, M.L.d. | Parâmetros físicos (temperatura, condutividade elétrica e turbidez) na avaliação de corpos de água impactados na área urbana da cidade de Manaus, AM: Physical parameters (temperature, electrical conductivity and turbidity) in the evaluation of impacted water bodies in the urban area of the city of Manaus, AM | 11 | Brazilian Journal of Development Vol. 8(11), pp. 71776-71785 |
article | DOI URL |
Abstract: <p>A Física é uma área de grande alcance na sociedade moderna, contudo, há pouca aplicação em diagnósticos ambientais usando somente variáveis físicas. Diante desse disso, o presente estudo teve por objetivo avaliar três variáveis físicas (temperatura, condutividade elétrica e turbidez) em uma bacia hidrográfica urbana localizada no centro do polo industrial de Manaus – A Bacia Hidrográfica do Educandos – BHE. Foram selecionados nove pontos na BHE e as amostras de águas foram coletadas na superfície dos corpos de águas em frascos de polietileno. As amostras foram conduzidas ao laboratório de Química Ambiental do Instituto Nacional de Pesquisas da Amazônia – INPA. A temperatura da água foi determinada no campo com um termômetro de mercúrio. Condutividade elétrica e turbidez foram analisados por métodos eletroquímicos, com instrumentos de bancada. Os resultados mostraram valores de temperatura acima de 30° C o que sugere falta de arborização nas margens dos corpos de água, valores estes mais elevados que há duas décadas. A condutividade elétrica apresentou valores acima de 400 µS cm<sup>-1</sup> o que denota a grande quantidade de eletrólitos lançados nesses ambientes, caracterizados naturalmente como pouco condutivos, e a turbidez elevada sugere solos revolvidos nas margens. A única exceção foi o ponto P1, que ainda guarda as condições físicas naturais desta bacia hidrográfica.</p> | |||||
BibTeX:
@article{lages_parametros_11, author = {Lages, Anderson da Silva and Miranda, Sebastião Átila Fonseca and Dourado, Sâmia Albuquerque and Abreu, Aretusa Cetauro de and Bringel, Sérgio Roberto Bulcão and Ferreira, Sávio José Filgueiras and Silva, Márcio Luiz da}, title = {Parâmetros físicos (temperatura, condutividade elétrica e turbidez) na avaliação de corpos de água impactados na área urbana da cidade de Manaus, AM: Physical parameters (temperature, electrical conductivity and turbidity) in the evaluation of impacted water bodies in the urban area of the city of Manaus, AM}, journal = {Brazilian Journal of Development}, year = {11}, volume = {8}, number = {11}, pages = {71776--71785}, note = {Section: Original Papers}, url = {https://ojs.brazilianjournals.com.br/ojs/index.php/BRJD/article/view/53939}, doi = {https://doi.org/10.34117/bjdv8n11-069} } |
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Lages, A.d.S., Miranda, S.Á., Ferreira, P.R.G., Mota, F.A.d.C., da Conceição, A.C., Rosas, A.F., Ferreira, S.J.F. and da Silva, M.L. | Índice de Qualidade de Água (IQA) para ambientes amazônicos usando estatística multivariada | 6 | Peer Review Vol. 5(11), pp. 306-323 |
article | DOI URL |
Abstract: <p>O presente trabalho teve por objetivo propor um IQA para as águas ácidas de Manaus usando estatística multivariada. Foi escolhido um local isolado dos grandes centros urbanos para servir de <em>background</em> natural da região. Foram realizadas coletas mensais de água neste igarapé entre os meses de janeiro e julho de 2022 a fim de estabecer marcadores ambientais de naturalidade. Analisou-se 22 variáveis ambientais, e, em seguida, se utilizou a Análise da Componente Principal – ACP para estabecer as variáveis mais importantes do conjunto de dados. Os resultados apontaram que as variáveis que mais se destacaram foram Ntotal, Cl<sup>-</sup>, Na<sup>+ </sup>e condutividade elétrica. A ACP também identificou influência moderada das variáveis NH<sub>4</sub><sup>+</sup>, K<sup>+</sup>, PO<sub>4</sub><sup>3-</sup> e coliformes fecais na compoisção das águas. Criou-se categorias de águas com base em equações exponenciais e logarítimicas despontadas pelas medidas realizadas. Por fim, as equações e curvas foram aplicadas em 12 corpos de água distribuídos na área urbana de Manaus e demonstraram que 75% das amostras avaliadas estavam na condição de péssima.</p> | |||||
BibTeX:
@article{lages_indice_6, author = {Lages, Anderson da Silva and Miranda, Sebastião Átila and Ferreira, Paulo Renan Gomes and Mota, Fábio Alexandre da Costa and da Conceição, Adriana Castro and Rosas, Adriana Freitas and Ferreira, Sávio José Filgueiras and da Silva, Márcio Luiz}, title = {Índice de Qualidade de Água (IQA) para ambientes amazônicos usando estatística multivariada}, journal = {Peer Review}, year = {6}, volume = {5}, number = {11}, pages = {306--323}, note = {Section: Artigos}, url = {https://peerw.org/index.php/journals/article/view/593}, doi = {https://doi.org/10.53660/593.prw1607} } |
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Labat, D., Ronchail, J. and Guyot, J.L. | Recent advances in wavelet analyses: Part 2 - Amazon, Parana, Orinoco and Congo discharges time scale variability | 2005 | Journal of Hydrology Vol. 314(1-4), pp. 289-311 |
article | DOI URL |
Abstract: This paper is devoted to illustrating new wavelet analysis methods in the field of hydrology. New wavelet indicators are applied to long-term hydrological and climatologic proxies. They are first applied to four Atlantic large river monthly discharges (Amazon, Parana, Orinoco and Congo) and then applied to two well-known long-term climatologic indexes: the Southern Oscillation and the North Atlantic Oscillation. This approach makes it possible to suggest physical explanations for time-scale dependant relationships. Six-month variability is present in all the rivers except in the Parana. In the Congo River this signal is near stationary with strong entropy. The strength of this scale coincides with higher discharge variability before 1920 and over the Orinoco basin with higher discharge values between 1940 and 1955. An annual cycle is present in all the rivers but is much stronger, along with the entropy, in the rivers with a large tropical basin, as in the Amazon and the Orinoco. This annual signal is not permanent in the Congo and much more intermittent in the Parana where the annual recharge appears as very irregular. A quasi biennial variability is apparent in all the equator ward rivers and a nearly permanent 2-year coherence is found between Sol and the Amazon discharge. A 3-6year oscillation typical of ENSO variability is observed in all the rivers. It is intermittent, observed before 1930 in all the rivers and after 1980 mostly in the Amazon River. These peaks of activity correspond to periods of major Sol variability. An 8-year variability is particularly strong in the Parana River before 1940 and around 1970 and to a lesser extent in the Orinoco River during the low NAO index period, between 1940 and 1970. The Congo River exhibits that time-scale around 1970. A 13-year variability common to Sol, NAO and the South Atlantic Ocean circulation is observed in the Parana and Congo discharges. In all the rivers the greatest entropy is observed at bi and multi decadal time scales with the greatest coherence with both NAO and Sol. A near 20-year time-scale is observed in most of the series around 1970, although it is strongest in Amazon and Parana discharges. Finally, a 30-year time-scale is observed between 1940 and 1970. It is to be noted that most of the time-scale dominant activities, in all the rivers, may have been influenced by the interdecadal shifts that took place around 1940 and 1970 in the Pacific and in the Atlantic. | |||||
BibTeX:
@article{labat_recent_2005, author = {Labat, D. and Ronchail, J. and Guyot, J. L.}, title = {Recent advances in wavelet analyses: Part 2 - Amazon, Parana, Orinoco and Congo discharges time scale variability}, journal = {Journal of Hydrology}, year = {2005}, volume = {314}, number = {1-4}, pages = {289--311}, url = {://WOS:000233948700022}, doi = {https://doi.org/10.1016/j.jhydrol.2005.04.004} } |
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Labat, D., Ronchail, J., Callede, J., Guyot, J.L., De Oliveira, E. and Guimaraes, W. | Wavelet analysis of Amazon hydrological regime variability | 2004 | Geophysical Research Letters Vol. 31(2) |
article | DOI URL |
Abstract: Wavelet analysis allows for an insightful examination of the temporal variability of Amazon basin hydrology and highlights intermittent interannual and interdecadal fluctuations. Two main conclusions arise. Interannual fluctuations appear as closely related to equatorial Pacific forcings whereas 15-year and bi-decadal fluctuations are strongly correlated with Pacific and tropical Atlantic long term forcings. The 1970's climate shift affects the Amazon basin, implying a correlation between both NATL and SOI and hydrological proxies after that decade. | |||||
BibTeX:
@article{labat_wavelet_2004, author = {Labat, D. and Ronchail, J. and Callede, J. and Guyot, J. L. and De Oliveira, E. and Guimaraes, W.}, title = {Wavelet analysis of Amazon hydrological regime variability}, journal = {Geophysical Research Letters}, year = {2004}, volume = {31}, number = {2}, url = {://WOS:000188866400002}, doi = {https://doi.org/10.1029/2003gl018741} } |
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Kunert, N., Aparecido, L.M.T., Wolff, S., Higuchi, N., Santos, J.d., Araujo, A.C.d. and Trumbore, S. | A revised hydrological model for the Central Amazon: The importance of emergent canopy trees in the forest water budget [BibTeX] |
2017 | Agricultural and Forest Meteorology Vol. 239, pp. 47-57 |
article | |
BibTeX:
@article{kunert_revised_2017, author = {Kunert, Norbert and Aparecido, Luiza Maria T. and Wolff, Stefan and Higuchi, Niro and Santos, Joaquim dos and Araujo, Alessandro Carioca de and Trumbore, Susan}, title = {A revised hydrological model for the Central Amazon: The importance of emergent canopy trees in the forest water budget}, journal = {Agricultural and Forest Meteorology}, year = {2017}, volume = {239}, pages = {47--57} } |
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Kunert, N., Aparecido, L., Higuchi, N., Santos, J.d. and Trumbore, S. | Higher tree transpiration due to road-associated edge effects in a tropical moist lowland forest [BibTeX] |
2015 | Agricultural and Forest Meteorology Vol. 213, pp. 183-192 |
article | |
BibTeX:
@article{kunert_higher_2015, author = {Kunert, N. and Aparecido, L.M.T. and Higuchi, N. and Santos, J. dos and Trumbore, S.}, title = {Higher tree transpiration due to road-associated edge effects in a tropical moist lowland forest}, journal = {Agricultural and Forest Meteorology}, year = {2015}, volume = {213}, pages = {183--192} } |
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Kundu, S., Kawamura, K., Andreae, T.W., Hoffer, A. and Andreae, M.O. | Diurnal variation in the water-soluble inorganic ions, organic carbon and isotopic compositions of total carbon and nitrogen in biomass burning aerosols from the LBA-SMOCC campaign in Rondonia, Brazil | 2010 | Journal of Aerosol Science Vol. 41(1), pp. 118-133 |
article | DOI URL |
Abstract: Aerosol particles (PM(2.5)) were collected during the day (n = 6) and nighttime (n = 9) from a tropical pasture site in Rondonia, Brazil during an intensive biomass burning period (16-26 September, 2002). Higher normalized (by K(+), levoglucosan, or apparent elemental carbon, EC(a)) mass concentrations of SO(4)(2-) and CH(3)SO(3)(-) in daytime suggest their photochemical production, while the opposite trend for NO(3)(-) suggests its transfer to the aerosol phase at lower temperatures and higher humidities, as well as possibly production through hydrolysis of N(2)O(5) on aqueous aerosol particles. About 4.2-7.5% of OC (5-13% of water-soluble organic carbon (WSOC)) could be characterized at the molecular level using GC-MS and GC-FID. Among the detected organic compound classes, abundances of anhydrosugars and aromatics were higher in night samples, but sugars/sugar alcohols, diacids, oxoacids and alpha-dicarbonyls were more abundant in day samples. Consecutive day and night samples showed that delta(13)C values of total carbon (TC) were lower in daytime samples, which can be interpreted as resulting from higher contributions of refractory TC depleted in (13)C due to predominantly flaming combustion. The delta(15)N values of total nitrogen (TN) ranged from +23.5 parts per thousand to +25.7 parts per thousand, however, there was no trend in day and night samples. Higher values of delta(13)C and delta(15)N for biomass burning particles than those of unburned vegetation reflect positive isotopic enrichment either during the formation of particles or after the emission of particles in the atmosphere. (C) 2009 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{kundu_diurnal_2010, author = {Kundu, Shuvashish and Kawamura, Kimitaka and Andreae, Tracey W. and Hoffer, Andras and Andreae, Meinrat O.}, title = {Diurnal variation in the water-soluble inorganic ions, organic carbon and isotopic compositions of total carbon and nitrogen in biomass burning aerosols from the LBA-SMOCC campaign in Rondonia, Brazil}, journal = {Journal of Aerosol Science}, year = {2010}, volume = {41}, number = {1}, pages = {118--133}, url = {://WOS:000274866800012}, doi = {https://doi.org/10.1016/j.jaerosci.2009.08.006} } |
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Kundu, S., Kawamura, K., Andreae, T.W., Hoffer, A. and Andreae, M.O. | Molecular distributions of dicarboxylic acids, ketocarboxylic acids and alpha-dicarbonyls in biomass burning aerosols: implications for photochemical production and degradation in smoke layers | 2010 | Atmospheric Chemistry and Physics Vol. 10(5), pp. 2209-2225 |
article | URL |
Abstract: Aerosols in the size class textless 2.5 mu m (6 daytime and 9 nighttime samples) were collected at a pasture site in Rondonia, Brazil, during the intensive biomass burning period of 16-26 September 2002 as part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Smoke, Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC). Homologous series of dicarboxylic acids (C(2)-C(11)) and related compounds (ketocarboxylic acids and alpha-dicarbonyls) were identified using gas chromatography (GC) and GC/mass spectrometry (GC/MS). Among the species detected, oxalic acid was found to be the most abundant, followed by succinic, malonic and glyoxylic acids. Average concentrations of total dicarboxylic acids, ketocarboxylic acids and alpha-dicarbonyls in the aerosol samples were 2180, 167 and 56 ng m(-3), respectively. These are 2-8, 3-11 and 2-16 times higher, respectively, than those reported in urban aerosols, such as in 14 Chinese megacities. Higher ratios of dicarboxylic acids and related compounds to biomass burning tracers (levoglucosan and K(+)) were found in the daytime than in the nighttime, suggesting the importance of photochemical production. On the other hand, higher ratios of oxalic acid to other dicarboxylic acids and related compounds normalized to biomass burning tracers (levoglucosan and K(+)) in the daytime provide evidence for the possible degradation of dicarboxylic acids (textgreater= C(3)) in this smoke-polluted environment. Assuming that these and related compounds are photo-chemically oxidized to oxalic acid in the daytime, and given their linear relationship, they could account for, on average, 77% of the formation of oxalic acid. The remaining portion of oxalic acid may have been directly emitted from biomass burning as suggested by a good correlation with the biomass burning tracers (K(+), CO and EC(a)) and organic carbon (OC). However, photochemical production from other precursors could not be excluded. | |||||
BibTeX:
@article{kundu_molecular_2010, author = {Kundu, S. and Kawamura, K. and Andreae, T. W. and Hoffer, A. and Andreae, M. O.}, title = {Molecular distributions of dicarboxylic acids, ketocarboxylic acids and alpha-dicarbonyls in biomass burning aerosols: implications for photochemical production and degradation in smoke layers}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {5}, pages = {2209--2225}, url = {://WOS:000275505500009} } |
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Kumarathunge Medlyn, B.E.D.J.E.T.M.G.A.M.J.B.M.C.F.J.K.C.R.C.M.A.C.L.A.C.J.Q.C.K.Y.D.K.M.G.D.D.N.D.E.E.D.S.G.O.H.Q.H.K.J.A.M.K.J.W.K.E.L.M.L.M.O.Y.R.P.B.R.A.S.M.S.N.G.T.L.T.D.T.T.H.F.T.E.S.U.J.V.A.W.G.W.J.M.and.W.D.A.D.P. | Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale [BibTeX] |
2019 | New Phytologist Vol. 222, pp. 768-784 |
article | DOI |
BibTeX:
@article{kumarathunge_acclimation_2019, author = {Kumarathunge, Medlyn, B. E., Drake, J. E., Tjoelker, M. G., Aspinwall, M. J., Battaglia, M., Cano, F. J., Kelsey, C. R., Cavaleri, M. A., Cernusak, L. A., Chambers, J. Q., Crous, K. Y., De Kauwe, M. G., Dillaway, D. N., Dreyer, E., Ellsworth, D. S., Ghannoum, O., Han, Q., Hikosaka, K., Jensen, A. M., Kelly, J. W., Kruger, E. L., Mercado, L. M., Onoda, Y., Reich, P. B., Rogers, A., Slot, M., Smith, N. G., Tarvainen, L., Tissue, D. T., Togashi, H. F., Tribuzy, E. S., Uddling, J., Vårhammar, A., Wallin, G., Warren, J. M. and Way, D. A., D. P.}, title = {Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale}, journal = {New Phytologist}, year = {2019}, volume = {222}, pages = {768--784}, doi = {https://doi.org/10.1111/nph.15668} } |
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Kulmala, M., Artaxo, P. and al , e. | General Overview: European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) - integrating aerosol research from nano to global scales. [BibTeX] |
2011 | Atmos. Chem. Phys. Vol. 11, pp. 13061-13143 |
article | DOI |
BibTeX:
@article{kulmala_general_2011, author = {Kulmala, M. and Artaxo, P. and al, et}, title = {General Overview: European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) - integrating aerosol research from nano to global scales.}, journal = {Atmos. Chem. Phys.}, year = {2011}, volume = {11}, pages = {13061--13143}, doi = {https://doi.org/10.5194/acp-11-13061-2011} } |
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Kuhn, U., Rottenberger, S., Biesenthal, T., Wolf, A., Schebeske, G., Ciccioli, P. and Kesselmeier, J. | Strong correlation between isoprene emission and gross photosynthetic capacity during leaf phenology of the tropical tree species Hymenaea courbaril with fundamental changes in volatile organic compounds emission composition during early leaf development | 2004 | Plant Cell and Environment Vol. 27(12), pp. 1469-1485 |
article | DOI URL |
Abstract: Changes of the volatile organic compounds (VOC) emission capacity and composition of different developmental stages of the tropical tree species Hymenaea courbaril were investigated under field conditions at a remote Amazonian rainforest site. The basal emission capacity of isoprene changed considerably over the course of leaf development, from young to mature and to senescent leaves, ultimately spanning a wide range of observed isoprene basal emission capacities from 0.7 to 111.5 mug C g(-1) h(-1) during the course of the year. By adjusting the standard emission factors for individual days, the diel courses of instantaneous isoprene emission rates could nevertheless adequately be modelled by a current isoprene algorithm. The results demonstrate the inadequacy of using one single standard emission factor to represent the VOC emission capacity of tropical vegetation for an entire seasonal cycle. A strong linear correlation between the isoprene emission capacity and the gross photosynthetic capacity (GP(max)) covering all developmental stages and seasons was observed. The present results provide evidence that leaf photosynthetic properties may confer a valuable basis to model the seasonal variation of isoprenoid emission capacity; especially in tropical regions where the environmental conditions vary less than in temperate regions. In addition to induction and variability of isoprene emission during early leaf development, considerable amounts of monoterpenes were emitted in a light-dependent manner exclusively in the period between bud break and leaf maturity. The fundamental change in emission composition during this stage as a consequence of resource availability (supply side control) or as a plant's response to the higher defence demand of young emerging leaves (demand-side control) is discussed. The finding of a temporary emergence of monoterpene emission may be of general interest in understanding both the ecological functions of isoprenoid production and the regulatory processes involved. | |||||
BibTeX:
@article{kuhn_strong_2004, author = {Kuhn, U. and Rottenberger, S. and Biesenthal, T. and Wolf, A. and Schebeske, G. and Ciccioli, P. and Kesselmeier, J.}, title = {Strong correlation between isoprene emission and gross photosynthetic capacity during leaf phenology of the tropical tree species Hymenaea courbaril with fundamental changes in volatile organic compounds emission composition during early leaf development}, journal = {Plant Cell and Environment}, year = {2004}, volume = {27}, number = {12}, pages = {1469--1485}, url = {://WOS:000225487500003}, doi = {https://doi.org/10.1111/j.1365-3040.2004.01252.x} } |
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Kuhn, U., Rottenberger, S., Biesenthal, T., Wolf, A., Schebeske, G., Ciccioli, P., Brancaleoni, E., Frattoni, M., Tavares, T.M. and Kesselmeier, J. | Seasonal differences in isoprene and light-dependent monoterpene emission by Amazonian tree species | 2004 | Global Change Biology Vol. 10(5), pp. 663-682 |
article | DOI URL |
Abstract: Whereas for extra-tropical regions model estimates of the emission of volatile organic compounds (VOC) predict strong responses to the strong annual cycles of foliar biomass, light intensity and temperature, the tropical regions stand out as a dominant source year round, with only little variability mainly due to the annual cycle of foliar biomass of drought-deciduous trees. As part of the Large Scale Biosphere Atmosphere Experiment in Amazonia (LBA-EUSTACH), a remote secondary tropical forest site was visited in the dry-to-wet season transition campaign, and the trace gas exchange of a strong isoprene emitter and a monoterpene emitter are compared to the wet-to-dry season transition investigations reported earlier. Strong seasonal differences of the emission capacity were observed. The standard emission factor for isoprene emission of young mature leaves of Hymenaea courbaril was about twofold in the end of the dry season (111.5 mugC g(-1) h(-1) or 41.2 nmol m(-2) s(-1)) compared to old mature leaves investigated in the end of the wet season (45.4 mugC g(-1) h(-1) or 24.9 nmol m(-2) s(-1)). Standardized monoterpene emission rate of Apeiba tibourbou were 2.1 and 3.6 mugC g(-1) h(-1) (or 0.3 and 0.8 nmol m(-2) s(-1)), respectively. This change in species-specific VOC emission capacity was mirrored by a concurrent change in the ambient mixing ratios. The growth conditions vary less in tropical areas than in temperate regions of the world, and the seasonal differences in emission strength could not be reconciled solely with meteorological data of instantaneous light intensity and temperature. Hence the inadequacy of using a single standard emission factor to represent an entire seasonal cycle is apparent. Among a host of other potential factors, including the leaf developmental stage, water and nutrient status, and abiotic stresses like the oxidative capacity of the ambient air, predominantly the long-term growth temperature may be applied to predict the seasonal variability of the isoprene emission capacity. The dry season isoprene emission rates of H. courbaril measured at the canopy top were also compared to isoprene emissions of the shade-adapted species Sorocea guilleminiana growing in the understory. Despite the difference in VOC emission composition and canopy position, one common algorithm was able to predict the diel emission pattern of all three tree species. | |||||
BibTeX:
@article{kuhn_seasonal_2004, author = {Kuhn, U. and Rottenberger, S. and Biesenthal, T. and Wolf, A. and Schebeske, G. and Ciccioli, P. and Brancaleoni, E. and Frattoni, M. and Tavares, T. M. and Kesselmeier, J.}, title = {Seasonal differences in isoprene and light-dependent monoterpene emission by Amazonian tree species}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {663--682}, url = {://WOS:000221421600010}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00771.x} } |
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Kuhn, U., Rottenberger, S., Biesenthal, T., Wolf, A., Schebeske, G., Ciccioli, P., Brancaleoni, E., Frattoni, M., Tavares, T.M. and Kesselmeier, J. | Isoprene and monoterpene emissions of Amazonian tree species during the wet season: Direct and indirect investigations on controlling environmental functions | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: As part of the project LBA-EUSTACH (European Studies on Trace gases and Atmosphere Chemistry as a contribution to the Large-Scale Biosphere-Atmosphere experiment in Amazonia), we examined the diel pattern of isoprenoid exchange in the wet season of 1999 at a remote field site in Rondonia, Brazil. The emission pattern of two tree species in a secondary forest was investigated by means of a dynamic branch enclosure system and was compared on the basis of climatological variables like temperature and light and physiological parameters such as assimilation, transpiration, and stomatal conductance. While the species Hymenaea courbaril was found to be a strong isoprene emitter, Apeiba tibourbou was found to exclusively emit monoterpenes and no isoprene. Species-related standard emission factors calculated on a carbon basis were 45.4 mug g(-1) h(-1) (24.9 nmol m(-2) s(-1)) for isoprene and 3.6 mug g(-1) h(-1) (0.75 nmol m(-2) s(-1)) for monoterpene emission, representing a nontrivial carbon loss by the plants of 1.8% and 0.1% C relative to the net carbon assimilation on a daily basis. About 90% of the total monoterpene emission from A. tibourbou was comprised of sabinene, alpha-pinene, beta-pinene, myrcene, and limonene, in decreasing quantity. Despite the difference in isoprenoid emission composition, the diel emission pattern of both tree species reacted similarly toward the environmental conditions, fluctuating light and temperature, indicating that closely related metabolic controls were involved in the actual emission. Both isoprene emission and monoterpene emission exhibited a light saturation curve similar to CO(2) assimilation. No isoprenoid emission was found during nighttime. The strong light dependence of the monoterpene emission by A. tibourbou suggests that this tree species does not store monoterpenes but emits them immediately upon production. The diel pattern of both the isoprene and the monoterpene emission could be adequately simulated by current isoprene algorithms. The ambient air mixing ratios of isoprenoids were clearly dominated by isoprene, with peak values of 8 ppb inside the main canopy. Vertical gradients of ambient air mixing ratios in and above a primary rain forest site illustrated the emission of isoprene by the main canopy dependent upon light and temperature but were also indicative of a potential sink at the forest floor. For monoterpenes, corresponding gradients could hardly be resolved, reflecting observed ambient air mixing ratios more than an order of magnitude lower than for isoprene. Nevertheless, a strong diel cycle of short-lived monoterpene compounds like alpha-pinene was found in the primary as well as in the secondary forest site, which further strengthens our finding of a strong light dependence of biogenic monoterpene emission even on a larger scale. Our findings to some extent question the applicability of the commonly used monoterpene emission algorithm to the tropics. A strong light dependence of biogenic monoterpene emissions may, if generalized for tropical tree species in common, have a strong impact on estimated global flux rates for tropical regions. | |||||
BibTeX:
@article{kuhn_isoprene_2002, author = {Kuhn, U. and Rottenberger, S. and Biesenthal, T. and Wolf, A. and Schebeske, G. and Ciccioli, P. and Brancaleoni, E. and Frattoni, M. and Tavares, T. M. and Kesselmeier, J.}, title = {Isoprene and monoterpene emissions of Amazonian tree species during the wet season: Direct and indirect investigations on controlling environmental functions}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200027}, doi = {https://doi.org/10.1029/2001jd000978} } |
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Kuhn, U., Rottenberger, S., Biesenthal, T., Ammann, C., Wolf, A., Schebeske, G., Oliva, S.T., Tavares, T.M. and Kesselmeier, J. | Exchange of short-chain monocarboxylic acids by vegetation at a remote tropical forest site in Amazonia | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: As part of the project LBA-EUSTACH (European Studies on Trace gases and Atmospheric Chemistry as a contribution to the Large-Scale Biosphere-Atmosphere experiment in Amazonia), the exchange of formic acid and acetic acid between vegetation and the atmosphere was investigated in the wet-to-dry season transition and the dry-to-wet season transition periods in 1999 in Rondonia, Brazil. Direct exchange measurements on the branch level mainly exhibited uptake of formic acid and acetic acid for all plant species in both seasons, although diel, seasonal, and interspecies variations were observed. Even though other physiological and physico-chemical parameters may have contributed, the uptake of organic acids was found to be primarily a function of the ambient atmospheric mixing ratios. The linear dependence suggests a bidirectional exchange behavior of the plants and calculated deposition velocities (0.17-0.23 cm s(-1)), compensation point mixing ratios (0.16-0.30 ppb), and potential emission rates under purified air conditions (0.013-0.031 nmol m(-2) s(-1)) are discussed. Vertical profile measurements in and above the primary forest canopy further strengthened the assumption that the forest is rather a sink than a source for organic acids. The generally lower mixing ratios observed within the canopy were indicative of an uptake by vegetation and/or the soil surface. Continuous measurements of the ambient atmospheric mixing ratios at the canopy top revealed strong diel variations in both seasons and a marked seasonality with higher mixing ratios during the dry season, both being mirrored in the variation of observed uptake rates of the plants. High atmospheric concentrations during the dry season were attributed to biomass burning. During the wet season, when biomass burning activity was low, indirect emission by the vegetation, i.e., photochemical oxidation of primarily emitted biogenic reactive hydrocarbons, was assumed to dominantly contribute to the atmospheric burden of the organic acids. The high degree of correlation between atmospheric formic acid and acetic acid indicated that similar atmospheric processes were affecting their mixing ratios. | |||||
BibTeX:
@article{kuhn_exchange_2002, author = {Kuhn, U. and Rottenberger, S. and Biesenthal, T. and Ammann, C. and Wolf, A. and Schebeske, G. and Oliva, S. T. and Tavares, T. M. and Kesselmeier, J.}, title = {Exchange of short-chain monocarboxylic acids by vegetation at a remote tropical forest site in Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200025}, doi = {https://doi.org/10.1029/2000jd000303} } |
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Kuhn, U., Ganzeveld, L., Thielmann, A., Dindorf, T., Schebeske, G., Welling, M., Sciare, J., Roberts, G., Meixner, F.X., Kesselmeier, J., Lelieveld, J., Kolle, O., Ciccioli, P., Lloyd, J., Trentmann, J., Artaxo, P. and Andreae, M.O. | Impact of Manaus City on the Amazon Green Ocean atmosphere: ozone production, precursor sensitivity and aerosol load | 2010 | Atmospheric Chemistry and Physics Vol. 10(19), pp. 9251-9282 |
article | DOI URL |
Abstract: As a contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE-2001) field campaign in the heart of the Amazon Basin, we analyzed the temporal and spatial dynamics of the urban plume of Manaus City during the wet-to-dry season transition period in July 2001. During the flights, we performed vertical stacks of crosswind transects in the urban outflow downwind of Manaus City, measuring a comprehensive set of trace constituents including O(3), NO, NO(2), CO, VOC, CO(2), and H(2)O. Aerosol loads were characterized by concentrations of total aerosol number (CN) and cloud condensation nuclei (CCN), and by light scattering properties. Measurements over pristine rainforest areas during the campaign showed low levels of pollution from biomass burning or industrial emissions, representative of wet season background conditions. The urban plume of Manaus City was found to be joined by plumes from power plants south of the city, all showing evidence of very strong photochemical ozone formation. One episode is discussed in detail, where a threefold increase in ozone mixing ratios within the atmospheric boundary layer occurred within a 100 km travel distance downwind of Manaus. Observation-based estimates of the ozone production rates in the plume reached 15 ppb h(-1). Within the plume core, aerosol concentrations were strongly enhanced, with Delta CN/Delta CO ratios about one order of magnitude higher than observed in Amazon biomass burning plumes. Delta CN/Delta CO ratios tended to decrease with increasing transport time, indicative of a significant reduction in particle number by coagulation, and without substantial new particle nucleation occurring within the time/space observed. While in the background atmosphere a large fraction of the total particle number served as CCN (about 60-80% at 0.6% supersaturation), the CCN/CN ratios within the plume indicated that only a small fraction (16 +/- 12 %) of the plume particles were CCN. The fresh plume aerosols showed relatively weak light scattering efficiency. The CO-normalized CCN concentrations and light scattering coefficients increased with plume age in most cases, suggesting particle growth by condensation of soluble organic or inorganic species. We used a Single Column Chemistry and Transport Model (SCM) to infer the urban pollution emission fluxes of Manaus City, implying observed mixing ratios of CO, NO(x) and VOC. The model can reproduce the temporal/spatial distribution of ozone enhancements in the Manaus plume, both with and without accounting for the distinct (high NO(x)) contribution by the power plants; this way examining the sensitivity of ozone production to changes in the emission rates of NO(x). The VOC reactivity in the Manaus region was dominated by a high burden of biogenic isoprene from the background rainforest atmosphere, and therefore NO(x) control is assumed to be the most effective ozone abatement strategy. Both observations and models show that the agglomeration of NO(x) emission sources, like power plants, in a well-arranged area can decrease the ozone production efficiency in the near field of the urban populated cores. But on the other hand remote areas downwind of the city then bear the brunt, being exposed to increased ozone production and N-deposition. The simulated maximum stomatal ozone uptake fluxes were 4 nmol m(-2) s(-1) close to Manaus, and decreased only to about 2 nmol m(-2) s(-1) within a travel distance textgreater1500 km downwind from Manaus, clearly exceeding the critical threshold level for broadleaf trees. Likewise, the simulated N deposition close to Manaus was similar to 70 kg N ha(-1) a(-1) decreasing only to about 30 kg N ha(-1) a(-1) after three days of simulation. | |||||
BibTeX:
@article{kuhn_impact_2010, author = {Kuhn, U. and Ganzeveld, L. and Thielmann, A. and Dindorf, T. and Schebeske, G. and Welling, M. and Sciare, J. and Roberts, G. and Meixner, F. X. and Kesselmeier, J. and Lelieveld, J. and Kolle, O. and Ciccioli, P. and Lloyd, J. and Trentmann, J. and Artaxo, P. and Andreae, M. O.}, title = {Impact of Manaus City on the Amazon Green Ocean atmosphere: ozone production, precursor sensitivity and aerosol load}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {19}, pages = {9251--9282}, url = {://WOS:000283066300003}, doi = {https://doi.org/10.5194/acp-10-9251-2010} } |
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Kuhn, U., Dindorf, T., Ammann, C., Rottenberger, S., Guyon, P., Holzinger, R., Ausma, S., Kenntner, T., Helleis, F. and Kesselmeier, J. | Design and field application of an automated cartridge sampler for VOC concentration and flux measurements | 2005 | Journal of Environmental Monitoring Vol. 7(6), pp. 568-576 |
article | DOI URL |
Abstract: One of the major limitations in advancing the understanding of tropospheric ozone and aerosol generation and developing strategies for their control is the technical ability to accurately measure volatile organic compounds (VOCs). This paper describes the design of a constant flow VOC sampler. The versatile sampler can be used for fully automated concentration and flux measurements of VOCs. The sampler incorporates a microprocessor control unit and provides highly accurate mass flow control and significant ease of operation. Sampling sequences can be programmed directly or by remote control through a PC. All important operational parameters necessary for a complete sampling audit trail are logged. Compact weatherproof housings and low power consumption allow operation at remote sites and locations which are sensitive to disturbances or have restricted access. Inner wetted surfaces of the sampler are constructed from non-contaminating materials that do not sorb or emit VOC, and thus permit the collection of representative samples even in environments with very low VOC concentrations. The cartridge magazine provides a maximum of 20 sequential cartridge samples, which allows for long-term air quality assessments. In the dual channel mode, two samples can be collected simultaneously through two independent sample loops, providing ten sequential sample pairs. This design allows the parallel collection of (a) quality assurance backup samples, (b) samples on two different types of cartridges/sorbents to allow a variety of analyses, or (c) differential samples for flux measurements using enclosure, aerodynamic profile, or relaxed eddy accumulation (REA) methods. Field applications including airplane profile measurements above a tropical rainforest area, as well as gradient and REA measurements over a mid-latitude mixed forest stand are described, and demonstrate the validity and flexibility of the system. In particular, the application of the VOC sampler as an integrated part of a REA system is emphasized. | |||||
BibTeX:
@article{kuhn_design_2005, author = {Kuhn, U. and Dindorf, T. and Ammann, C. and Rottenberger, S. and Guyon, P. and Holzinger, R. and Ausma, S. and Kenntner, T. and Helleis, F. and Kesselmeier, J.}, title = {Design and field application of an automated cartridge sampler for VOC concentration and flux measurements}, journal = {Journal of Environmental Monitoring}, year = {2005}, volume = {7}, number = {6}, pages = {568--576}, note = {Edition: 2005/06/03}, url = {://WOS:000230928100014}, doi = {https://doi.org/10.1039/b500057b} } |
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Kuhn, U., Andreae, M.O., Ammann, C., Araujo, A.C., Brancaleoni, E., Ciccioli, P., Dindorf, T., Frattoni, M., Gatti, L.V., Ganzeveld, L., Kruijt, B., Lelieveld, J., Lloyd, J., Meixner, F.X., Nobre, A.D., Poschl, U., Spirig, C., Stefani, P., Thielmann, A., Valentini, R. and Kesselmeier, J. | Isoprene and monoterpene fluxes from Central Amazonian rainforest inferred from tower-based and airborne measurements, and implications on the atmospheric chemistry and the local carbon budget | 2007 | Atmospheric Chemistry and Physics Vol. 7(11), pp. 2855-2879 |
article | URL |
Abstract: We estimated the isoprene and monoterpene source strengths of a pristine tropical forest north of Manaus in the central Amazon Basin using three different micrometeorological flux measurement approaches. During the early dry season campaign of the Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE-2001), a tower-based surface layer gradient (SLG) technique was applied simultaneously with a relaxed eddy accumulation ( REA) system. Airborne measurements of vertical profiles within and above the convective boundary layer (CBL) were used to estimate fluxes on a landscape scale by application of the mixed layer gradient (MLG) technique. The mean daytime fluxes of organic carbon measured by REA were 2.1 mg C m(-2) h(-1) for isoprene, 0.20 mg C m(-2) h(-1) for alpha-pinene, and 0.39 mg C m(-2) h(-1) for the sum of monoterpenes. These values are in reasonable agreement with fluxes determined with the SLG approach, which exhibited a higher scatter, as expected for the complex terrain investigated. The observed VOC fluxes are in good agreement with simulations using a single-column chemistry and climate model (SCM). In contrast, the model-derived mixing ratios of VOCs were by far higher than observed, indicating that chemical processes may not be adequately represented in the model. The observed vertical gradients of isoprene and its primary degradation products methyl vinyl ketone (MVK) and methacrolein (MACR) suggest that the oxidation capacity in the tropical CBL is much higher than previously assumed. A simple chemical kinetics model was used to infer OH radical concentrations from the vertical gradients of (MVK+MACR)/isoprene. The estimated range of OH concentrations during the daytime was 3-8 x 10(6) molecules cm(-3), i.e., an order of magnitude higher than is estimated for the tropical CBL by current state-of-the-art atmospheric chemistry and transport models. The remarkably high OH concentrations were also supported by results of a simple budget analysis, based on the flux-to-lifetime relationship of isoprene within the CBL. Furthermore, VOC fluxes determined with the airborne MLG approach were only in reasonable agreement with those of the tower-based REA and SLG approaches after correction for chemical decay by OH radicals, applying a best estimate OH concentration of 5.5 x 10(6) molecules cm(-3). The SCM model calculations support relatively high OH concentration estimates after specifically being constrained by the mixing ratios of chemical constituents observed during the campaign. The relevance of the VOC fluxes for the local carbon budget of the tropical rainforest site during the measurements campaign was assessed by comparison with the concurrent CO(2) fluxes, estimated by three different methods ( eddy correlation, Lagrangian dispersion, and mass budget approach). Depending on the CO(2) flux estimate, 1 - 6% or more of the carbon gained by net ecosystem productivity appeared to be re-emitted through VOC emissions. |
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BibTeX:
@article{kuhn_isoprene_2007, author = {Kuhn, U. and Andreae, M. O. and Ammann, C. and Araujo, A. C. and Brancaleoni, E. and Ciccioli, P. and Dindorf, T. and Frattoni, M. and Gatti, L. V. and Ganzeveld, L. and Kruijt, B. and Lelieveld, J. and Lloyd, J. and Meixner, F. X. and Nobre, A. D. and Poschl, U. and Spirig, C. and Stefani, P. and Thielmann, A. and Valentini, R. and Kesselmeier, J.}, title = {Isoprene and monoterpene fluxes from Central Amazonian rainforest inferred from tower-based and airborne measurements, and implications on the atmospheric chemistry and the local carbon budget}, journal = {Atmospheric Chemistry and Physics}, year = {2007}, volume = {7}, number = {11}, pages = {2855--2879}, url = {://000247261000006} } |
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Kuczak, C.N., Fernandes, E.C.M., Lehmann, J., Rondon, M.A. and Luizao, F.J. | Inorganic and organic phosphorus pools in earthworm casts (Glossoscolecidae) and a Brazilian rainforest Oxisol | 2006 | Soil Biology & Biochemistry Vol. 38(3), pp. 553-560 |
article | DOI URL |
Abstract: We compared differences in soil phosphorus fractions between large earthworm casts (Family Glossoscolecidae) and surrounding soils, i.e., Oxisols in 10 year-old upland agroforestry system (AGR), pasture (PAS), and secondary forest (SEC) in the Central Brazilian Amazon. AGR and PAS both received low-input fertilization and SEC received no fertilization. We found that earthworm casts had higher levels of organic hydroxide P than surrounding soils, whereas fertilization increased inorganic hydroxide P. Inorganic P was increased by fertilization, and organic P was increased by earthworm gut passage and/or selection of ingested materials, which increased available P (sum of resin and bicarbonate fractions) and moderately available P (sum of hydroxide and dilute acid fractions), and P fertilizer application and land-use increased available P. The use of a modified sequential P fractionation produced fewer differences between earthworm casts and soils than were expected. We suggest the use of a condensed extraction procedure with three fractions (Available P, Moderately Available P, and Resistant P) that provide an ecologically based understanding of the P availability in soil. Earthworm casts were estimated to constitute 41.0, 38.2, and 26.0 kg ha(-1) of total available P stocks (sum of resin and bicarbonate fractions) in the agroforestry system, pasture, and secondary forest, respectively. Published by Elsevier Ltd. | |||||
BibTeX:
@article{kuczak_inorganic_2006, author = {Kuczak, C. N. and Fernandes, E. C. M. and Lehmann, J. and Rondon, M. A. and Luizao, F. J.}, title = {Inorganic and organic phosphorus pools in earthworm casts (Glossoscolecidae) and a Brazilian rainforest Oxisol}, journal = {Soil Biology & Biochemistry}, year = {2006}, volume = {38}, number = {3}, pages = {553--560}, url = {://WOS:000236157300015}, doi = {https://doi.org/10.1016/j.soilbio.2005.06.007} } |
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Kubatova, A., Vermeylen, R., Claeys, M., Cafmeyer, J., Maenhaut, W., Roberts, G. and Artaxo, P. | Carbonaceous aerosol characterization in the Amazon basin, Brazil: novel dicarboxylic acids and related compounds | 2000 | Atmospheric Environment Vol. 34(29-30), pp. 5037-5051 |
article | DOI URL |
Abstract: High-resolution capillary gas chromatography (GC) and GC/mass spectrometry (MS) were employed for the quantitative determination of dichloromethane-extractable organic compounds in total and size-fractionated aerosol samples which were collected in the Amazon basin, Brazil, during the wet season, as part of the LBA-CLAIRE-98 experiment. Special emphasis was placed on the characterization and identification of several novel unknown dicarboxylic acids and related oxidative degradation products. This class of acidic products was enriched in the fine size fraction, suggesting that they were secondary organic aerosol products formed by gas-to-particle conversion. Some of the unknowns contributed more to the class of dicarboxylic acids than the major known compound, nonadioic acid (azelaic acid). The same unknowns were also observed in urban aerosol samples collected on hot summer days in Gent, Belgium. For the characterization and structure elucidation of the unknowns, various types of derivatizations and Fractionation by solid-phase extraction were employed in combination with GC/MS. Four unknowns were identified. The most abundant were two derivatives of glutaric acid, 3-isopropyl pentanedioic acid and 3-acetyl pentanedioic acid. The other two identified unknowns were another oxo homologue, 3-acetyl hexanedioic acid, and, interestingly, 3-carboxy heptanedioic acid. To our knowledge, the occurrence of these four compounds in atmospheric aerosols has not yet been reported. The biogenic precursors of the novel identified compounds could not be pinpointed. but most likely include monoterpenes and fatty acids. (C) 2000 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{kubatova_carbonaceous_2000, author = {Kubatova, A. and Vermeylen, R. and Claeys, M. and Cafmeyer, J. and Maenhaut, W. and Roberts, G. and Artaxo, P.}, title = {Carbonaceous aerosol characterization in the Amazon basin, Brazil: novel dicarboxylic acids and related compounds}, journal = {Atmospheric Environment}, year = {2000}, volume = {34}, number = {29-30}, pages = {5037--5051}, url = {://WOS:000165259600008}, doi = {https://doi.org/10.1016/s1352-2310(00)00320-4} } |
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Krusche, A.V., Ballester, M.V.R. and Leite, N.K. | Hydrology and Biogeochemistry of Terra Firme Lowland Tropical Forests [BibTeX] |
2011 | Vol. 216Forest Hydrology and Biogeochemistry: Synthesis of Past Research and Future Directions, pp. 187-201 |
incollection | DOI URL |
BibTeX:
@incollection{levia_hydrology_2011, author = {Krusche, Alex V. and Ballester, Maria Victoria R. and Leite, Nei K.}, title = {Hydrology and Biogeochemistry of Terra Firme Lowland Tropical Forests}, booktitle = {Forest Hydrology and Biogeochemistry: Synthesis of Past Research and Future Directions}, year = {2011}, volume = {216}, pages = {187--201}, url = {://WOS:000292894600010}, doi = {https://doi.org/10.1007/978-94-007-1363-5_9} } |
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Krusche, B., M.V.R., V., Bernardes, R.L., Leite, M.C., Hanada, N.K., Victoria, L.S., Toledo, D.C., Ometto, A.M., Moreira, J.P., Gomes, M.Z., Bolson, B.M., Neto, M.A., Bonelli, S.G., Deegan, N., Neill, L., Thomas, C., Aufdenkampe, S., Richey, A.K. and A.V., J.E. | Efeitos das mudanças do uso da terra na biogeoquímica dos corpos d'água da bacia do rio Ji-Paraná, Rondônia [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 197 - 205 |
article | |
BibTeX:
@article{krusche_efeitos_2005, author = {Krusche, Ballester, M.V.R., Victoria, R.L., Bernardes, M.C., Leite, N.K., Hanada, L.S., Victoria, D.C., Toledo, A.M., Ometto, J.P., Moreira, M.Z., Gomes, B.M., Bolson, M.A., Neto, S.G., Bonelli, N., Deegan, L., Neill, C., Thomas, S., Aufdenkampe, A.K., Richey, J.E., A.V.}, title = {Efeitos das mudanças do uso da terra na biogeoquímica dos corpos d'água da bacia do rio Ji-Paraná, Rondônia}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {197 -- 205} } |
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Kruijt, B., Malhi, Y., Lloyd, J., Norbre, A.D., Miranda, A.C., Pereira, M.G.P., Culf, A. and Grace, J. | Turbulence statistics above and within two Amazon rain forest canopies | 2000 | Boundary-Layer Meteorology Vol. 94(2), pp. 297-331 |
article | DOI URL |
Abstract: The turbulence structure in two Amazon rain forests was characterised for a range of above-canopy stability conditions, and the results compared with previous studies in other forest canopies and recent theory for the generation of turbulent eddies just above forest canopies. Three-dimensional wind speed and temperature fluctuation data were collected simultaneously at up to five levels inside and above two canopies of 30-40 m tall forests, during three separate periods. We analysed hourly statistics, joint probability distributions, length scales, spatial correlations and coherence, as well as power spectra of vertical and horizontal wind speed. The daytime results show a sharp attenuation of turbulence in the top third of the canopies, resulting in very little movement, and almost Gaussian probability distributions of wind speeds, in the lower canopy. This contrasts with strongly skewed and kurtotic distributions in the upper canopy. At night, attenuation was even stronger and skewness vanished even in the upper canopy. Power spectral peaks in the lower canopy are shifted to lower frequencies relative to the upper canopy, and spatial correlations and coherences were low throughout the canopy. Integral length scales of vertical wind speed at the top of the canopy were small, about 0.15 h compared to a value of 0.28 h expected from the shear length scale at the canopy top, based on the hypothesis that the upper canopy air behaves as a plane mixing layer. All this suggests that, although exchange is not totally inhibited, tropical rain forest canopies differ from other forests in that rapid, coherent downward sweeps do not penetrate into the lower canopy, and that length scales are suppressed. This is associated with a persistent inversion of stability in that region compared to above-canopy conditions. The inversion is likely to be maintained by strong heat absorption in the leaves concentrated near the canopy top, with the generally weak turbulence being unable to destroy the temperature gradients over the large canopy depth. | |||||
BibTeX:
@article{kruijt_turbulence_2000, author = {Kruijt, B. and Malhi, Y. and Lloyd, J. and Norbre, A. D. and Miranda, A. C. and Pereira, M. G. P. and Culf, A. and Grace, J.}, title = {Turbulence statistics above and within two Amazon rain forest canopies}, journal = {Boundary-Layer Meteorology}, year = {2000}, volume = {94}, number = {2}, pages = {297--331}, url = {://WOS:000085008200005}, doi = {https://doi.org/10.1023/a:1002401829007} } |
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Kruijt, B., Elbers, J.A., von Randow, C., Araujo, A.C., Oliveira, P.J., Culf, A., Manzi, A.O., Nobre, A.D., Kabat, P. and Moors, E.J. | The robustness of eddy correlation fluxes for Amazon rain forest conditions | 2004 | Ecological Applications Vol. 14(4), pp. S101-S113 |
article | URL |
Abstract: We analyzed errors and uncertainties in time-integrated eddy correlation data for sites in the Amazon. A well-known source of potential error in eddy correlation is through possible advective losses of CO2 emissions during calm nights. There are also que. stions related to the treatment of low frequencies, non-horizontal flow, and uncertainties in, e.g., corrections for tube delay and frequency loss, as well as the effect of missing data. In this study, we systematically explore these issues for the specific situation of flux measurements at two Amazon forest sites. Results indicate that, for this specific environment with tall forest and tall towers, errors and uncertainties caused by data spikes, delay corrections, and high-frequency loss are small (textless3% on an annual basis). However, sensitivities to the treatment of low frequencies and non-horizontal flow can be large, especially if the landscape is not homogeneous. Given that there is no consensus on methodology here, this represents an uncertainty of 10-25% on annual total carbon, uptake. The other large uncertainty is clearly in the nighttime fluxes. Two different ways to evaluate the validity of these fluxes resulted in at least a 100% difference of annual totals. Finally, we show that,uncertainty (standard errors) associated with data gaps can be reduced to textless0.5 Mg(.)ha(-1.)yr(-1) if data are covering at least half of the time, with random spread. Overall uncertainty, on annual CO2 fluxes, excluding the nighttime dilemma, is estimated at +/-12% (central Amazon site) to +/-32% (southwest Amazon site). Additionally, the nighttime uncertainty is of similar magnitude as the time-integrated fluxes themselves. | |||||
BibTeX:
@article{kruijt_robustness_2004, author = {Kruijt, B. and Elbers, J. A. and von Randow, C. and Araujo, A. C. and Oliveira, P. J. and Culf, A. and Manzi, A. O. and Nobre, A. D. and Kabat, P. and Moors, E. J.}, title = {The robustness of eddy correlation fluxes for Amazon rain forest conditions}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S101--S113}, url = {://WOS:000223269000010} } |
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Krejci, R., Strom, J., de Reus, M., Williams, J., Fischer, H., Andreae, M.O. and Hansson, H.C. | Spatial and temporal distribution of atmospheric aerosols in the lowermost troposphere over the Amazonian tropical rainforest | 2005 | Atmospheric Chemistry and Physics Vol. 5, pp. 1527-1543 |
article | URL |
Abstract: We present measurements of aerosol physicochemical properties below 5 km altitude over the tropical rain forest and the marine boundary layer (MBL) obtained during the LBA-CLAIRE 1998 project. The MBL aerosol size distribution some 50-100 km of the coast of French Guyana and Suriname showed a bi-modal shape typical of aged and cloud processed aerosol. The average particle number density in the MBL was 383 cm(-3). The daytime mixed layer height over the rain forest for undisturbed conditions was estimated to be between 1200-1500 m. During the morning hours the height of the mixed layer increased by 144-180 m h(-1). The median daytime aerosol number density in the mixed layer increased from 450 cm(-3) in the morning to almost 800 cm(-3) in the late afternoon. The evolution of the aerosol size distribution in the daytime mixed layer over the rain forest showed two distinct patterns. Between dawn and midday, the Aitken mode particle concentrations increased, whereas later during the day, a sharp increase of the accumulation mode aerosol number densities was observed, resulting in a doubling of the morning accumulation mode concentrations from 150 cm(-3) to 300 cm(-3). Potential sources of the Aitken mode particles are discussed here including the rapid growth of ultrafine aerosol particles formed aloft and subsequently entrained into the mixed layer, as well as the contribution of emissions from the tropical vegetation to Aitken mode number densities. The observed increase of the accumulation mode aerosol number densities is attributed to the combined effect of: the direct emissions of primary biogenic particles from the rain forest and aerosol in-cloud processing by shallow convective clouds. Based on the similarities among the number densities, the size distributions and the composition of the aerosol in the MBL and the nocturnal residual layer we propose that the air originating in the MBL is transported above the nocturnal mixed layer up to 300-400 km inland over the rain forest by night without significant processing. | |||||
BibTeX:
@article{krejci_spatial_2005, author = {Krejci, R. and Strom, J. and de Reus, M. and Williams, J. and Fischer, H. and Andreae, M. O. and Hansson, H. C.}, title = {Spatial and temporal distribution of atmospheric aerosols in the lowermost troposphere over the Amazonian tropical rainforest}, journal = {Atmospheric Chemistry and Physics}, year = {2005}, volume = {5}, pages = {1527--1543}, url = {://WOS:000229889600003} } |
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Krejci, R., Strom, J., de Reus, M., Hoor, P., Williams, J., Fischer, H. and Hansson, H.C. | Evolution of aerosol properties over the rain forest in Surinam, South America, observed from aircraft during the LBA-CLAIRE 98 experiment | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D18) |
article | DOI URL |
Abstract: [1] As part of the Large-Scale Biosphere- Atmosphere Experiment in Amazonia (LBA)Cooperative LBA Airborne Regional Experiment, airborne measurements of aerosol properties over the northeast Amazonian rain forest at an altitude range between 0.2 and 12.6 km were performed in March 1998. The particle number densities in the free troposphere, normalized to standard temperature and pressure, exceed number densities observed in boundary layer by a factor of 2 - 15. Typical number densities in the boundary layer were around 500 cm(-3). The large difference in particle number density between the boundary layer and the free troposphere agrees with previous observations of the in situ new particle production in the free troposphere. Analysis of the air mass history showed that even after more than a week of transport in the middle free troposphere, the newly formed ultrafine particles were more than one third of the total aerosol number concentration. Aerosol size distributions between 0.006 and 3 mum, divided into six vertical layers, show a C-shaped vertical structure with high concentrations of accumulation mode aerosols in the mixing layer and in the free troposphere above 10 km. The lower concentrations were observed in the free troposphere between 4 and 8 km. Enrichment in accumulation mode aerosol at altitudes above 10 km was attributed to outflow from deep convective clouds. | |||||
BibTeX:
@article{krejci_evolution_2003, author = {Krejci, R. and Strom, J. and de Reus, M. and Hoor, P. and Williams, J. and Fischer, H. and Hansson, H. C.}, title = {Evolution of aerosol properties over the rain forest in Surinam, South America, observed from aircraft during the LBA-CLAIRE 98 experiment}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D18}, url = {://WOS:000185477100001}, doi = {https://doi.org/10.1029/2001jd001375} } |
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Kreibich, H., Kern, J., de Camargo, P.B., Moreira, M.Z., Victoria, R.L. and Werner, D. | Estimation of symbiotic N-2 fixation in an Amazon floodplain forest | 2006 | Oecologia Vol. 147(2), pp. 359-368 |
article | DOI URL |
Abstract: Sustainable management for existing Amazonian forests requires an extensive knowledge about the limits of ecosystem nutrient cycles. Therefore, symbiotic nitrogen (N-2) fixation of legumes was investigated in a periodically flooded forest of the central Amazon floodplain (Varzea) over two hydrological cycles (20 months) using the N-15 natural abundance method. No seasonal variation in N-15 abundance (delta(15)N values) in trees which would suggest differences in N-2 fixation rates between the terrestrial and the aquatic phase was found. Estimations of the percentage of N derived from atmosphere (%Ndfa) for the nodulated legumes with Neptunia oleracea on the one side and Teramnus volubilis on the other resulted in mean %Ndfa values between 9 and 66%, respectively. More than half of the nodulated legume species had %Ndfa values above 45%. These relatively high N gains are important for the nodulated legumes during the whole hydrological cycle. With a %Ndfa of 4-5% for the entire Varzea forest, N-2 fixation is important for the ecosystem and therefore, has to be taken into consideration for new sustainable land-use strategies in this area. | |||||
BibTeX:
@article{kreibich_estimation_2006, author = {Kreibich, H. and Kern, J. and de Camargo, P. B. and Moreira, M. Z. and Victoria, R. L. and Werner, D.}, title = {Estimation of symbiotic N-2 fixation in an Amazon floodplain forest}, journal = {Oecologia}, year = {2006}, volume = {147}, number = {2}, pages = {359--368}, note = {Edition: 2005/12/06}, url = {://WOS:000235271600018}, doi = {https://doi.org/10.1007/s00442-005-0291-1} } |
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Kozovits, A.R., Bustamante, M.M.C., Garofalo, C.R., Bucci, S., Franco, A.C., Goldstein, G. and Meinzer, F.C. | Nutrient resorption and patterns of litter production and decomposition in a Neotropical Savanna | 2007 | Functional Ecology Vol. 21(6), pp. 1034-1043 |
article | DOI URL |
Abstract: 1. Deposition of nutrients due to anthropogenic activities has the potential to change nutrient availability in nutrient-limited ecosystems with consequences for plant and ecosystem processes. 2. Species-specific and ecosystem responses to the addition of nutrients were studied in a field experiment conducted in a Savanna (Cerrado sensu stricto) on dystrophic soil in central Brazil. Three fertilization treatments (N, P and N plus P additions) and unfertilized control were replicated in four 15 x 15 m plots per treatment. 3. Five of the dominant woody species were studied. Specific leaf area (SLA) was not affected by the treatments, but species responded differently in terms of foliar nutrient concentration, resorption efficiency and proficiency to the increased soil N and P availability. 4. Responses of N and P resorption suggested different levels of regulation for these two limiting elements, with a decrease in N and P resorption proficiency depending on the treatment. In general, under N fertilization, senesced leaves presented higher N concentration, whereas combined fertilization with N and P resulted in senesced leaves richer in P. The concomitant variation in P resorption efficiency and proficiency indicates a stronger regulation between them compared to N. 5. Results indicated a highly efficient and complete P resorption, while N concentrations in senesced leaves indicated intermediate or incomplete resorption efficiencies, supporting the idea that Cerrado plants might be more limited by P than by N. 6. At the ecosystem level, higher N concentration in the leaf litter was measured at the end of the dry season in the +NP-fertilized plots, resulting in a significantly faster decomposition rate in relation to the control treatment. Responses of litterfall and decomposition rates indicated that the system was generally more responsive to the combined addition of N and P than to fertilization with N or P alone over the relatively short time span of this study. | |||||
BibTeX:
@article{kozovits_nutrient_2007, author = {Kozovits, A. R. and Bustamante, M. M. C. and Garofalo, C. R. and Bucci, S. and Franco, A. C. and Goldstein, G. and Meinzer, F. C.}, title = {Nutrient resorption and patterns of litter production and decomposition in a Neotropical Savanna}, journal = {Functional Ecology}, year = {2007}, volume = {21}, number = {6}, pages = {1034--1043}, url = {://WOS:000250985100004}, doi = {https://doi.org/10.1111/j.1365-2435.2007.01325.x} } |
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Kourtchev, R.H.M., Connors, S., Levine, J.G., Archibald, A.T., Godoi, A.F.L., Paralovo, S.L., Barbosa, C.G.G., Souza, R.A.F., Manzi, A.O., Seco, R., Sjostedt, S., Park, J.-H., Guenther, A., Kim, S., Smith, J., Martin, S.T., Kalberer M., I. and Godoi | Molecular composition of organic aerosols in central Amazonia: an ultra-high-resolution mass spectrometry study [BibTeX] |
2016 | Atmospheric Chemistry and Physics Vol. 16, pp. 11899-11913 |
article | |
BibTeX:
@article{kourtchev_molecular_2016, author = {Kourtchev, Ricardo H. M. ; Connors, Sarah ; Levine, James G. ; Archibald, Alex T. ; Godoi, Ana F. L. ; Paralovo, Sarah L. ; Barbosa, Cybelli G. G. ; Souza, Rodrigo A. F. ; Manzi, Antonio O. ; Seco, Roger ; Sjostedt, Steve ; Park, Jeong-Hoo ; Guenther, Alex ; Kim, Saewung ; Smith, James ; Martin, Scot T. ; Kalberer, M., Ivan ; Godoi}, title = {Molecular composition of organic aerosols in central Amazonia: an ultra-high-resolution mass spectrometry study}, journal = {Atmospheric Chemistry and Physics}, year = {2016}, volume = {16}, pages = {11899--11913} } |
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Kosuth, P., Callede, J., Laraque, A., Filizola, N., Guyot, J.L., Seyler, P., Fritsch, J.M. and Guimaraes, V. | Sea-tide effects on flows in the lower reaches of the Amazon River | 2009 | Hydrological Processes Vol. 23(22), pp. 3141-3150 |
article | DOI URL |
Abstract: The physical influence of sea tides on the lower reaches of the Amazon River can be identified more than 1000 km upstream from the sea. Analysis of upstream tidal wave propagation on the Amazon River contributes to the understanding of the hydrodynamics of the lower reaches and to the quantification of the influence of sea level on sedimentation rates. Continuous over-the-year recording of water levels has been undertaken at eight locations along the lower reaches of the Amazon River and flow measurement campaigns have been organized for different river discharge rates (100000 m(3) s(-1), 190 000 m(3), s(-1) and 250 000 m(3) s(-1)) and sea-tide amplitudes (2-3.5 m). Damping, time-delay and deformation of the tidal wave signals, depending on water regimes and distances from the sea, have been analyzed. The physical processes of wave propagation and cyclic water storage and release have been investigated both through data analysis and the application of mathematical hydrodynamic models. The impact of tidal pulses on sediment transport to the sea has been assessed. Copyright (C) 2009 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{kosuth_sea-tide_2009, author = {Kosuth, Pascal and Callede, Jacques and Laraque, Alain and Filizola, Naziano and Guyot, Jean Loup and Seyler, Patrick and Fritsch, Jean Marie and Guimaraes, Valdemar}, title = {Sea-tide effects on flows in the lower reaches of the Amazon River}, journal = {Hydrological Processes}, year = {2009}, volume = {23}, number = {22}, pages = {3141--3150}, url = {://WOS:000271367800003}, doi = {https://doi.org/10.1002/hyp.7387} } |
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Koren, I., Remer, L.A. and Longo, K. | Reversal of trend of biomass burning in the Amazon | 2007 | Geophysical Research Letters Vol. 34(20) |
article | DOI URL |
Abstract: We use MODIS aerosol optical depth and AVHRR fire counts over the Amazon Basin to determine whether biomass burning is increasing or decreasing over continental scales in South America. We find a significant sustained increasing trend in both the seasonal mean optical depth and fire data that begins in the year 2000 and 1998, respectively, and continues through 2005. However, there is a sharp reversal of this trend in 2006 that causes the overall trend to become less significant. The sharp decrease of biomass burning in 2006 is linked to a tri-national policy shift first implemented in 2006. The results show how significantly human activity can affect the large scale environment. | |||||
BibTeX:
@article{koren_reversal_2007, author = {Koren, Ilan and Remer, Lorraine A. and Longo, Karla}, title = {Reversal of trend of biomass burning in the Amazon}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {20}, url = {://WOS:000250447100005}, doi = {https://doi.org/10.1029/2007gl031530} } |
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Koehler, P. and Huth, A. | Towards ground-truthing of spaceborne estimates of above-ground life biomass and leaf area index in tropical rain forests | 2010 | Biogeosciences Vol. 7(8), pp. 2531-2543 |
article | DOI URL |
Abstract: The canopy height h of forests is a key variable which can be obtained using air- or spaceborne remote sensing techniques such as radar interferometry or LIDAR. If new allometric relationships between canopy height and the biomass stored in the vegetation can be established this would offer the possibility for a global monitoring of the above-ground carbon content on land. In the absence of adequate field data we use simulation results of a tropical rain forest growth model to propose what degree of information might be generated from canopy height and thus to enable ground-truthing of potential future satellite observations. We here analyse the correlation between canopy height in a tropical rain forest with other structural characteristics, such as above-ground life biomass (AGB) (and thus carbon content of vegetation) and leaf area index (LAI) and identify how correlation and uncertainty vary for two different spatial scales. The process-based forest growth model FORMIND2.0 was applied to simulate (a) undisturbed forest growth and (b) a wide range of possible disturbance regimes typically for local tree logging conditions for a tropical rain forest site on Borneo (Sabah, Malaysia) in South-East Asia. In both undisturbed and disturbed forests AGB can be expressed as a power-law function of canopy height h (AGB = a center dot h(b)) with an r(2) similar to 60% if data are analysed in a spatial resolution of 20 m x 20 m (0.04 ha, also called plot size). The correlation coefficient of the regression is becoming significant better in the disturbed forest sites (r(2) = 91%) if data are analysed hectare wide. There seems to exist no functional dependency between LAI and canopy height, but there is also a linear correlation (r(2) similar to 60%) between AGB and the area fraction of gaps in which the canopy is highly disturbed. A reasonable agreement of our results with observations is obtained from a comparison of the simulations with permanent sampling plot (PSP) data from the same region and with the large-scale forest inventory in Lambir. We conclude that the spaceborne remote sensing techniques such as LIDAR and radar interferometry have the potential to quantify the carbon contained in the vegetation, although this calculation contains due to the heterogeneity of the forest landscape structural uncertainties which restrict future applications to spatial averages of about one hectare in size. The uncertainties in AGB for a given canopy height are here 20-40% (95% confidence level) corresponding to a standard deviation of less than +/- 10%. This uncertainty on the 1 ha-scale is much smaller than in the analysis of 0.04 ha-scale data. At this small scale (0.04 ha) AGB can only be calculated out of canopy height with an uncertainty which is at least of the magnitude of the signal itself due to the natural spatial heterogeneity of these forests. | |||||
BibTeX:
@article{koehler_towards_2010, author = {Koehler, P. and Huth, A.}, title = {Towards ground-truthing of spaceborne estimates of above-ground life biomass and leaf area index in tropical rain forests}, journal = {Biogeosciences}, year = {2010}, volume = {7}, number = {8}, pages = {2531--2543}, url = {://WOS:000281431800016}, doi = {https://doi.org/10.5194/bg-7-2531-2010} } |
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Kleidon, A., Malhi, Y. and Cox, P.M. | Maximum entropy production in environmental and ecological systems | 2010 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 365(1545), pp. 1297-1302 |
article | DOI URL |
Abstract: The coupled biosphere-atmosphere system entails a vast range of processes at different scales, from ecosystem exchange fluxes of energy, water and carbon to the processes that drive global biogeochemical cycles, atmospheric composition and, ultimately, the planetary energy balance. These processes are generally complex with numerous interactions and feedbacks, and they are irreversible in their nature, thereby producing entropy. The proposed principle of maximum entropy production (MEP), based on statistical mechanics and information theory, states that thermodynamic processes far from thermodynamic equilibrium will adapt to steady states at which they dissipate energy and produce entropy at the maximum possible rate. This issue focuses on the latest development of applications of MEP to the biosphere-atmosphere system including aspects of the atmospheric circulation, the role of clouds, hydrology, vegetation effects, ecosystem exchange of energy and mass, biogeochemical interactions and the Gaia hypothesis. The examples shown in this special issue demonstrate the potential of MEP to contribute to improved understanding and modelling of the biosphere and the wider Earth system, and also explore limitations and constraints to the application of the MEP principle. | |||||
BibTeX:
@article{kleidon_maximum_2010, author = {Kleidon, Axel and Malhi, Yadvinder and Cox, Peter M.}, title = {Maximum entropy production in environmental and ecological systems}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2010}, volume = {365}, number = {1545}, pages = {1297--1302}, note = {Edition: 2010/04/07}, url = {://WOS:000276272200001}, doi = {https://doi.org/10.1098/rstb.2010.0018} } |
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Kivalov, S.N. and Fitzjarrald, D.R. | Observing the Whole-Canopy Short-Term Dynamic Response to Natural Step Changes in Incident Light: Characteristics of Tropical and Temperate Forests [BibTeX] |
2019 | Boundary-Layer Meteorology Vol. 173(1), pp. 1-52 |
article | |
BibTeX:
@article{kivalov_observing_2019, author = {Kivalov, Sergey N. and Fitzjarrald, David R.}, title = {Observing the Whole-Canopy Short-Term Dynamic Response to Natural Step Changes in Incident Light: Characteristics of Tropical and Temperate Forests}, journal = {Boundary-Layer Meteorology}, year = {2019}, volume = {173}, number = {1}, pages = {1--52} } |
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Kivalov, S.N. and Fitzjarrald, D.R. | Quantifying and Modelling the Effect of Cloud Shadows on the Surface Irradiance at Tropical and Midlatitude Forests [BibTeX] |
2018 | Boundary-Layer Meteorology Vol. 166(2), pp. 165-198 |
article | DOI |
BibTeX:
@article{kivalov_quantifying_2018, author = {Kivalov, Sergey N. and Fitzjarrald, David R.}, title = {Quantifying and Modelling the Effect of Cloud Shadows on the Surface Irradiance at Tropical and Midlatitude Forests}, journal = {Boundary-Layer Meteorology}, year = {2018}, volume = {166}, number = {2}, pages = {165--198}, doi = {https://doi.org/10.1007/s10546-017-0301-y} } |
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Kisselle, K.W., Zepp, R.G., Burke, R.A., Pinto, A.D., Bustamante, M.M.C., Opsahl, S., Varella, R.F. and Viana, L.T. | Seasonal soil fluxes of carbon monoxide in burned and unburned Brazilian savannas | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Soil-atmosphere fluxes of carbon monoxide (CO) were measured from September 1999 through November 2000 in savanna areas in central Brazil (Cerrado) under different fire regimes using transparent and opaque static chambers. Studies focused on two vegetation types, cerrado stricto sensu (ss) (20-50% canopy cover) and campo sujo (open, scrubland), which were either burned every 2 years or protected from fire (for 26 years). CO emissions in transparent chambers varied seasonally, with highest fluxes during the late dry season and transition to wet season (August-October) and lowest fluxes late in the wet season (February-April). Daytime fluxes in the transparent chambers were always higher than in the opaque chambers. Similarly, a diurnal study showed negative fluxes for all nighttime measurements and positive measurements for all daytime measurements made with transparent chambers. Deposition velocities observed in the opaque chambers during the night fell in the 0.002-0.0014 cm s(-1) range, which is at the lower end of the range that has been observed in tropical, temperate, and high-latitude regions. No significant differences were found between the daytime annual average fluxes from unburned cerrado and unburned campo sujo (160 x 10(9) and 190 x 10(9) molecules cm(-2) s(-1), respectively). Fire increased soil surface CO emissions significantly in the burned cerrado plot. Measurements made 30 days after the fire showed daytime CO production over 10 times higher than that of the unburned cerrado ss (812.8 x 10(9) versus 76.8 x 10(9) molecules cm(-2) s(-1)). Postfire CO emissions were greater than prefire emissions for both opaque and transparent chambers. However, the fire-induced increase was greater in the transparent chambers. This suggests that the fire created both photochemically and thermally reactive precursors. Removal of litter and standing, dead plant material from plots in unburned campo sujo and a pasture was shown to dramatically decrease CO emissions. CO production in burned plots (using opaque chambers) was similar to previous measurements from Venezuelan and African savannas. | |||||
BibTeX:
@article{kisselle_seasonal_2002, author = {Kisselle, K. W. and Zepp, R. G. and Burke, R. A. and Pinto, A. D. and Bustamante, M. M. C. and Opsahl, S. and Varella, R. F. and Viana, L. T.}, title = {Seasonal soil fluxes of carbon monoxide in burned and unburned Brazilian savannas}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200008}, doi = {https://doi.org/10.1029/2001jd000638} } |
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Kirkman, G.A., Gut, A., Ammann, C., Gatti, L.V., Cordova, A.M., Moura, M.A.L., Andreae, M.O. and Meixner, F.X. | Surface exchange of nitric oxide, nitrogen dioxide, and ozone at a cattle pasture in Rondonia, Brazil | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Measurements of NO-NO(2)-O(3) trace gas exchange were performed for two transition season periods during the La Nina a year 1999 (30 April to 17 May, "wet-dry," and 24 September to 27 October, "dry-wet") over a cattle pasture in Rondonia. A dynamic chamber system (applied during the dry-wet season) was used to directly measure emission fluxes of nitric oxide (NO) and surface resistances for nitrogen dioxide (NO(2)) and ozone (O(3)) deposition. A companion study was simultaneously performed in an old-growth forest. In order to determine ecosystem-representative NO(2) and O(3) deposition fluxes for both measurement periods, an inferential method (multiresistance model) was applied to measure ambient NO(2) and O(3) concentrations using observed quantities of turbulent transport. Supplementary measurements included soil NO diffusivity and soil nutrient analysis. The observed NO soil emission fluxes were nine times lower than old-growth rain forest emissions under similar soil moisture and temperature conditions and were attributed to the combination of a reduced soil N cycle and lower effective soil NO diffusion at the pasture. Canopy resistances (R(c)) of both gases controlled the deposition processes during the day for both measurement periods. Day and night NO(2) canopy resistances were significantly similar (alpha = 0.05) during the dry-wet period. Ozone canopy resistances revealed significantly higher daytime resistances of 106 s m(-1) versus 65 s m(-1) at night because of plant, soil, and wet skin uptake processes, enhanced by stomatal activity at night and aqueous phase chemistry on vegetative and soil surfaces. The surface of the pasture was a net NO(x) sink during 1999, removing seven times more NO(2) from the atmosphere than was emitted as NO. | |||||
BibTeX:
@article{kirkman_surface_2002, author = {Kirkman, G. A. and Gut, A. and Ammann, C. and Gatti, L. V. and Cordova, A. M. and Moura, M. A. L. and Andreae, M. O. and Meixner, F. X.}, title = {Surface exchange of nitric oxide, nitrogen dioxide, and ozone at a cattle pasture in Rondonia, Brazil}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200057}, doi = {https://doi.org/10.1029/2001jd000523} } |
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Kirby, K.R., Laurance, W.F., Albernaz, A.K., Schroth, G., Fearnside, P.M., Bergen, S., Venticinque, E.M. and da Costa, C. | The future of deforestation in the Brazilian Amazon | 2006 | Futures Vol. 38(4), pp. 432-453 |
article | DOI URL |
Abstract: Concern about the future of Amazonian forests is growing as both the extent and rate of primary forest destruction increase. We combine spatial information on various biophysical, dernographic and infrastructural factors in the Brazilian Amazon with satellite data on deforestation to evaluate the relative importance of each factor to deforestation in the region. We assess the sensitivity of results to alternative sampling methodologies, and compare our results to those of previous empirical studies of Amazonian deforestation. Our findings, in concert with those of previous studies. send a clear message to planners: both paved and unpaved roads are key drivers of the deforestation process. Proximity to previous clearings, high population densities, low annual rainfall, and long dry seasons also increase the likelihood that a site will be deforested however, roads are consistently important and are the factors most amenable to policymaking. We argue that there is ample evidence to justify a fundamental change in current Amazonian development priorities if additional largescale losses of forests and environmental services are to be avoided. Published by Elsevier Ltd. | |||||
BibTeX:
@article{kirby_future_2006, author = {Kirby, K. R. and Laurance, W. F. and Albernaz, A. K. and Schroth, G. and Fearnside, P. M. and Bergen, S. and Venticinque, E. M. and da Costa, C.}, title = {The future of deforestation in the Brazilian Amazon}, journal = {Futures}, year = {2006}, volume = {38}, number = {4}, pages = {432--453}, url = {://WOS:000236337100004}, doi = {https://doi.org/10.1016/j.futures.2005.07.011} } |
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Kimes, D.S., Nelson, R.F., Salas, W.A. and Skole, D.L. | Mapping secondary tropical forest and forest age from SPOT HRV data | 1999 | International Journal of Remote Sensing Vol. 20(18), pp. 3625-3640 |
article | DOI URL |
Abstract: Accurate mapping of secondary forest and the age of these forests is critical to assess the carbon budget in tropical regions accurately. Using SPOT HRV (High Resolution Visible) data, techniques were developed and tested to discriminate primary forest, secondary forest and deforested areas on a study site in Rondonia, Brazil. Six co-registered SPOT HRV images (1986, 1988, 1989, 1991, 1992 and 1994) were used to create a time series of classified images of land cover (primary forest, secondary forest and deforested). These trajectories were used to identify secondary forest age classes relative to the most recent (1994) image. The resultant 1994 map of primary forest, secondary forest age classes and deforested areas served as ground reference data to establish training and testing sites. Several band 2 and 3 texture measurements were calculated using a 3 x 3 window to quantify canopy homogeneity. Neural networks and linear analysis techniques were tested for discriminating between primary forest, secondary forest and deforested pixels. The techniques were also employed to extract secondary forest age. A neural network using band 3 and a texture measure of band 2 and 3 from a single image (1994) discriminated primary forest, secondary forest (1 to textgreater9 years) and deforested pixel with an average accuracy of 95%. The use of texture information increased the secondary forest discrimination accuracy 6.4% (from 83.5 to 89.9%). Spectral and textural information were also used to predict secondary forest age as a continuous variable. The neural network with the highest accuracy produced a RMSE (predicted network age versus actual secondary forest age) of 2.0 years with a coefficient of determination (predicted versus true) of 0.38. These results were significantly improved by using multitemporal information. The spectral and textural information from two images (1994 and 1989) were used to extract secondary forest information. The neural network results showed that 95.5% of the secondary forest pixels were correctly classified as secondary forest pixels (as opposed to 89.9% of the pixels using only the 1994 image). The RMSE and R-2 accuracies in extracting secondary forest age as a continuous variable were 1.3 and 0.75, respectively. | |||||
BibTeX:
@article{kimes_mapping_1999, author = {Kimes, D. S. and Nelson, R. F. and Salas, W. A. and Skole, D. L.}, title = {Mapping secondary tropical forest and forest age from SPOT HRV data}, journal = {International Journal of Remote Sensing}, year = {1999}, volume = {20}, number = {18}, pages = {3625--3640}, url = {://WOS:000083481800014}, doi = {https://doi.org/10.1080/014311699211246} } |
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Kim, Y., Knox, R.G., Longo, M., Medvigy, D., Hutyra, L.R., Pyle, E.H., Wofsy, S.C., Bras, R.L. and Moorcroft, P.R. | Seasonal carbon dynamics and water fluxes in an Amazon rainforest | 2012 | Global Change Biology Vol. 18(4), pp. 1322-1334 |
article | DOI URL |
Abstract: Satellite-based observations indicate that seasonal patterns in canopy greenness and productivity in the Amazon are negatively correlated with precipitation, with increased greenness occurring during the dry months. Flux tower measurements indicate that the canopy greening that occurs during the dry season is associated with increases in net ecosystem productivity (NEP) and evapotranspiration (ET). Land surface and terrestrial biosphere model simulations for the region have predicted the opposite of these observed patterns, with significant declines in greenness, NEP, and ET during the dry season. In this study, we address this issue mainly by developing an empirically constrained, light-controlled phenology submodel within the Ecosystem Demography model version 2 (ED2). The constrained ED2 model with a suite of field observations shows markedly improved predictions of seasonal ecosystem dynamics, more accurately capturing the observed patterns of seasonality in water, carbon, and litter fluxes seen at the Tapajos National Forest, Brazil (2.86 degrees S, 54.96 degrees W). Long-term simulations indicate that this light-controlled phenology increases the resilience of Amazon forest NEP to interannual variability in climate forcing. | |||||
BibTeX:
@article{kim_seasonal_2012, author = {Kim, Yeonjoo and Knox, Ryan G. and Longo, Marcos and Medvigy, David and Hutyra, Lucy R. and Pyle, Elizabeth H. and Wofsy, Steven C. and Bras, Rafael L. and Moorcroft, Paul R.}, title = {Seasonal carbon dynamics and water fluxes in an Amazon rainforest}, journal = {Global Change Biology}, year = {2012}, volume = {18}, number = {4}, pages = {1322--1334}, url = {://WOS:000301533100010}, doi = {https://doi.org/10.1111/j.1365-2486.2011.02629.x} } |
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Killeen, T.J. and Solorzano, L.A. | Conservation strategies to mitigate impacts from climate change in Amazonia | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1881-1888 |
article | DOI URL |
Abstract: Protected area systems and conservation corridors can help mitigate the impacts of climate change on Amazonian biodiversity. We propose conservation design criteria that will help species survive in situ or adjust range distributions in response to increased drought. The first priority is to protect the western Amazon, identified as the 'Core Amazon', due to stable rainfall regimes and macro-ecological phenomena that have led to the evolution of high levels of biodiversity. Ecotones can buffer the impact from climate change because populations are genetically adapted to climate extremes, particularly seasonality, because high levels of habitat diversity are associated with edaphic variability. Future climatic tension zones should be surveyed for geomorphological features that capture rain or conserve soil moisture to identify potential refugia for humid forest species. Conservation corridors should span environmental gradients to ensure that species can shift range distributions. Riparian corridors provide protection to both terrestrial and aquatic ecosystems. Multiple potential altitudinal corridors exist in the Andes, but natural and anthropogenic bottlenecks will constrain the ability of species to shift their ranges and adapt to climate change. Planned infrastructure investments are a serious threat to the potential to consolidate corridors over the short and medium term. | |||||
BibTeX:
@article{killeen_conservation_2008, author = {Killeen, Timothy J. and Solorzano, Luis A.}, title = {Conservation strategies to mitigate impacts from climate change in Amazonia}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1881--1888}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500021}, doi = {https://doi.org/10.1098/rstb.2007.0018} } |
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Khanna, J., Medvigy, D., Fueglistaler, S. and Walko, R. | Regional dry-season climate changes due to three decades of Amazonian deforestation [BibTeX] |
2017 | Nature Climate Change (Letters) | article | DOI |
BibTeX:
@article{khanna_regional_2017, author = {Khanna, Jaya and Medvigy, David and Fueglistaler, Stephan and Walko, Robert}, title = {Regional dry-season climate changes due to three decades of Amazonian deforestation}, journal = {Nature Climate Change (Letters)}, year = {2017}, doi = {https://doi.org/10.1038/NCLIMATE3226} } |
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Khanna, J., Medvigy, D., Fisch, G., Araújo, T.T.d. and Neves, T. | Regional Hydroclimatic Variability Due To Contemporary Deforestation in Southern Amazonia and Associated Boundary Layer Characteristics [BibTeX] |
2018 | Journal of Geophysical Research: Atmospheres Vol. 123(3993-4014) |
article | DOI |
BibTeX:
@article{khanna_regional_2018, author = {Khanna, Jaya and Medvigy, David and Fisch, Gilberto and Araújo, Theomar Trindade de and Neves, Tiburtino}, title = {Regional Hydroclimatic Variability Due To Contemporary Deforestation in Southern Amazonia and Associated Boundary Layer Characteristics}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2018}, volume = {123}, number = {3993-4014}, doi = {https://doi.org/10.1002/2017JD027888} } |
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Kesselmeier, J., Kuhn, U., Wolf, A., Andreae, M.O., Ciccioli, P., Brancaleoni, E., Frattoni, M., Guenther, A., Greenberg, J., Vasconcellos, P.D., de Oliva, T., Tavares, T. and Artaxo, P. | Atmospheric volatile organic compounds (VOC) at a remote tropical forest site in central Amazonia | 2000 | Atmospheric Environment Vol. 34(24), pp. 4063-4072 |
article | DOI URL |
Abstract: According to recent assessments, tropical woodlands contribute about half of all global natural non-methane volatile organic compound (VOC) emissions. Large uncertainties exist especially about fluxes of compounds other than isoprene and monoterpenes. During the Large-Scale Biosphere/Atmosphere Experiment in Amazonia - Cooperative LBA Airborne Regional Experiment 1998 (LBA-CLAIRE-98) campaign, we measured the atmospheric mixing ratios of different species of VOC at a ground station at Balbina, Amazonia, The station was located 100 km north of Manaus, SE of the Balbina reservoir, with 200-1000 km of pristine forest in the prevailing wind directions. Sampling methods included DNPH-coated cartridges for carbonyls and cartridges filled with graphitic carbons of different surface characteristics for other VOCs. The most prominent VOC species present in air were formaldehyde and isoprene, each up to several ppb. Concentrations of methylvinyl ketone as well as methacroleine, both oxidation products of isoprene, were relatively low, indicating a very low oxidation capacity in the lower atmospheric boundary layer, which is in agreement with a daily ozone maximum of textless 20 ppb. Total monoterpene concentration was below 1 ppb, We detected only very low amounts of VOC species, such as benzene, deriving exclusively from anthropogenic sources. (C) 2000 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{kesselmeier_atmospheric_2000, author = {Kesselmeier, J. and Kuhn, U. and Wolf, A. and Andreae, M. O. and Ciccioli, P. and Brancaleoni, E. and Frattoni, M. and Guenther, A. and Greenberg, J. and Vasconcellos, P. D. and de Oliva, T. and Tavares, T. and Artaxo, P.}, title = {Atmospheric volatile organic compounds (VOC) at a remote tropical forest site in central Amazonia}, journal = {Atmospheric Environment}, year = {2000}, volume = {34}, number = {24}, pages = {4063--4072}, url = {://WOS:000088818200002}, doi = {https://doi.org/10.1016/s1352-2310(00)00186-2} } |
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Kesselmeier, J., Kuhn, U., Rottenberger, S., Biesenthal, T., Wolf, A., Schebeske, G., Andreae, M.O., Ciccioli, P., Brancaleoni, E., Frattoni, M., Oliva, S.T., Botelho, M.L., Silva, C.M.A. and Tavares, T.M. | Concentrations and species composition of atmospheric volatile organic compounds (VOCs) as observed during the wet and dry season in Rondonia (Amazonia) | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: We measured atmospheric gas-phase volatile organic compounds (VOCs) at the end of the wet and end of the dry season at a tropical rainforest site in Rondonia, Brazil, using various sampling techniques such as trapping on different adsorbents or cryogenic trapping combined with appropriate analysis techniques. The measuring sites were located inside the forest of a biological reserve near Ji-Parana. Sampling was performed from 3 May 1999 to 17 May 1999 and from 24 September 1999 to 2 November 1999 during the "wet-to-dry season transition'' and "dry-to-wet season transition'' periods in Rondonia, respectively. Samples were obtained at the canopy top close to the potential sources/sinks for these compounds as well as above the forest. We report the measured concentrations of a large number of different VOCs and their oxidation products, such as isoprenoids, organic acids, carbonyls, aromatics, and alcohols. The most prominent VOCs present in air over the last part of the wet season were isoprene, formaldehyde, and formic acid, with mixing ratios of each ranging up to several parts per billion (ppb). Methyl vinyl ketone as well as methacrolein, both oxidation products of isoprene, ranged around 1 ppb. The sum of the measured monoterpene concentrations was below 1 ppb. At the end of the dry season, the amount of C-1-C-2 organic acids and C-1-C-2 aldehydes increased significantly up to 17 and 25 ppb, respectively, which is thought to result significantly from vegetation fire emissions. High methanol concentrations also support this scenario. At the same time, however, atmospheric mixing ratios of biogenic compounds such as isoprene increased up to 30 ppb near the crown region and well above 10 ppb at 10-20 m over the forest, whereas monoterpene species seem to decrease. We discuss seasonal development of the vegetation and climatological factors to be responsible for such concentration pattern. The results give an impression about the variability and concentration of VOCs during the different seasons. | |||||
BibTeX:
@article{kesselmeier_concentrations_2002, author = {Kesselmeier, J. and Kuhn, U. and Rottenberger, S. and Biesenthal, T. and Wolf, A. and Schebeske, G. and Andreae, M. O. and Ciccioli, P. and Brancaleoni, E. and Frattoni, M. and Oliva, S. T. and Botelho, M. L. and Silva, C. M. A. and Tavares, T. M.}, title = {Concentrations and species composition of atmospheric volatile organic compounds (VOCs) as observed during the wet and dry season in Rondonia (Amazonia)}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200010}, doi = {https://doi.org/10.1029/2000jd000267} } |
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Kesselmeier, J., Gunther, A., Hoffmann, T., Piedade, M.T. and Warnke, J. | Natural Volatile Organic Compound Emissions From Plants and Their Roles in Oxidant Balance and Particle Formation [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 183-206 |
incollection | |
BibTeX:
@incollection{m_keller_natural_2009, author = {Kesselmeier, Jürgen and Gunther, Alex and Hoffmann, Thorsten and Piedade, Maria Teresa and Warnke, Jörg}, title = {Natural Volatile Organic Compound Emissions From Plants and Their Roles in Oxidant Balance and Particle Formation}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {183--206} } |
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Kesselmeier, J., Ciccioli, P., Kuhn, U., Stefani, P., Biesenthal, T., Rottenberger, S., Wolf, A., Vitullo, M., Valentini, R., Nobre, A., Kabat, P. and Andreae, M.O. | Volatile organic compound emissions in relation to plant carbon fixation and the terrestrial carbon budget | 2002 | Global Biogeochemical Cycles Vol. 16(4) |
article | DOI URL |
Abstract: [1] A substantial amount of carbon is emitted by terrestrial vegetation as biogenic volatile organic compounds (VOC), which contributes to the oxidative capacity of the atmosphere, to particle production and to the carbon cycle. With regard to the carbon budget of the terrestrial biosphere, a release of these carbon compounds is regarded as a loss of photosynthetically fixed carbon. The significance of this loss for the regional and global carbon cycles is controversial. We estimate the amount of VOC carbon emitted in relation to the CO2 taken up, based on our own enclosure and micrometeorological flux measurements of VOC emissions and CO2 exchange within the Mediterranean area and the tropical rainforest in Amazonia and on literature data. While VOC flux estimates are small in relation to net primary productivity and gross primary productivity, the amount of carbon lost as VOC emissions can be highly significant relative to net ecosystem productivity. In fact, VOC losses are of the same order of magnitude as net biome productivity. Although we must assume that large amounts of these reemissions are recycled within the biosphere, a substantial part can be assumed to be lost into longer-lived oxidation products that are lost from the terrestrial biosphere by transport. However, our current knowledge does not allow a reliable estimation of this carbon loss. | |||||
BibTeX:
@article{kesselmeier_volatile_2002, author = {Kesselmeier, J. and Ciccioli, P. and Kuhn, U. and Stefani, P. and Biesenthal, T. and Rottenberger, S. and Wolf, A. and Vitullo, M. and Valentini, R. and Nobre, A. and Kabat, P. and Andreae, M. O.}, title = {Volatile organic compound emissions in relation to plant carbon fixation and the terrestrial carbon budget}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {4}, url = {://WOS:000181107200001}, doi = {https://doi.org/10.1029/2001gb001813} } |
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Kemenes, A., Forsberg, B.R. and Melack, J.M. | Downstream emissions of CH4 and CO2 from hydroelectric reservoirs (Tucuruí, Samuel, and Curuá-Una) in the Amazon basin [BibTeX] |
2016 | Inland Waters Vol. 6, pp. 295-302 |
article | DOI |
BibTeX:
@article{kemenes_downstream_2016, author = {Kemenes, Alexandre and Forsberg, Bruce R. and Melack, John M.}, title = {Downstream emissions of CH4 and CO2 from hydroelectric reservoirs (Tucuruí, Samuel, and Curuá-Una) in the Amazon basin}, journal = {Inland Waters}, year = {2016}, volume = {6}, pages = {295--302}, doi = {https://doi.org/10.5268/IW-6.3.980} } |
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Kemenes, A., Forsberg, B.R. and Melack, J.M. | CO(2) emissions from a tropical hydroelectric reservoir (Balbina, Brazil) | 2011 | Journal of Geophysical Research-Biogeosciences Vol. 116(G3) |
article | DOI URL |
Abstract: Hydroelectric reservoirs can release significant quantities of CO(2), but very few results are available from the tropics. The objective of the present study was to estimate the emission of CO(2) from the Balbina hydroelectric reservoir in the central Brazilian Amazon. Diffusive and ebullitive emissions were estimated at regular intervals, both above and below the dam, using a combination of static chambers and submerged funnels. Gas releases immediately below the dam were calculated as the difference between gas flux at the entrance and the outflow of the hydroelectric turbines. An inundation model derived from a bathymetric map and daily stage readings was used for spatial and temporal interpolation of reservoir emissions. Annual emissions of CO(2), upstream and downstream of Balbina dam for 2005, were estimated as 2450 and 81 Gg C, respectively, for a total annual flux of 2531 Gg C. Upstream emissions were predominantly diffusive with only 0.02 Gg C yr(-1) resulting from ebullition. On average, 51% of the downstream emission was released by degassing at the turbine outflow, and the remainder was lost by diffusion from the downstream river. The total annual greenhouse gas emission from Balbina dam, including the CO(2) equivalent of previously estimated CH(4) emissions, was 3 Tg C yr(-1), equivalent to approximately 50% of the CO(2) emissions derived from the burning of fossil fuels in the Brazilian metropolis of Sao Paulo. | |||||
BibTeX:
@article{kemenes_co2_2011, author = {Kemenes, Alexandre and Forsberg, Bruce R. and Melack, John M.}, title = {CO(2) emissions from a tropical hydroelectric reservoir (Balbina, Brazil)}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2011}, volume = {116}, number = {G3}, url = {://WOS:000293086600001 http://www.agu.org/pubs/crossref/2011/2010JG001465.shtml}, doi = {https://doi.org/10.1029/2010jg001465} } |
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Kemenes, A., Forsberg, B.R. and Melack, J.M. | Methane release below a tropical hydroelectric dam | 2007 | Geophysical Research Letters Vol. 34(12) |
article | DOI URL |
Abstract: Tropical reservoirs upstream from hydroelectric dams are known to release significant amounts of methane to the atmosphere. Here we demonstrate that methane emissions downstream from hydroelectric dams can also be large. Emissions of CH(4) downstream of Balbina reservoir in the central Amazon basin (Brazil) were calculated from regular measurements of degassing in the outflow of the turbines and downstream diffusive losses. Annual emissions from the reservoir surface and downstream from the dam were 34 and 39 Gg C, respectively. The downstream emission alone represented the equivalent of 3% of all methane released from central Amazon floodplain. | |||||
BibTeX:
@article{kemenes_methane_2007, author = {Kemenes, Alexandre and Forsberg, Bruce Rider and Melack, John Michael}, title = {Methane release below a tropical hydroelectric dam}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {12}, url = {://WOS:000247533400002}, doi = {https://doi.org/10.1029/2007gl029479} } |
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Keller, M., Varner, R.K., Dias, J., Silva, H., Crill, P. and de Oliveira Jr., R. | Soil-atmosphere exchange of nitrous oxide, nitric oxide, methane, and carbon dioxide in logged and undisturbed forest in the Tapajos National Forest, Brazil | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Selective logging is an extensive land use in the Brazilian Amazon region. The soil - atmosphere fluxes of nitrous oxide (N(2)O), nitric oxide (NO), methane (CH(4)), and carbon dioxide (CO(2)) are studied on two soil types ( clay Oxisol and sandy loam Ultisol) over two years ( 2000 - 01) in both undisturbed forest and forest recently logged using reduced impact forest management in the Tapajos National Forest, near Santarem, Para, Brazil. In undisturbed forest, annual soil - atmosphere fluxes of N(2)O (mean +/- standard error) were 7.9 +/- 0.7 and 7.0 +/- 0.6 ng N cm(-2) h(-1) for the Oxisol and 1.7 +/- 0.1 and 1.6 +/- 0.3 ng N cm(-2) h(-1) for the Ultisol for 2000 and 2001, respectively. The annual fluxes of NO from undisturbed forest soil in 2001 were 9.0 +/- 2.8 ng N cm(-2) h(-1) for the Oxisol and 8.8 +/- 5.0 ng N cm(-2) h(-1) for the Ultisol. Consumption of CH4 from the atmosphere dominated over production on undisturbed forest soils. Fluxes averaged - 0.3 +/- 0.2 and - 0.1 +/- 0.9 mg CH(4) m(-2) day(-1) on the Oxisol and - 1.0 +/- 0.2 and - 0.9 +/- 0.3 mg CH(4) m(-2) day(-1) on the Ultisol for years 2000 and 2001. For CO(2) in 2001, the annual fluxes averaged 3.6 +/- 0.4 mu mol m(-2) s(-1) on the Oxisol and 4.9 +/- 1.1 mu mol m(-2) s(-1) on the Ultisol. We measured fluxes over one year each from two recently logged forests on the Oxisol in 2000 and on the Ultisol in 2001. Sampling in logged areas was stratified from greatest to least ground disturbance covering log decks, skid trails, tree-fall gaps, and forest matrix. Areas of strong soil compaction, especially the skid trails and logging decks, were prone to significantly greater emissions of N(2)O, NO, and especially CH(4). In the case of CH(4), estimated annual emissions from decks reached extremely high rates of 531 +/- 419 and 98 +/- 41 mg CH(4) m(-2) day(-1), for Oxisol and Ultisol sites, respectively, comparable to wetland emissions in the region. We calculated excess fluxes from logged areas by subtraction of a background forest matrix or undisturbed forest flux and adjusted these fluxes for the proportional area of ground disturbance. Our calculations suggest that selective logging increases emissions of N(2)O and NO from 30% to 350% depending upon conditions. While undisturbed forest was a CH(4) sink, logged forest tended to emit methane at moderate rates. Soil - atmosphere CO(2) fluxes were only slightly affected by logging. The regional effects of logging cannot be simply extrapolated based upon one site. We studied sites where reduced impact harvest management was used while in typical conventional logging ground damage is twice as great. Even so, our results indicate that for N(2)O, NO, and CH(4), logging disturbance may be as important for regional budgets of these gases as other extensive land-use changes in the Amazon such as the conversion of forest to cattle pasture. | |||||
BibTeX:
@article{keller_soil-atmosphere_2005, author = {Keller, M. and Varner, R. K. and Dias, J.D. and Silva, H. and Crill, P. and de Oliveira Jr., R.C.}, title = {Soil-atmosphere exchange of nitrous oxide, nitric oxide, methane, and carbon dioxide in logged and undisturbed forest in the Tapajos National Forest, Brazil}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241358000001} } |
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Keller, M., Silva-Dias, M.A., Nepstad, D.C. and Andreae, M.O. | The large-scale biosphere-atmosphere experiment in Amazonia: Analyzing regional land use change effects | 2004 | Vol. 153Ecosystems and Land Use Change, pp. 321-334 |
incollection | DOI URL |
Abstract: Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multi-disciplinary, multinational scientific project led by Brazil. LBA researchers seek to understand Amazonia in its global context especially with regard to regional and global climate. Current development activities in Amazonia including deforestation, logging, cattle ranching, and agriculture significantly perturb regional and global carbon budgets and the atmospheric radiation budget through both greenhouse gas inputs and the increase in atmospheric particulates generated by fires. The Brazilian Amazon currently releases about 0.2 Pg-C to the atmosphere each year as a result of net deforestation. Logging and forest fire activity are poorly quantified but certainly increase this amount by more than 10%. Fires associated with land management activities generate smoke that leads to heating of the lower atmosphere, decreases in overall cloudiness, increases in cloud lifetimes, and the suppression of rainfall. There are considerable uncertainties associated with our understanding of smoke effects. Present development trends point to agricultural intensification in the Brazilian Amazon. This intensification and the associated generation of wealth present an opportunity to enhance governance on the frontier and to minimize the damaging effects of fires. | |||||
BibTeX:
@incollection{defries_large-scale_2004, author = {Keller, M. and Silva-Dias, M. A. and Nepstad, D. C. and Andreae, M. O.}, title = {The large-scale biosphere-atmosphere experiment in Amazonia: Analyzing regional land use change effects}, booktitle = {Ecosystems and Land Use Change}, year = {2004}, volume = {153}, pages = {321--334}, url = {://WOS:000226789500023}, doi = {https://doi.org/10.1029/153gm24} } |
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Keller, M., Palace, M. and Hurtt, G. | Biomass estimation in the Tapajos National Forest, Brazil - Examination of sampling and allometric uncertainties | 2001 | Forest Ecology and Management Vol. 154(3), pp. 371-382 |
article | DOI URL |
Abstract: changes in the biomass of Amazon region forests represent an important component of the global carbon cycle but the biomass of these forests remains poorly quantified. Minimizing the error in forest biomass estimates is necessary in order to reduce the uncertainty in future Amazon carbon budgets. We examined forest survey data for trees with a diameter at breast height (DBH) greater than 35 cm from four plots with a total area of 392 ha in the Tapajos National Forest near Santarem, Para, Brazil (3 degrees 04'S, 54 degrees 95'W). The average frequency of trees greater than 35 cm DBH was approximately 55 ha(-1). Based on tree diameters, allometric relations, and published relations for biomass in other compartments besides trees of DBH textgreater 35 cm., we estimated a total biomass density of 372 Mg ha(-1). We produced a highly conservative error estimate of about 50% of this value. Trees with diameters greater than 35 cm DBH accounted for about half of the total biomass. This estimate includes all live and dead plant material above- and below-ground with the exception of soil organic matter. We propagated errors in sampling and those associated with allometric relations and other ratios used to estimate biomass of roots, lianas and epiphytes, and necromass. The major sources of uncertainty in our estimate were found in the allometric relations for trees with DBH greater than 35 cm, in the estimates of biomass of trees with DBH less than 35 cm., and in root biomass. Simulated sampling based on our full survey, suggests that we could have estimated mean biomass per hectare for trees (DBH greater than or equal to 35 cm) to within 20% (sampling error only) with 95% confidence by sampling 21 randomly selected 0.25 ha plots in our study area. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{keller_biomass_2001, author = {Keller, M. and Palace, M. and Hurtt, G.}, title = {Biomass estimation in the Tapajos National Forest, Brazil - Examination of sampling and allometric uncertainties}, journal = {Forest Ecology and Management}, year = {2001}, volume = {154}, number = {3}, pages = {371--382}, url = {://WOS:000172287600003}, doi = {https://doi.org/10.1016/s0378-1127(01)00509-6} } |
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Keller, M., Palace, M., Asner, G.P., Pereira, R. and Silva, J.N.M. | Coarse woody debris in undisturbed and logged forests in the eastern Brazilian Amazon | 2004 | Global Change Biology Vol. 10(5), pp. 784-795 |
article | DOI URL |
Abstract: Coarse woody debris (CWD) is an important component of the carbon cycle in tropical forests. We measured the volume and density of fallen CWD at two sites, Cauaxi and Tapajos in the Eastern Amazon. At both sites we studied undisturbed forests (UFs) and logged forests 1 year after harvest. Conventional logging (CL) and reduced impact logging (RIL) were used for management on areas where the geometric volumes of logs harvested was about 25-30 m(3) ha(-1). Density for five classes of fallen CWD for large material (textgreater10 cm diameter) ranged from 0.71 to 0.28 Mg m(-3) depending upon the degree of decomposition. Density of wood within large fallen logs varied with position relative to the ground and with distance from the center of the log. Densities for materials with diameters from 2 to 5 and 5 to 10 cm were 0.36 and 0.45 Mg m(-3), respectively. The average mass (+/-SE) of fallen CWD at Cauaxi was 55.2 (4.7), 74.7 (0.6), and 107.8 (10.5) Mg ha(-1) for duplicate UF, RIL, and CL sites, respectively. At Tapajos, the average mass of fallen CWD was 50.7 (1.1) Mg ha(-1) for UF and 76.2 (10.2) Mg ha(-1) for RIL for duplicate sites compared with 282 Mg ha(-1) for live aboveground biomass. Small- and medium-sized material (textless10 cm dia.) accounted for 8-18% of the total fallen CWD mass. The large amount of fallen CWD at these UF sites relative to standing aboveground biomass suggests either that the forests have recently been subjected to a pulse of high mortality or that they normally suffer a high mortality rate in the range of 0.03 per year. Accounting for background CWD in UF, CL management produced 2.7 times as much CWD as RIL management. Excess CWD at logging sites would generate a substantial CO2 emission given the high rates of decay in moist tropical forests. | |||||
BibTeX:
@article{keller_coarse_2004, author = {Keller, M. and Palace, M. and Asner, G. P. and Pereira, R. and Silva, J. N. M.}, title = {Coarse woody debris in undisturbed and logged forests in the eastern Brazilian Amazon}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {784--795}, url = {://WOS:000221421600018 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00770.x/asset/j.1529-8817.2003.00770.x.pdf?v=1&t=h6hwxenf&s=73a401ba5ac3cbfafb8cb004a2601fd4f696b000}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00770.x} } |
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Keller, M., Bustamante, M., Gash, J. and Silva Dias, P. | Amazonia and Global Change [BibTeX] |
2009 | Vol. vol. 186 |
book | DOI URL |
BibTeX:
@book{aguiar_amazonia_2009, author = {Keller, M. and Bustamante, M. and Gash, J. and Silva Dias, P.}, title = {Amazonia and Global Change}, year = {2009}, volume = {vol. 186}, note = {Section: 565 pp.}, url = {http://onlinelibrary.wiley.com/book/10.1029/GM186}, doi = {https://doi.org/10.1029/GM186} } |
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Keller, M., Asner, G.P., Blate, G., McGlocklin, J., Merry, F., Pena-Claros, M. and Zweede, J. | Timber production in selectively logged tropical forests in South America | 2007 | Frontiers in Ecology and the Environment Vol. 5(4), pp. 213-216 |
article | DOI URL |
Abstract: Selective logging is an extensive land-use practice in South America. Governments in the region have enacted policies to promote the establishment and maintenance of economically productive and sustainable forest industries. However, both biological and policy constraints threaten to limit the viability of the industry over the long term. Biological constraints, such as slow tree growth rates, can be overcome somewhat by management practices. In order to improve the likelihood of success for sustainable management, it is important to accept that forests change over time and that managed forests may be different than those of the present. Furthermore, education campaigns must convince decision makers and the public of the value of forest resources. We recommend that the forest sector be governed by simple, understandable regulations, based on sound science and consistent enforcement, and that governments work with, instead of against, industry. Problems of tropical forest management are far from being solved, so biological and social scientists should continue to generate new knowledge to promote effective management. | |||||
BibTeX:
@article{keller_timber_2007, author = {Keller, Michael and Asner, Gregory P. and Blate, Geoffrey and McGlocklin, John and Merry, Frank and Pena-Claros, Marielos and Zweede, Johan}, title = {Timber production in selectively logged tropical forests in South America}, journal = {Frontiers in Ecology and the Environment}, year = {2007}, volume = {5}, number = {4}, pages = {213--216}, url = {://WOS:000246414500007}, doi = {https://doi.org/10.1890/1540-9295(2007)5%5B213:tpislt%5D2.0.co;2} } |
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Keller, M., Alencar, A., Asner, G.P., Braswell, B., Bustamante, M., Davidson, E., Feldpausch, T., Fernandes, E., Goulden, M., Kabat, P., Kruijt, B., Luizao, F., Miller, S., Markewitz, D., Nobre, A.D., Nobre, C.A., Priante, N., da Rocha, H., Dias, P.S., von Randow, C. and Vourlitis, G.L. | Ecological research in the large-scale biosphere-atmosphere experiment in Amazonia: Early results | 2004 | Ecological Applications Vol. 14(4), pp. S3-S16 |
article | URL |
Abstract: The Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multinational, interdisciplinary research program led by Brazil. Ecological studies in LBA focus on how tropical forest conversion, regrowth, and selective logging influence carbon storage,. nutrient dynamics, trace gas fluxes, and the prospect for sustainable land use in the Amazon region. Early results from ecological studies within LBA emphasize the variability within the vast Amazon region and the profound effects that land-use and landcover changes are having on that landscape. The predominant land cover of the Amazon region is evergreen forest; nonetheless, LBA studies have observed strong seasonal patterns in gross primary production, ecosystem respiration, and net ecosystem exchange, as well as phenology and tree growth. The seasonal patterns vary spatially and interannually and evidence suggests that these patterns are driven not only by variations in weather but also by innate biological rhythms of the forest species. Rapid rates of deforestation have marked the forests of the Amazon region over the past three decades. Evidence from ground-based surveys and remote sensing show that substantial areas of forest are being degraded by logging activities and through the collapse of forest edges. Because forest edges and logged forests are susceptible to fire, positive feedback cycles of forest degradation may be initiated by land-use-change events. LBA studies indicate that cleared lands in the Amazon, once released from cultivation or pasture usage, regenerate biomass rapidly. However, the pace of biomass accumulation is dependent upon past land use and the depletion of nutrients by unsustainable land-management practices. The challenge for ongoing research within LBA is to integrate the recognition of diverse patterns and processes into general models for prediction of regional ecosystem function. | |||||
BibTeX:
@article{keller_ecological_2004, author = {Keller, M. and Alencar, A. and Asner, G. P. and Braswell, B. and Bustamante, M. and Davidson, E. and Feldpausch, T. and Fernandes, E. and Goulden, M. and Kabat, P. and Kruijt, B. and Luizao, F. and Miller, S. and Markewitz, D. and Nobre, A. D. and Nobre, C. A. and Priante, N. and da Rocha, H. and Dias, P. S. and von Randow, C. and Vourlitis, G. L.}, title = {Ecological research in the large-scale biosphere-atmosphere experiment in Amazonia: Early results}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S3--S16}, url = {://WOS:000223269000002} } |
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Keeling, H.C. and Phillips, O.L. | A calibration method for the crown illumination index for assessing forest light environments | 2007 | Forest Ecology and Management Vol. 242(2-3), pp. 431-437 |
article | DOI URL |
Abstract: The crown illumination index (CII) is an ordinal scale frequently used to qualitatively assess the light environment within a forest. Although this method provides a simple and rapid approach, it can be subjective and needs to be calibrated against quantitative measurements of canopy structure. A study was undertaken in north-western Amazonia to provide a means to calibrate the CII in tropical forests. Hemispherical photographs were taken to represent each CII class, which were then analysed using HemiView 2.1 software in order to calculate light availability factors. The proportion of visible sky and indirect, direct and global site factors (the proportion of indirect, direct and total radiation reaching a point, compared to an open location) were all found to correlate strongly with CII class and therefore offer a viable method for calibration. CII classes could only be weakly defined with respect to leaf area index (LAI), however, and so conversion of CII to LAI or vice versa is problematic. The results of this study provide a quantified description of each index class, significantly improving interpretation of the crown illumination index. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{keeling_calibration_2007, author = {Keeling, Helen C. and Phillips, Oliver L.}, title = {A calibration method for the crown illumination index for assessing forest light environments}, journal = {Forest Ecology and Management}, year = {2007}, volume = {242}, number = {2-3}, pages = {431--437}, url = {://WOS:000246268100036}, doi = {https://doi.org/10.1016/j.foreco.2007.01.060} } |
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Keeling, H.C. and Phillips, O.L. | The global relationship between forest productivity and biomass | 2007 | Global Ecology and Biogeography Vol. 16(5), pp. 618-631 |
article | DOI URL |
Abstract: Aim We aim to determine the empirical relationship between above-ground forest productivity and biomass. There are theoretical reasons to assume a relationship between forest structure and function, as both may be influenced by similar ecological factors such as moisture supply. Also, dynamic global vegetation model simulations imply that any increase in forest productivity driven by climate change will result in increases in biomass and therefore carbon storage. However, few studies have explored the strength and form of the relationship between forest productivity and biomass, whether in space or time. Location Global scale. Methods We collated a large data set of above-ground biomass (AGB) and above-ground net primary productivity (ANPP) and tested the extent to which spatial variation in forest biomass across the Earth can be predicted from forest productivity. Results The global ANPP-AGB relationship differs fundamentally from the strongly positive, linear relationship reported in earlier analyses, which mostly lacked tropical sites. AGB begins to peak at c. 15-20 Mg ha(-1) year(-1) ANPP, plateaus at ANPP textgreater 20-25 Mg ha(-1) year(-1), and may actually decline at higher levels of production. Main conclusions High turnover rates in high-productivity forests may limit AGB by promoting the dominance of species with a low wood density. Predicted increases in ANPP will not necessarily favour increases in forest carbon storage, especially if changes in productivity are accompanied by compositional shifts. | |||||
BibTeX:
@article{keeling_global_2007, author = {Keeling, Helen C. and Phillips, Oliver L.}, title = {The global relationship between forest productivity and biomass}, journal = {Global Ecology and Biogeography}, year = {2007}, volume = {16}, number = {5}, pages = {618--631}, url = {://WOS:000248959300007}, doi = {https://doi.org/10.1111/j.1466-8238.2007.00314.x} } |
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Keeling, H.C., Baker, T.R., Martinez, R.V., Monteagudo, A. and Phillips, O.L. | Contrasting patterns of diameter and biomass increment across tree functional groups in Amazonian forests | 2008 | Oecologia Vol. 158(3), pp. 521-534 |
article | DOI URL |
Abstract: Species' functional traits may help determine rates of carbon gain, with physiological and morphological trade-offs relating to shade tolerance affecting photosynthetic capacity and carbon allocation strategies. However, few studies have examined these trade-offs from the perspective of whole-plant biomass gain of adult trees. We compared tree-level annual diameter increments and annual above-ground biomass (AGB) increments in eight long-term plots in hyper-diverse northwest Amazonia to wood density (rho; a proxy for shade tolerance), whilst also controlling for resource supply (light and soil fertility). rho and annual diameter increment were negatively related, confirming expected differences in allocation associated with shade tolerance, such that light-demanding species allocate a greater proportion of carbon to diameter gain at the expense of woody tissue density. However, contrary to expectations, we found a positive relationship between rho and annual AGB increment in more fertile sites, although AGB gain did not differ significantly with rho class on low-fertility sites. Whole-plant carbon gain may be greater in shade-tolerant species due to higher total leaf area, despite lower leaf-level carbon assimilation rates. Alternatively, rates of carbon loss may be higher in more light-demanding species: higher rates of litterfall, respiration or allocation to roots, are all plausible mechanisms. However, the relationships between rho and AGB and diameter increments were weak; resource availability always exerted a stronger influence on tree growth rates. | |||||
BibTeX:
@article{keeling_contrasting_2008, author = {Keeling, Helen C. and Baker, Timothy R. and Martinez, Rodolfo Vasquez and Monteagudo, Abel and Phillips, Oliver L.}, title = {Contrasting patterns of diameter and biomass increment across tree functional groups in Amazonian forests}, journal = {Oecologia}, year = {2008}, volume = {158}, number = {3}, pages = {521--534}, note = {Edition: 2008/10/15}, url = {://WOS:000260856300013}, doi = {https://doi.org/10.1007/s00442-008-1161-4} } |
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Kayano, R., Souza R.A.F., M. and Andreoli | Relations between ENSO and the South Atlantic SST modes and their effects on the South American rainfall [BibTeX] |
2013 | International Journal of Climatology Vol. 33, pp. 2008-2023 |
article | |
BibTeX:
@article{kayano_relations_2013, author = {Kayano, R.V.; Souza, R.A.F., M.T.; Andreoli}, title = {Relations between ENSO and the South Atlantic SST modes and their effects on the South American rainfall}, journal = {International Journal of Climatology}, year = {2013}, volume = {33}, pages = {2008--2023} } |
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Kaufmann, T. and Fisch, G. | Estrutura da camada limite atmosférica acoplada a heterogeneidade superficial no sul da Amazônia – Experimento SAMBBA/2012 [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 500 - 503 |
article | |
BibTeX:
@article{kaufmann_estrutura_2013, author = {Kaufmann, Thomas and Fisch, Gilberto}, title = {Estrutura da camada limite atmosférica acoplada a heterogeneidade superficial no sul da Amazônia – Experimento SAMBBA/2012}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {500 -- 503} } |
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Kato, M.S.A., Kato, O.R., Denich, M. and Vlek, P.L.G. | Fire-free alternatives to slash-and-burn for shifting cultivation in the eastern Amazon region: the role of fertilizers | 1999 | Field Crops Research Vol. 62(2-3), pp. 225-237 |
article | DOI URL |
Abstract: Forest fires in slash-and-burn agriculture rank high in the list of environmental concerns. The objective of this study in Para State, Brazil, was to evaluate fire-free alternatives to burning of the slashed fellow vegetation for crop production in the humid tropics. Burning, mulching and incorporation of fallow biomass were compared in two successive cropping periods with rice, cowpea and cassava, with and without NPK fertilizer. In the traditional system, with slash-and-burn technology and without fertilizer, the shortening of the fallow period from 10 to 4 years caused a reduction of 30% only in the rice yields of the first cropping period. In the second cropping period, rice yields were lower in the area with 10 yeats of fallowing and similar with the shorter fallowed area when compared to the first season. Cowpea did not show any differences, whereas cassava yields decreased from the first to the second cropping period in both fallow situations. When fertilizers were applied, fallow periods beyond 1 years and doubled cropping periods appeared to have little effect on yields. Transforming the fellow vegetation into wood chips instead of slash burning reduced rice yields in the first cropping period 47 and 80% after 4 and 10 years of fallowing, respectively, and made cowpea production impossible after 10 years of fallowing. Cassava yields were not affected by fire free land preparation. Application of fertilizers raised yields from around 0.7 t ha(-1) to over 2 t ha(-1) for rice, and from around 0.2 t ha(-1) or less to around 1.5 t ha(-1) for cowpea, Fertilizer use was essential to obtain acceptable yields for the two crops under fire-free land preparation. Residual fertilizer doubled cassava yields. Comparing the two successive cropping periods, rice and cowpea yields increased, on average, 47 and 27%, respectively, in the second cropping period. irrespective of fallow age, but with fertilizer application. Over the entire cropping period, use of fertilizer led to a greater exploitation of soil N and K but not of P. The risk of soil degradation due to intensified cropping by shortened fallow or prolonged cropping periods is considered low, provided that sufficient plant material and nutrients are supplied to the soil by fire-free land preparation and fertilization. (C) 1999 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{kato_fire-free_1999, author = {Kato, M. S. A. and Kato, O. R. and Denich, M. and Vlek, P. L. G.}, title = {Fire-free alternatives to slash-and-burn for shifting cultivation in the eastern Amazon region: the role of fertilizers}, journal = {Field Crops Research}, year = {1999}, volume = {62}, number = {2-3}, pages = {225--237}, url = {://WOS:000080953100013}, doi = {https://doi.org/10.1016/s0378-4290(99)00021-0} } |
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Kasper, D., Forsberg, B.R., Amaral, J., Leitão, R., Py-Daniel, S., Bastos, W. and Malm, O. | Reservoir stratification affects methylmercury levels in river water, plankton and fish downstream from Balbina hydroelectric dam, Amazonas, Brazil [BibTeX] |
2014 | Environmental Science and Technology Vol. 48, pp. 1052-1040 |
article | |
BibTeX:
@article{kasper_reservoir_2014, author = {Kasper, D. and Forsberg, B. R. and Amaral, J.H.F. and Leitão, R.P. and Py-Daniel, S.S. and Bastos, W.R. and Malm, O.}, title = {Reservoir stratification affects methylmercury levels in river water, plankton and fish downstream from Balbina hydroelectric dam, Amazonas, Brazil}, journal = {Environmental Science and Technology}, year = {2014}, volume = {48}, pages = {1052--1040} } |
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Kasper, D., Forsberg, B., Almeida, R., Bastos, W. and Malm, O. | Metodologias de coleta, presevação e armazenamento de amostras de água para análise de mercúrio - Uma revisão [BibTeX] |
2015 | Quimica Nova Vol. 38, pp. 410-418 |
article | |
BibTeX:
@article{kasper_metodologias_2015, author = {Kasper, D. and Forsberg, B.R. and Almeida, R. and Bastos, W.R. and Malm, O.}, title = {Metodologias de coleta, presevação e armazenamento de amostras de água para análise de mercúrio - Uma revisão}, journal = {Quimica Nova}, year = {2015}, volume = {38}, pages = {410--418} } |
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Karl, T.G., Christian, T.J., Yokelson, R.J., Artaxo, P., Hao, W.M. and Guenther, A. | The Tropical Forest and Fire Emissions Experiment: method evaluation of volatile organic compound emissions measured by PTR-MS, FTIR, and GC from tropical biomass burning | 2007 | Atmospheric Chemistry and Physics Vol. 7(22), pp. 5883-5897 |
article | URL |
Abstract: Volatile Organic Compound (VOC) emissions from fires in tropical forest fuels were quantified using Proton-Transfer-Reaction Mass Spectrometry (PTRMS), Fourier Transform Infrared Spectroscopy (FTIR) and gas chromatography (GC) coupled to PTRMS (GC-PTR-MS). We investigated VOC emissions from 19 controlled laboratory fires at the USFS (United States Forest Service) Fire Sciences Laboratory and 16 fires during an intensive airborne field campaign during the peak of the burning season in Brazil in 2004. The VOC emissions were dominated by oxygenated VOCs (OVOC) (OVOC/NMHC similar to 4:1, NMHC: non-methane hydrocarbons) The specificity of the PTR-MS instrument, which measures the mass to charge ratio of VOCs ionized by H(3)O(+) ions, was validated by gas chromatography and by intercomparing in-situ measurements with those obtained from an open path FTIR instrument. Emission ratios for methyl vinyl ketone, methacrolein, crotonaldehyde, acrylonitrile and pyrrole were measured in the field for the first time. Our measurements show a higher contribution of OVOCs than previously assumed for modeling purposes. Comparison of fresh (textless15 min) and aged (textgreater1 h-1 d) smoke suggests altered emission ratios due to gas phase chemistry for acetone but not for acetaldehyde and methanol. Emission ratios for numerous, important, reactive VOCs with respect to acetonitrile (a biomass burning tracer) are presented. | |||||
BibTeX:
@article{karl_tropical_2007, author = {Karl, T. G. and Christian, T. J. and Yokelson, R. J. and Artaxo, P. and Hao, W. M. and Guenther, A.}, title = {The Tropical Forest and Fire Emissions Experiment: method evaluation of volatile organic compound emissions measured by PTR-MS, FTIR, and GC from tropical biomass burning}, journal = {Atmospheric Chemistry and Physics}, year = {2007}, volume = {7}, number = {22}, pages = {5883--5897}, url = {://WOS:000252166000010} } |
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Karl, T., Guenther, A., Yokelson, R.J., Greenberg, J., Potosnak, M., Blake, D.R. and Artaxo, P. | The tropical forest and fire emissions experiment: Emission, chemistry, and transport of biogenic volatile organic compounds in the lower atmosphere over Amazonia | 2007 | Journal of Geophysical Research-Atmospheres Vol. 112(D18) |
article | DOI URL |
Abstract: Airborne and ground-based mixing ratio and flux measurements using eddy covariance (EC) and for the first time the mixed layer gradient (MLG) and mixed layer variance (MLV) techniques are used to assess the impact of isoprene and monoterpene emissions on atmospheric chemistry in the Amazon basin. Average noon isoprene (7.8 +/- 2.3 mg/m(2)/h) and monoterpene fluxes (1.2 +/- 0.5 mg/m(2)/h)compared well between ground and airborne measurements and are higher than fluxes estimated in this region during other seasons. The biogenic emission model, Model of Emissions of Gases and Aerosols from Nature (MEGAN), estimates fluxes that are within the model and measurement uncertainty and can describe the large observed variations associated with land-use change in the region north-west of Manaus. Isoprene and monoterpenes accounted for similar to 75% of the total OH reactivity in this region and are important volatile organic compounds (VOCs) for modeling atmospheric chemistry in Amazonia. The presence of fair weather clouds ( cumulus humilis) had an important impact on the vertical distribution and chemistry of VOCs through the planetary boundary layer (PBL), the cloud layer, and the free troposphere (FT). Entrainment velocities between 10: 00 and 11: 30 local time ( LT) are calculated to be on the order of 8-10 cm/s. The ratio of methyl-vinyl-ketone (MVK) and methacrolein (MAC) ( unique oxidation products of isoprene chemistry) with respect to isoprene showed a pronounced increase in the cloud layer due to entrainment and an increased oxidative capacity in broken cloud decks. A decrease of the ratio in the lower free troposphere suggests cloud venting through activated clouds. OH modeled in the planetary boundary layer using a photochemical box model is much lower than OH calculated from a mixed layer budget approach. An ambient reactive sesquiterpene mixing ratio of 1% of isoprene would be sufficient to explain most of this discrepancy. Increased OH production due to increased photolysis in the cloud layer balances the low OH values modeled for the planetary boundary layer. The intensity of segregation ( Is) of isoprene and OH, defined as a relative reduction of the reaction rate constant due to incomplete mixing, is found to be significant: up to 39 +/- 7% in the similar to 800-m-deep cloud layer. The effective reaction rate between isoprene and OH can therefore vary significantly in certain parts of the lower atmosphere. | |||||
BibTeX:
@article{karl_tropical_2007-1, author = {Karl, Thomas and Guenther, Alex and Yokelson, Robert J. and Greenberg, Jim and Potosnak, Mark and Blake, Donald R. and Artaxo, Paulo}, title = {The tropical forest and fire emissions experiment: Emission, chemistry, and transport of biogenic volatile organic compounds in the lower atmosphere over Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2007}, volume = {112}, number = {D18}, url = {://WOS:000249684900005}, doi = {https://doi.org/10.1029/2007jd008539} } |
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Karl, T., Guenther, A., Turnipseed, A., Tyndall, G., Artaxo, P. and Martin, S. | Rapid formation of isoprene photo-oxidation products observed in Amazonia | 2009 | Atmospheric Chemistry and Physics Vol. 9(20), pp. 7753-7767 |
article | URL |
Abstract: Isoprene represents the single most important reactive hydrocarbon for atmospheric chemistry in the tropical atmosphere. It plays a central role in global and regional atmospheric chemistry and possible climate feedbacks. Photo-oxidation of primary hydrocarbons (e. g. isoprene) leads to the formation of oxygenated VOCs (OVOCs). The evolution of these intermediates affects the oxidative capacity of the atmosphere (by reacting with OH) and can contribute to secondary aerosol formation, a poorly understood process. An accurate and quantitative understanding of VOC oxidation processes is needed for model simulations of regional air quality and global climate. Based on field measurements conducted during the Amazonian Aerosol Characterization Experiment (AMAZE-08) we show that the production of certain OVOCs (e. g. hydroxyacetone) from isoprene photo-oxidation in the lower atmosphere is significantly underpredicted by standard chemistry schemes. Recently reported fast secondary production could explain 50% of the observed discrepancy with the remaining part possibly produced via a novel primary production channel, which has been proposed theoretically. The observations of OVOCs are also used to test a recently proposed HO(x) recycling mechanism via degradation of isoprene peroxy radicals. If generalized our observations suggest that prompt photochemical formation of OVOCs and other uncertainties in VOC oxidation schemes could result in uncertainties of modelled OH reactivity, potentially explaining a fraction of the missing OH sink over forests which has previously been largely attributed to a missing source of primary biogenic VOCs. | |||||
BibTeX:
@article{karl_rapid_2009, author = {Karl, T. and Guenther, A. and Turnipseed, A. and Tyndall, G. and Artaxo, P. and Martin, S.}, title = {Rapid formation of isoprene photo-oxidation products observed in Amazonia}, journal = {Atmospheric Chemistry and Physics}, year = {2009}, volume = {9}, number = {20}, pages = {7753--7767}, url = {://WOS:000271240500006} } |
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Kalif, K.A.B., Azevedo-Ramos, C., Moutinho, P. and Malcher, S.A.O. | The effect of logging on the ground-foraging ant community in Eastern Amazonia | 2001 | Studies on Neotropical Fauna and Environment Vol. 36(3), pp. 215-219 |
article | DOI URL |
Abstract: In order to determine the suitability of ants as indicator organisms for habitat disruption in tropical forests, we studied the effects of both high and low impact logging on ant communities in northeastern Para State, in the Brazilian Amazon. We collected ants from logged forests and unlogged forest sites with Winkler bags throughout the 1998 rainy season (January and April) and the following dry season (July and September). Both methods of timber harvesting showed impacts on ant community composition when compared with unlogged forest, although these impacts did not include modifications in total species richness or the relative contribution of each ant subfamily to the total number of species. Instead, logging induced alterations took place at the level of species and genera. A 2-fold reduction in the dominance of ants of the highly diverse genus Pheidole was associated with forest alterations in high-impact logging sites. Thus, logging in Amazonia can be seen to promote species shifts in ant communities, without, however, altering species richness. Ants of the genus Pheidole are potentially useful indicators for forest disturbances resulting from timber extraction. | |||||
BibTeX:
@article{kalif_effect_2001, author = {Kalif, K. A. B. and Azevedo-Ramos, C. and Moutinho, P. and Malcher, S. A. O.}, title = {The effect of logging on the ground-foraging ant community in Eastern Amazonia}, journal = {Studies on Neotropical Fauna and Environment}, year = {2001}, volume = {36}, number = {3}, pages = {215--219}, url = {://WOS:000172796800007}, doi = {https://doi.org/10.1076/snfe.36.3.215.2119} } |
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Junk, M., Lourival, R., Wittmann, F., Kandus, P., Lacerda, L., Bozelli, R., Esteves, F., Nunes da Cunha, C., Maltchik, L., Schöngart, J., Schaeffer-Novelli, Y., Agostinho AA., W. and Piedade | Brazilian wetlands: their definition, delineation, and classification for research, sustainable management, and protection [BibTeX] |
2014 | Aquatic Conservation Vol. 24, pp. 5-22 |
article | |
BibTeX:
@article{junk_brazilian_2014, author = {Junk, MTF; Lourival, R; Wittmann, F; Kandus, P; Lacerda, LD; Bozelli, RL; Esteves, FA; Nunes da Cunha, C; Maltchik, L; Schöngart, J; Schaeffer-Novelli, Y; Agostinho, AA., WJ; Piedade}, title = {Brazilian wetlands: their definition, delineation, and classification for research, sustainable management, and protection}, journal = {Aquatic Conservation}, year = {2014}, volume = {24}, pages = {5--22} } |
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Junk, W., Wittmann, F., Schöngart, J. and Piedade, M. | A classification of the major habitats of Amazonian black-water river floodplains and a comparison with their white-water counterparts [BibTeX] |
2015 | Wetlands Ecology and Management Vol. 23, pp. 677-693 |
article | |
BibTeX:
@article{junk_classification_2015, author = {Junk, WJ. and Wittmann, F. and Schöngart, J. and Piedade, MTF.}, title = {A classification of the major habitats of Amazonian black-water river floodplains and a comparison with their white-water counterparts}, journal = {Wetlands Ecology and Management}, year = {2015}, volume = {23}, pages = {677--693} } |
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Júnior, M., Neto, F., Figueira, A.P., Barreto, W.M., Tapajós, R., Aguiar, D.R., Silva, H. and Silva, R. | Fluxos de dióxido de carbono na interface solo-atmosfera na Floresta Nacional do Tapajós - o ano de 2005 [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 145-148 |
article | |
BibTeX:
@article{junior_fluxos_2009, author = {Júnior, M. and Neto, Furtado and Figueira, Antonio P. and Barreto, Wilderclay M. and Tapajós, Raphael and Aguiar, Diego R. and Silva, Hudson and Silva, Rodrigo}, title = {Fluxos de dióxido de carbono na interface solo-atmosfera na Floresta Nacional do Tapajós - o ano de 2005}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {145--148} } |
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Jung, H.C. and Alsdorf, D. | Repeat-pass multi-temporal interferometric SAR coherence variations with Amazon floodplain and lake habitats | 2010 | International Journal of Remote Sensing Vol. 31(4), pp. 881-901 |
article | DOI URL |
Abstract: We have analysed interferometric coherence variations in Japanese Earth Resources Satellite (JERS-1) L-band synthetic aperture radar (SAR) data at three central Amazon sites: Lake Balbina, Cabaliana and Solimoes-Purus. Because radar pulse interactions with inundated vegetation typically follow a double-bounce travel path that returns energy to the antenna, coherence will vary with vegetation type as well as with physical and temporal baselines. Lake Balbina consists mostly of upland forests and inundated trunks of dead, leafless trees whereas Cabaliana and Solimoes-Purus are dominated by flooded forests. Balbina has higher coherence values than either Cabaliana or Solimoes-Purus probably because the dead, leafless trees support strong double-bounce returns. The mean coherences of flooded woodland are 0.28 in Balbina and 0.11 in both Cabaliana and Solimoes-Purus. With increasing temporal baselines, flooded and nonflooded wetland habitats show a steadily decreasing trend in coherence values whereas terra-firme and especially open-water habitats have little variation and remain lower in value. Flooded and nonflooded wetland coherence varies with the season whereas terra-firme and open water do not have similarly evident seasonal variations. For example, flooded habitats in all three study regions show annual peaks in coherence values that are typically 0.02 greater than coherence values from temporal baselines 180 days later, yet open water shows no variation with time. Our findings suggest that, despite overall low coherence values, repeat-pass interferometric coherence of flooded habitats is capable of showing the annual periodicity of the Amazon flood wave. | |||||
BibTeX:
@article{jung_repeat-pass_2010, author = {Jung, Hahn Chul and Alsdorf, Doug}, title = {Repeat-pass multi-temporal interferometric SAR coherence variations with Amazon floodplain and lake habitats}, journal = {International Journal of Remote Sensing}, year = {2010}, volume = {31}, number = {4}, pages = {881--901}, url = {://WOS:000275877800004}, doi = {https://doi.org/10.1080/01431160902902609} } |
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Juarez, R., Goulden, M., Myneni, R., Fu, R., Bernardes, S. and Gao, H. | An empirical approach to retrieving monthly evapotranspiration over Amazonia [BibTeX] |
2008 | International Journal of Remote Sensing Vol. 29(24), pp. 7045-7063 |
article | |
BibTeX:
@article{juarez_empirical_2008, author = {Juarez, R.I.N. and Goulden, M.L. and Myneni, R.B. and Fu, R. and Bernardes, S. and Gao, H.}, title = {An empirical approach to retrieving monthly evapotranspiration over Amazonia}, journal = {International Journal of Remote Sensing}, year = {2008}, volume = {29}, number = {24}, pages = {7045--7063} } |
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Juarez, R.I.N., da Rocha, H.R., Silva e Figueira, A.M., Goulden, M.L. and Miller, S.D. | An improved estimate of leaf area index based on the histogram analysis of hemispherical photographs | 2009 | Agricultural and Forest Meteorology Vol. 149(6-7), pp. 920-928 |
article | DOI URL |
Abstract: Leaf area index (LAI) is a key parameter that affects the surface fluxes of energy, mass, and momentum over vegetated lands, but observational measurements are scarce, especially in remote areas with complex canopy structure. In this paper we present an indirect method to calculate the LAI based on the analyses of histograms of hemispherical photographs. The optimal threshold value (OTV), the gray-level required to separate the background (sky) and the foreground (leaves), was analytically calculated using the entropy crossover method (Sahoo, P.K., Slaaf, D.W., Albert, T.A., 1997. Threshold selection using a minimal histogram entropy difference. Optical Engineering 36(7) 1976-1981). The OTV was used to calculate the LAI using the well-known gap fraction method. This methodology was tested in two different ecosystems, including Amazon forest and pasturelands in Brazil. In general, the error between observed and calculated LAI was similar to 6%. The methodology presented is suitable for the calculation of LAI since it is responsive to sky conditions, automatic, easy to implement, faster than commercially available software, and requires less data storage. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{juarez_improved_2009, author = {Juarez, Robinson I. Negron and da Rocha, Humberto Ribeiro and Silva e Figueira, Adelaine Michela and Goulden, Michael L. and Miller, Scott D.}, title = {An improved estimate of leaf area index based on the histogram analysis of hemispherical photographs}, journal = {Agricultural and Forest Meteorology}, year = {2009}, volume = {149}, number = {6-7}, pages = {920--928}, url = {://WOS:000265363900002}, doi = {https://doi.org/10.1016/j.agrformet.2008.11.012} } |
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Joslin, A.H., Markewitz, D., Morris, L.A., Oliveira, F.D., Figueiredo, R.O. and Kato, O.R. | Five native tree species and manioc under slash-and-mulch agroforestry in the eastern Amazon of Brazil: plant growth and soil responses | 2011 | Agroforestry Systems Vol. 81(1), pp. 1-14 |
article | DOI URL |
Abstract: Throughout the Amazon of Brazil, manioc (Manihot esculenta) is a staple crop produced through slash-and-burn agriculture. Nutrient losses during slash-and-burn can be large and nutrient demand by food crops so great that fields are often abandoned after two years. In recent decades, farmers have reduced the fallow phase from 20 to similar to 5 years, limiting plant nutrient accumulation to sustain crop yields. Improved fallows through simultaneous planting of trees with food crops may accelerate nutrient re-accumulation. In addition, slash-and-mulch technology may prevent loss of nutrients due to burning and mulch decomposition may serve as a slow-release source of nutrients. This study in Para, Brazil, in a 7-year-old secondary forest following slashing and mulching of the vegetation, involved two main plot treatments (with and without P and K fertilizers) and two sub-plot treatments (with or without a N(2)-fixer Inga edulis). A mixed-culture of trees and manioc was planted in all plots. P and K fertilizer increased tree mortality due to weed competition but growth of surviving trees in four of the five tree species tested also increased as did biomass production of manioc. In the N(2)-fixer treatment trends of greater growth and survival of four of five tree species and manioc biomass were also observed. Fertilization increased the biomass of competing vegetation, but there was a fertilizer by N(2)-fixer interaction as I. edulis caused a reduction in competing biomass in the fertilized treatment. After one year, fertilization increased decomposition of the mulch such that Ca, Mg, and N contents within the mulch all decreased. In contrast, P and K contents of mulch increased in all treatments. No influence of the N(2)-fixer on 0-10 cm soil N contents was observed. Two years after establishment, this agroforestry system succeeded in growing a manioc crop and leaving a well-maintained tree fallow after the crop harvest. | |||||
BibTeX:
@article{joslin_five_2011, author = {Joslin, Aaron H. and Markewitz, Daniel and Morris, Lawrence A. and Oliveira, Francisco DeAssis and Figueiredo, Ricardo O. and Kato, Oswaldo R.}, title = {Five native tree species and manioc under slash-and-mulch agroforestry in the eastern Amazon of Brazil: plant growth and soil responses}, journal = {Agroforestry Systems}, year = {2011}, volume = {81}, number = {1}, pages = {1--14}, url = {://WOS:000284953600001}, doi = {https://doi.org/10.1007/s10457-010-9356-1} } |
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Marengo, J.A., Alves, L.M., Soares, W.R. and Williams, E.R. | Extreme Seasonal Climate Variations in the Amazon Basin: Droughts and Floods [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 55-76 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_extreme_2016, author = {José A. Marengo, Lincloln M. Alves, Wagner R. Soares, Earle R. Williams}, title = {Extreme Seasonal Climate Variations in the Amazon Basin: Droughts and Floods}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {55--76}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Jordao, W., Zanchi, F., Ferreira, D., Pagani, C., Luizão, F., Neves, J. and Duarte, M. | Variabilidade do índice de área foliar em campos naturais e floresta de transição na região Sul do Amazonas [BibTeX] |
2015 | Revista Ambiente & Água Vol. 10, pp. 363-375 |
article | |
BibTeX:
@article{jordao_variabilidade_2015, author = {Jordao, W.H.C. and Zanchi, F.B. and Ferreira, D.M.M. and Pagani, C.H. and Luizão, F.J. and Neves, J.R.D. and Duarte, M.L.}, title = {Variabilidade do índice de área foliar em campos naturais e floresta de transição na região Sul do Amazonas}, journal = {Revista Ambiente & Água}, year = {2015}, volume = {10}, pages = {363--375} } |
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Joiner, J., Yoshida, Y., Vasilkov, A.P., Corp, L.A. and Middleton, E.M. | First observations of global and seasonal terrestrial chlorophyll fluorescence from space | 2011 | Biogeosciences Vol. 8(3), pp. 637-651 |
article | DOI URL |
Abstract: Remote sensing of terrestrial vegetation fluorescence from space is of interest because it can potentially provide global coverage of the functional status of vegetation. For example, fluorescence observations may provide a means to detect vegetation stress before chlorophyll reductions take place. Although there have been many measurements of fluorescence from ground-and airborne-based instruments, there has been scant information available from satellites. In this work, we use high-spectral resolution data from the Thermal And Near-infrared Sensor for carbon Observation - Fourier Transform Spectrometer (TANSO-FTS) on the Japanese Greenhouse gases Observing SATellite (GOSAT) that is in a sun-synchronous orbit with an equator crossing time near 13:00 LT. We use filling-in of the potassium (K) I solar Fraunhofer line near 770 nm to derive chlorophyll fluorescence and related parameters such as the fluorescence yield at that wavelength. We map these parameters globally for two months (July and December 2009) and show a full seasonal cycle for several different locations, including two in the Amazonia region. We also compare the derived fluorescence information with that provided by the MODIS Enhanced Vegetation Index (EVI). These comparisons show that for several areas these two indices exhibit different seasonality and/or relative intensity variations, and that changes in fluorescence frequently lead those seen in the EVI for those regions. The derived fluorescence therefore provides information that is related to, but independent of the reflectance. | |||||
BibTeX:
@article{joiner_first_2011, author = {Joiner, J. and Yoshida, Y. and Vasilkov, A. P. and Corp, L. A. and Middleton, E. M.}, title = {First observations of global and seasonal terrestrial chlorophyll fluorescence from space}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {3}, pages = {637--651}, url = {://WOS:000288911300007}, doi = {https://doi.org/10.5194/bg-8-637-2011} } |
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Johnson, M.S., Weiler, M., Couto, E.G., Riha, S.J. and Lehmann, J. | Storm pulses of dissolved CO(2) in a forested headwater Amazonian stream explored using hydrograph separation | 2007 | Water Resources Research Vol. 43(11) |
article | DOI URL |
Abstract: Dissolved CO(2) dynamics in stormflow and event water versus preevent water contributions to storm hydrographs were assessed in a forested headwater catchment of the Brazilian Amazon using high-frequency data. We applied the transfer function hydrograph separation model (TRANSEP) using specific conductance as a conservative tracer, finding preevent water to average 0.79 +/- 0.03 of storm discharge (mean +/- 1 SE for n = 14 storms). In situ, direct measurements of dissolved CO2 were able to capture new hydrobiogeochemical processes in real time, including CO2 pulses observed on the falling limb of storm hydrographs, the magnitudes of which were inversely related to preevent water fractions (r = -0.97, p textless 0.0001). | |||||
BibTeX:
@article{johnson_storm_2007, author = {Johnson, Mark S. and Weiler, Markus and Couto, Eduardo Guimaraes and Riha, Susan J. and Lehmann, Johannes}, title = {Storm pulses of dissolved CO(2) in a forested headwater Amazonian stream explored using hydrograph separation}, journal = {Water Resources Research}, year = {2007}, volume = {43}, number = {11}, url = {://WOS:000251063900004}, doi = {https://doi.org/10.1029/2007wr006359} } |
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Johnson, M.S., Lehmann, J., Steenhuis, T.S., de Oliveira, L.V. and Fernandes, E.C.M. | Spatial and temporal variability of soil water repellency of Amazonian pastures | 2005 | Australian Journal of Soil Research Vol. 43(3), pp. 319-326 |
article | DOI URL |
Abstract: Fire is commonly used to establish and maintain pastures in the Amazon. Fire is also known to induce soil water repellency but few published data exist for the humid tropics. The objectives of this study were to characterise the intensity and spatial variability of water repellency on previously burned pasture soils in the Amazon, and its effect on the nutrient status of the forage grass Brachiaria brizantha (Hochst.) Stapf. Surface soils of pastures and forests in north-western Mato Grosso, Brazil, were found to exhibit soil water repellency using MED and WDPT tests. Soil water repellency was found only within 0 - 0.01 m of the mineral soil surface, with soil below 0.01 m found to be hydrophilic in all cases. Spatial variability of repellency was high for both pasture and forest soils. For pasture soils, soil water repellency was strongest on recently burned pastures, which exhibited some extremely high values ( MED textgreater 8M). Repellency decreased rapidly with time following burning. Increasing soil water repellency was associated with decreasing N: P ratios of B. brizantha above-ground biomass (r(2) = 0.66, P= 0.004). These findings indicate that soil water repellency and pasture productivity are inversely related. Since pasture abandonment fuels continued deforestation, disrupting the processes causing pasture degradation may lead to more sustainable land use in the Amazon. | |||||
BibTeX:
@article{johnson_spatial_2005, author = {Johnson, M. S. and Lehmann, J. and Steenhuis, T. S. and de Oliveira, L. V. and Fernandes, E. C. M.}, title = {Spatial and temporal variability of soil water repellency of Amazonian pastures}, journal = {Australian Journal of Soil Research}, year = {2005}, volume = {43}, number = {3}, pages = {319--326}, url = {://WOS:000229373800011}, doi = {https://doi.org/10.1071/sr04097} } |
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Johnson, M.S., Lehmann, J., Selva, E.C., Abdo, M., Riha, S. and Couto, E.G. | Organic carbon fluxes within and streamwater exports from headwater catchments in the southern Amazon | 2006 | Hydrological Processes Vol. 20(12), pp. 2599-2614 |
article | DOI URL |
Abstract: Forms and quantities of organic carbon (C) fluxes at the soil surface, and organic C exports from four small (1-2 ha) headwater catchments were quantified and contrasted in the seasonally dry southern Amazon for I year to compare C fluxes within the terrestrial ecosystem with exports to the aquatic ecosystem. At the soil surface, the flux of litterfall C was 43 times greater than the dissolved organic carbon (DOC) flux in throughfall, with the highest rates of C deposition during the dry season. The form and timing of organic C was reversed for watershed exports, where DOC comprised 59% of the annual total organic C export, and exports were greatest during the 4-month rainy season (63% of total annual exports). Fine particulate organic carbon (FPOC) in streamwater was a substantially larger flux than coarse particulate organic carbon (CPOC), representing 37 and 4% of total annual organic C exports, respectively. Particulate organic C exports exhibited substantial seasonal variability, with FPOC and CPOC mobilized primarily in the rainy season and strongly connected to storm events. Storm flow comprised 6% of total streamflow for the year studied, and 10% of streamflow during the rainy season. In the rainy season, over 90% of FPOC exports were transported by storm flow, while only 32% of DOC exports were exported by storm flow during this period. Streamwater DOC concentrations were found to increase linearly with increasing terrestrial litterfall during the dry season (r(2) = 0.92, p textless 0.001), indicating that in-stream processing of allochthonous litterfall is an important source of DOC during the dry season. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{johnson_organic_2006, author = {Johnson, Mark S. and Lehmann, Johannes and Selva, Evandro Carlos and Abdo, Mara and Riha, Susan and Couto, Eduardo Guimaraes}, title = {Organic carbon fluxes within and streamwater exports from headwater catchments in the southern Amazon}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2599--2614}, url = {://WOS:000239670800009}, doi = {https://doi.org/10.1002/hyp.6218} } |
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Johnson, M.S., Lehmann, J., Riha, S.J., Krusche, A.V., Richey, J.E., Ometto, J.P.H.B. and Couto, E.G. | CO(2) efflux from Amazonian headwater streams represents a significant fate for deep soil respiration | 2008 | Geophysical Research Letters Vol. 35(17) |
article | DOI URL |
Abstract: Large Amazonian rivers are known to emit substantial amounts of CO(2) to the atmosphere, while the magnitude of CO(2) degassing from small streams remains a major unknown in regional carbon budgets. We found that 77% of carbon transported by water from the landscape was as terrestrially-respired CO(2) dissolved within soils, over 90% of which evaded to the atmosphere within headwater reaches of streams. Hydrologic transport of dissolved CO(2) was equivalent to nearly half the gaseous CO(2) contributions from deep soil (textgreater 2 m) to respiration at the soil surface. Dissolved CO(2) in emergent groundwater was isotopically consistent with soil respiration, and demonstrated strong agreement with deep soil CO(2) concentrations and seasonal dynamics. During wet seasons, deep soil (2-8 m) CO2 concentration profiles indicated gaseous diffusion to deeper layers, thereby enhancing CO(2) drainage to streams. Groundwater discharge of CO(2) and its subsequent evasion is a significant conduit for terrestrially-respired carbon in tropical headwater catchments. | |||||
BibTeX:
@article{johnson_co2_2008, author = {Johnson, Mark S. and Lehmann, Johannes and Riha, Susan J. and Krusche, Alex V. and Richey, Jeffrey E. and Ometto, Jean Pierre H. B. and Couto, Eduardo Guimaraes}, title = {CO(2) efflux from Amazonian headwater streams represents a significant fate for deep soil respiration}, journal = {Geophysical Research Letters}, year = {2008}, volume = {35}, number = {17}, url = {://WOS:000258999300005 http://www.agu.org/pubs/crossref/2008/2008GL034619.shtml}, doi = {https://doi.org/10.1029/2008gl034619} } |
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Johnson, M.S., Lehmann, J., Couto, E.G., Novaes Filho, J.P. and Riha, S.J. | DOC and DIC in flowpaths of Amazonian headwater catchments with hydrologically contrasting soils | 2006 | Biogeochemistry Vol. 81(1), pp. 45-57 |
article | DOI URL |
Abstract: Organic and inorganic carbon (C) fluxes transported by water were evaluated for dominant hydrologic flowpaths on two adjacent headwater catchments in the Brazilian Amazon with distinct soils and hydrologic responses from September 2003 through April 2005. The Ultisol-dominated catchment produced 30% greater volume of storm-related quickflow (overland flow and shallow subsurface flow) compared to the Oxisol-dominated catchment. Quickflow fluxes were equivalent to 3.2 +/- 0.2% of event precipitation for the Ultisol catchment, compared to 2.5 +/- 0.3% for the Oxisol-dominated watershed (mean response +/- 1 SE, n = 27 storms for each watershed). Hydrologic responses were also faster on the Ultisol watershed, with time to peak flow occurring 10 min earlier on average as compared to the runoff response on the Oxisol watershed. These different hydrologic responses are attributed primarily to large differences in saturated hydraulic conductivity (K-s). Overland flow was found to be an important feature on both watersheds. This was evidenced by the response rates of overland flow detectors (OFDs) during the rainy season, with overland flow intercepted by 54 +/- 0.5% and 65 +/- 0.5% of OFDs for the Oxisol and Ultisol watersheds respectively during biweekly periods. Small volumes of quickflow correspond to large fluxes of dissolved organic C (DOC); DOC concentrations of the hydrologic flowpaths that comprise quickflow are an order of magnitude higher than groundwater flowpaths fueling base flow (19.6 +/- 1.7 mg l(-1) DOC for overland flow and 8.8 +/- 0.7 mg l(-1) DOC for shallow subsurface flow versus 0.50 +/- 0.04,mg l(-1) DOC in emergent groundwater). Concentrations of dissolved inorganic C (DIC, as dissolved CO2-C plus HCO3--C) in groundwater were found to be an order of magnitude greater than quickflow DIC concentrations (21.5 mg l(-1) DIC in emergent groundwater versus 1.1 mg l(-1) DIC in overland flow). The importance of deeper flowpaths in the transport of inorganic C to streams is indicated by the 40:1 ratio of DIC:DOC for emergent groundwater. Dissolved CO2-C represented 92% of DIC in emergent groundwater. Results from this study illustrate a highly dynamic and tightly coupled linkage between the C cycle and the hydrologic cycle for both Ultisol and Oxisol landscapes: organic C fluxes strongly tied to flowpaths associated with quickflow, and inorganic C (particularly dissolved CO2) transported via deeper flowpaths. | |||||
BibTeX:
@article{johnson_doc_2006, author = {Johnson, Mark S. and Lehmann, Johannes and Couto, Eduardo Guimaraes and Novaes Filho, Joao Paulo and Riha, Susan J.}, title = {DOC and DIC in flowpaths of Amazonian headwater catchments with hydrologically contrasting soils}, journal = {Biogeochemistry}, year = {2006}, volume = {81}, number = {1}, pages = {45--57}, url = {://WOS:000240980500004}, doi = {https://doi.org/10.1007/s10533-006-9029-3} } |
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Johnson, M.S. and Lehmann, J. | Double-funneling of trees: Stemflow and root-induced preferential flow | 2006 | Ecoscience Vol. 13(3), pp. 324-333 |
article | DOI URL |
Abstract: Trees partition rainfall into throughfall and stemflow, resulting in a spatial distribution of nutrient and water fluxes reaching the soil centred on the trunks of trees. Stemflow fluxes of water and nutrients are then funneled preferentially belowground along tree roots and other preferential flow paths, bypassing much of the bulk soil. This double funneling leads to increased soil chemical, biological, and hydrological heterogeneity, which has been shown to persist for decades. In this paper, we review nutrient fluxes of stemflow water for a variety of tree species and climates. The amount of precipitation partitioned by trees to stemflow ranges over more than three orders of magnitude, accounting for 0.07-22% of incident rainfall in a range of precipitation regimes (600-7100 mm.y(-1)). Sternflow fluxes of NO3- and K were found to be larger for species with greater stemflow partitioning, regardless of climate type. While stemflow volumes may increase in relation to increasing precipitation, stemflow nutrient concentrations tend to become more dilute. On an annual basis, however, it appears that plant canopy morphology is strongly related to stemflow fluxes for plant-mobile nutrients such as K (r(2) = 0.64) and NO3- (r(2) = 0.61). Root-induced preferential flow provides an additional feedback mechanism in nutrient cycling by which stemflow-derived nutrient fluxes are delivered to the rhizosphere. | |||||
BibTeX:
@article{johnson_double-funneling_2006, author = {Johnson, Mark S. and Lehmann, Johannes}, title = {Double-funneling of trees: Stemflow and root-induced preferential flow}, journal = {Ecoscience}, year = {2006}, volume = {13}, number = {3}, pages = {324--333}, url = {://WOS:000240960500005}, doi = {https://doi.org/10.2980/i1195-6860-13-3-324.1} } |
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Johnson, M., Couto, E., Pinto Jr, O., Milesi, J., Amorim, R., Messias, I.M. and Biudes, M. | Soil CO2 Dynamics in a Tree Island Soil of the Pantanal: The Role of Soil Water Potential [BibTeX] |
2013 | PLoS ONE Vol. 8(ID - 2778(6), pp. e64874 |
article | DOI |
BibTeX:
@article{johnson_soil_2013, author = {Johnson, M.S. and Couto, E.G. and Pinto Jr, O.B. and Milesi, J. and Amorim, R.S.S. and Messias, I.A. M. and Biudes, M.S.}, title = {Soil CO2 Dynamics in a Tree Island Soil of the Pantanal: The Role of Soil Water Potential}, journal = {PLoS ONE}, year = {2013}, volume = {8(ID - 2778}, number = {6}, pages = {e64874}, doi = {https://doi.org/10.1371/journal.pone.0064874} } |
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Johnson, M.S., Couto, E.G., Abdo, M. and Lehmann, J. | Fluorescence index as an indicator of dissolved organic carbon quality in hydrologic flowpaths of forested tropical watersheds | 2011 | Biogeochemistry Vol. 105(1-3), pp. 149-157 |
article | DOI URL |
Abstract: Over two hundred samples were collected in tropical headwater forested catchments in the lowland Amazon basin near Juruena, Mato Grosso Brazil. These were analyzed for fluorescence characteristics and DOC concentrations, and represented a range of terrestrial hydrologic flowpaths and first-order streams during baseflow and stormflow conditions. The fluorescence index (FI) of McKnight et al. (2001) was found to have a significant relationship with DOC concentrations for stream water at baseflow conditions, but FI values within individual terrestrial flowpaths and stormflow varied little for the range of DOC concentrations observed. FI values were seen to increase for increasing residence time of water within the terrestrial ecosystem, while DOC concentration decreased for increasing hydrologic residence time. The FI of terrestrial flow paths indicated that DOC became increasingly characterized by microbially derived carbon for flow paths with longer residence times, on the order through fall and overland flow textless percolating soil water textless groundwater. Base flow samples of stream water had a mean FI value of 1.78, compared with 1.51 and 1.44 for through fall and overland flow, respectively, and 1.65 for percolating soil water. The FI values for stream water at base flow were also seen to vary seasonally, and were inversely proportional to DOC concentrations over time. | |||||
BibTeX:
@article{johnson_fluorescence_2011, author = {Johnson, Mark S. and Couto, Eduardo G. and Abdo, Mara and Lehmann, Johannes}, title = {Fluorescence index as an indicator of dissolved organic carbon quality in hydrologic flowpaths of forested tropical watersheds}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {149--157}, url = {://WOS:000294501100011}, doi = {https://doi.org/10.1007/s10533-011-9595-x} } |
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Johnson Galbraith, D.G.M.D.D.H.G.M.R.A.T.K.V.H.v.R.C.M.A.P.O.L.B.R.J.W.F.T.R.L.G.G.F.S.Q.C.A.C.B.C.P.S.G.K.B.M.P.M.P.Z.K.A.-D.E.A.d.O.A.A.I.A.A.A.L.E.O.C.A.-M.A.A.E.J.M.M.A.L.A.G.A.B.C.B.J.B.D.B.R.C.J.C.J.C.A.C.V.F.L.d.C.A.C.D.F.A.F.L.H.N.H.E.N.K.T.J.L.S.G.L.W.F.L.J.L.T.M.Y.M.B.M.B.H.M.D.C.L.M.C.N.D.A.P.G.P.-C.M.P.N.C.A.P.L.P.A.R.-A.H.R.A.R.A.S.R.P.S.M.S.J.t.S.H.T.J.T.R.T.M.T.-L.A.v.d.H.G.M.F.V.R.G.V.I.C.V.E.V.V.A.and.B.T.R.M.O. | Variation in stem mortality rates determines patterns of aboveground biomass in Amazonian forests: implications for dynamic global vegetation models [BibTeX] |
2016 | Global Change Biology, pp. 1-17 | article | DOI |
BibTeX:
@article{johnson_variation_2016, author = {Johnson, Galbraith, D., Gloor, M., De Deurwaerder, H., Guimberteau, M., Rammig, A., Thonicke, K., Verbeeck, H., von Randow, C., Monteagudo, A., Phillips, O. L., Brienen, R. J. W., Feldpausch, T. R., Lopez Gonzalez, G., Fauset, S., Quesada, C. A., Christoffersen, B., Ciais, P., Sampaio, G., Kruijt, B., Meir, P., Moorcroft, P., Zhang, K., Alvarez-Davila, E., Alves de Oliveira, A., Amaral, I., Andrade, A., Aragao, L. E. O. C., Araujo-Murakami, A., Arets, E. J. M. M., Arroyo, L., Aymard, G. A., Baraloto, C., Barroso, J., Bonal, D., Boot, R., Camargo, J., Chave, J., Cogollo, A., Cornejo Valverde, F., Lola da Costa, A. C., Di Fiore, A., Ferreira, L., Higuchi, N., Honorio, E. N., Killeen, T. J., Laurance, S. G., Laurance, W. F., Licona, J., Lovejoy, T., Malhi, Y., Marimon, B., Marimon, B. H., Matos, D. C. L., Mendoza, C., Neill, D. A., Pardo, G., Peña-Claros, M., Pitman, N. C. A., Poorter, L., Prieto, A., Ramirez-Angulo, H., Roopsind, A., Rudas, A., Salomao, R. P., Silveira, M., Stropp, J., ter Steege, H., Terborgh, J., Thomas, R., Toledo, M., Torres-Lezama, A., van der Heijden, G. M. F., Vasquez, R., Guimarães Vieira, I. C., Vilanova, E., Vos, V. A. and Baker, T. R., M. O.}, title = {Variation in stem mortality rates determines patterns of aboveground biomass in Amazonian forests: implications for dynamic global vegetation models}, journal = {Global Change Biology}, year = {2016}, pages = {1--17}, doi = {https://doi.org/10.1111/gcb.13315} } |
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Johnson, C.M., Vieira, I.C.G., Zarin, D.J., Frizano, J. and Johnson, A.H. | Carbon and nutrient storage in primary and secondary forests in eastern Amazonia | 2001 | Forest Ecology and Management Vol. 147(2-3), pp. 245-252 |
article | DOI URL |
Abstract: We compared carbon and nutrient concentrations and stocks in aboveground vegetation and soils between secondary forests (10-, 20-, and 40-year-old stands subject to repeated cycles of slash-and-burn agriculture) and a primary forest fragment in the Bragantina region of Para, Brazil. We hypothesized that repeated agricultural use would result in lower nutrient concentrations and/or stocks in the plant tissue and soils of the secondary forest stands relative to the primary forest fragment. Yet there were no significant differences in median foliar tissue concentrations of C, N, P, K, Ca, or Mg between the secondary forests and the primary forest. In woody tissue, the primary forest had a lower median Mg concentration (205 mug g(-1)) than all secondary forest plots (356-620 mug g(-1)) and a higher median N concentration (0.3%) than the 40-year-old secondary forest (0.2%). Foliar nutrient stocks were higher in the secondary forests than in the primary forest due to higher foliar biomass estimates for those plots. Aboveground woody nutrient stocks were greatest in the primary forest with the exception of Mg. Soil concentrations of exchangeable Ca decreased with increasing stand age; soil concentrations of exchangeable Mg were higher in all secondary plot soils than in the primary plot soil, Labile P stocks were greater in the primary forest soil than in all secondary forest soils. Soil labile P stocks were larger than aboveground P stocks in the 10- and 20-year-old secondary plots and the primary plot and approximately equal to aboveground stocks in the 40-year-old plot. Relative to other tropical and temperate locations, nutrient capital at these sites is low in both the vegetation and the soil, but a century of shifting cultivation does not yet appear to have introduced soil nutrient limitations to forest regrowth. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{johnson_carbon_2001, author = {Johnson, C. M. and Vieira, I. C. G. and Zarin, D. J. and Frizano, J. and Johnson, A. H.}, title = {Carbon and nutrient storage in primary and secondary forests in eastern Amazonia}, journal = {Forest Ecology and Management}, year = {2001}, volume = {147}, number = {2-3}, pages = {245--252}, url = {://WOS:000169027000010}, doi = {https://doi.org/10.1016/s0378-1127(00)00466-7} } |
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Johnson, B.T., Haywood, J.M., Langridge, J.M., Darbyshire, E., Morgan, W.T., Szpek, K., Brooke, J., Marenco, F., Coe, H., Artaxo, P., Longo, K.M., Mulcahy, J., Mann, G., Dalvi, M. and Bellouin, N. | Evaluation of biomass burning aerosols 1 in the HadGEM climate model with observations from the SAMBBA field campaign [BibTeX] |
2016 | Atmos. Chem. Phys. Discuss. | article | DOI |
BibTeX:
@article{johnson_evaluation_2016, author = {Johnson, B. T. and Haywood, J. M. and Langridge, J. M. and Darbyshire, E. and Morgan, W. T. and Szpek, K. and Brooke, J. and Marenco, F. and Coe, H. and Artaxo, P. and Longo, K. M. and Mulcahy, J. and Mann, G. and Dalvi, M. and Bellouin, N.}, title = {Evaluation of biomass burning aerosols 1 in the HadGEM climate model with observations from the SAMBBA field campaign}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2016}, doi = {https://doi.org/10.5194/acp-2016-442} } |
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John M. Melack and Javier Tomasella, R.L.V. | Surface Waters in Amazonia: Key Findings and Perspectives [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 485-488 |
incollection | |
BibTeX:
@incollection{m_keller_surface_2009, author = {John M. Melack, and Javier Tomasella, Reynaldo L. Victoria}, title = {Surface Waters in Amazonia: Key Findings and Perspectives}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {485--488} } |
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Joetzjer, E., Delire, C., Douville, H., Ciais, P., Decharme, B., Fisher, R., Christoffersen, B., Calvet, J.C., da Costa, A.C.L., Ferreira, L.V. and Meir, P. | Predicting the response of the Amazon rainforest to persistent drought conditions under current and future climates: a major challenge for global land surface models [BibTeX] |
2014 | Geoscientific model development discussions Vol. 7(4), pp. 5295-5340 |
article | DOI |
BibTeX:
@article{joetzjer_predicting_2014, author = {Joetzjer, E. and Delire, C. and Douville, H. and Ciais, P. and Decharme, B. and Fisher, R. and Christoffersen, B. and Calvet, J. C. and da Costa, A. C. L. and Ferreira, L. V. and Meir, P.}, title = {Predicting the response of the Amazon rainforest to persistent drought conditions under current and future climates: a major challenge for global land surface models}, journal = {Geoscientific model development discussions}, year = {2014}, volume = {7}, number = {4}, pages = {5295--5340}, doi = {https://doi.org/10.5194/gmdd-} } |
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Jirka, S., McDonald, A.J., Johnson, M.S., Feldpausch, T.R., Couto, E.G. and Riha, S.J. | Relationships between soil hydrology and forest structure and composition in the southern Brazilian Amazon | 2007 | Journal of Vegetation Science Vol. 18(2), pp. 183-194 |
article | DOI URL |
Abstract: Question: Is soil hydrology an important niche-based driver of biodiversity in tropical forests? More specifically, we asked whether seasonal dynamics in soil water regime contributed to vegetation partitioning into distinct forest types. Location: Tropical rain forest in northwestern Mato Grosso, Brazil. Methods: We investigated the distribution of trees and lianas textgreater= 1 cm DBH in ten transects that crossed distinct hydrological transitions. Soil water content and depth to water table were measured regularly over a 13-month period. Results: A detrended correspondence analysis (DCA) of 20 dominant species and structural attributes in 10 x 10 m subplots segregated three major forest types: (1) high-statured upland forest with intermediate stem density, (2) medium-statured forest dominated by palms, and (3) low-statured campinarana forest with high stem density. During the rainy season and transition into the dry season, distinct characteristics of the soil water regime (i.e. hydro-indicators) were closely associated with each vegetation community. Stand structural attributes and hydro-indicators were statistically different among forest types. Conclusions: Some upland species appeared intolerant of anaerobic conditions as they were not present in palm and campinarana sites, which experienced prolonged periods of saturation at the soil surface. A shallow impermeable layer restricted rooting depth in the campinarana community, which could heighten drought stress during the dry season. The only vegetation able to persist in campinarana sites were short-statured trees that appear to be well-adapted to the dual extremes of inundation and drought. | |||||
BibTeX:
@article{jirka_relationships_2007, author = {Jirka, Stefan and McDonald, Andrew J. and Johnson, Mark S. and Feldpausch, Ted R. and Couto, Eduardo G. and Riha, Susan J.}, title = {Relationships between soil hydrology and forest structure and composition in the southern Brazilian Amazon}, journal = {Journal of Vegetation Science}, year = {2007}, volume = {18}, number = {2}, pages = {183--194}, url = {://WOS:000245933100004}, doi = {https://doi.org/10.1111/j.1654-1103.2007.tb02529.x} } |
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Jipp, P.H., Nepstad, D.C., Cassel, D.K. and De Carvalho, C.R. | Deep soil moisture storage and transpiration in forests and pastures of seasonally-dry amazonia | 1998 | Climatic Change Vol. 39(2-3), pp. 395-412 |
article | DOI URL |
Abstract: To assess the impacts of land-use changes on plant-available water (PAW) and evapotranspiration (ET), volumetric water content (VWC) was measured to 8 m beneath three, adjacent ecosystems for four years (1991-1994). Estimates of PAW, ET, and deep drainage were generated for mature evergreen forest, adjacent pasture, and capoeira (second-growth forest on abandoned pasture land). PAW between 0 and 8 m depth for forest, pasture, and capoeira ranged from a low of 56, 400, and 138 mm at the end of the 1992 dry season to a high of 941, 1116, and 1021 mm during the 1994 wet season. We found significant differences in deep (4-8 m) stocks of PAW when comparing pasture with both forest types. In contrast, mature forest and capoeira PAW were not significantly different from one another at any depth during the experiment. In all three ecosystems available soil moisture from 4-8 m was depleted during the 1991 dry season by plant water uptake and was not recharged to 1991 levels until 1994 due to an intervening 2-year, El Nino Southern Oscillation event. Water balance estimates (based on measurements to 8 m) showed an average 10% decrease in ET from pasture compared to mature forest. Less than 15 years after pasture abandonment, ET in second-growth forest recovered to rates nearly equaling the mature forest rate. In seasonally dry environments annual and interannual cycles of deep soil moisture recharge and depletion influence rates of transpiration and drainage. These deep cycles are not currently incorporated in models of regional and global moisture flux. | |||||
BibTeX:
@article{jipp_deep_1998, author = {Jipp, P. H. and Nepstad, D. C. and Cassel, D. K. and De Carvalho, C. R.}, title = {Deep soil moisture storage and transpiration in forests and pastures of seasonally-dry amazonia}, journal = {Climatic Change}, year = {1998}, volume = {39}, number = {2-3}, pages = {395--412}, url = {://WOS:000075280900012}, doi = {https://doi.org/10.1023/a:1005308930871} } |
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Jimenez, E.M., Moreno, F.H., Penuela, M.C., Patino, S. and Lloyd, J. | Fine root dynamics for forests on contrasting soils in the Colombian Amazon | 2009 | Biogeosciences Vol. 6(12), pp. 2809-2827 |
article | URL |
Abstract: It has been hypothesized that as soil fertility increases, the amount of carbon allocated to below-ground production (fine roots) should decrease. To evaluate this hypothesis, we measured the standing crop fine root mass and the production of fine roots (textless 2 mm) by two methods: (1) ingrowth cores and, (2) sequential soil coring, during 2.2 years in two lowland forests growing on different soils types in the Colombian Amazon. Differences of soil resources were defined by the type and physical and chemical properties of soil: a forest on clay loam soil (Endostagnic Plinthosol) at the Amacayacu National Natural Park and, the other on white sand (Ortseinc Podzol) at the Zafire Biological Station, located in the Forest Reservation of the Calderon River. We found that the standing crop fine root mass and the production was significantly different between soil depths (0-10 and 10-20 cm) and also between forests. The loamy sand forest allocated more carbon to fine roots than the clay loam forest with the production in loamy sand forest twice (mean +/- standard error=2.98 +/- 0.36 and 3.33 +/- 0.69 Mg C ha(-1) yr(-1), method 1 and 2, respectively) as much as for the more fertile loamy soil forest (1.51 +/- 0.14, method 1, and from 1.03 +/- 0.31 to 1.36 +/- 0.23 Mg C ha(-1) yr(-1), method 2). Similarly, the average of standing crop fine root mass was higher in the white-sands forest (10.94 +/- 0.33 Mg C ha(-1)) as compared to the forest on the more fertile soil (from 3.04 +/- 0.15 to 3.64 +/- 0.18 Mg C ha(-1)). The standing crop fine root mass also showed a temporal pattern related to rainfall, with the production of fine roots decreasing substantially in the dry period of the year 2005. These results suggest that soil resources may play an important role in patterns of carbon allocation to the production of fine roots in these forests as the proportion of carbon allocated to above- and below-ground organs is different between forest types. Thus, a trade-off between above- and below-ground growth seems to exist with our results also suggesting that there are no differences in total net primary productivity between these two forests, but with higher below-ground production and lower above-ground production for the forest on the nutrient poor soil. | |||||
BibTeX:
@article{jimenez_fine_2009, author = {Jimenez, E. M. and Moreno, F. H. and Penuela, M. C. and Patino, S. and Lloyd, J.}, title = {Fine root dynamics for forests on contrasting soils in the Colombian Amazon}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {12}, pages = {2809--2827}, url = {://WOS:000273060100006} } |
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Jeong, D., Seco, R., Emmons, L., Schwantes, R., Liu, Y., McKinney, K.A., Martin, S.T., Keutsch, F.N., Gu, D., Guenther, A.B., Vega, O., Tota, J., Souza, R.A.F., Springston, S.R., Watson, T.B. and Kim, S. | Reconciling Observed and Predicted Tropical Rainforest OH Concentrations | 2022 | Journal of Geophysical Research: Atmospheres Vol. 127(1), pp. e2020JD032901 |
article | DOI URL |
Abstract: Abstract We present OH observations made in Amazonas, Brazil during the Green Ocean Amazon campaign (GoAmazon2014/5) from February to March of 2014. The average diurnal variation of OH peaked with a midday (10:00–15:00) average of 1.0 × 106 (±0.6 × 106) molecules cm−3. This was substantially lower than previously reported in other tropical forest photochemical environments (2–5 × 106 molecules cm−3) while the simulated OH reactivity was lower. The observational data set was used to constrain a box model to examine how well current photochemical reaction mechanisms can simulate observed OH. We used one near-explicit mechanism (MCM v3.3.1) and four condensed mechanisms (i.e., RACM2, MOZART-T1, CB05, CB6r2) to simulate OH. A total of 14 days of analysis shows that all five chemical mechanisms were able to explain the measured OH within instrumental uncertainty of 40% during the campaign in the Amazonian rainforest environment. Future studies are required using more reliable NOx and VOC measurements to further investigate discrepancies in our understanding of the radical chemistry in the tropical rainforest. | |||||
BibTeX:
@article{jeong_reconciling_2022, author = {Jeong, Daun and Seco, Roger and Emmons, Louisa and Schwantes, Rebecca and Liu, Yingjun and McKinney, Karena A. and Martin, Scot T. and Keutsch, Frank N. and Gu, Dasa and Guenther, Alex B. and Vega, Oscar and Tota, Julio and Souza, Rodrigo A. F. and Springston, Stephen R. and Watson, Thomas B. and Kim, Saewung}, title = {Reconciling Observed and Predicted Tropical Rainforest OH Concentrations}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2022}, volume = {127}, number = {1}, pages = {e2020JD032901}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JD032901}, doi = {https://doi.org/10.1029/2020JD032901} } |
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Jasinski, E., Morton, D., DeFries, R., Shimabukuro, Y., Anderson, L.O. and Hansen, M. | Physical landscape correlates of the expansion of mechanized agriculture in Mato Grosso, Brazil | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Mechanized agriculture is rapidly expanding in the state of Mato Grosso, Brazil. In the past five years, land area planted with soybeans, the state's principal crop, has increased at an average rate of 19.4% yr(-1). Drivers of this large-scale land-use conversion are principally economic and sociopolitical,but physical properties of the landscape make some areas more attractive than others for expansion of mechanized agriculture. The goal of this study is to evaluate several physical characteristics of land in Mato Grosso and to quantify their respective weights in determining the likelihood of land-use conversion to crop production. A 2003 land-cover classification at 250-m resolution was compared to maps of five physical landscape characteristics ( surface slope, soil type, total November precipitation, distance from paved roads, and previous land-cover type based on a 2001 classification). A land-cover transition matrix was generated to inform analysis of the role of previous land-cover type, and statewide distributions of the other four landscape characteristics were examined across agricultural and nonagricultural land. Finally, logistic regressions were performed to quantify the respective correlations of these various characteristics with the probability of conversion to mechanized agriculture. Areas of new cropland in 2003 ( converted since the 2001 classification) were nearly 3 times as likely to have been converted from pasture/cerrado as from all other land-cover types combined, but in terms of class original extent, bare soil was by far the most likely class to be converted to cropland, with 56% of its 2001 land area being converted by 2003. The physical landscape parameter found most highly correlated with conversion to mechanized agriculture between 2001 and 2003 was that of the previous land-cover type, followed by topographic slope and distance from paved roads. Soil type and total November precipitation were poorly correlated with mechanized agriculture. Findings from this study suggest that holistic, spatially explicit models of likelihood of conversion to mechanized agriculture should consider land cover, slope, and proximity to main roads in addition to political and economic parameters to generate realistic scenarios for sustainable land-use planning. | |||||
BibTeX:
@article{jasinski_physical_2005, author = {Jasinski, E. and Morton, D. and DeFries, R. and Shimabukuro, Y. and Anderson, L. O. and Hansen, M.}, title = {Physical landscape correlates of the expansion of mechanized agriculture in Mato Grosso, Brazil}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241214300001} } |
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Jardine, A., Arneth, A., Abrell, L., Jardine, A., Artaxo, P., Alves, E., Kesselmeier, J., Taylor, T., Saleska, S., Huxman T., K. and Serrano, Y. | Ecosystem-scale compensation points of formic and acetic acid in the central Amazon [BibTeX] |
2011 | Biogeosciences Vol. 8, pp. 3709-3720 |
article | |
BibTeX:
@article{jardine_ecosystem-scale_2011, author = {Jardine, A. ; Arneth, A. ; Abrell, L. ; Jardine, A. ; Artaxo, P. ; Alves, E. ; Kesselmeier, J. ; Taylor, T.; Saleska, S.; Huxman, T., K. ; Yañez Serrano}, title = {Ecosystem-scale compensation points of formic and acetic acid in the central Amazon}, journal = {Biogeosciences}, year = {2011}, volume = {8}, pages = {3709--3720} } |
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Jardine, K.J., Zorzanelli, R.F., Gimenez, B.O., Robles, E. and de Oliveira Piva, L.R. | Development of a portable leaf photosynthesis and volatile organic compounds emission system | 2020 | MethodsX Vol. 7, pp. 100880 |
article | DOI URL |
Abstract: Understanding how plant carbon metabolism responds to environmental variables such as light is central to understanding ecosystem carbon cycling and the production of food, biofuels, and biomaterials. Here, we couple a portable leaf photosynthesis system to an autosampler for volatile organic compounds (VOCs) to enable field observations of net photosynthesis simultaneously with emissions of VOCs as a function of light. Following sample collection, VOCs are analyzed using automated thermal desorption-gas chromatograph-mass spectrometry (TD-GC–MS). An example is presented from a banana plant in the central Amazon with a focus on the response of photosynthesis and the emissions of eight individual monoterpenes to light intensity. Our observations reveal that banana leaf emissions represent a 1.1 +/- 0.1% loss of photosynthesis by carbon. Monoterpene emissions from banana are dominated by trans-β-ocimene, which accounts for up to 57% of total monoterpene emissions at high light. We conclude that the developed system is ideal for the identification and quantification of VOC emissions from leaves in parallel with CO2 and water fluxes.The system therefore permits the analysis of biological and environmental sensitivities of carbon metabolism in leaves in remote field locations, resulting in the emission of hydrocarbons to the atmosphere.•A field-portable system is developed for the identification and quantification of VOCs from leaves in parallel with leaf physiological measurements including photosynthesis and transpiration.•The system will enable the characterization of carbon and energy allocation to the biosynthesis and emission of VOCs linked with photosynthesis (e.g. isoprene and monoterpenes) and their biological and environmental sensitivities (e.g. light, temperature, CO2).•Allow the development of more accurate mechanistic global VOC emission models linked with photosynthesis, improving our ability to predict how forests will respond to climate change. It is our hope that the presented system will contribute with critical data towards these goals across Earth's diverse tropical forests. | |||||
BibTeX:
@article{jardine_development_2020, author = {Jardine, Kolby J. and Zorzanelli, Raquel F. and Gimenez, Bruno O. and Robles, Emily and de Oliveira Piva, Luani Rosa}, title = {Development of a portable leaf photosynthesis and volatile organic compounds emission system}, journal = {MethodsX}, year = {2020}, volume = {7}, pages = {100880}, url = {https://www.sciencedirect.com/science/article/pii/S2215016120300996}, doi = {https://doi.org/10.1016/j.mex.2020.100880} } |
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Jardine, K.J., Zorzanelli, R.F., Gimenez, B.O., Oliveira Piva, L.R.d., Teixeira, A., Fontes, C.G., Robles, E., Higuchi, N., Chambers, J.Q. and Martin, S.T. | Leaf isoprene and monoterpene emission distribution across hyperdominant tree genera in the Amazon basin | 2020 | Phytochemistry Vol. 175, pp. 112366 |
article | DOI URL |
Abstract: Tropical forests are acknowledged to be the largest global source of isoprene (C5H8) and monoterpenes (C10H16) emissions, with current synthesis studies suggesting few tropical species emit isoprenoids (20–38%) and do so with highly variable emission capacities, including within the same genera. This apparent lack of a clear phylogenetic thread has created difficulties both in linking isoprenoid function with evolution and for the development of accurate biosphere-atmosphere models. Here, we present a systematic emission study of “hyperdominant” tree species in the Amazon Basin. Across 162 individuals, distributed among 25 botanical families and 113 species, isoprenoid emissions were widespread among both early and late successional species (isoprene: 61.9% of the species; monoterpenes: 15.0%; both isoprene and monoterpenes: 9.7%). The hyperdominant species (69) across the top five most abundant genera, which make up about 50% of all individuals in the Basin, had a similar abundance of isoprenoid emitters (isoprene: 63.8%; monoterpenes: 17.4%; both 11.6%). Among the abundant genera, only Pouteria had a low frequency of isoprene emitting species (15.8% of 19 species). In contrast, Protium, Licania, Inga, and Eschweilera were rich in isoprene emitting species (83.3% of 12 species, 61.1% of 18 species, 100% of 8 species, and 100% of 12 species, respectively). Light response curves of individuals in each of the five genera showed light-dependent, photosynthesis-linked emission rates of isoprene and monoterpenes. Importantly, in every genus, we observed species with light-dependent isoprene emissions together with monoterpenes including β-ocimene. These observations support the emerging view of the evolution of isoprene synthases from β-ocimene synthases. Our results have important implications for understanding isoprenoid function-evolution relationships and the development of more accurate Earth System Models. | |||||
BibTeX:
@article{jardine_leaf_2020, author = {Jardine, Kolby J. and Zorzanelli, Raquel F. and Gimenez, Bruno O. and Oliveira Piva, Luani Rosa de and Teixeira, Andrea and Fontes, Clarissa G. and Robles, Emily and Higuchi, Niro and Chambers, Jeffrey Q. and Martin, Scot T.}, title = {Leaf isoprene and monoterpene emission distribution across hyperdominant tree genera in the Amazon basin}, journal = {Phytochemistry}, year = {2020}, volume = {175}, pages = {112366}, url = {https://www.sciencedirect.com/science/article/pii/S0031942219310994}, doi = {https://doi.org/10.1016/j.phytochem.2020.112366} } |
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Jardine, K.J., Sommer, E.D., Saleska, S.R., Huxman, T.E., Harley, P.C. and Abrell, L. | Gas Phase Measurements of Pyruvic Acid and Its Volatile Metabolites | 2010 | Environmental Science & Technology Vol. 44(7), pp. 2454-2460 |
article | DOI URL |
Abstract: Pyruvic acid, central to leaf carbon metabolism, is a precursor of many volatile organic compounds (VOCs) that impact air quality and climate. Although the pathways involved in the production of isoprenoids are well-known, those of several oxygenated VOCs remain uncertain. We present concentration and flux measurements of pyruvic acid and other VOCs within the tropical rainforest (TRF) biome at Biosphere 2. Pyruvic acid concentrations varied diurnally with midday maxima up to 15 ppbv, perhaps due to enhanced production rates and suppression of mitochondrial respiration in the light Branch fluxes and ambient concentrations of pyruvic acid correlated with those of acetone, acetaldehyde, ethanol, acetic acid, isoprene, monoterpenes, and sesquiterpenes. While pyruvic acid is a known substrate for isoprenoid synthesis, this correlation suggests that the oxygenated VOCs may also derive from pyruvic acid, an idea supported by leaf feeding experiments with sodium pyruvate which resulted in large enhancements in emissions of both isoprenoids and oxygenated VOCs. While feeding with sodium pyruvate-2-(13)C resulted in large emissions of both (13)C-labeled isoprenoids and oxygenated VOCs, feeding with sodium pyruvate-1-(13)C resulted in only (13)C-labeled isoprenoids. This suggests that acetaldehyde, ethanol, and acetic acid are produced from pyruvic acid via the pyruvate dehydrogenase (PDH) bypass system (in which the 1-C carbon of pyruvic acid is lost as CO(2)) and that acetone is also derived from the decarboxylation of pyruvic acid. | |||||
BibTeX:
@article{jardine_gas_2010, author = {Jardine, Kolby J. and Sommer, Evan D. and Saleska, Scott R. and Huxman, Travis E. and Harley, Peter C. and Abrell, Leif}, title = {Gas Phase Measurements of Pyruvic Acid and Its Volatile Metabolites}, journal = {Environmental Science & Technology}, year = {2010}, volume = {44}, number = {7}, pages = {2454--2460}, note = {Edition: 2010/03/10}, url = {://WOS:000275993700037}, doi = {https://doi.org/10.1021/es903544p} } |
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Jardine, K.J., Jardine, A.B., Souza, V.F., Carneiro, V., Ceron, J.V., Gimenez, B.O., Soares, C.P., Durgante, F.M., Higuchi, N., Manzi, A.O., Gonçalves, J.F.C., Garcia, S., Martin, S.T., Zorzanelli, R.F., Piva, L.R. and Chambers, J.Q. | Methanol and isoprene emissions from the fast growing tropical pioneer species Vismia guianensis (Aubl.) Pers. (Hypericaceae) in the central Amazon forest [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 6441-6452 |
article | DOI |
BibTeX:
@article{jardine_methanol_2016, author = {Jardine, Kolby J. and Jardine, Angela B. and Souza, Vinicius F. and Carneiro, Vilany and Ceron, Joao V. and Gimenez, Bruno O. and Soares, Cilene P. and Durgante, Flavia M. and Higuchi, Niro and Manzi, Antonio O. and Gonçalves, José F. C. and Garcia, Sabrina and Martin, Scot T. and Zorzanelli, Raquel F. and Piva, Luani R. and Chambers, Jeff Q.}, title = {Methanol and isoprene emissions from the fast growing tropical pioneer species Vismia guianensis (Aubl.) Pers. (Hypericaceae) in the central Amazon forest}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {6441--6452}, doi = {https://doi.org/10.5194/acp-16-6441-2016} } |
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Jardine, K.J., Jardine, A.B., Holm, J.A., Lombardozzi, D.L., Negron-Juarez, R.I., Martin, S.T., Beller, H.R., Gimenez, B.O., Higuchi, N. and Chambers, J.Q. | Monoterpene ‘thermometer’ of tropical forest-atmosphere response to climate warming [BibTeX] |
2017 | Plant, Cell & Environment Vol. 40, pp. 441-452 |
article | DOI |
BibTeX:
@article{jardine_monoterpene_2017, author = {Jardine, K. J. and Jardine, A. B. and Holm, J. A. and Lombardozzi, D. L. and Negron-Juarez, R. I. and Martin, S. T. and Beller, H. R. and Gimenez, B. O. and Higuchi, N. and Chambers, J. Q.}, title = {Monoterpene ‘thermometer’ of tropical forest-atmosphere response to climate warming}, journal = {Plant, Cell & Environment}, year = {2017}, volume = {40}, pages = {441--452}, doi = {https://doi.org/10.1111/pce.12879} } |
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Jardine, K., Fernandes de Souza, V., Oikawa, P., Higuchi, N., Bill, M., Porras, R., Niinemets, Ü. and Chambers, J. | Integration of C1 and C2 Metabolism in Trees [BibTeX] |
2017 | Int. J. Mol. Sci. Vol. 18(10), pp. 2045 |
article | |
BibTeX:
@article{jardine_integration_2017, author = {Jardine, K.J. and Fernandes de Souza, V. and Oikawa, P. and Higuchi, N. and Bill, M. and Porras, R. and Niinemets, Ü and Chambers, J.Q.}, title = {Integration of C1 and C2 Metabolism in Trees}, journal = {Int. J. Mol. Sci.}, year = {2017}, volume = {18}, number = {10}, pages = {2045} } |
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Jardine, K.J., de O. Piva, L.R., Rodrigues, T.B., Spanner, G.C., Rodrigues, J.R., Menezes, V.S., Sampaio, I., Oliveira, D.C., Gimenez, B.O., Higuchi, N. and Chambers, J. | Volatiles defenses of Amazon Azteca ants (repellent ants) | 2020 | BioRxiv, pp. 2020.04.15.043547 | article | DOI URL |
Abstract: Azteca ants are widely distributed in the neotropics and have been utilized as natural insect repellent for centuries. Azteca oils provide natural defense against herbivores in mutualistic interactions between ants and their host trees. While chemical characterization of oil secretions revealed a composition dominated by iridoids and ketones, the volatile emissions from Azteca ants, and therefore the active gas-phase semiochemicals, remain uncharacterized. In this study, we determined the composition of volatile emissions from a sample of an Azteca ant nest near the Rio Negro in the central Amazon. We found Azteca emissions were composed of a blend of methyl cyclopentyl and methyl cyclopentenyl based volatiles previously identified in Azteca oil extracts as potent alarm pheromones. The ketone 6-methyl-5-hepten-2-one, which also waspreviously identified as a major component of the Azteca oil, was found to be the dominant volatile emitted. For the first time, we report emissions of the highly volatile ketones 2,3-butadione and acetoin from the Azteca nest. Our study has important implications for the better understanding of the ecology and defense strategies of Azteca ants in herbivore defense and provides a base for future commercial applications involving Azteca ant essential oils as natural insect repellents.Competing Interest StatementThe authors have declared no competing interest. | |||||
BibTeX:
@article{jardine_volatiles_2020, author = {Jardine, Kolby J. and de O. Piva, Luani R. and Rodrigues, Tayana B. and Spanner, Gustavo C. and Rodrigues, Jardel R. and Menezes, Valdiek S. and Sampaio, Israel and Oliveira, Daniela C. and Gimenez, Brunon O. and Higuchi, Niro and Chambers, Jeffrey}, title = {Volatiles defenses of Amazon Azteca ants (repellent ants)}, journal = {BioRxiv}, year = {2020}, pages = {2020.04.15.043547}, url = {http://biorxiv.org/content/early/2020/04/17/2020.04.15.043547.abstract}, doi = {https://doi.org/10.1101/2020.04.15.043547} } |
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Jardine, K.J., Cobello, L.O., Teixeira, L.M., East, M.-M.S., Levine, S., Gimenez, B.O., Robles, E., Spanner, G., Koven, C., Xu, C., Warren, J.M., Higuchi, N., McDowell, N., Pastorello, G. and Chambers, J.Q. | Stem respiration and growth in a central Amazon rainforest | 2022 | Trees Vol. 36(3), pp. 991-1004 |
article | DOI URL |
Abstract: Annual stem CO2 efflux increases with stem wood production rates and are inhibited by daily moisture stress. | |||||
BibTeX:
@article{jardine_stem_2022, author = {Jardine, Kolby J. and Cobello, Leticia O. and Teixeira, Liliane M. and East, Malyia-Mason S. and Levine, Sienna and Gimenez, Bruno O. and Robles, Emily and Spanner, Gustavo and Koven, Charlie and Xu, Chongang and Warren, Jeffrey M. and Higuchi, Niro and McDowell, Nate and Pastorello, Gilberto and Chambers, Jeffrey Q.}, title = {Stem respiration and growth in a central Amazon rainforest}, journal = {Trees}, year = {2022}, volume = {36}, number = {3}, pages = {991--1004}, url = {https://doi.org/10.1007/s00468-022-02265-5}, doi = {https://doi.org/10.1007/s00468-022-02265-5} } |
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Jardine, K.J., Chambers, J.Q., Holm, J., Jardine, A.B., Fontes, C.G., Zorzanelli, R.F., Meyers, K.T., Souza, V.F.d., Garcia, S., Gimenez, B.O., Piva, L.R.d.O., Higuchi, N., Artaxo, P., Martin, S. and Manzi, A.O. | Green Leaf Volatile Emissions during High Temperature and Drought Stress in a Central Amazon Rainforest [BibTeX] |
2015 | Plants Vol. 4(3), pp. 678 - 690 |
article | DOI |
BibTeX:
@article{jardine_green_2015, author = {Jardine, Kolby J. and Chambers, J. Q. and Holm, J. and Jardine, A. B. and Fontes, C. G. and Zorzanelli, R. F. and Meyers, K. T. and Souza, V. F. de and Garcia, S. and Gimenez, B. O. and Piva, L. R. de O. and Higuchi, N. and Artaxo, P. and Martin, S. and Manzi, A. O.}, title = {Green Leaf Volatile Emissions during High Temperature and Drought Stress in a Central Amazon Rainforest}, journal = {Plants}, year = {2015}, volume = {4}, number = {3}, pages = {678 -- 690}, note = {Edition: http://www.mdpi.com/2223-7747/4/3/678}, doi = {https://doi.org/10.3390/plants4030678} } |
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Jardine, K., Russell K, ., Monson, R., Abrell, L., Saleska, S., Arneth, A., Jardine, A., Ishida, F., Serrano, A., Artaxo, P., Karl, T., Fares, S., Goldstein, A., Loreto, F. and Huxman, T. | Within-plant isoprene oxidation confirmed by direct emissions of oxidation products methyl vinyl ketone and methacrolein [BibTeX] |
2012 | Global Change Biology Vol. 18, Issue, pg.(3), pp. 973-984 |
article | DOI |
BibTeX:
@article{jardine_within-plant_2012, author = {Jardine, K.J. and ., Russell K and Monson, R.K. and Abrell, L. and Saleska, S.R. and Arneth, A. and Jardine, A. and Ishida, F.Y. and Serrano, A.M.Y. and Artaxo, P. and Karl, T. and Fares, S. and Goldstein, A. and Loreto, F. and Huxman, T.}, title = {Within-plant isoprene oxidation confirmed by direct emissions of oxidation products methyl vinyl ketone and methacrolein}, journal = {Global Change Biology}, year = {2012}, volume = {18, Issue, pg.}, number = {3}, pages = {973--984}, doi = {https://doi.org/10.1111/j.1365-2486.2011.02610.x} } |
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Jardine, K., Yañez-Serrano, A.M., Williams, J., Kunert, N., Jardine, A., Taylor, T., Abrell, l., Artaxo, P., Guenther, A., Hewitt, C.N., House, E., Florentino, A.P., Manzi, A., Higuchi, N., Kesselmeier, J., Behrendt, T., Veres, P.R., Derstroff, B., Fuentes, J.D., Martin, S.T. and Andreae, M.O. | Dimethyl sulfide in the Amazon rain forest [BibTeX] |
2015 | Global Biogeochemical Cycles Vol. 29 |
article | |
BibTeX:
@article{jardine_dimethyl_2015, author = {Jardine, K. and Yañez-Serrano, A. M. and Williams, J. and Kunert, N. and Jardine, A. and Taylor, T. and Abrell, l. and Artaxo, P. and Guenther, A. and Hewitt, C. N. and House, E. and Florentino, A. P. and Manzi, A.O. and Higuchi, N. and Kesselmeier, J. and Behrendt, T. and Veres, P. R. and Derstroff, B. and Fuentes, J. D. and Martin, S. T. and Andreae, M. O.}, title = {Dimethyl sulfide in the Amazon rain forest}, journal = {Global Biogeochemical Cycles}, year = {2015}, volume = {29} } |
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Jardine, K., Serrano, A.Y., Arneth, A., Abrell, L., Jardine, A., van Haren, J., Artaxo, P., Rizzo, L.V., Ishida, F.Y., Karl, T., Kesselmeier, J., Saleska, S. and Huxman, T. | Within-canopy sesquiterpene ozonolysis in Amazonia | 2011 | Journal of Geophysical Research-Atmospheres Vol. 116 |
article | DOI URL |
Abstract: Through rapid reactions with ozone, which can initiate the formation of secondary organic aerosols, the emission of sesquiterpenes from vegetation in Amazonia may have significant impacts on tropospheric chemistry and climate. Little is known, however, about sesquiterpene emissions, transport, and chemistry within plant canopies owing to analytical difficulties stemming from very low ambient concentrations, high reactivities, and sampling losses. Here, we present ambient sesquiterpene concentration measurements obtained during the 2010 dry season within and above a primary tropical forest canopy in Amazonia. We show that by peaking at night instead of during the day, and near the ground instead of within the canopy, sesquiterpene concentrations followed a pattern different from that of monoterpenes, suggesting that unlike monoterpene emissions, which are mainly light dependent, sesquiterpene emissions are mainly temperature dependent. In addition, we observed that sesquiterpene concentrations were inversely related with ozone (with respect to time of day and vertical concentration), suggesting that ambient concentrations are highly sensitive to ozone. These conclusions are supported by experiments in a tropical rain forest mesocosm, where little atmospheric oxidation occurs and sesquiterpene and monoterpene concentrations followed similar diurnal patterns. We estimate that the daytime dry season ozone flux of -0.6 to -1.5 nmol m(-2) s(-1) due to in-canopy sesquiterpene reactivity could account for 7%-28% of the net ozone flux. Our study provides experimental evidence that a large fraction of total plant sesquiterpene emissions (46%-61% by mass) undergo within-canopy ozonolysis, which may benefit plants by reducing ozone uptake and its associated oxidative damage. | |||||
BibTeX:
@article{jardine_within-canopy_2011, author = {Jardine, K. and Serrano, A. Yanez and Arneth, A. and Abrell, L. and Jardine, A. and van Haren, J. and Artaxo, P. and Rizzo, L. V. and Ishida, F. Y. and Karl, T. and Kesselmeier, J. and Saleska, S. and Huxman, T.}, title = {Within-canopy sesquiterpene ozonolysis in Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2011}, volume = {116}, url = {://WOS:000295536400002}, doi = {https://doi.org/10.1029/2011jd016243} } |
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Jardine, K. and Jardine, A. | Biogenic Volatile Organic Compounds in Amazonian Forest Ecosystems [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 19-33 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_biogenic_2016, author = {Jardine, Kolby and Jardine, Angela}, title = {Biogenic Volatile Organic Compounds in Amazonian Forest Ecosystems}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {19--33}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Jardine, K., Chambers, J., Alves, E.G., Teixeira, A., Garcia, S., Holm, J., Higuchi, N., Manzi, A., Abrell, L., Fuentes, J.D., Nielsen, L.K., Torn, M. and Vickers, C... | Dynamic balancing of isoprene carbon sources reflects photosynthetic and photorespiratory responses to temperature stress [BibTeX] |
2014 | Plant Physiology (Bethesda) Vol. 166, pp. 2051-2064 |
article | |
BibTeX:
@article{jardine_dynamic_2014, author = {Jardine, K. and Chambers, J. and Alves, E. G. and Teixeira, A. and Garcia, S. and Holm, J. and Higuchi, N. and Manzi, A. and Abrell, L. and Fuentes, J. D. and Nielsen, L. K. and Torn, M. and Vickers, C. .}, title = {Dynamic balancing of isoprene carbon sources reflects photosynthetic and photorespiratory responses to temperature stress}, journal = {Plant Physiology (Bethesda)}, year = {2014}, volume = {166}, pages = {2051--2064} } |
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Jardine, A., Jardine, K., Fuentes, J., Martin, S., Martins, G., Durgante, F., Carneiro, V., Higushi, N., Manzi, A. and Chambers, J. | Highly reactive light-dependent monoterpenes in the Amazon [BibTeX] |
2015 | Geophysical Research Letters Vol. 42, pp. 1576-1583 |
article | |
BibTeX:
@article{jardine_highly_2015, author = {Jardine, A. and Jardine, K. and Fuentes, J. and Martin, S. and Martins, G. and Durgante, F. and Carneiro, V. and Higushi, N. and Manzi, A.O. and Chambers, J.}, title = {Highly reactive light-dependent monoterpenes in the Amazon}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, pages = {1576--1583} } |
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Jaquetti, J.F.d., Silva Ferraz, J.B., Ferreira, M.J., Santos Junior, U.M.d., Lacerda Claudivan Feitosa de, R.K. and Gonçalves, C. | Green Fertilization Enhances the Photosynthetic Performance and the Growth of Leguminous Trees for Restoration Plantation in Central Amazon [BibTeX] |
2014 | American Journal of Plant Sciences Vol. 05, pp. 2497-2508 |
article | |
BibTeX:
@article{jaquetti_green_2014, author = {Jaquetti, José Francisco de ; Silva Ferraz, João Baptista ; Ferreira, Marciel J. ; Santos Junior, Ulysses Moreira dos ; Lacerda, Claudivan Feitosa de, Roberto Kirmayr ; Carvalho Gonçalves}, title = {Green Fertilization Enhances the Photosynthetic Performance and the Growth of Leguminous Trees for Restoration Plantation in Central Amazon}, journal = {American Journal of Plant Sciences}, year = {2014}, volume = {05}, pages = {2497--2508} } |
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Janhaell, S., Andreae, M.O. and Poeschl, U. | Biomass burning aerosol emissions from vegetation fires: particle number and mass emission factors and size distributions | 2010 | Atmospheric Chemistry and Physics Vol. 10(3), pp. 1427-1439 |
article | URL |
Abstract: Aerosol emissions from vegetation fires have a large impact on air quality and climate. In this study, we use published experimental data and different fitting procedures to derive dynamic particle number and mass emission factors (EF(PN), EF(PM)) related to the fuel type, burning conditions and the mass of dry fuel burned, as well as characteristic CO-referenced emission ratios (PN/CO, PM/CO). Moreover, we explore and characterize the variability of the particle size distribution of fresh smoke, which is typically dominated by a lognormal accumulation mode with count median diameter around 120 nm (depending on age, fuel and combustion efficiency), and its effect on the relationship between particle number and mass emission factors. For the particle number emission factor of vegetation fires, we found no dependence on fuel type and obtained the following parameterization as a function of modified combustion efficiency (MCE): EF(PN) = 34 x 10(15) x (1-MCE) kg(-1) +/- 10(15) kg(-1) with regard to dry fuel mass (d.m.). For the fine particle mass emission factors (EF(PM)) we obtained (86 - 85 x MCE) g kg(-1) +/- 3 g kg(-1) as an average for all investigated fires; (93 - 90 x MCE) g kg(-1) +/- 4 g kg(-1) for forest; (67 - 65 x MCE) g kg(-1) +/- 2 g kg(-1) for savanna; (63 - 62 x MCE) g kg(-1) +/- 1 g kg(-1) for grass. For the PN/CO emission ratio we obtained an average of (34 +/- 16) cm(-3) ppb(-1) exhibiting no systematic dependence on fuel type or combustion efficiency. The average PM/CO emission ratios were (0.09 +/- 0.04) g g(-1) for all investigated fires; (0.13 +/- 0.05) g g(-1) for forest; (0.08 +/- 0.03) g g(-1) for savanna; and (0.07 +/- 0.03) g g(-1) for grass. The results are consistent with each other, given that particles from forest fires are on average larger than those from savanna and grass fires. This assumption and the above parameterizations represent the current state of knowledge, but they are based on a rather limited amount of experimental data which should be complemented by further measurements. Nevertheless, the presented parameterizations appear sufficiently robust for exploring the influence of vegetation fires on aerosol particle number and mass concentrations in regional and global model studies. | |||||
BibTeX:
@article{janhaell_biomass_2010, author = {Janhaell, S. and Andreae, M. O. and Poeschl, U.}, title = {Biomass burning aerosol emissions from vegetation fires: particle number and mass emission factors and size distributions}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {3}, pages = {1427--1439}, url = {://WOS:000274410000038} } |
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Jakovac, A.C., Bentos, T.V., Mesquita, R.C. and Williamson, G.B. | Age and light effects on seedling growth in two alternative secondary successions in central Amazonia [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 349-358 |
article | |
BibTeX:
@article{jakovac_age_2014, author = {Jakovac, Ana C.C. and Bentos, Tony V. and Mesquita, Rita C.G. and Williamson, G. Bruce}, title = {Age and light effects on seedling growth in two alternative secondary successions in central Amazonia}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {349--358} } |
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Jacobson, L.V., Hacon, S., Ignotti, E., Castro, H., Artaxo, P. and de Leon, A.P. | Schoolchildren Panel Study of Air Pollution from Biomass Burning in Amazon: Results by Gender and Age [BibTeX] |
2009 | Epidemiology Vol. 20(6), pp. S220-S221 |
article | URL |
BibTeX:
@article{jacobson_schoolchildren_2009, author = {Jacobson, Ludmilla Viana and Hacon, Sandra and Ignotti, Eliane and Castro, Hermano and Artaxo, Paulo and de Leon, Antonio Ponce}, title = {Schoolchildren Panel Study of Air Pollution from Biomass Burning in Amazon: Results by Gender and Age}, journal = {Epidemiology}, year = {2009}, volume = {20}, number = {6}, pages = {S220--S221}, url = {://WOS:000270874101322} } |
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Jacobson, L.V., Hacon, S., Ignotti, E., Castio, H., Artaxo, P. and de Leon, A.P. | Effects of Air Pollution from Biomass Burning in Amazon: A Panel Study of Schoolchildren [BibTeX] |
2009 | Epidemiology Vol. 20(6), pp. S90-S90 |
article | URL |
BibTeX:
@article{jacobson_effects_2009, author = {Jacobson, Ludmilla Viana and Hacon, Sandra and Ignotti, Eliane and Castio, Hermano and Artaxo, Paulo and de Leon, Antonio Ponce}, title = {Effects of Air Pollution from Biomass Burning in Amazon: A Panel Study of Schoolchildren}, journal = {Epidemiology}, year = {2009}, volume = {20}, number = {6}, pages = {S90--S90}, url = {://WOS:000270874100241} } |
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Jacobson Sandra de Souza Hacon, H.A.d.C.E.I.P.A.A.C.M.P.d.L.L.d.S.V. | Association between fine particulate matter and the peak expiratory flow of schoolchildren in the Brazilian subequatorial Amazon: A panel study. [BibTeX] |
2012 | Environmental Research Vol. 117, pp. 27-35 |
article | DOI |
BibTeX:
@article{jacobson_association_2012, author = {Jacobson, Sandra de Souza Hacon, Hermano Albuquerque de Castro, Eliane Ignotti, Paulo Artaxo, Antonio Carlos Monteiro Ponce de Leon., Ludmilla da Silva Viana}, title = {Association between fine particulate matter and the peak expiratory flow of schoolchildren in the Brazilian subequatorial Amazon: A panel study.}, journal = {Environmental Research}, year = {2012}, volume = {117}, pages = {27--35}, doi = {https://doi.org/10.1016/j.envres.2012.05.006} } |
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Jacobi, P.R., Grandisoli, E., Coutinho, S.M.V., Maia, R.d.A. and Toledo, R.F.d. | Temas atuais em mudanças climáticas: para os ensinos fundamental e médio [BibTeX] |
2015 | Vol. 1(1) |
book | |
BibTeX:
@book{jacobi_temas_2015, author = {Jacobi, Pedro Roberto and Grandisoli, Edson and Coutinho, Sonia Maria Viggiani and Maia, Roberta de Assis and Toledo, Renata Ferraz de}, title = {Temas atuais em mudanças climáticas: para os ensinos fundamental e médio}, publisher = {IEE - USP}, year = {2015}, volume = {1}, number = {1} } |
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Iwata, H., Malhi, Y. and von Randow, C. | Gap-filling measurements of carbon dioxide storage in tropical rainforest canopy airspace | 2005 | Agricultural and Forest Meteorology Vol. 132(3-4), pp. 305-314 |
article | DOI URL |
Abstract: For the determination of biotic fluxes of carbon dioxide (CO2) or other trace gases to or from a forest canopy, it is important to measure the storage of the trace gas within the forest canopy in addition to the net vertical flux above the forest canopy. However, the data continuity of within-canopy storage measurements can be poor because these measurements are subject to frequent equipment breakdowns. We here explore methods for gap-filling within-canopy CO2 storage, using the data derived from an Amazonian rainforest (Caxiuana). Our first approach was to estimate hourly storage from hourly CO2 concentration measured above the canopy at the tower top. This proved unreliable, since at this hourly time scale the variations in above-canopy CO2 are often decoupled from local changes in within-canopy storage. We then explored a second approach based on determination of the total CO2 accumulation over a night. This was found to be adequately correlated with a time-weighted friction velocity (u(*w)) averaged over a night (R-2 = 0.42). The total night-time storage was then used to model daytime depletion Of CO2 within the canopy. The gap-filling model was validated against independent data from the same site, and also applied to another tropical forest (Jaru) with similar results. The modelled storage is in good agreement with the measured storage, and by reducing susceptibility to advection error it is in some ways superior to the direct storage measurements. This suggests at the possibility of a general method for estimating storage in forest canopies, with re-calibration for each site. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{iwata_gap-filling_2005, author = {Iwata, H. and Malhi, Y. and von Randow, C.}, title = {Gap-filling measurements of carbon dioxide storage in tropical rainforest canopy airspace}, journal = {Agricultural and Forest Meteorology}, year = {2005}, volume = {132}, number = {3-4}, pages = {305--314}, url = {://WOS:000233309300011}, doi = {https://doi.org/10.1016/j.agrformet.2005.08.005} } |
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Ivanov, V.Y., Hutyra, L.R., Wofsy, S.C., Munger, J.W., Saleska, S.R., Oliveira Jr., R.C.d. and Camargo, P.B.d. | Root niche separation can explain avoidance of seasonal drought stress and vulnerability of overstory trees to extended drought in a mature Amazonian forest [BibTeX] |
2012 | Water Resources Research Vol. 48(12), pp. 121 |
article | |
BibTeX:
@article{ivanov_root_2012, author = {Ivanov, Valeriy Y. and Hutyra, Lucy R. and Wofsy, Steven C. and Munger, J. William and Saleska, Scott R. and Oliveira Jr., Raimundo C. de and Camargo, Plínio B. de}, title = {Root niche separation can explain avoidance of seasonal drought stress and vulnerability of overstory trees to extended drought in a mature Amazonian forest}, journal = {Water Resources Research}, year = {2012}, volume = {48}, number = {12}, pages = {121} } |
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Isaacman-Vanwertz, L.D., Kreisberg, N.M., Wernis, R., Moss, J.A., Hering, S.V., De Sa, S.S., Martin, S.T., Alexander, L.M., Palm, B.B., Hu, W., Campuzano-Jost, P., Day, D.A., Jimenez, J.L., Riva, M., Surratt, J.D., Viegas, J., Manzi, A., Edgerton, E.S., Baumann, K., Souza, R., Artaxo, P., Goldstein Allen H., G. and Yee | Ambient gas-particle partitioning of tracers for biogenic oxidation [BibTeX] |
2016 | Environmental Science & Technology Vol. 50(18), pp. 9952-62 |
article | DOI |
BibTeX:
@article{isaacman-vanwertz_ambient_2016, author = {Isaacman-Vanwertz, Lindsay D. ; Kreisberg, Nathan M ; Wernis, Rebecca ; Moss, Joshua A ; Hering, Susanne V ; De Sa, Suzane S ; Martin, Scot T. ; Alexander, Lizabeth M. ; Palm, Brett B ; Hu, Weiwei ; Campuzano-Jost, PEdro ; Day, Douglas A. ; Jimenez, Jose Luis ; Riva, Matthieu ; Surratt, Jason Douglas ; Viegas, Juarez ; Manzi, Antonio ; Edgerton, Eric S. ; Baumann, Karsten ; Souza, Rodrigo ; Artaxo, Paulo ; Goldstein, Allen H., Gabriel ; Yee}, title = {Ambient gas-particle partitioning of tracers for biogenic oxidation}, journal = {Environmental Science & Technology}, year = {2016}, volume = {50}, number = {18}, pages = {9952--62}, doi = {https://doi.org/10.1021/acs.est.6b01674} } |
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Ignotti, E., Valente, J.G., Longo, K.M., Freitas, S.R., Hacon, S.d.S. and Netto, P.A. | Impact on human health of particulate matter emitted from burnings in the Brazilian Amazon region | 2010 | Revista De Saude Publica Vol. 44(1), pp. 121-130 |
article | DOI URL |
Abstract: OBJECTIVE: To analyze the impact on human health of exposure to particulate matter emitted from burnings in the Brazilian Amazon region. METHODS: This was an ecological study using an environmental exposure indicator presented as the percentage of annual hours (AH%) of PM(2.5) above 80 mu g/m(3). The outcome variables were the rates of hospitalization due to respiratory disease among children, the elderly and the intermediate age group, and due to childbirth. Data were obtained from the National Space Research Institute and the Ministry of Health for all of the microregions of the Brazilian Amazon region, for the years 2004 and 2005. Multiple regression models for the outcome variables in relation to the predictive variable AH% of PM(2.5) above 80 mu g/m(3) were analyzed. The Human Development Index (HDI) and mean number of complete blood counts per 100 inhabitants in the Brazilian Amazon region were the control variables in the regression analyses. RESULTS: The association of the exposure indicator (AH%) was higher for the elderly than for other age groups (beta = 0.10). For each 1% increase in the exposure indicator there was an increase of 8% in child hospitalization, 10% in hospitalization of the elderly, and 5% for the intermediate age group, even after controlling for HDI and mean number of complete blood counts. No association was found between the AH% and hospitalization due to childbirth. CONCLUSIONS: The indicator of atmospheric pollution showed an association with occurrences of respiratory diseases in the Brazilian Amazon region, especially in the more vulnerable age groups. This indicator may be used to assess the effects of forest burning on human health. | |||||
BibTeX:
@article{ignotti_impact_2010, author = {Ignotti, Eliane and Valente, Joaquim Goncalves and Longo, Karla Maria and Freitas, Saulo Ribeiro and Hacon, Sandra de Souza and Netto, Paulo Artaxo}, title = {Impact on human health of particulate matter emitted from burnings in the Brazilian Amazon region}, journal = {Revista De Saude Publica}, year = {2010}, volume = {44}, number = {1}, pages = {121--130}, note = {Edition: 2010/02/09}, url = {://WOS:000274414300013}, doi = {https://doi.org/10.1590/s0034-89102010000100013} } |
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Ignotti, E., Junger, W., Hacon, S., Longo, K., Artaxo, P. and de Leon, A.P. | Effects of the Humidity on Hospital Admissions by Respiratory Diseases in the Subequatorial Amazon [BibTeX] |
2009 | Epidemiology Vol. 20(6), pp. S219-S219 |
article | URL |
BibTeX:
@article{ignotti_effects_2009, author = {Ignotti, Eliane and Junger, Washington and Hacon, Sandra and Longo, Karla and Artaxo, Paulo and de Leon, Antonio Ponce}, title = {Effects of the Humidity on Hospital Admissions by Respiratory Diseases in the Subequatorial Amazon}, journal = {Epidemiology}, year = {2009}, volume = {20}, number = {6}, pages = {S219--S219}, url = {://WOS:000270874101316} } |
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Ignotti, E., Junger, W., Hacon, S., Artaxo, P., Longo, K. and de Leon, A.P. | Effects of the Climate Change on Hospital Admissions by Respiratory Diseases in the Subequatorial Amazon [BibTeX] |
2009 | Epidemiology Vol. 20(6), pp. S88-S88 |
article | URL |
BibTeX:
@article{ignotti_effects_2009-1, author = {Ignotti, Eliane and Junger, Washington and Hacon, Sandra and Artaxo, Paulo and Longo, Karla and de Leon, Antonio Ponce}, title = {Effects of the Climate Change on Hospital Admissions by Respiratory Diseases in the Subequatorial Amazon}, journal = {Epidemiology}, year = {2009}, volume = {20}, number = {6}, pages = {S88--S88}, url = {://WOS:000270874100233} } |
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Ignotti, E., Hacon, S.d.S., Junger, W.L., Mourao, D., Longo, K., Freitas, S., Artaxo, P. and Monteiro Ponce de Leon, A.C. | Air pollution and hospital admissions for respiratory diseases in the subequatorial Amazon: a time series approach | 2010 | Cadernos De Saude Publica Vol. 26(4), pp. 747-761 |
article | DOI URL |
Abstract: The objective of the study is to evaluate the effect of the daily variation in concentrations of fine particulate matter (diameter less than 2.5 mu m - PM(2.5)) resulting from the burning of biomass on the daily number of hospitalizations of children and elderly people for respiratory diseases, in Alta Floresta and Tangara da Serra in the Brazilian Amazon in 2005. This is an ecological time series study that uses data on daily number of hospitalizations of children and the elderly for respiratory diseases, and estimated concentration of PM(2.5). In Alta Floresta, the percentage increases in the relative risk (%RR) of hospitalization for respiratory diseases in children were significant for the whole year and for the dry season with 3-4 day lags. In the dry season these measurements reach 6% (95%CI: 1.4-10.8). The associations were significant for moving averages of 3-5 days. The %RR for the elderly was significant for the current day of the drought, with a 6.8% increase (95%CI: 0.5-13.5) for each additional 10 mu g/m(3) of PM(2.5). No associations were verified for Tangara da Serra. The PM(2.5) from the burning of biomass increased hospitalizations for respiratory diseases in children and the elderly. | |||||
BibTeX:
@article{ignotti_air_2010, author = {Ignotti, Eliane and Hacon, Sandra de Souza and Junger, Washington Leite and Mourao, Dennys and Longo, Karla and Freitas, Saulo and Artaxo, Paulo and Monteiro Ponce de Leon, Antonio Carlos}, title = {Air pollution and hospital admissions for respiratory diseases in the subequatorial Amazon: a time series approach}, journal = {Cadernos De Saude Publica}, year = {2010}, volume = {26}, number = {4}, pages = {747--761}, note = {Edition: 2010/06/01}, url = {://WOS:000278148700011 http://www.scielo.br/pdf/csp/v26n4/17.pdf}, doi = {https://doi.org/10.1590/s0102-311x2010000400017} } |
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Ickes, K. and Williamson, G.B. | Edge effects and ecological processes: are they on the same scale? [BibTeX] |
2000 | Trends in Ecology & Evolution Vol. 15(9), pp. 373-373 |
article | DOI URL |
BibTeX:
@article{ickes_edge_2000, author = {Ickes, K. and Williamson, G. B.}, title = {Edge effects and ecological processes: are they on the same scale?}, journal = {Trends in Ecology & Evolution}, year = {2000}, volume = {15}, number = {9}, pages = {373--373}, url = {://WOS:000088863000014}, doi = {https://doi.org/10.1016/s0169-5347(00)01911-x} } |
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Ichii, K., Hashimoto, H., White, M.A., Potters, C., Hutyra, L.R., Huete, A.R., Myneni, R.B. and Nemanis, R.R. | Constraining rooting depths in tropical rainforests using satellite data and ecosystem modeling for accurate simulation of gross primary production seasonality | 2007 | Global Change Biology Vol. 13(1), pp. 67-77 |
article | DOI URL |
Abstract: Accurate parameterization of rooting depth is difficult but important for capturing the spatio-temporal dynamics of carbon, water and energy cycles in tropical forests. In this study, we adopted a new approach to constrain rooting depth in terrestrial ecosystem models over the Amazon using satellite data [moderate resolution imaging spectroradiometer (MODIS) enhanced vegetation index (EVI)] and Biome-BGC terrestrial ecosystem model. We simulated seasonal variations in gross primary production (GPP) using different rooting depths (1, 3, 5, and 10 m) at point and spatial scales to investigate how rooting depth affects modeled seasonal GPP variations and to determine which rooting depth simulates GPP consistent with satellite-based observations. First, we confirmed that rooting depth strongly controls modeled GPP seasonal variations and that only deep rooting systems can successfully track flux-based GPP seasonality at the Tapajos km67 flux site. Second, spatial analysis showed that the model can reproduce the seasonal variations in satellite-based EVI seasonality, however, with required rooting depths strongly dependent on precipitation and the dry season length. For example, a shallow rooting depth (1-3 m) is sufficient in regions with a short dry season (e.g. 0-2 months), and deeper roots are required in regions with a longer dry season (e.g. 3-5 and 5-10 m for the regions with 3-4 and 5-6 months dry season, respectively). Our analysis suggests that setting of proper rooting depths is important to simulating GPP seasonality in tropical forests, and the use of satellite data can help to constrain the spatial variability of rooting depth. | |||||
BibTeX:
@article{ichii_constraining_2007, author = {Ichii, Kazuhito and Hashimoto, Hirofumi and White, Michael A. and Potters, Christopher and Hutyra, Lucy R. and Huete, Alfredo R. and Myneni, Ranga B. and Nemanis, Ramakrishna R.}, title = {Constraining rooting depths in tropical rainforests using satellite data and ecosystem modeling for accurate simulation of gross primary production seasonality}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {1}, pages = {67--77}, url = {://WOS:000243403900006}, doi = {https://doi.org/10.1111/j.1365-2486.2006.01277.x} } |
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Rappaport. D, I, Morton, D.C., Longo, M., Keller, M., Dubayah, R. and Santos, M.N.d. | Quantifying long-term changes in carbon stocks and forest structure from Amazon forest degradation [BibTeX] |
2018 | Environmental Research Letters Vol. 13, pp. 065013 |
article | DOI |
BibTeX:
@article{i_quantifying_2018, author = {I, Rappaport. D and Morton, D C and Longo, M and Keller, M. and Dubayah, R and Santos, M. N dos-}, title = {Quantifying long-term changes in carbon stocks and forest structure from Amazon forest degradation}, journal = {Environmental Research Letters}, year = {2018}, volume = {13}, pages = {065013}, note = {Edition: http://iopscience.iop.org/article/10.1088/1748-9326/aac331}, doi = {https://doi.org/10.1088/1748-9326/aac331} } |
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Hutyra, L.R., Munger, J.W., Saleska, S.R., Gottlieb, E., Daube, B.C., Dunn, A.L., Amaral, D.F., de Camargo, P.B. and Wofsy, S.C. | Seasonal controls on the exchange of carbon and water in an Amazonian rain forest | 2007 | Journal of Geophysical Research-Biogeosciences Vol. 112(G3) |
article | DOI URL |
Abstract: [1] The long-term resilience of Amazonian forests to climate changes and the fate of their large stores of organic carbon depend on the ecosystem response to climate and weather. This study presents 4 years of eddy covariance data for CO2 and water fluxes in an evergreen, old-growth tropical rain forest examining the forest's response to seasonal variations and to short-term weather anomalies. Photosynthetic efficiency declined late in the wet season, before appreciable leaf litter fall, and increased after new leaf production midway through the dry season. Rates of evapotranspiration were inelastic and did not depend on dry season precipitation. However, ecosystem respiration was inhibited by moisture limitations on heterotrophic respiration during the dry season. The annual carbon balance for this ecosystem was very close to neutral, with mean net loss of 890 +/- 220 kg C ha(-1) yr(-1), and a range of -221 +/- 453 (C uptake) to +2677 +/- 488 (C loss) kg C ha(-1) yr(-1) over 4 years. The trend from large net carbon release in 2002 towards net carbon uptake in 2005 implies recovery from prior disturbance. The annual carbon balance was sensitive to weather anomalies, particularly the timing of the dry-to-wet season transition, reflecting modulation of light inputs and respiration processes. Canopy carbon uptake rates were largely controlled by phenology and light with virtually no indication of seasonal water limitation during the 5-month dry season, indicating ample supplies of plant-available-water and ecosystem adaptation for maximum light utilization. | |||||
BibTeX:
@article{hutyra_seasonal_2007, author = {Hutyra, Lucy R. and Munger, J. William and Saleska, Scott R. and Gottlieb, Elaine and Daube, Bruce C. and Dunn, Allison L. and Amaral, Daniel F. and de Camargo, Plinio B. and Wofsy, Steven C.}, title = {Seasonal controls on the exchange of carbon and water in an Amazonian rain forest}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2007}, volume = {112}, number = {G3}, url = {://WOS:000248600800001}, doi = {https://doi.org/10.1029/2006jg000365} } |
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Hutyra, L.R., Munger, J.W., Nobre, C.A., Saleska, S.R., Vieira, S.A. and Wofsy, S.C. | Climatic variability and vegetation vulnerability in Amazonia | 2005 | Geophysical Research Letters Vol. 32(24) |
article | DOI URL |
Abstract: Models of climate change predict close coupling between increases in aridity and conversion of Amazonian forests to savanna. Here we assess the vulnerability and resilience of Amazonian vegetation to climate change by analyzing observed climate-vegetation relationships using climate data, observed vegetation distributions, and evapotranspiration rates inferred from eddy flux data. We found that drought frequency is an excellent predictor of the forest-savanna boundary, indicating the key role of extreme climatic events for inducing vegetation change, and highlighting particularly vulnerable regions of Amazonia. | |||||
BibTeX:
@article{hutyra_climatic_2005, author = {Hutyra, L. R. and Munger, J. W. and Nobre, C. A. and Saleska, S. R. and Vieira, S. A. and Wofsy, S. C.}, title = {Climatic variability and vegetation vulnerability in Amazonia}, journal = {Geophysical Research Letters}, year = {2005}, volume = {32}, number = {24}, url = {://WOS:000234364400007 http://www.agu.org/pubs/crossref/2005/2005GL024981.shtml}, doi = {https://doi.org/10.1029/2005gl024981} } |
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Hutyra, L.R., Munger, J.W., Hammond-Pyle, E., Saleska, S.R., Restrepo-Coupe, N., Daube, B.C., de Camargo, P.B. and Wofsy, S.C. | Resolving systematic errors in estimates of net ecosystem exchange of CO2 and ecosystem respiration in a tropical forest biome | 2008 | Agricultural and Forest Meteorology Vol. 148(8-9), pp. 1266-1279 |
article | DOI URL |
Abstract: The controls on uptake and release Of CO2 by tropical rainforests, and the responses to a changing climate, are major uncertainties in global climate change models. Eddy-covariance measurements potentially provide detailed data on CO2 exchange and responses to the environment in these forests, but accurate estimates of the net ecosystem exchange of CO2 (NEE) and ecosystem respiration (R-eco) require careful analysis of data representativity, treatment of data gaps, and correction for systematic errors. This study uses the comprehensive data from our study site in an old-growth tropical rainforest near Santarem, Brazil, to examine the biases in NEE and R-eco potentially associated with the two most important sources of systematic error in Eddy-covariance data: lost nighttime flux and missing canopy storage measurements. We present multiple estimates for the net carbon balance and Reco at our site, including the conventional "u* filter", a detailed bottom-up budget for respiration, estimates by similarity with Rn-122, and an independent estimate of respiration by extrapolation of daytime Eddy flux data to zero light. Eddy-covariance measurements between 2002 and 2006 showed a mean net ecosystem carbon loss of 0.25 +/- 0.04 mu mol m(-2) s(-1), with a mean respiration rate of 8.60 +/- 10.11 mu mol m(-2) s(-1) at our site. We found that lost nocturnal flux can potentially introduce significant bias into these results. We develop robust approaches to correct for these biases, showing that, where appropriate, a site-specific u* threshold can be used to avoid systematic bias in estimates of carbon exchange. Because of the presence of gaps in the data and the day-night asymmetry between storage and turbulence, inclusion of canopy storage is essential to accurate assessments of NEE. We found that short-terrn measurements of storage may be adequate to accurately model storage for use in obtaining ecosystem carbon balance, at sites where storage is not routinely measured. The analytical framework utilized in this study can be applied to other Eddy-covariance sites to help correct and validate measurements of the carbon cycle and its components. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{hutyra_resolving_2008, author = {Hutyra, Lucy R. and Munger, J. William and Hammond-Pyle, Elizabeth and Saleska, Scott R. and Restrepo-Coupe, Natalia and Daube, Bruce C. and de Camargo, Plinio B. and Wofsy, Steven C.}, title = {Resolving systematic errors in estimates of net ecosystem exchange of CO2 and ecosystem respiration in a tropical forest biome}, journal = {Agricultural and Forest Meteorology}, year = {2008}, volume = {148}, number = {8-9}, pages = {1266--1279}, url = {://WOS:000258128000006}, doi = {https://doi.org/10.1016/j.agrformet.2008.03.007} } |
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Hurtt, G., Xiao, X.M., Keller, M., Palace, M., Asner, G.P., Braswell, R., Brondizio, E.S., Cardoso, M., Carvalho, C.J.R., Fearon, M.G., Guild, L., Hagen, S., Hetrick, S., Moore, B., Nobre, C., Read, J.M., Sa, T., Schloss, A., Vourlitis, G. and Wickel, A.J. | IKONOS imagery for the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) | 2003 | Remote Sensing of Environment Vol. 88(1-2), pp. 111-127 |
article | DOI URL |
Abstract: The LBA-ECO program is one of several international research components under the Brazilian-led Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). The field-oriented research activities of this study are organized along transects and include a set of primary field sites, where the major objective is to study land-use change and ecosystem dynamics, and a smaller set of 15 operational eddy flux tower sites, where the major objective is to quantify net exchange Of CO2 with the atmosphere. To supplement these studies and help to address issues of fine-scale spatial heterogeneity and scaling, high-resolution satellite imagery (IKONOS, 1-4 m) have been acquired over some of these study sites. This paper begins with a description of the acquisition strategy and IKONOS holdings for LBA. This section is followed with a review of some of the most promising new applications of these data in LBA. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{hurtt_ikonos_2003, author = {Hurtt, G. and Xiao, X. M. and Keller, M. and Palace, M. and Asner, G. P. and Braswell, R. and Brondizio, E. S. and Cardoso, M. and Carvalho, C. J. R. and Fearon, M. G. and Guild, L. and Hagen, S. and Hetrick, S. and Moore, B. and Nobre, C. and Read, J. M. and Sa, T. and Schloss, A. and Vourlitis, G. and Wickel, A. J.}, title = {IKONOS imagery for the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {88}, number = {1-2}, pages = {111--127}, url = {://WOS:000187078500010}, doi = {https://doi.org/10.1016/j.rse.2003.04.004} } |
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Huntingford, C., Zelazowski, P., Galbraith, D., Mercado, L.M., Sitch, S., Fisher, R., Lomas, M., Walker, A.P., Jones, C., Booth, B.B., Malhi, Y., Hemming, D., Kay, G., Good, P., Lewis, S., Phillips, O., Atkin, O., Lloyd, J., Gloor, E., Zaragoza-Castells, J., Meir, P., Betts, R.A., Harris, P., Nobre, C., Marengo, J. and Cox, P. | Simulated resilience of tropical rainforests to CO2-induced climate change [BibTeX] |
2013 | Nature Geoscience Vol. 6(4), pp. 268-273 |
article | |
BibTeX:
@article{huntingford_simulated_2013, author = {Huntingford, C. and Zelazowski, P. and Galbraith, D. and Mercado, L. M. and Sitch, S. and Fisher, R. and Lomas, M. and Walker, A. P. and Jones, C.D. and Booth, B.B. B. and Malhi, Y. and Hemming, D. and Kay, G. and Good, P. and Lewis, S.L. and Phillips, O.L. and Atkin, O.K. and Lloyd, J. and Gloor, E. and Zaragoza-Castells, J. and Meir, P. and Betts, R. A. and Harris, P.P. and Nobre, C. and Marengo, J. and Cox, P.M.}, title = {Simulated resilience of tropical rainforests to CO2-induced climate change}, journal = {Nature Geoscience}, year = {2013}, volume = {6}, number = {4}, pages = {268--273} } |
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Huntingford, C., Harris, P.P., Gedney, N., Cox, P.M., Betts, R.A., Marengo, J.A. and Gash, J.H.C. | Using a GCM analogue model to investigate the potential for Amazonian forest dieback | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 177-185 |
article | DOI URL |
Abstract: A combined GCM analogue model and GCM land surface representation is used to investigate the influences of climatology and land surface parameterisation on modelled Amazonian vegetation change. This modelling structure (called IMOGEN) captures the main features of the changes in surface climate as estimated by a GCM with enhanced atmospheric greenhouse gas concentrations. Advantage is taken of IMOGEN's computational speed which allows multiple simulations to be carried out to assess the robustness of the GCM results. The timing of forest dieback is found to be sensitive to the initial "pre-industrial" climate, as well as uncertainties in the representation of land-atmosphere CO2 exchange. Changing from a Q(10) form for plant dark and maintanence respiration (as used in the coupled GCM runs) to a respiration proportional to maximum photosynthesis, reduces the biomass lost from Amazonia in the 21st century. Replacing the GCM control climate (which has about 25% too little rain in the annual mean over Amazonia) with an observed climatology increases the CO2 concentration at which rainfall drops to critical levels, and thereby further delays the dieback. On the other hand, calibration of the canopy photosynthesis model against Amazonian flux data tends to lead to earlier forest dieback. Further advances are required in both GCM rainfall simulation and land-surface process representation before a clearer picture will emerge on the timing of possible Amazonian forest dieback. However, it seems likely that these advances will overall lead to projections of later forest dieback as GCM control climates become more realistic. | |||||
BibTeX:
@article{huntingford_using_2004, author = {Huntingford, C. and Harris, P. P. and Gedney, N. and Cox, P. M. and Betts, R. A. and Marengo, J. A. and Gash, J. H. C.}, title = {Using a GCM analogue model to investigate the potential for Amazonian forest dieback}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {177--185}, url = {://WOS:000222024700013}, doi = {https://doi.org/10.1007/s00704-004-0051-x} } |
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Huntingford, C., Fisher, R.A., Mercado, L., Booth, B.B.B., Sitch, S., Harris, P.P., Cox, P.M., Jones, C.D., Betts, R.A., Malhi, Y., Harris, G.R., Collins, M. and Moorcroft, P. | Towards quantifying uncertainty in predictions of Amazon 'dieback' | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1857-1864 |
article | DOI URL |
Abstract: Simulations with the Hadley Centre general circulation model (HadCM3), including carbon cycle model and forced by a 'business-as-usual' emissions scenario, predict a rapid loss of Amazonian rainforest from the middle of this century onwards. The robustness of this projection to both uncertainty in physical climate drivers and the formulation of the land surface scheme is investigated. We analyse how the modelled vegetation cover in Amazonia responds to (i) uncertainty in the parameters specified in the atmosphere component of HadCM3 and their associated influence on predicted surface climate. We then enhance the land surface description and (ii) implement a multilayer canopy light interception model and compare with the simple 'big-leaf' approach used in the original simulations. Finally, (iii) we investigate the effect of changing the method of simulating vegetation dynamics from an area-based model (TRIFFID) to a more complex size-and age-structured approximation of an individual-based model (ecosystem demography). We find that the loss of Amazonian rainforest is robust across the climate uncertainty explored by perturbed physics simulations covering a wide range of global climate sensitivity. The introduction of the refined light interception model leads to an increase in simulated gross plant carbon uptake for the present day, but, with altered respiration, the net effect is a decrease in net primary productivity. However, this does not significantly affect the carbon loss from vegetation and soil as a consequence of future simulated depletion in soil moisture; the Amazon forest is still lost. The introduction of the more sophisticated dynamic vegetation model reduces but does not halt the rate of forest dieback. The potential for human-induced climate change to trigger the loss of Amazon rainforest appears robust within the context of the uncertainties explored in this paper. Some further uncertainties should be explored, particularly with respect to the representation of rooting depth. | |||||
BibTeX:
@article{huntingford_towards_2008, author = {Huntingford, Chris and Fisher, Rosie A. and Mercado, Lina and Booth, Ben B. B. and Sitch, Stephen and Harris, Phil P. and Cox, Peter M. and Jones, Chris D. and Betts, Richard A. and Malhi, Yadvinder and Harris, Glen R. and Collins, Mat and Moorcroft, Paul}, title = {Towards quantifying uncertainty in predictions of Amazon 'dieback'}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1857--1864}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500018}, doi = {https://doi.org/10.1098/rstb.2007.0028} } |
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Hunter, M.O., Keller, M., Morton, D., Cook, B., Lefsky, M., Ducey, M., Saleska, S., Oliveira Junior, R.C.d. and Schietti, J. | Structural dynamics of tropical moist forest gaps [BibTeX] |
2015 | PLos ONE Vol. 10(7) |
article | |
BibTeX:
@article{hunter_structural_2015, author = {Hunter, M. O. and Keller, M. and Morton, D. and Cook, B. and Lefsky, M. and Ducey, M. and Saleska, S. and Oliveira Junior, R. C. de and Schietti, J.}, title = {Structural dynamics of tropical moist forest gaps}, journal = {PLos ONE}, year = {2015}, volume = {10}, number = {7} } |
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Huffman, J., Sinha, B., Garland, R., Snee-Pollmann, A., Gunthe, S., Artaxo, P., Martin, S., Andreae, M. and Poschl, U. | Size distributions and temporal variations of biological aerosol particles in the Amazon rainforest characterized by microscopy and real-time UV-APS fluorescence techniques during AMAZE-08 [BibTeX] |
2012 | Atmos. Chem. Phys. Vol. 12, pp. 11997-12019 |
article | |
BibTeX:
@article{huffman_size_2012, author = {Huffman, J.A. and Sinha, B. and Garland, R.M. and Snee-Pollmann, A. and Gunthe, S.S. and Artaxo, P. and Martin, S.T. and Andreae, M.O. and Poschl, U.}, title = {Size distributions and temporal variations of biological aerosol particles in the Amazon rainforest characterized by microscopy and real-time UV-APS fluorescence techniques during AMAZE-08}, journal = {Atmos. Chem. Phys.}, year = {2012}, volume = {12}, pages = {11997--12019} } |
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Huffman, J., Sinha, B., Garland, R., Snee-Pollmann, A., Gunthe, S., Artaxo, P., Martin, S., Andreae, M. and Poschl, U. | Biological aerosol particle concentrations and size distributions measured in pristine tropical rainforest air during AMAZE-08 [BibTeX] |
2012 | Atmos. Chem. Phys. Discuss. Vol. 12, pp. 25181-25236 |
article | |
BibTeX:
@article{huffman_biological_2012, author = {Huffman, J.A. and Sinha, B. and Garland, R.M. and Snee-Pollmann, A. and Gunthe, S.S. and Artaxo, P. and Martin, S.T. and Andreae, M.O. and Poschl, U.}, title = {Biological aerosol particle concentrations and size distributions measured in pristine tropical rainforest air during AMAZE-08}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2012}, volume = {12}, pages = {25181--25236} } |
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Huete, A.R., Restrepo-Coupe, N., Ratana, P., Didan, K., Saleska, S.R., Ichii, K., Panuthai, S. and Gamo, M. | Multiple site tower flux and remote sensing comparisons of tropical forest dynamics in Monsoon Asia | 2008 | Agricultural and Forest Meteorology Vol. 148(5), pp. 748-760 |
article | DOI URL |
Abstract: The spatial and temporal dynamics of tropical forest functioning are poorly understood, partly attributed to a weak seasonality and high tree species diversity at the landscape scale. Recent neotropical rainforest studies with local tower flux measurements have revealed strong seasonal carbon fluxes that follow the availability of sunlight in intact forests, while in areas of forest disturbance, carbon fluxes more closely tracked seasonal water availability. These studies also showed a strong seasonal correspondence of satellite measures of greenness, using the Enhanced Vegetation index (E(VI)) with ecosystem carbon fluxes in both intact and disturbed forests, which may enable larger scale extension of tower flux measurements. In this study, we investigated the seasonal patterns and relationships of local site tower flux measures of gross primary productivity (P(g)) with independent Moderate Resolution Imaging Spectroradiometer (MODIS) satellite greenness measures across three Monsoon Asia tropical forest types, encompassing drought-deciduous, dry evergreen, and humid evergreen secondary tropical forests. In contrast to neotropical forests, the tropical forests of Monsoon Asia are more extensively degraded and heterogeneous due to intense land use pressures, and therefore, may exhibit unique seasonal patterns of ecosystem fluxes that are more likely water-limited and drought-susceptible. Our results show significant phenologic variability and response to moisture and light controls across the three tropical forest sites and at the regional scale. The drier tropical forests were primarily water-limited, while the wet evergreen secondary forest showed a slight positive trend with light availability. Satellite E(VI) greenness observations were generally synchronized and linearly related with seasonal and inter-annual tower flux P(g) measurements at the multiple sites and provided better opportunities for tower extension of carbon fluxes than other satellite products, such as the MODIS P(g) product. Satellite E(VI)-derived P(g) images revealed strong seasonal variations in photosynthetic activity throughout the Monsoon Asia tropical region. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{huete_multiple_2008, author = {Huete, A. R. and Restrepo-Coupe, N. and Ratana, P. and Didan, K. and Saleska, S. R. and Ichii, K. and Panuthai, S. and Gamo, M.}, title = {Multiple site tower flux and remote sensing comparisons of tropical forest dynamics in Monsoon Asia}, journal = {Agricultural and Forest Meteorology}, year = {2008}, volume = {148}, number = {5}, pages = {748--760}, url = {://WOS:000256691700006}, doi = {https://doi.org/10.1016/j.agrformet.2008.01.012} } |
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Huete, A.R., Didan, K., Shimabukuro, Y.E., Ratana, P., Saleska, S.R., Hutyra, L.R., Yang, W.Z., Nemani, R.R. and Myneni, R. | Amazon rainforests green-up with sunlight in dry season | 2006 | Geophysical Research Letters Vol. 33(6) |
article | DOI URL |
Abstract: Metabolism and phenology of Amazon rainforests significantly influence global dynamics of climate, carbon and water, but remain poorly understood. We analyzed Amazon vegetation phenology at multiple scales with Moderate Resolution Imaging Spectroradiometer ( MODIS) satellite measurements from 2000 to 2005. MODIS Enhanced Vegetation Index (EVI, an index of canopy photosynthetic capacity) increased by 25% with sunlight during the dry season across Amazon forests, opposite to ecosystem model predictions that water limitation should cause dry season declines in forest canopy photosynthesis. In contrast to intact forests, areas converted to pasture showed dry-season declines in EVI-derived photosynthetic capacity, presumably because removal of deep-rooted forest trees reduced access to deep soil water. Local canopy photosynthesis measured from eddy flux towers in both a rainforest and forest conversion site confirm our interpretation of satellite data, and suggest that basin-wide carbon fluxes can be constrained by integrating remote sensing and local flux measurements. | |||||
BibTeX:
@article{huete_amazon_2006, author = {Huete, A. R. and Didan, K. and Shimabukuro, Y. E. and Ratana, P. and Saleska, S. R. and Hutyra, L. R. and Yang, W. Z. and Nemani, R. R. and Myneni, R.}, title = {Amazon rainforests green-up with sunlight in dry season}, journal = {Geophysical Research Letters}, year = {2006}, volume = {33}, number = {6}, url = {://WOS:000236344800009 http://www.agu.org/pubs/crossref/2006/2005GL025583.shtml}, doi = {https://doi.org/10.1029/2005gl025583} } |
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Huete, A., Didan, K., Miura, T., Rodriguez, E.P., Gao, X. and Ferreira, L.G. | Overview of the radiometric and biophysical performance of the MODIS vegetation indices | 2002 | Remote Sensing of Environment Vol. 83(1-2), pp. 195-213 |
article | DOI URL |
Abstract: We evaluated the initial 12 months of vegetation index product availability from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Earth Observing System-Terra platform. Two MODIS vegetation indices (VI), the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI), are produced at 1-km and 500-m resolutions and 16-day compositing periods. This paper presents an initial analysis of the MODIS NDVI and EVI performance from both radiometric and biophysical perspectives. We utilize a combination of site-intensive and regionally extensive approaches to demonstrate the performance and validity of the two indices. Our results showed a good correspondence between airborne-measured, top-of-canopy reflectances and VI values with those from the MODIS sensor at four intensively measured test sites representing semi-arid grass/shrub, savanna, and tropical forest biomes. Simultaneously derived field biophysical measures also demonstrated the scientific utility of the MODIS VI. Multitemporal profiles of the MODIS VIs over numerous biome types in North and South America well represented their seasonal phenologies. Comparisons of the MODIS-NDVI with the NOAA-14, 1-km AVHRR-NDVI temporal profiles showed that the MODIS-based index performed with higher fidelity. The dynamic range of the MODIS VIs are presented and their sensitivities in discriminating vegetation differences are evaluated in sparse and dense vegetation areas. We found the NDVI to asymptotically saturate in high biomass regions such as in the Amazon while the EVI remained sensitive to canopy variations. (C) 2002 Elsevier Science Inc. All rights reserved. | |||||
BibTeX:
@article{huete_overview_2002, author = {Huete, A. and Didan, K. and Miura, T. and Rodriguez, E. P. and Gao, X. and Ferreira, L. G.}, title = {Overview of the radiometric and biophysical performance of the MODIS vegetation indices}, journal = {Remote Sensing of Environment}, year = {2002}, volume = {83}, number = {1-2}, pages = {195--213}, url = {://WOS:000179160200014}, doi = {https://doi.org/10.1016/s0034-4257(02)00096-2} } |
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Huang, M., Asner, G.P., Keller, M. and Berry, J.A. | An ecosystem model for tropical forest disturbance and selective logging | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113(G1) |
article | DOI URL |
Abstract: [1] A new three-dimensional version of the Carnegie-Ames-Stanford Approach (CASA) ecosystem model (CASA-3D) was developed to simulate regional carbon cycling in tropical forest ecosystems after disturbances such as logging. CASA-3D has the following new features: (1) an alternative approach for calculating absorbed photosynthetically active radiation (APAR) using new high-resolution satellite images of forest canopy gap fraction; (2) a pulse disturbance module to modify aboveground carbon pools following forest disturbance; (3) a regrowth module that simulates changes in community composition by considering gap phase regeneration; and (4) a radiative transfer module to simulate the dynamic three-dimensional light environment above the canopy and within gaps after forest disturbance. The model was calibrated with and tested against field observations from experimental logging plots in the Large-scale Biosphere Atmosphere Experiment in Amazonia (LBA) project. The sensitivity of key model parameters was evaluated using Monte Carlo simulations, and the uncertainties in simulated NPP and respiration associated with model parameters and meteorological variables were assessed. We found that selective logging causes changes in forest architecture and composition that result in a cascading set of impacts on the carbon cycling of rainforest ecosystems. Our model sensitivity and uncertainty analyses also highlight the paramount importance of measuring changes in canopy gap fraction from satellite data, as well as canopy light-use efficiency from ecophysiological measurements, to understand the role of forest disturbance on landscape and regional carbon cycling in tropical forests. In sum, our study suggests that CASA-3D may be suitable for regional-scale applications to assess the large-scale effects of selective logging, to provide guidance for forest management, and to understand the role of forest disturbance in regional and global climate studies. | |||||
BibTeX:
@article{huang_ecosystem_2008, author = {Huang, Maoyi and Asner, Gregory P. and Keller, Michael and Berry, Joseph A.}, title = {An ecosystem model for tropical forest disturbance and selective logging}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, number = {G1}, url = {://WOS:000252362800001}, doi = {https://doi.org/10.1029/2007jg000438} } |
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Huang, X., Longo, Y., Keller, M., Knox, M., Koven, R., & Fisher, C. and M., R. | Assessing impacts of selective logging on water, energy, and carbon budgets and ecosystem dynamics in Amazon forests using the Functionally Assembled Terrestrial Ecosystem Simulator [BibTeX] |
2019 | Biogeosciences Discussions, pp. 1-46 | article | DOI |
BibTeX:
@article{huang_assessing_2019, author = {Huang, Xu, Y., Longo, M., Keller, M., Knox, R., Koven, C., & Fisher, R., M.}, title = {Assessing impacts of selective logging on water, energy, and carbon budgets and ecosystem dynamics in Amazon forests using the Functionally Assembled Terrestrial Ecosystem Simulator}, journal = {Biogeosciences Discussions}, year = {2019}, pages = {1--46}, doi = {https://doi.org/10.5194/bg-2019-129} } |
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Hu, Z., Xu, C., McDowell, N., Johnson, D., Wang, M., Huang, Z. and Zhou, X. | Linking microbial community composition to C loss during wood decomposition [BibTeX] |
2017 | Soil Biology and Biochemistry Vol. 104, pp. 108-116 |
article | |
BibTeX:
@article{hu_linking_2017, author = {Hu, Z. and Xu, C. and McDowell, N.G. and Johnson, D.J. and Wang, M. and Huang, Z. and Zhou, X.}, title = {Linking microbial community composition to C loss during wood decomposition}, journal = {Soil Biology and Biochemistry}, year = {2017}, volume = {104}, pages = {108--116} } |
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Hu, W.W., Campuzano-Jost, P., Palm, B.B., Day, D.A., Ortega, A.M., Hayes, P., Krechmer, J.E., Chen, Q., Kuwata, M., Liu, Y.J., de Sá, S.S., K. McKinney, S. T. Martin, M. Hu, Budisulistiorini, S.H., Riva, M., J. D. Surratt, J. M. St. Clair, Isaacman-Van Wertz, G., Yee, L.D., Goldstein, A.H., Carbone, S., Brito, J., Artaxo, P., Gouw, J.A.d., Koss, A., Wisthaler, A., Mikoviny, T., Karl, T., Kaser, L., Jud, W., Hansel, A., Docherty, K.S., Alexander, M.L., Robinson, N.H., Coe, H., Allan, J.D., Canagaratna, M.R., Paulot, F. and Jimenez, J.L. | Characterization of a real-time tracer for isoprene epoxydiols-derived secondary organic aerosol (IEPOX-SOA) from aerosol mass spectrometer measurements [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 11807-11833 |
article | DOI |
BibTeX:
@article{hu_characterization_2015, author = {Hu, W. W. and Campuzano-Jost, P. and Palm, B. B. and Day, D. A. and Ortega, A. M. and Hayes, P.L. and Krechmer, J. E. and Chen, Q. and Kuwata, M. and Liu, Y. J. and de Sá, S. S. and K. McKinney and S. T. Martin and M. Hu and Budisulistiorini, S. H. and Riva, M. and J. D. Surratt and J. M. St. Clair and Isaacman-Van Wertz, G. and Yee, L. D. and Goldstein, A. H. and Carbone, S. and Brito, J. and Artaxo, P. and Gouw, J. A. de and Koss, A. and Wisthaler, A. and Mikoviny, T. and Karl, T. and Kaser, L. and Jud, W. and Hansel, A. and Docherty, K. S. and Alexander, M. L. and Robinson, N. H. and Coe, H. and Allan, J. D. and Canagaratna, M. R. and Paulot, F. and Jimenez, J. L.}, title = {Characterization of a real-time tracer for isoprene epoxydiols-derived secondary organic aerosol (IEPOX-SOA) from aerosol mass spectrometer measurements}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {11807--11833}, doi = {https://doi.org/10.5194/acp-15-11807-2015} } |
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Hu, W., Palm, B.B., Day, D.A., Campuzano-Jost, P., Krechmer, J.E., Peng, Z., Sá, S.S.d., Martin, S.T. and M. Lizabeth Alexander Lina Hacker, A.K.-S.A.R.K.J.A.d.G.A.H.G.R.S.S.J.S.J.-H.P.A.B.G.S.K.F.C.A.S.H.P.W.H.B.and.J.L.J.K.B. | Volatility and lifetime against OH heterogeneous reaction of ambient isoprene-epoxydiols-derived secondary organic aerosol (IEPOX-SOA) [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 11563-11580 |
article | DOI |
BibTeX:
@article{hu_volatility_2016, author = {Hu, Weiwei and Palm, Brett B. and Day, Douglas A. and Campuzano-Jost, Pedro and Krechmer, Jordan E. and Peng, Zhe and Sá, Suzane S. de and Martin, Scot T. and M. Lizabeth Alexander, Lina Hacker, Astrid Kiendler-Scharr, Abigail R. Koss, Joost A. de Gouw, Allen H. Goldstein, Roger Seco, Steven J. Sjostedt, Jeong-Hoo Park, Alex B. Guenther, Saewung Kim, Francesco Canonaco, André S. H. Prévôt, William H. Brune, and Jose L. Jimenez, Karsten Baumann}, title = {Volatility and lifetime against OH heterogeneous reaction of ambient isoprene-epoxydiols-derived secondary organic aerosol (IEPOX-SOA)}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {11563--11580}, doi = {https://doi.org/10.5194/acp-16-11563-2016} } |
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Houghton, R.A., Skole, D.L., Nobre, C.A., Hackler, J.L., Lawrence, K.T. and Chomentowski, W.H. | Annual fluxes or carbon from deforestation and regrowth in the Brazilian Amazon | 2000 | Nature Vol. 403(6767), pp. 301-304 |
article | DOI URL |
Abstract: The distribution of sources and sinks of carbon among the world's ecosystems is uncertain. Some analyses show northern midlatitude lands to be a large sink, whereas the tropics are a net source(1); other analyses show the tropics to be nearly neutral. whereas northern mid-latitudes are a small sink(2,3). Here we show that the annual flux of carbon from deforestation and abandonment of agricultural lands in the Brazilian Amazon was a source of about 0.2 g C yr(-1) over the period 1989-1998 (1 Pg is 10(15) g). This estimate is based on annual rates of deforestation and spatially detailed estimates of deforestation, regrowing forests and biomass. Logging may add another 5-10% to this estimate(4), and fires may double the magnitude of the source in years following a drought(4), The annual source of carbon from land-use change and fire approximately offsets the sink calculated for natural ecosystems in the region(5,6). Thus this large area of tropical forest is nearly balanced with respect to carbon, but has an interannual variability of +/- 0.2 PgC yr(-1). | |||||
BibTeX:
@article{houghton_annual_2000, author = {Houghton, R. A. and Skole, D. L. and Nobre, C. A. and Hackler, J. L. and Lawrence, K. T. and Chomentowski, W. H.}, title = {Annual fluxes or carbon from deforestation and regrowth in the Brazilian Amazon}, journal = {Nature}, year = {2000}, volume = {403}, number = {6767}, pages = {301--304}, note = {Edition: 2000/02/05}, url = {://WOS:000084899700050 http://www.nature.com/nature/journal/v403/n6767/pdf/403301a0.pdf}, doi = {https://doi.org/10.1038/35002062} } |
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Houghton, R.A., Lawrence, K.T., Hackler, J.L. and Brown, S. | The spatial distribution of forest biomass in the Brazilian Amazon: a comparison of estimates | 2001 | Global Change Biology Vol. 7(7), pp. 731-746 |
article | DOI URL |
Abstract: The amount of carbon released to the atmosphere as a result of deforestation is determined, in part, by the amount of carbon held in the biomass of the forests converted to other uses. Uncertainty in forest biomass is responsible for much of the uncertainty in current estimates of the flux of carbon from land-use change. In the present contribution several estimates of forest biomass are compared for the Brazilian Amazon, based on spatial interpolations of direct measurements, relationships to climatic variables, and remote sensing data. Three questions were posed: First, do the methods yield similar estimates? Second, do they yield similar spatial patterns of distribution of biomass? And, third, what factors need most attention if we are to predict more accurately the distribution of forest biomass over large areas? The answer to the first two questions is that estimates of biomass for Brazil's Amazonian forests (including dead and belowground biomass) vary by more than a factor of two, from a low of 39 PgC to a high of 93 PgC. Furthermore, the estimates disagree as to the regions of high and low biomass. The lack of agreement among estimates confirms the need for reliable determination of aboveground biomass over large areas. Potential methods include direct measurement of biomass through forest inventories with improved allometric regression equations, dynamic modelling of forest recovery following observed stand-replacing disturbances, and estimation of aboveground biomass from airborne or satellite-based instruments sensitive to the vertical structure plant canopies. | |||||
BibTeX:
@article{houghton_spatial_2001, author = {Houghton, R. A. and Lawrence, K. T. and Hackler, J. L. and Brown, S.}, title = {The spatial distribution of forest biomass in the Brazilian Amazon: a comparison of estimates}, journal = {Global Change Biology}, year = {2001}, volume = {7}, number = {7}, pages = {731--746}, url = {://WOS:000172097300001}, doi = {https://doi.org/10.1046/j.1365-2486.2001.00426.x} } |
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Houghton, R.A., Gloor, M., Lloyd, J. and Potter, C. | The Regional Carbon Budget [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 409-428 |
incollection | |
BibTeX:
@incollection{m_keller_regional_2009, author = {Houghton, R. A. and Gloor, Manuel and Lloyd, Jon and Potter, Christopher}, title = {The Regional Carbon Budget}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {409--428} } |
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Hoosbeek, M., Schaap, K.J. and Quesada, C.A. | Depth Differentiation of Carbon, Nitrogen and Phosphorous Cycling in Litter and Soil in Central Amazonia: Availability of Organic P May Limit the Response to Increasing Atmospheric CO2 [BibTeX] |
2021 | SSRN | article | DOI |
BibTeX:
@article{hoosbeek_depth_2021, author = {Hoosbeek, M. and Schaap, K. J. and Quesada, C. A.}, title = {Depth Differentiation of Carbon, Nitrogen and Phosphorous Cycling in Litter and Soil in Central Amazonia: Availability of Organic P May Limit the Response to Increasing Atmospheric CO2}, journal = {SSRN}, year = {2021}, doi = {https://doi.org/10.2139/ssrn.3990652} } |
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Honorio Coronado, E.N., Baker, T.R., Phillips, O.L., Pitman, N.C.A., Pennington, R.T., Vasquez Martinez, R., Monteagudo, A., Mogollon, H., Davila Cardozo, N., Rios, M., Garcia-Villacorta, R., Valderrama, E., Ahuite, M., Huamantupa, I., Neill, D.A., Laurance, W.F., Nascimento, H.E.M., de Almeida, S.S., Killeen, T.J., Arroyo, L., Nunez, P. and Freitas Alvarado, L. | Multi-scale comparisons of tree composition in Amazonian terra firme forests | 2009 | Biogeosciences Vol. 6(11), pp. 2719-2731 |
article | URL |
Abstract: We explored the floristic composition of terra firme forests across Amazonia using 55 plots. Firstly, we examined the floristic patterns using both genus- and species-level data and found that the species-level analysis more clearly distinguishes among forests. Next, we compared the variation in plot floristic composition at regional- and continental-scales, and found that average among-pair floristic similarity and its decay with distance behave similarly at regional- and continental-scales. Nevertheless, geographical distance had different effects on floristic similarity within regions at distances textless100 km, where north-western and southwestern Amazonian regions showed greater floristic variation than plots of central and eastern Amazonia. Finally, we quantified the role of environmental factors and geographical distance for determining variation in floristic composition. A partial Mantel test indicated that while geographical distance appeared to be more important at continental scales, soil fertility was crucial at regional scales within western Amazonia, where areas with similar soil conditions were more likely to share a high number of species. Overall, these results suggest that regional-scale variation in floristic composition can rival continental-scale differences within Amazonian terra firme forests, and that variation in floristic composition at both scales is influenced by geographical distance and environmental factors, such as climate and soil fertility. To fully account for regional-scale variation in continental studies of floristic composition, future floristic studies should focus on forest types poorly represented at regional scales in current datasets, such as terra firme forests with high soil fertility in north-western Amazonia. | |||||
BibTeX:
@article{honorio_coronado_multi-scale_2009, author = {Honorio Coronado, E. N. and Baker, T. R. and Phillips, O. L. and Pitman, N. C. A. and Pennington, R. T. and Vasquez Martinez, R. and Monteagudo, A. and Mogollon, H. and Davila Cardozo, N. and Rios, M. and Garcia-Villacorta, R. and Valderrama, E. and Ahuite, M. and Huamantupa, I. and Neill, D. A. and Laurance, W. F. and Nascimento, H. E. M. and de Almeida, S. Soares and Killeen, T. J. and Arroyo, L. and Nunez, P. and Freitas Alvarado, L.}, title = {Multi-scale comparisons of tree composition in Amazonian terra firme forests}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {11}, pages = {2719--2731}, url = {://WOS:000272232200027} } |
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Holmes, T.P., Blate, G.M., Zweede, J.C., Pereira, R., Barreto, P., Boltz, F. and Bauch, R. | Financial and ecological indicators of reduced impact logging performance in the eastern Amazon | 2002 | Forest Ecology and Management Vol. 163(1-3), pp. 93-110 |
article | DOI URL |
Abstract: Reduced impact logging (RIL) systems are currently being promoted in Brazil and other tropical countries in response to domestic and international concern over the ecological and economic sustainability of harvesting natural tropical forests. RIL systems are necessary, but not sufficient, for sustainable forest management because they reduce damage to the forest ecosystem during the initial forest entry. If conditions were identified where RIL costs were clearly less than conventional logging (CL) costs, then a strong incentive for RIL adoption would exist. In this paper, a comparison of costs and revenues was made for typical RIL and CL operations in the eastern Amazon. An economic engineering approach was used to estimate standardized productivity and cost parameters. Detailed data on productivity, harvest volume, wasted wood and damage to the residual stand were collected from operational scale harvest blocks. Productivity and cost data were also collected using surveys of forest products firms. The major conclusion of the study was that RIL was less costly, and more profitable, than CL under the conditions observed at the eastern Amazon study site. Full cost accounting methods were introduced to capture the direct and indirect costs associated with wasted wood. The impact of wasted wood on effective stumpage price provided the largest gain to RIL. Large gains attributable to RIL technology were also observed in skidding and log deck productivity. In addition, investment in RIL yielded an "environmental dividend" in terms of reduced damage to trees in the residual stand and reduction of the amount of ground area disturbed by heavy machinery. Developing institutions that can monetize the value of the environmental dividend remains a major challenge in the promotion of sustainable forest management in the tropics. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{holmes_financial_2002, author = {Holmes, T. P. and Blate, G. M. and Zweede, J. C. and Pereira, R. and Barreto, P. and Boltz, F. and Bauch, R.}, title = {Financial and ecological indicators of reduced impact logging performance in the eastern Amazon}, journal = {Forest Ecology and Management}, year = {2002}, volume = {163}, number = {1-3}, pages = {93--110}, url = {://WOS:000176460500008}, doi = {https://doi.org/10.1016/s0378-1127(01)00530-8} } |
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Holmes, K.W., Roberts, D.A., Sweeney, S., Numata, I., Matricardi, E., Biggs, T.W., Batista, G. and Chadwick, O.A. | Soil databases and the problem of establishing regional biogeochemical trends | 2004 | Global Change Biology Vol. 10(5), pp. 796-814 |
article | DOI URL |
Abstract: Regional and global environmental modeling depend on soil data for input layers or parameterization. However, randomly located observations, such as provided by agricultural databases, are not always representative of trends identified in field studies conducted under carefully controlled conditions. Many researchers lament the paucity of soil profile data in Amazonia, and suggest that given more data, regional studies would more closely approximate field research results. We assess the ability of a well-populated regional database collected in the southwestern Brazilian Amazon to reproduce expected biogeochemical trends associated with forest clearing and pasture establishment, and explore the ramifications of relying on independently collected soil data for regional modeling. The Soteron database includes analyses of approximately 3000 soil cores collected for zoning purposes in the state of Rondonia. Pasture ages were determined from a time series of Landsat TM images classified using spectral mixture analysis. Although regional averages showed some of the temporal trends expected based on field study results (e.g. increase in pH following forest clearing), the trends were not statistically significant. Stratification by precipitation and other variables showed pasture age to be important but difficult to separate from other potential controls on soil conditions, mainly because of the reduced number of observations in each stratum. Using multiple regression, which permitted the inclusion of all potential explanatory factors and interactions, pasture age was shown to be a statistically significant predictor of soil conditions. However, the expected temporal sequence of changes documented by field chronosequence studies could not be reproduced. Properties dominated by large-scale environmental gradients - pH, sum of base cations, aluminum saturation, and exchangeable calcium - were moderately well modeled, while those more strongly linked to dynamic spatially heterogeneous processes such as biological cycling and land management, particularly organic carbon and nitrogen, could not be modeled. Management-induced soil changes occur at too fine a scale to be captured by most maps, and the relative changes are small compared with spatial heterogeneity caused by controls on soil development over large regions. Therefore, regardless of whether chronosequence-derived models of biogeochemical response to land-cover change are correct, the results of these models will not lead to spatially explicit maps that can be validated by regional reconnaissance, nor will they facilitate realistic predictions of the regional biogeochemical consequences of land-cover change. The change from local to regional scale entails a change in the relative importance of processes controlling soil property behavior. | |||||
BibTeX:
@article{holmes_soil_2004, author = {Holmes, K. W. and Roberts, D. A. and Sweeney, S. and Numata, I. and Matricardi, E. and Biggs, T. W. and Batista, G. and Chadwick, O. A.}, title = {Soil databases and the problem of establishing regional biogeochemical trends}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {796--814}, url = {://WOS:000221421600019}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00753.x} } |
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Holm, J., Van Bloem, S., Larocque, G. and Shugart, H. | Shifts in biomass and productivity for a subtropical dry forest in response to simulated elevated hurricane disturbances [BibTeX] |
2017 | Environ. Res. Lett. Vol. 12, pp. 025007 |
article | |
BibTeX:
@article{holm_shifts_2017, author = {Holm, J.A. and Van Bloem, S.J. and Larocque, G.R. and Shugart, H.H.}, title = {Shifts in biomass and productivity for a subtropical dry forest in response to simulated elevated hurricane disturbances}, journal = {Environ. Res. Lett.}, year = {2017}, volume = {12}, pages = {025007} } |
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Holm, J.A., Knox, R.G., Zhu, Q., Fisher, R.A., Koven, C.D., Nogueira Lima, A.J., Riley, W.J., Longo, M., Negrón-Juárez, R.I., de Araujo, A.C., Kueppers, L.M., Moorcroft, P.R., Higuchi, N. and Chambers, J.Q. | The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models | 2020 | Journal of Geophysical Research: Biogeosciences Vol. 125(3), pp. e2019JG005500 |
article | DOI URL |
Abstract: Abstract There is large uncertainty whether Amazon forests will remain a carbon sink as atmospheric CO2 increases. Hence, we simulated an old-growth tropical forest using six versions of four terrestrial models differing in scale of vegetation structure and representation of biogeochemical (BGC) cycling, all driven with CO2 forcing from the preindustrial period to 2100. The models were benchmarked against tree inventory and eddy covariance data from a Brazilian site for present-day predictions. All models predicted positive vegetation growth that outpaced mortality, leading to continual increases in present-day biomass accumulation. Notably, the two vegetation demographic models (VDMs) (ED2 and ELM-FATES) always predicted positive stem diameter growth in all size classes. The field data, however, indicated that a quarter of canopy trees didn't grow over the 15-year period, and while high interannual variation existed, biomass change was near neutral. With a doubling of CO2, three of the four models predicted an appreciable biomass sink (0.77 to 1.24 Mg ha−1 year−1). ELMv1-ECA, the only model used here that includes phosphorus constraints, predicted the lowest biomass sink relative to initial biomass stocks (+21%), lower than the other BGC model, CLM5 (+48%). Models projections differed primarily through variations in nutrient constraints, then carbon allocation, initial biomass, and density-dependent mortality. The VDM's performance was similar or better than the BGC models run in carbon-only mode, suggesting that nutrient competition in VDMs will improve predictions. We demonstrate that VDMs are comparable to nondemographic (i.e., “big-leaf”) models but also include finer scale demography and competition that can be evaluated against field observations. | |||||
BibTeX:
@article{holm_central_2020, author = {Holm, Jennifer A. and Knox, Ryan G. and Zhu, Qing and Fisher, Rosie A. and Koven, Charles D. and Nogueira Lima, Adriano J. and Riley, William J. and Longo, Marcos and Negrón-Juárez, Robinson I. and de Araujo, Alessandro C. and Kueppers, Lara M. and Moorcroft, Paul R. and Higuchi, Niro and Chambers, Jeffrey Q.}, title = {The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models}, journal = {Journal of Geophysical Research: Biogeosciences}, year = {2020}, volume = {125}, number = {3}, pages = {e2019JG005500}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019JG005500}, doi = {https://doi.org/10.1029/2019JG005500} } |
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Holland, E.A., Neff, J.C., Townsend, A.R. and McKeown, B. | Uncertainties in the temperature sensitivity of decomposition in tropical and subtropical ecosystems: Implications for models | 2000 | Global Biogeochemical Cycles Vol. 14(4), pp. 1137-1151 |
article | DOI URL |
Abstract: Tropical ecosystems play a central role in the global carbon cycle. Large changes in tropical temperature over geologic time and the significant responses of tropical ecosystems to shorter-term variations such as El Nino/La Nina argue for a robust understanding of the temperature sensitivity of tropical decomposition. To examine the responsiveness of heterotrophic respiration to temperature, we measured rates of heterotrophic respiration from a wide range of tropical soils in a series ol laboratory incubations. Under conditions of optimal soil water and nonlimiting substrate availability, heterotrophic respiration rose exponentially with rising temperature. The mean Q(10) measured across all temperature ranges in these short-term incubations was 2.37, but there was significant variation in eros across sites. The source of this variation could not be explained by soil carbon or nitrogen content, soil texture, site climate, or lignin to nitrogen ratio. At the beginning of the incubation, heterotrophic respiration increased exponentially with temperature for all sites, despite the fact that the fluxes differed by an order of magnitude. When substrate availability became limiting later in the incubation, the temperature response changed, and heterotrophic response declined above 35 degreesC. The documented changes in temperature sensitivity with substrate availability argue for using temperature relationships developed under optimal conditions of substrate availability for models which include temperature regulation of heterotrophic respiration. To evaluate the significance of this natural variation in temperature control over decomposition, we used the Century ecosystem model gridded for the areas between the tropics of Cancer and Capricorn. These simulations used the mean and upper and lower confidence limits of the normalized exponential temperature response of our experimental studies. We found that systems with the lowest temperature sensitivity accumulated a total of 70 Pg more carbon in soil organic carbon and respired 5.5 Pg yr(-1) less carbon compared to the systems with the highest sensitivity. | |||||
BibTeX:
@article{holland_uncertainties_2000, author = {Holland, E. A. and Neff, J. C. and Townsend, A. R. and McKeown, B.}, title = {Uncertainties in the temperature sensitivity of decomposition in tropical and subtropical ecosystems: Implications for models}, journal = {Global Biogeochemical Cycles}, year = {2000}, volume = {14}, number = {4}, pages = {1137--1151}, url = {://WOS:000166341000012}, doi = {https://doi.org/10.1029/2000gb001264} } |
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Holben, B.N., Tanre, D., Smirnov, A., Eck, T.F., Slutsker, I., Abuhassan, N., Newcomb, W.W., Schafer, J.S., Chatenet, B., Lavenu, F., Kaufman, Y.J., Castle, J.V., Setzer, A., Markham, B., Clark, D., Frouin, R., Halthore, R., Karneli, A., O'Neill, N.T., Pietras, C., Pinker, R.T., Voss, K. and Zibordi, G. | An emerging ground-based aerosol climatology: Aerosol optical depth from AERONET | 2001 | Journal of Geophysical Research-Atmospheres Vol. 106(D11), pp. 12067-12097 |
article | DOI URL |
Abstract: Long-term measurements by the AERONET program of spectral aerosol optical depth, precipitable water, and derived Angstrom exponent were analyzed and compiled into an aerosol optical properties climatology. Quality assured monthly means are presented and described for 9 primary sites and 21 additional multiyear sites with distinct aerosol regimes representing tropical biomass burning, boreal forests, midlatitude humid climates, midlatitude dry climates, oceanic sites, desert sites, and background sites. Seasonal trends for each of these nine sites are discussed and climatic averages presented. | |||||
BibTeX:
@article{holben_emerging_2001, author = {Holben, B. N. and Tanre, D. and Smirnov, A. and Eck, T. F. and Slutsker, I. and Abuhassan, N. and Newcomb, W. W. and Schafer, J. S. and Chatenet, B. and Lavenu, F. and Kaufman, Y. J. and Castle, J. V. and Setzer, A. and Markham, B. and Clark, D. and Frouin, R. and Halthore, R. and Karneli, A. and O'Neill, N. T. and Pietras, C. and Pinker, R. T. and Voss, K. and Zibordi, G.}, title = {An emerging ground-based aerosol climatology: Aerosol optical depth from AERONET}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2001}, volume = {106}, number = {D11}, pages = {12067--12097}, url = {://WOS:000169300200027}, doi = {https://doi.org/10.1029/2001jd900014} } |
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Holanda, B.A., Pöhlker, M.L., Walter, D., Saturno, J., Sörgel, M., Ditas, J., Ditas, F., Schulz, C., Franco, M.A., Wang, Q., Donth, T., Artaxo, P., Barbosa, H.M.J., Borrmann, S., Braga, R., Brito, J., Cheng, Y., Dollner, M., Kaiser, J.W., Klimach, T., Knote, C., Krüger, O.O., Fütterer, D., Lavrič, J.V., Ma, N., Machado, L.A.T., Ming, J., Morais, F.G., Paulsen, H., Sauer, D., Schlager, H., Schneider, J., Su, H., Weinzierl, B., Walser, A., Wendisch, M., Ziereis, H., Zöger, M., Pöschl, U., Andreae, M.O. and Pöhlker, C. | Influx of African biomass burning aerosol during the Amazonian dry season through layered transatlantic transport of black carbon-rich smoke [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(8), pp. 4757-4785 |
article | DOI URL |
BibTeX:
@article{holanda_influx_2020, author = {Holanda, B. A. and Pöhlker, M. L. and Walter, D. and Saturno, J. and Sörgel, M. and Ditas, J. and Ditas, F. and Schulz, C. and Franco, M. A. and Wang, Q. and Donth, T. and Artaxo, P. and Barbosa, H. M. J. and Borrmann, S. and Braga, R. and Brito, J. and Cheng, Y. and Dollner, M. and Kaiser, J. W. and Klimach, T. and Knote, C. and Krüger, O. O. and Fütterer, D. and Lavrič, J. V. and Ma, N. and Machado, L. A. T. and Ming, J. and Morais, F. G. and Paulsen, H. and Sauer, D. and Schlager, H. and Schneider, J. and Su, H. and Weinzierl, B. and Walser, A. and Wendisch, M. and Ziereis, H. and Zöger, M. and Pöschl, U. and Andreae, M. O. and Pöhlker, C.}, title = {Influx of African biomass burning aerosol during the Amazonian dry season through layered transatlantic transport of black carbon-rich smoke}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {8}, pages = {4757--4785}, url = {https://acp.copernicus.org/articles/20/4757/2020/}, doi = {https://doi.org/10.5194/acp-20-4757-2020} } |
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Holanda, B.A., Franco, M.A., Walter, D., Artaxo, P., Carbone, S., Cheng, Y., Chowdhury, S., Ditas, F., Gysel-Beer, M., Klimach, T., Kremper, L.A., Krüger, O.O., Lavric, J.V., Lelieveld, J., Ma, C., Machado, L.A.T., Modini, R.L., Morais, F.G., Pozzer, A., Saturno, J., Su, H., Wendisch, M., Wolff, S., Pöhlker, M.L., Andreae, M.O., Pöschl, U. and Pöhlker, C. | African biomass burning affects aerosol cycling over the Amazon | 2023 | Communications Earth & Environment Vol. 4(1), pp. 154 |
article | DOI URL |
Abstract: Smoke from vegetation fires affects air quality, atmospheric cycling, and the climate in the Amazon rain forest. A major unknown has remained the quantity of long-range transported smoke from Africa in relation to local and regional fire emissions. Here we quantify the abundance, seasonality, and properties of African smoke in central Amazonia. We show that it accounts for textasciitilde 60% of the black carbon concentrations during the wet season and textasciitilde 30% during the dry season. The African smoke influences aerosol-radiation interactions across the entire Amazon, with the strongest impact on the vulnerable eastern basin, a hot spot of climate and land use change. Our findings further suggest that the direct influence of African smoke has been historically relevant for soil fertilization, the carbon and water cycles, and, thus, the development of the Amazon forest ecosystem, even in the pre-industrial era. | |||||
BibTeX:
@article{holanda_african_2023, author = {Holanda, Bruna A. and Franco, Marco A. and Walter, David and Artaxo, Paulo and Carbone, Samara and Cheng, Yafang and Chowdhury, Sourangsu and Ditas, Florian and Gysel-Beer, Martin and Klimach, Thomas and Kremper, Leslie A. and Krüger, Ovid O. and Lavric, Jost V. and Lelieveld, Jos and Ma, Chaoqun and Machado, Luiz A. T. and Modini, Robin L. and Morais, Fernando G. and Pozzer, Andrea and Saturno, Jorge and Su, Hang and Wendisch, Manfred and Wolff, Stefan and Pöhlker, Mira L. and Andreae, Meinrat O. and Pöschl, Ulrich and Pöhlker, Christopher}, title = {African biomass burning affects aerosol cycling over the Amazon}, journal = {Communications Earth & Environment}, year = {2023}, volume = {4}, number = {1}, pages = {154}, url = {https://doi.org/10.1038/s43247-023-00795-5}, doi = {https://doi.org/10.1038/s43247-023-00795-5} } |
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Hogan, D.J., D’Antona, Á.d.O. and Carmo, R.L.d. | Dinâmica Demográfica Recente da Amazônia [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 71-116 |
incollection | |
BibTeX:
@incollection{batistella_dinamica_2008, author = {Hogan, Daniel Joseph and D’Antona, Álvaro de O. and Carmo, Roberto Luiz do}, title = {Dinâmica Demográfica Recente da Amazônia}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {71--116}, note = {Section: 2} } |
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Hofhansl, F., Andersen, K., Fleischer, K., Fuchslueger, L., Ramming, A., Schaap, K., Valverde-Barrantes, O. and Lapola, D. | Amazon forest ecosystem responses to elevated atmospheric CO2 and alterations in nutrient availability: filling the gaps with model-experiment integration [BibTeX] |
2016 | Frontiers: Earth Science Research Topics Vol. 4(19) |
article | DOI |
BibTeX:
@article{hofhansl_amazon_2016, author = {Hofhansl, F. and Andersen, K.M. and Fleischer, K. and Fuchslueger, L. and Ramming, A. and Schaap, K. and Valverde-Barrantes, O.J. and Lapola, D.}, title = {Amazon forest ecosystem responses to elevated atmospheric CO2 and alterations in nutrient availability: filling the gaps with model-experiment integration}, journal = {Frontiers: Earth Science Research Topics}, year = {2016}, volume = {4}, number = {19}, doi = {https://doi.org/10.3389/feart.2016.00019} } |
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Hoffer, A., Gelencser, A., Guyon, P., Kiss, G., Schmid, O., Frank, G.P., Artaxo, P. and Andreae, M.O. | Optical properties of humic-like substances (HULIS) in biomass-burning aerosols | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 3563-3570 |
article | URL |
Abstract: We present here the optical properties of humic-like substances (HULIS) isolated from the fine fraction of biomass-burning aerosol collected in the Amazon basin during the LBA-SMOCC ( Large scale Biosphere atmosphere experiment in Amazonia - SMOke aerosols, Clouds, rainfall and Climate) experiment in September 2002. From the isolated HULIS, aerosol particles were generated and their scattering and absorption coefficients measured. The size distribution and mass of the particles were also recorded. The value of the index of refraction was derived from "closure" calculations based on particle size, scattering and absorption measurements. On average, the complex index of refraction at 532 nm of HULIS collected during day and nighttime was 1.65 - 0.0019i and 1.69 - 0.0016i, respectively. In addition, the imaginary part of the complex index of refraction was calculated using the measured absorption coefficient of the bulk HULIS. The mass absorption coefficient of the HULIS at 532 nm was found to be quite low (0.031 and 0.029 m(2) g(-1) for the day and night samples, respectively). However, due to the high absorption Angstrom exponent ( 6 - 7) of HULIS, the specific absorption increases substantially towards shorter wavelengths ( similar to 2-3 m(2) g(-1) at 300 nm), causing a relatively high ( up to 50%) contribution to the light absorption of our Amazonian aerosol at 300 nm. For the relative contribution of HULIS to light absorption in the entire solar spectrum, lower values (6.4 - 8.6%) are obtained, but those are still not negligible. | |||||
BibTeX:
@article{hoffer_optical_2006, author = {Hoffer, A. and Gelencser, A. and Guyon, P. and Kiss, G. and Schmid, O. and Frank, G. P. and Artaxo, P. and Andreae, M. O.}, title = {Optical properties of humic-like substances (HULIS) in biomass-burning aerosols}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {3563--3570}, url = {://WOS:000240205400004} } |
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Hoffer, A., Gelencser, A., Blazso, M., Guyon, P., Artaxo, P. and Andreae, M.O. | Diel and seasonal variations in the chemical composition of biomass burning aerosol | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 3505-3515 |
article | URL |
Abstract: Fine aerosol particles were collected separately during daytime and nighttime at a tropical pasture site in Rondonia, Brazil, during the burning and dry-to-wet transition period in 2002. Total carbon (TC) and water-soluble organic carbon (WSOC) were measured by evolved gas analysis (EGA). Based on the thermochemical properties of the fine aerosol, the relative amounts of the volatile and refractory compounds were estimated. It was found that the thermally refractory (possibly higher molecular weight) compounds dominated the TC composition. Their contribution to TC was higher in the daytime than in the nighttime samples. The relative share of WSOC also showed a statistically significant diel variation as did its refractory fraction. Anhydrosugars and phenolic acids were determined by GC-MS and their diel variation was studied. Based on the decrease of their relative concentrations between the biomass burning and transition periods and their distinctly different diel variations, we suggest that the phenolic acids may undergo chemical transformations in the aerosol phase, possibly towards more refractory compounds (humic-like substances, HULIS), as has been suggested previously. These conclusions are supported by the results of the thermally assisted hydrolysis and methylation gas chromatography-mass spectrometry of the same filter samples. | |||||
BibTeX:
@article{hoffer_diel_2006, author = {Hoffer, A. and Gelencser, A. and Blazso, M. and Guyon, P. and Artaxo, P. and Andreae, M. O.}, title = {Diel and seasonal variations in the chemical composition of biomass burning aerosol}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {3505--3515}, url = {://WOS:000240024600002} } |
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Hoelzemann, J.J., Longo, K.M., Fonseca, R.M., do Rosario, N.M.E., Elbern, H., Freitas, S.R. and Pires, C. | Regional representativity of AERONET observation sites during the biomass burning season in South America determined by correlation studies with MODIS Aerosol Optical Depth | 2009 | Journal of Geophysical Research-Atmospheres Vol. 114 |
article | DOI URL |
Abstract: This paper presents an analysis of ground-based Aerosol Optical Depth (AOD) observations by the Aerosol Robotic Network (AERONET) in South America from 2001 to 2007 in comparison with the satellite AOD product of Moderate Resolution Imaging Spectroradiometer (MODIS), aboard TERRA and AQUA satellites. Data of 12 observation sites were used with primary interest in AERONET sites located in or downwind of areas with high biomass burning activity and with measurements available for the full time range. Fires cause the predominant carbonaceous aerosol emission signal during the dry season in South America and are therefore a special focus of this study. Interannual and seasonal behavior of the observed AOD at different sites were investigated, showing clear differences between purely fire and urban influenced sites. An intercomparison of AERONET and MODIS AOD annual correlations revealed that neither an interannual long-term trend may be observed nor that correlations differ significantly owing to different overpass times of TERRA and AQUA. Individual anisotropic representativity areas for each AERONET site were derived by correlating daily AOD of each site for all years with available individual MODIS AOD pixels gridded to 1 degrees x 1 degrees. Results showed that for many sites a good AOD correlation (R(2) textgreater 0.5) persists for large, often strongly anisotropic, areas. The climatological areas of common regional aerosol regimes often extend over several hundreds of kilometers, sometimes far across national boundaries. As a practical application, these strongly inhomogeneous and anisotropic areas of influence are being implemented in the tropospheric aerosol data assimilation system of the Coupled Chemistry-Aerosol-Tracer Transport Model coupled to the Brazilian Regional Atmospheric Modeling System (CCATT-BRAMS) at the Brazilian National Institute for Space Research (INPE). This new information promises an improved exploitation of local site sampling and, thus, chemical weather forecast. | |||||
BibTeX:
@article{hoelzemann_regional_2009, author = {Hoelzemann, Judith J. and Longo, Karla M. and Fonseca, Rafael M. and do Rosario, Nilton M. E. and Elbern, Hendrik and Freitas, Saulo R. and Pires, Carlos}, title = {Regional representativity of AERONET observation sites during the biomass burning season in South America determined by correlation studies with MODIS Aerosol Optical Depth}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2009}, volume = {114}, url = {://WOS:000267643000001}, doi = {https://doi.org/10.1029/2008jd010369} } |
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Hodnett, M.G. and Tomasella, J. | Marked differences between van Genuchten soil water-retention parameters for temperate and tropical soils: a new water-retention pedo-transfer functions developed for tropical soils | 2002 | Geoderma Vol. 108(3-4), pp. 155-180 |
article | DOI URL |
Abstract: All of the physical, chemical and soil water-retention data suitable for the derivation of a Pedo-Transfer Functions (PTF) for water retention for tropical soils (771 suitable horizons) were extracted from the IGBP-DIS soil database. The parameters theta(s), theta(r), alpha and n of the van Genuchten (vG) [Soil Sci. Soc. Am. J. 44 (1980) 892] equation were derived and compared with parameter values from two published data sets of temperate region soils. Thirty-five percent of the soils in the tropical (IGBP/T) database were classified as clays, compared with only 4% and 7% in the temperate databases. The IGBP/T soil bulk densities were significantly lower (ptextless0.001) for nine textural classes. For the more clayey textural classes, the value of α was higher for the IGBP/T soils, implying more large pores and more structure. For kaolinitic soils in the IGBP/T database, α was typically around 0.4 kPa(-1) compared with 0.04 kPa(-1) for montmorillonitic soils. Mineralogy is clearly important and should be included in PTFs (if available). The value of n for clay soils in the IGBP/T data set was significantly higher than for temperate soils, and θ(s) was significantly higher for nine textural classes (p textless 0.001) reflecting their lower bulk density. theta(r) was also significantly higher for all textural classes except sand. For clay, the mean value of theta(r) was 0.27 m(3) m(-3), compared to only 0.11 m(3) m(-3) for temperate soils. For 17% of the IGBP/T data, theta(r) exceeded 0.3 m(3) m(-3), a value often used as a fitting constraint. A tropical soil PTF was developed using multiple regression techniques. This predicted water-retention curves more reliably than either class PTFs or "soil class" PTFs, but was not reliable for low-density soils such as Andosols. The IGBP/T data set includes some groups of soils, e.g., Andosols and Ferralsols, whose properties are extremely different from those of most temperate soils. These differences emphasise the need to develop separate PTFs for tropical soils, or perhaps for specific groups of soils. There were few water-retention data from below 1.5-m depth and a complete lack of hydraulic conductivity data in the IGBP/T database. This is a major impediment to the modelling of water movement and uptake in deep-rooted ecosystems, for example, tropical forest and savannah. (C) 2002 Elsevier Science B.V All rights reserved. | |||||
BibTeX:
@article{hodnett_marked_2002, author = {Hodnett, M. G. and Tomasella, J.}, title = {Marked differences between van Genuchten soil water-retention parameters for temperate and tropical soils: a new water-retention pedo-transfer functions developed for tropical soils}, journal = {Geoderma}, year = {2002}, volume = {108}, number = {3-4}, pages = {155--180}, url = {://WOS:000177024600001}, doi = {https://doi.org/10.1016/s0016-7061(02)00105-2} } |
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Hirsch, A.I., Little, W.S., Houghton, R.A., Scott, N.A. and White, J.D. | The net carbon flux due to deforestation and forest re-growth in the Brazilian Amazon: analysis using a process-based model | 2004 | Global Change Biology Vol. 10(5), pp. 908-924 |
article | DOI URL |
Abstract: We developed a process-based model of forest growth, carbon cycling and land-cover dynamics named CARLUC (for CARbon and Land-Use Change) to estimate the size of terrestrial carbon pools in terra firme (nonflooded) forests across the Brazilian Legal Amazon and the net flux of carbon resulting from forest disturbance and forest recovery from disturbance. Our goal in building the model was to construct a relatively simple ecosystem model that would respond to soil and climatic heterogeneity that allows us to study the impact of Amazonian deforestation, selective logging and accidental fire on the global carbon cycle. This paper focuses on the net flux caused by deforestation and forest re-growth over the period from 1970 to 1998. We calculate that the net flux to the atmosphere during this period reached a maximum of similar to0.35 PgC yr(-1) (1 PgC= 1 x 10(15) gC) in 1990, with a cumulative release of similar to7 PgC from 1970 to 1998. The net flux is higher than predicted by an earlier study (Houghton et al., 2000) by a total of 1 PgC over the period 1989-1998 mainly because CARLUC predicts relatively high mature forest carbon storage compared with the datasets used in the earlier study. Incorporating the dynamics of litter and soil carbon pools into the model increases the cumulative net flux bysimilar to1 PgC from 1970 to 1998, while different assumptions about land-cover dynamics only caused small changes. The uncertainty of the net flux, calculated with a Monte-Carlo approach, is roughly 35% of the mean value (1 SD). | |||||
BibTeX:
@article{hirsch_net_2004, author = {Hirsch, A. I. and Little, W. S. and Houghton, R. A. and Scott, N. A. and White, J. D.}, title = {The net carbon flux due to deforestation and forest re-growth in the Brazilian Amazon: analysis using a process-based model}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {908--924}, url = {://WOS:000221421600027}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00765.x} } |
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Hilker, T., Galvão, L.S., Aragão, L.E., Moura, Y.M.d., Amaral, C.H.d., Lyapustin, A.I., Wu, J., Albert, L.P., José Ferreira, M., Liana O. Anderson, Victor A.H.F. dos Santos, Neill Prohaska, Edgard Tribuzy, João Vitor Barbosa Ceron, Scott R. Saleska, Yujie Wang, José Francisco de Carvalho Gonçalves, Raimundo Cosme de Oliveira Junior, João Victor Figueiredo Cardoso Rodrigues and Garcia, M.N. | Vegetation chlorophyll estimates in the Amazon from multi-angle MODIS observations and canopy reflectance model [BibTeX] |
2017 | International Journal of Applied Earth Observation and Geoinformation Vol. 58, pp. 278-287 |
article | |
BibTeX:
@article{hilker_vegetation_2017, author = {Hilker, Thomas and Galvão, Lênio Soares and Aragão, Luiz E.O.C. and Moura, Yhasmin M. de and Amaral, Cibele H. do and Lyapustin, Alexei I. and Wu, Jin and Albert, Loren P. and José Ferreira, Marciel and Liana O. Anderson and Victor A.H.F. dos Santos and Neill Prohaska and Edgard Tribuzy and João Vitor Barbosa Ceron and Scott R. Saleska and Yujie Wang and José Francisco de Carvalho Gonçalves and Raimundo Cosme de Oliveira Junior and João Victor Figueiredo Cardoso Rodrigues and Garcia, Maquelle Neves}, title = {Vegetation chlorophyll estimates in the Amazon from multi-angle MODIS observations and canopy reflectance model}, journal = {International Journal of Applied Earth Observation and Geoinformation}, year = {2017}, volume = {58}, pages = {278--287} } |
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Higuchi, N., Suwa, R., Higuchi, F.G., Lima, A.J.N. and Santos, J.d. | Overview of Forest Carbon Stocks Study in Amazonas State, Brazil [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 171-187 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_overview_2016, author = {Higuchi, Niro and Suwa, Rempei and Higuchi, Francisco G. and Lima, Adriano J. N. and Santos, Joaquim dos}, title = {Overview of Forest Carbon Stocks Study in Amazonas State, Brazil}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {171--187}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Hess, L.L., Novo, E., Slaymaker, D.M., Holt, J., Steffen, C., Valeriano, D.M., Mertes, L.A.K., Krug, T., Melack, J.M., Gastil, M., Holmes, C. and Hayward, C. | Geocoded digital videography for validation of land cover mapping in the Amazon basin | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1527-1555 |
article | DOI URL |
Abstract: Four Validation Overflights for Amazon Mosaics (VOAM) aerial video surveys have been carried out in the Brazilian Amazon to provide ground verification for mapping of wetland cover with the Global Rain Forest Mapping (GRFM) Project JERS-1 (Japanese Earth Remote Sensing Satellite) mosaics of the Amazon basin. Surveys in 1995 and 1996, acquired with handheld analog camcorders from small aircraft, were timed to imaging of the GRFM low- and high-water mosaics, and limited to within 600 km of Manaus. For the 1997 and 1999 flights, digital camcorder systems were installed in the Bandeirante survey plane operated by Brazil's National Institute for Space Research. The VOAM97 and VOAM99 surveys circumscribed the Brazilian Amazon, documenting ground conditions at resolutions on the order of 1 m (wide-angle format) and 10 cm (zoom format) for wetlands, forests, savannas, and human-impacted areas. Global Positioning System (GPS) information encoded on the video audio track was extracted by mosaicking software that automatically generates geocoded digital mosaics from video clips. On the 1999 survey, a laser altimeter recorded profiles of terrain and vegetation canopy heights. A validation dataset was compiled from the videography for a portion of the GRFM mosaics extending 6degrees by 4degrees in longitude and latitude, using randomly selected points along flight lines. Other applications of the VOAM videography include acquisition of ground control points for image geolocation, creation of a high-resolution geocoded mosaic of a forest study area, forest biomass estimation, and rapid assessment of fire damage. Geocoded digital videography provides a cost-effective means of compiling high-resolution validation datasets for land cover mapping in remote, cloud-covered regions. | |||||
BibTeX:
@article{hess_geocoded_2002, author = {Hess, L. L. and Novo, Emlm and Slaymaker, D. M. and Holt, J. and Steffen, C. and Valeriano, D. M. and Mertes, L. A. K. and Krug, T. and Melack, J. M. and Gastil, M. and Holmes, C. and Hayward, C.}, title = {Geocoded digital videography for validation of land cover mapping in the Amazon basin}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1527--1555}, url = {://WOS:000174661900018}, doi = {https://doi.org/10.1080/01431160110092687} } |
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Hess, L.L., Melack, J.M., Novo, E., Barbosa, C.C.F. and Gastil, M. | Dual-season mapping of wetland inundation and vegetation for the central Amazon basin | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 404-428 |
article | DOI URL |
Abstract: Wetland extent was mapped for the central Amazon region, using mosaicked L-band synthetic aperture radar (SAR) imagery acquired by the Japanese Earth Resources Satellite-L For the wetland portion of the 18 x 8degrees study area, dual-season radar mosaics were used to map inundation extent and vegetation under both low-water and high-water conditions at 100-m resolution, producing the first high-resolution wetlands map for the region. Thematic accuracy of the mapping was assessed using high-resolution digital videography acquired during two aerial surveys of the Brazilian Amazon. A polygon-based segmentation and clustering was used to delineate wetland extent with an accuracy of 95%. A pixel-based classifier was used to map wetland vegetation and flooding state based on backscattering coefficients of two-season class combinations. Producer's accuracy for flooded and nonflooded forest classes ranged from 78% to 91%, with lower accuracy (63-65%) for flooded herbaceous vegetation. Seventeen percent of the study quadrat was occupied by wetlands, which were 96% inundated at high water and 26% inundated at low water. Flooded forest constituted nearly 70% of the entire wetland area at high water, but there are large regional variations in the proportions of wetland habitats. The SAR-based mapping provides a basis for improved estimates of the contribution of wetlands to biogeochemical and hydrological processes in the Amazon basin, a key question in the Large-Scale Biosphere-Atmosphere Experiment in Amazonia. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{hess_dual-season_2003, author = {Hess, L. L. and Melack, J. M. and Novo, Emlm and Barbosa, C. C. F. and Gastil, M.}, title = {Dual-season mapping of wetland inundation and vegetation for the central Amazon basin}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {404--428}, url = {://WOS:000186827400003}, doi = {https://doi.org/10.1016/j.rse.2003.04.001} } |
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Hess, L.L., Melack, J.M., Affonso, A.G., Barbosa, C., Gastil-Buhl, M. and Novo, E.M.L.M. | Wetlands of the Lowland Amazon Basin: Extent, Vegetative Cover, and Dual-season Inundated Area as Mapped with JERS-1 Synthetic Aperture Radar [BibTeX] |
2015 | Wetlands Vol. 35, pp. 745-756 |
article | DOI |
BibTeX:
@article{hess_wetlands_2015, author = {Hess, Laura L. and Melack, John M. and Affonso, Adriana G. and Barbosa, Claudio and Gastil-Buhl, Mary and Novo, Evlyn M. L. M.}, title = {Wetlands of the Lowland Amazon Basin: Extent, Vegetative Cover, and Dual-season Inundated Area as Mapped with JERS-1 Synthetic Aperture Radar}, journal = {Wetlands}, year = {2015}, volume = {35}, pages = {745--756}, doi = {https://doi.org/10.1007/s13157-015-0666-y} } |
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Herpin, U., Cerri, C.C., Carvalho, M.C.S., Markert, B., Enzweiler, J., Friese, K. and Breulmann, G. | Biogeochemical dynamics following land use change from forest to pasture in a humid tropical area (Rondonia, Brazil): a multi-element approach by means of XRF-spectroscopy | 2002 | Science of the Total Environment Vol. 286(1-3), pp. 97-109 |
article | DOI URL |
Abstract: Forest burning for pastures in tropical areas represents an important component of biogeochemical cycles. In order to provide information concerning chemical modifications after forest burning, in this local study the total contents of 29 elements in topsoils were analyzed when forest is changed to pasture land. The work was carried out in 1999 in Rondonia state (Brazilian Amazon Basin) focussing on a native forest site and four neighboring pastures established in 1987, 1983, 1972 and 1911 after forest conversion. Chemical fingerprint graphs of the pasture soils related to the forest soil illustrated mainly higher contents for the vast majority of macro- and micro nutrients, but for other elements as well (e.g. Ba, Sr, Cr, Ni, V or Pb). Also increases of pH levels were measured in all pastures, which remained higher than the forest values for decades. After initial increases of most of the elements in pasture of 1987 the decreases of some macro elements (e.g. C, N, K, Mg, S) in pasture 1983 as well as again the enhanced levels in pasture 1972 and 1911 suggest both a persistent leaching of these elements and a function of pasture age where external element inputs exceed outputs. Ash deposition, accumulation of organic matter, animal excreta as well as natural soil conditions are discussed as influencing factors on the element contents of the original forest and the pasture soils. Nevertheless. in this particular area continuous pasturing after forest clearing primarily enriched the soils in elements. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{herpin_biogeochemical_2002, author = {Herpin, U. and Cerri, C. C. and Carvalho, M. C. S. and Markert, B. and Enzweiler, J. and Friese, K. and Breulmann, G.}, title = {Biogeochemical dynamics following land use change from forest to pasture in a humid tropical area (Rondonia, Brazil): a multi-element approach by means of XRF-spectroscopy}, journal = {Science of the Total Environment}, year = {2002}, volume = {286}, number = {1-3}, pages = {97--109}, url = {://WOS:000174076300009}, doi = {https://doi.org/10.1016/s0048-9697(01)00967-6} } |
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Herdies, D.L., da Silva, A., Dias, M. and Ferreira, R.N. | Moisture budget of the bimodal pattern of the summer circulation over South America | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Submonthly variations in warm-season (January-February) precipitation over South America, in particular over the Amazon basin, central southwest Brazil, north Argentina, and Paraguay are studied. Two distinct regimes of lower tropospheric winds (westerlies and easterlies) were observed in Rondonia during the Wet Season Atmospheric Mesoscale Campaign (WETAMC) component of the Large-Scale Atmosphere-Biosphere Experiment in Amazonia (LBA) and the Tropical Rainfall Measuring Mission (TRMM) field campaign. The westerly (easterly) winds were associated with strong (weak) convective activity over the South Atlantic Convergence Zone (SACZ). The period of this study (January and February of 1999) was divided into SACZ and no SACZ (NSACZ) regimes. The vertically integrated moisture fluxes over South America obtained from the National Aeronautics and Space Administration/Goddard Data Assimilation Office (NASA/DAO) assimilation system show that during the SACZ (NSACZ) period, strong (weak) convergence occurred over the Amazon basin with divergence (convergence) over southwestern Brazil, northern Argentina, and Paraguay. These moisture budgets also indicated that moisture transport from the tropics to the extratropics in the South American sector occurs more efficiently during the SACZ regime than during the NSACZ regime. | |||||
BibTeX:
@article{herdies_moisture_2002, author = {Herdies, D. L. and da Silva, A. and Dias, Mafs and Ferreira, R. N.}, title = {Moisture budget of the bimodal pattern of the summer circulation over South America}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200036}, doi = {https://doi.org/10.1029/2001jd000997} } |
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Herbert, D.A., Williams, M. and Rastetter, E.B. | A model analysis of N and P limitation on carbon accumulation in Amazonian secondary forest after alternate land-use abandonment | 2003 | Biogeochemistry Vol. 65(1), pp. 121-150 |
article | DOI URL |
Abstract: Productivity and carbon (C) storage in many mature tropical forests are considered phosphorus (P) limited because of advanced soil weathering. However, disturbance can shift limitation away from P and toward nitrogen (N) because of disproportionately large N losses associated with its mobility relative to P in ecosystems. This shift was illustrated by model analyses in which large disturbances including timber extraction and slash-burn were simulated in a P-limited tropical forest. Re-accumulation of ecosystem C during secondary forest growth was initially N-limited, but long term limitation reverted to P. Mechanisms controlling shifts between N and P limitation included: (1) N volatility during slash combustion produced ash that increased soil solution P more than N, (2) a wide N: P ratio in residual fuel and belowground necromass relative to soil organic matter (SOM) N: P produced a simultaneous P sink and N source during decomposition, (3) a supplemental ( to aerosol deposition) external N source via biological N fixation. Redistribution of N and P from low C: nutrient SOM to high C: nutrient vegetation was the most important factor contributing to the resilience of ecosystem C accumulation during secondary growth. Resilience was diminished when multiple harvest and re-growth cycles depleted SOM. Phosphorus losses in particular resulted in long-term reductions of C storage capacity because of slow re-supply rates via deposition and the absence of other external sources. Sensitivity analyses limiting the depth of microbially active SOM in soil profiles further illustrated the importance of elements stored in SOM to ecosystem resilience, pointing to a need for better knowledge on the functioning of deeply buried SOM. | |||||
BibTeX:
@article{herbert_model_2003, author = {Herbert, D. A. and Williams, M. and Rastetter, E. B.}, title = {A model analysis of N and P limitation on carbon accumulation in Amazonian secondary forest after alternate land-use abandonment}, journal = {Biogeochemistry}, year = {2003}, volume = {65}, number = {1}, pages = {121--150}, url = {://WOS:000185795900007}, doi = {https://doi.org/10.1023/a:1026020210887} } |
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Henkes, A., Fisch, G., Machado, L.A.T. and Chaboureau, J.P. | Morning boundary layer conditions for shallow to deep convective cloud evolution during the dry season in the central Amazon [BibTeX] |
2021 | Atmos. Chem. Phys. Vol. 21(17), pp. 13207-13225 |
article | DOI URL |
BibTeX:
@article{henkes_morning_2021, author = {Henkes, A. and Fisch, G. and Machado, L. A. T. and Chaboureau, J. P.}, title = {Morning boundary layer conditions for shallow to deep convective cloud evolution during the dry season in the central Amazon}, journal = {Atmos. Chem. Phys.}, year = {2021}, volume = {21}, number = {17}, pages = {13207--13225}, url = {https://acp.copernicus.org/articles/21/13207/2021/}, doi = {https://doi.org/10.5194/acp-21-13207-2021} } |
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Helmer, E.H., Lefsky, M.A. and Roberts, D.A. | Biomass accumulation rates of Amazonian secondary forest and biomass of old-growth forests from Landsat time series and the Geoscience Laser Altimeter System | 2009 | Journal of Applied Remote Sensing Vol. 3 |
article | DOI URL |
Abstract: We estimate the age of humid lowland tropical forests in Rondonia, Brazil, from a somewhat densely spaced time series of Landsat images (1975-2003) with an automated procedure, the Threshold Age Mapping Algorithm (TAMA), first described here. We then estimate a landscape-level rate of aboveground woody biomass accumulation of secondary forest by combining forest age mapping with biomass estimates from the Geoscience Laser Altimeter System (GLAS). Though highly variable, the estimated average biomass accumulation rate of 8.4 Mg ha(-1) yr(-1) agrees well with ground-based studies for young secondary forests in the region. In isolating the lowland forests, we map land cover and general types of old-growth forests with decision tree classification of Landsat imagery and elevation data. We then estimate aboveground live biomass for seven classes of old-growth forest. TAMA is simple, fast, and self-calibrating. By not using between-date band or index differences or trends, it requires neither image normalization nor atmospheric correction. In addition, it uses an approach to map forest cover for the self-calibrations that is novel to forest mapping with satellite imagery; it maps humid secondary forest that is difficult to distinguish from old-growth forest in single-date imagery; it does not assume that forest age equals time since disturbance; and it incorporates Landsat Multispectral Scanner (MSS) imagery. Variations on the work that we present here can be applied to other forested landscapes. Applications that use image time series will be helped by the free distribution of coregistered Landsat imagery, which began in December 2008, and of the Ice Cloud and land Elevation Satellite (ICESat) Vegetation Product, which simplifies the use of GLAS data. Finally, we demonstrate here for the first time how the optical imagery of fine spatial resolution that is viewable on Google Earth provides a new source of reference data for remote sensing applications related to land cover. | |||||
BibTeX:
@article{helmer_biomass_2009, author = {Helmer, Eileen H. and Lefsky, Michael A. and Roberts, Dar A.}, title = {Biomass accumulation rates of Amazonian secondary forest and biomass of old-growth forests from Landsat time series and the Geoscience Laser Altimeter System}, journal = {Journal of Applied Remote Sensing}, year = {2009}, volume = {3}, url = {://WOS:000271867800001 http://remotesensing.spiedigitallibrary.org/article.aspx?articleid=1028772}, doi = {https://doi.org/10.1117/1.3082116} } |
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Helliker, B.R., Berry, J.A., Betts, A.K., Bakwin, P.S., Davis, K.J., Denning, A.S., Ehleringer, J.R., Miller, J.B., Butler, M.P. and Ricciuto, D.M. | Estimates of net CO(2) flux by application of equilibrium boundary layer concepts to CO(2) and water vapor measurements from a tall tower | 2004 | Journal of Geophysical Research-Atmospheres Vol. 109(D20) |
article | DOI URL |
Abstract: [ 1] Convective turbulence within the atmospheric boundary layer (ABL) and movement of the ABL over the surface results in a large spatial (10(4) - 10(5) km(2)) integration of surface fluxes that affects the CO(2) and water vapor mixing ratios. We apply quasi-equilibrium concepts for the terrestrial ABL to measurements of CO(2) and water vapor made within the ABL from a tall tower (396 m) in Wisconsin. We suppose that CO(2) and water vapor mixing ratios in the ABL approach an equilibrium on timescales longer than a day: a balance between the surface fluxes and the exchange with the free troposphere above. By using monthly averaged ABL-to-free-tropospheric water vapor differences and surface water vapor flux, realistic estimates of vertical velocity exchange with the free troposphere can be obtained. We then estimated the net surface flux of CO(2) on a monthly basis for the year of 2000, using ABL-to-free-tropospheric CO(2) differences, and our flux difference estimate of the vertical exchange. These ABL-scale estimates of net CO(2) flux gave close agreement with eddy covariance measurements. Considering the large surface area which affects scalars in the ABL over synoptic timescales, the flux difference approach presented here could potentially provide regional-scale estimates of net CO(2) flux. | |||||
BibTeX:
@article{helliker_estimates_2004, author = {Helliker, B. R. and Berry, J. A. and Betts, A. K. and Bakwin, P. S. and Davis, K. J. and Denning, A. S. and Ehleringer, J. R. and Miller, J. B. and Butler, M. P. and Ricciuto, D. M.}, title = {Estimates of net CO(2) flux by application of equilibrium boundary layer concepts to CO(2) and water vapor measurements from a tall tower}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2004}, volume = {109}, number = {D20}, url = {://WOS:000224876600002}, doi = {https://doi.org/10.1029/2004jd004532} } |
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Hedges, J.I., Mayorga, E., Tsamakis, E., McClain, M.E., Aufdenkampe, A., Quay, P., Richey, J.E., Benner, R., Opsahl, S., Black, B., Pimentel, T., Quintanilla, J. and Maurice, L. | Organic matter in Bolivian tributaries of the Amazon River: A comparison to the lower mainstream | 2000 | Limnology and Oceanography Vol. 45(7), pp. 1449-1466 |
article | URL |
Abstract: We determined the concentrations and compositions of coarse particulate (textgreater63 mum). fine particulate (0.1-63 mum), and dissolved (0.001-0.1 mum) organic matter collected along a river reach extending from a first-order stream in the Bolivian Andes, through the Beni River system, to the lower Madeira and Amazon Rivers. Dissolved organic carbon (DOC) concentrations increased down the total reach from similar to 80 to 350 muM. The percentage of total DOC with a molecular weight greater than similar to1,000 atomic mass units that could be isolated by ultrafiltration also increased downstream from 40 to 80%. Weight percentages of organic carbon in the ultrafiltered isolates also grew downstream from 5% at the uppermost station to 37% in the Amazon mainstem. Organic carbon composed only 0.4-1.2 weight percentage of the total mass of the fine particulate fraction, which accounted for 70-80% of the total organic carbon (TOC) in transport through the highly turbid (similar to 600-2000 mg L-l) Beni sequence. Observed compositional differences were related primarily to the size fractions in which the organic matter occurred. On average, coarse particulate organic material exhibited an atomic C:N of 24, whereas ultrafiltered DOM was nitrogen poor, (C:N)a = 34, and fine particulate material was nitrogen rich, (C:N)a = 15. The lignin and stable-carbon isotopic compositions of these fractions indicate tree leaves and other nonwoody tissues from C3 land plants as predominant sources. Three molecular parameters demonstrate that the coarse, fine, and dissolved fractions of individual water samples are increasingly degraded downstream. Elemental nitrogen, amino acids, and basic amino acids are all preferentially associated with fine minerals. Observed geographical patterns included more positive delta (13)C values in particulate organic matter from high altitude sites and an increase in the abundance and degradation of ultrafiltered dissolved organic matter down the drainage system. Many of these compositional patterns are imprinted within materials carried by low-order, high-altitude tributaries and appear to reflect processes occurring on the landscape. | |||||
BibTeX:
@article{hedges_organic_2000, author = {Hedges, J. I. and Mayorga, E. and Tsamakis, E. and McClain, M. E. and Aufdenkampe, A. and Quay, P. and Richey, J. E. and Benner, R. and Opsahl, S. and Black, B. and Pimentel, T. and Quintanilla, J. and Maurice, L.}, title = {Organic matter in Bolivian tributaries of the Amazon River: A comparison to the lower mainstream}, journal = {Limnology and Oceanography}, year = {2000}, volume = {45}, number = {7}, pages = {1449--1466}, url = {://WOS:000165267100001} } |
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Heald, C.L., Kroll, J.H., Jimenez, J.L., Docherty, K.S., DeCarlo, P.F., Aiken, A.C., Chen, Q., Martin, S.T., Farmer, D.K. and Artaxo, P. | A simplified description of the evolution of organic aerosol composition in the atmosphere | 2010 | Geophysical Research Letters Vol. 37 |
article | DOI URL |
Abstract: Organic aerosol (OA) in the atmosphere consists of a multitude of organic species which are either directly emitted or the products of a variety of chemical reactions. This complexity challenges our ability to explicitly characterize the chemical composition of these particles. We find that the bulk composition of OA from a variety of environments (laboratory and field) occupies a narrow range in the space of a Van Krevelen diagram (H: C versus O:C), characterized by a slope of similar to-1. The data show that atmospheric aging, involving processes such as volatilization, oxidation, mixing of air masses or condensation of further products, is consistent with movement along this line, producing a more oxidized aerosol. This finding has implications for our understanding of the evolution of atmospheric OA and representation of these processes in models. Citation: Heald, C. L., J. H. Kroll, J. L. Jimenez, K. S. Docherty, P. F. DeCarlo, A. C. Aiken, Q. Chen, S. T. Martin, D. K. Farmer, and P. Artaxo (2010), A simplified description of the evolution of organic aerosol composition in the atmosphere, Geophys. Res. Lett., 37, L08803, doi: 10.1029/2010GL042737. | |||||
BibTeX:
@article{heald_simplified_2010, author = {Heald, C. L. and Kroll, J. H. and Jimenez, J. L. and Docherty, K. S. and DeCarlo, P. F. and Aiken, A. C. and Chen, Q. and Martin, S. T. and Farmer, D. K. and Artaxo, P.}, title = {A simplified description of the evolution of organic aerosol composition in the atmosphere}, journal = {Geophysical Research Letters}, year = {2010}, volume = {37}, url = {://WOS:000277033000004}, doi = {https://doi.org/10.1029/2010gl042737} } |
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Hayhoe, S.J., Neill, C., Porder, S., McHorney, R., Lefebvre, P., Coe, M.T., Elsenbeer, H. and Krusche, A.V. | Conversion to soy on the Amazonian agricultural frontier increases streamflow without affecting stormflow dynamics | 2011 | Global Change Biology Vol. 17(5), pp. 1821-1833 |
article | DOI URL |
Abstract: Large-scale soy agriculture in the southern Brazilian Amazon now rivals deforestation for pasture as the region's predominant form of land use change. Such landscape-level change can have substantial consequences for local and regional hydrology, but these effects remain relatively unstudied in this ecologically and economically important region. We examined how the conversion to soy agriculture influences water balances and stormflows using stream discharge (water yields) and the timing of discharge (stream hydrographs) in small (2.5-13.5 km2) forested and soy headwater watersheds in the Upper Xingu Watershed in the state of Mato Grosso, Brazil. We monitored water yield for 1 year in three forested and four soy watersheds. Mean daily water yields were approximately four times higher in soy than forested watersheds, and soy watersheds showed greater seasonal variability in discharge. The contribution of stormflows to annual streamflow in all streams was low (textless 13% of annual streamflow), and the contribution of stormflow to streamflow did not differ between land uses. If the increases in water yield observed in this study are typical, landscape-scale conversion to soy substantially alters water-balance, potentially altering the regional hydrology over large areas of the southern Amazon. | |||||
BibTeX:
@article{hayhoe_conversion_2011, author = {Hayhoe, Shelby J. and Neill, Christopher and Porder, Stephen and McHorney, Richard and Lefebvre, Paul and Coe, Michael T. and Elsenbeer, Helmut and Krusche, Alex V.}, title = {Conversion to soy on the Amazonian agricultural frontier increases streamflow without affecting stormflow dynamics}, journal = {Global Change Biology}, year = {2011}, volume = {17}, number = {5}, pages = {1821--1833}, url = {://WOS:000289117100008}, doi = {https://doi.org/10.1111/j.1365-2486.2011.02392.x} } |
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Hasler, N. and Avissar, R. | What controls evapotranspiration in the amazon basin? | 2007 | Journal of Hydrometeorology Vol. 8(3), pp. 380-395 |
article | DOI URL |
Abstract: Global climate models (GCMs) and regional climate models (RCMs) generally show a decrease in the dry season evapotranspiration (ET) rate over the entire Amazon basin. Based on anecdotal observations, it has been suggested that they probably overestimate tropical rain forest water stress. In this study, eddy covariance flux measurements from eight different towers of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) were used to provide a first look at the spatial variability and temporal cycle of ET throughout the basin. Results show strong seasonality in ET for stations near the equator (2 degrees-3 degrees S), with ET increasing during the dry season (June-September) and decreasing during the wet season (December-March), both correlated (0.75 to 0.94) and in phase with the net radiation annual cycle. In stations located farther south (9 degrees-11 degrees S) no clear seasonality could be identified in either net radiation or ET. For these more southerly stations, net radiation and ET are still correlated (0.76-0.92) in the wet season, but correlations decrease in the dry season (0-0.71), which is likely associated with water stress. For both pasture sites, located in southern Amazonia, ET decreases during the second half of the dry season, indicating progressively increased water stress. GCMs and RCMs indeed tend to overestimate dry season water stress in the Amazon basin and, therefore, should be revised to better simulate this region, which has a key role in the global hydrometeorology. | |||||
BibTeX:
@article{hasler_what_2007, author = {Hasler, Natalia and Avissar, Roni}, title = {What controls evapotranspiration in the amazon basin?}, journal = {Journal of Hydrometeorology}, year = {2007}, volume = {8}, number = {3}, pages = {380--395}, url = {://WOS:000247619500007}, doi = {https://doi.org/10.1175/jhm587.1} } |
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Harte, J., Saleska, S. and Shih, T. | Shifts in plant dominance control carbon-cycle responses to experimental warming and widespread drought | 2006 | Environmental Research Letters Vol. 1(1) |
article | DOI URL |
Abstract: Global climate change is predicted to increase the intensity and frequency of future drought, which in turn may be expected to induce a range of biogeochemical climate feedbacks. A combination of model simulations and observational studies of a recent wide-scale drought, suggested that the drought induced substantial terrestrial ecosystem carbon loss, but hypothesized mechanisms could not be evaluated via comparison to a control. Here, we investigated carbon-cycle responses to climate changes by combining results from a controlled 15-year ecosystem warming experiment in montane grassland with observational data from before and during the recent drought. We found that both experimental warming and real-world drought induced substantial soil carbon loss in our study system, and that the same mechanism, a drying-induced shift in plant species composition and an associated decline in community productivity, provides a common explanation for these declines in soil carbon. | |||||
BibTeX:
@article{harte_shifts_2006, author = {Harte, John and Saleska, Scott and Shih, Tiffany}, title = {Shifts in plant dominance control carbon-cycle responses to experimental warming and widespread drought}, journal = {Environmental Research Letters}, year = {2006}, volume = {1}, number = {1}, url = {://WOS:000202975700004}, doi = {https://doi.org/10.1088/1748-9326/1/1/014001} } |
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Harris, P.P., Huntingford, C., Gash, J.H.C., Hodnett, M.G., Cox, P.M., Malhi, Y. and Araujo, A.C. | Calibration of a land-surface model using data from primary forest sites in Amazonia | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 27-45 |
article | DOI URL |
Abstract: A land-surface model (MOSES) was tested against observed fluxes of heat, water vapour and carbon dioxide for two primary forest sites near Manaus, Brazil. Flux data from one site (called C14) were used to calibrate the model, and data from the other site (called K34) were used to validate the calibrated model. Long-term fluxes of water vapour at C14 and K34 simulated by the uncalibrated model were good, whereas modelled net ecosystem exchange (NEE) was poor. The uncalibrated model persistently underpredicted canopy conductance (g(c)) from mid-morning to mid-afternoon due to saturation of the response to solar radiation at low light levels. This in turn caused a poor simulation of the diurnal cycles of water vapour and carbon fluxes. Calibration of the stomatal conductance/photosynthesis sub-model of MOSES improved the simulated diurnal cycle of g(c) and increased the diurnal maximum NEE, but at the expense of degrading long-term water vapour fluxes. Seasonality in observed canopy conductance due to soil moisture change was not captured by the model. Introducing realistic depth-dependent soil parameters decreased the amount of moisture available for transpiration at each depth and led to the model experiencing soil moisture limitation on canopy conductance during the dry season. However, this limitation had only a limited effect on the seasonality in modelled NEE. | |||||
BibTeX:
@article{harris_calibration_2004, author = {Harris, P. P. and Huntingford, C. and Gash, J. H. C. and Hodnett, M. G. and Cox, P. M. and Malhi, Y. and Araujo, A. C.}, title = {Calibration of a land-surface model using data from primary forest sites in Amazonia}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {27--45}, url = {://WOS:000222024700004 http://www.springerlink.com/content/1ur0xf3ge4e1fdj2/fulltext.pdf}, doi = {https://doi.org/10.1007/s00704-004-0042-y} } |
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Harris, P.P., Huntingford, C., Cox, P.M., Gash, J.H.C. and Malhi, Y. | Effect of soil moisture on canopy conductance of Amazonian rainforest | 2004 | Agricultural and Forest Meteorology Vol. 122(3-4), pp. 215-227 |
article | DOI URL |
Abstract: Estimates of canopy conductance, g(c), were derived from hourly eddy-covariance measurements of evaporation for a primary forest site near Manaus, Brazil, using an inverted Penman-Monteith equation. These data were used to calibrate Jarvis-type models of canopy conductance including and excluding a soil moisture dependence. A period of low canopy conductance in the observations coincided with low soil moisture and high humidity deficit. The model was able to capture this decrease in diurnal maximum g(c) only when a soil moisture dependence was included. The optimised value of wilting point in the soil moisture function was 465 m(3) m(-3), which was comparable with estimates from soil hydraulic properties. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{harris_effect_2004, author = {Harris, P. P. and Huntingford, C. and Cox, P. M. and Gash, J. H. C. and Malhi, Y.}, title = {Effect of soil moisture on canopy conductance of Amazonian rainforest}, journal = {Agricultural and Forest Meteorology}, year = {2004}, volume = {122}, number = {3-4}, pages = {215--227}, url = {://WOS:000220547300007}, doi = {https://doi.org/10.1016/j.agrformet.2003.09.006} } |
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Harris, P.P., Huntingford, C. and Cox, P.M. | Amazon Basin climate under global warming: the role of the sea surface temperature | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1753-1759 |
article | DOI URL |
Abstract: The Hadley Centre coupled climate-carbon cycle model (HadCM3LC) predicts loss of the Amazon rainforest in response to future anthropogenic greenhouse gas emissions. In this study, the atmospheric component of HadCM3LC is used to assess the role of simulated changes in mid-twenty-first century sea surface temperature (SST) in Amazon Basin climate change. When the full HadCM3LC SST anomalies (SSTAs) are used, the atmosphere model reproduces the Amazon Basin climate change exhibited by HadCM3LC, including much of the reduction in Amazon Basin rainfall. This rainfall change is shown to be the combined effect of SSTAs in both the tropical Atlantic and the Pacific, with roughly equal contributions from each basin. The greatest rainfall reduction occurs from May to October, outside of the mature South American monsoon (SAM) season. This dry season response is the combined effect of a more rapid warming of the tropical North Atlantic relative to the south, and warm SSTAs in the tropical east Pacific. Conversely, a weak enhancement of mature SAM season rainfall in response to Atlantic SST change is suppressed by the atmospheric response to Pacific SST. This net wet season response is sufficient to prevent dry season soil moisture deficits from being recharged through the SAM season, leading to a perennial soil moisture reduction and an associated 30% reduction in annual Amazon Basin net primary productivity (NPP). A further 23% NPP reduction occurs in response to a 3.5 degrees C warmer air temperature associated with a global mean SST warming. | |||||
BibTeX:
@article{harris_amazon_2008, author = {Harris, Phil P. and Huntingford, Chris and Cox, Peter M.}, title = {Amazon Basin climate under global warming: the role of the sea surface temperature}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1753--1759}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500005 http://rstb.royalsocietypublishing.org/content/363/1498/1753.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0037} } |
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Harper, A.B., Denning, A.S., Baker, I.T., Branson, M.D., Prihodko, L. and Randall, D.A. | Role of deep soil moisture in modulating climate in the Amazon rainforest | 2010 | Geophysical Research Letters Vol. 37 |
article | DOI URL |
Abstract: Both local and large-scale processes affect the Amazon hydrologic cycle. We investigate the impact of deep soils on the atmosphere through local feedbacks. The Simple Biosphere model, version 3 (SiB3), is coupled to a single column model. Historically, land surface schemes parameterize soil moisture stress based on shallow soils and incorrectly capture seasonal cycles in the Amazon. Following observations, SiB3 is updated to allow deep roots to access soil moisture at depth. The new ("Unstressed") version of SiB3 has a stronger hydrologic cycle, with increased evapotranspiration and moisture export during the dry season. The boundary layer responds through changes in its depth, relative humidity, and turbulent kinetic energy, and these changes feed back to influence wet season onset and intensity. Differences in atmospheric latent heating could affect circulation in a global model. The results have important consequences for modeling the Amazon hydrologic cycle and climate in global climate models. Citation: Harper, A. B., A. S. Denning, I. T. Baker, M. D. Branson, L. Prihodko, and D. A. Randall ( 2010), Role of deep soil moisture in modulating climate in the Amazon rainforest, Geophys. Res. Lett., 37, L05802, doi:10.1029/2009GL042302. | |||||
BibTeX:
@article{harper_role_2010, author = {Harper, Anna B. and Denning, A. Scott and Baker, Ian T. and Branson, Mark D. and Prihodko, Lara and Randall, David A.}, title = {Role of deep soil moisture in modulating climate in the Amazon rainforest}, journal = {Geophysical Research Letters}, year = {2010}, volume = {37}, url = {://WOS:000275302500004}, doi = {https://doi.org/10.1029/2009gl042302} } |
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Harley, P., Vasconcellos, P., Vierling, L., Pinheiro, C.C.D., Greenberg, J., Guenther, A., Klinger, L., De Almeida, S.S., Neill, D., Baker, T., Phillips, O. and Malhi, Y. | Variation in potential for isoprene emissions among Neotropical forest sites | 2004 | Global Change Biology Vol. 10(5), pp. 630-650 |
article | DOI URL |
Abstract: As part of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), we have developed a bottom-up approach for estimating canopy-scale fluxes of isoprene. Estimating isoprene fluxes for a given forest ecosystem requires knowledge of foliar biomass, segregated by species, and the isoprene emission characteristics of the individual tree species comprising the forest. In this study, approximately 38% of 125 tree species examined at six sites in the Brazilian Amazon emitted isoprene. Given logistical difficulties and extremely high species diversity, it was possible to screen only a small percentage of tree species, and we propose a protocol for estimating the emission capacity of unmeasured taxa using a taxonomic approach, in which we assign to an unmeasured genus a value based on the percentage of genera within its plant family which have been shown to emit isoprene. Combining this information with data obtained from 14 tree censuses at four Neotropical forest sites, we have estimated the percentage of isoprene-emitting biomass at each site. The relative contribution of each genus of tree is estimated as the basal area of all trees of that genus divided by the total basal area of the plot. Using this technique, the percentage of isoprene-emitting biomass varied from 20% to 42% (mean=31%; SD=8%). Responses of isoprene emission to varying light and temperature, measured on a sun-adapted leaf of mango (Mangifera indica L.), suggest that existing algorithms developed for temperate species are adequate for tropical species as well. Incorporating these algorithms, estimates of isoprene-emitting biomass, isoprene emission capacity, and site foliar biomass into a canopy flux model, canopy-scale fluxes of isoprene were predicted and compared with the above-canopy fluxes measured at two sites. Our bottom-up approach overestimates fluxes by about 50%, but variations in measured fluxes between the two sites are largely explained by observed variation in the amount of isoprene-emitting biomass. | |||||
BibTeX:
@article{harley_variation_2004, author = {Harley, P. and Vasconcellos, P. and Vierling, L. and Pinheiro, C. C. D. and Greenberg, J. and Guenther, A. and Klinger, L. and De Almeida, S. S. and Neill, D. and Baker, T. and Phillips, O. and Malhi, Y.}, title = {Variation in potential for isoprene emissions among Neotropical forest sites}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {630--650}, url = {://WOS:000221421600008}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00760.x} } |
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Haren, J.v., Oliveira Jr, R., Camargo, P., Keller, M. and Saleska, S. | Tree Species Effects on Soil Properties and Greenhouse Gas Fluxes in East-central Amazonia: Comparison between Monoculture and Diverse Forest [BibTeX] |
2013 | Biotropica Vol. 45(6), pp. 709-718 |
article | |
BibTeX:
@article{haren_tree_2013, author = {Haren, J. van and Oliveira Jr, R.C. and Camargo, P.B. and Keller, M. and Saleska, S.}, title = {Tree Species Effects on Soil Properties and Greenhouse Gas Fluxes in East-central Amazonia: Comparison between Monoculture and Diverse Forest}, journal = {Biotropica}, year = {2013}, volume = {45}, number = {6}, pages = {709--718} } |
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Hamilton, S.K., Sippel, S.J. and Melack, J.M. | Seasonal inundation patterns in two large savanna floodplains of South America: the Llanos de Moxos (Bolivia) and the Llanos del Orinoco (Venezuela and Colombia) | 2004 | Hydrological Processes Vol. 18(11), pp. 2103-2116 |
article | DOI URL |
Abstract: Inundation patterns in two of the largest savanna floodplains of South America were studied by analysis of the 37-GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer (Nimbus-7 satellite). Flooded area was estimated at monthly intervals for January 1979 through to August 1987 using mixing models that account for the major landscape units with distinctive microwave emission characteristics. Results are presented separately for five subregions in each of the two floodplain regions to show the spatial as well as temporal variability in inundation patterns. The total area inundated during the 9 years varied between 2069 and 78 460 km(2) in the Llanos de Moxos (also spelled as Mojos; median area, 23 383 km(2)) and 1278 and 105 454 km(2) in the Llanos del Orinoco (median, 25 374 km(2)) not including the open-water area of permanent takes and river channels. The correlation between flooded area and river stage was used to extend the inundation records over a 30-year period in the Moxos (1967-97) and a 58-year period (1927-85) in the Orinoco. Interannual variability in inundation is greater in the Moxos than the Orinoco. Comparison of these data, however, with a previously published analysis of the Pantanal wetland shows that inundation patterns in these two floodplain regions are not as variable across years as they are in the Pantanal. Copyright (C) 2004 John Wiley Sons, Ltd. | |||||
BibTeX:
@article{hamilton_seasonal_2004, author = {Hamilton, S. K. and Sippel, S. J. and Melack, J. M.}, title = {Seasonal inundation patterns in two large savanna floodplains of South America: the Llanos de Moxos (Bolivia) and the Llanos del Orinoco (Venezuela and Colombia)}, journal = {Hydrological Processes}, year = {2004}, volume = {18}, number = {11}, pages = {2103--2116}, url = {://WOS:000223271800008}, doi = {https://doi.org/10.1002/hyp.5559} } |
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Hamilton, S.K., Sippel, S.J. and Melack, J.M. | Comparison of inundation patterns among major South American floodplains | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] A comparative view of inundation patterns in the large floodplains of South America was derived by analysis of the 37-GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer (SMMR; Nimbus-7 satellite, 1979-1987). The following floodplains were analyzed: (1) mainstem Amazon River floodplain in Brazil; (2) Llanos de Moxos (Beni and Mamore rivers) in Bolivia; (3) Bananal Island (Araguaia River) in Brazil; (4) Llanos del Orinoco (Apure and Meta rivers) in Venezuela and Colombia; (5) Roraima savannas (Branco and Rupununi rivers) in Brazil and Guyana; and (6) Pantanal wetland (Paraguay River) in Brazil. The maximum areas subject to inundation in each region, which include permanent open waters of river channels and lakes, were as follows (in km 2): mainstem Amazon 97,360, Moxos 92,094, Bananal 58,550, Orinoco 107,530, Roraima 16,530, and Pantanal 130,920. The duration of inundation was correlated with the maximum area inundated. Predictive relationships between flooded area and water levels in the nearby rivers allowed extension of the inundation record over nearly a century for the Amazon and Pantanal and several decades for the other floodplains. Interannual variability in the maximum extent of inundation is greatest in the Pantanal, followed by Roraima and Bananal. Based on these extended records, the long-term mean inundation areas (in km(2) and including rivers and lakes) were as follows: mainstem Amazon 46,920, Moxos 29,460, Bananal 13,110, Orinoco 34,700, Roraima 3,480, and Pantanal 34,880. This information is fundamental for hydrological, biogeochemical, and ecological studies of these floodplain-river systems and will improve estimates of methane and other trace gas emissions to the atmosphere from these vast wetlands. | |||||
BibTeX:
@article{hamilton_comparison_2002, author = {Hamilton, S. K. and Sippel, S. J. and Melack, J. M.}, title = {Comparison of inundation patterns among major South American floodplains}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180336500003}, doi = {https://doi.org/10.1029/2000jd000306} } |
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Halverson, J.B., Rickenbach, T., Roy, B., Pierce, H. and Williams, E. | Environmental characteristics of convective systems during TRMM-LBA | 2002 | Monthly Weather Review Vol. 130(6), pp. 1493-1509 |
article | DOI URL |
Abstract: In this paper, data collected from 51 days of continual upper-atmospheric soundings and the Tropical Ocean Global Atmosphere (TOGA) radar at Anglo-Brazilian Amazonian Climate Observation Study (ABRACOS) Hill during the Tropical Rainfall Measuring Mission component of the Brazilian Large Scale Biosphere-Atmosphere (TRMM-LBA) experiment are used to describe the mean thermodynamic and kinematic airmass properties of wet season convection over Rondonia, Brazil. Distinct multiday easterly and westerly lower-tropospheric wind regimes occurred during the campaign with contrasting airmass characteristics. Westerly wind periods featured modest CAPE (1000 J kg(-1)), moist conditions (textgreater90% RH) extending through 700 mb, and shallow (900 mb) speed shear on the order of 10(-4) s(-1). This combination of characteristics promoted convective systems that featured a relatively large fraction of stratiform rainfall and weak convection nearly devoid of lightning. In contrast, easterly regime convective systems were more strongly electrified and featured larger convective rain rates and reduced stratiform rainfall fraction. These systems formed in an environment with larger CAPE (1500 J kg(-1)), drier lower- and midlevel humidities (textless80% RH), and a wind shear layer that was both stronger (10(-3) s(-1)) and deeper (700 mb). The time series of low- and midlevel averaged humidity exhibited marked variability between westerly and easterly regimes and was characterized by low- frequency (i.e., multiday to weekly) variations. In addition to its importance in stratiform rain formation, the humidity content directly influenced cloud cover and, thus, the degree of thermal instability present during regimes. The synoptic-scale origins of these moisture fluctuations are examined. The results reported herein provide an environmental context for ongoing dual-Doppler analyses and numerical modeling case studies of individual TRMM-LBA convective systems. | |||||
BibTeX:
@article{halverson_environmental_2002, author = {Halverson, J. B. and Rickenbach, T. and Roy, B. and Pierce, H. and Williams, E.}, title = {Environmental characteristics of convective systems during TRMM-LBA}, journal = {Monthly Weather Review}, year = {2002}, volume = {130}, number = {6}, pages = {1493--1509}, url = {://WOS:000175268100004}, doi = {https://doi.org/10.1175/1520-0493(2002)130%3C1493:ecocsd%3E2.0.co;2} } |
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Hagen, S.C., Braswell, B.H., Frolking, S., Salas, W.A. and Xiao, X. | Determination of subpixel fractions of nonforested area in the Amazon using multiresolution satellite sensor data | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: We present the results of an analysis that combines coarse and fine spatial resolution remote sensing data to reconstruct time series of nonforested area in a region of the Brazilian Amazon. We used a 10-year sequence (1989-1998) of Landsat Thematic Mapper data for one scene (similar to30,000 km(2)) in Rondonia, Brazil, to parameterize a regression model that uses subsets of AVHRR GAC reflectance data. This model detected information on interannual changes in nonforested area with a combination of detail and coverage greater than would normally be available using either data set alone. Within this domain we retrieved nonforest cover fraction in a cross-validation test with coefficients of determination (R-2) of 0.32 at 8-km resolution and 0.64 at 48-km resolution. At the 48-km resolution the model captures interannual variability and trends of fractional cover within individual pixels that changed considerably over the 10 years of this analysis. The results for this region suggest that retrospective analyses will benefit from further development of techniques combining AVHRR, TM, and other prior information. | |||||
BibTeX:
@article{hagen_determination_2002, author = {Hagen, S. C. and Braswell, B. H. and Frolking, S. and Salas, W. A. and Xiao, X.}, title = {Determination of subpixel fractions of nonforested area in the Amazon using multiresolution satellite sensor data}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200006}, doi = {https://doi.org/10.1029/2000jd000255} } |
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Hadlich, H.L., Durgante, F.M., dos Santos, J., Higuchi, N., Chambers, J.Q. and Vicentini, A. | Recognizing Amazonian tree species in the field using bark tissues spectra [BibTeX] |
2018 | Forest Ecology and Management Vol. 427, 296-304. |
article | |
BibTeX:
@article{hadlich_recognizing_2018, author = {Hadlich, H. L. and Durgante, F. M. and dos Santos, J. and Higuchi, N. and Chambers, J. Q. and Vicentini, A.}, title = {Recognizing Amazonian tree species in the field using bark tissues spectra}, journal = {Forest Ecology and Management}, year = {2018}, volume = {427, 296-304.} } |
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Hacon, S., Carmo, C., Longo, K., Freitas, S., Mourao, D., Ignotti, E., Mello, R. and Artaxo, P. | Biomass Burning as a Driver of Human Exposure to Particulate Matter in the Amazon Region [BibTeX] |
2009 | Epidemiology Vol. 20(6), pp. S81-S82 |
article | URL |
BibTeX:
@article{hacon_biomass_2009, author = {Hacon, Sandra and Carmo, Cleber and Longo, Karla and Freitas, Saulo and Mourao, Dennys and Ignotti, Eliane and Mello, Rafael and Artaxo, Paulo}, title = {Biomass Burning as a Driver of Human Exposure to Particulate Matter in the Amazon Region}, journal = {Epidemiology}, year = {2009}, volume = {20}, number = {6}, pages = {S81--S82}, url = {://WOS:000270874100213} } |
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Guyot, J.L., Jouanneau, J.M. and Wasson, J.G. | Characterisation of river bed and suspended sediments in the Rio Madeira drainage basin (Bolivian Amazonia) | 1999 | Journal of South American Earth Sciences Vol. 12(4), pp. 401-410 |
article | DOI URL |
Abstract: The grain size distribution of river bed sediments in the Rio Madeira drainage basin shows rapid deposition of the coarser material (textgreater 10 mm) as the river flows out of the Andean range to enter the Amazon plain (Llanos). In the Andes, the suspended sediment grain size varies between 0.02 and 0.10 mm in diameter, while in the Llanos the suspended load is dominated by fine silts, between 7 and 13 mu m in diameter. In the Llanos, neither the bed sediment nor the suspended sediment varied along a 800 km reach. (C) 1999 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{guyot_characterisation_1999, author = {Guyot, J. L. and Jouanneau, J. M. and Wasson, J. G.}, title = {Characterisation of river bed and suspended sediments in the Rio Madeira drainage basin (Bolivian Amazonia)}, journal = {Journal of South American Earth Sciences}, year = {1999}, volume = {12}, number = {4}, pages = {401--410}, url = {://WOS:000084537800005}, doi = {https://doi.org/10.1016/s0895-9811(99)00030-9} } |
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Guyon, P., Maenhaut, W., Blazso, M., Janitsek, S., Gelencser, A., Artaxo, P. and Andreae, M.O. | Study of tropical organic aerosol by thermally assisted alkylation-gas chromatography mass spectrometry (vol 68, pg 351, 2003) [BibTeX] |
2004 | Journal of Analytical and Applied Pyrolysis Vol. 71(2), pp. 1027-1029 |
article | DOI URL |
BibTeX:
@article{guyon_study_2004, author = {Guyon, P. and Maenhaut, W. and Blazso, M. and Janitsek, S. and Gelencser, A. and Artaxo, P. and Andreae, M. O.}, title = {Study of tropical organic aerosol by thermally assisted alkylation-gas chromatography mass spectrometry (vol 68, pg 351, 2003)}, journal = {Journal of Analytical and Applied Pyrolysis}, year = {2004}, volume = {71}, number = {2}, pages = {1027--1029}, url = {://WOS:000221210200043}, doi = {https://doi.org/10.1016/j.jaap.2004.03.004} } |
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Guyon, P., Graham, B., Roberts, G.C., Mayol-Bracero, O.L., Maenhaut, W., Artaxo, P. and Andreae, M.O. | Sources of optically active aerosol particles over the Amazon forest | 2004 | Atmospheric Environment Vol. 38(7), pp. 1039-1051 |
article | DOI URL |
Abstract: Size-fractionated ambient aerosol samples were collected at a pasture site and a primary rainforest site in the Brazilian Amazon Basin during two field campaigns (April-May and September-October 1999), as part of the European contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA-EUSTACH). The samples were analyzed for up to 19 trace elements by particle-induced X-ray emission analysis (PIXE), for equivalent black carbon (BCe) by a light reflectance technique and for mass concentration by gravimetric analysis. Additionally, we made continuous measurements of absorption and light scattering by aerosol particles. The vertical chemical composition gradients at the forest site have been discussed in a companion article (Journal of Geophysical Research-Atmospheres 108 (1318), 4591 (doi:4510.1029/2003JD003465)). In this article, we present the results of a source identification and quantitative apportionment study of the wet and dry season aerosols, including an apportionment of the measured scattering and absorption properties of the total aerosol in terms of the identified aerosol sources. Source apportionments (obtained from absolute principal component analysis) revealed that the wet and dry season aerosols contained the same three main components, but in different (absolute and relative) amounts: the wet season aerosol consisted mainly of a natural biogenic component, whereas pyrogenic aerosols dominated the dry season aerosol mass. The third component identified was soil dust, which was often internally mixed with the biomass-burning aerosol. All three components contributed significantly to light extinction during both seasons. At the pasture site, up to 47% of the light absorption was attributed to biogenic particles during the wet season, and up to 35% at the tower site during the wet-to-dry transition period. The results from the present study suggest that, in addition to pyrogenic particles, biogenic and soil dust aerosols must be taken into account when modeling the physical and optical properties of aerosols in forested regions such the Amazon Basin. (C) 2003 Published by Elsevier Ltd. | |||||
BibTeX:
@article{guyon_sources_2004, author = {Guyon, P. and Graham, B. and Roberts, G. C. and Mayol-Bracero, O. L. and Maenhaut, W. and Artaxo, P. and Andreae, M. O.}, title = {Sources of optically active aerosol particles over the Amazon forest}, journal = {Atmospheric Environment}, year = {2004}, volume = {38}, number = {7}, pages = {1039--1051}, url = {://WOS:000188975000011}, doi = {https://doi.org/10.1016/j.atmosenv.2003.10.051} } |
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Guyon, P., Graham, B., Roberts, G.C., Mayol-Bracero, O.L., Maenhaut, W., Artaxo, P. and Andreae, M.O. | In-canopy gradients, composition, sources, and optical properties of aerosol over the Amazon forest | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D18) |
article | DOI URL |
Abstract: [1] As part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia-European Studies on Trace Gases and Atmospheric Chemistry (LBA-EUSTACH), size-fractionated aerosol samples were collected at a primary rain forest in the Brazilian Amazon during two field campaigns in April - May and September - October 1999. These two periods encompassed parts of the wet and dry seasons, respectively. Daytime-nighttime-segregated sampling was carried out at three different heights ( above, within, and below canopy level) on a 54-m meteorological tower at the forest site in order to better characterize the aerosol sources. The samples were analyzed for up to 19 trace elements by particle-induced X-ray emission analysis and for carbonaceous components by thermal-optical analysis. Equivalent black carbon (BCe) and gravimetric analyses were also performed. The average mass concentrations for particles textless 2 μm diameter were 2.2 and 33.5 μg m(-3) for the wet and the dry seasons, respectively. The elements related to biomass burning and soil dust generally exhibited highest concentrations above the canopy and during daytime, while forest-derived aerosol was more concentrated underneath the canopy and during nighttime. These variations can be largely attributed to daytime convective mixing and the formation of a shallow nocturnal boundary layer, along with the possibility of enhanced nighttime release of biogenic aerosol particles. Mass scattering (α(s)) and mass absorption efficiency (α(a)) data indicate that scattering was dominated by fine aerosol, while fine and coarse aerosol both contributed significantly to absorption during both seasons. The data also suggest that components other than elemental carbon were responsible for a substantial fraction of the absorption. | |||||
BibTeX:
@article{guyon_-canopy_2003, author = {Guyon, P. and Graham, B. and Roberts, G. C. and Mayol-Bracero, O. L. and Maenhaut, W. and Artaxo, P. and Andreae, M. O.}, title = {In-canopy gradients, composition, sources, and optical properties of aerosol over the Amazon forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D18}, url = {://WOS:000185889500002}, doi = {https://doi.org/10.1029/2003jd003465} } |
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Guyon, P., Graham, B., Beck, J., Boucher, O., Gerasopoulos, E., Mayol-Bracero, O.L., Roberts, G.C., Artaxo, P. and Andreae, M.O. | Physical properties and concentration of aerosol particles over the Amazon tropical forest during background and biomass burning conditions | 2003 | Atmospheric Chemistry and Physics Vol. 3, pp. 951-967 |
article | URL |
Abstract: We investigated the size distribution, scattering and absorption properties of Amazonian aerosols and the optical thickness of the aerosol layer under the pristine background conditions typical of the wet season, as well as during the biomass-burning-influenced dry season. The measurements were made during two campaigns in 1999 as part of the European contribution to the Large-Scale BiosphereAtmosphere Experiment in Amazonia (LBA-EUSTACH). In moving from the wet to the dry season, median particle numbers were observed to increase from values comparable to those of the remote marine boundary layer (similar to400 cm(-3)) to values more commonly associated with urban smog (similar to4000 cm(-3)), due to a massive injection of submicron smoke particles. Aerosol optical depths at 500 nm increased from 0.05 to 0.8 on average, reaching a value of 2 during the dry season. Scattering and absorption coefficients, measured at 550 nm, showed a concomitant increase from average values of 6.8 and 0.4 Mm(-1) to values of 91 and 10 Mm(-1), respectively, corresponding to an estimated decrease in single-scattering albedo from ca. 0.97 to 0.91. The roughly tenfold increase in many of the measured parameters attests to the dramatic effect that extensive seasonal biomass burning (deforestation, pasture cleaning) is having on the composition and properties of aerosols over Amazonia. The potential exists for these changes to impact on regional and global climate through changes to the extinction of solar radiation as well as the alteration of cloud properties. | |||||
BibTeX:
@article{guyon_physical_2003, author = {Guyon, P. and Graham, B. and Beck, J. and Boucher, O. and Gerasopoulos, E. and Mayol-Bracero, O. L. and Roberts, G. C. and Artaxo, P. and Andreae, M. O.}, title = {Physical properties and concentration of aerosol particles over the Amazon tropical forest during background and biomass burning conditions}, journal = {Atmospheric Chemistry and Physics}, year = {2003}, volume = {3}, pages = {951--967}, url = {://WOS:000184098200001} } |
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Guyon, P., Frank, G.P., Welling, M., Chand, D., Artaxo, P., Rizzo, L., Nishioka, G., Kolle, O., Dias, M., Gatti, L.V., Cordova, A.M. and Andreae, M.O. | Airborne measurements of trace gas and aerosol particle emissions from biomass burning in Amazonia | 2005 | Atmospheric Chemistry and Physics Vol. 5, pp. 2989-3002 |
article | URL |
Abstract: As part of the LBA-SMOCC (Large-Scale Biosphere-Atmosphere Experiment in Amazonia-Smoke, Aerosols, Clouds, Rainfall, and Climate) 2002 campaign, we studied the emission of carbon monoxide (CO), carbon dioxide (CO(2)), and aerosol particles from Amazonian deforestation fires using an instrumented aircraft. Emission ratios for aerosol number (CN) relative to CO (ER(CN/CO)) fell in the range 14-32 cm(-3) ppb(-1) in most of the investigated smoke plumes. Particle number emission ratios have to our knowledge not been previously measured in tropical deforestation fires, but our results are in agreement with values usually found from tropical savanna fires. The number of particles emitted per amount biomass burned was found to be dependent on the fire conditions (combustion efficiency). Variability in ER(CN/CO) between fires was similar to the variability caused by variations in combustion behavior within each individual fire. This was confirmed by observations of CO-to-CO(2) emission ratios (ER(CO/CO2)), which stretched across the same wide range of values for individual fires as for all the fires observed during the sampling campaign, reflecting the fact that flaming and smoldering phases are present simultaneously in deforestation fires. Emission factors (EF) for CO and aerosol particles were computed and a correction was applied for the residual smoldering combustion (RSC) fraction of emissions that are not sampled by the aircraft, which increased the EF by a factor of 1.5-2.1. Vertical transport of smoke from the boundary layer (BL) to the cloud detrainment layer (CDL) and the free troposphere (FT) was found to be a very common phenomenon. We observed a 20% loss in particle number as a result of this vertical transport and subsequent cloud processing, attributable to in-cloud coagulation. This small loss fraction suggests that this mode of transport is very efficient in terms of particle numbers and occurs mostly via non-precipitating clouds. The detrained aerosol particles released in the CDL and FT were larger than in the unprocessed smoke, mostly due to coagulation and secondary growth, and therefore more efficient at scattering radiation and nucleating cloud droplets. This process may have significant atmospheric implications on a regional and larger scale. | |||||
BibTeX:
@article{guyon_airborne_2005, author = {Guyon, P. and Frank, G. P. and Welling, M. and Chand, D. and Artaxo, P. and Rizzo, L. and Nishioka, G. and Kolle, O. and Dias, Mafs and Gatti, L. V. and Cordova, A. M. and Andreae, M. O.}, title = {Airborne measurements of trace gas and aerosol particle emissions from biomass burning in Amazonia}, journal = {Atmospheric Chemistry and Physics}, year = {2005}, volume = {5}, pages = {2989--3002}, url = {://WOS:000233123200001} } |
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Guyon, P., Boucher, O., Graham, B., Beck, J., Mayol-Bracero, O.L., Roberts, G.C., Maenhaut, W., Artaxo, P. and Andreae, M.O. | Refractive index of aerosol particles over the Amazon tropical forest during LBA-EUSTACH 1999 | 2003 | Journal of Aerosol Science Vol. 34(7), pp. 883-907 |
article | DOI URL |
Abstract: Optical properties of aerosol particles were characterized during two field campaigns at a remote rainforest site in Rond (o) over cap nia, Brazil, as part of the project European Studies on Trace Gases and Atmospheric Chemistry, a contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA-EUSTACH). The measurements included background (wet season), biomass burning (dry season), and transition period conditions. Optical measurements of light scattering and absorption were combined with data on number/size distributions in a new iterative method, which retrieves the effective imaginary refractive index of the particles at a wavelength of 545 nm. For ambient relative humidities lower than 80%, background aerosols exhibited an average refractive index of 1.42 - 0.006i. Biomass burning aerosols displayed a much larger imaginary part, with an average refractive index of 1.41 - 0.013i. Other climate-relevant parameters were estimated from Mie calculations. These include single-scattering albedos of 0.93 +/- 0.03 and 0.90 +/- 0.03 (at ambient humidity), asymmetry parameters of 0.63 +/- 0.02 and 0.70 +/- 0.03, and backscatter ratios of 0.12 +/- 0.01 and 0.08 +/- 0.01 for background and biomass burning aerosols, respectively. (C) 2003 Published by Elsevier Ltd. | |||||
BibTeX:
@article{guyon_refractive_2003, author = {Guyon, P. and Boucher, O. and Graham, B. and Beck, J. and Mayol-Bracero, O. L. and Roberts, G. C. and Maenhaut, W. and Artaxo, P. and Andreae, M. O.}, title = {Refractive index of aerosol particles over the Amazon tropical forest during LBA-EUSTACH 1999}, journal = {Journal of Aerosol Science}, year = {2003}, volume = {34}, number = {7}, pages = {883--907}, url = {://WOS:000184302200005}, doi = {https://doi.org/10.1016/s0021-8502(03)00052-1} } |
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Gut, A., van Dijk, S.M., Scheibe, M., Rummel, U., Welling, M., Ammann, C., Meixner, F.X., Kirkman, G.A., Andreae, M.O. and Lehmann, B.E. | NO emission from an Amazonian rain forest soil: Continuous measurements of NO flux and soil concentration | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: The net nitric oxide (NO) flux from the soil of a tropical rain forest site in Reserva Biologica Jaru (Rondonia, Brazil) was continuously measured in May and during September-November 1999 using dynamic chambers. The median net NO flux was 4.7 ng N m(-2) s(-1) in May (1000 individual measurements) and 4.0 ng N m(-2) s(-1) in September-November (4200 individual measurements). The daily variation of the net NO flux was positively correlated to the daily variations of soil temperature. Minor rain events (textless10 mm) had no significant influence on the 24-hour mean net NO flux. Following larger amounts of rain, a 40% reduction of the 24-hour mean net NO flux up to a 150% increase was observed. During the September-November experiment the soil NO concentration and the soil NO bulk diffusion coefficient were measured to calculate the net NO flux using an indirect method. The soil NO concentration was continuously measured at 0.03-m depth. It ranged from 20 to 460 ppb and was positively correlated with soil moisture and soil temperature. The soil bulk diffusion coefficient determined from Rn-222 flux and soil-air activity gradient measurements ranged from 2.7 x 10(-7) to 9.1 x 10(-7) m(-2) s(-1\) and was parameterized with soil air-filled pore space. The median net NO flux calculated by the indirect method was 3.9 ng N m(-2) s(-1) (1600 individual measurements). | |||||
BibTeX:
@article{gut_no_2002, author = {Gut, A. and van Dijk, S. M. and Scheibe, M. and Rummel, U. and Welling, M. and Ammann, C. and Meixner, F. X. and Kirkman, G. A. and Andreae, M. O. and Lehmann, B. E.}, title = {NO emission from an Amazonian rain forest soil: Continuous measurements of NO flux and soil concentration}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200014}, doi = {https://doi.org/10.1029/2001jd000521} } |
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Gut, A., Scheibe, M., Rottenberger, S., Rummel, U., Welling, M., Ammann, C., Kirkman, G.A., Kuhn, U., Meixner, F.X., Kesselmeier, J., Lehmann, B.E., Schmidt, W., Muller, E. and Piedade, M.T.F. | Exchange fluxes of NO2 and O-3 at soil and leaf surfaces in an Amazonian rain forest | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Trace gas exchange of NO2 and O-3 at the soil surface of the primary rain forest in Reserva Biologica Jaru (Rondonia, Brazil) was investigated by chamber and gradient methods. The ground resistance to NO2 and O-3 deposition to soil was quantified for dry and wet surface conditions using dynamic chambers and was found to be fairly constant at 340 +/- 110 and 190 +/- 70 s m(-1), respectively. For clear-sky conditions, the thermal stratification of the air in the first meter from the forest floor was stable during daytime and unstable during nighttime. The aerodynamic resistance to NO2 and O-3 deposition to the ground in the first meter above the forest floor was determined by measurements of Rn-220 and CO2 concentration gradients and CO2 surface fluxes. The aerodynamic resistance of the 1(-m) layer above the ground was 1700 s m(-1) during daytime and 600 s m(-1) during nighttime. The deposition flux of O-3 and NO2 was quantified for clear-sky conditions from the measured concentrations and the quantified resistances. For both trace gases, deposition to the soil was generally observed. The O-3 deposition flux to the soil was only significantly different from zero during daytime. The maximum of -1.2 nmol m(-2) s(-1) was observed at about 1800 and the mean daytime flux was -0.5 nmol m(-2) s(-1). The mean NO2 deposition flux during daytime was -1.6 ng N m(-2) s(-1) and during nighttime -2.2 ng N m(-2) s(-1). The NOx budget at the soil surface yielded net emission day and night. The NO2 deposition flux was 74% of the soil NO emission flux during nighttime and 34% during daytime. The plant uptake of NO2 and O-3 by the leaves of Laetia corymbulosa and Pouteria glomerata, two typical plant species for the Amazon rain forest, was investigated in a greenhouse in Oldenburg (Germany) using branch cuvettes. The uptake of O-3 was found to be completely under stomatal control. The uptake of NO2 was also controlled by the stomatal resistance but an additional mesophyll resistance of the same order of magnitude as the stomatal resistance was necessary to explain the observed uptake rate. | |||||
BibTeX:
@article{gut_exchange_2002, author = {Gut, A. and Scheibe, M. and Rottenberger, S. and Rummel, U. and Welling, M. and Ammann, C. and Kirkman, G. A. and Kuhn, U. and Meixner, F. X. and Kesselmeier, J. and Lehmann, B. E. and Schmidt, W. and Muller, E. and Piedade, M. T. F.}, title = {Exchange fluxes of NO2 and O-3 at soil and leaf surfaces in an Amazonian rain forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200017}, doi = {https://doi.org/10.1029/2001jd000654} } |
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Gunthe, S.S., King, S.M., Rose, D., Chen, Q., Roldin, P., Farmer, D.K., Jimenez, J.L., Artaxo, P., Andreae, M.O., Martin, S.T. and Poschl, U. | Cloud condensation nuclei in pristine tropical rainforest air of Amazonia: size-resolved measurements and modeling of atmospheric aerosol composition and CCN activity | 2009 | Atmospheric Chemistry and Physics Vol. 9(19), pp. 7551-7575 |
article | URL |
Abstract: Atmospheric aerosol particles serving as cloud condensation nuclei (CCN) are key elements of the hydrological cycle and climate. We have measured and characterized CCN at water vapor supersaturations in the range of S=0.10-0.82% in pristine tropical rainforest air during the AMAZE-08 campaign in central Amazonia. The effective hygroscopicity parameters describing the influence of chemical composition on the CCN activity of aerosol particles varied in the range of kappa approximate to 0.1-0.4 (0.16+/-0.06 arithmetic mean and standard deviation). The overall median value of kappa approximate to 0.15 was by a factor of two lower than the values typically observed for continental aerosols in other regions of the world. Aitken mode particles were less hygroscopic than accumulation mode particles (kappa approximate to 0.1 at D approximate to 50 nm; kappa approximate to 0.2 at D approximate to 200 nm), which is in agreement with earlier hygroscopicity tandem differential mobility analyzer (H-TDMA) studies. The CCN measurement results are consistent with aerosol mass spectrometry (AMS) data, showing that the organic mass fraction (f(org)) was on average as high as similar to 90% in the Aitken mode (D textless= 100 nm) and decreased with increasing particle diameter in the accumulation mode (similar to 80% at D approximate to 200 nm). The kappa values exhibited a negative linear correlation with f(org) (R(2)=0.81), and extrapolation yielded the following effective hygroscopicity parameters for organic and inorganic particle components: kappa(org)approximate to 0.1 which can be regarded as the effective hygroscopicity of biogenic secondary organic aerosol (SOA) and kappa(inorg)approximate to 0.6 which is characteristic for ammonium sulfate and related salts. Both the size dependence and the temporal variability of effective particle hygroscopicity could be parameterized as a function of AMS-based organic and inorganic mass fractions (kappa(p)=kappa(org) x f(org)+kappa(inorg) x f(inorg)). The CCN number concentrations predicted with kappa(p) were in fair agreement with the measurement results (similar to 20% average deviation). The median CCN number concentrations at S=0.1-0.82% ranged from N(CCN,0.10)approximate to 35 cm(-3) to N(CCN,0.82)approximate to 160 cm(-3), the median concentration of aerosol particles larger than 30 nm was N(CN,30)approximate to 200 cm(-3), and the corresponding integral CCN efficiencies were in the range of N(CCN,0.10/NCN,30)approximate to 0.1 to N(CCN,0.82/NCN,30)approximate to 0.8. Although the number concentrations and hygroscopicity parameters were much lower in pristine rainforest air, the integral CCN efficiencies observed were similar to those in highly polluted megacity air. Moreover, model calculations of N(CCN,S) assuming an approximate global average value of kappa approximate to 0.3 for continental aerosols led to systematic overpredictions, but the average deviations exceeded similar to 50% only at low water vapor supersaturation (0.1%) and low particle number concentrations (textless= 100 cm(-3)). Model calculations assuming aconstant aerosol size distribution led to higher average deviations at all investigated levels of supersaturation: similar to 60% for the campaign average distribution and similar to 1600% for a generic remote continental size distribution. These findings confirm earlier studies suggesting that aerosol particle number and size are the major predictors for the variability of the CCN concentration in continental boundary layer air, followed by particle composition and hygroscopicity as relatively minor modulators. Depending on the required and applicable level of detail, the information and parameterizations presented in this paper should enable efficient description of the CCN properties of pristine tropical rainforest aerosols of Amazonia in detailed process models as well as in large-scale atmospheric and climate models. |
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BibTeX:
@article{gunthe_cloud_2009, author = {Gunthe, S. S. and King, S. M. and Rose, D. and Chen, Q. and Roldin, P. and Farmer, D. K. and Jimenez, J. L. and Artaxo, P. and Andreae, M. O. and Martin, S. T. and Poschl, U.}, title = {Cloud condensation nuclei in pristine tropical rainforest air of Amazonia: size-resolved measurements and modeling of atmospheric aerosol composition and CCN activity}, journal = {Atmospheric Chemistry and Physics}, year = {2009}, volume = {9}, number = {19}, pages = {7551--7575}, url = {://000270779700020} } |
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Guimaraes, J.R.D., Roulet, M., Lucotte, M. and Mergler, D. | Mercury methylation along a lake-forest transect in the Tapajos river floodplain, Brazilian Amazon: seasonal and vertical variations | 2000 | Science of the Total Environment Vol. 261(1-3), pp. 91-98 |
article | DOI URL |
Abstract: The seasonal and spatial variations of net methylmercury production in sediments, soils and other sites were evaluated by assays with (203)Hg at different depths and locations along a lake-forest transect at lake Enseada Grande, Tapajos river. Soil and sediment samples were taken at the surface and at different depths up to 9 cm. Fresh samples and acidified controls (1-3 g dry wt.) were slurried with local water and incubated in the dark at 25-28 degrees C for 3 days with 0.5-1.6 mu g Hg g(-1) (dry wt.) added as (203)HgCl(2). CH(3) (203)Hg was extracted and measured in scintillation cocktail after acid leaching. Methylmercury production varied by orders of magnitude among sites and among sediment or soil layers. Seasonal variations were smaller than those with sample depth and location. In both seasons, MeHg formation in sediment and soil or flooded soil decreased with depth and was, in the top layers, one order of magnitude higher in the C-rich littoral macrophyte zone (2.3-8.9%) and flooded forest (3.2-4.5%) than in the center of the lake (0.2-0.56%). Similar MeHg production was found in slurried dry soils (dry season) and in soils already flooded for months. In the macrophyte zone soil (dry season), methylation was mainly associated with the thin Paspalum sp. rootlet layer. In the forest site, vertical variation in methylation was less pronounced in flooded than in dry soils and during the inundation the higher methylation rate was found in the flocculent sediment settled over the litter layer. The roots of floating Paspalum sp. were an important Hg methylation site, particularly those heavily colonized with periphyton (3.4-5.4%). Methylation in surface or near-bottom water was undetectable (textless 3 x 10(-2)%) at all sites. Flooded forests and macrophyte mats are specific features of the Amazon and are important links between Hg inputs from natural and manmade sources and MeHg exposure of local populations through fish intake. (C) 2000 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{guimaraes_mercury_2000, author = {Guimaraes, J. R. D. and Roulet, M. and Lucotte, M. and Mergler, D.}, title = {Mercury methylation along a lake-forest transect in the Tapajos river floodplain, Brazilian Amazon: seasonal and vertical variations}, journal = {Science of the Total Environment}, year = {2000}, volume = {261}, number = {1-3}, pages = {91--98}, note = {Edition: 2000/10/19}, url = {://WOS:000089587200009}, doi = {https://doi.org/10.1016/s0048-9697(00)00627-6} } |
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Guild, L.S., Kauffman, J.B., Cohen, W.B., Hlavka, C.A. and Ward, D.E. | Modeling biomass burning emissions for amazon forest and pastures in Rondonia, Brazil | 2004 | Ecological Applications Vol. 14(4), pp. S232-S246 |
article | URL |
Abstract: As a source of atmospheric carbon, biomass burning emissions associated with deforestation in the Amazon are globally significant. Once deforested, these lands continue to be sources of substantial burning emissions for many years due to frequent pasture burning. The objective of this research was to quantify biomass-burning emissions at a local scale. We estimated carbon emissions from three sources: fires associated with primary forest slash, regenerating forest slash, and pastures.-The study was conducted on a 94370-ha section of land surrounding Jamari, Rondonia, Brazil. In the emissions computation, we integrated site-specific, ground-based data (biomass, emission factors for flaming and smoldering combustion, and combustion factors for land-cover types) with a Landsat TM land cover change map of the study area for 1984-1992. This map was used to ascertain changes in land cover based on TM image dates during a period of early colonization and rapid deforestation in Rondonia. Emissions of CO, CO2, CH4, and other hydrocarbon trace gases were calculated. Between 1984 and 1992, we found CO, emissions generated by primary forest slash burning were 694379 Mg C (920 kg C(.)ha(-1.)yr(-1)) and regenerating forest slash burning contributed 23436 Mg C (31 kg C(.)ha(-1.)yr(-1)), whereas cumulative pasture burning produced 238 180 Mg C (316 kg C(.)ha(-1.)yr(-1)). CO and CH4 followed the same trends by land cover type. Primary forest slash burns contributed 73% of the total C emissions whereas burning regenerating forest slash and pasture. produced 2% and 25%, respectively. The major finding of this work is the identification of pasture burning as a potentially important source of pyrogenic emissions, but better data on biomass and combustion efficiency could confirm this finding. Further we demonstrated a novel method for estimating area burned that links land cover type and change to burn frequency. | |||||
BibTeX:
@article{guild_modeling_2004, author = {Guild, L. S. and Kauffman, J. B. and Cohen, W. B. and Hlavka, C. A. and Ward, D. E.}, title = {Modeling biomass burning emissions for amazon forest and pastures in Rondonia, Brazil}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S232--S246}, url = {://WOS:000223269000020} } |
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Guild, L.S., Cohen, W.B. and Kauffman, J.B. | Detection of deforestation and land conversion in Rondonia, Brazil using change detection techniques | 2004 | International Journal of Remote Sensing Vol. 25(4), pp. 731-750 |
article | DOI URL |
Abstract: Fires associated with tropical deforestation, land conversion and land use greatly contribute to emissions as well as the depletion of carbon and nutrient pools. The objective of this research was to compare change detection techniques for identifying deforestation and cattle pasture formation during a period of early colonization and agricultural expansion in the vicinity of Jamari, Rondonia. Multi-date Landsat Thematic Mapper (TM) data between 1984 and 1992 were examined in a 94370 ha area of active deforestation to map land cover change. The tasselled cap (TC) transformation was used to enhance the contrast between forest, cleared areas and regrowth. TC images were stacked into a composite multi-date TC and used in a principal components (PC) transformation to identify change components. In addition, consecutive TC image pairs were differenced and stacked into a composite multi-date differenced image. A maximum likelihood classification of each image composite was compared for identification of land cover change. The multi-date TC composite classification had the best accuracy of 0.78 (kappa). By 1984, only 5% of the study area had been cleared, but by 1992, 11% of the area had been deforested, primarily for pasture, and 7% lost due to hydroelectric dam flooding. Finally, discrimination of pasture versus cultivation was improved due to the ability to detect land under sustained clearing opposed to land exhibiting regrowth with infrequent clearing. | |||||
BibTeX:
@article{guild_detection_2004, author = {Guild, L. S. and Cohen, W. B. and Kauffman, J. B.}, title = {Detection of deforestation and land conversion in Rondonia, Brazil using change detection techniques}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {4}, pages = {731--750}, url = {://WOS:000187844400005}, doi = {https://doi.org/10.1080/01431160310001598935} } |
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Guerreiro, Q., Ruivo, M.L.P., Castro, R., Amarante, C., Rodrigues, H. and Ferreira, O. | Variação sazonal dos atributos químicos de Latossolos em uma área submetida ao estresse hídrico na Amazônia [BibTeX] |
2017 | Boletim Museu Paraense Emílio Goeldi Ciencias Naturais Vol. 11(3), pp. 329-342 |
article | |
BibTeX:
@article{guerreiro_variacao_2017, author = {Guerreiro, Q.L.M. and Ruivo, M. L. P. and Castro, R.M.S. and Amarante, C.B. and Rodrigues, H. and Ferreira, O.O.}, title = {Variação sazonal dos atributos químicos de Latossolos em uma área submetida ao estresse hídrico na Amazônia}, journal = {Boletim Museu Paraense Emílio Goeldi Ciencias Naturais}, year = {2017}, volume = {11}, number = {3}, pages = {329--342} } |
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Guenther, A. | The contribution of reactive carbon emissions from vegetation to the carbon balance of terrestrial ecosystems | 2002 | Chemosphere Vol. 49(8), pp. 837-844 |
article | DOI URL |
Abstract: About 2.4 Pg (1 Pg = 10(15) g) of carbon is emitted annually into the atmosphere as reactive compounds and most of it is eventually oxidized to CO2. Isoprene, a-pinene, methanol, carbon monoxide and other compounds emitted by terrestrial vegetation contribute about half of the total flux and are estimated to produce about 1 Pg C as CO2 per year. The global average for vegetated surfaces is about 7 g C m(-2) per year but could exceed 100 gm(-2) per year at some tropical locations. The magnitude of these fluxes on both the landscape and global scales are small relative to the total carbon emission or deposition but are significant relative to the net fluxes. Reactive carbon fluxes are very sensitive to landcover and climate change and may vary significantly due to future perturbations. This paper summarizes what is known about reactive carbon emissions from vegetation including the magnitude of local, landscape, and global scale fluxes and their contribution to atmospheric CO2. Reasons for including this term in carbon flux models are presented as well as the potential importance on various spatial scales. Past, present and future reactive carbon emissions are expected to differ significantly and the implications of this are discussed. (C) 2002 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{guenther_contribution_2002, author = {Guenther, A.}, title = {The contribution of reactive carbon emissions from vegetation to the carbon balance of terrestrial ecosystems}, journal = {Chemosphere}, year = {2002}, volume = {49}, number = {8}, pages = {837--844}, note = {Edition: 2002/11/15}, url = {://WOS:000178805000006}, doi = {https://doi.org/10.1016/s0045-6535(02)00384-3} } |
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Guan, K., Pan, M., Li, H., Wolf, A., Wu, J., Medvigy, D., Caylor, K., Sheffield, J., Wood, E., Malhi, Y. and Liang, M. | Photosynthetic seasonality of global tropical forests constrained by hydroclimate [BibTeX] |
2015 | Nature Geoscience Vol. 8(4), pp. 284-289 |
article | |
BibTeX:
@article{guan_photosynthetic_2015, author = {Guan, K. and Pan, M. and Li, H. and Wolf, A. and Wu, J. and Medvigy, D. and Caylor, K.K. and Sheffield, J. and Wood, E.F. and Malhi, Y. and Liang, M.}, title = {Photosynthetic seasonality of global tropical forests constrained by hydroclimate}, journal = {Nature Geoscience}, year = {2015}, volume = {8}, number = {4}, pages = {284--289} } |
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Gu, L., Falge, E., Boden, T., Baldocchi, D., Black, T., Saleska, S., Suni, T., Verma, S., Vesala, T., Wofsy, S. and Xu, L. | Objective threshold determination for nighttime eddy flux filtering [BibTeX] |
2005 | Agricultural and Forest Meteorology Vol. 128(3-4), pp. 179-197 |
article | |
BibTeX:
@article{gu_objective_2005, author = {Gu, L. and Falge, E.M. and Boden, T. and Baldocchi, D.D. and Black, T.A. and Saleska, S.R. and Suni, T. and Verma, S.B. and Vesala, T. and Wofsy, S.C. and Xu, L.K.}, title = {Objective threshold determination for nighttime eddy flux filtering}, journal = {Agricultural and Forest Meteorology}, year = {2005}, volume = {128}, number = {3-4}, pages = {179--197} } |
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Gu, J.J., Smith, E.A., Cooper, H.J., Grose, A., Liu, G.S., Merritt, J.D., Waterloo, M.J., de Araujo, A.C., Nobre, A.D., Manzi, A.O., Marengo, J., de Oliveira, P.J., von Randow, C., Norman, J. and Dias, P.S. | Modeling carbon sequestration over the large-scale Amazon basin, aided by satellite observations. Part I: Wet- and dry-season surface radiation budget flux and precipitation variability based on GOES retrievals | 2004 | Journal of Applied Meteorology Vol. 43(6), pp. 870-886 |
article | DOI URL |
Abstract: In this first part of a two-part investigation, large-scale Geostationary Operational Environmental Satellite (GOES) analyses over the Amazonia region have been carried out for March and October of 1999 to provide detailed information on surface radiation budget (SRB) and precipitation variability. SRB fluxes and rainfall are the two foremost cloud-modulated control variables that affect land surface processes, and they require specification at space-time resolutions concomitant with the changing cloud field to represent adequately the complex coupling of energy, water, and carbon budgets. These processes ultimately determine the relative variations in carbon sequestration and carbon dioxide release within a forest ecosystem. SRB and precipitation retrieval algorithms using GOES imager measurements are used to retrieve surface downward radiation and surface rain rates at high space - time resolutions for large-scale carbon budget modeling applications in conjunction with the Large-Scale Biosphere - Atmosphere Experiment in Amazonia. To validate the retrieval algorithms, instantaneous estimates of SRB fluxes and rain rates over 8 km 3 8 km areas were compared with 30-min-averaged surface measurements obtained from tower sites located near Ji-Parana and Manaus in the states of Rondonia and Amazonas, respectively. Because of large aerosol concentrations originating from biomass burning during the dry season (i.e., September and October for purposes of this analysis), an aerosol index from the Total Ozone Mapping Spectrometer is used in the solar radiation retrieval algorithm. The validation comparisons indicate that bias errors for incoming total solar, photosynthetically active radiation ( PAR), and infrared flux retrievals are under 4%, 6%, and 3% of the mean values, respectively. Precision errors at the analyzed space time scales are on the order of 20%, 20%, and 5%. The visible and infrared satellite measurements used for precipitation retrieval do not directly detect rainfall processes, and yet they are responsive to the rapidly changing cloud fields, which are directly associated with precipitation life cycles over the Amazon basin. In conducting the validation analysis at high space - time scales, the comparisons indicate systematic bias uncertainties on the order of 25%. These uncertainties are comparable to published values from an independent assessment of bias uncertainties inherent to the current highest-quality satellite retrievals, that is, from the Tropical Rainfall Measuring Mission. Because precipitation is a weak direct control on photosynthesis for the Amazon ecosystem, that is, photosynthesis is dominated by the strong diurnal controls of incoming PAR and ambient air-canopy temperatures, such uncertainties are tolerable. By the same token, precipitation is a strong control on soil thermal properties and carbon respiration through soil moisture, but the latter is a time-integrating variable and thus inhibits introduction of modeling errors caused by random errors in the precipitation forcing. The investigation concludes with analysis of the monthly, daily, and diurnal variations intrinsic to SRB and rainfall processes over the Amazon basin, including explanations of how these variations arise during wet-and dry-season periods. | |||||
BibTeX:
@article{gu_modeling_2004, author = {Gu, J. J. and Smith, E. A. and Cooper, H. J. and Grose, A. and Liu, G. S. and Merritt, J. D. and Waterloo, M. J. and de Araujo, A. C. and Nobre, A. D. and Manzi, A. O. and Marengo, J. and de Oliveira, P. J. and von Randow, C. and Norman, J. and Dias, P. S.}, title = {Modeling carbon sequestration over the large-scale Amazon basin, aided by satellite observations. Part I: Wet- and dry-season surface radiation budget flux and precipitation variability based on GOES retrievals}, journal = {Journal of Applied Meteorology}, year = {2004}, volume = {43}, number = {6}, pages = {870--886}, url = {://WOS:000222458700004}, doi = {https://doi.org/10.1175/1520-0450(2004)043%3C0870:mcsotl%3E2.0.co;2} } |
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Gu, D., Guenther, A.B., Shilling, J.E., Yu, H., Huang, M., Zhao, C. and Qing Yang Paulo Artaxo, S.K.R.S.T.S.K.M.L.J.T.R.A.F.d.S.O.V.Y.L.M.S.E.G.A.F.C.S.G.L.Z.H.S.T.M. | Airborne observations reveal elevational gradientin tropical forest isoprene emissions [BibTeX] |
2017 | Nature Communications Vol. 8, pp. 15541 |
article | DOI |
BibTeX:
@article{gu_airborne_2017, author = {Gu, Dasa and Guenther, Alex B. and Shilling, John E. and Yu, Haofei and Huang, Maoyi and Zhao, Chun and Qing Yang, Paulo Artaxo, Saewung Kim, Roger Seco, Trissevgeni Stavrakou, Karla M. Longo, Julio Tota, Rodrigo Augusto Ferreira de Souza, Oscar Vega, Ying Liu, Manish Shrivastava, Eliane G. Alves, Fernando C. Santos, Guoyong Leng, Zhiyuan Hu, Scot T. Martin}, title = {Airborne observations reveal elevational gradientin tropical forest isoprene emissions}, journal = {Nature Communications}, year = {2017}, volume = {8}, pages = {15541}, doi = {https://doi.org/10.1038/ncomms15541} } |
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Grossman, D. | Amazon rainforest to get a growth check [BibTeX] |
2016 | Science Vol. 352, pp. 635-636 |
article | |
BibTeX:
@article{grossman_amazon_2016, author = {Grossman, D.}, title = {Amazon rainforest to get a growth check}, journal = {Science}, year = {2016}, volume = {352}, pages = {635--636} } |
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Groenendijk, M., Dolman, A.J., van der Molen, M.K., Leuning, R., Arneth, A., Delpierre, N., Gash, J.H.C., Lindroth, A., Richardson, A.D., Verbeeck, H. and Wohlfahrt, G. | Assessing parameter variability in a photosynthesis model within and between plant functional types using global Fluxnet eddy covariance data | 2011 | Agricultural and Forest Meteorology Vol. 151(1), pp. 22-38 |
article | DOI URL |
Abstract: The vegetation component in climate models has advanced since the late 1960s from a uniform prescription of surface parameters to plant functional types (PFTs) PFTs are used in global land-surface models to provide parameter values for every model grid cell With a simple photosynthesis model we derive parameters for all site years within the Fluxnet eddy covariance data set We compare the model parameters within and between PFTs and statistically group the sites Fluxnet data is used to validate the photosynthesis model parameter variation within a PFT classification Our major result is that model parameters appear more variable than assumed in PFTs Simulated fluxes are of higher quality when model parameters of individual sites or site years are used A simplification with less variation in model parameters results in poorer simulations This indicates that a PFT classification Introduces uncertainty in the variation of the photosynthesis and transpiration fluxes Statistically derived groups of sites with comparable model parameters do not share common vegetation types or climates A simple PFT classification does not reflect the real photosynthesis and transpiration variation Although site year parameters give the best predictions the parameters are generally too specific to be used in a global study The site year parameters can be further used to explore the possibilities of alternative classification schemes (C) 2010 Elsevier B V All rights reserved | |||||
BibTeX:
@article{groenendijk_assessing_2011, author = {Groenendijk, M. and Dolman, A. J. and van der Molen, M. K. and Leuning, R. and Arneth, A. and Delpierre, N. and Gash, J. H. C. and Lindroth, A. and Richardson, A. D. and Verbeeck, H. and Wohlfahrt, G.}, title = {Assessing parameter variability in a photosynthesis model within and between plant functional types using global Fluxnet eddy covariance data}, journal = {Agricultural and Forest Meteorology}, year = {2011}, volume = {151}, number = {1}, pages = {22--38}, url = {://WOS:000285325400003}, doi = {https://doi.org/10.1016/j.agrformet.2010.08.013} } |
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Greenberg, J.P., Guenther, A.B., Petron, G., Wiedinmyer, C., Vega, O., Gatti, L.V., Tota, J. and Fisch, G. | Biogenic VOC emissions from forested Amazonian landscapes | 2004 | Global Change Biology Vol. 10(5), pp. 651-662 |
article | DOI URL |
Abstract: A tethered balloon-sampling platform was used to study biogenic volatile organic compounds (BVOCs) in the atmospheric boundary layer in three distinct moist tropical forest ecoregions, as well as an extensive pasture area, in Amazonia. Approximately 24-40 soundings, including as many as four VOC samples collected simultaneously at various altitudes, were made at each site. Concentrations in the mixed layer increased during morning hours and were relatively constant midday through afternoon. Since most important meteorological and chemical parameters were very similar among the sites during the measurement periods, a BVOC canopy emission model was used with a model of the chemistry of the boundary layer to reproduce the atmospheric concentrations observed. The simulations indicated significantly different midday landscape isoprene and alpha-pinene emission rates for the three forest ecoregions (2200, 5300, 9800 mug m(-2) h(-1) isoprene and 90, 120, and 180 mug m(-2) h(-1)alpha-pinene for the three moist forest ecoregions studied, respectively). The differences in emissions among the ecoregions may be attributed to the species composition, which were markedly different and in which the percentage of isoprene and terpene emitting species also differed significantly. | |||||
BibTeX:
@article{greenberg_biogenic_2004, author = {Greenberg, J. P. and Guenther, A. B. and Petron, G. and Wiedinmyer, C. and Vega, O. and Gatti, L. V. and Tota, J. and Fisch, G.}, title = {Biogenic VOC emissions from forested Amazonian landscapes}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {651--662}, url = {://WOS:000221421600009 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2004.00758.x/asset/j.1365-2486.2004.00758.x.pdf?v=1&t=h6hwo1mf&s=1aa213208c4ef491bd6a12fd42dc5a7f875e1338}, doi = {https://doi.org/10.1111/j.1365-2486.2004.00758.x} } |
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Grant, R.F., Hutyra, L.R., de Oliveira, R.C., Munger, J.W., Saleska, S.R. and Wofsy, S.C. | Modeling the carbon balance of Amazonian rain forests: resolving ecological controls on net ecosystem productivity | 2009 | Ecological Monographs Vol. 79(3), pp. 445-463 |
article | DOI URL |
Abstract: There is still much uncertainty about ecological controls on the rate and direction of net CO(2) exchange by tropical rain forests, in spite of their importance to global C cycling. These controls are thought to arise from hydrologic and nutrient constraints to CO(2) fixation caused by seasonality of precipitation and adverse chemical properties of some major tropical soil types. Using the ecosystem model ecosys, we show that water uptake to a depth of 8 m avoids constraints to CO(2) and energy exchange from soil drying during five-month dry seasons typical for eastern Amazonian forests. This avoidance in the model was tested with eddy covariance (EC) measurements of CO(2) and energy fluxes during 2003 and 2004 over an old-growth forest on an acidic, nutrient-poor oxisol in the Tapajo's National Forest (TNF) in Para, Brazil. Modeled CO(2) fixation was strongly constrained by slow phosphorus (P) uptake caused by low soil pH. Daytime CO(2) influxes in the model were in close agreement with EC measurements (R(2) textgreater 0.8) during both wet and dry seasons. Both modeled and measured fluxes indicated that seasonality of precipitation affected CO(2) and energy exchange more through its effect on radiation and air temperature than on soil water content. When aggregated to a yearly scale, modeled and gap-filled EC CO(2) fluxes indicated that old-growth forest stands in the TNF remained within 100 g C.m(-2).yr(-1) of C neutrality in the absence of major disturbance. Annual C transformations in ecosys were further corroborated by extensive biometric measurements taken in the TNF and elsewhere in the Amazon basin, which also indicated that old-growth forests were either small C sources or small C sinks. Long-term model runs suggested that rain forests could be substantial C sinks for several decades while regenerating after stand-replacing disturbances, but would gradually decline toward C neutrality thereafter. The time course of net ecosystem productivity (NEP) in the model depended upon annual rates of herbivory and tree mortality, which were based on site observations as affected by weather (e. g., El Nino Southern Oscillation [ENSO] events). This dependence suggests that rain forest NEP is strongly controlled by disturbance as well as by weather. | |||||
BibTeX:
@article{grant_modeling_2009, author = {Grant, R. F. and Hutyra, L. R. and de Oliveira, R. C. and Munger, J. W. and Saleska, S. R. and Wofsy, S. C.}, title = {Modeling the carbon balance of Amazonian rain forests: resolving ecological controls on net ecosystem productivity}, journal = {Ecological Monographs}, year = {2009}, volume = {79}, number = {3}, pages = {445--463}, url = {://WOS:000268011200005}, doi = {https://doi.org/10.1890/08-0074.1} } |
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Graham, B., Mayol-Bracero, O.L., Guyon, P., Roberts, G.C., Decesari, S., Facchini, M.C., Artaxo, P., Maenhaut, W., Koll, P. and Andreae, M.O. | Water-soluble organic compounds in biomass burning aerosols over Amazonia - 1. Characterization by NMR and GC-MS | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] As part of the European contribution to the Large-Scale Atmosphere-Biosphere Experiment in Amazonia (LBA-EUSTACH), aerosols were sampled at representative pasture and primary rainforest sites in Rondonia, Brazil, during the 1999 "burning season" and dry-to-wet season transition (September-October). Water-soluble organic compounds (WSOCs) within the samples were characterized using a combination of H-1 Nuclear Magnetic Resonance (NMR) spectroscopy for chemical functional group analysis, and Gas Chromatography-Mass Spectrometry (GC-MS) for identification and quantification of individual low-molecular-weight compounds. The H-1 NMR analysis indicates that WSOCs are predominantly aliphatic or oxygenated aliphatic compounds (alcohols, carboxylic acids, etc.), with a minor content of aromatic rings carrying carboxylic and phenolic groups. Levoglucosan (1,6-anhydro-beta-D-glucose), a well-known cellulose combustion product, was the most abundant individual compound identified by GC-MS (0.04-6.90 mug m(-3)), accounting for 1-6% of the total carbon (TC) and 2-8% of the water-soluble organic carbon (WSOC). Other anhydrosugars, produced by hemicellulose breakdown, were detected in much smaller amounts, in addition to series of acids, hydroxyacids, oxoacids, and polyalcohols (altogether 2-5% of TC, 3-6% of WSOC). Most correlated well with organic carbon, black carbon, and potassium, indicating biomass burning to be the major source. A series of sugar alcohols (mannitol, arabitol, erythritol) and sugars (glucose, fructose, mannose, galactose, sucrose, trehalose) were identified as part of the natural background aerosol and are probably derived from airborne microbes and other biogenic material. The bulk of the WSOCs (86-91% WSOC) eluded analysis by GC-MS and may be predominantly high-molecular weight in nature. | |||||
BibTeX:
@article{graham_water-soluble_2002, author = {Graham, B. and Mayol-Bracero, O. L. and Guyon, P. and Roberts, G. C. and Decesari, S. and Facchini, M. C. and Artaxo, P. and Maenhaut, W. and Koll, P. and Andreae, M. O.}, title = {Water-soluble organic compounds in biomass burning aerosols over Amazonia - 1. Characterization by NMR and GC-MS}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200004}, doi = {https://doi.org/10.1029/2001jd000336} } |
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Graham, B., Guyon, P., Taylor, P.E., Artaxo, P., Maenhaut, W., Glovsky, M.M., Flagan, R.C. and Andreae, M.O. | Organic compounds present in the natural Amazonian aerosol: Characterization by gas chromatography-mass spectrometry | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D24) |
article | DOI URL |
Abstract: As part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)-Cooperative LBA Airborne Regional Experiment (CLAIRE) 2001 campaign in July 2001, separate day and nighttime aerosol samples were collected at a ground-based site in Amazonia, Brazil, in order to examine the composition and temporal variability of the natural "background'' aerosol. We used a high-volume sampler to separate the aerosol into fine (aerodynamic diameter, AD textless 2.5 μm) and coarse (AD textgreater 2.5 mum) size fractions and quantified a range of organic compounds in methanolic extracts of the samples by a gas chromatographic-mass spectrometric technique. The carbon fraction of the compounds could account for an average of 7% of the organic carbon (OC) in both the fine and coarse aerosol fractions. We observed the highest concentrations of sugars, sugar alcohols, and fatty acids in the coarse aerosol samples, which suggests that these compounds are associated with primary biological aerosol particles (PBAP) observed in the forest atmosphere. Of these, trehalose, mannitol, arabitol, and the fatty acids were found to be more prevalent at night, coinciding with a nocturnal increase in PBAP in the 2-10 mum size range (predominantly yeasts and other small fungal spores). In contrast, glucose, fructose, and sucrose showed persistently higher daytime concentrations, coinciding with a daytime increase in large fungal spores, fern spores, pollen grains, and, to a lesser extent, plant fragments (generally textgreater 20 mm in diameter), probably driven by lowered relative humidity and enhanced wind speeds/convective activity during the day. For the fine aerosol samples a series of dicarboxylic and hydroxyacids were detected with persistently higher daytime concentrations, suggesting that photochemical production of a secondary organic aerosol from biogenic volatile organic compounds may have made a significant contribution to the fine aerosol. Anhydrosugars ( levoglucosan, mannosan, galactosan), which are specific tracers for biomass burning, were detected only at low levels in the fine aerosol samples. On the basis of the levoglucosan-to-OC emission ratio measured for biomass burning aerosol, we estimate that an average of similar to16% of the OC in the fine aerosol was due to biomass burning during CLAIRE 2001, indicating that the major fraction was associated with biogenic particles. | |||||
BibTeX:
@article{graham_organic_2003, author = {Graham, B. and Guyon, P. and Taylor, P. E. and Artaxo, P. and Maenhaut, W. and Glovsky, M. M. and Flagan, R. C. and Andreae, M. O.}, title = {Organic compounds present in the natural Amazonian aerosol: Characterization by gas chromatography-mass spectrometry}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D24}, url = {://WOS:000187858400007}, doi = {https://doi.org/10.1029/2003jd003990} } |
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Graham, B., Guyon, P., Maenhaut, W., Taylor, P.E., Ebert, M., Matthias-Maser, S., Mayol-Bracero, O.L., Godoi, R.H.M., Artaxo, P., Meixner, F.X., Moura, M.A.L., Rocha, C., Van Grieken, R., Glovsky, M.M., Flagan, R.C. and Andreae, M.O. | Composition and diurnal variability of the natural Amazonian aerosol | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D24) |
article | DOI URL |
Abstract: As part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)-Cooperative LBA Airborne Regional Experiment (CLAIRE) 2001 campaign, separate day and nighttime aerosol samples were collected in July 2001 at a ground-based site in Amazonia, Brazil, in order to examine the composition and temporal variability of the natural "background'' aerosol. A combination of analytical techniques was used to characterize the elemental and ionic composition of the aerosol. Major particle types larger than similar to0.5 mm were identified by electron and light microscopy. Both the coarse and fine aerosol were found to consist primarily of organic matter (similar to70 and 80% by mass, respectively), with the coarse fraction containing small amounts of soil dust and sea-salt particles and the fine fraction containing some non-sea-salt sulfate. Coarse particulate mass concentrations (CPM approximate to PM10 - PM2) were found to be highest at night (average = 3.9 +/- 1.4 mg m(-3), mean night-to-day ratio = 1.9 +/- 0.4), while fine particulate mass concentrations (FPM approximate to PM2) increased during the daytime (average = 2.6 +/- 0.8 mg m(-3), mean night-to-day ratio = 0.7 +/- 0.1). The nocturnal increase in CPM coincided with an increase in primary biological particles in this size range (predominantly yeasts and other fungal spores), resulting from the trapping of surface-derived forest aerosol under a shallow nocturnal boundary layer and a lake-land breeze effect at the site, although active nocturnal sporulation may have also contributed. Associated with this, we observed elevated nighttime concentrations of biogenic elements and ions (P, S, K, Cu, Zn, NH4+) in the CPM fraction. For the FPM fraction a persistently higher daytime concentration of organic carbon was found, which indicates that photochemical production of secondary organic aerosol from biogenic volatile organic compounds may have made a significant contribution to the fine aerosol. Dust and sea-salt-associated elements/ions in the CPM fraction, and non-sea-salt sulfate in the FPM fraction, showed higher daytime concentrations, most likely due to enhanced convective downward mixing of long-range transported aerosol. | |||||
BibTeX:
@article{graham_composition_2003, author = {Graham, B. and Guyon, P. and Maenhaut, W. and Taylor, P. E. and Ebert, M. and Matthias-Maser, S. and Mayol-Bracero, O. L. and Godoi, R. H. M. and Artaxo, P. and Meixner, F. X. and Moura, M. A. L. and Rocha, Ched and Van Grieken, R. and Glovsky, M. M. and Flagan, R. C. and Andreae, M. O.}, title = {Composition and diurnal variability of the natural Amazonian aerosol}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D24}, url = {://WOS:000187858400009}, doi = {https://doi.org/10.1029/2003jd004049} } |
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Grace, J. and Rayment, M. | Respiration in the balance [BibTeX] |
2000 | Nature Vol. 404(6780), pp. 819-20 |
article | DOI URL |
BibTeX:
@article{grace_respiration_2000, author = {Grace, J. and Rayment, M.}, title = {Respiration in the balance}, journal = {Nature}, year = {2000}, volume = {404}, number = {6780}, pages = {819--20}, note = {Edition: 2000/04/29}, url = {http://www.ncbi.nlm.nih.gov/pubmed/10786772}, doi = {https://doi.org/10.1038/35009170} } |
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Grace, J. and Malhi, Y. | Global change - Carbon dioxide goes with the flow [BibTeX] |
2002 | Nature Vol. 416(6881), pp. 594-595 |
article | DOI URL |
BibTeX:
@article{grace_global_2002, author = {Grace, J. and Malhi, Y.}, title = {Global change - Carbon dioxide goes with the flow}, journal = {Nature}, year = {2002}, volume = {416}, number = {6881}, pages = {594--595}, note = {Edition: 2002/04/12}, url = {://WOS:000174901900025}, doi = {https://doi.org/10.1038/416594b} } |
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Grace, J. | The Amazon Carbon Balance: An Evaluation of Methods and Results [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 79-100 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_amazon_2016, author = {Grace, John}, title = {The Amazon Carbon Balance: An Evaluation of Methods and Results}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {79--100}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Grace, J. | Understanding and managing the global carbon cycle | 2004 | Journal of Ecology Vol. 92(2), pp. 189-202 |
article | DOI URL |
Abstract: 1 Biological carbon sinks develop in mature ecosystems that have high carbon storage when these systems are stimulated to increase productivity, so that carbon gains by photosynthesis run ahead of carbon losses by heterotrophic respiration, and the stocks of carbon therefore increase. This stimulation may occur through elevated CO2 concentration, nitrogen deposition or by changes in climate. 2 Sinks also occur during the 'building' phase of high carbon ecosystems, for example following establishment of forests by planting. 3 New methods have been developed to identify biological carbon sinks: ground based measurements using eddy covariance coupled with inventory methods, atmospheric methods which rely on repeated measurement of carbon dioxide concentrations in a global network, and mathematical models which simulate the processes of production, storage and decomposition of organic matter. There is broad agreement among the results from these methods: carbon sinks are currently found in tropical, temperate and boreal forests as well as the ocean. 4 However, on a global scale the effect of the terrestrial sinks (absorbing 2-3 billion tonnes of carbon per year) is largely offset by deforestation in the tropics (losing 1-2 billion tonnes of carbon per year). 5 The Kyoto Protocol provides incentives for the establishment of sinks. Unfortunately, it does not provide an incentive to protect existing mature ecosystems which constitute both stocks of carbon and (currently) carbon sinks. 6 Incentives would be enhanced, if protection and nature conservation were to be part of any international agreement relating to carbon sinks. | |||||
BibTeX:
@article{grace_understanding_2004, author = {Grace, J.}, title = {Understanding and managing the global carbon cycle}, journal = {Journal of Ecology}, year = {2004}, volume = {92}, number = {2}, pages = {189--202}, url = {://WOS:000220382500001}, doi = {https://doi.org/10.1111/j.0022-0477.2004.00874.x} } |
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Graça, P.M.L.d.A., Santos Junior, M.A.d., Rocha, V.M., Fearnside, P.M., Emilio, T., Menger, J.d.S., Marciente, R., Bobrowiec, P.E.D., Venticinque, E.M., Antunes, A.P., Bastos, A.N. and Rohe, F. | Cenários de desmatamento para região de influência da rodovia BR-319: perda potencial de habitats, status de proteção e ameaça para a biodiversidade [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 91-104 |
incollection | |
BibTeX:
@incollection{emilio_cenarios_2014, author = {Graça, Paulo Maurício Lima de Alencastro and Santos Junior, Marcelo Augusto dos and Rocha, Vinícius Machado and Fearnside, Philip Martin and Emilio, Thaise and Menger, Juliana da Silva and Marciente, Rodrigo and Bobrowiec, Paulo Estefano Dineli and Venticinque, Eduardo Martins and Antunes, André Pinassi and Bastos, Anderson Nakanishi and Rohe, Fabio}, title = {Cenários de desmatamento para região de influência da rodovia BR-319: perda potencial de habitats, status de proteção e ameaça para a biodiversidade}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {91--104}, note = {Section: 8} } |
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Grabowski, W.W., Bechtold, P., Cheng, A., Forbes, R., Halliwell, C., Khairoutdinov, M., Lang, S., Nasuno, T., Petch, J., Tao, W.K., Wong, R., Wu, X. and Xu, K.M. | Daytime convective development over land: A model intercomparison based on LBA observations | 2006 | Quarterly Journal of the Royal Meteorological Society Vol. 132(615), pp. 317-344 |
article | DOI URL |
Abstract: This paper investigates daytime convective development over land and its representation in single-column models (SCMs) and cloud-resolving models (CRMs). A model intercomparison case is developed based on observations of the diurnal cycle and convection during the rainy season in Amazonia. The focus is on the 6 h period between sunrise and early afternoon which was identified in previous studies as critical for the diurnal cycle over summertime continents in numerical weather prediction and climate models. This period is characterized by the formation and growth of a well-mixed convective boundary layer from the early morning temperature and moisture profiles as the surface sensible- and latent-heat fluxes increase after sunrise. It proceeds with the formation of shallow convective clouds as the convective boundary layer deepens, and leads to the eventual transition from shallow to deep precipitating convection around local noon. To provide a benchmark for other models, a custom-designed set of simulations, applying increasing in time computational domain and decreasing spatial resolution, was executed. The SCMs reproduced the previously identified problem with premature development of deep convection, less than two hours after sunrise. The benchmark simulations suggest a possible route to improve SCMs by considering a time-evolving cumulus entrainment rate as convection evolves from shallow to deep and the cloud width increases up to an order of magnitude. The CRMs featuring horizontal and length around 500 m are capable of capturing the qualitative aspects of the benchmark simulations, but there are significant differences among the models. Two-dimensional CRMs tend to simulate too rapid a transition from shallow to deep convection and too high a cloud cover. | |||||
BibTeX:
@article{grabowski_daytime_2006, author = {Grabowski, W. W. and Bechtold, P. and Cheng, A. and Forbes, R. and Halliwell, C. and Khairoutdinov, M. and Lang, S. and Nasuno, T. and Petch, J. and Tao, W. K. and Wong, R. and Wu, X. and Xu, K. M.}, title = {Daytime convective development over land: A model intercomparison based on LBA observations}, journal = {Quarterly Journal of the Royal Meteorological Society}, year = {2006}, volume = {132}, number = {615}, pages = {317--344}, url = {://WOS:000236697900004}, doi = {https://doi.org/10.1256/qj.04.147} } |
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Gouveia, D.A., Barja, B., Barbosa, H.M.J., Seifert, P., Baars, H., Pauliquevis, T. and Artaxo, P. | Optical and geometrical properties of cirrus clouds in Amazonia derived from 1 year of ground-based lidar measurements [BibTeX] |
2017 | Atmos. Chem. Phys. Vol. 17(5), pp. 3619-3636 |
article | DOI URL |
BibTeX:
@article{gouveia_optical_2017, author = {Gouveia, D. A. and Barja, B. and Barbosa, H. M. J. and Seifert, P. and Baars, H. and Pauliquevis, T. and Artaxo, P.}, title = {Optical and geometrical properties of cirrus clouds in Amazonia derived from 1 year of ground-based lidar measurements}, journal = {Atmos. Chem. Phys.}, year = {2017}, volume = {17}, number = {5}, pages = {3619--3636}, url = {https://acp.copernicus.org/articles/17/3619/2017/}, doi = {https://doi.org/10.5194/acp-17-3619-2017} } |
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Gouveia, D.A., Barbosa, H.M.J. and Barja, B. | Characterization of cirrus clouds in central Amazon (2.89ºS, 59.97ºW): Firsts results from observations in 2011 [BibTeX] |
2014 | Óptica Pura e Aplicada Vol. 47, pp. 109-114 |
article | |
BibTeX:
@article{gouveia_characterization_2014, author = {Gouveia, D. A. and Barbosa, H. M. J. and Barja, B.}, title = {Characterization of cirrus clouds in central Amazon (2.89ºS, 59.97ºW): Firsts results from observations in 2011}, journal = {Óptica Pura e Aplicada}, year = {2014}, volume = {47}, pages = {109--114} } |
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Goulden, M.L., Miller, S.D., da Rocha, H.R., Menton, M.C., de Freitas, H.C., Figueira, A. and de Sousa, C.A.D. | Diel and seasonal patterns of tropical forest CO2 exchange | 2004 | Ecological Applications Vol. 14(4), pp. S42-S54 |
article | URL |
Abstract: We used, eddy covariance to measure the net exchange of CO2 between the atmosphere and an old-growth tropical forest in Para, Brazil from I July 2000 to 1 July 2001. The mean air temperature and daily temperature range varied little year-round; the rainy season lasted from late December to around July. Daytime CO2 uptake under high irradiance averaged 16-19 mumol(.)m(-2.)s(-1) . Light was the main controller of CO2 exchange, accounting for 48% of the half-hour-to-half-hour variance. The rate of canopy photosynthesis at a given irradiance was lower in the afternoon than the morning. This photosynthetic inhibition was probably caused by high evaporative demand, high temperature, an intrinsic circadian rhythm, or a combination of the three. Wood increment increased from January to May, suggesting greater rates of carbon sequestration during the wet season. However, the daily net CO2 exchange measured by eddy covariance revealed the opposite trend, with greater carbon accumulation during the dry season. A reduction in respiration during the dry season was an important cause of this seasonal pattern. The surface litter was desiccated in the dry season, and the seasonal pattern of respiration appears to be a direct result of reduced forest floor decomposition during drought. In contrast, canopy photosynthesis was not directly reduced by the dry season, probably because deep rooting allows the forest to avoid drought stress | |||||
BibTeX:
@article{goulden_diel_2004, author = {Goulden, M. L. and Miller, S. D. and da Rocha, H. R. and Menton, M. C. and de Freitas, H. C. and Figueira, Ames and de Sousa, C. A. D.}, title = {Diel and seasonal patterns of tropical forest CO2 exchange}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S42--S54}, url = {://WOS:000223269000006} } |
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Goulden, M.L., Miller, S.D. and da Rocha, H.R. | Nocturnal cold air drainage and pooling in a tropical forest | 2006 | Journal of Geophysical Research-Atmospheres Vol. 111(D8) |
article | DOI URL |
Abstract: The usefulness of eddy covariance for understanding terrestrial carbon exchange has been hampered by uncertainty over the magnitude and causes of a systematic underestimation of CO2 efflux on calm nights. We combined in situ measurements of the temperature, wind and CO2 profile with nocturnal Land Surface Temperature (LST) imagery from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) to infer the patterns of cold air drainage in an Amazonian tropical forest. The meteorological tower was located on a flat plateau that sloped gently to the southwest. The vertical profile from 0 to 64 m above ground level was divisible into two air parcels at night: a warm, low CO2, upper parcel and a cool, high CO2, lower parcel that was stable with respect to the upper parcel. The nocturnal wind direction of the upper parcel was from the east, a pattern that is consistent with the general circulation, whereas the wind direction of the lower parcel was from the northeast, a pattern that implies drainage down the local topographic gradient. The nocturnal patterns of LST were closely related to local topography and land use. In general, a nearby river was warm, gullies were cold, plateau centers were cold, stream drainages were cold, pastures were particularly cold, and upper slopes and plateau edges were warm. The in situ temperature and wind observations, combined with the observed relationship between elevation and nocturnal LST and the occurrence of warm thermal belts extending inward from the edges of plateaus, imply that cold air drainage occurs on clear nights. The slope of the relationship between LST and elevation varied between nights, indicating that the degree of thermal stratification, and possibly the extent of cold air drainage, also varied. The night-tonight variation in stratification across the landscape was correlated with the vertical temperature gradient at the tower but not the above-canopy friction velocity (u*). Criteria associated with vertical temperature gradients may prove better than u* for screening nocturnal eddy covariance observations to eliminate periods that underestimate CO2 flux. | |||||
BibTeX:
@article{goulden_nocturnal_2006, author = {Goulden, M. L. and Miller, S. D. and da Rocha, H. R.}, title = {Nocturnal cold air drainage and pooling in a tropical forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2006}, volume = {111}, number = {D8}, url = {://WOS:000237412100001}, doi = {https://doi.org/10.1029/2005jd006037} } |
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Göss-Souza, D., Mendes, L., Borges, C., Baretta, D., Tsai, S. and Rodrigues, J. | Soil microbial community dynamics and assembly under long-term land use change [BibTeX] |
2017 | FEMS Microbiology Ecology Vol. 93(fix109) |
article | |
BibTeX:
@article{goss-souza_soil_2017, author = {Göss-Souza, D. and Mendes, L.W. and Borges, C.D. and Baretta, D. and Tsai, S.M. and Rodrigues, J.L.M.}, title = {Soil microbial community dynamics and assembly under long-term land use change}, journal = {FEMS Microbiology Ecology}, year = {2017}, volume = {93}, number = {fix109} } |
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Gonzales-Araujo, R., Candido, L., Kayano, M., Souza R. A. F., R. and Andreoli | A influência do evento El Niño Oscilação Sul e Atlântico Equatorial na precipitação sobre as regiões norte e nordeste da América do Sul [BibTeX] |
2013 | Acta Amazonica Vol. 43, pp. 469-480 |
article | |
BibTeX:
@article{gonzales-araujo_influencia_2013, author = {Gonzales-Araujo, R. ; Candido, L. ; Kayano, M. ; Souza, R. A. F., R.; Andreoli}, title = {A influência do evento El Niño Oscilação Sul e Atlântico Equatorial na precipitação sobre as regiões norte e nordeste da América do Sul}, journal = {Acta Amazonica}, year = {2013}, volume = {43}, pages = {469--480} } |
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Gonçalves, W.A., Machado, L.A.T. and Kirstetter, P.-E. | Influence of biomass aerosol on precipitation over the Central Amazon: an observational study [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 6789-6800 |
article | |
BibTeX:
@article{goncalves_influence_2015, author = {Gonçalves, W. A. and Machado, L. A. T. and Kirstetter, P.-E.}, title = {Influence of biomass aerosol on precipitation over the Central Amazon: an observational study}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {6789--6800} } |
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Gonçalves, P.H.L., Oliveira, E.C.d., Silva, M.A.V., Neves, L.d.O., Costa, A.C.L.d. and Costa, J.M.N.d. | Influência da temperatura do solo no efluxo de CO2 do solo em uma floresta tropical da Amazônia oriental [BibTeX] |
2009 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 141-144 |
article | |
BibTeX:
@article{goncalves_influencia_2009, author = {Gonçalves, Paulo Henrique L. and Oliveira, Evandro C. de and Silva, Marcos Antonio V. and Neves, Leonardo de O. and Costa, Antônio Carlos L. da and Costa, José Maria N. da}, title = {Influência da temperatura do solo no efluxo de CO2 do solo em uma floresta tropical da Amazônia oriental}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Especial Micrometeorologia}, pages = {141--144} } |
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Gonçalves, N.B., Lopes, A.P., Dalagnol, R., Wu, J., Pinho, D.M. and Nelson, B.W. | Both near-surface and satellite remote sensing confirm drought legacy effect on tropical forest leaf phenology after 2015/2016 ENSO drought | 2020 | Remote Sensing of Environment Vol. 237, pp. 111489 |
article | DOI URL |
Abstract: Amazon forest leaf phenology patterns have often been inferred from the Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI). But reliable MODIS detection of seasonal and interannual leaf phenology patterns has also been questioned and is generally not validated with field observation. Here we compare inter-annual patterns of local-scale upper canopy leaf phenology and demography derived from tower-mounted phenocams at two upland forest sites in the Central Amazon, to corresponding satellite vegetation indices retrieved from MODIS-MAIAC (Multi-Angle Implementation of Atmospheric Correction). We focus on forest response to an unprecedented drought caused by the El Niño of 2015-16. At both sites, multi-year phenocam data showed post-drought shifts in leaf demography. These were consistent with MODIS-MAIAC anomalies in two vegetation indices. Specifically, a precocious leaf flush at both sites during the first two post-drought months, Feb-Mar 2016, caused (1) an anomalous decrease in flushing trees in Jun–Jul of 2016 and (2) an increase of trees with early mature stage leaves (2-4 mo age) in Apr-May-Jun of 2016. At both sites, these two phenological anomalies showed up in MODIS-MAIAC as, respectively, (1) a strong negative anomaly in Gcc (Green chromatic coordinate), which prior work has shown to be sensitive to the abundance of leaves 0-1 mo old, and (2) a strong positive anomaly in EVI, which is sensitive to abundance of leaves 2-4 mo age. A shift to sub-optimal seasonal leaf age mix is expected to change the ecosystem-scale intrinsic photosynthetic capacity for textasciitilde18 month after the drought. | |||||
BibTeX:
@article{goncalves_both_2020, author = {Gonçalves, Nathan Borges and Lopes, Aline Pontes and Dalagnol, Ricardo and Wu, Jin and Pinho, Davieliton Mesquita and Nelson, Bruce Walker}, title = {Both near-surface and satellite remote sensing confirm drought legacy effect on tropical forest leaf phenology after 2015/2016 ENSO drought}, journal = {Remote Sensing of Environment}, year = {2020}, volume = {237}, pages = {111489}, url = {https://www.sciencedirect.com/science/article/pii/S0034425719305085}, doi = {https://doi.org/10.1016/j.rse.2019.111489} } |
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Gonçalves, N.B., Dalagnol, R., Wu, J., Pontes-Lopes, A., Stark, S.C. and Nelson, B.W. | Amazon forest spectral seasonality is consistent across sensor resolutions and driven by leaf demography [BibTeX] |
2023 | ISPRS Journal of Photogrammetry and Remote Sensing Vol. 196, pp. 93-104 |
article | DOI URL |
BibTeX:
@article{goncalves_amazon_2023, author = {Gonçalves, Nathan B. and Dalagnol, Ricardo and Wu, Jin and Pontes-Lopes, Aline and Stark, Scott C. and Nelson, Bruce W.}, title = {Amazon forest spectral seasonality is consistent across sensor resolutions and driven by leaf demography}, journal = {ISPRS Journal of Photogrammetry and Remote Sensing}, year = {2023}, volume = {196}, pages = {93--104}, url = {https://www.sciencedirect.com/science/article/pii/S0924271622003173}, doi = {https://doi.org/10.1016/j.isprsjprs.2022.12.001} } |
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Gonçalves, L.J.M., Coelho, S.M.S.C., Kubota, P.Y. and Souza, D.C. | Interaction between cloud–radiation, atmospheric dynamics and thermodynamics based on observational data from GoAmazon 2014/15 and a cloud-resolving model [BibTeX] |
2022 | Atmos. Chem. Phys. Vol. 22, pp. 15509-15526 |
article | DOI |
BibTeX:
@article{goncalves_interaction_2022, author = {Gonçalves, Layrson J. M. and Coelho, Simone M. S. C. and Kubota, Paulo Y. and Souza, Dayana C.}, title = {Interaction between cloud–radiation, atmospheric dynamics and thermodynamics based on observational data from GoAmazon 2014/15 and a cloud-resolving model}, journal = {Atmos. Chem. Phys.}, year = {2022}, volume = {22}, pages = {15509--15526}, doi = {https://doi.org/10.5194/acp-22-15509-2022} } |
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Gonçalves, L.G.G.d., Shuttleworth, W.J., Nijssen, B., Burke, E.J., Marengo, J.A., Chou, S.C., Houser, P. and Toll, D.L. | Evaluation of model-derived and remotely sensed precipitation products for continental South America | 2006 | Journal of Geophysical Research-Atmospheres Vol. 111(D16) |
article | DOI URL |
Abstract: [ 1] This paper investigates the reliability of some of the more important remotely sensed daily precipitation products available for South America as a precursor to the possible implementation of a South America Land Data Assimilation System. Precipitation data fields calculated as 6 hour predictions by the CPTEC Eta model and three different satellite-derived estimates of precipitation ( Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN), National Environmental Satellite, Data and Information Service (NESDIS), and Tropical Rainfall Measuring Mission (TRMM)) are compared with the available observations of daily total rainfall across South America. To make this comparison, the threat score, fractional-covered area, and relative volumetric bias of the model-calculated and remotely sensed estimates are computed for the year 2000. The results show that the Eta model-calculated data and the NESDIS product capture the area without precipitation within the domain reasonably well, while the TRMM and PERSIANN products tend to underestimate the area without precipitation and to heavily overestimate the area with a small amount of precipitation. In terms of precipitation amount the NESDIS product significantly overestimates and the TRMM product significantly underestimates precipitation, while the Eta model-calculated data and PERSIANN product broadly match the domain average observations. However, both tend to bias the zonal location of precipitation more heavily toward the equator than the observations. In general, the Eta model-calculated data outperform the several remotely sensed data products currently available and evaluated in the present study. | |||||
BibTeX:
@article{goncalves_evaluation_2006, author = {Gonçalves, L. Gustavo Goncalves de and Shuttleworth, W. James and Nijssen, Bart and Burke, Eleanor J. and Marengo, Jose A. and Chou, Sin Chan and Houser, Paul and Toll, David L.}, title = {Evaluation of model-derived and remotely sensed precipitation products for continental South America}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2006}, volume = {111}, number = {D16}, url = {://WOS:000240333300001}, doi = {https://doi.org/10.1029/2005jd006276} } |
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Gonçalves, L.G.d., Shuttleworth, W.J., Burke, E.J., Houser, P., Toll, D.L., Rodell, M. and Arsenault, K. | Toward a South America Land Data Assimilation System: Aspects of land surface model spin-up using the simplified simple biosphere | 2006 | Journal of Geophysical Research-Atmospheres Vol. 111(D17) |
article | DOI URL |
Abstract: [1] This paper describes a spin-up experiment conducted over South America using the Simplified Simple Biosphere (SSiB) land surface model to study the process of model adjustment to atmospheric forcing data. The experiment was carried out as a precursor to the use of SSiB in a South American Land Data Assimilation System (SALDAS). The results from an 11 year long recursive simulation using three different initial conditions of soil wetness ( control, wet and dry) are examined. The control run was initiated by interpolation of the NCEP/DOE Global Reanalysis-2 (NCEP/DOE R- 2) soil moisture data set. In each case the time required for the model to reach equilibrium was calculated. The wet initialization leads to a faster adjustment of the soil moisture field, followed by the control and then the dry initialization. Overall, the final spin-up states using the SSiB-based SALDAS are generally wetter than both the NCEP/DOE R- 2 and the Centro de Previsao do Tempo e Estudos Climaticos (CPTEC - Brazilian Center for Weather Forecast and Climate Studies) operational initial soil moisture states, consequently modeled latent heat is higher and sensible heat lower in the final year of simulation when compared with the first year. Selected regions, i.e., in semiarid northeastern Brazil, the transition zone to the south of the Amazon tropical forest, and the central Andes were studied in more detail because they took longer to spin up ( up to 56 months) when compared with other areas ( less than 24 months). It is shown that there is a rapid change in the soil moisture in all layers in the first 2 months of simulation followed by a subsequent slow and steady adjustment: This could imply there are increasing errors in medium range simulations. Spin-up is longest where frozen soil is present for long periods such as in the central Andes. | |||||
BibTeX:
@article{goncalves_toward_2006, author = {Gonçalves, L.Gustavo Goncalves de and Shuttleworth, William James and Burke, Eleanor J. and Houser, Paul and Toll, David L. and Rodell, Matthew and Arsenault, Kristi}, title = {Toward a South America Land Data Assimilation System: Aspects of land surface model spin-up using the simplified simple biosphere}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2006}, volume = {111}, number = {D17}, url = {://WOS:000240643700001}, doi = {https://doi.org/10.1029/2005jd006297} } |
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Gonçalves, L.G.G.d., Borak, J.S., Costa, M.H., Saleska, S.R., Baker, I., Restrepo-Coupe, N., Muza, M.N., Poulter, B., Verbeeck, H., Fisher, J.B., Arain, M.A., Arkin, P., Cestaro, B.P., Christoffersen, B., Galbraith, D., Guan, X., van den Hurk, B.J., Ichii, K., Imbuzeiro, H.M.A., Jain, A.K. and al. , e. | Overview of the Large-Scale Biosphere–Atmosphere Experiment in Amazonia Data Model Intercomparison Project (LBA-DMIP) [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183(15 December 2013), pp. 111-127 |
article | |
BibTeX:
@article{goncalves_overview_2013, author = {Gonçalves, Luis Gustavo Gonçalves de and Borak, Jordan S. and Costa, Marcos Heil and Saleska, Scott R. and Baker, Ian and Restrepo-Coupe, Natalia and Muza, Michel Nobre and Poulter, Benjamin and Verbeeck, Hans and Fisher, Joshua B. and Arain, M. Altaf and Arkin, Phillip and Cestaro, Bruno P. and Christoffersen, Bradley and Galbraith, David and Guan, Xiaodan and van den Hurk, Bart J.J.M. and Ichii, Kazuhito and Imbuzeiro, Hewlley M. Acioli and Jain, Atul K. and al., et}, title = {Overview of the Large-Scale Biosphere–Atmosphere Experiment in Amazonia Data Model Intercomparison Project (LBA-DMIP)}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, number = {15 December 2013}, pages = {111--127} } |
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Goncalves, L.G.G., Shuttleworth, W.J., Vila, D., Larroza, E., Bottino, M.J., Herdies, D.L., Aravequia, J.A., De Mattos, J.G.Z., Toll, D.L., Rodell, M. and Houser, P. | The South American Land Data Assimilation System (SALDAS) 5-Yr Retrospective Atmospheric Forcing Datasets | 2009 | Journal of Hydrometeorology Vol. 10(4), pp. 999-1010 |
article | DOI URL |
Abstract: The definition and derivation of a 5-yr, 0.125 degrees, 3-hourly atmospheric forcing dataset that is appropriate for use in a Land Data Assimilation System operating across South America is described. Because surface observations are limited in this region, many of the variables were taken from the South American Regional Reanalysis; however, remotely sensed data were merged with surface observations to calculate the precipitation and downward shortwave radiation fields. The quality of this dataset was evaluated against the surface observations available. There are regional differences in the biases for all variables in the dataset, with volumetric biases in precipitation of the order 0-1 mm day(-1) and RMSE of 5-15 mm day(-1), biases in surface solar radiation of the order 10 W m(-2) and RMSE of 20 W m(-2), positive biases in temperature typically between 0 and 4 K depending on the region, and positive biases in specific humidity around 2-3 g kg(-1) in tropical regions and negative biases around 1-2 g kg(-1) farther south. | |||||
BibTeX:
@article{goncalves_south_2009, author = {Goncalves, Luis Gustavo G. and Shuttleworth, William J. and Vila, Daniel and Larroza, Eliane and Bottino, Marcus J. and Herdies, Dirceu L. and Aravequia, Jose A. and De Mattos, Joao G. Z. and Toll, David L. and Rodell, Matthew and Houser, Paul}, title = {The South American Land Data Assimilation System (SALDAS) 5-Yr Retrospective Atmospheric Forcing Datasets}, journal = {Journal of Hydrometeorology}, year = {2009}, volume = {10}, number = {4}, pages = {999--1010}, url = {://WOS:000269262800010}, doi = {https://doi.org/10.1175/2009jhm1049.1} } |
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Goncalves, L.G.G., Burke, E.J., Shuttleworth, W.J., Chan, C.S. and Marengo, J.A. | Application of improved ecosystem aerodynamics in regional weather forecasts | 2004 | Ecological Applications Vol. 14(4), pp. S17-S21 |
article | URL |
Abstract: This paper reports the impact of applying improved representation of the area-average aerodynamic properties of South American ecosystems on 7-d weather forecasts made with the Brazilian regional forecast model (Eta-SSiB). Two pairs of 7-d forecasts were made, each pair starting from the same initial conditions on I January 1999 and on 24 June 1999, respectively. In one run, the aerodynamic properties of the ecosystem used for each modeled grid square were those of the most common vegetation present. In the second, the grid-average aerodynamic properties of the vegetation were calculated using aggregation rules in combination with a high-resolution land-cover data set. There are marked differences in the aerodynamic properties of the underlying ecosystems in these two runs in some regions, notably around the Amazon River basin, in regions where there has been land-cover change, and in portions of southern Brazil. The 7-d average, predicted ecosystem-surface exchanges, near-surface temperature, and precipitation for the two pairs of runs were compared. There were differences between the forecasts that were most noticeable in regions where the ecosystem's aerodynamic properties were most dissimilar, but also elsewhere. Given the limited nature of the experiments reported, these preliminary results should be treated with care. Nonetheless, they suggest the need for more systematic study of the significance of ecosystems on regional weather forecasts in South America. | |||||
BibTeX:
@article{goncalves_application_2004, author = {Goncalves, L. G. G. and Burke, E. J. and Shuttleworth, W. J. and Chan, C. S. and Marengo, J. A.}, title = {Application of improved ecosystem aerodynamics in regional weather forecasts}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S17--S21}, url = {://WOS:000223269000003} } |
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Goncalves, F.L.T., Martins, J.A. and Silva Dias, M.A. | Shape parameter analysis using cloud spectra and gamma functions in the numerical modeling RAMS during LBA Project at Amazonian region, Brazil | 2008 | Atmospheric Research Vol. 89(1-2), pp. 1-11 |
article | DOI URL |
Abstract: The microphysical variable shape parameters have been investigated considering a numerical simulation based on RAMS (Regional Atmospheric Modeling System), with focus on southwest Amazon Basin during the transition from dry to wet seasons within the scope of LBA (The Large Scale Biosphere Atmosphere Experiment in Amazonia). All data were obtained during the dry-to-wet campaign from September to October 2003. Three precipitation events were chosen during the campaign, classified as polluted, intermediary and clean events. The dataset, for the description of the observed convective systems, includes airborne observations with a microphysics airplane. The variables were cloud droplet contents and spectra, in several flights; radiosonde launches; a 10 cut Doppler radar; visible and IR satellite maps and rain gauge network. The preliminary results have shown that over polluted areas, shape parameters with higher values, from 5 to 7 are better fitted to cloud spectra observations, than the usual shape parameter 2 used in RAMS microphysics default table. For its turn, shape parameter 2 is related to the cleaner areas, i.e., without biomass burning. On the other hand, the numerical simulations, reproducing as close as possible the microphysical variable spatial distributions in the observed dataset, have shown that the average total rainfall precipitation at the surface generally decreases as the CCN concentration and shape parameter increases. CCN vertical and temporal profiles support that result, emphasizing that the higher CCN concentrations are related to biomass burning, where higher shape parameters are better fitted. Additionally, it is possible to conclude that different shape parameters and CCN concentrations may influence directly the maximum and average amount of precipitation and cloud water, implying that different regions should have each the proper specification characteristics. Shape parameters and CCN concentrations are quite useful tools in order to evaluate the spatial and temporal cloud patterns as well as, the rainfall amount with regional implications. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{goncalves_shape_2008, author = {Goncalves, F. L. T. and Martins, J. A. and Silva Dias, M. A.}, title = {Shape parameter analysis using cloud spectra and gamma functions in the numerical modeling RAMS during LBA Project at Amazonian region, Brazil}, journal = {Atmospheric Research}, year = {2008}, volume = {89}, number = {1-2}, pages = {1--11}, url = {://WOS:000257520900001}, doi = {https://doi.org/10.1016/j.atmosres.2007.12.005} } |
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Goncalves de Goncalves, L.G., Shuttleworth, W.J., Chou, S.C., Xue, Y., Houser, P.R., Toll, D.L., Marengo, J. and Rodell, M. | Impact of different initial soil moisture fields on Eta model weather forecasts for South America | 2006 | Journal of Geophysical Research-Atmospheres Vol. 111(D17) |
article | DOI URL |
Abstract: [ 1] Two 7-day weather simulations were made for South America in July 2003 and January 2004 ( in the Southern Hemisphere summer and winter) to investigate the impacts of using different soil moisture initialization fields in the Eta model coupled to the Simplified Simple Biosphere (SSiB) land surface model. The alternative initial soil moisture fields were ( 1) the soil moisture climatology used operationally by the Centro de Previsao do Tempo e Estudos Climaticos in Brazil and ( 2) the soil moisture fields generated by a South American Land Data Assimilation System (SALDAS) based on SSiB. When the SALDAS soil moisture fields were used, there was an increase in the model performance relative to climatology in the equitable threat score calculated with respect to observed surface precipitation fields and a decrease ( up to 53%) in the root-mean-square error relative to the NCEP analysis of the modeled geopotential height at 500 hPa and mean sea level pressure. However, there was small change in the model skill in positioning the primary South American weather systems because of a change in the upper troposphere circulation caused by SALDAS initialization, most noticeably in the South Atlantic Convergence Zone. | |||||
BibTeX:
@article{goncalves_de_goncalves_impact_2006, author = {Goncalves de Goncalves, L. Gustavo and Shuttleworth, William James and Chou, Sin Chan and Xue, Yongkang and Houser, Paul R. and Toll, David L. and Marengo, Jose and Rodell, Matthew}, title = {Impact of different initial soil moisture fields on Eta model weather forecasts for South America}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2006}, volume = {111}, number = {D17}, url = {://WOS:000240333800001}, doi = {https://doi.org/10.1029/2005jd006309} } |
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Gomes, J.B., Webler, A.D., Aguiar, R.G., Aguiar, L.J.G. and Nunes, M.L. | Padrão dos Fluxos de Calor Latente e Sensível em uma Área de Pastagem em Rondônia. [BibTeX] |
2018 | Vol. 1(1)Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental, pp. 91-98 |
incollection | |
BibTeX:
@incollection{org_padrao_2018, author = {Gomes, J. B. and Webler, A. D. and Aguiar, R. G. and Aguiar, L. J G. and Nunes, M. L.}, title = {Padrão dos Fluxos de Calor Latente e Sensível em uma Área de Pastagem em Rondônia.}, booktitle = {Estudos Ambientais em Território Amazônico sob a Perspectiva da Engenharia Ambiental}, publisher = {Appris Editora}, year = {2018}, volume = {1}, number = {1}, pages = {91--98} } |
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Gomes, J.B., Webler, A.D., Aguiar, R.G., Aguiar, L.J.G. and Nunes, M.L. | Conversão de florestas tropicais em sistemas pecuários na Amazônia: quais as implicações no microclima da região? [BibTeX] |
2015 | Revista Brasileira de Climatologia Vol. 17, pp. 67-81 |
article | |
BibTeX:
@article{gomes_conversao_2015, author = {Gomes, J. B. and Webler, A. D. and Aguiar, R. G. and Aguiar, L. J G. and Nunes, M. L.}, title = {Conversão de florestas tropicais em sistemas pecuários na Amazônia: quais as implicações no microclima da região?}, journal = {Revista Brasileira de Climatologia}, year = {2015}, volume = {17}, pages = {67--81} } |
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Gomes, H. and Lemes, M. | Revisão de métodos de cálculo da divergência e uma aplicação usando o método cinemático para determinação de movimentos verticais na atmosfera [BibTeX] |
2007 | Revista Brasileira de Meteorologia Vol. 22(1), pp. 112 120 |
article | |
BibTeX:
@article{gomes_revisao_2007, author = {Gomes, H.B. and Lemes, M.A.M.}, title = {Revisão de métodos de cálculo da divergência e uma aplicação usando o método cinemático para determinação de movimentos verticais na atmosfera}, journal = {Revista Brasileira de Meteorologia}, year = {2007}, volume = {22}, number = {1}, pages = {112 120} } |
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Gomes Alves, E., Aquino Santana, R., Quaresma Dias-Júnior, C., Botía, S., Taylor, T., Yáñez-Serrano, A.M., Kesselmeier, J., Lembo Silveira de Assis, P.I., Martins, G., de Souza, R., Duvoisin Júnior, S., Guenther, A., Gu, D., Tsokankunku, A., Sörgel, M., Nelson, B., Pinto, D., Komiya, S., Martins Rosa, D., Weber, B., Barbosa, C., Robin, M., Feeley, K.J., Duque, A., Londoño Lemos, V., Contreras, M.P., Idarraga, A., López A, N., Husby, C. and Jestrow, B. | Intra- and inter-annual changes in isoprene emission from central Amazonia [BibTeX] |
2023 | EGUsphere Vol. 2023, pp. 1-35 |
article | DOI URL |
BibTeX:
@article{gomes_alves_intra-_2023, author = {Gomes Alves, E. and Aquino Santana, R. and Quaresma Dias-Júnior, C. and Botía, S. and Taylor, T. and Yáñez-Serrano, A. M. and Kesselmeier, J. and Lembo Silveira de Assis, P. I. and Martins, G. and de Souza, R. and Duvoisin Júnior, S. and Guenther, A. and Gu, D. and Tsokankunku, A. and Sörgel, M. and Nelson, B. and Pinto, D. and Komiya, S. and Martins Rosa, D. and Weber, B. and Barbosa, C. and Robin, M. and Feeley, K. J. and Duque, A. and Londoño Lemos, V. and Contreras, M. P. and Idarraga, A. and López A, N. and Husby, C. and Jestrow, B.}, title = {Intra- and inter-annual changes in isoprene emission from central Amazonia}, journal = {EGUsphere}, year = {2023}, volume = {2023}, pages = {1--35}, url = {https://egusphere.copernicus.org/preprints/egusphere-2023-168/}, doi = {https://doi.org/10.5194/egusphere-2023-168} } |
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Gomes, A. and Luizão, F. | Leaf and Soil Nutrients in a Chronosequence of Second-Growth Forest in Central Amazonia: Implications for Restoration of Abandoned Lands [BibTeX] |
2011 | Restoration Ecology, pp. DOI: 10.1111/j.1526-100X.2011.00773.x | article | |
BibTeX:
@article{gomes_leaf_2011, author = {Gomes, A.C.S. and Luizão, F.J.}, title = {Leaf and Soil Nutrients in a Chronosequence of Second-Growth Forest in Central Amazonia: Implications for Restoration of Abandoned Lands}, journal = {Restoration Ecology}, year = {2011}, pages = {DOI: 10.1111/j.1526--100X.2011.00773.x} } |
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Gloor, J., Ziv, G., Brienen, R., Schöngart, J., Peylin, P., Ladvocat Cintra, B., Feldpausch, T., Phillips, O., Baker J., M. and Barichivich | Recent Amazon Climate as background for possible ongoing and future changes of Amazon humid forests [BibTeX] |
2015 | Global Biogeochemical Cycles Vol. 29, pp. 1384-1399 |
article | DOI |
BibTeX:
@article{gloor_recent_2015, author = {Gloor, J; Ziv, G; Brienen, R; Schöngart, J; Peylin, P; Ladvocat Cintra, B; Feldpausch, T; Phillips, O; Baker, J., M; Barichivich}, title = {Recent Amazon Climate as background for possible ongoing and future changes of Amazon humid forests}, journal = {Global Biogeochemical Cycles}, year = {2015}, volume = {29}, pages = {1384--1399}, doi = {https://doi.org/10.1002/2014GB005080} } |
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Gloor, M, Galbraith, D, Feldpausch, TR, Schöngart, J, Guyot, JL, Espinoza, JC, Lloyd, J, & Phillips, OL. and Brienen, RJW | Intensification of the Amazon hydrological cycle over the last two decades. [BibTeX] |
2013 | Geophysical Research Letters | article | DOI |
BibTeX:
@article{gloor_m_intensification_2013, author = {Gloor M, Galbraith D, Feldpausch TR, Schöngart J, Guyot JL, Espinoza JC, Lloyd J, & Phillips OL., Brienen RJW}, title = {Intensification of the Amazon hydrological cycle over the last two decades.}, journal = {Geophysical Research Letters}, year = {2013}, doi = {https://doi.org/10.1002/grl.50377} } |
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Gloor, M., Phillips, O.L., Lloyd, J.J., Lewis, S.L., Malhi, Y., Baker, T.R., Lopez-Gonzalez, G., Peacock, J., Almeida, S., Alves de Oliveira, A.C., Alvarez, E., Amaral, I., Arroyo, L., Aymard, G., Banki, O., Blanc, L., Bonal, D., Brando, P., Chao, K.J., Chave, J., Davila, N., Erwin, T., Silva, J., Di Fiore, A., Feldpausch, T.R., Freitas, A., Herrera, R., Higuchi, N., Honorio, E., Jimenez, E., Killeen, T., Laurance, W., Mendoza, C., Monteagudo, A., Andrade, A., Neill, D., Nepstad, D., Nunez Vargas, P., Penuela, M.C., Pena Cruz, A., Prieto, A., Pitman, N., Quesada, C., Salomao, R., Silveira, M., Schwarz, M., Stropp, J., Ramirez, F., Ramirez, H., Rudas, A., ter Steege, H., Silva, N., Torres, A., Terborgh, J., Vasquez, R. and van der Heijden, G. | Does the disturbance hypothesis explain the biomass increase in basin-wide Amazon forest plot data? | 2009 | Global Change Biology Vol. 15(10), pp. 2418-2430 |
article | DOI URL |
Abstract: Positive aboveground biomass trends have been reported from old-growth forests across the Amazon basin and hypothesized to reflect a large-scale response to exterior forcing. The result could, however, be an artefact due to a sampling bias induced by the nature of forest growth dynamics. Here, we characterize statistically the disturbance process in Amazon old-growth forests as recorded in 135 forest plots of the RAINFOR network up to 2006, and other independent research programmes, and explore the consequences of sampling artefacts using a data-based stochastic simulator. Over the observed range of annual aboveground biomass losses, standard statistical tests show that the distribution of biomass losses through mortality follow an exponential or near-identical Weibull probability distribution and not a power law as assumed by others. The simulator was parameterized using both an exponential disturbance probability distribution as well as a mixed exponential-power law distribution to account for potential large-scale blowdown events. In both cases, sampling biases turn out to be too small to explain the gains detected by the extended RAINFOR plot network. This result lends further support to the notion that currently observed biomass gains for intact forests across the Amazon are actually occurring over large scales at the current time, presumably as a response to climate change. | |||||
BibTeX:
@article{gloor_does_2009, author = {Gloor, M. and Phillips, O. L. and Lloyd, J. J. and Lewis, S. L. and Malhi, Y. and Baker, T. R. and Lopez-Gonzalez, G. and Peacock, J. and Almeida, S. and Alves de Oliveira, A. C. and Alvarez, E. and Amaral, I. and Arroyo, L. and Aymard, G. and Banki, O. and Blanc, L. and Bonal, D. and Brando, P. and Chao, K. J. and Chave, J. and Davila, N. and Erwin, T. and Silva, J. and Di Fiore, A. and Feldpausch, T. R. and Freitas, A. and Herrera, R. and Higuchi, N. and Honorio, E. and Jimenez, E. and Killeen, T. and Laurance, W. and Mendoza, C. and Monteagudo, A. and Andrade, A. and Neill, D. and Nepstad, D. and Nunez Vargas, P. and Penuela, M. C. and Pena Cruz, A. and Prieto, A. and Pitman, N. and Quesada, C. and Salomao, R. and Silveira, Marcos and Schwarz, M. and Stropp, J. and Ramirez, F. and Ramirez, H. and Rudas, A. and ter Steege, H. and Silva, N. and Torres, A. and Terborgh, J. and Vasquez, R. and van der Heijden, G.}, title = {Does the disturbance hypothesis explain the biomass increase in basin-wide Amazon forest plot data?}, journal = {Global Change Biology}, year = {2009}, volume = {15}, number = {10}, pages = {2418--2430}, url = {://WOS:000269577800006}, doi = {https://doi.org/10.1111/j.1365-2486.2009.01891.x} } |
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Gloor, E. | Climate and the Amazonian Carbon Balance [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 101-117 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_climate_2016, author = {Gloor, Emanuel}, title = {Climate and the Amazonian Carbon Balance}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {101--117}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Glicker, H.S., Lawler, M.J., Ortega, J., De Sá, S., Martin, S.T., Artaxo, P., Vega Bustillos, O., de Souza, R., Tota, J., Carlton, A. and Smith, J.N. | Chemical composition of ultrafine aerosol particles in central Amazonia during the wet season [BibTeX] |
2019 | Atmospheric Chemistry And Physics Vol. 19, pp. 13053-13066 |
article | DOI |
BibTeX:
@article{glicker_chemical_2019, author = {Glicker, H. S. and Lawler, M. J. and Ortega, J. and De Sá, S.S. and Martin, S. T. and Artaxo, P. and Vega Bustillos, O. and de Souza, R. and Tota, J. and Carlton, A. and Smith, J. N.}, title = {Chemical composition of ultrafine aerosol particles in central Amazonia during the wet season}, journal = {Atmospheric Chemistry And Physics}, year = {2019}, volume = {19}, pages = {13053--13066}, doi = {https://doi.org/10.5194/acp-19-13053-2019} } |
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Githeko, A.K., Lindsay, S.W., Confalonieri, U.E. and Patz, J.A. | Climate change and vector-borne diseases: a regional analysis | 2000 | Bull World Health Organ Vol. 78(9), pp. 1136-47 |
article | URL |
Abstract: Current evidence suggests that inter-annual and inter-decadal climate variability have a direct influence on the epidemiology of vector-borne diseases. This evidence has been assessed at the continental level in order to determine the possible consequences of the expected future climate change. By 2100 it is estimated that average global temperatures will have risen by 1.0-3.5 degrees C, increasing the likelihood of many vector-borne diseases in new areas. The greatest effect of climate change on transmission is likely to be observed at the extremes of the range of temperatures at which transmission occurs. For many diseases these lie in the range 14-18 degrees C at the lower end and about 35-40 degrees C at the upper end. Malaria and dengue fever are among the most important vector-borne diseases in the tropics and subtropics; Lyme disease is the most common vector-borne disease in the USA and Europe. Encephalitis is also becoming a public health concern. Health risks due to climatic changes will differ between countries that have developed health infrastructures and those that do not. Human settlement patterns in the different regions will influence disease trends. While 70% of the population in South America is urbanized, the proportion in sub-Saharan Africa is less than 45%. Climatic anomalies associated with the El Nino-Southern Oscillation phenomenon and resulting in drought and floods are expected to increase in frequency and intensity. They have been linked to outbreaks of malaria in Africa, Asia and South America. Climate change has far-reaching consequences and touches on all life-support systems. It is therefore a factor that should be placed high among those that affect human health and survival. | |||||
BibTeX:
@article{githeko_climate_2000, author = {Githeko, A. K. and Lindsay, S. W. and Confalonieri, U. E. and Patz, J. A.}, title = {Climate change and vector-borne diseases: a regional analysis}, journal = {Bull World Health Organ}, year = {2000}, volume = {78}, number = {9}, pages = {1136--47}, note = {Edition: 2000/10/06}, url = {http://www.ncbi.nlm.nih.gov/pubmed/11019462} } |
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Girardin, Y., Doughty, C.E., Metcalfe, D.B., Meir, P., Del Aguila-Pasquel, J., Araujo-Murakami, A., da Costa, A.C.L., Silva-Espejo, J.E., Farfán Amézquita, F., Rowland Lucy ., C.A.J. and Malhi | Seasonal trends of Amazonian rainforest phenology, net primary productivity, and carbon allocation [BibTeX] |
2016 | Global Biogeochemical Cycles Vol. 30, pp. 700-715 |
article | |
BibTeX:
@article{girardin_seasonal_2016, author = {Girardin, Yadvinder ; Doughty, Christopher E. ; Metcalfe, Daniel B. ; Meir, Patrick ; Del Aguila-Pasquel, Jhon ; Araujo-Murakami, Alejandro ; da Costa, Antonio C. L. ; Silva-Espejo, Javier E. ; Farfán Amézquita, Filio ; Rowland, Lucy ., Cécile A. J. ; Malhi}, title = {Seasonal trends of Amazonian rainforest phenology, net primary productivity, and carbon allocation}, journal = {Global Biogeochemical Cycles}, year = {2016}, volume = {30}, pages = {700--715} } |
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Girardin, E., del Aguila-Pasquel, J., Dahlsjo, C.A.L., Doughty, C.E., Jeffery, K.J., Moore, S., Oliveras, I., Riutta, T., Rowland, L.M., Araujo Murakami, A., Addo-Danso, S.D., Brando, P., Burton, C., Ondo, F.E., Duah-Gyamfi, A., Farfan Amezquita, F., Freitag, R., Hancco Pacha, F., Huasco, W.H., Ibrahim, F., Mbou, A.T., Mihindou, V.M., Peixoto, K.S., Rocha, W., Rossi, L.C., Seixas, M., Silva-Espejo, J.E., Abernethy, K.A., Adu-Bredu, S., Barlow, J., da Costa, A.C.L., Marimon, B.S., Marimon-Junior, B.H., Meir, P., Metcalfe, D.B., Phillips, O.L., White, L.J.T., Malhi Yadvinder., C.A.J. and Berenguer | ENSO Drives interannual variation of forest woody growth across the tropics [BibTeX] |
2018 | Philosophical Transactions of The Royal Society B-Biological Sciences Vol. 373, pp. 20170410 |
article | |
BibTeX:
@article{girardin_enso_2018, author = {Girardin, Erika; del Aguila-Pasquel, Jhon; Dahlsjo, Cecilia A. L.; Doughty, Christopher E.; Jeffery, Kathryn J.; Moore, Sam; Oliveras, Imma; Riutta, Terhi; Rowland, Lucy M.; Araujo Murakami, Alejandro; Addo-Danso, Shalom D.; Brando, Paulo; Burton, Chad; Ondo, Fidele Evouna; Duah-Gyamfi, Akwasi; Farfan Amezquita, Filio; Freitag, Renata; Hancco Pacha, Fernando; Huasco, Walter Huaraca; Ibrahim, Forzia; Mbou, Armel T.; Mihindou, Vianet Mihindou; Peixoto, Karine S.; Rocha, Wanderley; Rossi, Liana C.; Seixas, Marina; Silva-Espejo, Javier E.; Abernethy, Katharine A.; Adu-Bredu, Stephen; Barlow, Jos; da Costa, Antonio C. L.; Marimon, Beatriz S.; Marimon-Junior, Ben H.; Meir, Patrick; Metcalfe, Daniel B.; Phillips, Oliver L.; White, Lee J. T.; Malhi, Yadvinder., Cecile A. J.; Berenguer}, title = {ENSO Drives interannual variation of forest woody growth across the tropics}, journal = {Philosophical Transactions of The Royal Society B-Biological Sciences}, year = {2018}, volume = {373}, pages = {20170410} } |
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Gimenez, B.O., Jardine, K.J., Higuchi, N., Negrón-Juárez, R.I., Sampaio-Filho, I.d.J., Cobello, L.O., Fontes, C.G., Dawson, T.E., Varadharajan, C., Christianson, D.S., Spanner, G.C., Araújo, A.C., Warren, J.M., Newman, B.D., Holm, J.A., Koven, C.D., McDowell, N.G. and Chambers, J.Q. | Species-Specific Shifts in Diurnal Sap Velocity Dynamics and Hysteretic Behavior of Ecophysiological Variables During the 2015–2016 El Niño Event in the Amazon Forest | 2019 | Frontiers in Plant Science Vol. 10 |
article | DOI URL |
Abstract: Current climate change scenarios indicate warmer temperatures and the potential for more extreme droughts in the tropics, such that a mechanistic understanding of the water cycle from individual trees to landscapes is needed to adequately predict future changes in forest structure and function. In this study, we contrasted physiological responses of tropical trees during a normal dry season with the extreme dry season due to the 2015–2016 El Niño-Southern Oscillation (ENSO) event. We quantified high resolution temporal dynamics of sap velocity (V_s), stomatal conductance (g_s) and leaf water potential (Ψ_L) of multiple canopy trees, and their correlations with leaf temperature (T_leaf) and environmental conditions [direct solar radiation, air temperature (T_air) and vapor pressure deficit (VPD)]. The experiment leveraged canopy access towers to measure adjacent trees at the ZF2 and Tapajós tropical forest research (near the cities of Manaus and Santarém). The temporal difference between the peak of g_s (late morning) and the peak of VPD (early afternoon) is one of the major regulators of sap velocity hysteresis patterns. Sap velocity displayed species-specific diurnal hysteresis patterns reflected by changes in T_leaf. In the morning, T_leaf and sap velocity displayed a sigmoidal relationship. In the afternoon, stomatal conductance declined as T_leaf approached a daily peak, allowing Ψ_L to begin recovery, while sap velocity declined with an exponential relationship with T_leaf. In Manaus, hysteresis indices of the variables T_leaf-T_air and Ψ_L-T_leaf were calculated for different species and a significant difference (p textless 0.01, α = 0.05) was observed when the 2015 dry season (ENSO period) was compared with the 2017 dry season (“control scenario”). In some days during the 2015 ENSO event, T_leaf approached 40°C for all studied species and the differences between T_leaf and T_air reached as high at 8°C (average difference: 1.65 ± 1.07°C). Generally, T_leaf was higher than T_air during the middle morning to early afternoon, and lower than T_air during the early morning, late afternoon and night. Our results support the hypothesis that partial stomatal closure allows for a recovery in Ψ_L during the afternoon period giving an observed counterclockwise hysteresis pattern between Ψ_L and T_leaf. | |||||
BibTeX:
@article{gimenez_species-specific_2019, author = {Gimenez, Bruno O. and Jardine, Kolby J. and Higuchi, Niro and Negrón-Juárez, Robinson I. and Sampaio-Filho, Israel de Jesus and Cobello, Leticia O. and Fontes, Clarissa G. and Dawson, Todd E. and Varadharajan, Charuleka and Christianson, Danielle S. and Spanner, Gustavo C. and Araújo, Alessandro C. and Warren, Jeffrey M. and Newman, Brent D. and Holm, Jennifer A. and Koven, Charles D. and McDowell, Nate G. and Chambers, Jeffrey Q.}, title = {Species-Specific Shifts in Diurnal Sap Velocity Dynamics and Hysteretic Behavior of Ecophysiological Variables During the 2015–2016 El Niño Event in the Amazon Forest}, journal = {Frontiers in Plant Science}, year = {2019}, volume = {10}, url = {https://www.frontiersin.org/articles/10.3389/fpls.2019.00830}, doi = {https://doi.org/10.3389/fpls.2019.00830} } |
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Gimenez, B., Souza, D., Higuchi, N., Negrón-Juárez, R., Sampaio Filho, I., de Araújo, A., Lima, A., Gouveia Fontes, C., Jardine, K., Koven, C., Meng, L., Pastorello, G., McDowell, N. and Chambers, J. | Hysteresis between Leaf Water Potential, Stomatal Conductance, and Climate During and after a Drought Event in the Central Amazon [BibTeX] |
2023 | SSRN PRE PRINT Vol. PRE PRINT |
article | DOI |
BibTeX:
@article{gimenez_hysteresis_2023, author = {Gimenez, Bruno and Souza, Daisy and Higuchi, Niro and Negrón-Juárez, Robinson and Sampaio Filho, Israel and de Araújo, Alessandro and Lima, Adriano and Gouveia Fontes, Clarissa and Jardine, Kolby and Koven, Charles and Meng, Lin and Pastorello, Gilberto and McDowell, Nate and Chambers, Jeffrey}, title = {Hysteresis between Leaf Water Potential, Stomatal Conductance, and Climate During and after a Drought Event in the Central Amazon}, journal = {SSRN PRE PRINT}, year = {2023}, volume = {PRE PRINT}, doi = {https://doi.org/10.2139/ssrn.4436116} } |
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Gilbert, B., Laurance, W.F., Giles Leigh Jr., E. and Nascimento, H.E.M. | Can neutral theory predict the responses of amazonian tree communities to forest fragmentation? | 2006 | American Naturalist Vol. 168(3), pp. 304-317 |
article | DOI URL |
Abstract: We use Hubbell's neutral theory to predict the impact of habitat fragmentation on Amazonian tree communities. For forest fragments isolated for about two decades, we generate neutral predictions for local species extinction, changes in species composition within fragments, and increases in the probability that any two trees within a fragment are conspecific. We tested these predictions using fragment and intact forest data from the Biological Dynamics of Forest Fragments Project in central Amazonia. To simulate complete demographic isolation, we excluded immigrants-species absent from a fragment or intact forest plot in the initial census but present in its last census-from our tests. The neutral theory correctly predicted the rate of species extinction from different plots as a function of the diversity and mortality rate of trees in each plot. However, the rate of change in species composition was much faster than predicted in fragments, indicating that different tree species respond differently to environmental changes. This violates the key assumption of neutral theory. When immigrants were included in our calculations, they increased the disparity between predicted and observed changes in fragments. Overall, neutral theory accurately predicted the pace of local extinctions in fragments but consistently underestimated changes in species composition. | |||||
BibTeX:
@article{gilbert_can_2006, author = {Gilbert, Benjamin and Laurance, William F. and Giles Leigh, Jr., Egbert and Nascimento, Henrique E. M.}, title = {Can neutral theory predict the responses of amazonian tree communities to forest fragmentation?}, journal = {American Naturalist}, year = {2006}, volume = {168}, number = {3}, pages = {304--317}, note = {Edition: 2006/09/02}, url = {://WOS:000240600200003 http://www.jstor.org/stable/pdfplus/10.1086/506969.pdf?acceptTC=true}, doi = {https://doi.org/10.1086/506969} } |
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Gilardoni, S., Vignati, E., Marmer, E., Cavalli, F., Belis, C., Gianelle, V., Loureiro, A. and Artaxo, P. | Sources of carbonaceous aerosol in the Amazon basin | 2011 | Atmospheric Chemistry and Physics Vol. 11(6), pp. 2747-2764 |
article | DOI URL |
Abstract: The quantification of sources of carbonaceous aerosol is important to understand their atmospheric concentrations and regulating processes and to study possible effects on climate and air quality, in addition to develop mitigation strategies. In the framework of the European Integrated Project on Aerosol Cloud Climate Interactions (EUCAARI) fine (D(p) textless 2.5 mu m) and coarse (2.5 mu m textless Dp textless 10 mu m) aerosol particles were sampled from February to June (wet season) and from August to September (dry season) 2008 in the central Amazon basin. The mass of fine particles averaged 2.4 mu g m(-3) during the wet season and 4.2 mu g m(-3) during the dry season. The average coarse aerosol mass concentration during wet and dry periods was 7.9 and 7.6 mu g m(-3), respectively. The overall chemical composition of fine and coarse mass did not show any seasonality with the largest fraction of fine and coarse aerosol mass explained by organic carbon (OC); the average OC to mass ratio was 0.4 and 0.6 in fine and coarse aerosol modes, respectively. The mass absorbing cross section of soot was determined by comparison of elemental carbon and light absorption coefficient measurements and it was equal to 4.7 m(2) g(-1) at 637 nm. Carbon aerosol sources were identified by Positive Matrix Factorization (PMF) analysis of thermograms: 44% of fine total carbon mass was assigned to biomass burning, 43% to secondary organic aerosol (SOA), and 13% to volatile species that are difficult to apportion. In the coarse mode, primary biogenic aerosol particles (PBAP) dominated the carbonaceous aerosol mass. The results confirmed the importance of PBAP in forested areas. The source apportionment results were employed to evaluate the ability of global chemistry transport models to simulate carbonaceous aerosol sources in a regional tropical background site. The comparison showed an overestimation of elemental carbon (EC) by the TM5 model during the dry season and OC both during the dry and wet periods. The overestimation was likely due to the overestimation of biomass burning emission inventories and SOA production over tropical areas. | |||||
BibTeX:
@article{gilardoni_sources_2011, author = {Gilardoni, S. and Vignati, E. and Marmer, E. and Cavalli, F. and Belis, C. and Gianelle, V. and Loureiro, A. and Artaxo, P.}, title = {Sources of carbonaceous aerosol in the Amazon basin}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, number = {6}, pages = {2747--2764}, url = {://WOS:000288982300020}, doi = {https://doi.org/10.5194/acp-11-2747-2011} } |
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Giglio, L., Csiszar, I., Restas, A., Morisette, J.T., Schroeder, W., Morton, D. and Justice, C.O. | Active fire detection and characterization with the advanced spaceborne thermal emission and reflection radiometer (ASTER) | 2008 | Remote Sensing of Environment Vol. 112(6), pp. 3055-3063 |
article | DOI URL |
Abstract: We present an automated fire detection algorithm for the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor capable of mapping actively burning fires at 30-m spatial resolution. For daytime scenes, our approach uses near infrared and short-wave infrared reflectance imagery. For nighttime scenes a simple short wave infrared radiance threshold is applied. Based on a statistical analysis of 100 ASTER scenes, we established omission and commission error rates for nine different regions. In most regions the probability of detection was between 0.8 and 0.9. Probabilities of false alarm varied between 9 x 10(-8) (India) and 2x10(-5) (USA/Canada). In most cases, the majority of false fire pixels were linked to clusters of true fire pixels, suggesting that most false fire pixels occur along ambiguous fire boundaries. We next consider fire characterization, and formulate an empirical method for estimating fire radiative power (FRP), a measure of fire intensity, using three ASTER thermal infrared channels. We performed a preliminary evaluation of our retrieval approach using four prescribed fires which were active at the time of the Terra overpass for which limited ground-truth data were collected. Retrieved FRP was accurate to within 20%, with the exception of one fire partially obscured by heavy soot. (C) 2008 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{giglio_active_2008, author = {Giglio, Louis and Csiszar, Ivan and Restas, Agoston and Morisette, Jeffrey T. and Schroeder, Wilfrid and Morton, Douglas and Justice, Christopher O.}, title = {Active fire detection and characterization with the advanced spaceborne thermal emission and reflection radiometer (ASTER)}, journal = {Remote Sensing of Environment}, year = {2008}, volume = {112}, number = {6}, pages = {3055--3063}, url = {://WOS:000256986400026}, doi = {https://doi.org/10.1016/j.rse.2008.03.003} } |
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Gielow, R. and Michiles, A. | Transferências de momentum e perfis noturnos de velocidade do vento no interior de florestas da Amazônia [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial, pp. 375-378 |
article | |
BibTeX:
@article{gielow_transferencias_2007, author = {Gielow, R. and Michiles, A.A.S.}, title = {Transferências de momentum e perfis noturnos de velocidade do vento no interior de florestas da Amazônia}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial}, pages = {375--378} } |
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Gibbs, HK, Munger, J, Schelly, I, Morton, DC, Noojipady, P, Soares-Filho, B, Barreto, P, Micol, L, Walker, NF and Rausch, L | Extending Brazil’s Soy Moratorium [BibTeX] |
2015 | Science Vol. 347(6220), pp. 377-378 |
article | |
BibTeX:
@article{gibbs_hk_extending_2015, author = {Gibbs HK, Munger J, Schelly I, Morton DC, Noojipady P, Soares-Filho B, Barreto P, Micol L, Walker NF, Rausch L}, title = {Extending Brazil’s Soy Moratorium}, journal = {Science}, year = {2015}, volume = {347}, number = {6220}, pages = {377--378} } |
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Gibbon, A., Silman, M.R., Malhi, Y., Fisher, J.B., Meir, P., Zimmermann, M., Dargie, G.C., Farfan, W.R. and Garcia, K.C. | Ecosystem Carbon Storage Across the Grassland-Forest Transition in the High Andes of Manu National Park, Peru | 2010 | Ecosystems Vol. 13(7), pp. 1097-1111 |
article | DOI URL |
Abstract: Improved management of carbon storage by terrestrial biomes has significant value for mitigating climate change. The carbon value of such management has the potential to provide additional income to rural communities and provide biodiversity and climate adaptation co-benefits. Here, we quantify the carbon stores in a 49,300-ha landscape centered on the cloud forest-grassland transition of the high Andes in Manu National Park, Peru. Aboveground carbon densities were measured across the landscape by field sampling of 70 sites above and below the treeline. The forest near the treeline contained 63.4 +/- A 5.2 Mg C ha(-1) aboveground, with an additional 13.9 +/- A 2.8 Mg C ha(-1) estimated to be stored in the coarse roots, using a root to shoot ratio of 0.26. Puna grasslands near the treeline were found to store 7.5 +/- A 0.7 Mg C ha(-1) in aboveground biomass. Comparing our result to soil data gathered by Zimmermann and others (Ecosystems 13:62-74, 2010), we found the ratio of belowground:aboveground carbon decreased from 15.8 on the puna to 8.6 in the transition zone and 2.1 in the forest. No significant relationships were found between carbon densities and slope, altitude or fire disturbance history, though grazing (for puna) was found to reduce aboveground carbon densities significantly. We scaled our study sites to the study region with remote sensing observations from Landsat. The carbon sequestration potential of improved grazing management and assisted upslope treeline migration was also estimated. Afforestation of puna at the treeline could generate revenues of US $1,374 per ha over the project lifetime via commercialization of the carbon credits from gains in aboveground carbon stocks. Uncertainties in the fate of the large soil carbon stocks under an afforestation scenario exist. | |||||
BibTeX:
@article{gibbon_ecosystem_2010, author = {Gibbon, Adam and Silman, Miles R. and Malhi, Yadvinder and Fisher, Joshua B. and Meir, Patrick and Zimmermann, Michael and Dargie, Greta C. and Farfan, William R. and Garcia, Karina C.}, title = {Ecosystem Carbon Storage Across the Grassland-Forest Transition in the High Andes of Manu National Park, Peru}, journal = {Ecosystems}, year = {2010}, volume = {13}, number = {7}, pages = {1097--1111}, url = {://WOS:000282699200011}, doi = {https://doi.org/10.1007/s10021-010-9376-8} } |
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Giardina, F., Konings, A.G., Kennedy, D., Alemohammad, S., Oliveira, R., Uriarte, M. and Gentine, P. | Tall Amazonian forests are less sensitive to precipitation variability [BibTeX] |
2018 | Nature Geoscience Vol. 11, pp. 405-409 |
article | DOI |
BibTeX:
@article{giardina_tall_2018, author = {Giardina, F. and Konings, A. G. and Kennedy, D. and Alemohammad, S.H. and Oliveira, R.S. and Uriarte, M. and Gentine, P.}, title = {Tall Amazonian forests are less sensitive to precipitation variability}, journal = {Nature Geoscience}, year = {2018}, volume = {11}, pages = {405--409}, doi = {https://doi.org/10.1038/s41561-018-0133-5} } |
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Gevaerd, R. and Freitas, S. | Estimativa operacional da umidade do solo para iniciação de modelos de previsão numérica da atmosfera Parte I: Descrição da metodologia e validação [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 59-73 |
article | |
BibTeX:
@article{gevaerd_estimativa_2006, author = {Gevaerd, R. and Freitas, S.}, title = {Estimativa operacional da umidade do solo para iniciação de modelos de previsão numérica da atmosfera Parte I: Descrição da metodologia e validação}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {59--73} } |
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Gevaerd, F., Longo, S., Moreira, M., Silva-Dias, D.S., M.A.F., S.-D. and R., P.L. | Estimativa operacional da umidade do solo para iniciação de modelos de previsão numérica da atmosfera. Parte II: Impacto da umidade do solo e da parametrização de cumulus na simulação de uma linha seca [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 74-88 |
article | |
BibTeX:
@article{gevaerd_estimativa_2006-1, author = {Gevaerd, Freitas, S., Longo, M., Moreira, D.S., Silva-Dias, M.A.F., Silva-Dias, P.L., R.}, title = {Estimativa operacional da umidade do solo para iniciação de modelos de previsão numérica da atmosfera. Parte II: Impacto da umidade do solo e da parametrização de cumulus na simulação de uma linha seca}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {74--88} } |
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Germer, S., Zimmermann, A., Neill, C., Krusche, A.V. and Elsenbeer, H. | Disproportionate single-species contribution to canopy-soil nutrient flux in an Amazonian rainforest | 2012 | Forest Ecology and Management Vol. 267, pp. 40-49 |
article | DOI URL |
Abstract: Rainfall, throughfall and stemflow were monitored on an event basis in an undisturbed open tropical rainforest with a large number of palm trees located in the southwestern Amazon basin of Brazil. Stemflow samples were collected from 24 trees with a diameter at breast height (DBH) textgreater 5 cm, as well as eight young and four full-grown babassu palms (Attalea speciosa Mart.) for 5 weeks during the peak of the wet season. We calculated rainfall, throughfall and stemflow concentrations and fluxes of Na+, K+, Ca2+, Mg2+,, Cl-, SO42-, NO3- and H+ and stemflow volume-weighted mean concentrations and fluxes for three size classes of broadleaf trees and three size classes of palms. The concentrations of most solutes were higher in stemflow than in rainfall and increased with increasing tree and palm size. Concentration enrichments from rainfall to stemflow and throughfall were particularly high (81-fold) for NO3-. Stemflow fluxes of NO3- and H+ exceeded throughfall fluxes but stemflow fluxes of other solutes were less than throughfall fluxes. Stemflow solute fluxes to the forest soil were dominated by fluxes on babassu palms, which represented only 4% of total stem number and 10% of total basal area. For NO3-, stemflow contributed 51% of the total mass of nitrogen delivered to the forest floor (stemflow + throughfall) and represented more than a 2000-fold increase in NO3- flux compared what would have been delivered by rainfall alone on the equivalent area. Because these highly localized fluxes of both water and NO3- persist in time and space, they have the potential to affect patterns of soil moisture, microbial populations and other features of soil biogeochemistry conducive to the creation of hotspots for nitrogen leaching and denitrification, which could amount to an important fraction of total ecosystem fluxes. Because these hotspots occur over very small areas, they have likely gone undetected in previous studies and need to be considered as an important feature of the biogeochemistry of palm-rich tropical forest. (C) 2011 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{germer_disproportionate_2012, author = {Germer, S. and Zimmermann, A. and Neill, C. and Krusche, A. V. and Elsenbeer, H.}, title = {Disproportionate single-species contribution to canopy-soil nutrient flux in an Amazonian rainforest}, journal = {Forest Ecology and Management}, year = {2012}, volume = {267}, pages = {40--49}, url = {://000301219000005}, doi = {https://doi.org/10.1016/j.foreco.2011.11.041} } |
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Germer, S., Neill, C., Vetter, T., Chaves, J., Krusche, A.V. and Elsenbeer, H. | Implications of long-term land-use change for the hydrology and solute budgets of small catchments in Amazonia | 2009 | Journal of Hydrology Vol. 364(3-4), pp. 349-363 |
article | DOI URL |
Abstract: The replacement of undisturbed tropical forest with cattle pasture has the potential to greatly modify the hydrology of small watersheds and the fluxes of solutes. We examined the fluxes of water, Cl(-), NO(3)(-)-N: SO(4)(2--)-S, NH(4)(+)-N, Na(+), K(+), Mg(2+) and Ca(2+) in different flow paths in similar to 1 ha catchments of undisturbed open tropical rainforest and a 20 year-old pasture established from forest in the southwestern Brazilian Amazon state of Rondonia. Storm flow discharge was 18% of incident rainfall in pasture, but only 1% in forest. Quickflow predominated over baseflow in both catchments and in both wet and dry seasons. In the pasture, groundwater and quickflow were important flow paths for the export of all solutes. In the forest, quickflow was important for NO(3)(-)-N export, but all other solutes were exported primarily by groundwater outflow. Both catchments were sinks for SO(4)(2-)-S and Ca(2+), and sources of Na(+). The pasture catchment also lost K(+) and Mg(2+) because of higher overland flow frequency and volume and to cattle excrement. These results show that forest clearing dramatically influences small watershed hydrology by increasing quickflow and water export to streams. They also indicate that tropical forest watersheds are highly conservative for most solutes but that pastures continue to lose important cations even decades after deforestation and pasture establishment. (c) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{germer_implications_2009, author = {Germer, Sonja and Neill, Christopher and Vetter, Tobias and Chaves, Joaquin and Krusche, Alex V. and Elsenbeer, Helmut}, title = {Implications of long-term land-use change for the hydrology and solute budgets of small catchments in Amazonia}, journal = {Journal of Hydrology}, year = {2009}, volume = {364}, number = {3-4}, pages = {349--363}, url = {://WOS:000263011700014}, doi = {https://doi.org/10.1016/j.jhydrol.2008.11.013} } |
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Germer, S., Neill, C., Krusche, A.V., Gouveia, S.C.N. and Elsenbeer, H. | Seasonal and within-event dynamics of rainfall and throughfall chemistry in an open tropical rainforest in Rondonia, Brazil | 2007 | Biogeochemistry Vol. 86(2), pp. 155-174 |
article | DOI URL |
Abstract: Prolonged dry periods, and increasingly the generation of smoke and dust in partially-deforested regions, can influence the chemistry of rainfall and throughfall in moist tropical forests. We investigated rainfall and throughfall chemistry in a palm-rich open tropical rainforest in the southwestern Brazilian Amazon state of Rondonia, where precipitation averages 2300 mm year(-1) with a marked seasonal pattern, and where the fragmentation of remaining forest is severe. Covering the transition from dry to wet season (TDWS) and the wet season (WS) of 2004-2005, we sampled 42 rainfall events on event basis as well as 35 events on a within-event basis, and measured concentrations of DOC, Na+, K+, Ca2+, Mg2+, NH4+ , Cl-, SO42- , NO3- and pH in rainfall and throughfall. We found strong evidence of both seasonal and within-event solute rainfall concentration dynamics. Seasonal volume-weighted mean (VWMS) concentrations in rainfall of DOC, K+, Ca2+, Mg2+, NH4+ , SO42- and NO3- were significantly higher in the TDWS than the WS, while VWMS concentrations in throughfall were significantly higher for all solutes except DOC. Patterns were generally similar within rain events, with solute concentrations declining sharply during the first few millimeters of rainfall. Rainfall and throughfall chemistry dynamics appeared to be strongly influenced by forest and pasture burning and a regional atmosphere rich in aerosols at the end of the dry season. These seasonal and within-event patterns of rainfall and throughfall chemistry were stronger than those recorded in central Amazonia, where the dry season is less pronounced and where regional deforestation is less severe. Fragmentation and fire in Rondonia now appear to be altering the patterns in which solutes are delivered to remaining moist tropical forests. | |||||
BibTeX:
@article{germer_seasonal_2007, author = {Germer, Sonja and Neill, Christopher and Krusche, Alex V. and Gouveia, Sergio C. Neto and Elsenbeer, Helmut}, title = {Seasonal and within-event dynamics of rainfall and throughfall chemistry in an open tropical rainforest in Rondonia, Brazil}, journal = {Biogeochemistry}, year = {2007}, volume = {86}, number = {2}, pages = {155--174}, url = {://WOS:000250204700003}, doi = {https://doi.org/10.1007/s10533-007-9152-9} } |
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Germer, S., Neill, C., Krusche, A.V. and Elsenbeer, H. | Influence of land-use change on near-surface hydrological processes: Undisturbed forest to pasture | 2010 | Journal of Hydrology Vol. 380(3-4), pp. 473-480 |
article | DOI URL |
Abstract: Soil compaction that follows the clearing of tropical forest for cattle pasture is associated with lower soil hydraulic conductivity and increased frequency and volume of overland flow. We investigated the frequency of perched water tables, overland flow and stormflow in an Amazon forest and in an adjacent 25-year-old pasture cleared from the same forest. We compared the results with the frequencies of these phenomena estimated from comparisons of rainfall intensity and soil hydraulic conductivity. The frequency of perched water tables based on rainfall intensity and soil hydraulic conductivity was expected to double in pasture compared with forest. This corresponded closely with an approximate doubling of the frequency of stormflow and overland flow in pasture. In contrast, the stormflow volume in pasture increased 17-fold. This disproportional increase of stormflow resulted from overland flow generation over large areas of pasture, while overland flow generation in the forest was spatially limited and was observed only very near the stream channel. In both catchments, stormflow was generated by saturation excess because of perched water tables and near-surface groundwater levels. Stormflow was occasionally generated in the forest by rapid return flow from macropores, while slow return flow from a continuous perched water table was more common in the pasture. These results suggest that deforestation for pasture alters fundamental mechanisms of stormflow generation and may increase runoff volumes over wide regions of Amazonia. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{germer_influence_2010, author = {Germer, S. and Neill, C. and Krusche, A. V. and Elsenbeer, H.}, title = {Influence of land-use change on near-surface hydrological processes: Undisturbed forest to pasture}, journal = {Journal of Hydrology}, year = {2010}, volume = {380}, number = {3-4}, pages = {473--480}, url = {://000274497100020}, doi = {https://doi.org/10.1016/j.jhydrol.2009.11.022} } |
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Germer, S., Elsenbeer, H. and Moraes, J.M. | Throughfall and temporal trends of rainfall redistribution in an open tropical rainforest, south-western Amazonia (Rondonia, Brazil) | 2006 | Hydrology and Earth System Sciences Vol. 10(3), pp. 383-393 |
article | URL |
Abstract: Throughfall volumes and incident rainfall were measured between 23 August and 2 December 2004 as well as from 6 January to 15 April 2005 for individual rain events of differing intensities and magnitudes in an open tropical rainforest in Rondonia, Brazil. Temporal patterns of throughfall spatial variability were examined. Estimated interception was compared to modeled interception obtained by applying the revised Gash model in order to identify sources of throughfall variability in open tropical rainforests. Gross precipitation of 97 events amounted to 1309 mm, 89 +/- 5.6% (S.E.) of which reached the forest floor as throughfall. The redistribution of water within the canopy was highly variable in time, which we attribute to the high density of babassu palms (Orbignya phalerata), their seasonal leaf growth, and their conducive morphology. We identified a 10-min rainfall intensity threshold of 30 mm h(-1) above which interception was highly variable. This variability is amplified by funneling and shading effects of palms. This interaction between a rainfall variable and vegetation characteristics is relevant for understanding the hydrology of all tropical rainforests with a high palm density. | |||||
BibTeX:
@article{germer_throughfall_2006, author = {Germer, S. and Elsenbeer, H. and Moraes, J. M.}, title = {Throughfall and temporal trends of rainfall redistribution in an open tropical rainforest, south-western Amazonia (Rondonia, Brazil)}, journal = {Hydrology and Earth System Sciences}, year = {2006}, volume = {10}, number = {3}, pages = {383--393}, url = {://WOS:000239729900006} } |
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Germano, M.F., Vitorino, M.I., Cohen, J.C.P., Costa, G.B., Souto, J.I.d.O., Rebelo, M.T.C. and Sousa, A.M.L.d. | Analysis of the breeze circulations in Eastern Amazon: an observational study [BibTeX] |
2017 | Atmospherics Science Letters Vol. 18(2), pp. 67-75 |
article | DOI |
BibTeX:
@article{germano_analysis_2017, author = {Germano, Michell Fontenelle and Vitorino, Maria Isabel and Cohen, Júlia Clarinda Paiva and Costa, Gabriel Brito and Souto, Jefferson Inayan de Oliveira and Rebelo, Mayse Thais Correa and Sousa, Adriano Marlisom Leão de}, title = {Analysis of the breeze circulations in Eastern Amazon: an observational study}, journal = {Atmospherics Science Letters}, year = {2017}, volume = {18}, number = {2}, pages = {67--75}, doi = {https://doi.org/10.1002/asl.726} } |
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Germano, V., Costa, M.I., Souza, G.B., A.M.L. de, S. and J.I.O., M. | Variabilidade atmosférica da precipitação associada com as circulações de brisas marítimas e terrestres no nordeste do estado do Pará, Brasil [BibTeX] |
2017 | Boletim Museu Paraense Emílio Goeldi Ciencias Naturais Vol. 11(3), pp. 303-312 |
article | |
BibTeX:
@article{germano_variabilidade_2017, author = {Germano, Vitorino, M.I., Costa, G.B., Souza, A.M.L. de, Souto, J.I.O., M.F.}, title = {Variabilidade atmosférica da precipitação associada com as circulações de brisas marítimas e terrestres no nordeste do estado do Pará, Brasil}, journal = {Boletim Museu Paraense Emílio Goeldi Ciencias Naturais}, year = {2017}, volume = {11}, number = {3}, pages = {303--312} } |
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Gerken, T., Wei, D., Chase, R.J., Fuentes, J.D., Schumacher, C., Machado, L.A., Andreoli, R.V., Chamecki, M., Souza, R.A.F.d., Freire, L.S., Jardine, A.B., Manzi, A.O., Santos, R.M.N.d., von Randow, C., Costa, P.d.S., Stoy, P.C., Tóta, J. and Trowbridge, A.M. | Downward transport of ozone rich air and implications for atmospheric chemistry in the Amazon rainforest [BibTeX] |
2016 | Atmospheric Environment Vol. 12A, pp. 64-76 |
article | |
BibTeX:
@article{gerken_downward_2016, author = {Gerken, Tobias and Wei, Dandan and Chase, Randy J. and Fuentes, Jose D. and Schumacher, Courtney and Machado, Luiz A.T. and Andreoli, Rita V. and Chamecki, Marcelo and Souza, Rodrigo A. Ferreira de and Freire, Livia S. and Jardine, Angela B. and Manzi, Antonio O. and Santos, Rosa M. Nascimento dos and von Randow, Celso and Costa, Patrícia dos Santos and Stoy, Paul C. and Tóta, Julio and Trowbridge, Amy M.}, title = {Downward transport of ozone rich air and implications for atmospheric chemistry in the Amazon rainforest}, journal = {Atmospheric Environment}, year = {2016}, volume = {12A}, pages = {64--76} } |
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Gerken, T., Ruddell, B., Fuentes, J.D., Araújo, A., Brunsell, N.A., Maia, J.F., Manzi, A., Mercer, J., Santos, R.N., Randow, C.v. and Stoy, P.C. | Investigating the mechanisms responsible for the lack of surface energy balance closure in a central Amazonian tropical rainforest [BibTeX] |
2018 | Agricultural and Forest Meteorology Vol. 255, pp. 92-103 |
article | |
BibTeX:
@article{gerken_investigating_2018, author = {Gerken, T. and Ruddell, B.L. and Fuentes, J. D. and Araújo, A. and Brunsell, N. A. and Maia, J. F. and Manzi, A. and Mercer, J. and Santos, R. N.dos and Randow, C. von and Stoy, P. C.}, title = {Investigating the mechanisms responsible for the lack of surface energy balance closure in a central Amazonian tropical rainforest}, journal = {Agricultural and Forest Meteorology}, year = {2018}, volume = {255}, pages = {92--103} } |
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Gergel, S.E., Turner, M.G., Miller, J.R., Melack, J.M. and Stanley, E.H. | Landscape indicators of human impacts to riverine systems | 2002 | Aquatic Sciences Vol. 64(2), pp. 118-128 |
article | DOI URL |
Abstract: Detecting human impacts on riverine systems is challenging because of the diverse biological, chemical, hydrological and geophysical components that must be assessed. We briefly review the chemical, biotic, hydrologic and physical habitat assessment approaches commonly used in riverine systems. We then discuss how landscape indicators can be used to assess the status of rivers by quantifying land cover changes in the surrounding catchment, and contrast landscape-level indicators with the more traditionally used approaches. Landscape metrics that describe the amount and arrangement of human-altered land in a catchment provide a direct way to measure human impacts and can be correlated with many traditionally used riverine indicators, such as water chemistry and biotic variables. The spatial pattern of riparian habitats may also be an especially powerful landscape indicator because the variation in length, width, and gaps of riparian buffers influences their effectiveness as nutrient sinks. The width of riparian buffers is also related to the diversity of riparian bird species. Landscape indicators incorporating historical land use may also hold promise for predicting and assessing the status of riverine systems. Importantly, the relationship between an aquatic system attribute and a landscape indicator may be non-linear and thus exhibit threshold responses. This has become especially apparent from landscape indicators quantifying the percent impervious surface (or urban areas) in a watershed, a landscape indicator of hydrologic and geomorphic change. | |||||
BibTeX:
@article{gergel_landscape_2002, author = {Gergel, S. E. and Turner, M. G. and Miller, J. R. and Melack, J. M. and Stanley, E. H.}, title = {Landscape indicators of human impacts to riverine systems}, journal = {Aquatic Sciences}, year = {2002}, volume = {64}, number = {2}, pages = {118--128}, url = {://WOS:000176983900002}, doi = {https://doi.org/10.1007/s00027-002-8060-2} } |
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Gerbig, C., Lin, J.C., Wofsy, S.C., Daube, B.C., Andrews, A.E., Stephens, B.B., Bakwin, P.S. and Grainger, C.A. | Toward constraining regional-scale fluxes of CO2 with atmospheric observations over a continent: 1. Observed spatial variability from airborne platforms | 2003 | Journal of Geophysical Research-Atmospheres Vol. 108(D24) |
article | DOI URL |
Abstract: We analyze the spatial variability of CO2 measurements from aircraft platforms, including extensive observations acquired over North America during the CO2 Budget and Rectification Airborne (COBRA) study in 2000. The COBRA data set is unique in its dense spatial coverage and extensive profiling in the lower atmosphere. Strong signatures of CO2 fluxes at the land surface were observed in the active and relic mixed layers of the atmosphere (up to similar to20 ppm gradients). Free tropospheric CO2 exhibited significantly less variability except in areas affected by convective transport. Statistical analyses of the COBRA data indicate that CO2 mixed-layer averages can be determined from vertical profiles with an accuracy of approximately +/-0.2 ppm, limited by atmospheric variance. Analysis of the associated representation error suggests that models require horizontal resolution smaller than similar to30 km to fully resolve spatial variations of atmospheric CO2 in the boundary layer over the continent. To provide a global context for these data, we analyzed the GLOBALVIEW marine boundary layer (MBL) reference CO2. Comparison of the MBL reference with extensive aircraft data extending over 20 years, covering the whole troposphere over the northern Pacific, shows significant seasonal biases of up to 2 ppm in the free troposphere, indicating that the MBL reference is a suitable boundary condition only for some applications. The spatial variability of CO2 revealed by the COBRA-2000 calls for a suitable analysis framework to derive regional and continental fluxes, presented in a companion paper. The problem requires boundary conditions constrained by both surface and upper tropospheric observations and constraints on terrestrial fluxes that exploit the information content of the highly variable CO2 distribution over land. | |||||
BibTeX:
@article{gerbig_toward_2003, author = {Gerbig, C. and Lin, J. C. and Wofsy, S. C. and Daube, B. C. and Andrews, A. E. and Stephens, B. B. and Bakwin, P. S. and Grainger, C. A.}, title = {Toward constraining regional-scale fluxes of CO2 with atmospheric observations over a continent: 1. Observed spatial variability from airborne platforms}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2003}, volume = {108}, number = {D24}, url = {://WOS:000187858300001}, doi = {https://doi.org/10.1029/2002jd003018} } |
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Gerbig, C., Lin, J.C., Munger, J.W. and Wofsy, S.C. | What can tracer observations in the continental boundary layer tell us about surface-atmosphere fluxes? | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 539-554 |
article | URL |
Abstract: We analyze the potential for inferring spatially resolved surface fluxes from atmospheric tracer observations within the mixed layer, such as from monitoring towers, using a receptor oriented transport model ( Stochastic Time-Inverted Lagrangian Transport model - STILT) coupled to a simple biosphere in which CO(2) fluxes are represented as functional responses to environmental drivers ( radiation and temperature). Transport and biospheric fluxes are coupled on a dynamic grid using a polar projection with high horizontal resolution (similar to 20 km) in near field, and low resolution far away ( as coarse as 2000 km), reducing the number of surface pixels without significant loss of information. To test the system, and to evaluate the errors associated with the retrieval of fluxes from atmospheric observations, a pseudo data experiment was performed. A large number of realizations of measurements ( pseudo data) and a priori fluxes were generated, and for each case spatially resolved fluxes were retrieved. Results indicate strong potential for high resolution retrievals based on a network of tall towers, subject to the requirement of correctly specifying the a priori uncertainty covariance, especially the off diagonal elements that control spatial correlations. False assumptions about the degree to which the uncertainties in the a priori fluxes are spatially correlated may lead to a strong underestimation of uncertainties in the retrieved fluxes, or, equivalently, to biased retrievals. The framework presented here, however, allows a conservative choice of the off diagonal elements that avoids biasing the retrievals. | |||||
BibTeX:
@article{gerbig_what_2006, author = {Gerbig, C. and Lin, J. C. and Munger, J. W. and Wofsy, S. C.}, title = {What can tracer observations in the continental boundary layer tell us about surface-atmosphere fluxes?}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {539--554}, url = {://WOS:000235529500001} } |
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Gatti, LV, Miller, JB, Doughty, CE, Malhi, Y, Domingues, LG, Basso, LS, Martinewski, A, Correia, CSC, Borges, VF, Freitas, S, Braz, R, Anderson, LO, Rocha, H, Grace, J, Phillips OL & Lloyd, J. and Gloor, M | Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements [BibTeX] |
2014 | Nature Vol. 506(7486), pp. 76-80 |
article | DOI |
BibTeX:
@article{gatti_lv_drought_2014, author = {Gatti LV, Miller JB, Doughty CE, Malhi Y, Domingues LG, Basso LS, Martinewski A, Correia CSC, Borges VF, Freitas S, Braz R, Anderson LO, Rocha H, Grace J, Phillips OL & Lloyd J., Gloor M}, title = {Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements}, journal = {Nature}, year = {2014}, volume = {506}, number = {7486}, pages = {76--80}, doi = {https://doi.org/10.1038/nature12957} } |
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Gatti, L.V., Mozeto, A.A. and Artaxo, P. | Trace elements in lake sediments measured by the PIXE technique | 1999 | Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms Vol. 150(1-4), pp. 298-305 |
article | DOI URL |
Abstract: Lakes are ecosystems where there is a great potential of metal accumulation in sediments due to their depositional characteristics. Total concentration of trace elements was measured on a 50 cm long sediment core from the Infernao Lake, that is an oxbow lake of the Moji-Guacu River basin, in the state of Sao Paulo, Brazil. Dating of the core shows up to 180 yrs old sediment layers. The use of the PIXE technique for elemental analysis avoids the traditional acid digestion procedure common in other techniques. The multielemental characteristic of PINE allows a simultaneous determination of about 20 elements in the sediment samples, such as, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Zr, Ba, and Pb. Average values for the elemental composition were found to be similar to the bulk crustal composition. The lake flooding pattern strongly influences the time series of the elemental profiles. Factor analysis of the elemental variability shows five factors. Two of the factors represent the mineralogical matrix, and others represent the organic component, a factor with lead, and another loaded with chromium, The mineralogical component consists of elements such as, Fe, Al, V, Ti, Mn, Ni, K, Zr, Sr, Cu and Zn. The variability of Si is explained by two distinct factors, because it is influenced by two different sources, aluminum-silicates and quartz, and the effect of inundation are different for each other. The organic matter is strongly associated with calcium, and also bounded with S, Zn, Cu and P. Lead and chromium appears as separated factors, although it is not clear the evidences for their anthropogenic origin. The techniques developed for sample preparation and PIXE analysis was proven as advantageous and provided very good reproducibility and accuracy. (C) 1999 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{gatti_trace_1999, author = {Gatti, L. V. and Mozeto, A. A. and Artaxo, P.}, title = {Trace elements in lake sediments measured by the PIXE technique}, journal = {Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms}, year = {1999}, volume = {150}, number = {1-4}, pages = {298--305}, url = {://WOS:000080056500050}, doi = {https://doi.org/10.1016/s0168-583x(98)01079-9} } |
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Gatti, L.V., Miller, J.B., D'Amelio, M.T.S., Martinewski, A., Basso, L.S., Gloor, M.E., Wofsy, S. and Tans, P. | Vertical profiles of CO(2) above eastern Amazonia suggest a net carbon flux to the atmosphere and balanced biosphere between 2000 and 2009 | 2010 | Tellus Series B-Chemical and Physical Meteorology Vol. 62(5), pp. 581-594 |
article | DOI URL |
Abstract: From 2000 until January 2010 vertical profiles were collected above eastern Amazonia to help determine regional-scale (similar to 105-106 km2) fluxes of carbon cycle-related greenhouse gases. Samples were collected aboard light aircraft between the surface and 4.3 km and a column integration technique was used to determine the CO(2) flux. Measured CO(2) profiles were differenced from the CO(2) background determined from measurements in the tropical Atlantic. The observed annual flux between the coast and measurement sites was 0.40 +/- 0.27 gC m-2 d-1 (90% confidence interval using a bootstrap analysis). The wet season (January-June) mean flux was 0.44 +/- 0.38 gC m-2 d-1 (positive fluxes defined as a source to the atmosphere) and the dry season mean flux was 0.35 +/- 0.17 gC m-2 d-1 (July-December). The observed flux variability is high, principally in the wet season. The influence of biomass burning has been removed using co-measured CO, and revealed the presence of a significant dry season sink. The annual mean vegetation flux, after the biomass burning correction, was 0.02 +/- 0.27 gC m-2 d-1, and a clear sink was observed between August and November of -0.70 +/- 0.21 gC m-2 d-1 where for all of the dry season it was -0.24 +/- 0.17 gC m-2 d-1. | |||||
BibTeX:
@article{gatti_vertical_2010, author = {Gatti, L. V. and Miller, J. B. and D'Amelio, M. T. S. and Martinewski, A. and Basso, L. S. and Gloor, M. E. and Wofsy, S. and Tans, P.}, title = {Vertical profiles of CO(2) above eastern Amazonia suggest a net carbon flux to the atmosphere and balanced biosphere between 2000 and 2009}, journal = {Tellus Series B-Chemical and Physical Meteorology}, year = {2010}, volume = {62}, number = {5}, pages = {581--594}, url = {://WOS:000283167300021}, doi = {https://doi.org/10.1111/j.1600-0889.2010.00484.x} } |
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Gash, J.H.C., Marengo, J.A. and Huntingford, C. | Preface [BibTeX] |
2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 3-3 |
article | DOI URL |
BibTeX:
@article{gash_preface_2004, author = {Gash, J. H. C. and Marengo, J. A. and Huntingford, C.}, title = {Preface}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {3--3}, url = {://WOS:000222024700002}, doi = {https://doi.org/10.1007/s00704-004-0040-0} } |
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Gash, J.H.C., Huntingford, C., Marengo, J.A., Betts, R.A., Cox, P.M., Fisch, G., Fu, R., Gandu, A.W., Harris, P.P., Machado, L.A.T., von Randow, C. and Dias, M.A.S. | Amazonian climate: results and future research | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 187-193 |
article | DOI URL |
Abstract: Some of the results from the climate component of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), which are presented in this Special Issue are summarised. Recent advances in Amazonian climate modelling are also discussed. There is a range of papers which fall into three groups: surface fluxes and boundary layer growth; convection, clouds and rainfall; and climate modelling. The new insight given by this work is discussed and an argument is made for future research to employ a wider approach to Amazonian climate modelling. | |||||
BibTeX:
@article{gash_amazonian_2004, author = {Gash, J. H. C. and Huntingford, C. and Marengo, J. A. and Betts, R. A. and Cox, P. M. and Fisch, G. and Fu, R. and Gandu, A. W. and Harris, P. P. and Machado, L. A. T. and von Randow, C. and Dias, M. A. S.}, title = {Amazonian climate: results and future research}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {187--193}, url = {://WOS:000222024700014 http://www.springerlink.com/content/02acmu95fv1dhrt2/fulltext.pdf}, doi = {https://doi.org/10.1007/s00704-004-0052-9} } |
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Gascon, C., Williamson, G.B. and da Fonseca, G.A.B. | Ecology - Receding forest edges and vanishing reserves [BibTeX] |
2000 | Science Vol. 288(5470), pp. 1356-1358 |
article | DOI URL |
BibTeX:
@article{gascon_ecology_2000, author = {Gascon, C. and Williamson, G. B. and da Fonseca, G. A. B.}, title = {Ecology - Receding forest edges and vanishing reserves}, journal = {Science}, year = {2000}, volume = {288}, number = {5470}, pages = {1356--1358}, note = {Edition: 2000/06/10}, url = {://WOS:000087270900032}, doi = {https://doi.org/10.1126/science.288.5470.1356} } |
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Gascon, C., Mesquita, R. and Higuchi, N. | Logging on in the rain forests [BibTeX] |
1998 | Science Vol. 281(5382), pp. 1453-1453 |
article | URL |
BibTeX:
@article{gascon_logging_1998, author = {Gascon, C. and Mesquita, R. and Higuchi, N.}, title = {Logging on in the rain forests}, journal = {Science}, year = {1998}, volume = {281}, number = {5382}, pages = {1453--1453}, url = {://WOS:000075738100019} } |
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Gascon, C., Lovejoy, T.E., Bierregaard, R.O., Malcolm, J.R., Stouffer, P.C., Vasconcelos, H.L., Laurance, W.F., Zimmerman, B., Tocher, M. and Borges, S. | Matrix habitat and species richness in tropical forest remnants | 1999 | Biological Conservation Vol. 91(2-3), pp. 223-229 |
article | DOI URL |
Abstract: The abilities of species to use the matrix of modified habitats surrounding forest fragments may affect their vulnerability in fragmented landscapes. We used long-term (up to 19-year) studies of four animal groups in central Amazonia to test whether species' abundances in the matrix were correlated with their relative extinction proneness in forest fragments. The four groups, birds, frogs, small mammals, and ants, had varying overall responses to fragmentation: species richness of small mammals and frogs increased after fragment isolation, whereas that of birds and ants decreased. For all four groups, a high proportion of nominally primary-forest species were detected in matrix habitats, with 8-25% of species in each group found exclusively in the matrix. The three vertebrate groups (birds, small mammals, frogs) exhibited positive and significant correlations between matrix abundance and vulnerability to fragmentation, suggesting that species that avoid the matrix tend to decline or disappear in fragments, while those that tolerate or exploit the matrix often remain stable or increase. These results highlight the importance of the matrix in the dynamics and composition of vertebrate communities in tropical forest remnants, and have important implications for the management of fragmented landscapes. (C) 1999 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{gascon_matrix_1999, author = {Gascon, C. and Lovejoy, T. E. and Bierregaard, R. O. and Malcolm, J. R. and Stouffer, P. C. and Vasconcelos, H. L. and Laurance, W. F. and Zimmerman, B. and Tocher, M. and Borges, S.}, title = {Matrix habitat and species richness in tropical forest remnants}, journal = {Biological Conservation}, year = {1999}, volume = {91}, number = {2-3}, pages = {223--229}, url = {://WOS:000083531100015}, doi = {https://doi.org/10.1016/s0006-3207(99)00080-4} } |
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Gardner, T., Ferreira, J., Barlow, J., Lees, A., Parry, l., Vieira, I., Berenguer, E., Abramovay, R., Aleixo, A., Andretti, C., Aragao, l.E., Araujo, I.d., Avila, W.S., Bardgett, R., Batistella, M., Begotti, R., Beldini, T.d., D.E., BLAS, Braga, R., Braga, D., De brito, J.G., de Camargo, P., Campos dos Santos, F., de Oliveira, V., Cordeiro, A. and al. , e. | A social and ecological assessment of tropical land uses at multiple scales: the Sustainable Amazon Network. [BibTeX] |
2013 | Philosophical Transactions of the Royal Society B: Biological Sciences Vol. 368, pp. 20120166-20120166 |
article | |
BibTeX:
@article{gardner_social_2013, author = {Gardner, T.A. and Ferreira, J. and Barlow, J. and Lees, A.C. and Parry, l. and Vieira, I.C.G. and Berenguer, E. and Abramovay, R. and Aleixo, A. and Andretti, C. and Aragao, l. E.O.C. and Araujo, I. de and Avila, W. S. and Bardgett, R.D. and Batistella, M. and Begotti, R.A. and Beldini, T. de and BLAS, D.E. and Braga, R.F. and Braga, D.D.L. and De brito, J. G. and de Camargo, P.B. and Campos dos Santos, F. and de Oliveira, V.C. and Cordeiro, A.C.N. and al., et}, title = {A social and ecological assessment of tropical land uses at multiple scales: the Sustainable Amazon Network.}, journal = {Philosophical Transactions of the Royal Society B: Biological Sciences}, year = {2013}, volume = {368}, pages = {20120166--20120166} } |
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Garcia-Montiel, D.C., Steudler, P.A., Piccolo, M.C., Melillo, J.M., Neill, C. and Cerri, C.C. | Controls on soil nitrogen oxide emissions from forest and pastures in the Brazilian Amazon | 2001 | Global Biogeochemical Cycles Vol. 15(4), pp. 1021-1030 |
article | DOI URL |
Abstract: Soil N dynamics and water content are important controls of nitrous (N(2)O) and nitric (NO) oxide emissions from tropical soils. We used a chronosequence of one forest and six pastures to investigate how soil N availability and soil moisture content affect emissions of N(2)O and NO. Forest soils had high N availability and large N oxide emissions. Forest conversion to pasture decreased N availability and N oxide emissions. In the forest where N availability was high, seasonal changes in soils moisture led to higher N(2)O fluxes during the wet season, but higher NO fluxes during the dry season. Soil water content exerted the largest control on N(2)O emissions, which seemed to be determined by a threshold value of approximately 29-30%, below which N(2)O emissions were nearly constant and above which they increased (Figure 5a). In pastures, where low N availability constrains N(2)O and NO fluxes, soil water content has a minor influence on N oxide emissions. | |||||
BibTeX:
@article{garcia-montiel_controls_2001, author = {Garcia-Montiel, D. C. and Steudler, P. A. and Piccolo, M. C. and Melillo, J. M. and Neill, C. and Cerri, C. C.}, title = {Controls on soil nitrogen oxide emissions from forest and pastures in the Brazilian Amazon}, journal = {Global Biogeochemical Cycles}, year = {2001}, volume = {15}, number = {4}, pages = {1021--1030}, url = {://WOS:000172755300019}, doi = {https://doi.org/10.1029/2000gb001349} } |
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Garcia-Montiel, D.C., Steudler, P.A., Piccolo, M., Neill, C., Melillo, J. and Cerri, C.C. | Nitrogen oxide emissions following wetting of dry soils in forest and pastures in Rondonia, Brazil | 2003 | Biogeochemistry Vol. 64(3), pp. 319-336 |
article | DOI URL |
Abstract: Rains at the end of the dry season can trigger increases in emissions of nitric oxide (NO) and nitrous oxide from forest and pasture soils in the Amazon Basin. The relative importance of the rain-stimulated emissions in the seasonal and annual budgets of these nitrogen gases for forests and pastures in the western Amazon is not well established. We measured soil emissions of NO and N2O from a forest and two pastures, 11 and 26 years old, after a simulated rain event. Wetting the soil resulted in very small pulses of NO or N2O from forest soils and no significant NO or N2O pulses from the pastures. We estimated that in the forest, the amounts of each gas emitted from pulses during the dry to wet transition period represented 3.4% of the NO and 1.8% of the N2O dry-season emissions, but amounted to less than 2% of the annual emissions of either gas. Total N oxide emissions of 5.6 kg N/ha/yr from the forest were nearly evenly divided between NO (42%) and N2O (58%). The emissions of NO were evenly distributed over the wet and dry seasons, while over 84% N2O fluxes occurred during the wet season. | |||||
BibTeX:
@article{garcia-montiel_nitrogen_2003, author = {Garcia-Montiel, D. C. and Steudler, P. A. and Piccolo, M. and Neill, C. and Melillo, J. and Cerri, C. C.}, title = {Nitrogen oxide emissions following wetting of dry soils in forest and pastures in Rondonia, Brazil}, journal = {Biogeochemistry}, year = {2003}, volume = {64}, number = {3}, pages = {319--336}, url = {://WOS:000184414800002}, doi = {https://doi.org/10.1023/a:1024968802018} } |
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Garcia-Montiel, D.C., Neill, C., Melillo, J., Thomas, S., Steudler, P.A. and Cerri, C.C. | Soil phosphorus transformations following forest clearing for pasture in the Brazilian Amazon | 2000 | Soil Science Society of America Journal Vol. 64(5), pp. 1792-1804 |
article | URL |
Abstract: Phosphorus limits grass production in pastures planted on most cleared moist tropical forest, but little is known about soil P dynamics in these ecosystems, We describe changes to total P and different soil P fractions that occurred after the conversion of forest to pasture in the Brazilian Amazon State of Rondonia. We used chronosequences of forest and pasture of different ages to document patterns of labile, occluded, and organic P pools using a sequential P fractionation technique, Phosphorus released from the aboveground forest biomass substantially increased soil available P during the first 3 to 5 yr after forest clearing and burning. During this period, nonoccluded forms of inorganic P increased by 2.0 to 2.7-fold in the resin-extractable fraction and by 4 to 25-fold in the dilute HCl-extractable fraction. The introduction of grasses influenced the redistribution of soil P forms in older pastures. Occluded P comprised a low er proportion of total P (40-55%) in 20-yr-old pastures compared with forests (63-65%), but the proportion of organic P in these pastures increased (29-35%) compared with forests (20-21%). From the patterns in P transformations we developed a conceptual model in which we contrasted P transformations during slash and burn for pasture with changes to soil P that occur during soil formation. On cleared lands, the one-mag process by which P in primary minerals is converted to occluded and organic forms is reset by the cutting and burning of plant biomass, but instead of being released from primary minerals, P is released from the burned and decomposing biomass, Because this occurs in an already weathered soil, P transformation from nonoccluded to occluded and organic forms occurs in textless50 yr instead of the thousands of years required for these same transformations to occur during primary succession. | |||||
BibTeX:
@article{garcia-montiel_soil_2000, author = {Garcia-Montiel, D. C. and Neill, C. and Melillo, J. and Thomas, S. and Steudler, P. A. and Cerri, C. C.}, title = {Soil phosphorus transformations following forest clearing for pasture in the Brazilian Amazon}, journal = {Soil Science Society of America Journal}, year = {2000}, volume = {64}, number = {5}, pages = {1792--1804}, url = {://WOS:000089688600033} } |
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Garcia-Montiel, D.C., Melillo, J.M., Steudler, P.A., Tian, H., Neill, C., Kicklighter, D.W., Feigl, B., Piccolo, M. and Cerri, C.C. | Emissions of N2O and CO2 from terra firme forests in Rondonia, Brazil | 2004 | Ecological Applications Vol. 14(4), pp. S214-S220 |
article | URL |
Abstract: Nitrous oxide (N2O) functions as a greenhouse gas in the lower atmosphere and as a. destroyer of the ozone layer in the upper atmosphere. Tropical forest soils are considered the largest natural N2O source, but the spatial pattern of the emissions is poorly understood because of the relatively small number of ground measurements and the lack of a good way to scale them. In this paper, we present a new approach for estimating the magnitude and spatial pattern of N2O emissions from tropical forest soils of the Amazon Basin. First, we develop an empirical relationship between N2O and CO2 emissions from tropical soils based on seven years of field measurements made in forests of Rondonia, Brazil. Second, we combine this empirical relationship with monthly estimates of forest soil respiration across the basin from a process-based biogeochemistry model, the terrestrial ecosystem model, to estimate annual N2O fluxes and the spatial pattern of these fluxes from the region's undisturbed forests for the period 1980-1995. For this time interval, we estimate the average flux from the forest soils of the Amazon Basin was 7.9 X 10(11) g N2O-N/yr, with the highest subregional fluxes coming from the most productive forests in the northwestern part of the basin. | |||||
BibTeX:
@article{garcia-montiel_emissions_2004, author = {Garcia-Montiel, D. C. and Melillo, J. M. and Steudler, P. A. and Tian, H. and Neill, C. and Kicklighter, D. W. and Feigl, B. and Piccolo, M. and Cerri, C. C.}, title = {Emissions of N2O and CO2 from terra firme forests in Rondonia, Brazil}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S214--S220}, url = {://WOS:000223269000018} } |
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Garcia-Montiel, D.C., Melillo, J.M., Steudler, P.A., Neill, C., Feigl, B.J. and Cerri, C.C. | Relationship between N2O and CO2 emissions from the Amazon Basin | 2002 | Geophysical Research Letters Vol. 29(6) |
article | DOI URL |
Abstract: [1] Soils of tropical forests are the most important source of atmospheric N2O from natural ecosystems, but the extant flux estimates are based on a relatively small number of field measurements and simple extrapolation procedures. We present an empirical relationship between N2O and CO2 emissions from soils of Amazon tropical forest based on seven years of field measurements in Rondonia, Brazil. This relationship can be combined with estimates of soil CO2 emissions from existing biogeochemistry models to produce estimates of N2O emissions for tropical forest regions. | |||||
BibTeX:
@article{garcia-montiel_relationship_2002, author = {Garcia-Montiel, D. C. and Melillo, J. M. and Steudler, P. A. and Neill, C. and Feigl, B. J. and Cerri, C. C.}, title = {Relationship between N2O and CO2 emissions from the Amazon Basin}, journal = {Geophysical Research Letters}, year = {2002}, volume = {29}, number = {6}, url = {://WOS:000178886600007}, doi = {https://doi.org/10.1029/2001gl013830} } |
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Garcia-Montiel, D.C., Melillo, J.M., Steudler, P.A., Cerri, C.C. and Piccolo, M.C. | Carbon limitations to nitrous oxide emissions in a humid tropical forest of the Brazilian Amazon | 2003 | Biology and Fertility of Soils Vol. 38(5), pp. 267-272 |
article | DOI URL |
Abstract: The availability of labile organic C for microbial metabolic processes could be an important factor regulating N2O emissions from tropical soils. We explored the effects of labile C on the emissions of N2O from a forest soil in the State of Rondonia in the southwestern quadrant of the Brazilian Amazon. We measured emissions of N2O from a forest soil after amendments with solutions containing glucose, water only or NO3-. Addition of glucose to the forest soil resulted in very large increases in N2O emissions whereas the water only and NO3- additions did not. These results suggest a strong C limitation on N2O production in this forest soil in the southwestern Amazon. | |||||
BibTeX:
@article{garcia-montiel_carbon_2003, author = {Garcia-Montiel, D. C. and Melillo, J. M. and Steudler, P. A. and Cerri, C. C. and Piccolo, M. C.}, title = {Carbon limitations to nitrous oxide emissions in a humid tropical forest of the Brazilian Amazon}, journal = {Biology and Fertility of Soils}, year = {2003}, volume = {38}, number = {5}, pages = {267--272}, url = {://WOS:000186232000001 http://www.springerlink.com/content/5w77jh3r67a0kf4w/fulltext.pdf}, doi = {https://doi.org/10.1007/s00374-003-0637-y} } |
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Garcia-Montiel, D.C., Coe, M.T., Cruz, M.P., Ferreira, J.N., da Silva, E.M. and Davidson, E.A. | Estimating seasonal changes in volumetric soil water content at Landscape scales in a Savanna ecosystem using two-dimensional resistivity profiling | 2008 | Earth Interactions Vol. 12 |
article | DOI URL |
Abstract: Water distributed in deep soil reservoirs is an important factor determining the ecosystem structure of water-limited environments, such as the seasonal tropical savannas of South America. In this study a two-dimensional (2D) geoelectrical profiling technique was employed to estimate seasonal dynamics of soil water content to 10-m depth along transects of 275 m in savanna vegetation during the period between 2002 and 2006. Methods were developed to convert resistivity values along these 2D resistivity profiles into volumetric water content (VWC) by soil depth. The 2D resistivity profiles revealed the following soil and aquifer structure characterizing the underground environment: 0-4 m of permanently unsaturated and seasonally droughty soil, less severely dry unsaturated soil at about 4-7 m, nearly permanently saturated soil between 7 and 10 m, mostly impermeable saprolite interspaced with fresh bedrock of parent material at about 10-30 m, and a region of highly conductive water-saturated material at 30 m and below. Considerable spatial variation of these relative depths is clearly demonstrated along the transects. Temporal dynamics in VWC indicate that the active zone of water uptake is predominantly at 0-7 m, and follows the seasonal cycles of precipitation and evapotranspiration. Uptake from below 7 m may have been critical for a short period near the beginning of the rainy season, although the seasonal variations in VWC in the 7-10-m layer are relatively small and lag the surface water recharge for about 6 months. Calculations using a simple 1-box water balance model indicate that average total runoff was 15-25 mm month-1 in the wet season and about 6-9 mm month-1 in the dry season. Modeled ET was about 75-85 mm month-1 in the wet season and 20-25 mm month-1 in the dry season. Variation in basal area and tree density along one transect was positively correlated with VWC of the 0-3-m and 0-7-m soil depths, respectively, during the wettest months. These multitemporal measurements demonstrate that the along-transect spatial differences in soil moisture are quasi-permanent and influence vegetation structure at the scale of tens to hundreds of meters. | |||||
BibTeX:
@article{garcia-montiel_estimating_2008, author = {Garcia-Montiel, Diana C. and Coe, Michael T. and Cruz, Meyr P. and Ferreira, Joice N. and da Silva, Euzebio M. and Davidson, Eric A.}, title = {Estimating seasonal changes in volumetric soil water content at Landscape scales in a Savanna ecosystem using two-dimensional resistivity profiling}, journal = {Earth Interactions}, year = {2008}, volume = {12}, url = {://WOS:000254892600001}, doi = {https://doi.org/10.1175/2007ei238.1} } |
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Garcia, S.R., Kayano, M.T., Calheiros, A.J.P., Andreoli, R.V. and de Souza, R.A.F. | Moisture and heat budgets of the south American monsoon system: climatological aspects [BibTeX] |
2016 | Theoretical and Applied Climatology Vol. 125, pp. 3-4 |
article | |
BibTeX:
@article{garcia_moisture_2016, author = {Garcia, Sâmia R. and Kayano, Mary T. and Calheiros, Alan J. P. and Andreoli, Rita Valéria and de Souza, Rodrigo Augusto Ferreira}, title = {Moisture and heat budgets of the south American monsoon system: climatological aspects}, journal = {Theoretical and Applied Climatology}, year = {2016}, volume = {125}, pages = {3--4} } |
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Garcia, S., Jardine, K., Souza, V.F.d., Souza, R.A.F.d., Duvoisin Junior, S. and Gonçalves, J.F.d.C. | Reassimilation of Leaf Internal CO2 Contributes to Isoprene Emission in the Neotropical Species Inga edulis Mart | 2019 | Forests Vol. 10(6) |
article | DOI |
Abstract: Isoprene (C5H8) is a hydrocarbon gas emitted by many tree species and has been shown to protect photosynthesis under abiotic stress. Under optimal conditions for photosynthesis, textasciitilde70%–90% of carbon used for isoprene biosynthesis is produced from recently assimilated atmospheric CO2. While the contribution of alternative carbon sources that increase with leaf temperature and other stresses have been demonstrated, uncertainties remain regarding the biochemical source(s) of isoprene carbon. In this study, we investigated leaf isoprene emissions (Is) from neotropical species Inga edulis Mart. as a function of light and temperature under ambient (450 µmol m−2 s−1) and CO2-free (0 µmol m−2 s−1) atmosphere. Is under CO2-free atmosphere showed light-dependent emission patterns similar to those observed under ambient CO2, but with lower light saturation point. Leaves treated with the photosynthesis inhibitor DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) failed to produce detectable Is in normal light under a CO2-free atmosphere. While strong temperature-dependent Is were observed under CO2-free atmosphere in the light, dark conditions failed to produce detectable Is even at the highest temperatures studied (40 °C). Treatment of leaves with 13C-labeled sodium bicarbonate under CO2-free atmosphere resulted in Is with over 50% containing at least one 13C atom. Is under CO2-free atmosphere and standard conditions of light and leaf temperature represented 19% ± 7% of emissions under ambient CO2. The results show that the reassimilation of leaf internal CO2 contributes to Is in the neotropical species I. edulis. Through the consumption of excess photosynthetic energy, our results support a role of isoprene biosynthesis, together with photorespiration, as a key tolerance mechanism against high temperature and high light in the tropics. | |||||
BibTeX:
@article{garcia_reassimilation_2019, author = {Garcia, Sabrina and Jardine, Kolby and Souza, Vinicius F. de and Souza, Rodrigo A. F. de and Duvoisin Junior, Sergio and Gonçalves, José Francisco de C.}, title = {Reassimilation of Leaf Internal CO2 Contributes to Isoprene Emission in the Neotropical Species Inga edulis Mart}, journal = {Forests}, year = {2019}, volume = {10}, number = {6}, doi = {https://doi.org/10.3390/f10060472} } |
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Garcia, O.E., Diaz, A.M., Exposito, F.J., Diaz, J.P., Dubovik, O., Dubuisson, P., Roger, J.C., Eck, T.F., Sinyuk, A., Derimian, Y., Dutton, E.G., Schafer, J.S., Holben, B.N. and Garcia, C.A. | Validation of AERONET estimates of atmospheric solar fluxes and aerosol radiative forcing by ground-based broadband measurements | 2008 | Journal of Geophysical Research-Atmospheres Vol. 113(D21) |
article | DOI URL |
Abstract: The AErosol RObotic NETwork (AERONET) estimates of instantaneous solar broadband fluxes (F) at surface have been validated through comparison with ground-based measurements of broadband fluxes at Mauna Loa Observatory (MLO) and by the Baseline Surface Radiation (BSRN) and the Solar Radiation Networks (SolRad-Net) during the period 1999-2005 and 1999-2006, respectively. The uncertainties in the calculated aerosol radiative forcing (Delta F) and radiative forcing efficiency (Delta F(eff)) at the bottom of the atmosphere were also assessed. The stations have been selected attempting to cover different aerosols influences and hence radiative properties: urban-industrial, biomass burning, mineral dust, background continental, maritime aerosols and free troposphere. The AERONET solar downward fluxes at surface agree with ground-based measurements in all situations, with a correlation higher than 99% whereas the relation of observed to modeled fluxes ranges from 0.98 to 1.02. Globally an overestimation of 9 +/- 12 Wm(-2) of solar measurements was found, whereas for MLO (clear atmosphere) the differences decrease noticeably up to 2 +/- 10 Wm(-2). The highest dispersion between AERONET estimates and measurements was observed in locations dominated by mineral dust and mixed aerosols types. In these locations, the F and Delta F uncertainties have shown a modest increase of the differences for high aerosol load, contrary to Delta F(eff) which are strongly affected by low aerosol load. Overall the discrepancies clustered within 9 +/- 12 Wm(-2) for Delta F and 28 +/- 30 Wm(-2) per unit of aerosol optical depth, tau, at 0.55 mu m for Delta F(eff), where the latter is given for tau(0.44 mu m) textgreater= 0.4. The error distributions have not shown any significant tendency with other aerosol radiative properties as well as size and shape particles. | |||||
BibTeX:
@article{garcia_validation_2008, author = {Garcia, O. E. and Diaz, A. M. and Exposito, F. J. and Diaz, J. P. and Dubovik, O. and Dubuisson, P. and Roger, J. C. and Eck, T. F. and Sinyuk, A. and Derimian, Y. and Dutton, E. G. and Schafer, J. S. and Holben, B. N. and Garcia, C. A.}, title = {Validation of AERONET estimates of atmospheric solar fluxes and aerosol radiative forcing by ground-based broadband measurements}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2008}, volume = {113}, number = {D21}, url = {://WOS:000260992100003}, doi = {https://doi.org/10.1029/2008jd010211} } |
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Garcia, M.N., Ferreira, M.J., Ivanov, V., dos Santos, V.A.H.F., Ceron, J.V., Guedes, A.V., Saleska, S.R. and Oliveira, R.S. | Importance of hydraulic strategy trade-offs in structuring response of canopy trees to extreme drought in central Amazon | 2021 | Oecologia Vol. 197(1), pp. 13-24 |
article | DOI URL |
Abstract: Plant ecophysiological trade-offs between different strategies for tolerating stresses are widely theorized to shape forest functional diversity and vulnerability to climate change. However, trade-offs between hydraulic and stomatal regulation during natural droughts remain under-studied, especially in tropical forests. We investigated eleven mature forest canopy trees in central Amazonia during the strong 2015 El Niño. We found greater xylem embolism resistance ($$P\_50\$$= − 3.3 ± 0.8 MPa) and hydraulic safety margin (HSM = 2.12 ± 0.57 MPa) than previously observed in more precipitation-seasonal rainforests of eastern Amazonia and central America. We also discovered that taller trees exhibited lower embolism resistance and greater stomatal sensitivity, a height-structured trade-off between hydraulic resistance and active stomatal regulation. Such active regulation of tree water status, triggered by the onset of stem embolism, acted as a feedback to avoid further increases in embolism, and also explained declines in photosynthesis and transpiration. These results suggest that canopy trees exhibit a conservative hydraulic strategy to endure drought, with trade-offs between investment in xylem to reduce vulnerability to hydraulic failure, and active stomatal regulation to protect against low water potentials. These findings improve our understanding of strategies in tropical forest canopies and contribute to more accurate prediction of drought responses. | |||||
BibTeX:
@article{garcia_importance_2021, author = {Garcia, Maquelle Neves and Ferreira, Marciel José and Ivanov, Valeriy and dos Santos, Victor Alexandre Hardt Ferreira and Ceron, João Vitor and Guedes, Alacimar Viana and Saleska, Scott Reid and Oliveira, Rafael Silva}, title = {Importance of hydraulic strategy trade-offs in structuring response of canopy trees to extreme drought in central Amazon}, journal = {Oecologia}, year = {2021}, volume = {197}, number = {1}, pages = {13--24}, url = {https://doi.org/10.1007/s00442-021-04924-9}, doi = {https://doi.org/10.1007/s00442-021-04924-9} } |
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Gandu, A.W. and Dias, P.L.S. | Impact of tropical heat sources on the South American tropospheric upper circulation and subsidence | 1998 | Journal of Geophysical Research-Atmospheres Vol. 103(D6), pp. 6001-6015 |
article | DOI URL |
Abstract: The nonlinear adjustment of the wind and mass fields to idealized tropical heat sources is studied with a simple nonlinear primitive equation model with emphasis on the upper level circulation over South America and neighboring oceanic regions during the austral summer. Numerical experiments are performed with (1) an idealized symmetrical heat source in the Amazon region, (2) the asymmetry induced in source (1) by the SACZ, (3) the effect of the Atlantic ITCZ off the Amazon mouth, (4) the African heat source, (5) the West Pacific source, and (6) the central Pacific source during the warm phase of ENSO. The linear response is obtained through the reduction of the heat source by a factor of 10 and subsequent multiplication of the results by the same factor. Two basic questions are discussed: (1) are localized heat sources important for the development of the observed cyclonic flow in the midequatorial Atlantic and (2) where is the compensating subsidence associated with the Amazon heat source located? The nonlinearity helps organizing a weak cyclonic curvature in the midequatorial Atlantic, with the inclusion of source (2). The basic state generated by the west Pacific source, and primarily by the central Pacific source, has a large impact on the cyclonic curvature on the equatorial Atlantic. The compensating subsidence associated with the Amazon source is concentrated on the southwest side of the source. The SACZ extension helps to enhance the subsidence over the northern Argentina, and the Atlantic ITCZ enhances the subsidence over northeast Brazil and central equatorial Atlantic. Nonlinearity weakens the subsidence at the 500 hPa level inducing a more barotropic structure in the dynamical response to the heating. | |||||
BibTeX:
@article{gandu_impact_1998, author = {Gandu, A. W. and Dias, P. L. S.}, title = {Impact of tropical heat sources on the South American tropospheric upper circulation and subsidence}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1998}, volume = {103}, number = {D6}, pages = {6001--6015}, url = {://WOS:000072737800005}, doi = {https://doi.org/10.1029/97jd03114} } |
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Gandu, A.W., Cohen, J.C.P. and de Souza, J.R.S. | Simulation of deforestation in eastern Amazonia using a high-resolution model | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 123-135 |
article | DOI URL |
Abstract: This work evaluates the impact of deforestation on the climate of the eastern portion of the Amazon basin. This region is primarily an area of native tropical rainforest, but also contains several other natural ecosystems such as mangroves and savanna. It is the most densely populated area in Amazonia, and has been significantly affected by deforestation. In this study, numerical simulations were performed with a high spatial resolution, regional model that allows for consideration of mesoscale aspects such as topography, coastlines and large rivers. To evaluate the present situation and to predict potential future effects of deforestation on the climatic conditions of this region, two, one-year model simulations were made. In the first, "control simulation", an attempt was made to match the existing surface vegetation. The biophysical parameters used were derived from recent studies of similar Amazon-region ecosystems. In the second run, "deforested simulation", the forested-area biophysical parameters were replaced by those corresponding to the pasture areas of the region. The higher-resolution regional modelling revealed important climatic features of the deforestation process, displaying some associated mesoscale effects that are not typically represented in similar Global Circulation Model simulations. Near coastal zones and along large rivers, deforestation resulted in reduced cloud cover and precipitation. However, increased cloud cover and precipitation was predicted over upland areas, especially on slopes facing river valleys. The modelled surface sensible and latent heat fluxes also presented both positive and negative anomalies. The magnitudes of these anomalies were greater during the dry season. Windspeed near the surface was the meteorological variable that presented the most significant change due to deforestation. The reduction in roughness coefficient resulting from the shift from forest to pasture produced increased windspeeds near the Atlantic coast. The greater windspeeds diminished local humidity convergence and consequently reduced rainfall totals in nearby regions. The results obtained from these higher-resolution simulations show that, in general, orography, coastline profile and the distribution of large rivers play important roles in determining anomaly patterns of precipitation, wind, and energy exchange associated with deforestation in eastern Amazonia. | |||||
BibTeX:
@article{gandu_simulation_2004, author = {Gandu, A. W. and Cohen, J. C. P. and de Souza, J. R. S.}, title = {Simulation of deforestation in eastern Amazonia using a high-resolution model}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {123--135}, url = {://WOS:000222024700010}, doi = {https://doi.org/10.1007/s00704-004-0048-5} } |
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Galvao, L.S., Roberts, D.A., Formaggio, A.R., Numata, I. and Breunig, F.M. | View angle effects on the discrimination of soybean varieties and on the relationships between vegetation indices and yield using off-nadir Hyperion data | 2009 | Remote Sensing of Environment Vol. 113(4), pp. 846-856 |
article | DOI URL |
Abstract: Imaging spectrometry has the potential to provide improved discrimination of crop types and better estimates of crop yield. Here we investigate the potential of Hyperion to discriminate three Brazilian soybean varieties and to evaluate the relationship between grain yield and 17 narrow-band vegetation indices. Hyperion analysis focused on two datasets acquired from opposite off-nadir viewing directions but similar solar geometry: one acquired on 08 February 2005 (forward scattering) and the other on 14 January 2006 (back scattering). In 2005, the soybean canopies were observed by Hyperion at later reproductive stages than in 2006. Additional Hyperion datasets were not available due to cloud cover. To further examine the impact of viewing geometry within the same season, Hyperion data were complemented by 250 m Moderate Resolution Imaging Spectroradiometer (MODIS) images (bands I and 2) acquired in consecutive days (05-06 February 2005) with opposite viewing geometries (-42 degrees and +44 degrees, respectively). MODIS data analysis was used to keep reproductive stage as a constant factor while isolating the impact of viewing geometry. For discrimination purposes, multiple discriminant analysis (MDA) was applied over each dataset using surface reflectance values as input variables and a stepwise procedure for band selection. All possible Hyperion band ratios and the 17 narrow-band vegetation indices with soybean grain yield were evaluated across years through Pearson's correlation coefficients and linear regression. MODIS-derived Normalized Difference Vegetation Index (NDVI) and Simple Ratio (SR) were evaluated within the same growing season. Results showed that: (1) the three soybean varieties were discriminated with highest accuracy in the back scattering direction, as deduced from MDA classification results from Hyperion and MODIS data; (2) the highest correlation between Hyperion vegetation indices and soybean yield was observed for the Normalized Difference Water Index (NDWI) (r=+0.74) in the back scattering direction and this result was consistent with band ratio analysis: (3) higher Hyperion correlation results were observed in the back scattering direction when compared to the forward scattering image. For the same reproductive stage, stronger shadowing effects were observed over the MODIS red band in the forward scattering direction producing lower and lesser variable reflectance for the sensor. As a result, the relationship between MODIS-derived NDVI and soybean yield improved from the forward (r of +0.21) to the back scattering view (r of +0.60). The same trend was observed for SIR that increased from +0.22 to +0.58. (C) 2008 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{galvao_view_2009, author = {Galvao, Lenio Soares and Roberts, Dar A. and Formaggio, Antonio Roberto and Numata, Izaya and Breunig, Fabio Marcelo}, title = {View angle effects on the discrimination of soybean varieties and on the relationships between vegetation indices and yield using off-nadir Hyperion data}, journal = {Remote Sensing of Environment}, year = {2009}, volume = {113}, number = {4}, pages = {846--856}, url = {://WOS:000264503400013}, doi = {https://doi.org/10.1016/j.rse.2008.12.010} } |
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Galvão, J. and Fisch, G. | Balanço de energia em áreas de floresta e pastagem na Amazonia [BibTeX] |
2000 | Revista Brasileira de Meteorologia Vol. 15, pp. 25-38 |
article | |
BibTeX:
@article{galvao_balanco_2000, author = {Galvão, J.A.C. and Fisch, G.}, title = {Balanço de energia em áreas de floresta e pastagem na Amazonia}, journal = {Revista Brasileira de Meteorologia}, year = {2000}, volume = {15}, pages = {25--38} } |
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Gallon, S., Paulo, L. and M.M.P., S.R. | Fluxo e perfil de dióxido de carbono no dossel uma floresta tropical de transição amazônica [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 291-300 |
article | |
BibTeX:
@article{gallon_fluxo_2006, author = {Gallon, Sanches, L., Paulo, S.R., M.M.P.}, title = {Fluxo e perfil de dióxido de carbono no dossel uma floresta tropical de transição amazônica}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {291--300} } |
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Galford, G.L., Melillo, J., Mustard, J.F., Cerri, C.E.P. and Cerri, C.C. | The Amazon Frontier of Land-Use Change: Croplands and Consequences for Greenhouse Gas Emissions | 2010 | Earth Interactions Vol. 14 |
article | DOI URL |
Abstract: The Brazilian Amazon is one of the most rapidly developing agricultural frontiers in the world. The authors assess changes in cropland area and the intensification of cropping in the Brazilian agricultural frontier state of Mato Grosso using remote sensing and develop a greenhouse gas emissions budget. The most common type of intensification in this region is a shift from single-to double-cropping patterns and associated changes in management, including increased fertilization. Using the enhanced vegetation index (EVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, the authors created a green-leaf phenology for 2001-06 that was temporally smoothed with a wavelet filter. The wavelet-smoothed green-leaf phenology was analyzed to detect cropland areas and their cropping patterns. The authors document cropland extensification and double-cropping intensification validated with field data with 85% accuracy for detecting croplands and 64% and 89% accuracy for detecting single-and double-cropping patterns, respectively. The results show that croplands more than doubled from 2001 to 2006 to cover about 100 000 km(2) and that new double-cropping intensification occurred on over 20% of croplands. Variations are seen in the annual rates of extensification and double-cropping intensification. Greenhouse gas emissions are estimated for the period 2001-06 due to conversion of natural vegetation and pastures to row-crop agriculture in Mato Grosso averaged 179 Tg CO(2)-e yr(-1),over half the typical fossil fuel emissions for the country in recent years. | |||||
BibTeX:
@article{galford_amazon_2010, author = {Galford, Gillian L. and Melillo, Jerry and Mustard, John F. and Cerri, Carlos E. P. and Cerri, Carlos C.}, title = {The Amazon Frontier of Land-Use Change: Croplands and Consequences for Greenhouse Gas Emissions}, journal = {Earth Interactions}, year = {2010}, volume = {14}, url = {://WOS:000285720100001 http://journals.ametsoc.org/doi/abs/10.1175/2010EI327.1}, doi = {https://doi.org/10.1175/2010ei327.1} } |
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Galbraith, D., Malhi, Y., Aragão, L. and Baker, T. | The ecosystem dynamics of Amazonian and Andean forests [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 1-6 |
article | |
BibTeX:
@article{galbraith_ecosystem_2014, author = {Galbraith, David and Malhi, Yadvinder and Aragão, Luiz and Baker, Timothy}, title = {The ecosystem dynamics of Amazonian and Andean forests}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {1--6} } |
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Galbraith, D., Levy, P.E., Sitch, S., Huntingford, C., Cox, P., Williams, M. and Meir, P. | Multiple mechanisms of Amazonian forest biomass losses in three dynamic global vegetation models under climate change | 2010 | New Phytologist Vol. 187(3), pp. 647-665 |
article | DOI URL |
Abstract: PtextgreaterThe large-scale loss of Amazonian rainforest under some future climate scenarios has generally been considered to be driven by increased drying over Amazonia predicted by some general circulation models (GCMs). However, the importance of rainfall relative to other drivers has never been formally examined. Here, we conducted factorial simulations to ascertain the contributions of four environmental drivers (precipitation, temperature, humidity and CO(2)) to simulated changes in Amazonian vegetation carbon (C(veg)), in three dynamic global vegetation models (DGVMs) forced with climate data based on HadCM3 for four SRES scenarios. Increased temperature was found to be more important than precipitation reduction in causing losses of Amazonian C(veg) in two DGVMs (Hyland and TRIFFID), and as important as precipitation reduction in a third DGVM (LPJ). Increases in plant respiration, direct declines in photosynthesis and increases in vapour pressure deficit (VPD) all contributed to reduce C(veg) under high temperature, but the contribution of each mechanism varied greatly across models. Rising CO(2) mitigated much of the climate-driven biomass losses in the models. Additional work is required to constrain model behaviour with experimental data under conditions of high temperature and drought. Current models may be overly sensitive to long-term elevated temperatures as they do not account for physiological acclimation. | |||||
BibTeX:
@article{galbraith_multiple_2010, author = {Galbraith, David and Levy, Peter E. and Sitch, Stephen and Huntingford, Chris and Cox, Peter and Williams, Mathew and Meir, Patrick}, title = {Multiple mechanisms of Amazonian forest biomass losses in three dynamic global vegetation models under climate change}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {647--665}, note = {Edition: 2010/07/28}, url = {://WOS:000280122500011}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03350.x} } |
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Gagne-Maynard, W.C., Ward, N.D., Keil, R.G., Sawakuchi, H.O., da Cunha, A.C., Neu, V., Brito, D.C., Da Silva Less, D.F., Diniz, J.E.M., de Matos Valerio, A., Kampel, M., Krusche, A.V. and Richey, J.E. | Evaluation of Primary Production in the Lower Amazon River Based on a Dissolved Oxygen Stable Isotopic Mass Balance [BibTeX] |
2017 | Frontiers in Marine Science Vol. 4, pp. 1-12 |
article | |
BibTeX:
@article{gagne-maynard_evaluation_2017, author = {Gagne-Maynard, William C. and Ward, Nicholas D. and Keil, Richard G. and Sawakuchi, Henrique O. and da Cunha, Alan C. and Neu, Vania and Brito, Daimio C. and Da Silva Less, Diani F. and Diniz, Joel E. M. and de Matos Valerio, Aline and Kampel, Milton and Krusche, A. V. and Richey, Jeffrey E.}, title = {Evaluation of Primary Production in the Lower Amazon River Based on a Dissolved Oxygen Stable Isotopic Mass Balance}, journal = {Frontiers in Marine Science}, year = {2017}, volume = {4}, pages = {1--12} } |
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Fyllas, NM, Mercado, LM, Sitch, S, Quesada, CA, Domingues, TF, Galbraith, DR, Torre-Lezama, A, Vilanova, E, Ramírez-Angulo, H, Higuchi, N, Neill, DA, Silveira, M, Ferreira, L, Aymard, CGA, Malhi, Y, Phillips OL & Lloyd, J. and Gloor, E | Analysing Amazonian forest productivity using a new individual and trait-based model (TFS v.1). [BibTeX] |
2014 | Geoscientific Model Development Vol. 7(4), pp. 1251-1269 |
article | DOI |
BibTeX:
@article{fyllas_nm_analysing_2014, author = {Fyllas NM, Mercado LM, Sitch S, Quesada CA, Domingues TF, Galbraith DR, Torre-Lezama A, Vilanova E, Ramírez-Angulo H, Higuchi N, Neill DA, Silveira M, Ferreira L, Aymard CGA, Malhi Y, Phillips OL & Lloyd J., Gloor E}, title = {Analysing Amazonian forest productivity using a new individual and trait-based model (TFS v.1).}, journal = {Geoscientific Model Development}, year = {2014}, volume = {7}, number = {4}, pages = {1251--1269}, doi = {https://doi.org/10.5194/gmd-7-1251-2014} } |
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Fyllas, N., Quesada, C. and Lloyd, J. | Deriving Plant Functional Types for Amazonian forests for use in vegetation dynamics models [BibTeX] |
2012 | Perspectives in Plant Ecology, Evolution and Systematics Vol. 14, pp. 97-110 |
article | |
BibTeX:
@article{fyllas_deriving_2012, author = {Fyllas, N.M. and Quesada, C.A. and Lloyd, J.}, title = {Deriving Plant Functional Types for Amazonian forests for use in vegetation dynamics models}, journal = {Perspectives in Plant Ecology, Evolution and Systematics}, year = {2012}, volume = {14}, pages = {97--110} } |
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Fyllas, N.M., Patino, S., Baker, T.R., Nardoto, G.B., Martinelli, L.A., Quesada, C.A., Paiva, R., Schwarz, M., Horna, V., Mercado, L.M., Santos, A., Arroyo, L., Jimenez, E.M., Luizao, F.J., Neill, D.A., Silva, N., Prieto, A., Rudas, A., Silviera, M., Vieira, I.C.G., Lopez-Gonzalez, G., Malhi, Y., Phillips, O.L. and Lloyd, J. | Basin-wide variations in foliar properties of Amazonian forest: phylogeny, soils and climate | 2009 | Biogeosciences Vol. 6(11), pp. 2677-2708 |
article | DOI URL |
Abstract: We analysed 1040 individual trees, located in 62 plots across the Amazon Basin for leaf mass per unit area (M(A)), foliar carbon isotopic composition (delta(13)C) and leaf level concentrations of C, N, P, Ca, Mg, K and Al. All trees were identified to the species level with the dataset containing 58 families, 236 genera and 508 species, distributed across a wide range of soil types and precipitation regimes. Some foliar characteristics such as M(A), [C], [N] and [Mg] emerge as highly constrained by the taxonomic affiliation of tree species, but with others such as [P], [K], [Ca] and delta(13)C also strongly influenced by site growing conditions. By removing the environmental contribution to trait variation, we find that intrinsic values of most trait pairs coordinate, although different species ( characterised by different trait suites) are found at discrete locations along a common axis of coordination. Species that tend to occupy higher fertility soils are characterised by a lower M(A) and have a higher intrinsic [N], [P], [K], [Mg] and delta(13)C than their lower fertility counterparts. Despite this consistency, different scaling patterns were observed between low and high fertility sites. Inter-relationships are thus substantially modified by growth environment. Analysing the environmental component of trait variation, we found soil fertility to be the most important predictor, influencing all leaf nutrient concentrations and delta(13)C and reducing M(A). Mean annual temperature was negatively associated with leaf level [N], [P] and [K] concentrations. Total annual precipitation positively influences M(A), [C] and delta(13)C, but with a negative impact on [Mg]. These results provide a first basis for understanding the relationship between the physiological functioning and distribution of tree species across Amazonia. | |||||
BibTeX:
@article{fyllas_basin-wide_2009, author = {Fyllas, N. M. and Patino, S. and Baker, T. R. and Nardoto, G. Bielefeld and Martinelli, L. A. and Quesada, C. A. and Paiva, R. and Schwarz, M. and Horna, V. and Mercado, L. M. and Santos, A. and Arroyo, L. and Jimenez, E. M. and Luizao, F. J. and Neill, D. A. and Silva, N. and Prieto, A. and Rudas, A. and Silviera, M. and Vieira, I. C. G. and Lopez-Gonzalez, G. and Malhi, Y. and Phillips, O. L. and Lloyd, J.}, title = {Basin-wide variations in foliar properties of Amazonian forest: phylogeny, soils and climate}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {11}, pages = {2677--2708}, url = {://WOS:000272232200025 http://www.biogeosciences.net/6/2677/2009/bg-6-2677-2009.pdf}, doi = {https://doi.org/10.5194/bg-6-2677-2009} } |
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Fuzzi, S., Decesari, S., Facchini, M.C., Cavalli, F., Emblico, L., Mircea, M., Andreae, M.O., Trebs, I., Hoffer, A., Guyon, P., Artaxo, P., Rizzo, L.V., Lara, L.L., Pauliquevis, T., Maenhaut, W., Raes, N., Chi, X., Mayol-Bracero, O.L., Soto-Garcia, L.L., Claeys, M., Kourtchev, I., Rissler, J., Swietlicki, E., Tagliavini, E., Schkolnik, G., Falkovich, A.H., Rudich, Y., Fisch, G. and Gatti, L.V. | Overview of the inorganic and organic composition of size-segregated aerosol in Rondonia, Brazil, from the biomass-burning period to the onset of the wet season | 2007 | Journal of Geophysical Research-Atmospheres Vol. 112(D1) |
article | DOI URL |
Abstract: [1] The aerosol characterization experiment performed within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia-Smoke, Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) field experiment carried out in Rondonia, Brazil, in the period from September to November 2002 provides a unique data set of size-resolved chemical composition of boundary layer aerosol over the Amazon Basin from the intense biomass-burning period to the onset of the wet season. Three main periods were clearly distinguished on the basis of the PM(10) concentration trend during the experiment: (1) dry period, with average PM(10) well above 50 mu g m(-3); (2) transition period, during which the 24-hour-averaged PM(10) never exceeded 40 mu g m(-3) and never dropped below 10 mg m(-3); (3) and wet period, characterized by 48-hour-averaged concentrations of PM(10) below 12 mu g m(-3) and sometimes as low as 2 mu g m(-3). The trend of PM(10) reflects that of CO concentration and can be directly linked to the decreasing intensity of the biomass- burning activities from September through November, because of the progressive onset of the wet season. Two prominent aerosol modes, in the submicron and supermicron size ranges, were detected throughout the experiment. Dry period size distributions are dominated by the fine mode, while the fine and coarse modes show almost the same concentrations during the wet period. The supermicron fraction of the aerosol is composed mainly of primary particles of crustal or biological origin, whereas submicron particles are produced in high concentrations only during the biomass-burning periods and are mainly composed of organic material, mostly water-soluble, and similar to 10% of soluble inorganic salts, with sulphate as the major anion. Size-resolved average aerosol chemical compositions are reported for the dry, transition, and wet periods. However, significant variations in the aerosol composition and concentrations were observed within each period, which can be classified into two categories: (1) diurnal oscillations, caused by the diurnal cycle of the boundary layer and the different combustion phase active during day (flaming) or night (smouldering); and (2) day-to-day variations, due to alternating phases of relatively wet and dry conditions. In a second part of the study, three subperiods representative of the conditions occurring in the dry, transition, and wet periods were isolated to follow the evolution of the aerosol chemical composition as a function of changes in rainfall rate and in the strength of the sources of particulate matter. The chemical data set provided by the SMOCC field experiment will be useful to characterize the aerosol hygroscopic properties and the ability of the particles to act as cloud condensation nuclei. | |||||
BibTeX:
@article{fuzzi_overview_2007, author = {Fuzzi, Sandro and Decesari, Stefano and Facchini, Maria Cristina and Cavalli, Fabrizia and Emblico, Lorenza and Mircea, Mihaiela and Andreae, Meinrat O. and Trebs, Ivonne and Hoffer, Andras and Guyon, Pascal and Artaxo, Paulo and Rizzo, Luciana V. and Lara, Luciene L. and Pauliquevis, Theotonio and Maenhaut, Willy and Raes, Nico and Chi, Xuguang and Mayol-Bracero, Olga L. and Soto-Garcia, Lydia L. and Claeys, Magda and Kourtchev, Ivan and Rissler, Jenny and Swietlicki, Erik and Tagliavini, Emilio and Schkolnik, Gal and Falkovich, Alla H. and Rudich, Yinon and Fisch, Gilberto and Gatti, Luciana V.}, title = {Overview of the inorganic and organic composition of size-segregated aerosol in Rondonia, Brazil, from the biomass-burning period to the onset of the wet season}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2007}, volume = {112}, number = {D1}, url = {://WOS:000243352300002}, doi = {https://doi.org/10.1029/2005jd006741} } |
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Futemma, C., De Castro, F., Silva-Forsberg, M.C. and Ostrom, E. | The emergence and outcomes of collective action: An institutional and ecosystem approach | 2002 | Society & Natural Resources Vol. 15(6), pp. 503-522 |
article | DOI URL |
Abstract: Participation in collective action is frequently studied through a community-based analysis, with focus on the social features of the participants and on the ecological features of the managed system. This study addresses the importance of scaling down to household level to understand different individual incentives to collaborate (or not) as well as scaling up to the landscape level to evaluate the ecological outcome of the local forms of collective action. We report on a study of a riparian community of 33 households in the Lower Amazon located between two distinct ecosystems-a privately owned upland forest and a communally owned floodplain. Household-based analysis uncovers how heterogeneity within the community leads to different incentives for participation in the communal floodplain, while systemic analysis reveals that interconnection between the managed ecosystem and adjacent ecosystem influences the decisions to participate as well as the ecological outcomes of the collective actions. | |||||
BibTeX:
@article{futemma_emergence_2002, author = {Futemma, C. and De Castro, F. and Silva-Forsberg, M. C. and Ostrom, E.}, title = {The emergence and outcomes of collective action: An institutional and ecosystem approach}, journal = {Society & Natural Resources}, year = {2002}, volume = {15}, number = {6}, pages = {503--522}, url = {://WOS:000176493200003}, doi = {https://doi.org/10.1080/08941920290069146} } |
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Futemma, C. and Brondizio, E.S. | Land reform and land-use changes in the lower amazon: Implications for agricultural intensification | 2003 | Human Ecology Vol. 31(3), pp. 369-402 |
article | DOI URL |
Abstract: Land tenure has been considered one of the key factors that define patterns and change in land-use systems. This paper examines the implications of land reform for household decisions regarding patterns of land use, agricultural intensification, and forest conservation. We look at an Amazonian caboclo settlement in the Lower Amazon that had experienced land reform by the end of the 1980s. Results show that defined land tenure is not enough to guarantee agricultural intensification and forest conservation. In fact, several factors working at different scales are affecting land-use change in the region. At the settlement level, privatization of upland forest has led to an overall increase in cultivated land - pasture and annual crops - and increasing deforestation rates. However, at the farm-property level, different systems of agricultural production - intensive, extensive, or abandonment of land - occur according to availability of labor, and capital, and access to different natural resources. | |||||
BibTeX:
@article{futemma_land_2003, author = {Futemma, C. and Brondizio, E. S.}, title = {Land reform and land-use changes in the lower amazon: Implications for agricultural intensification}, journal = {Human Ecology}, year = {2003}, volume = {31}, number = {3}, pages = {369--402}, url = {://WOS:000184588200002}, doi = {https://doi.org/10.1023/a:1025067721480} } |
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Furtado Neto, A.T., Junior, M., Tapajós, R., Dill, T., Valente, F., Cosme, R., Moura, J.M.S., Silva, H.C.P., Silva, R.d., Keller, M. and Crill, P. | Influência da umidade no efluxo de CO2 do solo para atmosfera em uma área de floresta primária, Belterra, PA [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 25 - 27 |
article | |
BibTeX:
@article{furtado_neto_influencia_2013, author = {Furtado Neto, Alírio T. and Junior, Miércio and Tapajós, Raphael and Dill, Thaís and Valente, Fabiola and Cosme, Raimundo and Moura, José Mauro S. and Silva, Hudson C. P. and Silva, Rodrigo da and Keller, Michael and Crill, Patrick}, title = {Influência da umidade no efluxo de CO2 do solo para atmosfera em uma área de floresta primária, Belterra, PA}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {25 -- 27} } |
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Fuentes, J.D., Gerken, T., Chamecki, M., Stoy, P., Freire, L. and Ruiz-Plancarte, J. | Turbulent transport and reactions of plant-emitted hydrocarbons in an Amazonian rain forest | 2022 | Atmospheric Environment Vol. 279, pp. 119094 |
article | DOI URL |
Abstract: The processes governing the temporal and spatial patterns of isoprene and monoterpenes emitted by a rainforest in the central Amazon region of Brazil is investigated using a combination of field experiments and numerical simulations. Specifically, Large Eddy Simulations (LES) were used to resolve emissions of isoprene and monoterpenes, turbulent transport, and air chemistry. The coupled chemistry-transport LES included the effects of isoprene and monoterpenes reactivity due to reactions with hydroxyl radical and ozone. The LES results are used to compute vertically resolved budgets of isoprene and monoterpenes in the rainforest canopy in response to emissions, turbulent transport, surface deposition, and air chemistry. Results indicated that emission and dispersion dominated the isoprene budget as the gases were transported out of the canopy space. In a region limited by nitrogen oxides (with prevailing nitric oxide levels of textless 0.5 parts per billion), the in-canopy chemical destruction removed approximately 10% of locally emitted monoterpenes. Hydroxyl radical production rates from the ozonolysis of monoterpenes amounted to ≈2×106radicalscm−3s−1 and had similar magnitude to the light-dependent hydroxyl radical formation. One key conclusion was that the Amazonia rainforest abundantly emitted monoterpenes whose in-canopy ozonolysis yielded hydroxyl radicals in amounts similar to the magnitude of light-dependent formation. Reactions of monoterpenes and isoprene with hydroxyl radical and ozone were necessary for the maintenance of the Amazon rainforest canopy as a photochemically active environment suitable to generate oxidants and secondary organic aerosols. | |||||
BibTeX:
@article{fuentes_turbulent_2022, author = {Fuentes, Jose D. and Gerken, Tobias and Chamecki, Marcelo and Stoy, Paul and Freire, Livia and Ruiz-Plancarte, Jesus}, title = {Turbulent transport and reactions of plant-emitted hydrocarbons in an Amazonian rain forest}, journal = {Atmospheric Environment}, year = {2022}, volume = {279}, pages = {119094}, url = {https://www.sciencedirect.com/science/article/pii/S1352231022001595}, doi = {https://doi.org/10.1016/j.atmosenv.2022.119094} } |
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Fuentes M. Chamecki, R.N.d.S.C.V.R.P.S.G.K.D.F.A.M.T.G.A.T.L.S.F.J.J. and Ruiz-Plancarte J. Tóta, N.D.G.F.C.S.O.A.and.J.M.J.F.M. | Linking meteorology, turbulence, and air chemistry in the Amazon rainforest [BibTeX] |
2016 | Bulletin of the American Meteorological Society Vol. 98, pp. BAMS-D-15-00152 |
article | DOI |
BibTeX:
@article{fuentes_linking_2016, author = {Fuentes, M. Chamecki, R. Nascimento dos Santos, C. Von Randow, P. Stoy, G. Katul, D. Fitzjarrald, A. Manzi, T. Gerken, A. Trowbridge, L. Souza Freire, J., J. and Ruiz-Plancarte, J. Tóta, N. Dias, G. Fisch, C. Schumacher, O. Acevedo, and J. Mercer, J. Furtunato Maia}, title = {Linking meteorology, turbulence, and air chemistry in the Amazon rainforest}, journal = {Bulletin of the American Meteorological Society}, year = {2016}, volume = {98}, pages = {BAMS--D--15--00152}, doi = {https://doi.org/10.1175/BAMS-D-15-00152.1} } |
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Fu, R. and Li, W. | The influence of the land surface on the transition from dry to wet season in Amazonia | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 97-110 |
article | DOI URL |
Abstract: Analysis of the fifteen years of European Centre for Medium Range Weather Forecasts (ECMWF) reanalysis suggests that the transition from dry to wet season in Southern Amazonia is initially driven by increases of surface latent heat flux. These fluxes rapidly reduce Convective Inhibition Energy (CINE) and increase Convective Available Potential Energy (CAPE), consequently providing favourable conditions for increased rainfall even before the large-scale circulation has changed. The increase of rainfall presumably initiates the reversal of the cross-equatorial flow, leading to large-scale net moisture convergence over Southern Amazonia. An analysis of early and late wet season onsets on an interannual scale shows that a longer dry season with lower rainfall reduces surface latent heat flux in the dry and earlier transition periods compared to that of a normal wet season onset. These conditions result in a higher CINE and a lower CAPE, causing a delay in the increase of local rainfall in the initiating phase of the transition and consequently in the wet season onset. Conversely, a wetter dry season leads to a higher surface latent heat flux and weaker CINE, providing a necessary condition for an earlier increase of local rainfall and an earlier wet season onset. Our results imply that if land use change in Amazonia reduces rainfall during dry and transition seasons, it could significantly delay the wet season onset and prolong the dry season. | |||||
BibTeX:
@article{fu_influence_2004, author = {Fu, R. and Li, W.}, title = {The influence of the land surface on the transition from dry to wet season in Amazonia}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {97--110}, url = {://WOS:000222024700008}, doi = {https://doi.org/10.1007/s00704-004-0046-7} } |
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Frolking, S., Palace, M.W., Clark, D.B., Chambers, J.Q., Shugart, H.H. and Hurtt, G.C. | Forest disturbance and recovery: A general review in the context of spaceborne remote sensing of impacts on aboveground biomass and canopy structure | 2009 | Journal of Geophysical Research-Biogeosciences Vol. 114 |
article | DOI URL |
Abstract: Abrupt forest disturbances generating gaps textgreater0.001 km(2) impact roughly 0.4-0.7 million km(2) a(-1). Fire, windstorms, logging, and shifting cultivation are dominant disturbances; minor contributors are land conversion, flooding, landslides, and avalanches. All can have substantial impacts on canopy biomass and structure. Quantifying disturbance location, extent, severity, and the fate of disturbed biomass will improve carbon budget estimates and lead to better initialization, parameterization, and/or testing of forest carbon c ycle models. Spaceborne remote sensing maps large-scale forest disturbance occurrence, location, and extent, particularly with moderate- and fine-scale resolution passive optical/near-infrared (NIR) instruments. High-resolution remote sensing (e. g., similar to 1 m passive optical/NIR, or small footprint lidar) can map crown geometry and gaps, but has rarely been systematically applied to study small-scale disturbance and natural mortality gap dynamics over large regions. Reducing uncertainty in disturbance and recovery impacts on global forest carbon balance requires quantification of (1) predisturbance forest biomass; (2) disturbance impact on standing biomass and its fate; and (3) rate of biomass accumulation during recovery. Active remote sensing data (e. g., lidar, radar) are more directly indicative of canopy biomass and many structural properties than passive instrument data; a new generation of instruments designed to generate global coverage/sampling of canopy biomass and structure can improve our ability to quantify the carbon balance of Earth's forests. Generating a high-quality quantitative assessment of disturbance impacts on canopy biomass and structure with spaceborne remote sensing requires comprehensive, well designed, and well coordinated field programs collecting high-quality ground-based data and linkages to dynamical models that can use this information. | |||||
BibTeX:
@article{frolking_forest_2009, author = {Frolking, S. and Palace, M. W. and Clark, D. B. and Chambers, J. Q. and Shugart, H. H. and Hurtt, G. C.}, title = {Forest disturbance and recovery: A general review in the context of spaceborne remote sensing of impacts on aboveground biomass and canopy structure}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2009}, volume = {114}, url = {://WOS:000268352400002}, doi = {https://doi.org/10.1029/2008jg000911} } |
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Frolking, S., Milliman, T., Palace, M., Wisser, D., Lammers, R. and Fahnestock, M. | Tropical forest backscatter anomaly evident in Sea Winds scatterometer morning overpass data during 2005 drought in Amazonia | 2011 | Remote Sensing of Environment Vol. 115(3), pp. 897-907 |
article | DOI URL |
Abstract: A severe drought occurred in southwestern Amazonia in the dry season (June-September) of 2005. We analyzed 10 years (7/99-10/09) of SeaWinds active microwave Ku-band backscatter data collected over the Amazon Basin, developing monthly means and anomalies from those means in an effort to detect landscape responses to this drought. We compared these to seasonal accumulating water deficit anomalies generated using Tropical Rainfall Monitoring Mission (TRMM) precipitation data (1999-2009) and 100 mm mo(-1) evapotranspiration demand as a water deficit threshold. There was significant interannual variability in dry-season monthly mean backscatter only for morning (c. 06:00 LST) overpass data, and little interannual variability in dry-season monthly mean backscatter for afternoon (c. 18:00 LST) overpass data. Strong negative anomalies in both morning-overpass backscatter and accumulating water deficit developed during July-October 2005, centered on the southwestern Amazon Basin, with a strong spatial correlation between morning-overpass backscatter anomalies and water deficit anomalies in September. This is the first reporting of tropical forest seasonal drought detection by active microwave scatterometry. Based on the differences between early-morning and late-afternoon backscatter variability, we hypothesize that as the drought persisted over several months, the forest canopy was increasingly unable to recover full leaf moisture content over night, resulting in anomalously low early-morning overpass backscatter. (C) 2010 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{frolking_tropical_2011, author = {Frolking, Steve and Milliman, Tom and Palace, Michael and Wisser, Dominik and Lammers, Richard and Fahnestock, Mark}, title = {Tropical forest backscatter anomaly evident in Sea Winds scatterometer morning overpass data during 2005 drought in Amazonia}, journal = {Remote Sensing of Environment}, year = {2011}, volume = {115}, number = {3}, pages = {897--907}, url = {://WOS:000287067400009}, doi = {https://doi.org/10.1016/j.rse.2010.11.017} } |
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Frohlich-Nowoisky, J., Burrows, S.M., Xie, Z., Engling, G., Solomon, P.A., Fraser, M.P., Mayol-Bracero, O.L., Artaxo, P., Begerow, D., Conrad, R., Andreae, M.O., Despres, V.R. and Poschl, U. | Biogeography in the air: fungal diversity over land and oceans [BibTeX] |
2012 | Biogeosciences Vol. 9, pp. 1125-1136 |
article | DOI |
BibTeX:
@article{frohlich-nowoisky_biogeography_2012, author = {Frohlich-Nowoisky, J. and Burrows, S. M. and Xie, Z. and Engling, G. and Solomon, P. A. and Fraser, M. P. and Mayol-Bracero, O. L. and Artaxo, P. and Begerow, D. and Conrad, R. and Andreae, M. O. and Despres, V. R. and Poschl, U.}, title = {Biogeography in the air: fungal diversity over land and oceans}, journal = {Biogeosciences}, year = {2012}, volume = {9}, pages = {1125--1136}, doi = {https://doi.org/10.5194/bgd-8-7071-2011} } |
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Frizano, J., Vann, D.R., Johnson, A.H., Johnson, C.M., Vieira, I.C.G. and Zarin, D.J. | Labile phosphorus in soils of forest fallows and primary forest in the Bragantina region, Brazil | 2003 | Biotropica Vol. 35(1), pp. 2-11 |
article | DOI URL |
Abstract: We used the Hedley sequential extraction procedure to measure nine different organic and inorganic soil phosphorus fractions in forest soils of the Bragantina region of Para, Brazil. We compared the labile fractions (resin-extractable P + HCO3-extractable inorganic and organic P) in Oxisols from three secondary forests (10, 20, and 40 years old) and a primary forest. These stands were located in an area that has supported shifting agriculture for approximately a century After agricultural use, total P and labile P in soils of young secondary forests are diminished compared to the amounts present in the primary forest soil. Within each stand, organic carbon content was a good predictor of labile organic and inorganic P, consistent with the large body of research indicating that mineralization of organic matter is important to plant nutrition in tropical ecosystems. During the reorganization of P pools during forest development, the pool of labile organic P (HCO3-extractable) diminishes more than the other labile fractions, suggesting that it is directly or indirectly an important source of P for the regrowing forest vegetation. Across the four age classes of forest, the soil reservoir of labile P was equal to or greater than the total amount of P in the vegetation. If labile P measured by this method adequately represents P available to plants in the short term (as suggested by the current consensus), we would conclude that plant-available P is reasonably abundant, and that the effects of agriculture on available P pools are detectable but not sufficient to compromise forest regrowth in this area. | |||||
BibTeX:
@article{frizano_labile_2003, author = {Frizano, J. and Vann, D. R. and Johnson, A. H. and Johnson, C. M. and Vieira, I. C. G. and Zarin, D. J.}, title = {Labile phosphorus in soils of forest fallows and primary forest in the Bragantina region, Brazil}, journal = {Biotropica}, year = {2003}, volume = {35}, number = {1}, pages = {2--11}, url = {://WOS:000182530700001}, doi = {https://doi.org/10.1646/0006-3606(2003)035%5B0002:lpisof%5D2.0.co;2} } |
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Freud, E., Rosenfeld, D., Andreae, M.O., Costa, A.A. and Artaxo, P. | Robust relations between CCN and the vertical evolution of cloud drop size distribution in deep convective clouds | 2008 | Atmospheric Chemistry and Physics Vol. 8(6), pp. 1661-1675 |
article | URL |
Abstract: In-situ measurements in convective clouds (up to the freezing level) over the Amazon basin show that smoke from deforestation fires prevents clouds from precipitating until they acquire a vertical development of at least 4 km, compared to only 1-2 km in clean clouds. The average cloud depth required for the onset of warm rain increased by similar to 350 m for each additional 100 cloud condensation nuclei per cm(3) at a super-saturation of 0.5% (CCN0.5%). In polluted clouds, the diameter of modal liquid water content grows much slower with cloud depth (at least by a factor of similar to 2), due to the large number of droplets that compete for available water and to the suppressed coalescence processes. Contrary to what other studies have suggested, we did not observe this effect to reach saturation at 3000 or more accumulation mode particles per cm(3). The CCN0.5% concentration was found to be a very good predictor for the cloud depth required for the onset of warm precipitation and other microphysical factors, leaving only a secondary role for the updraft velocities in determining the cloud drop size distributions. The effective radius of the cloud droplets (r(e)) was found to be a quite robust parameter for a given environment and cloud depth, showing only a small effect of partial droplet evaporation from the cloud's mixing with its drier environment. This supports one of the basic assumptions of satellite analysis of cloud microphysical processes: the ability to look at different cloud top heights in the same region and regard their r(e) as if they had been measured inside one well developed cloud. The dependence of r(e) on the adiabatic fraction decreased higher in the clouds, especially for cleaner conditions, and disappeared at r(e)textgreater=similar to 10 mu m. We propose that droplet coalescence, which is at its peak when warm rain is formed in the cloud at r(e)=similar to 10 mu m, continues to be significant during the cloud's mixing with the entrained air, cancelling out the decrease in r(e) due to evaporation. | |||||
BibTeX:
@article{freud_robust_2008, author = {Freud, E. and Rosenfeld, D. and Andreae, M. O. and Costa, A. A. and Artaxo, P.}, title = {Robust relations between CCN and the vertical evolution of cloud drop size distribution in deep convective clouds}, journal = {Atmospheric Chemistry and Physics}, year = {2008}, volume = {8}, number = {6}, pages = {1661--1675}, url = {://WOS:000254416700014} } |
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Freitas, S.R., Longo, K.M., Trentmann, J. and Latham, D. | Technical Note: Sensitivity of 1-D smoke plume rise models to the inclusion of environmental wind drag | 2010 | Atmospheric Chemistry and Physics Vol. 10(2), pp. 585-594 |
article | URL |
Abstract: Vegetation fires emit hot gases and particles which are rapidly transported upward by the positive buoyancy generated by the combustion process. In general, the final vertical height that the smoke plumes reach is controlled by the thermodynamic stability of the atmospheric environment and the surface heat flux released by the fire. However, the presence of a strong horizontal wind can enhance the lateral entrainment and induce additional drag, particularly for small fires, impacting the smoke injection height. In this paper, we revisit the parameterization of the vertical transport of hot gases and particles emitted from vegetation fires, described in Freitas et al. (2007), to include the effects of environmental wind on transport and dilution of the smoke plume at its scale. This process is quantitatively represented by introducing an additional entrainment term to account for organized inflow of a mass of cooler and drier ambient air into the plume and its drag by momentum transfer. An extended set of equations including the horizontal motion of the plume and the additional increase of the plume radius is solved to simulate the time evolution of the plume rise and the smoke injection height. One-dimensional (1-D) model results are presented for two deforestation fires in the Amazon basin with sizes of 10 and 50 ha under calm and windy atmospheric environments. The results are compared to corresponding simulations generated by the complex non-hydrostatic three-dimensional (3-D) Active Tracer High resolution Atmospheric Model (ATHAM). We show that the 1-D model results compare well with the full 3-D simulations. The 1-D model may thus be used in field situations where extensive computing facilities are not available, especially under conditions for which several optional cases must be studied. | |||||
BibTeX:
@article{freitas_technical_2010, author = {Freitas, S. R. and Longo, K. M. and Trentmann, J. and Latham, D.}, title = {Technical Note: Sensitivity of 1-D smoke plume rise models to the inclusion of environmental wind drag}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {2}, pages = {585--594}, url = {://WOS:000273954200019} } |
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Freitas, S.R., Longo, K.M., Diasb, M., Diasb, P.L.S., Chatfield, R., Prins, E., Artaxo, P., Grell, G.A. and Recuero, F.S. | Monitoring the transport of biomass burning emissions in South America | 2005 | Environmental Fluid Mechanics Vol. 5(1-2), pp. 135-167 |
article | DOI URL |
Abstract: The atmospheric transport of biomass burning emissions in the South American and African continents is being monitored annually using a numerical simulation of air mass motions; we use a tracer transport capability developed within RAMS (Regional Atmospheric Modeling System) coupled to an emission model. Mass conservation equations are solved for carbon monoxide (CO) and particulate material (PM2.5). Source emissions of trace gases and particles associated with biomass burning activities in tropical forest, savanna and pasture have been parameterized and introduced into the model. The sources are distributed spatially and temporally and assimilated daily using the biomass burning locations detected by remote sensing. Advection effects (at grid scale) and turbulent transport (at sub-grid scale) are provided by the RAMS parameterizations. A sub-grid transport parameterization associated with moist deep and shallow convection, not explicitly resolved by the model due to its low spatial resolution, has also been introduced. Sinks associated with the process of wet and dry removal of aerosol particles and chemical transformation of gases are parameterized and introduced in the mass conservation equation. An operational system has been implemented which produces daily 48-h numerical simulations (including 24-h forecasts) of CO and PM2.5, in addition to traditional meteorological fields. The good prediction skills of the model are demonstrated by comparisons with time series of PM2.5 measured at the surface. | |||||
BibTeX:
@article{freitas_monitoring_2005, author = {Freitas, S. R. and Longo, K. M. and Diasb, Mafs and Diasb, P. L. S. and Chatfield, R. and Prins, E. and Artaxo, P. and Grell, G. A. and Recuero, F. S.}, title = {Monitoring the transport of biomass burning emissions in South America}, journal = {Environmental Fluid Mechanics}, year = {2005}, volume = {5}, number = {1-2}, pages = {135--167}, url = {://WOS:000229939700006}, doi = {https://doi.org/10.1007/s10652-005-0243-7} } |
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Freitas, S.R., Longo, K.M., Dias, M.A.F.S., Chatfield, R., Dias, P.S., Artaxo, P., Andreae, M.O., Grell, G., Rodrigues, L.F., Fazenda, A. and Panetta, J. | The Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) - Part 1: Model description and evaluation | 2009 | Atmospheric Chemistry and Physics Vol. 9(8), pp. 2843-2861 |
article | URL |
Abstract: We introduce the Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS). CATT-BRAMS is an on-line transport model fully consistent with the simulated atmospheric dynamics. Emission sources from biomass burning and urban-industrial-vehicular activities for trace gases and from biomass burning aerosol particles are obtained from several published datasets and remote sensing information. The tracer and aerosol mass concentration prognostics include the effects of sub-grid scale turbulence in the planetary boundary layer, convective transport by shallow and deep moist convection, wet and dry deposition, and plume rise associated with vegetation fires in addition to the grid scale transport. The radiation parameterization takes into account the interaction between the simulated biomass burning aerosol particles and short and long wave radiation. The atmospheric model BRAMS is based on the Regional Atmospheric Modeling System (RAMS), with several improvements associated with cumulus convection representation, soil moisture initialization and surface scheme tuned for the tropics, among others. In this paper the CATT-BRAMS model is used to simulate carbon monoxide and particulate material (PM(2.5)) surface fluxes and atmospheric transport during the 2002 LBA field campaigns, conducted during the transition from the dry to wet season in the southwest Amazon Basin. Model evaluation is addressed with comparisons between model results and near surface, radiosondes and airborne measurements performed during the field campaign, as well as remote sensing derived products. We show the matching of emissions strengths to observed carbon monoxide in the LBA campaign. A relatively good comparison to the MOPITT data, in spite of the fact that MOPITT a priori assumptions imply several difficulties, is also obtained. | |||||
BibTeX:
@article{freitas_coupled_2009, author = {Freitas, S. R. and Longo, K. M. and Dias, M. A. F. Silva and Chatfield, R. and Dias, P. Silva and Artaxo, P. and Andreae, M. O. and Grell, G. and Rodrigues, L. F. and Fazenda, A. and Panetta, J.}, title = {The Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) - Part 1: Model description and evaluation}, journal = {Atmospheric Chemistry and Physics}, year = {2009}, volume = {9}, number = {8}, pages = {2843--2861}, url = {://WOS:000265743100015} } |
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Freitas, S.R., Longo, K.M., Chatfield, R., Latham, D., Silva Dias, M.A.F., Andreae, M.O., Prins, E., Santos, J.C., Gielow, R. and Carvalho Jr., J.A. | Including the sub-grid scale plume rise of vegetation fires in low resolution atmospheric transport models | 2007 | Atmospheric Chemistry and Physics Vol. 7(13), pp. 3385-3398 |
article | URL |
Abstract: We describe and begin to evaluate a parameterization to include the vertical transport of hot gases and particles emitted from biomass burning in low resolution atmospheric-chemistry transport models. This sub-grid transport mechanism is simulated by embedding a 1-D cloud-resolving model with appropriate lower boundary conditions in each column of the 3-D host model. Through assimilation of remote sensing fire products, we recognize which columns have fires. Using a land use dataset appropriate fire properties are selected. The host model provides the environmental conditions, allowing the plume rise to be simulated explicitly. The derived height of the plume is then used in the source emission field of the host model to determine the effective injection height, releasing the material emitted during the flaming phase at this height. Model results are compared with CO aircraft profiles from an Amazon basin field campaign and with satellite data, showing the huge impact that this mechanism has on model performance. We also show the relative role of each main vertical transport mechanisms, shallow and deep moist convection and the pyro-convection (dry or moist) induced by vegetation fires, on the distribution of biomass burning CO emissions in the troposphere. | |||||
BibTeX:
@article{freitas_including_2007, author = {Freitas, S. R. and Longo, K. M. and Chatfield, R. and Latham, D. and Silva Dias, M. A. F. and Andreae, M. O. and Prins, E. and Santos, J. C. and Gielow, R. and Carvalho, Jr., J. A.}, title = {Including the sub-grid scale plume rise of vegetation fires in low resolution atmospheric transport models}, journal = {Atmospheric Chemistry and Physics}, year = {2007}, volume = {7}, number = {13}, pages = {3385--3398}, url = {://WOS:000248733000001} } |
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Freitas, S.R., Longo, K.M. and Andreae, M.O. | Impact of including the plume rise of vegetation fires in numerical simulations of associated atmospheric pollutants | 2006 | Geophysical Research Letters Vol. 33(17) |
article | DOI URL |
Abstract: We investigate the importance of including in low-resolution atmospheric models the plume rise associated with the strong buoyancy of hot gases from vegetation fires. This sub-grid transport mechanism is simulated by embedding a 1D cloud resolving model, with appropriate lower boundary conditions, in each column of a 3D host model. Remote-sensing fire products are used in combination with a land use dataset for selection of appropriate fire properties. The host model provides the environmental conditions, and the plume rise is simulated explicitly. The final height of the plume is then used in the source emission field of the host model to determine the effective injection height, and the material emitted during the flaming phase is released at this height. Model results are compared with 500 hPa AIRS carbon monoxide ( CO) data for September 2002 and with CO aircraft profiles from the SMOCC campaign, showing the huge impact on model performance. | |||||
BibTeX:
@article{freitas_impact_2006, author = {Freitas, S. R. and Longo, K. M. and Andreae, M. O.}, title = {Impact of including the plume rise of vegetation fires in numerical simulations of associated atmospheric pollutants}, journal = {Geophysical Research Letters}, year = {2006}, volume = {33}, number = {17}, url = {://WOS:000240417400002}, doi = {https://doi.org/10.1029/2006gl026608} } |
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Freitas, S.R., Dias, M., Dias, P.L.S., Longo, K.M., Artaxo, P., Andreae, M.O. and Fischer, H. | A convective kinematic trajectory technique for low-resolution atmospheric models | 2000 | Journal of Geophysical Research-Atmospheres Vol. 105(D19), pp. 24375-24386 |
article | DOI URL |
Abstract: This paper presents a simple methodology to take into account the subgrid effects of wet convective processes to trace vertical motion of air parcels for low-resolution atmospheric models. Such models are used for wind field simulations that serve as input for trajectory models. Air parcels in moist convective regions can thus be vertically transported to the cumulus top level with the short timescale associated with cumulus updrafts. Two cases are presented: wet and dry seasons in Amazonia, showing the differences of trajectories followed by air parcels with and without the methodology. The implications for the interpretation of air chemistry measurements are discussed, and an example using LBA/CLAIRE data is used to point out the usefulness of the convective kinematic trajectory technique presented here. | |||||
BibTeX:
@article{freitas_convective_2000, author = {Freitas, S. R. and Dias, Mafs and Dias, P. L. S. and Longo, K. M. and Artaxo, P. and Andreae, M. O. and Fischer, H.}, title = {A convective kinematic trajectory technique for low-resolution atmospheric models}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2000}, volume = {105}, number = {D19}, pages = {24375--24386}, url = {://WOS:000090029300015}, doi = {https://doi.org/10.1029/2000jd900217} } |
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Freire, L.S., Gerken, T., Ruiz-Plancarte, J., Wei, D., Fuentes, J.D., Katul, G.G., Dias, N.L., Acevedo, O.C. and Chamecki, M. | Turbulent mixing and removal of ozone within an Amazon rainforest canopy [BibTeX] |
2017 | J. Geophys. Res. Atmos. Vol. 122 |
article | DOI |
BibTeX:
@article{freire_turbulent_2017, author = {Freire, L. S. and Gerken, T. and Ruiz-Plancarte, J. and Wei, D. and Fuentes, J. D. and Katul, G. G. and Dias, N. L. and Acevedo, O. C. and Chamecki, M.}, title = {Turbulent mixing and removal of ozone within an Amazon rainforest canopy}, journal = {J. Geophys. Res. Atmos.}, year = {2017}, volume = {122}, doi = {https://doi.org/10.1002/2016JD026009} } |
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Freire, G.A.P., Ventura, D.J., Fotopoulos, I.G., Rosa, D.M., Aguiar, R.G. and Araújo, A.C.d. | DINÂMICA DE SERAPILHEIRA EM UMA ÁREA DE FLORESTA DE TERRA FIRME, AMAZÔNIA OCIDENTAL | 4 | Nativa Vol. 8(3), pp. 323-328 |
article | DOI URL |
Abstract: <p>O objetivo deste estudo foi avaliar a produção e decomposição de serapilheira em uma área de floresta primária de terra firme na Reserva Biológica do Jaru. Para tanto, foi implantada uma parcela permanente de 1 hectare, onde foram demarcadas 25 subparcelas com 20 x 20 m cada. Para a coleta de serapilheira, instalou-se 25 coletores de PVC (1 em cada centro da subparcela), medindo 0,25 m², a 1 metro do solo, com malha de <em>nylon</em> de 1 mm. Para estimar o estoque de serapilheira, utilizou-se 25 coletores de madeira, medindo 0,25 m², com malha de <em>nylon</em> de 1 mm, dispostos no solo de cada subparcela. As coletas da pesquisa foram realizadas quinzenalmente, entre os meses de outubro de 2016 a setembro de 2017, e a serapilheira triada nas frações: folha, galho, material reprodutivo e miscelânea. No laboratório, os materiais amostrados foram secos em estufa à 80 ºC e pesados em balança de precisão centesimal, sendo que a decomposição de serapilheira foi estimada através da relação entre produção e estoque. De acordo com os resultados obtidos, a produção de serapilheira total foi de 14,13 Mg ha<sup>-1</sup> e as frações seguiram o padrão: folha&gt;miscelânea&gt;galho&gt;material reprodutivo. As maiores produções aconteceram na estação seca e a taxa de decomposição foi 1,37, indicando que a atividade microbiana na área de estudo é acelerada.</p><p><strong>Palavras-chave:</strong> dinâmica sazonal; nutrição de plantas; ecologia florestal; decomposição.</p><p align="center"> </p><p><strong>LITTER DYNAMICS IN A FOREST AREA OF GROUND FIRM, WESTERN AMAZON</strong></p><p align="center"> </p><p><strong>ABSTRACT:</strong></p><p>The objective of this study was to evaluate the litter production and decomposition in an area of primary upland forest in the Jaru Biological Reserve. For that, a permanent plot of 1 hectare was implanted, where 25 subplots with 20 x 20 m each were demarcated. For the collection of litter, 25 PVC collectors were installed (1 in each center of the subplot), measuring 0.25 m², 1 meter from the ground, with 1 mm nylon mesh. To estimate the litter stock, 25 wood collectors, measuring 0.25 m², with 1 mm nylon mesh, were used, arranged in the soil of each subplot. The collections of the research were carried out fortnightly, between the months of October 2016 and September 2017, and the litter is sorted in the fractions: leaf, branch, reproductive material and miscellaneous. In the laboratory, the sampled materials were dried in an oven at 80 ºC and weighed on a centesimal precision scale, and the litter decomposition was estimated through the relationship between production and stock. According to the results obtained, the total litter production was 14.13 Mg ha<sup>-1</sup> and the fractions followed the pattern: leaf&gt;miscellaneous&gt;branch&gt;reproductive material. The highest yields occurred in the dry season and the decomposition rate was 1.37, indicating that the microbial activity in the study area is accelerated.</p><p><strong>Keyword:</strong> seasonal dynamics; plant nutrition; forest ecology; decomposition.</p> | |||||
BibTeX:
@article{freire_dinamica_4, author = {Freire, Gabriel Araújo Paes and Ventura, Dione Judite and Fotopoulos, Igor Georgios and Rosa, Diogo Martins and Aguiar, Renata Gonçalves and Araújo, Alessandro Carioca de}, title = {DINÂMICA DE SERAPILHEIRA EM UMA ÁREA DE FLORESTA DE TERRA FIRME, AMAZÔNIA OCIDENTAL}, journal = {Nativa}, year = {4}, volume = {8}, number = {3}, pages = {323--328}, url = {https://periodicoscientificos.ufmt.br/ojs/index.php/nativa/article/view/9155}, doi = {https://doi.org/10.31413/nativa.v8i3.9155} } |
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Freire, A.S.C., Vitorino, M.I., de Souza, A.M.L. and Germano, M.F. | Analysis of the energy balance and CO2 flow under the influence of the seasonality of climatic elements in a mangrove ecosystem in Eastern Amazon | 2022 | International Journal of Biometeorology Vol. 66(4), pp. 647-659 |
article | DOI URL |
Abstract: An unprecedented study was carried out in a mangrove ecosystem in the northeastern coast of the Brazilian Amazon to understand the behavior of climatic elements in a year with the occurrence of El Niño (2015), associated with the seasonal function source/sink of CO2 by the ecosystem. Global radiation (Rg), net radiation (Rn), temperature, relative humidity, precipitation, horizontal wind speed and direction, as well as turbulent flows of sensible heat (H), latent heat (LE), and carbon (f_CO2) were recorded using eddy covariance, a system for studying turbulent flows of heat and gases in the atmosphere. We observed a drastic reduction in rainfall volumes, which accounts for 63.7% of the expected total according to the region’s climatology. Regarding f_ CO2, the highest values of photosynthesis, autotrophic, and heterotrophic respiration of the ecosystem occurred in the wet season due to precipitation, ideal photosynthetically active radiation, lower soil salinity, and higher NDVI of the ecosystem. In the 2nd semester of the year, we observed that the decrease in cloudiness, causing a higher radiation supply in the forest canopy, accompanied by a reduction in precipitation and an increase in the value of H and soil salinity, favored the increase of foliar abscission by the dominant genus Rhizophora and Avicennia, thus influencing the reduction of magnitudes of carbon source/sink functions in the ecosystem during this season, even on high tide days. | |||||
BibTeX:
@article{freire_analysis_2022, author = {Freire, Antonio Sérgio C. and Vitorino, Maria Isabel and de Souza, Adriano Marlisson L. and Germano, Michell Fontenelle}, title = {Analysis of the energy balance and CO2 flow under the influence of the seasonality of climatic elements in a mangrove ecosystem in Eastern Amazon}, journal = {International Journal of Biometeorology}, year = {2022}, volume = {66}, number = {4}, pages = {647--659}, url = {https://doi.org/10.1007/s00484-021-02224-8}, doi = {https://doi.org/10.1007/s00484-021-02224-8} } |
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Freeman, A., Chapman, B. and Siqueira, P. | The JERS-1 Amazon Multi-season Mapping Study (JAMMS): Science objectives and implications for future missions | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1447-1460 |
article | DOI URL |
Abstract: In late September 1995, the National Space Development Agency of Japan (NASDA) began a new phase of operations for the Japanese Earth Remote Sensing satellite (JERS-1) Synthetic Aperture Radar (SAR)-the Global Rain Forest Mapping (GRFM) project. The first rainforest area to be mapped was the Amazon basin, between September and November of that year (the low flood season for much of the region), in support of the JERS-1 Amazon Multi-season Study (JAMMS), sponsored by NASA. This data acquisition was repeated 6 months later to acquire a second map of the Amazon, during the high flood season in May/June of 1996. The main objective of the JAMMS project was to generate a map of inundation over the Amazon basin by comparing data from the high- and low-flood seasons. Most of the data collected during these two phases of the JAMMS project, a total of similar to5000 frames of data, was received and processed by the Alaska SAR Facility (ASF), then sent to the Jet Propulsion Laboratory (JPL) and NASDA for post-processing and analysis. The quality of the data processed by ASF for the JAMMS project has proved to be exceptional. This paper is a summary of the JAMMS project, which has resulted in a scientific dataset of very high value-a multi-season snapshot of one of the most difficult areas on Earth to monitor, even from space. | |||||
BibTeX:
@article{freeman_jers-1_2002, author = {Freeman, A. and Chapman, B. and Siqueira, P.}, title = {The JERS-1 Amazon Multi-season Mapping Study (JAMMS): Science objectives and implications for future missions}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1447--1460}, url = {://WOS:000174661900013}, doi = {https://doi.org/10.1080/01431160110092975} } |
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Fraund, M., Pham, D., Bonanno, D., Harder, T., Wang, B., Brito, J., de Sá, S., Carbone, S., China, S., Artaxo, P., Martin, S., Pöhlker, C., Andreae, M., Laskin, A., Gilles, M. and Moffet, R. | Elemental Mixing State of Aerosol Particles Collected in Central Amazonia during GoAmazon 2014/15 [BibTeX] |
2017 | Atmosphere Vol. 8, pp. 173 |
article | |
BibTeX:
@article{fraund_elemental_2017, author = {Fraund, M. and Pham, D.Q. and Bonanno, D. and Harder, T.H. and Wang, B. and Brito, J. and de Sá, S.S. and Carbone, S. and China, S. and Artaxo, P. and Martin, S.T. and Pöhlker, C. and Andreae, M.O. and Laskin, A. and Gilles, M.K. and Moffet, R.C.}, title = {Elemental Mixing State of Aerosol Particles Collected in Central Amazonia during GoAmazon 2014/15}, journal = {Atmosphere}, year = {2017}, volume = {8}, pages = {173} } |
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Franklin, E.B., Yee, L.D., Wernis, R., Isaacman-VanWertz, G., Kreisberg, N., Weber, R., Zhang, H., Palm, B.B., Hu, W., Campuzano-Jost, P., Day, D.A., Manzi, A., Artaxo, P., Souza, R.A.F.D., Jimenez, J.L., Martin, S.T. and Goldstein, A.H. | Chemical Signatures of Seasonally Unique Anthropogenic Influences on Organic Aerosol Composition in the Central Amazon [BibTeX] |
2023 | Environmental Science & Technology Vol. 57(15), pp. 6263-6272 |
article | DOI URL |
BibTeX:
@article{franklin_chemical_2023, author = {Franklin, Emily B. and Yee, Lindsay D. and Wernis, Rebecca and Isaacman-VanWertz, Gabriel and Kreisberg, Nathan and Weber, Robert and Zhang, Haofei and Palm, Brett B. and Hu, Weiwei and Campuzano-Jost, Pedro and Day, Douglas A. and Manzi, Antonio and Artaxo, Paulo and Souza, Rodrigo A. F. De and Jimenez, Jose L. and Martin, Scot T. and Goldstein, Allen H.}, title = {Chemical Signatures of Seasonally Unique Anthropogenic Influences on Organic Aerosol Composition in the Central Amazon}, journal = {Environmental Science & Technology}, year = {2023}, volume = {57}, number = {15}, pages = {6263--6272}, url = {https://doi.org/10.1021/acs.est.2c07260}, doi = {https://doi.org/10.1021/acs.est.2c07260} } |
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Franklin, E., Magnusson, W.E. and Luizao, F.J. | Relative effects of biotic and abiotic factors on the composition of soil invertebrate communities in an Amazonian savanna | 2005 | Applied Soil Ecology Vol. 29(3), pp. 259-273 |
article | DOI URL |
Abstract: Using ordinations techniques, we investigated the effects of different types of plant cover on the relationship between soil structure and invertebrate communities in an Amazonian savanna. Vegetation islands were chosen where four selected shrubs species were present on sandy and clayey soils. For each sample under a selected shrub within the clump, another sample was taken in the grass-tuft and extracted in Berlese-Tullgren. Classifying at higher taxonomic levels, we detected 27 zoological categories. The mean number of individuals was generally higher on shrubs. Acari and Collembola were the dominant groups. Non-Oribatid mites dominated in the savanna, in contrary with what occurs in most Amazonian ecosystems, where the dominance of Oribatida is always higher than others Acari. The level of taxonomic resolution utilized was sufficient to show the main differences of the spatial variation in community structure. We detected effects of soil type, vegetation structure and plant specie identity on the composition of the communities. The mesofauna have a mosaic distribution in the savanna dependent on the soil-food web structure of the vegetation. Shrubs and grass-tuft generate different ecosystems. Therefore, studies with better taxonomic resolution will be necessary to assess the magnitude of the effect of biotic and abiotic factors. (C) 2005 Elsevier B.V All rights reserved. | |||||
BibTeX:
@article{franklin_relative_2005, author = {Franklin, E. and Magnusson, W. E. and Luizao, F. J.}, title = {Relative effects of biotic and abiotic factors on the composition of soil invertebrate communities in an Amazonian savanna}, journal = {Applied Soil Ecology}, year = {2005}, volume = {29}, number = {3}, pages = {259--273}, url = {://WOS:000229789700006}, doi = {https://doi.org/10.1016/j.apsoil.2004.12.004} } |
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Franco, M.A., Ditas, F., Kremper, L.A., Machado, L.A.T., Andreae, M.O., Araújo, A., Barbosa, H.M.J., de Brito, J.F., Carbone, S., Holanda, B.A., Morais, F.G., Nascimento, J.P., Pöhlker, M.L., Rizzo, L.V., Sá, M., Saturno, J., Walter, D., Wolff, S., Pöschl, U., Artaxo, P. and Pöhlker, C. | Occurrence and growth of sub-50 nm aerosol particles in the Amazonian boundary layer [BibTeX] |
2022 | Atmos. Chem. Phys. Vol. 22(5), pp. 3469-3492 |
article | DOI URL |
BibTeX:
@article{franco_occurrence_2022, author = {Franco, M. A. and Ditas, F. and Kremper, L. A. and Machado, L. A. T. and Andreae, M. O. and Araújo, A. and Barbosa, H. M. J. and de Brito, J. F. and Carbone, S. and Holanda, B. A. and Morais, F. G. and Nascimento, J. P. and Pöhlker, M. L. and Rizzo, L. V. and Sá, M. and Saturno, J. and Walter, D. and Wolff, S. and Pöschl, U. and Artaxo, P. and Pöhlker, C.}, title = {Occurrence and growth of sub-50 nm aerosol particles in the Amazonian boundary layer}, journal = {Atmos. Chem. Phys.}, year = {2022}, volume = {22}, number = {5}, pages = {3469--3492}, url = {https://acp.copernicus.org/articles/22/3469/2022/}, doi = {https://doi.org/10.5194/acp-22-3469-2022} } |
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Franchito, S.H., Moraes, E.C. and Rao, V.B. | Simulations with a radiation model and comparisons with LBA data sets | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) data are used to estimate and validate infrared and solar radiation models calculations of Chou and Suarez [1994, 1999]. The models are tested for two contrasting vegetation regions. forest and grassland. Observed data of several days and different times of a day collected in the two sites are used to test the models. The results show that the model simulations in general agree well with the observations for both the forest and grassland cases. The mean errors are around the same order or lower than the instrument errors, except in the case of the reflected solar radiation. The radiation fluxes are strongly correlated with the observed data, significant at 99% confidence level, except in the case of the downward longwave radiation. The use of the Bonferrone technique confirmed the information given by the correlation coefficient calculations. | |||||
BibTeX:
@article{franchito_simulations_2002, author = {Franchito, S. H. and Moraes, E. C. and Rao, V. B.}, title = {Simulations with a radiation model and comparisons with LBA data sets}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200121}, doi = {https://doi.org/10.1029/2001jd001356} } |
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Franca Resende, J.C., Markewitz, D., Klink, C.A., da Cunha Bustamante, M.M. and Davidson, E.A. | Phosphorus cycling in a small watershed in the Brazilian Cerrado: impacts of frequent burning | 2011 | Biogeochemistry Vol. 105(1-3), pp. 105-118 |
article | DOI URL |
Abstract: Plant productivity in many tropical savannas is phosphorus limited. The biogeochemical cycling of P in these ecosystems, however, has not been well quantified. In the present study, we characterized P stocks and fluxes in a well-preserved small watershed in the Brazilian Cerrado. As the Cerrado is also a fire-dominated ecosystem, we measured the P stocks and fluxes in a cerrado stricto sensu plot with complete exclusion of fire for 26 years (unburned plot) and then tested some predictions about the impacts of fire impacts on P cycling in an experimental plot that was burned three times since 1992 (burned plot). The unburned area is an ecosystem with large soil stocks of total P (1,151 kg ha(-1) up to 50 cm depth), but the largest fraction is in an occluded form. Readily extractable P was found up to 3 m soil depth suggesting that deep soil is more important to the P cycle than has been recognized. The P stock in belowground biomass (0-800 cm) was 9.9 kg ha(-1). Decomposition of fine litter released 0.97 kg P ha(-1) year(-1). Fluxes of P through bulk atmospheric deposition, throughfall and litter leachate were very low (0.008, 0.006 and 0.028 kg ha(-1) year(-1), respectively) as was stream export (0.001 kg ha(-1) year(-1)). Immobilization of P by microbes during the rainy season seems to be an important mechanism of P conservation in this ecosystem. Fire significantly increased P flux in litter leachate to 0.11 kg ha(-1) year(-1), and added 1.2 kg ha(-1) of P in ash deposition after fire. We found an increase of P concentration in soil solution at 100 cm depth (from 0.03 mu g l(-1) in unburned plot to 0.3 mu g l(-1) in the burned plot). In surface soils (0-10 cm) of the burned plot, fire decreased the concentrations of extractable organic-P fractions, but did not significantly increase inorganic-P fractions. The reduction of extractable soil organic P in the burned plot in topsoil and the increase of P in the soil solution at greater depths indicated a reduction of P availability and may increase P fixation in deep soils. Repeated fire events over the long term may result in significant net loss of available forms of phosphorus from this ecosystem. | |||||
BibTeX:
@article{franca_resende_phosphorus_2011, author = {Franca Resende, Julio Carlos and Markewitz, Daniel and Klink, Carlos Augusto and da Cunha Bustamante, Mercedes Maria and Davidson, Eric A.}, title = {Phosphorus cycling in a small watershed in the Brazilian Cerrado: impacts of frequent burning}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {105--118}, url = {://WOS:000294501100008}, doi = {https://doi.org/10.1007/s10533-010-9531-5} } |
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Franca, H. and Setzer, A.W. | AVHRR analysis of a savanna site through a fire season in Brazil | 2001 | International Journal of Remote Sensing Vol. 22(13), pp. 2449-2461 |
article | DOI URL |
Abstract: A temporal sequence of images form the Advanced Very High Resolution Radiometer (AVHRR) orbital sensor along 1.5 year was used to study the response of a savanna site that burnt in the dry season. The Emas National Park of Brazil was monitored with 1.1 km high resolution afternoon images from June 1992 to October 1993 through the responses of channels 1 (0.6 mum), 2 (0.9 mum), 3 (3.7 mum). and of the Normalized Difference Vegetation Index (NDVI) combination of channels 1 and 2. A fire consumed 23% of the park's 1300 km(2) surface in August 1992, based on a subsequent Landsat Thematic Mapper image. three sub-areas that burnt were chosen for a detailed AVHRR comparative analysis with five sub-areas that did not burn. From the 344 images recorded on different days only 26 were effectively useful, Channel 1 showed little difference for burnt and unburnt vegetation. Channel 2 and NDVI displayed strong evidence of the fire for up to 13 months, while in channel 3 this period was less than 8 months. However, channel 3 and NDVI presented the strongest evidence of the fire occurrence on a short-term basis. The results support the use of AVHRR products based on channels 2 and 3 to monitor and evaluate the extent of vegetation burn and regrowth in savannas, important information for tropical vegetation. | |||||
BibTeX:
@article{franca_avhrr_2001, author = {Franca, H. and Setzer, A. W.}, title = {AVHRR analysis of a savanna site through a fire season in Brazil}, journal = {International Journal of Remote Sensing}, year = {2001}, volume = {22}, number = {13}, pages = {2449--2461}, url = {://WOS:000170557000002}, doi = {https://doi.org/10.1080/01431160120029} } |
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Forsberg, BR, Dunne, T, Barthem, RB, Goulding, M, Paiva, RCD, et al. and Melack, JM | The potential impact of new Andean dams on Amazon fluvial ecosystems [BibTeX] |
2017 | PLoS ONE Vol. 12(8), pp. e0182254 |
article | DOI |
BibTeX:
@article{forsberg_br_potential_2017, author = {Forsberg BR, Dunne T, Barthem RB, Goulding M, Paiva RCD, et al., Melack JM}, title = {The potential impact of new Andean dams on Amazon fluvial ecosystems}, journal = {PLoS ONE}, year = {2017}, volume = {12}, number = {8}, pages = {e0182254}, doi = {https://doi.org/10.1371/journal.pone.0182254} } |
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Forsberg, B.R., Hashimoto, Y., Rosenqvist, A. and de Miranda, F.P. | Tectonic fault control of wetland distributions in the Central Amazon revealed by JERS-1 radar imagery | 2000 | Quaternary International Vol. 72, pp. 61-66 |
article | DOI URL |
Abstract: A mosaic of JERS-1 L-band synthetic aperture radar (SAR) images was used to investigate the influence of tectonic faults on wetland distributions in similar to 200,000 km(2) of central Amazon lowland (0-4 degrees Lat. S, 60-64 degrees Long. W). The geographic distribution of hooded wetland was clearly evident on the mosaic due to the unique characteristics oil-band radar. Two distinct linear boundaries were encountered limiting the northern distribution of wetlands, one north of the Negro river main channel and west of the Branco river, oriented WNW-ESE, and one south of the Negro main channel and east of the Branco, oriented NW-SE. The orientations and positions of these boundaries were consistent with the prevailing tectonic fracture pattern in the region. Geophysical, pedological and geomorphological data supported the hypothesis that these boundaries are tectonically controlled. The ecological, economic and biogeochemical implications of the observed wetland distribution were considered. The distributions of wetland-dependent biota were expected to be severely limited north of the Negro main channel. Fish production, wetland timber yields and methane emissions were also predicted to be exceptionally low in this region. (C) 2000 Elsevier Science Ltd and INQUA. All rights reserved. | |||||
BibTeX:
@article{forsberg_tectonic_2000, author = {Forsberg, B. R. and Hashimoto, Y. and Rosenqvist, A. and de Miranda, F. P.}, title = {Tectonic fault control of wetland distributions in the Central Amazon revealed by JERS-1 radar imagery}, journal = {Quaternary International}, year = {2000}, volume = {72}, pages = {61--66}, url = {://WOS:000089703700007}, doi = {https://doi.org/10.1016/s1040-6182(00)00021-5} } |
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Fors, E.O., Rissler, J., Massling, A., Svenningsson, B., Andreae, M.O., Dusek, U., Frank, G.P., Hoffer, A., Bilde, M., Kiss, G., Janitsek, S., Henning, S., Facchini, M.C., Decesari, S. and Swietlicki, E. | Hygroscopic properties of Amazonian biomass burning and European background HULIS and investigation of their effects on surface tension with two models linking H-TDMA to CCNC data | 2010 | Atmospheric Chemistry and Physics Vol. 10(12), pp. 5625-5639 |
article | DOI URL |
Abstract: HUmic-LIke Substances (HULIS) have been identified as major contributors to the organic carbon in atmospheric aerosol. The term "HULIS" is used to describe the organic material found in aerosol particles that resembles the humic organic material in rivers and sea water and in soils. In this study, two sets of filter samples from atmospheric aerosols were collected at different sites. One set of samples was collected at the K-puszta rural site in Hungary, about 80 km SE of Budapest, and a second was collected at a site in Rondonia, Amazonia, Brazil, during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Smoke Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) biomass burning season experiment. HULIS were extracted from the samples and their hygroscopic properties were studied using a Hygroscopicity Tandem Differential Mobility Analyzer (H-TDMA) at relative humidity (RH) textless 100%, and a cloud condensation nucleus counter (CCNC) at RH textgreater 100%. The H-TDMA measurements were carried out at a dry diameter of 100 nm and for RH ranging from 30 to 98%. At 90% RH the HULIS samples showed diameter growth factors between 1.04 and 1.07, reaching values of 1.4 at 98% RH. The cloud nucleating properties of the two sets of aerosol samples were analysed using two types of thermal static cloud condensation nucleus counters. Two different parameterization models were applied to investigate the potential effect of HULIS surface activity, both yielding similar results. For the K-puszta winter HULIS sample, the surface tension at the point of activation was estimated to be lowered by between 34% (47.7 mN/m) and 31% (50.3 mN/m) for dry sizes between 50 and 120 nm in comparison to pure water. A moderate lowering was also observed for the entire water soluble aerosol sample, including both organic and inorganic compounds, where the surface tension was decreased by between 2% (71.2 mN/m) and 13% (63.3 mN/m). | |||||
BibTeX:
@article{fors_hygroscopic_2010, author = {Fors, E. O. and Rissler, J. and Massling, A. and Svenningsson, B. and Andreae, M. O. and Dusek, U. and Frank, G. P. and Hoffer, A. and Bilde, M. and Kiss, G. and Janitsek, S. and Henning, S. and Facchini, M. C. and Decesari, S. and Swietlicki, E.}, title = {Hygroscopic properties of Amazonian biomass burning and European background HULIS and investigation of their effects on surface tension with two models linking H-TDMA to CCNC data}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {12}, pages = {5625--5639}, url = {://WOS:000279391100022}, doi = {https://doi.org/10.5194/acp-10-5625-2010} } |
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Formenti, P., Andreae, M.O., Lange, L., Roberts, G., Cafmeyer, J., Rajta, I., Maenhaut, W., Holben, B.N., Artaxo, P. and Lelieveld, J. | Saharan dust in Brazil and Suriname during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) - Cooperative LBA Regional Experiment (CLAIRE) in March 1998 | 2001 | Journal of Geophysical Research-Atmospheres Vol. 106(D14), pp. 14919-14934 |
article | DOI URL |
Abstract: Advection of Saharan dust was observed via chemical and optical measurements during March 1998 in Brazil and Suriname during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)-Cooperative LBA Airborne Regional Experiment (CLAIRE)-98 experiment. In Brazil the dust outbreak produced an increase of a factor of 3 in the daily mean mass concentration (up to 26 +/- 7 mug m(-3)) of particles smaller than 10 mum equivalent aerodynamic diameter (EAD), and in the daily mean aerosol particle scattering coefficient sigma (N) (up to 26 +/- 8 Mm(-1) STP, ambient humidity). Background levels of aerosol scattering (ambient) were sigma (s) similar to 10 Mm(-1). The effect of dust advection was evident for all major crustal elements (Al, Si, Ca, Ti, Mn, and Fe), as well as the sea-salt elements (Na, Cl, and S), as the dust layer was transported at low altitude (below 800 hPa). Coarse P and organic carbon (OC) concentrations were not influenced by the occurrence of dust, and were mainly emitted by the rain forest. The dry scattering mass efficiency of dust (particles smaller than 10 mum EAD) was estimated to be between 0.65 (+/- 0.06) and 0.89 (+/- 0.08) m(2) g(-1). Airborne profiles of aerosol scattering showed two distinct types of vertical structure in the dust layer over Suriname, either vertically uniform (15, 26 March), or plume-like (25 March). Dust layers extended generally up to 700 hPa, while scattering layers occasionally encountered at higher altitudes resulted from smoke emitted by biomass burning in Venezuela and Colombia, Observations in South America were supported by measurements in Israel and Tenerife (Canary Islands), where the dust outbreaks were also detected. | |||||
BibTeX:
@article{formenti_saharan_2001, author = {Formenti, P. and Andreae, M. O. and Lange, L. and Roberts, G. and Cafmeyer, J. and Rajta, I. and Maenhaut, W. and Holben, B. N. and Artaxo, P. and Lelieveld, J.}, title = {Saharan dust in Brazil and Suriname during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) - Cooperative LBA Regional Experiment (CLAIRE) in March 1998}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2001}, volume = {106}, number = {D14}, pages = {14919--14934}, url = {://WOS:000170109700014}, doi = {https://doi.org/10.1029/2000jd900827} } |
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Fontesa, C.G., Chambers, J.Q. and Higuchi, N. | Revealing the causes and temporal distribution of tree mortality in Central Amazonia [BibTeX] |
2018 | Forest Ecology and Management Vol. 424, pp. 177-183 |
article | |
BibTeX:
@article{fontesa_revealing_2018, author = {Fontesa, C. G. and Chambers, J. Q. and Higuchi, N.}, title = {Revealing the causes and temporal distribution of tree mortality in Central Amazonia}, journal = {Forest Ecology and Management}, year = {2018}, volume = {424}, pages = {177--183} } |
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Fontes Molleri, G.S., Kampel, M. and Ledo de Moraes Novo, E.M. | Spectral classification of water masses under the influence of the Amazon River plume | 2010 | Acta Oceanologica Sinica Vol. 29(3), pp. 1-8 |
article | DOI URL |
Abstract: The large amount of dissolved and particulate material discharged by the Amazon River into the Equatorial Atlantic Ocean cause distinct spectral response of its waters as compared to the nearby ocean waters. This paper shows the application of K-means clustering algorithm for classifying water masses in the region under the Amazon River plume influence according to their spectral behavior. Salinity and temperature data from 67 oceanographic stations were related to Sea-viewing Wide Field-of-view Sensor (SeaWiFS) remote sensing reflectances values and the following bio-optical products: (i) chlorophyll-a concentration, (ii) water attenuation coefficient and (iii) absorption coefficient for dissolved and detrital material. Four different water masses were identified such as: (1) oceanic water, (2) intermediate oceanic water, (3) intermediate river plume water and (4) Amazon River plume water. The spectral behavior of these water masses allowed concluding that the main active optical component of the waters in the region is the colored dissolved organic matter originated mostly from the Amazon River. | |||||
BibTeX:
@article{fontes_molleri_spectral_2010, author = {Fontes Molleri, Gustavo Souto and Kampel, Milton and Ledo de Moraes Novo, Evlyn Marcia}, title = {Spectral classification of water masses under the influence of the Amazon River plume}, journal = {Acta Oceanologica Sinica}, year = {2010}, volume = {29}, number = {3}, pages = {1--8}, url = {://WOS:000279357100001}, doi = {https://doi.org/10.1007/s13131-010-0031-1} } |
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Fontes, C.G., Fine, P.V.A., Wittmann, F., Bittencourt, P.R.L., Piedade, M.T.F., Higuchi, N., Chambers, J.Q. and Dawson, T.E. | Convergent evolution of tree hydraulic traits in Amazonian habitats: implications for community assemblage and vulnerability to drought | 2020 | New Phytologist Vol. 228(1), pp. 106-120 |
article | DOI URL |
Abstract: Summary Amazonian droughts are increasing in frequency and severity. However, little is known about how this may influence species-specific vulnerability to drought across different ecosystem types. We measured 16 functional traits for 16 congeneric species from six families and eight genera restricted to floodplain, swamp, white-sand or plateau forests of Central Amazonia. We investigated whether habitat distributions can be explained by species hydraulic strategies, and if habitat specialists differ in their vulnerability to embolism that would make water transport difficult during drought periods. We found strong functional differences among species. Nonflooded species had higher wood specific gravity and lower stomatal density, whereas flooded species had wider vessels, and higher leaf and xylem hydraulic conductivity. The P50 values (water potential at 50% loss of hydraulic conductivity) of nonflooded species were significantly more negative than flooded species. However, we found no differences in hydraulic safety margin among species, suggesting that all trees may be equally likely to experience hydraulic failure during severe droughts. Water availability imposes a strong selection leading to differentiation of plant hydraulic strategies among species and may underlie patterns of adaptive radiation in many tropical tree genera. Our results have important implications for modeling species distribution and resilience under future climate scenarios. | |||||
BibTeX:
@article{fontes_convergent_2020, author = {Fontes, Clarissa G. and Fine, Paul V. A. and Wittmann, Florian and Bittencourt, Paulo R. L. and Piedade, Maria Teresa Fernandez and Higuchi, Niro and Chambers, Jeffrey Q. and Dawson, Todd E.}, title = {Convergent evolution of tree hydraulic traits in Amazonian habitats: implications for community assemblage and vulnerability to drought}, journal = {New Phytologist}, year = {2020}, volume = {228}, number = {1}, pages = {106--120}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.16675}, doi = {https://doi.org/10.1111/nph.16675} } |
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Fontes, C.G., Dawson, T.E., Jardine, K., McDowell, N., Gimenez, B.O., Anderegg, L., Negrón-Juárez, R., Higuchi, N., Fine, P.V.A., Araújo, A.C. and Chambers, J.Q. | Dry and hot: the hydraulic consequences of a climate change–type drought for Amazonian trees | 2018 | Philosophical Transactions of the Royal Society B: Biological Sciences Vol. 373(1760), pp. 20180209 |
article | DOI URL |
Abstract: How plants respond physiologically to leaf warming and low water availability may determine how they will perform under future climate change. In 2015–2016, an unprecedented drought occurred across Amazonia with record-breaking high temperatures and low soil moisture, offering a unique opportunity to evaluate the performances of Amazonian trees to a severe climatic event. We quantified the responses of leaf water potential, sap velocity, whole-tree hydraulic conductance (Kwt), turgor loss and xylem embolism, during and after the 2015–2016 El Niño for five canopy-tree species. Leaf/xylem safety margins (SMs), sap velocity and Kwt showed a sharp drop during warm periods. SMs were negatively correlated with vapour pressure deficit, but had no significant relationship with soil water storage. Based on our calculations of canopy stomatal and xylem resistances, the decrease in sap velocity and Kwt was due to a combination of xylem cavitation and stomatal closure. Our results suggest that warm droughts greatly amplify the degree of trees' physiological stress and can lead to mortality. Given the extreme nature of the 2015–2016 El Niño and that temperatures are predicted to increase, this work can serve as a case study of the possible impact climate warming can have on tropical trees. This article is part of a discussion meeting issue ‘The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications’. | |||||
BibTeX:
@article{fontes_dry_2018, author = {Fontes, Clarissa G. and Dawson, Todd E. and Jardine, Kolby and McDowell, Nate and Gimenez, Bruno O. and Anderegg, Leander and Negrón-Juárez, Robinson and Higuchi, Niro and Fine, Paul V. A. and Araújo, Alessandro C. and Chambers, Jeffrey Q.}, title = {Dry and hot: the hydraulic consequences of a climate change–type drought for Amazonian trees}, journal = {Philosophical Transactions of the Royal Society B: Biological Sciences}, year = {2018}, volume = {373}, number = {1760}, pages = {20180209}, url = {https://royalsocietypublishing.org/doi/abs/10.1098/rstb.2018.0209}, doi = {https://doi.org/10.1098/rstb.2018.0209} } |
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Foley, J.A., Levis, S., Costa, M.H., Cramer, W. and Pollard, D. | Incorporating dynamic vegetation cover within global climate models | 2000 | Ecological Applications Vol. 10(6), pp. 1620-1632 |
article | DOI URL |
Abstract: Numerical models of Earth's climate system must consider the atmosphere and terrestrial biosphere as a coupled system, with biogeophysical and biogeochemical processes occurring across a range of timescales. On short timescales (i.e., seconds to hours), the coupled system is dominated by the rapid biophysical and biogeochemical processes that exchange energy, water, carbon dioxide, and momentum between the atmosphere and the land surface. Intermediate-timescale (i.e., days to months) processes include changes in the store of soil moisture, changes in carbon allocation, and vegetation phenology (e.g., budburst, leaf-out, senescence, dormancy). On longer timescales (i.e., seasons, years, and decades), there can be fundamental changes in the vegetation structure itself (disturbance, land use, stand growth). In order to consider the full range of coupled atmosphere-biosphere processes, we must extend climate models to include intermediate and long-term ecological phenomena. This paper reviews early attempts at linking climate and equilibrium vegetation models through iterative coupling techniques, and some important insights gained through this procedure. We then summarize recent developments in coupling global vegetation and climate models, and some of the applications of these tools to modeling climate change. Furthermore, we discuss more recent developments in vegetation models (including a new class of models called "dynamic global vegetation models"), and how these models are incorporated with atmospheric general circulation models. Fully coupled climate-vegetation models are still in the very early stages of development. Nevertheless, these prototype models have already indicated the importance of considering vegetation cover as an interactive part of the climate system. | |||||
BibTeX:
@article{foley_incorporating_2000, author = {Foley, J. A. and Levis, S. and Costa, M. H. and Cramer, W. and Pollard, D.}, title = {Incorporating dynamic vegetation cover within global climate models}, journal = {Ecological Applications}, year = {2000}, volume = {10}, number = {6}, pages = {1620--1632}, url = {://WOS:000165680300005}, doi = {https://doi.org/10.2307/2641227} } |
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Foley, J.A., DeFries, R., Asner, G.P., Barford, C., Bonan, G., Carpenter, S.R., Chapin, F.S., Coe, M.T., Daily, G.C., Gibbs, H.K., Helkowski, J.H., Holloway, T., Howard, E.A., Kucharik, C.J., Monfreda, C., Patz, J.A., Prentice, I.C., Ramankutty, N. and Snyder, P.K. | Global consequences of land use | 2005 | Science Vol. 309(5734), pp. 570-574 |
article | DOI URL |
Abstract: Land use has generally been considered a local environmental issue, but it is becoming a force of global importance. Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water, and shelter to more than six billion people. Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, along with considerable tosses of biodiversity. Such changes in land use have enabled humans to appropriate an increasing share of the planet's resources, but they also potentially undermine the capacity of ecosystems to sustain food production, maintain freshwater and forest resources, regulate climate and air quality, and ameliorate infectious diseases. We face the challenge of managing trade-offs between immediate human needs and maintaining the capacity of the biosphere to provide goods and services in the long term. | |||||
BibTeX:
@article{foley_global_2005, author = {Foley, J. A. and DeFries, R. and Asner, G. P. and Barford, C. and Bonan, G. and Carpenter, S. R. and Chapin, F. S. and Coe, M. T. and Daily, G. C. and Gibbs, H. K. and Helkowski, J. H. and Holloway, T. and Howard, E. A. and Kucharik, C. J. and Monfreda, C. and Patz, J. A. and Prentice, I. C. and Ramankutty, N. and Snyder, P. K.}, title = {Global consequences of land use}, journal = {Science}, year = {2005}, volume = {309}, number = {5734}, pages = {570--574}, note = {Edition: 2005/07/26}, url = {://WOS:000230735200036}, doi = {https://doi.org/10.1126/science.1111772} } |
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Foley, J.A., Costa, M.H., Delire, C., Ramankutty, N. and Snyder, P. | Green Surprise? How Terrestrial Ecosystems Could Affect Earth's Climate | 2003 | Frontiers in Ecology and the Environment Vol. 1(1), pp. 38 |
article | DOI URL |
Abstract: While the earth's climate can affect the structure and functioning of terrestrial ecosystems, the process also works in reverse. As a result, changes in terrestrial ecosystems may influence climate through both biophysical and biogeochemical processes. This two-way link between the physical climate system and the biosphere is under increasing scrutiny. We review recent developments in the analysis of this interaction, focusing in particular on how alterations in the structure and functioning of terrestrial ecosystems, through either human land-use practices or global climate change, may affect the future of the earth's climate. | |||||
BibTeX:
@article{foley_green_2003, author = {Foley, Jonathan A. and Costa, Marcos Heil and Delire, Christine and Ramankutty, Navin and Snyder, Peter}, title = {Green Surprise? How Terrestrial Ecosystems Could Affect Earth's Climate}, journal = {Frontiers in Ecology and the Environment}, year = {2003}, volume = {1}, number = {1}, pages = {38}, url = {://WOS:000221789300018}, doi = {https://doi.org/10.2307/3867963} } |
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Foley, J.A., Botta, A., Coe, M.T. and Costa, M.H. | El Nino-Southern Oscillation and the climate, ecosystems and rivers of Amazonia | 2002 | Global Biogeochemical Cycles Vol. 16(4) |
article | DOI URL |
Abstract: The El Nino-Southern Oscillation (ENSO) phenomenon is one of the dominant drivers of environmental variability in the tropics. In this study, we examine the connections between ENSO and the climate, ecosystem carbon balance, surface water balance, and river hydrology of the Amazon and Tocantins river basins in South America. First we examine the climatic variability associated with ENSO. We analyze long-term historical climate records to document the "average'' climatic signature of the El Nino and La Nina phases of the ENSO cycle. Generally speaking, the "average El Nino'' is drier and warmer than normal in Amazonia, while the "average La Nina'' is wetter and cooler. While temperature changes are mostly uniform through the whole year and are spatially homogeneous, precipitation changes are stronger during the wet season (January-February-March) and are concentrated in the northern and southeastern portions of the basin. Next we use a land surface/ecosystem model (IBIS), coupled to a hydrological routing algorithm (HYDRA), to examine how ENSO affects land surface water and carbon fluxes, as well as changes in river discharge and flooding. The model results suggest several responses to ENSO: (1) During the average El Nino, there is an anomalous source of CO(2) from terrestrial ecosystems, mainly due to a decreased net primary production (NPP) in the north of the basin. There is also a decrease in river discharge along many of the rivers in the basin, which causes a decrease in flooded area along the main stem of the Amazon. (2) During the average La Nina, there is an anomalous sink of CO(2) into terrestrial ecosystems, largely due to an increase in NPP in the northern portion of the basin. In addition, there is a large increase in river discharge in the Amazon basin, especially from the northern and western tributaries. There is a corresponding increase in flooded area, largely in the northern rivers. These results illustrate that changes in water and carbon balance associated with ENSO have complex, spatially heterogeneous features across the basin. This underscores the need for comprehensive analyses, using long-term observational data and model simulations, of regional environmental systems and their response to climatic variability. | |||||
BibTeX:
@article{foley_nino-southern_2002, author = {Foley, J. A. and Botta, A. and Coe, M. T. and Costa, M. H.}, title = {El Nino-Southern Oscillation and the climate, ecosystems and rivers of Amazonia}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {4}, url = {://WOS:000181208300001}, doi = {https://doi.org/10.1029/2002gb001872} } |
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Foley, J.A., Asner, G.P., Costa, M.H., Coe, M.T., DeFries, R., Gibbs, H.K., Howard, E.A., Olson, S., Patz, J., Ramankutty, N. and Snyder, P. | Amazonia revealed: forest degradation and loss of ecosystem goods and services in the Amazon Basin | 2007 | Frontiers in Ecology and the Environment Vol. 5(1), pp. 25-32 |
article | DOI URL |
Abstract: The Amazon Basin is one of the world's most important bioregions, harboring a rich array of plant and animal species and offering a wealth of goods and services to society. For years, ecological science has shown how large-scale forest clearings cause declines in biodiversity and the availability of forest products. Yet some important changes in the rainforests, and in the ecosystem services they provide, have been underappreciated until recently. Emerging research indicates that land use in the Amazon goes far beyond clearing large areas of forest; selective logging and other canopy damage is much more pervasive than once believed. Deforestation causes collateral damage to the surrounding forests-through enhanced drying of the forest floor, increased frequency of fires, and lowered productivity. The loss of healthy forests can degrade key ecosystem services, such as carbon storage in biomass and soils, the regulation of water balance and river flow, the modulation of regional climate patterns, and the amelioration of infectious diseases. We review these newly revealed changes in the Amazon rainforests and the ecosystem services that they provide. | |||||
BibTeX:
@article{foley_amazonia_2007, author = {Foley, Jonathan A. and Asner, Gregory P. and Costa, Marcos Heil and Coe, Michael T. and DeFries, Ruth and Gibbs, Holly K. and Howard, Erica A. and Olson, Sarah and Patz, Jonathan and Ramankutty, Navin and Snyder, Peter}, title = {Amazonia revealed: forest degradation and loss of ecosystem goods and services in the Amazon Basin}, journal = {Frontiers in Ecology and the Environment}, year = {2007}, volume = {5}, number = {1}, pages = {25--32}, url = {://WOS:000244042300021 http://www.esajournals.org/doi/pdf/10.1890/1540-9295%282007%295%5B25%3AARFDAL%5D2.0.CO%3B2}, doi = {https://doi.org/10.1890/1540-9295(2007)5%5B25:arfdal%5D2.0.co;2} } |
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Flores, B.M., Piedade, M.-T.F. and Nelson, B.W. | Fire disturbance in Amazonian blackwater floodplain forests [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 319-328 |
article | |
BibTeX:
@article{flores_fire_2014, author = {Flores, Bernardo M. and Piedade, Maria-Teresa F. and Nelson, Bruce W.}, title = {Fire disturbance in Amazonian blackwater floodplain forests}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {319--328} } |
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Fitzjarrald, D.R., Sakai, R.K., Moraes, O.L.L., Cosme de Oliveira, R., Acevedo, O.C., Czikowsky, M.J. and Beldini, T. | Spatial and temporal rainfall variability near the Amazon-Tapajós confluence | 2008 | Journal of Geophysical Research Vol. 113 |
article | DOI URL |
Abstract: Do the influences of river breezes or other mesoscale effects lead to a systematic river proximity bias in Amazon rainfall data? We analyzed rainfall for a network of 38 rain gauges located near the confluence of the Tapajos and Amazon rivers in the eastern Amazon Basin. Tipping bucket rain gauges worked adequately in the Amazon rainfall regime, but careful field calibration and comparison with collocated conventional rain gauges were essential to incorporate daily totals from our array into regional maps. Stations very near the large rivers miss the afternoon convective rain, as expected if a river breeze promotes subsidence over the river, but paradoxically, this deficiency is more than compensated by additional nocturnal rainfall at these locations. The NOAA Climate Prediction Center (CPC) Morphing technique (CMORPH) passive infrared inferred rainfall data do an adequate job of describing medium scale variability in this region, but some localized breeze effects are not resolved at 0.25 degrees resolution. For areas inland from the rivers, nocturnal rainfall contributes less than half of total precipitation. A large-scale rainfall increase just to the west of Santarem manifests itself locally as a 'tongue' of enhanced rain from along the wide area of open water at the Tapajos-Amazon confluence. The Amazon River breeze circulation affects rainfall more than does the Tapajos breeze, which moves contrary to the predominant wind. East of the riverbank, the effects of the Tapajos breeze extend only a few kilometers inland. Rainfall increases to the north of the Amazon, possibly the result of uplift over elevated terrain. Dry season rainfall increases by up to 30% going away from the Amazon River, as would be expected given breeze-induced subsidence over the river. | |||||
BibTeX:
@article{fitzjarrald_spatial_2008, author = {Fitzjarrald, David R. and Sakai, Ricardo K. and Moraes, Osvaldo L. L. and Cosme de Oliveira, Raimundo and Acevedo, Otávio C. and Czikowsky, Matthew J. and Beldini, Troy}, title = {Spatial and temporal rainfall variability near the Amazon-Tapajós confluence}, journal = {Journal of Geophysical Research}, year = {2008}, volume = {113}, url = {://WOS:000262170400001}, doi = {https://doi.org/10.1029/2007jg000596} } |
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Fisher, R.A., Williams, M., Ruivo, M.d.L., de Costa, A.L. and Meira, P. | Evaluating climatic and soil water controls on evapotranspiration at two Amazonian rainforest sites | 2008 | Agricultural and Forest Meteorology Vol. 148(6-7), pp. 850-861 |
article | DOI URL |
Abstract: Interactions between the biosphere and the atmosphere have profound impacts on the functioning of the Earth system. One of the most important areas of biosphere-atmosphere interaction is the Amazon basin, which plays a key role in the global cycles of carbon, water and energy. The Amazon is vulnerable to climatic change, with increasingly hot and dry conditions expected over the next 50-100 years in some models. The resulting loss of carbon from the Amazon basin has been suggested as a potentially large positive feedback in the climate system. We investigated the differences in atmospheric demand and soil water availability between two sites; Manaus, in central Amazonia, where evapotranspiration was limited in the dry season, and Caxiuana in eastern Amazonia, where it was not. New soil hydraulic data including water release and unsaturated hydraulic conductivity curves were collected at Caxiauna using the instantaneous profile method (IPM), pressure plate analysis and tension infiltrometry. These data were compared to existing data from Manaus. The plant available soil water at the Caxiuana site was 2.1-3.4 times larger than the Manaus site. The hydraulic conductivity curves indicated the existence of a secondary macropore structure at very low tensions (-0.05 kPa to -1 kPa), potentially caused by biogenic macropores, but did not vary with respect to soil water potential between sites. In addition, differences in the climatic severity of the dry season were estimated. The maximum soil water deficit, projected using a simple model of forest water use, was similar between the sites. No difference in climatic severity between sites was found and we conclude that below-ground supply of water, rather than climatic differences, were likely to have caused the contrasting dry season behaviour at the two sites. These findings indicate that, in combination with other factors, heterogeneity in soil water retention capacity may exert strong controls on the spatial variation in forest responses to climatic change. (C) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{fisher_evaluating_2008, author = {Fisher, Rosie A. and Williams, Mathew and Ruivo, Maria de Lourdes and de Costa, Antonio Lola and Meira, Patrick}, title = {Evaluating climatic and soil water controls on evapotranspiration at two Amazonian rainforest sites}, journal = {Agricultural and Forest Meteorology}, year = {2008}, volume = {148}, number = {6-7}, pages = {850--861}, url = {://WOS:000257006200003}, doi = {https://doi.org/10.1016/j.agrformet.2007.12.001} } |
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Fisher, R.A., Williams, M., Do Vale, R.L., Da Costa, A.L. and Meir, P. | Evidence from Amazonian forests is consistent with isohydric control of leaf water potential | 2006 | Plant Cell and Environment Vol. 29(2), pp. 151-165 |
article | DOI URL |
Abstract: Climate modelling studies predict that the rain forests of the Eastern Amazon basin are likely to experience reductions in rainfall of up to 50% over the next 50-100 years. Efforts to predict the effects of changing climate, especially drought stress, on forest gas exchange are currently limited by uncertainty about the mechanism that controls stomatal closure in response to low soil moisture. At a through-fall exclusion experiment in Eastern Amazonia where water was experimentally excluded from the soil, we tested the hypothesis that plants are isohydric, that is, when water is scarce, the stomata act to prevent leaf water potential from dropping below a critical threshold level. We made diurnal measurements of leaf water potential (Psi(l)), stomatal conductance (g(s)), sap flow and stem water potential (Psi(stem)) in the wet and dry seasons. We compared the data with the predictions of the soil-plant-atmosphere (SPA) model, which embeds the isohydric hypothesis within its stomatal conductance algorithm. The model inputs for meteorology, leaf area index (LAI), soil water potential and soil-to-leaf hydraulic resistance (R) were altered between seasons in accordance with measured values. No optimization parameters were used to adjust the model. This 'mechanistic' model of stomatal function was able to explain the individual tree-level seasonal changes in water relations (r(2) = 0.85, 0.90 and 0.58 for Psi(l), sap flow and g(s), respectively). The model indicated that the measured increase in R was the dominant cause of restricted water use during the dry season, resulting in a modelled restriction of sap flow four times greater than that caused by reduced soil water potential. Higher resistance during the dry season resulted from an increase in below-ground resistance (including root and soil-to-root resistance) to water flow. | |||||
BibTeX:
@article{fisher_evidence_2006, author = {Fisher, R. A. and Williams, M. and Do Vale, R. L. and Da Costa, A. L. and Meir, P.}, title = {Evidence from Amazonian forests is consistent with isohydric control of leaf water potential}, journal = {Plant Cell and Environment}, year = {2006}, volume = {29}, number = {2}, pages = {151--165}, url = {://WOS:000234649800001}, doi = {https://doi.org/10.1111/j.1365-3040.2005.01407.x} } |
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Fisher, R.A., Williams, M., Da Costa, A.L., Malhi, Y., Da Costa, R.F., Almeida, S. and Meir, P. | The response of an Eastern Amazonian rain forest to drought stress: results and modelling analyses from a throughfall exclusion experiment | 2007 | Global Change Biology Vol. 13(11), pp. 2361-2378 |
article | DOI URL |
Abstract: Warmer and drier climates over Eastern Amazonia have been predicted as a component of climate change during the next 50-100 years. It remains unclear what effect such changes will have on forest-atmosphere exchange of carbon dioxide (CO2) and water, but the cumulative effect is anticipated to produce climatic feedback at both regional and global scales. To allow more detailed study of forest responses to soil drying, a simulated soil drought or 'throughfall exclusion' (TFE) experiment was established at a rain forest site in Eastern Amazonia, Brazil, for which time-series sap flow and soil moisture data were obtained. The experiment excluded 50% of the throughfall from the soil. Sap flow data from the forest plot experiencing normal rainfall showed no limitation of transpiration throughout the two monitored dry seasons. Conversely, data from the TFE showed large dry season declines in transpiration, with tree water use restricted to 20% of that in the control plot at the peak of both dry seasons. The results were examined to evaluate the paradigm that the restriction on transpiration in the dry season was caused by limitation of soil-to-root water transport, driven by low soil water potential and high soil-to-root hydraulic resistance. This paradigm, embedded in the soil-plant-atmosphere (SPA) model and driven using on-site measurements, provided a good explanation (R-2 textgreater 0.69) of the magnitude and timing of changes in sap flow and soil moisture. This model-data correspondence represents a substantial improvement compared with other ecosystem models of drought stress tested in Amazonia. Inclusion of deeper rooting should lead to lower sensitivity to drought than the majority of existing models. Modelled annual GPP declined by 13-14% in response to the treatment, compared with estimated declines in transpiration of 30-40%. | |||||
BibTeX:
@article{fisher_response_2007, author = {Fisher, R. A. and Williams, M. and Da Costa, A. L. and Malhi, Y. and Da Costa, R. F. and Almeida, S. and Meir, P.}, title = {The response of an Eastern Amazonian rain forest to drought stress: results and modelling analyses from a throughfall exclusion experiment}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {11}, pages = {2361--2378}, url = {://000250262800011}, doi = {https://doi.org/10.1111/j.1365-2486.2007.01417.x} } |
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Fisher, R., McDowell, N., Purves, D., Moorcroft, P., Sitch, S., Cox, P., Huntingford, C., Meir, P. and Woodward, F. | Assessing uncertainties in a second-generation dynamic vegetation model caused by ecological scale limitations | 2010 | New Phytologist Vol. 187(3), pp. 666-681 |
article | DOI URL |
Abstract: *Second-generation Dynamic Global Vegetation Models (DGVMs) have recently been developed that explicitly represent the ecological dynamics of disturbance, vertical competition for light, and succession. Here, we introduce a modified second-generation DGVM and examine how the representation of demographic processes operating at two-dimensional spatial scales not represented by these models can influence predicted community structure, and responses of ecosystems to climate change. *The key demographic processes we investigated were seed advection, seed mixing, sapling survival, competitive exclusion and plant mortality. We varied these parameters in the context of a simulated Amazon rainforest ecosystem containing seven plant functional types (PFTs) that varied along a trade-off surface between growth and the risk of starvation induced mortality. *Varying the five unconstrained parameters generated community structures ranging from monocultures to equal co-dominance of the seven PFTs. When exposed to a climate change scenario, the competing impacts of CO(2) fertilization and increasing plant mortality caused ecosystem biomass to diverge substantially between simulations, with mid-21st century biomass predictions ranging from 1.5 to 27.0 kg C m(-2). *Filtering the results using contemporary observation ranges of biomass, leaf area index (LAI), gross primary productivity (GPP) and net primary productivity (NPP) did not substantially constrain the potential outcomes. We conclude that demographic processes represent a large source of uncertainty in DGVM predictions. | |||||
BibTeX:
@article{fisher_assessing_2010, author = {Fisher, R. and McDowell, N. and Purves, D. and Moorcroft, P. and Sitch, S. and Cox, P. and Huntingford, C. and Meir, P. and Woodward, F.I.}, title = {Assessing uncertainties in a second-generation dynamic vegetation model caused by ecological scale limitations}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {666--681}, note = {Edition: 2010/07/14}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20618912 http://onlinelibrary.wiley.com/store/10.1111/j.1469-8137.2010.03340.x/asset/j.1469-8137.2010.03340.x.pdf?v=1&t=h6hwl928&s=6ec7a161c18b3fa14886a21ddaa1ea2af8b2a959}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03340.x} } |
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Fisher, J.B., Malhi, Y., Bonal, D., Da Rocha, H.R., De Araujo, A.C., Gamo, M., Goulden, M.L., Hirano, T., Huete, A.R., Kondo, H., Kumagai, T., Loescher, H.W., Miller, S., Nobre, A.D., Nouvellon, Y., Oberbauer, S.F., Panuthai, S., Roupsard, O., Saleska, S., Tanaka, K., Tanaka, N., Tu, K.P. and Von Randow, C. | The land-atmosphere water flux in the tropics | 2009 | Global Change Biology Vol. 15(11), pp. 2694-2714 |
article | DOI URL |
Abstract: Tropical vegetation is a major source of global land surface evapotranspiration, and can thus play a major role in global hydrological cycles and global atmospheric circulation. Accurate prediction of tropical evapotranspiration is critical to our understanding of these processes under changing climate. We examined the controls on evapotranspiration in tropical vegetation at 21 pan-tropical eddy covariance sites, conducted a comprehensive and systematic evaluation of 13 evapotranspiration models at these sites, and assessed the ability to scale up model estimates of evapotranspiration for the test region of Amazonia. Net radiation was the strongest determinant of evapotranspiration (mean evaporative fraction was 0.72) and explained 87% of the variance in monthly evapotranspiration across the sites. Vapor pressure deficit was the strongest residual predictor (14%), followed by normalized difference vegetation index (9%), precipitation (6%) and wind speed (4%). The radiation-based evapotranspiration models performed best overall for three reasons: (1) the vegetation was largely decoupled from atmospheric turbulent transfer (calculated from X decoupling factor), especially at the wetter sites; (2) the resistance-based models were hindered by difficulty in consistently characterizing canopy (and stomatal) resistance in the highly diverse vegetation; (3) the temperature-based models inadequately captured the variability in tropical evapotranspiration. We evaluated the potential to predict regional evapotranspiration for one test region: Amazonia. We estimated an Amazonia-wide evapotranspiration of 1370 mm yr(-1), but this value is dependent on assumptions about energy balance closure for the tropical eddy covariance sites; a lower value (1096 mm yr(-1)) is considered in discussion on the use of flux data to validate and interpolate models. | |||||
BibTeX:
@article{fisher_land-atmosphere_2009, author = {Fisher, Joshua B. and Malhi, Yadvinder and Bonal, Damien and Da Rocha, Humberto R. and De Araujo, Alessandro C. and Gamo, Minoru and Goulden, Michael L. and Hirano, Takashi and Huete, Alfredo R. and Kondo, Hiroaki and Kumagai, Tomo'Omi and Loescher, Henry W. and Miller, Scott and Nobre, Antonio D. and Nouvellon, Yann and Oberbauer, Steven F. and Panuthai, Samreong and Roupsard, Olivier and Saleska, Scott and Tanaka, Katsunori and Tanaka, Nobuaki and Tu, Kevin P. and Von Randow, Celso}, title = {The land-atmosphere water flux in the tropics}, journal = {Global Change Biology}, year = {2009}, volume = {15}, number = {11}, pages = {2694--2714}, url = {://WOS:000270662000011}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01813.x} } |
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Fischer, G.R., Costa, M.H., Murta, F.Z., Malhado, A.C., Aguiar, L.J. and Ladle, R.J. | Multi-site land surface model optimization: An exploration of objective functions [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183(15 December 2013), pp. 168-176 |
article | |
BibTeX:
@article{fischer_multi-site_2013, author = {Fischer, Graciela R. and Costa, Marcos H. and Murta, Fabrício Z. and Malhado, Ana C.M. and Aguiar, Leonardo J.G. and Ladle, Richard J.}, title = {Multi-site land surface model optimization: An exploration of objective functions}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, number = {15 December 2013}, pages = {168--176} } |
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Fisch, G., Tota, J., Machado, L.A.T., Dias, M., Lyra, R.F.D., Nobre, C.A., Dolman, A.J. and Gash, J.H.C. | The convective boundary layer over pasture and forest in Amazonia | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 47-59 |
article | DOI URL |
Abstract: The coupling between different types of surface (tropical forest or grass) and the Convective Boundary Layer (CBL) has been investigated using observational (rawinsoundings) data collected over Rondonia in southwest Amazonia. The data reported here support the notion that deforestation may modify the dynamics of the boundary layer, in particular during the dry season. In this period the sensible heat fluxes are very high over pasture, creating a CBL around 550 m deeper compared to that over the forest. The measurements showed the height of the fully developed CBL for pasture to be 1650 m, compared to around 1100 m for forest. During the wet season the height of the CBL is lower than during the dry season and has the same height (around 1000 m) for forest and pasture sites. The CBL over pasture is hotter and drier than over forest during the dry season, but during the wet season the air temperatures and humidities are similar. Comparing the CBL growth during the dry and wet season, there is evidence that the CBL properties over the forest are not dependent on the surface characteristics, but over the pasture they are. | |||||
BibTeX:
@article{fisch_convective_2004, author = {Fisch, G. and Tota, J. and Machado, L. A. T. and Dias, Mafs and Lyra, R. F. D. and Nobre, C. A. and Dolman, A. J. and Gash, J. H. C.}, title = {The convective boundary layer over pasture and forest in Amazonia}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {47--59}, url = {://WOS:000222024700005}, doi = {https://doi.org/10.1007/s00704-004-0043-x} } |
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Fisch, G., Tota, J., Machado, L., Ferrier, B., Dias, M., Dolman, A.J., Halverson, J., Fuentes, J.D. and Ams | Atmospheric boundary layer growth during the LBA/TRMM experiment [BibTeX] |
2000 | 15th Conference on Hydrology, pp. 319-322 | incollection | URL |
BibTeX:
@incollection{fisch_atmospheric_2000, author = {Fisch, G. and Tota, J. and Machado, L. and Ferrier, B. and Dias, Mafs and Dolman, A. J. and Halverson, J. and Fuentes, J. D. and Ams}, title = {Atmospheric boundary layer growth during the LBA/TRMM experiment}, booktitle = {15th Conference on Hydrology}, year = {2000}, pages = {319--322}, url = {://WOS:000168561100094} } |
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Fisch, G. and dos Santos, L.A.R. | Estimates of the height of the boundary layer using SODAR and rawinsoundings in Amazonia | 2008 | Vol. 114th International Symposium for the Advancement of Boundary Layer Remote Sensing, pp. U510-U513 |
incollection | URL |
Abstract: During the LBA campaign in Amazonia 2002, simultaneous measurements were made of the boundary layer using different instruments (rawinsoundings and SODAR). The profiles of potential temperature and humidity were used to estimates the height of the boundary layer using 3 different techniques. The SODAR's measurements did not capture the shallow morning boundary layer observed at the profiles. | |||||
BibTeX:
@incollection{mann_estimates_2008, author = {Fisch, G. and dos Santos, L. A. R.}, title = {Estimates of the height of the boundary layer using SODAR and rawinsoundings in Amazonia}, booktitle = {14th International Symposium for the Advancement of Boundary Layer Remote Sensing}, year = {2008}, volume = {1}, pages = {U510--U513}, url = {://WOS:000256952700065} } |
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Fisch, V., I. F., H. and P.C.M., G. | Variabilidade espacial da chuva durante o experimento LBA/TRMM 1999 na Amazônia [BibTeX] |
2007 | Acta Amazonica Vol. 37(4), pp. 585 - 592 |
article | |
BibTeX:
@article{fisch_variabilidade_2007, author = {Fisch, Vendrame, I. F., Hanaoka, P.C.M., G.}, title = {Variabilidade espacial da chuva durante o experimento LBA/TRMM 1999 na Amazônia}, journal = {Acta Amazonica}, year = {2007}, volume = {37}, number = {4}, pages = {585 -- 592} } |
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Filizola, E.M., Fraizy, P., Souza, R., Guimarães, V., Guyot J.-L., N. and Latrubesse | Was the 2009 flood the most hazardous or the largest ever recorded in the Amazon? [BibTeX] |
2014 | Geomorphology Vol. 215, pp. 99-115 |
article | |
BibTeX:
@article{filizola_was_2014, author = {Filizola, Edgardo M. ; Fraizy, P. ; Souza, R. ; Guimarães, V. ; Guyot, J.-L., Naziano ; Latrubesse}, title = {Was the 2009 flood the most hazardous or the largest ever recorded in the Amazon?}, journal = {Geomorphology}, year = {2014}, volume = {215}, pages = {99--115} } |
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Filizola, N., Beisl, C., Guyot, J.L. and Miranda, F. | O fluxo de matéria em suspensão na Amazônia ocidental como marcador da dinâmica fluvial [BibTeX] |
2012 | (1ed.)Rio Purus: Águas, Território e Sociedade na Amazônia Sul-Ocidental., pp. 89-99 | incollection | |
BibTeX:
@incollection{sousa_junior_o_2012, author = {Filizola, N. and Beisl, C. and Guyot, J. L. and Miranda, F.P.}, title = {O fluxo de matéria em suspensão na Amazônia ocidental como marcador da dinâmica fluvial}, booktitle = {Rio Purus: Águas, Território e Sociedade na Amazônia Sul-Ocidental.}, publisher = {Libri Mundi}, year = {2012}, number = {1ed.}, pages = {89--99} } |
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Figueiredo, R.O., Markewitz, D., Davidson, E.A., Schuler, A.E., Watrin, O.d.S. and Silva, P.d.S. | Land-use effects on the chemical attributes of low-order streams in the eastern Amazon | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115 |
article | DOI URL |
Abstract: Deforestation is altering small catchment hydrobiogeochemistry in the Amazon. To evaluate land use change effects on water chemistry and other measures of water quality, five low-order streams were studied in the eastern Amazon from April 2003 to October 2005. It was hypothesized that 1) cation loads would increase downstream as the area of cleared forest increased, particularly during the wet season, 2) increasing forest to pasture conversion would increase total solute loads, and 3) nitrate concentrations, which are high under mature forest, would decline with conversion to pasture, but would increase with increasing row crop agriculture. The first hypothesis was generally not supported, as there was no consistent observed increase in conductivity or cation concentrations from upstream to downstream. However, elevated wet-season measures of conductivity, alkalinity, and turbidity indicated increased wet season surface runoff of these constituents, with seasonal changes largest in the watersheds that had experienced the most deforestation. The second hypothesis was supported when all data were pooled in a mixed-model analysis such that conductivity declined with increasing percent forest or increased with increasing percent pasture; however, similar correlations with cations were not significant. The third hypothesis was supported, with decreasing nitrate concentrations observed as forest cover declined and pasture cover increased from upstream to downstream positions, except where crops were grown near the stream, which was associated with increased stream nitrate. In addition, stream temperature, dissolved oxygen, and pH were negatively correlated with percent forest cover while sodium, chloride, and turbidity also increased with percent crop cover. Turbidity, temperature, pH, and dissolved oxygen appear to be the simplest and most indicative parameters for detecting effects of land-use change on water quality in this region. | |||||
BibTeX:
@article{figueiredo_land-use_2010, author = {Figueiredo, Ricardo O. and Markewitz, Daniel and Davidson, Eric A. and Schuler, Azeneth E. and Watrin, Orlando dos S. and Silva, Patricio de Souza}, title = {Land-use effects on the chemical attributes of low-order streams in the eastern Amazon}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, url = {://WOS:000282768500003}, doi = {https://doi.org/10.1029/2009jg001200} } |
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Figueira, A., Miller, S., de Sousa, C.D., Menton, M., Maia, A., da Rocha, H. and Goulden, M.L. | Effects of selective logging on tropical forest tree growth | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: We combined measurements of tree growth and carbon dioxide exchange to investigate the effects of selective logging on the Aboveground Live Biomass (AGLB) of a tropical rain forest in the Amazon. Most of the measurements began at least 10 months before logging and continued at least 36 months after logging. The logging removed similar to 15% of the trees with Diameter at Breast Height (DBH) greater than 35 cm, which resulted in an instantaneous 10% reduction in AGLB. Both wood production and mortality increased following logging, while Gross Primary Production (GPP) was unchanged. The ratio of wood production to GPP (the wood Carbon Use Efficiency or wood CUE) more than doubled following logging. Small trees (10 cm textless DBH textless 35 cm) accounted for most of the enhanced wood production. Medium trees (35 cm textless DBH textless 55 cm) that were within 30 m of canopy gaps created by the logging also showed increased growth. The patterns of enhanced growth are most consistent with logging-induced increases in light availability. The AGLB continued to decline over the study, as mortality outpaced wood production. Wood CUE and mortality remained elevated throughout the 3 years of postlogging measurements. The future trajectory of AGLB and the forest's carbon balance are uncertain, and will depend on how long it takes for heterotrophic respiration, mortality, and CUE to return to prelogging levels. | |||||
BibTeX:
@article{figueira_effects_2008, author = {Figueira, A.M.S. and Miller, S.D. and de Sousa, C.A. D. and Menton, M.C. and Maia, A.R. and da Rocha, H.R. and Goulden, M. L.}, title = {Effects of selective logging on tropical forest tree growth}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000259804100001}, doi = {https://doi.org/10.1029/2007jg000577} } |
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Ferreira-Ferreira, J., T.S.F., S., Streher, A., Alfonso, A., Furtado, L., Forsberg, B., Valsecchi, J., Queiroz, H. and Novo, E. | Combining ALOS/PALSAR derived vegetation structure and inundation patterns to characterize major vegetation types in the Mamirauá Sustainable Development Reserve, Central Amazon floodplain, Brazil [BibTeX] |
2015 | Wetlands Ecology and Management Vol. 23, pp. 41-59 |
article | |
BibTeX:
@article{ferreira-ferreira_combining_2015, author = {Ferreira-Ferreira, J.S. and T.S.F., Silva and Streher, A.S. and Alfonso, A.G. and Furtado, L.F.A. and Forsberg, B.R. and Valsecchi, J. and Queiroz, H.L. and Novo, E.M.L.M.}, title = {Combining ALOS/PALSAR derived vegetation structure and inundation patterns to characterize major vegetation types in the Mamirauá Sustainable Development Reserve, Central Amazon floodplain, Brazil}, journal = {Wetlands Ecology and Management}, year = {2015}, volume = {23}, pages = {41--59} } |
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Ferreira, S.J.F., Pinel, S., Ríos-Villamizar, E.A., Miranda, S.Á.F., Pascoaloto, D., Vital, A.R.T., Monteiro, M.T.F., da Silva, M.d.S.R., da Cunha, T.R.B., dos Santos, A.S., Bender, S. and da Cunha, H.B. | Impact of rapid urbanization on stream water quality in the Brazilian Amazon | 2021 | Environmental Earth Sciences Vol. 80(8), pp. 316 |
article | DOI URL |
Abstract: The most populous city of the world’s largest watershed (Manaus, Amazon Basin, Brazil) is experiencing an extensive urban expansion since the early 1970s, with an attendant cost in environmental degradation. The upland area of the Manaus municipality is characterized by several streams. In this work, we aim to gradually measure the anthropogenic effect on water quality: we monitored three streams flowing over three zones: a preserved (where the streams take source), a peri-urban (where rural and leisure activities occur), and an urban area. From June 2013 to May 2015, we characterized the water quality of these streams. Statistical analyses reveal peri-urban activity does not significantly impact the water quality. Indeed, when the disturbance remains space-, time- and intensity-limited, the streams have the capacity to assimilate the anthropogenic pollution. However, looking at a seasonal finer scale, peri-urban activity slightly affects the natural pattern of water quality, but these changes remain moderated when compared to the original pattern of water quality. Over urban area, the water quality presents significant higher alkalinity, mineralization, turbidity, suspended material, biochemical and chemical oxygen demands, and lower acidity and dissolved oxygen. These alterations originate with sewage deficiency, presence of landfill sites, enhanced leaching of upturned soil and domestic waste. The natural seasonal patterns of water quality are totally disturbed (inversion, intensification) in the urban area. During the wet season, enhanced rainfall in conjunction with human activity generates local seasonal processes of dilution (e.g. negative anomalies for most of the dissolved elements) and concentration (positive Mg and Fe anomalies). The latter can be linked with enhanced leaching during the rainy period (positive Mg and Fe anomalies) and nitrification activity in the urban area (positive NO3 and negative NH4 anomalies). | |||||
BibTeX:
@article{ferreira_impact_2021, author = {Ferreira, Sávio José Filgueiras and Pinel, Sebastien and Ríos-Villamizar, Eduardo Antonio and Miranda, Sebastião Átila Fonseca and Pascoaloto, Domitila and Vital, Ana Rosa Tundis and Monteiro, Maria Terezinha Ferreira and da Silva, Maria do Socorro Rocha and da Cunha, Thaís Rivera Brandão and dos Santos, Almir Salgado and Bender, Steffen and da Cunha, Hillândia Brandão}, title = {Impact of rapid urbanization on stream water quality in the Brazilian Amazon}, journal = {Environmental Earth Sciences}, year = {2021}, volume = {80}, number = {8}, pages = {316}, url = {https://doi.org/10.1007/s12665-021-09621-7}, doi = {https://doi.org/10.1007/s12665-021-09621-7} } |
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Ferreira, S.J.F., Luizao, F.J., Ross, S.M., Biot, Y. and Mello-Ivo, W.M.P. | Soil water storage in an upland forest after selective logging in Central Amazonia | 2004 | Revista Brasileira De Ciencia Do Solo Vol. 28(1), pp. 59-66 |
article | URL |
Abstract: Soil water storage of Central Amazonian soil profiles in upland forest plots subjected to selective logging (in average, 8 trees or 34,3 m(3) of timber per hectare were removed) was measured in four layers, down to a depth of 70 cm. The study lasted 27-months and was divided in two phases: measurements were carried out nearly every week during the first 15 months; in the following year, five intensive periods of measurements were performed. Five damage levels were compared: (a) control (undisturbed forest plot); (b) centre of the clearing/ gap; (c) edge of the gap; (d) edge of the remaining forest; and (e) remaining forest. The lowest values for water storage were found in the control (296 +/- 19.1 mm), while the highest were observed (333 +/- 25.8 mm) in the centre of the gap, during the dry period. In the older gaps (7.5-8.5 year old), soil water storage was similar to the remaining and the control forest, indicating a recovery of hydric soil properties to nearly the levels, prior to selective logging. | |||||
BibTeX:
@article{ferreira_soil_2004, author = {Ferreira, S. J. F. and Luizao, F. J. and Ross, S. M. and Biot, Y. and Mello-Ivo, W. M. P.}, title = {Soil water storage in an upland forest after selective logging in Central Amazonia}, journal = {Revista Brasileira De Ciencia Do Solo}, year = {2004}, volume = {28}, number = {1}, pages = {59--66}, url = {://WOS:000220212100006} } |
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Ferreira, S. and Luizão, F. | Propriedades físicas do solo após extração seletiva de madeira na Amazônia Central. [BibTeX] |
2002 | Acta Amazonica Vol. 32, pp. 449-466 |
article | |
BibTeX:
@article{ferreira_propriedades_2002, author = {Ferreira, S.J.F. and Luizão, F.J.}, title = {Propriedades físicas do solo após extração seletiva de madeira na Amazônia Central.}, journal = {Acta Amazonica}, year = {2002}, volume = {32}, pages = {449--466} } |
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Ferreira Luizão, F., Miranda, S. and Silva M.S.R. & Vital, A.S. | Nutrientes na solução do solo em floresta de terra firme na Amazônia Central submetida à extração seletiva de madeira [BibTeX] |
2006 | Acta Amazônica Vol. 36, pp. 59-68 |
article | |
BibTeX:
@article{ferreira_nutrientes_2006, author = {Ferreira, Luizão, F.J.; Miranda, S.Á.F.; Silva, M.S.R. & Vital, A.R.T., S.J.F.}, title = {Nutrientes na solução do solo em floresta de terra firme na Amazônia Central submetida à extração seletiva de madeira}, journal = {Acta Amazônica}, year = {2006}, volume = {36}, pages = {59--68} } |
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Ferreira Luizão, F.&.D.R.S. | Precipitação interna e interceptação da chuva em floresta de terra firme submetida à extração seletiva de madeira na Amazônia Central. [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 55-62 |
article | |
BibTeX:
@article{ferreira_precipitacao_2005, author = {Ferreira, Luizão, F.J. & Dallarosa, R.L.G., S.J.F.}, title = {Precipitação interna e interceptação da chuva em floresta de terra firme submetida à extração seletiva de madeira na Amazônia Central.}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {55--62} } |
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Ferreira Crestana, S. and Luizão F.J. & Miranda, S.S. | Nutrientes no solo em floresta de terra firme cortada seletivamente na Amazônia Central. [BibTeX] |
2001 | Acta Amazonica Vol. 31, pp. 381-396 |
article | |
BibTeX:
@article{ferreira_nutrientes_2001, author = {Ferreira, Crestana, S.; Luizão, F.J. & Miranda, S.A.F., S.J.F.}, title = {Nutrientes no solo em floresta de terra firme cortada seletivamente na Amazônia Central.}, journal = {Acta Amazonica}, year = {2001}, volume = {31}, pages = {381--396} } |
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Ferreira, P.R.G., Matias, A.C.C., de Albuquerque, S.D., de Abreu, A.C., Lages, A.d.S., Miranda, S.Á.F., Ferreira, S.J.F. and da Silva, M.L. | Correlação Linear entre Fosfato e Potássio em Igarapés da Bacia Hidrográfica do Educandos, Manaus-AM | 5 | Revista Contemporânea Vol. 3(5), pp. 3507-3520 |
article | DOI URL |
Abstract: <p>Fósforo (P) e potássio (K) são macronutrientes essenciais às plantas e aos animais. Em ambientes aquáticos contaminados por esgotos domésticos e industriais, esses nutrientes podem causar sérios problemas. O fosfato (P-PO<sub>4</sub><sup>3-</sup>), na forma solúvel, representa uma fonte interna de fósforo para o crescimento de algas, e a ingestão de água com excesso de K pode provocar graves efeitos laxantes. Dessa forma, o presente trabalho tem como objetivo avaliar correlação linear entre esses dois parâmetros usando o método de correlação de Pearson (R) em amostras de água coletadas na Bacia Hidrográfica do Educandos (Manaus-AM). Em estudos de monitoramento, esse conhecimento se faz importante para estabelecer as principais variáveis que influenciam nos níveis de contaminação dos igarapés na Bacia Hidrográfica do Educandos.</p> | |||||
BibTeX:
@article{ferreira_correlacao_5, author = {Ferreira, Paulo Renan Gomes and Matias, Angélica Chrystina Cruz and de Albuquerque, Sâmia Dourado and de Abreu, Aretusa Cetauro and Lages, Anderson da Silva and Miranda, Sebastião Átila Fonseca and Ferreira, Sávio José Filgueiras and da Silva, Márcio Luiz}, title = {Correlação Linear entre Fosfato e Potássio em Igarapés da Bacia Hidrográfica do Educandos, Manaus-AM}, journal = {Revista Contemporânea}, year = {5}, volume = {3}, number = {5}, pages = {3507--3520}, url = {https://ojs.revistacontemporanea.com/ojs/index.php/home/article/view/685}, doi = {https://doi.org/10.56083/RCV3N5-006} } |
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Ferreira, N.J., Correia, A.A. and Ramirez, M.C.V. | Synoptic scale features of the tropospheric circulation over tropical South America during the WETAMC TRMM/LBA experiment | 2004 | Atmosfera Vol. 17(1), pp. 13-30 |
article | URL |
Abstract: This paper analyzes the synoptic scale features of the upper and lower level tropospheric circulation over tropical South America during the first Atmospheric Mesoscale Campaign in the Wet Season (WETAMC) of the Large Scale Biosphere - Atmosphere Experiment in Amazonia (LBA). This campaign occurred in January and February, 1999 and concomitantly with the validation of the Tropical Rainfall Measuring Mission (TRMM) satellite over Brazil. National Centers for Environmental Predictions (NCEP) grid point data were used to analyze the winds and its associated divergence fields and define the prevailing patterns of the tropospheric circulation in that region. TRMM images were used to depict the rain patterns. The results show at least four distinct patterns in the upper air winds fields during the WETAMC-TRMM/LBA, involving mainly the Bolivian anticyclonic circulation and cyclonic vortices in the vicinity of Northeast Brazil. The results also suggest that, in general, the convective activity over vast areas of South America is dynamically supported by upper level divergence. Two out of a total of six vortices were observed to have anomalous displacements into the Amazonia during the study period. At lower levels, the South Atlantic Convergence Zone (SACZ), except for the first half of January, was not active but equatorward incursions of midlatitude frontal systems disturbed the convective activy in the Southwestern Amazon basin. Besides, during the period of the study, the low-level moisture divergence as derived from NCEP data does not show convergence where the TRMM rain field clearly reveals the existence of precipitation areas. | |||||
BibTeX:
@article{ferreira_synoptic_2004, author = {Ferreira, N. J. and Correia, A. A. and Ramirez, M. C. V.}, title = {Synoptic scale features of the tropospheric circulation over tropical South America during the WETAMC TRMM/LBA experiment}, journal = {Atmosfera}, year = {2004}, volume = {17}, number = {1}, pages = {13--30}, url = {://WOS:000189109300002} } |
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Ferreira Sanches, M.&.S.-D.M.N. | Composição da Zona de Convergência do Atlântico Sul em períodos de El Niño e La Niña. [BibTeX] |
2004 | Revista Brasileira de Meteorologia Vol. 19, pp. 89-98 |
article | |
BibTeX:
@article{ferreira_composicao_2004, author = {Ferreira, Sanches, M. & Silva-Dias, M.A.F., N.J.}, title = {Composição da Zona de Convergência do Atlântico Sul em períodos de El Niño e La Niña.}, journal = {Revista Brasileira de Meteorologia}, year = {2004}, volume = {19}, pages = {89--98} } |
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Ferreira, N.C., Ferreira, L.G., Huete, A.R. and Ferreira, M.E. | An operational deforestation mapping system using MODIS data and spatial context analysis | 2007 | International Journal of Remote Sensing Vol. 28(1-2), pp. 47-62 |
article | DOI URL |
Abstract: The Brazilian Amazon has the world's highest absolute rate of forest loss, currently averaging nearly 2 million hectares per year. In this study, we present a near-real-time automated deforestation mapping system for the Brazilian Amazon based on the analysis of spatial context information and MODIS Vegetation Index products and implemented on an ArcGIS 9.0 platform. This system, already validated and operational, was developed as part of the "Integrated Warning Deforestation System for the Amazon" (SIAD), an initiative of the Brazilian government within the scope of the Amazon Protection System (SIPAM), which also comprises: (1) a spatial information module, aimed at the assessment of the causes and impacts of the deforested areas: (2) a prediction module, indicative of deforestation trends; and (3) a data and information gateway based on map server technology. | |||||
BibTeX:
@article{ferreira_operational_2007, author = {Ferreira, N. C. and Ferreira, L. G. and Huete, A. R. and Ferreira, M. E.}, title = {An operational deforestation mapping system using MODIS data and spatial context analysis}, journal = {International Journal of Remote Sensing}, year = {2007}, volume = {28}, number = {1-2}, pages = {47--62}, url = {://WOS:000244093200005}, doi = {https://doi.org/10.1080/01431160600835861} } |
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Ferreira, N.C., Ferreira, L.G. and Huete, A.R. | Assessing the response of the MODIS vegetation indices to landscape disturbance in the forested areas of the legal Brazilian Amazon | 2010 | International Journal of Remote Sensing Vol. 31(3), pp. 745-759 |
article | DOI URL |
Abstract: In this study we assessed the impacts of forest fragmentation on the Amazon landscape using remote sensing techniques. Landscape disturbance, obtained for an area of approximately 3.5 x 10(6) km(2) through simple spatial metrics (i.e. number of fragments, mean fragment area and border size) and principal component transformation were then compared to the MODIS (Moderate Resolution Imaging Spectroradiometer) NDVI (Normalized Difference Vegetation Index) and EVI (Enhanced Vegetation Index) seasonal responses. As expected, higher disturbance values prevail in the southern border of the Amazon, near the intensively converted deforestation arc, and close to the major roads. NDVI seasonal responses more closely follow human-induced patterns, i.e. forest remnants from areas more intensively converted were associated with higher NDVI seasonal values. The significant correlation between NDVI seasonal responses and landscape disturbances were corroborated through analysis of geographically weighted regression (GWR) parameters and predictions. On the other hand, EVI seasonal responses were more complex with significant variations found over intact, less fragmented forest patches, thus restricting its utility to assess landscape disturbance. Although further research is needed, our results suggest that the degree of fragmentation of the forest remnants can be remotely sensed with MODIS vegetation indices. Thus, it may become possible to upscale field-based data on overall canopy condition and fragmentation status for basin-wide extrapolations. | |||||
BibTeX:
@article{ferreira_assessing_2010, author = {Ferreira, N. C. and Ferreira, L. G. and Huete, A. R.}, title = {Assessing the response of the MODIS vegetation indices to landscape disturbance in the forested areas of the legal Brazilian Amazon}, journal = {International Journal of Remote Sensing}, year = {2010}, volume = {31}, number = {3}, pages = {745--759}, url = {://WOS:000275877100012}, doi = {https://doi.org/10.1080/01431160902897817} } |
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Ferreira, M.E., Ferreira, L.G., Sano, E.E. and Shimabukuro, Y.E. | Spectral linear mixture modelling approaches for land cover mapping of tropical savanna areas in Brazil | 2007 | International Journal of Remote Sensing Vol. 28(1-2), pp. 413-429 |
article | DOI URL |
Abstract: It is estimated that approximately 60% of the natural vegetative cover of the Brazilian savanna, locally known as the Cerrado and the second largest biome in South America, have already been converted. Despite this rapid conversion pace, there have only been limited attempts to operationally monitor this major farming frontier with remote sensing data. In this study, we evaluated the performance of spectral linear mixture models (SLMM) for the mapping of the major Cerrado physiognomies. Two SLMMs were considered: a general model, comprising the vegetation, soil and shade components, and a specific model, restricted to the 'true' Cerrado physiognomies. We also considered the potential effects of atmospheric contamination, and the influence of endmember sources on the fraction images derived from the general and specific models, respectively. The general model, apparently resistant to the atmosphere with respect to land cover discrimination, primarily enhanced forested domains and non-vegetated targets (water bodies and bare soils). By contrast, the specific model, regardless of the endmember source, significantly distinguished the major Cerrado physiognomies. Such contrasting and complementary behavior suggests a potential synergism between the general and specific models for the mapping and monitoring of a complex environment such as the Cerrado biome. | |||||
BibTeX:
@article{ferreira_spectral_2007, author = {Ferreira, M. E. and Ferreira, L. G. and Sano, E. E. and Shimabukuro, Y. E.}, title = {Spectral linear mixture modelling approaches for land cover mapping of tropical savanna areas in Brazil}, journal = {International Journal of Remote Sensing}, year = {2007}, volume = {28}, number = {1-2}, pages = {413--429}, url = {://WOS:000244093200024}, doi = {https://doi.org/10.1080/01431160500181507} } |
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Ferreira, L.V., Cunha, D.A., Parolin, P. and Costa, A.C.L. | Impacts of experimental drought on community structure and floristic composition of tree saplings in a lowland tropical rainforest in Eastern Amazonia [BibTeX] |
2016 | Boletim do Museu Paraense Emílio Goeldi Ciências Naturais Vol. 11(3), pp. 351-363 |
article | |
BibTeX:
@article{ferreira_impacts_2016, author = {Ferreira, L. V. and Cunha, D. A. and Parolin, P. and Costa, A. C. L.}, title = {Impacts of experimental drought on community structure and floristic composition of tree saplings in a lowland tropical rainforest in Eastern Amazonia}, journal = {Boletim do Museu Paraense Emílio Goeldi Ciências Naturais}, year = {2016}, volume = {11}, number = {3}, pages = {351--363} } |
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Ferreira, L.G., Yoshioka, H., Huete, Y. and Sano, E.E. | Optical characterization of the Brazilian savanna physiognomies for improved land cover monitoring of the cerrado biome: preliminary assessments from an airborne campaign over an LBA core site | 2004 | Journal of Arid Environments Vol. 56(3), pp. 425-447 |
article | DOI URL |
Abstract: It is estimated that approximately 40% of the Cerrado, the second largest biome in South America, have been already converted. In this study, situated within the scope of the Large Scale Biosphere-Atmosphere Experiment in Amazonia project (LBA), we conducted a wet season ground and airborne campaign over the Brasilia National Park (BNP), the largest LBA core site in the Cerrado biome, to measure the optical and biophysical properties of the major Cerrado land cover types. We investigated land cover discrimination through the analyses of fine resolution spectra, convolved spectra (MODIS bandpasses), and vegetation indices-the normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI). At these three data levels, three major physiognomic domains (herbaceous, woody, and forested) could be readily identified, and the amount of data correctly classified into the five major land cover types found at BNP were 91% (full spectra), 78% (red and NIR), 75% (NDVI), and 71% (EVI). A synergism between the NDVI and EVI was also evident, and together, these two indices were capable of correctly classifying 82% of the total data set. Our results indicate the possibility of utilizing the MODIS NDVI and EVI images for operational land cover assessments in the Cerrado region. (C) 2003 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{ferreira_optical_2004, author = {Ferreira, L. G. and Yoshioka, H. and Huete, Y. and Sano, E. E.}, title = {Optical characterization of the Brazilian savanna physiognomies for improved land cover monitoring of the cerrado biome: preliminary assessments from an airborne campaign over an LBA core site}, journal = {Journal of Arid Environments}, year = {2004}, volume = {56}, number = {3}, pages = {425--447}, url = {://WOS:000187882600004}, doi = {https://doi.org/10.1016/s0140-1963(03)00068-5} } |
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Ferreira, L.G., Yoshioka, H., Huete, A. and Sano, E.E. | Seasonal landscape and spectral vegetation index dynamics in the Brazilian Cerrado: An analysis within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 534-550 |
article | DOI URL |
Abstract: The Brazilian Cerrado biome comprises a vertically structured mosaic of grassland, shrubland, and woodland physiognomies with distinct phenology patterns. In this study, we investigated the utility of spectral vegetation indices in differentiating these physiognomies and in monitoring their seasonal dynamics. We obtained high spectral resolution reflectances, during the 2000 wet and dry seasons, over the major Cerrado types at Brasilia National Park (BNP) using the light aircraft-based Modland Quick Airborne Looks (MQUALS) package, consisting of a spectroradiometer and digital camera. Site-intensive biophysical and canopy structural measurements were made simultaneously at each of the Cerrado types including Cerrado grassland, shrub Cerrado, wooded Cerrado, Cerrado woodland, and gallery forest. We analyzed the spectral reflectance signatures, their first derivative analogs, and convolved spectral vegetation indices (VI) over all the Cerrado physiognomies. The high spectral resolution data were convolved to the MODIS, AVHRR, and ETM(+) bandpasses and converted to the normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI) to simulate their respective sensors. Dry and wet season comparisons of the measured biophysical attributes were made with the reflectance and VI data for the different Cerrado physiognomies. We found that three major domains of Cerrado could be distinguished with the dry and wet season spectral signatures and vegetation indices. The EVI showed a higher sensitivity to seasonality than the NDVI; however, both indices displayed seasonal variations that were approximately one-half that found with the measured landscape green cover dynamics. Inter-sensor comparisons of seasonal dynamics, based on spectral bandpass properties, revealed the ETM(+)-simulated VIs had the best seasonal discrimination capability, followed by MODIS and AVHRR. Differences between sensor bandpass-derived VI values, however, varied with Cerrado type and between dry and wet seasons, indicating the need for inter-sensor VI translation equations for effective multi-sensor applications. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{ferreira_seasonal_2003, author = {Ferreira, L. G. and Yoshioka, H. and Huete, A. and Sano, E. E.}, title = {Seasonal landscape and spectral vegetation index dynamics in the Brazilian Cerrado: An analysis within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {534--550}, url = {://WOS:000186827400012}, doi = {https://doi.org/10.1016/j.rse.2002.09.003} } |
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Ferreira, L.G. and Huete, A.R. | Assessing the seasonal dynamics of the Brazilian Cerrado vegetation through the use of spectral vegetation indices | 2004 | International Journal of Remote Sensing Vol. 25(10), pp. 1837-1860 |
article | DOI URL |
Abstract: In this study, the response of vegetation indices (VIs) to the seasonal patterns and spatial distribution of the major vegetation types encountered in the Brazilian Cerrado was investigated. The Cerrado represents the second largest biome in South America and is the most severely threatened biome as a result of rapid land conversions. Our goal was to assess the capability of VIs to effectively monitor the Cerrado and to discriminate among the major types of Cerrado vegetation. A full hydrologic year (1995) of composited AVHRR, local area coverage (LAC) data was converted to Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI) values. Temporal extracts were then made over the major Cerrado vegetation communities. Both the NDVI and SAVI temporal profiles corresponded well to the phenological patterns of the natural and converted vegetation formations and depicted three major categories encompassing the savanna formations and pasture sites, the forested areas, and the agricultural crops. Secondary differences in the NDVI and SAVI temporal responses were found to be related to their unique interactions with sun-sensor viewing geometries. An assessment of the functional behaviour of the VIs confirmed SAVI responds primarily to NIR variations, while the NDVI showed a strong dependence on the red reflectance. Based on these results, we expect operational use of the MODIS Enhanced Vegetation Index (EVI) to provide improved discrimination and monitoring capability of the significant Cerrado vegetation types. | |||||
BibTeX:
@article{ferreira_assessing_2004, author = {Ferreira, L. G. and Huete, A. R.}, title = {Assessing the seasonal dynamics of the Brazilian Cerrado vegetation through the use of spectral vegetation indices}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {10}, pages = {1837--1860}, url = {://WOS:000220718500004}, doi = {https://doi.org/10.1080/0143116031000101530} } |
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Ferreira, J.N., Bustamante, M.M.d.C. and Davidson, E.A. | Linking woody species diversity with plant available water at a landscape scale in a Brazilian savanna | 2009 | Journal of Vegetation Science Vol. 20(5), pp. 826-835 |
article | URL |
Abstract: Question: How is the diversity of woody species in a seasonally dry savanna related to plant available water (PAW)? Location: Savannas in central Brazil. Methods: Two-dimensional soil resistivity profiles to 10-m depth previously measured along three 10 m x 275 m replicate transects revealed differences in belowground water resources among and within transects: (1) driest/most heterogeneous; (2) wettest/least heterogeneous; and (3) PAW-intermediate. All woody plants along these transects were identified to species, and height and basal circumference measured. Species diversity was evaluated for the whole transect (total diversity), 100-m(2) plots (alpha-diversity) and dissimilarity among 100-m(2) plots within transects (beta-diversity). Correlation analyses were conducted between PAW and vegetation variables at the 100-m(2) scale. Results: The driest/most heterogeneous transect had the lowest total species diversity, while the wettest/least heterogeneous transect showed the lowest beta-diversity. Floristic variation was correlated with PAW in all transects. In the most heterogeneous transect, species density was positively correlated with PAW in the 0-400 cm soil layer. Evenness and Simpson's diversity were negatively correlated with PAW in the 700-1000 cm soil layer. Conclusion: Woody species diversity was related to PAW at a fine spatial scale. Abundant PAW in the top 4 m of soil may favour many species and increase species total diversity. Conversely, abundant PAW at depth may result in lower evenness and total diversity, probably because the few species adapted to obtaining deep soil water can become dominant. Environmental changes altering soil water availability and partitioning in soil layers could affect the diversity of woody plants in this savanna. | |||||
BibTeX:
@article{ferreira_linking_2009, author = {Ferreira, Joice N. and Bustamante, Mercedes M. da C. and Davidson, Eric A.}, title = {Linking woody species diversity with plant available water at a landscape scale in a Brazilian savanna}, journal = {Journal of Vegetation Science}, year = {2009}, volume = {20}, number = {5}, pages = {826--835}, url = {://WOS:000270031300005} } |
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Ferreira, J.N., Bustamante, M., Garcia-Montiel, D.C., Caylor, K.K. and Davidson, E.A. | Spatial variation in vegetation structure coupled to plant available water determined by two-dimensional soil resistivity profiling in a Brazilian savanna | 2007 | Oecologia Vol. 153(2), pp. 417-430 |
article | DOI URL |
Abstract: Tropical savannas commonly exhibit large spatial heterogeneity in vegetation structure. Fine-scale patterns of soil moisture, particularly in the deeper soil layers, have not been well investigated as factors possibly influencing vegetation patterns in savannas. Here we investigate the role of soil water availability and heterogeneity related to vegetation structure in an area of the Brazilian savanna (Cerrado). Our objective was to determine whether horizontal spatial variations of soil water are coupled with patterns of vegetation structure across tens of meters. We applied a novel methodological approach to convert soil electrical resistivity measurements along three 275-m transects to volumetric water content and then to estimates of plant available water (PAW). Structural attributes of the woody vegetation, including plant position, height, basal circumference, crown dimensions, and leaf area index, were surveyed within twenty-two 100-m(2) plots along the same transects, where no obvious vegetation gradients had been apparent. Spatial heterogeneity was evaluated through measurements of spatial autocorrelation in both PAW and vegetation structure. Comparisons with null models suggest that plants were randomly distributed over the transect with the greatest mean PAW and lowest PAW heterogeneity, and clustered in the driest and most heterogeneous transect. Plant density was positively related with PAW in the top 4 m of soil. The density-dependent vegetation attributes that are related to plot biomass, such as sum of tree heights per plot, exhibited spatial variation patterns that were remarkably similar to spatial variation of PAW in the top 4 m of soil. For PAW below 4 m depth, mean vegetation attributes, such as mean height, were negatively correlated with PAW, suggesting greater water uptake from the deep soil by plants of larger stature. These results are consistent with PAW heterogeneity being an important structuring factor in the plant distribution at the scale of tens of meters in this ecosystem. | |||||
BibTeX:
@article{ferreira_spatial_2007, author = {Ferreira, Joice N. and Bustamante, Mercedes and Garcia-Montiel, Diana C. and Caylor, Kelly K. and Davidson, Eric A.}, title = {Spatial variation in vegetation structure coupled to plant available water determined by two-dimensional soil resistivity profiling in a Brazilian savanna}, journal = {Oecologia}, year = {2007}, volume = {153}, number = {2}, pages = {417--430}, note = {Edition: 2007/05/05}, url = {://WOS:000249150200021}, doi = {https://doi.org/10.1007/s00442-007-0747-6} } |
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Ferreira, J., Lennox, G.D., Gardner, T.A., Thomson, J.R., Berenguer, E., Lees, A.C., Nally, R.M., Aragão, L.E.O.C., Ferraz, S.F.B., Louzada, J., Moura, N.G., Oliveira, V.H.F., Pardini, R., Solar, R.R.C., Vieira, I.C.G. and Barlow, J. | Carbon-focused conservation may fail to protect the most biodiverse tropical forests [BibTeX] |
2018 | Nature Climate Change | article | DOI |
BibTeX:
@article{ferreira_carbon-focused_2018, author = {Ferreira, Joice and Lennox, Gareth D. and Gardner, Toby A. and Thomson, James R. and Berenguer, Erika and Lees, Alexander C. and Nally, Ralph Mac and Aragão, Luiz E. O. C. and Ferraz, Silvio F. B. and Louzada, Julio and Moura, Nárgila G. and Oliveira, Victor H. F. and Pardini, Renata and Solar, Ricardo R. C. and Vieira, Ima C. G. and Barlow, Jos}, title = {Carbon-focused conservation may fail to protect the most biodiverse tropical forests}, journal = {Nature Climate Change}, year = {2018}, doi = {https://doi.org/10.1038/s41558-018-0225-7} } |
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Ferraz, S.F.D., Vettorazzi, C.A., Theobald, D.M. and Ballester, M.V.R. | Landscape dynamics of Amazonian deforestation between 1984 and 2002 in central Rondonia, Brazil: assessment and future scenarios | 2005 | Forest Ecology and Management Vol. 204(1), pp. 67-83 |
article | DOI URL |
Abstract: Central Rondonia is one of the most deforested regions in the Brazilian Amazon and contains areas at different stages of degradation forming a gradient from mature forest to highly urbanized and built-up areas. Regional data from satellite imagery are available from the 1980s, but apart from studies that quantify deforestation, the broad-scale landscape dynamics of Rondonia have not been examined well. This paper assesses the landscape changes between 1984 and 2002 in a watershed located in the central region of the state of Rondonia, Brazil, which has undergone systematic and rapid deforestation due to introduction of pasture that began in the 1970s. Bi-annual Landsat TM/ETM+ images from 1984 to 2002 were classified into three broad land cover types: mature forest, secondary forest, and pasture, resulting in a time series of land-use/land-cover maps. Landscape changes were evaluated by computing a cross tabulation between years, transition rates, and landscape metrics related to size, density, connectivity, configuration, and deforested patches distribution related to patch size and spatial proximity to roads and old pastures. Transition probability functions were fitted to the temporal series to predict land-use changes for the next 10 years, for three different scenarios: (1) continued land-use change; (2) eliminating clear-cutting and selective logging; and (3) eliminating clear-cutting, selective logging, and secondary vegetation clearing. Current land-use transitions cannot be sustained beyond the next 10-15 years. A more sustainable scenario for the region requires a major reduction of deforestation activities, implementing the "permanent preservation area" policy along riversides, and controlling land-use transitions at balanced levels. We recommend that forest managers in regions facing similar deforestation pressures should strive to maintain at least 35% mature or primary forest, because landscape fragmentation proceeds rapidly below this critical threshold. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{ferraz_landscape_2005, author = {Ferraz, S. F. D. and Vettorazzi, C. A. and Theobald, D. M. and Ballester, M. V. R.}, title = {Landscape dynamics of Amazonian deforestation between 1984 and 2002 in central Rondonia, Brazil: assessment and future scenarios}, journal = {Forest Ecology and Management}, year = {2005}, volume = {204}, number = {1}, pages = {67--83}, url = {://WOS:000226262200006}, doi = {https://doi.org/10.1016/j.foreco.2004.07.073} } |
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Ferraz, R., Guimarães, G., Reis, T., Higuchi N., J. and Bastos | A floresta e o solo [BibTeX] |
2012 | (2ed.)A Floresta Amazônica e suas múltiplas Dimensões: Uma proposta de educação ambiental, pp. 101-122 | incollection | |
BibTeX:
@incollection{higuchi_floresta_2012, author = {Ferraz, R.P.; Guimarães, G.P.; Reis, T.S.; Higuchi, N., J.B.S.; Bastos}, title = {A floresta e o solo}, booktitle = {A Floresta Amazônica e suas múltiplas Dimensões: Uma proposta de educação ambiental}, publisher = {INPA/FAPEAM/CNPq/ INCT}, year = {2012}, number = {2ed.}, pages = {101--122} } |
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Ferraz, J.B., Luizão, F.J., Zanchi, F.B., Costa, H.S., Quesada, C.A., Gonçalves, J.F., Ferreira, M.J., Rodrigues, J.V., Coral, S.C., Florentino, A.P.P., Pereira, A.R., Paiva, R., Martins, D.L., Mendonza, E.M., Lugli, L.F., Campos, M.C., Santos, S.d., Pereira, F.E.L., Barbosa, L.d.A., Ferreira, D.M.M., Jordão, W.H., Pagani, C., Oliveira, F.L. and Martins, M.P. | Produtividade em formações vegetais amazônicas [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 121-136 |
incollection | |
BibTeX:
@incollection{emilio_produtividade_2014, author = {Ferraz, João B.S. and Luizão, Flávio J. and Zanchi, Fabrício B. and Costa, Heron S. and Quesada, Carlos A. and Gonçalves, José F.C. and Ferreira, Marciel J. and Rodrigues, João V.F.C. and Coral, Sandra C.T. and Florentino, Ana P. P. and Pereira, Anne R. and Paiva, Romilda and Martins, Demétrius L. and Mendonza, Erick M.O. and Lugli, Laynara F. and Campos, Milton C.C. and Santos, Sinara dos and Pereira, Fillipe Eduardo Lemos and Barbosa, Laryssa de A. and Ferreira, Domkarlykisom M. M. and Jordão, Walleson H.C. and Pagani, Caio and Oliveira, Fernanda L. and Martins, Maria P.}, title = {Produtividade em formações vegetais amazônicas}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {121--136}, note = {Section: 11} } |
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Fernandes, S.A.P., Bettiol, W., Cerri, C.C. and Camargo, P. | Sewage sludge effects on gas fluxes at the soil-atmosphere interface, on soil delta C-13 and on total soil carbon and nitrogen | 2005 | Geoderma Vol. 125(1-2), pp. 49-57 |
article | DOI URL |
Abstract: The objective of this work was to study the effect of long-term and continued application of sewage sludge on total carbon and nitrogen, soil delta(13)C and on the gas fluxes at the soil-atmosphere interface under field conditions in the tropical region. To that effect, four applications of sewage sludge from an industrialized region were performed on a Dark Red Dystroferric Latosol. Sludge was incorporated to the soil at concentrations of 0, 1, 2, 4 and 8 times the recommended rate based on their nitrogen content in four consecutive corn cultivations. All sludge rates increased the concentration of soil C and N as compared to the control. The soil C contents at the highest sewage sludge rate increased by 55% and 48% at the layers from 0 to 10 cm and from 10 to 20 cm, respectively, as compared to the control. In the case of soil N, the increase was in the order of 59% and 66% at the highest sludge rate at the layers from 0 to 10 cm and from 10 to 20 cm, respectively, realtive to the control. The increase in soil C content was derived from the sewage sludge, as demonstrated by delta(13)C analyses and, since the soil's delta(13)C contents were negative, it is suggested that the soil is sequestering carbon contained in the se-wage sludge. The application of sewage sludge increased the flux of CO2, N2O and CH4 to the atmosphere, by 220%, 320% and 165% respectively. for the highest sewage sludge rate, when compared to the control. Even though greater emission of gases was observed as compared to the control and to the treatment corresponding to the crop's recommended mineral fertilization, it is important to note that part of the C added via sewage sludge is becoming sequestered in the soil. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{fernandes_sewage_2005, author = {Fernandes, S. A. P. and Bettiol, W. and Cerri, C. C. and Camargo, P.}, title = {Sewage sludge effects on gas fluxes at the soil-atmosphere interface, on soil delta C-13 and on total soil carbon and nitrogen}, journal = {Geoderma}, year = {2005}, volume = {125}, number = {1-2}, pages = {49--57}, url = {://WOS:000226447200005}, doi = {https://doi.org/10.1016/j.geoderma.2004.06.008} } |
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Fernandes, S.A.P., Bettiol, W. and Cerri, C.C. | Effect of sewage sludge on microbial biomass, basal respiration, metabolic quotient and soil enzymatic activity | 2005 | Applied Soil Ecology Vol. 30(1), pp. 65-77 |
article | DOI URL |
Abstract: Monitoring soil quality by means of biological indices can be of help for the management and sustainability of soils that received sewage sludge application. The objective of this study was to evaluate the effect of long-term and continued application of sewage sludge rates on microbial biomass, basal respiration, metabolic quotient and enzymatic activity of a Dark Red Dystroferric Latosol under field conditions in the tropical region. To that effect, four applications of sewage sludge from an industrialized region were performed on a Dark Red Dystroferric Latosol. Sludge was incorporated to the soil at concentrations of 0, 1, 2, 4 and 8 times the recommended rate based on their nitrogen content in four consecutive corn cultivations. The results showed that basal respiration, the C and N microbial biomass, metabolic quotient (qCO(2)) and enzymatic activity in the soil increased as sewage sludge was added, and their values were positively correlated with sewage sludge doses. The activities of soil urease and amylase increased as sludge doses increased and were significantly correlated with soil microbial biomass. These results suggest that the amount of sewage sludge applied has to be calculated based on the N crop needs, and annual applications must be avoided to prevent over-applications. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{fernandes_effect_2005, author = {Fernandes, S. A. P. and Bettiol, W. and Cerri, C. C.}, title = {Effect of sewage sludge on microbial biomass, basal respiration, metabolic quotient and soil enzymatic activity}, journal = {Applied Soil Ecology}, year = {2005}, volume = {30}, number = {1}, pages = {65--77}, url = {://WOS:000231719100007}, doi = {https://doi.org/10.1016/j.apsoil.2004.03.008} } |
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Fernandes, S.A.P., Bernoux, M., Cerri, C.C., Feigl, B.J. and Piccolo, M.C. | Seasonal variation of soil chemical properties and CO2 and CH4 fluxes in unfertilized and P-fertilized pastures in an Ultisol of the Brazilian Amazon | 2002 | Geoderma Vol. 107(3-4), pp. 227-241 |
article | DOI URL |
Abstract: Conversion of the tropical forest to pasture results in changes in the quality and quantity of the soil organic matter (SOM) and other physical and chemical soil properties. Most studies concerning the carbon (C) cycle have focused on soil C stocks. However, little information is available on tropical soil respiration rates. The objectives of this paper are, firstly, to determine how conversion of a natural forest to a pasture and P fertilization affect (1) some soil properties and carbon and nutrient content, and (2) CO2 and CH4 exchanges at the soil-atmosphere interface. For such purposes, a forest-to-pasture chronosequence (pasture established in 1983, 1987, and 1994) was selected at the Fazenda Nova Vida in Rondonia. Soil sampling was done during the dry season (July 1996) and 6 months later during the rainy season (January 1997). Results show increased pH levels, exchangeable cations, and carbon stocks with the pasture installation. On the contrary, the level of available phosphorus decreased with the increasing age of the pastures, justifying the phosphorus fertilization practice. Regarding the CO2 and CH4 fluxes, we found that the forest and pasture soils had greater respiration (CO2 release) rates during the wet season than during the dry season but no specific and significant relationships between the emission and the pasture age was found. Forest soil CH4 consumption rates were three times lower during the wet season, whereas pasture soils showed a net emission of CH4 even during the dry season. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{fernandes_seasonal_2002, author = {Fernandes, S. A. P. and Bernoux, M. and Cerri, C. C. and Feigl, B. J. and Piccolo, M. C.}, title = {Seasonal variation of soil chemical properties and CO2 and CH4 fluxes in unfertilized and P-fertilized pastures in an Ultisol of the Brazilian Amazon}, journal = {Geoderma}, year = {2002}, volume = {107}, number = {3-4}, pages = {227--241}, url = {://WOS:000175898900005}, doi = {https://doi.org/10.1016/s0016-7061(01)00150-1} } |
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Feldpausch, T.R., Rondon, M.A., Fernandes, E.C.M., Riha, S.J. and Wandelli, E. | Carbon and nutrient accumulation in secondary forests regenerating on pastures in central Amazonia | 2004 | Ecological Applications Vol. 14(4), pp. S164-S176 |
article | URL |
Abstract: Over the past three decades, large expanses of forest in the Amazon Basin were converted to pasture, many of which later degraded to woody fallows and were abandoned. While the majority of tropical secondary forest (SF) Studies have examined post-deforestation or post-agricultural succession, we examined post-pasture forest recovery in 10 forests ranging in age from 0 to 14 years since abandonment. We measured aboveground biomass and soil nutrients to 45 cm depth and computed total site carbon (C) and nutrient stocks to gain an understanding of the dynamics of nutrient and C buildup in regenerating SF in central Amazonia. Aboveground biomass accrual was rapid, 11.0 Mg(.)ha(-1.)yr(-1), in the young SFs. Within 12-14 yr, they accumulated up to 128.1 Mg/ha of dry aboveground biomass, equivalent to 25-50% of primary forest biomass in the region. Wood nitrogen (N) and phosphorus (P) concentrations decreased with forest age. Aboveground P and calcium (Ca) stocks accumulated at a rate of 1.2 and 29.4 kg(.)ha(-1.)yr(-1); extractable soil P stocks declined as forest age increased. Although soil stocks of exchangeable Ca (207.0 +/- 23.7 kg/ha) and-extractable P (8.3 +/- 1.5 kg/ha) were low in the first 45 cm, both were rapidly translocated from soil to plant pools. Soil N stocks increased with forest age, probably due to N fixation, atmospheric deposition, and/or subsoil mining. Total soil C storage to 45 cm depth ranged between 42 and 84 Mg/ha, with the first 15 cm storing 40-45% of the total. Total C accrual (7.04 Mg C(.)ha(-1.)yr(-1)) in both aboveground and soil pools was similar or higher than values reported in other studies. Tropical SFs,regrowing on lightly to moderately used pasture rapidly sequester C and rebuild total nutrient capital following pasture abandonment. Translocation of some nutrients from deep soil (textgreater45 cm depth) may be important to sustaining productivity and continuing biomass accumulation in these forests. The soil pool represents the greatest potential for long-term C gains; however, soil nutrient deficits may limit future productivity. | |||||
BibTeX:
@article{feldpausch_carbon_2004, author = {Feldpausch, T. R. and Rondon, M. A. and Fernandes, E. C. M. and Riha, S. J. and Wandelli, E.}, title = {Carbon and nutrient accumulation in secondary forests regenerating on pastures in central Amazonia}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S164--S176}, url = {://WOS:000223269000015} } |
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Feldpausch, T., Riha, S.J., Fernandes, E.M. and Wandelli, E. | Development of forest structure and leaf area in secondary forests regenerating on abandoned pastures in Central Amazonia | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: The area of secondary forest (SF) regenerating from pastures is increasing in the Amazon basin; however, the return of forest and canopy structure following abandonment is not well understood. This study examined the development of leaf area index (LAI), canopy cover, aboveground biomass, stem density, diameter at breast height (DBH), and basal area ( BA) by growth form and diameter class for 10 SFs regenerating from abandoned pastures. Biomass accrual was tree dominated, constituting textgreater= 94% of the total measured biomass in all forests abandoned textgreater= 4 to 6 yr. Vine biomass increased with forest age, but its relative contribution to total biomass decreased with time. The forests were dominated by the tree Vismia spp. (textgreater 50%). Tree stem density peaked after 6 to 8 yr ( 10 320 stems per hectare) before declining by 42% in the 12- to 14-yr-old SFs. Small-diameter tree stems in the 1-5-cm size class composed textgreater 58% of the total stems for all forests. After 12 to 14 yr, there was no significant leaf area below 150-cm height. Leaf area return (LAI = 3.2 after 12 to 14 yr) relative to biomass was slower than literature-reported recovery following slash-and-burn, where LAI can reach primary forest levels ( LAI = 4 - 6) in 5 yr. After 12 to 14 yr, the colonizing vegetation returned some components of forest structure to values reported for primary forest. Basal area and LAI were 50% - 60%, canopy cover and stem density were nearly 100%, and the rapid tree-dominated biomass accrual was 25% - 50% of values reported for primary forest. Biomass accumulation may reach an asymptote earlier than expected because of even-aged, monospecific, untiered stand structure. The very slow leaf area accumulation relative to biomass and to reported values for recovery following slash-and-burn indicates a different canopy development pathway that warrants further investigation of causes ( e. g., nutrient limitations, competition) and effects on processes such as evapotranspiration and soil water uptake, which would influence long-term recovery rates and have regional implications. | |||||
BibTeX:
@article{feldpausch_development_2005, author = {Feldpausch, T.R. and Riha, S. J. and Fernandes, E.C. M. and Wandelli, E.V.}, title = {Development of forest structure and leaf area in secondary forests regenerating on abandoned pastures in Central Amazonia}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241212500001} } |
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Feldpausch, T.R., Prates-Clark, C.D.C., Fernandes, E.C.M. and Riha, S.J. | Secondary forest growth deviation from chronosequence predictions in central Amazonia | 2007 | Global Change Biology Vol. 13(5), pp. 967-979 |
article | DOI URL |
Abstract: Nearly all published rates of secondary forest (SF) regrowth for Amazonia are inferred from chronosequences. We examined SF regrowth on abandoned pastures over a 4-year period to determine if measured rates of forest recovery differ from chronosequence predictions. We studied the emergence, development and death of over 1300 stems in 10 SFs representing three age classes (textless 1-5, 6-10 and 11-14 years old). Mean tree biomass accumulation in both the textless 1-5 and 6-10 years old (4.4 and 5.7 Mg ha(-1) yr(-1), respectively) abandoned pastures was lower than predicted and deviated significantly (57% and 41%) from rates estimated from the chronosequence. The older SFs, with a mean growth rate of 9.9 Mg ha(-1) yr(-1) followed the rate predicted by the chronosequence. Understocking was the primary cause of low biomass recovery rates in the youngest forests; although the youngest stands had a diameter at breast height increment three times the oldest stands, the youngest stands lacked sufficient density to cumulatively produce high biomass accumulation rates. Four years of measurement indicated that the youngest stands had developed 59% of the stems measured in the older stands during the same time period. The 6-10-year-old stands were rapidly self-thinning and approached stem density values measured in the same aged stands at the onset of the study. Mortality was high for all stands, with 54% of the original stems remaining after 4 years in intermediate-aged stands. The forests were dominated by the tree Vismia, which represented 55-66% of the biomass in all stands. The Vismia share of the biomass was decreasing over time, with other genera replacing the pioneer. Our measured rates of regrowth indicate that generalized estimates of forest regrowth through chronosequence studies will overestimate forest regrowth for the youngest forests that were under land use for longer time-periods before abandonment. Certified Emission Reductions under the Clean Development Mechanism of the Kyoto protocol should consider these results when predicting and compensating for carbon sequestered under natural forest management. | |||||
BibTeX:
@article{feldpausch_secondary_2007, author = {Feldpausch, Ted R. and Prates-Clark, Cassia Da Conceicao and Fernandes, Erick C. M. and Riha, Susan J.}, title = {Secondary forest growth deviation from chronosequence predictions in central Amazonia}, journal = {Global Change Biology}, year = {2007}, volume = {13}, number = {5}, pages = {967--979}, url = {://WOS:000245987300005}, doi = {https://doi.org/10.1111/j.1365-2486.2007.01344.x} } |
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Feldpausch, T.R., Phillips, O.L., Brienen, R.J.W., Gloor, E., Lloyd, J., Lopez-Gonzalez, G., Monteagudo-Mendoza, A., Y. Malhi, A. Alarcón, E. Álvarez Dávila, P. Alvarez-Loayza, A. Andrade, L. E. O. C. Aragao, L. Arroyo, G. A. Aymard C., T. R. Baker, C. Baraloto, J. Barroso, D. Bonal, W. Castro, V. Chama, J. Chave, T. F. Domingues, S. Fauset, N. Groot, E. Honorio Coronado, S. Laurance, W. F. Laurance, S. L. Lewis, J. C. Licona, B. S. Marimon, B. H. Marimon-Junior, C. Mendoza Bautista, D. A. Neill, E.A.O., C. Oliveira dos Santos, N. C. Pallqui Camacho, G. Pardo-Molina, A. Prieto, C. A. Quesada, F. Ramírez, H. Ramírez-Angulo, M. Réjou-Méchain, A. Rudas, G. Saiz, R. P. Salomão, J. E. Silva-Espejo, M. Silveira, H. ter Steege, J. Stropp, J. Terborgh, R. Thomas-Caesar, G. M. F. van der Heijden, R. Vásquez Martinez, E. Vilanova and Vos, V.A. | Amazon forest response to repeated droughts [BibTeX] |
2016 | Global Biogeochemical Cycles Vol. 30, pp. 964-982 |
article | DOI |
BibTeX:
@article{feldpausch_amazon_2016, author = {Feldpausch, T. R. and Phillips, O. L. and Brienen, R. J. W. and Gloor, E. and Lloyd, J. and Lopez-Gonzalez, G. and Monteagudo-Mendoza, A. and Y. Malhi and A. Alarcón and E. Álvarez Dávila and P. Alvarez-Loayza and A. Andrade and L. E. O. C. Aragao and L. Arroyo and G. A. Aymard C. and T. R. Baker and C. Baraloto and J. Barroso and D. Bonal and W. Castro and V. Chama and J. Chave and T. F. Domingues and S. Fauset and N. Groot and E. Honorio Coronado and S. Laurance and W. F. Laurance and S. L. Lewis and J. C. Licona and B. S. Marimon and B. H. Marimon-Junior and C. Mendoza Bautista and D. A. Neill, E. A. Oliveira and C. Oliveira dos Santos and N. C. Pallqui Camacho and G. Pardo-Molina and A. Prieto and C. A. Quesada and F. Ramírez and H. Ramírez-Angulo and M. Réjou-Méchain and A. Rudas and G. Saiz and R. P. Salomão and J. E. Silva-Espejo and M. Silveira and H. ter Steege and J. Stropp and J. Terborgh and R. Thomas-Caesar and G. M. F. van der Heijden and R. Vásquez Martinez and E. Vilanova and Vos, V. A.}, title = {Amazon forest response to repeated droughts}, journal = {Global Biogeochemical Cycles}, year = {2016}, volume = {30}, pages = {964--982}, doi = {https://doi.org/10.1002/2015GB005133} } |
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Feldpausch, T.R., McDonald, A.J., Passos, C.A.M., Lehmann, J. and Riha, S.J. | Biomass, harvestable area, and forest structure estimated from commercial timber inventories and remotely sensed imagery in southern Amazonia | 2006 | Forest Ecology and Management Vol. 233(1), pp. 121-132 |
article | DOI URL |
Abstract: The purpose of this study was to determine if spatially-explicit commercial timber inventories (CTI) could be used in conjunction with satellite imagery to improve timber assessments and forest biomass estimates in Amazonia. As part of a CTI, all commercial trees textgreater= 45 cm DBH were measured and georeferenced in 3500 ha of a logging concession in NW Mato Grosso, Brazil. A scientific inventory was conducted of all trees and palms textgreater= 10 cm DBH in 11.1 ha of this area. A total of textgreater 20,000 trees were sampled for both inventories. To characterize vegetation radiance and topographic features, regional LANDSAT TM and ASTER images were obtained. Using a stream network derived from the ASTER-based 30 m digital elevation model (DEM), a procedure was developed to predict areas excluded from logging based on reduced impact logging (RIL) criteria. A topographic index (TI) computed from the DEM was used to identify areas with similar hydrologic regimes and to distinguish upland and lowland areas. Some timber species were associated with convergent landscape positions (i.e., higher TI values). There were significant differences in timber density and aboveground biomass (AGB) in upland (6.0 stems ha(-1), 33 Mg ha(-1)) versus lowland (5.4 stems ha(-1), 29 Mg ha(-1)) areas. Upland and lowland, and timber and non-timber areas could be distinguished through single and principal component analysis of LANDSAT bands. However, radiance differences between areas with and without commercial timber on a sub-hectare scale were small, indicating LANDSAT images would have limited utility for assessing commercial timber distribution at this scale. Assuming a 50 m stream buffer, areas protected from logging ranged from 7% (third order streams and above) to 28% (first order and above) of the total area. There was a strong positive relationship between AGB based on the scientific inventory of all trees and from the commercial timber, indicating that the CTI could be used in conjunction with limited additional sampling to predict total AGB (276 Mg ha(-1)). The methods developed in this study could be useful for facilitating commercial inventory practices, understanding the relationship of tree species distribution to landscape features, and improving the novel use of CTIs to estimate AGB. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{feldpausch_biomass_2006, author = {Feldpausch, Ted R. and McDonald, Andrew J. and Passos, Carlos A. M. and Lehmann, Johannes and Riha, Susan J.}, title = {Biomass, harvestable area, and forest structure estimated from commercial timber inventories and remotely sensed imagery in southern Amazonia}, journal = {Forest Ecology and Management}, year = {2006}, volume = {233}, number = {1}, pages = {121--132}, url = {://WOS:000240409800014}, doi = {https://doi.org/10.1016/j.foreco.2006.06.016} } |
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Feldpausch, T.R., Lloyd, J., Lewis, S.L., Brienen, R.J.W., Gloor, M., Monteagudo Mendoza, A., Lopez-Gonzalez, G., Banin, L., Abu Salim, K., Affum-Baffoe, K., Alexiades, M., Almeida, S., Amaral, I., Andrade, A., Aragão, L.E.O.C., Araujo Murakami, A., Arets, E.J.M.M., Arroyo G. A., L.A.C., Baker, T.R., Bánki, O.S., Berry, N.J., Cardozo, N., Chave, J., Comiskey, J.A. and al. , e. | Tree height integrated into pantropical forest biomass estimates [BibTeX] |
2012 | Biogeosciences Vol. 9, pp. 3381-3403 |
article | |
BibTeX:
@article{feldpausch_tree_2012, author = {Feldpausch, T. R. and Lloyd, J. and Lewis, S. L. and Brienen, R. J. W. and Gloor, M. and Monteagudo Mendoza, A. and Lopez-Gonzalez, G. and Banin, L. and Abu Salim, K. and Affum-Baffoe, K. and Alexiades, M. and Almeida, S. and Amaral, I. and Andrade, A. and Aragão, L. E. O. C. and Araujo Murakami, A. and Arets, E. J. M. M. and Arroyo, G. A., L. Aymard C. and Baker, T. R. and Bánki, O. S. and Berry, N. J. and Cardozo, N. and Chave, J. and Comiskey, J. A. and al., et}, title = {Tree height integrated into pantropical forest biomass estimates}, journal = {Biogeosciences}, year = {2012}, volume = {9}, pages = {3381--3403} } |
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Feldpausch, T.R., Jirka, S., Passos, C.A.M., Jasper, F. and Riha, S.J. | When big trees fall: Damage and carbon export by reduced impact logging in southern Amazonia | 2005 | Forest Ecology and Management Vol. 219(2-3), pp. 199-215 |
article | DOI URL |
Abstract: We examined carbon export in whole logs and carbon accumulation as coarse woody debris (CWD) produced from forest damage during all phases of the first and second year of a certified reduced impact logging (RIL) timber harvest in southern Amazonia. Our measurements included a 100% survey of roads and log decks, assessment of canopy damage and ground disturbance in skid trails and tree-fall gaps, and measurement of carbon exported from the site in logs. Log deck and road construction crushed one and five trees in the 10-60 cm diameter at breast height (DBH) class per hectare logged, disturbed areas of 24 and 100 m(2) ha(-1), respectively, and together disturbed about 1% of the forest. On average 1.1-2.6 trees ha I were harvested over the two years. Logged gaps constituted the greatest disturbance on an area basis (4-10% of the forest) and CWD generation (1.9-4.4 Mg ha(-1) logged). In gaps, felled trees severed or crushed 10 trees textgreater= 10 cm DBH per tree logged, which corresponded to 1.7 Mg ha of CWD per tree logged. Crown height - measured from the first bifurcation to the top of the crown - rather than tree height was the better predictor of gap size formed from tree felling (R-2 = 0.41). Logging activities significantly reduced leaf area in roads, log decks and gaps, with the greatest reduction (48%) in log decks and least in logged gaps and roads (28-33%) compared to undisturbed forest. A total of 37 species were harvested, with 36% of the total trees harvested and 48% of the total carbon exported from the site in three of the most common species. Logging damage produced 4.9-8.8 Mg C ha 1 logged of CWD from all phases of the operation. Carbon export in whole logs (2.1-3.7 Mg C ha(-1) logged) represented 1-3% of the total standing forest carbon textgreater= 10 cm DBH (138 Mg C hat). The mean carbon ratio (per hectare logged) of C in CWD to C exported in logs was 2.4. The disturbance, damage, carbon export and CWD data we present advances understanding of the effect of selective logging on tropical forest dynamics of the Amazon Basin. Our results indicate that certified timber harvest in Amazonia under RIL is a viable forest management option to reduce damage and CWD production compared to conventional logging (CL) practices; however, the benefits of disturbance reduction from RIL relative to CL are only realized at greater volumes of timber extraction. (c) 2005 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{feldpausch_when_2005, author = {Feldpausch, T. R. and Jirka, S. and Passos, C. A. M. and Jasper, F. and Riha, S. J.}, title = {When big trees fall: Damage and carbon export by reduced impact logging in southern Amazonia}, journal = {Forest Ecology and Management}, year = {2005}, volume = {219}, number = {2-3}, pages = {199--215}, url = {://WOS:000234166100007}, doi = {https://doi.org/10.1016/j.foreco.2005.09.003} } |
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Feldpausch, T.R., Coutoz, E.G., Rodrigues, L.C., Pauletto, D., Johnson, M.S., Faheyk, T.J., Lehmann, J. and Riha, S.J. | Nitrogen aboveground turnover and soil stocks to 8 m depth in primary and selectively logged forest in southern Amazonia | 2010 | Global Change Biology Vol. 16(6), pp. 1793-1805 |
article | DOI URL |
Abstract: Extensive areas of Amazonia undergo selective logging, modifying forest structure and nutrient cycles. Anthropogenic-accelerated rates of nitrogen (N) turnover could increase N loss and affect regeneration, carbon sequestration and timber production. We quantified leaf area reduction, canopy opening and downed biomass and resultant N flux from reduced impact logging (RIL) activities. We compared canopy reduction, surface soil moisture and nitrate to 8 m depth between logged gaps and intact primary forest to determine if logging activities increase subsoil nitrate. To test long-term logging effects, we evaluated surface N stocks along a 12-year postlogging chronosequence. At the harvest rate of 2.6 trees ha-1, total N additions in logging gaps, including leaves and wood from felled crowns (24.8 kg N ha-1) and other killed trees (41.9 kg N ha-1), accounted for over 80% of the total N addition to aboveground necromass from all logging activities (81.9 kg N ha-1). Despite this N turnover by logging, belowground nitrate storage to 8 m depth did not differ between logging gaps and primary forest at the low harvest rate and disturbance intensity of this study. Soil water depletion also did not differ between gaps and primary forest over 1 year, indicating the impact on belowground inorganic N was low. Compared with primary forest, nitrate concentrations to 8 m depth in logging gaps were only significantly higher at 60-100 cm, suggesting some N redistribution beyond the bulk of the fine roots in logging gaps. Extrapolated to the Amazon Basin scale, we provide a conservative estimate that logging damage and bole export under RIL would turn over 0.14 +/- 0.07 to 0.23 +/- 0.12 Tg N yr-1 based on 1999-2002 selective logging rates. Greater damage during conventional selective logging would cause higher N turnover throughout the Amazon Basin than our results based on RIL. | |||||
BibTeX:
@article{feldpausch_nitrogen_2010, author = {Feldpausch, Ted R. and Coutoz, Eduardo G. and Rodrigues, Luiz Carlos and Pauletto, Daniela and Johnson, Mark S. and Faheyk, Timothy J. and Lehmann, Johannes and Riha, Susan J.}, title = {Nitrogen aboveground turnover and soil stocks to 8 m depth in primary and selectively logged forest in southern Amazonia}, journal = {Global Change Biology}, year = {2010}, volume = {16}, number = {6}, pages = {1793--1805}, url = {://WOS:000277288900012}, doi = {https://doi.org/10.1111/j.1365-2486.2009.02068.x} } |
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Feldpausch, T.R., Banin, L., Phillips, O.L., Baker, T.R., Lewis, S.L., Quesada, C.A., Affum-Baffoe, K., Arets, E.J.M.M., Berry, N.J., Bird, M., Brondizio, E.S., de Camargo, P., Chave, J., Djagbletey, G., Domingues, T.F., Drescher, M., Fearnside, P.M., Franca, M.B., Fyllas, N.M., Lopez-Gonzalez, G., Hladik, A., Higuchi, N., Hunter, M.O., Iida, Y., Salim, K.A., Kassim, A.R., Keller, M., Kemp, J., King, D.A., Lovett, J.C., Marimon, B.S., Marimon-Junior, B.H., Lenza, E., Marshall, A.R., Metcalfe, D.J., Mitchard, E.T.A., Moran, E.F., Nelson, B.W., Nilus, R., Nogueira, E.M., Palace, M., Patino, S., Peh, K.S.H., Raventos, M.T., Reitsma, J.M., Saiz, G., Schrodt, F., Sonke, B., Taedoumg, H.E., Tan, S., White, L., Woell, H. and Lloyd, J. | Height-diameter allometry of tropical forest trees | 2011 | Biogeosciences Vol. 8(5), pp. 1081-1106 |
article | DOI URL |
Abstract: Tropical tree height-diameter (H:D) relationships may vary by forest type and region making large-scale estimates of above-ground biomass subject to bias if they ignore these differences in stem allometry. We have therefore developed a new global tropical forest database consisting of 39 955 concurrent H and D measurements encompassing 283 sites in 22 tropical countries. Utilising this database, our objectives were: 1. to determine if H:D relationships differ by geographic region and forest type (wet to dry forests, including zones of tension where forest and savanna overlap). 2. to ascertain if the H:D relationship is modulated by climate and/or forest structural characteristics (e.g. stand-level basal area, A). 3. to develop H:D allometric equations and evaluate biases to reduce error in future local-to-global estimates of tropical forest biomass. Annual precipitation coefficient of variation (P(V)), dry season length (S(D)), and mean annual air temperature (T(A)) emerged as key drivers of variation in H:D relationships at the pantropical and region scales. Vegetation structure also played a role with trees in forests of a high A being, on average, taller at any given D. After the effects of environment and forest structure are taken into account, two main regional groups can be identified. Forests in Asia, Africa and the Guyana Shield all have, on average, similar H:D relationships, but with trees in the forests of much of the Amazon Basin and tropical Australia typically being shorter at any given D than their counterparts elsewhere. The region-environment-structure model with the lowest Akaike's information criterion and lowest deviation estimated stand-level H across all plots to within a median -2.7 to 0.9% of the true value. Some of the plot-to-plot variability in H:D relationships not accounted for by this model could be attributed to variations in soil physical conditions. Other things being equal, trees tend to be more slender in the absence of soil physical constraints, especially at smaller D. Pantropical and continental-level models provided less robust estimates of H, especially when the roles of climate and stand structure in modulating H:D allometry were not simultaneously taken into account. | |||||
BibTeX:
@article{feldpausch_height-diameter_2011, author = {Feldpausch, T. R. and Banin, L. and Phillips, O. L. and Baker, T. R. and Lewis, S. L. and Quesada, C. A. and Affum-Baffoe, K. and Arets, E. J. M. M. and Berry, N. J. and Bird, M. and Brondizio, E. S. and de Camargo, P. and Chave, J. and Djagbletey, G. and Domingues, T. F. and Drescher, M. and Fearnside, P. M. and Franca, M. B. and Fyllas, N. M. and Lopez-Gonzalez, G. and Hladik, A. and Higuchi, N. and Hunter, M. O. and Iida, Y. and Salim, K. A. and Kassim, A. R. and Keller, M. and Kemp, J. and King, D. A. and Lovett, J. C. and Marimon, B. S. and Marimon-Junior, B. H. and Lenza, E. and Marshall, A. R. and Metcalfe, D. J. and Mitchard, E. T. A. and Moran, E. F. and Nelson, B. W. and Nilus, R. and Nogueira, E. M. and Palace, M. and Patino, S. and Peh, K. S. H. and Raventos, M. T. and Reitsma, J. M. and Saiz, G. and Schrodt, F. and Sonke, B. and Taedoumg, H. E. and Tan, S. and White, L. and Woell, H. and Lloyd, J.}, title = {Height-diameter allometry of tropical forest trees}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {5}, pages = {1081--1106}, url = {://WOS:000291003200004}, doi = {https://doi.org/10.5194/bg-8-1081-2011} } |
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Feigl, B., Cerri, C., Piccolo, M., Noronha, N., Augusti, K., Melillo, J., Eschenbrenner, V. and Melo, L. | Biological survey of a low-productivity pasture in Rondonia state, Brazil | 2006 | Outlook on Agriculture Vol. 35(3), pp. 199-208 |
article | URL |
Abstract: Some years after their establishment, areas of pasture planted to Brachiaria and other African grasses in the Brazilian Amazon region show a continuous decline in forage and animal productivity. If no remedial measures are taken, plant cover decreases, the areas become invaded by weeds and the soil becomes compacted. However, this process is not yet well understood. A series of evaluations was implemented in a 20-year-old pasture located on a representative cattle ranch in Rondonia state to estimate the botanical composition, standing phytomass (including leaf litter), macrofauna species richness and microbial biomass to characterize the soil biological conditions of a pasture site about to degrade and before rehabilitation practices were adopted. The aim was to characterize the type and degree of degradation already completed to record the baseline against which the results obtained by restoration practices could be compared. Soil C, N and available P stocks were 20.4 Mg C ha(-1), 1.5 Mg N ha(-1) and 8.3 kg P ha(-1) respectively, higher than under natural forest and close to those found in productive pasture sites. Physical and chemical analyses did not indicate effective degradation. Woody species dominated by trees and shrubs such as Tabebuia spp., Erisma uncinatum and Vismia guianensis occupied 15-18% of the total area. Babacu palm (Orbignya phalerata Mart) covered 12%, herbaceous weeds 4-11%, while the rest (mean 63.5%) contained a mixture of Brachiaria brizantha and Pannicum maximum. The high biomass accrual and the diversity of species suggest that the soil is still able to support a productive forage grass cover. Biomass above ground, including litter layer, totalled 131 Mg DM ha(-1), or 42% of original forest. High standing biomass in the experimental area can be attributed to insufficient and/or inapropriate weed control since the early stage of pasture installation. Reformation of the study site would implicate a potential above-ground input of about 130 Mg C ha(-1) (C/N = 49; C/P = 744), besides another 6.4 Mg C ha(-1) derived from root biomass decomposition. The most frequently found invertebrates were the termites (368 ind m(-2)), restricted to the 0-10 cm layer, while earthworms (204 ind m(-2)), ants (152 ind m(-2)) and Coleoptera (146 ind m(-2)) were found to a depth of 30 cm. The presence of so-called ecosystem engineers indicates that this population, probably comprising anecics and rhizophagous species, is related to the high root and litter density. The average number of representatives is more comparable with sites undergoing regrowth of secondary vegetation than with degraded pastures. Microbiological evidence indicates that the pasture studied constitutes an unstressed system about to accumulate organic matter in the soil. | |||||
BibTeX:
@article{feigl_biological_2006, author = {Feigl, Brigitte and Cerri, Carlos and Piccolo, Marisa and Noronha, Norberto and Augusti, Karine and Melillo, Jerry and Eschenbrenner, Vincent and Melo, Lineu}, title = {Biological survey of a low-productivity pasture in Rondonia state, Brazil}, journal = {Outlook on Agriculture}, year = {2006}, volume = {35}, number = {3}, pages = {199--208}, url = {://WOS:000241282400006} } |
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Fearnside, P.M., Laurance, W.F., Albernaz, A.K.M., Vasconcelos, H.L. and Ferreira, L.V. | A delicate balance in Amazonia - Response [BibTeX] |
2005 | Science Vol. 307(5712), pp. 1045-1045 |
article | URL |
BibTeX:
@article{fearnside_delicate_2005, author = {Fearnside, P. M. and Laurance, W. F. and Albernaz, A. K. M. and Vasconcelos, H. L. and Ferreira, L. V.}, title = {A delicate balance in Amazonia - Response}, journal = {Science}, year = {2005}, volume = {307}, number = {5712}, pages = {1045--1045}, url = {://WOS:000227197300023} } |
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Fearnside, P.M. and Laurance, W.F. | Tropical deforestation and greenhouse-gas emissions | 2004 | Ecological Applications Vol. 14(4), pp. 982-986 |
article | DOI URL |
Abstract: A recent (2002) analysis concluded that rates of tropical deforestation and atmospheric carbon emissions during the 1990-1997 interval were lower than previously suggested. We challenged this assertion with respect to tropical carbon emissions, but our conclusions were disputed by the authors of the original study. Here we provide further evidence to support our conclusion that the effect of tropical deforestation on greenhouse-gas emissions and global warming is substantial. At least for Brazilian Amazonia, the net impact of tropical deforestation on global warming may be more than double that estimated in the recent study. | |||||
BibTeX:
@article{fearnside_tropical_2004, author = {Fearnside, P. M. and Laurance, W. F.}, title = {Tropical deforestation and greenhouse-gas emissions}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {982--986}, url = {://WOS:000223156600003}, doi = {https://doi.org/10.1890/03-5225} } |
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Fearnside, P.M. and Laurance, W.F. | Comment on "Determination of deforestation rates of the world's humid tropical forests" [BibTeX] |
2003 | Science Vol. 299(5609) |
article | URL |
BibTeX:
@article{fearnside_comment_2003, author = {Fearnside, P. M. and Laurance, W. F.}, title = {Comment on "Determination of deforestation rates of the world's humid tropical forests"}, journal = {Science}, year = {2003}, volume = {299}, number = {5609}, url = {://WOS:000180960000024} } |
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Fearnside, P.M., Graça, P.M.L.d.A. and Rodrigues, F.J.A. | Burning of Amazonian rainforests: burning efficiency and charcoal formation in forest cleared for cattle pasture near Manaus, Brazil [BibTeX] |
2001 | Forest Ecology and Management Vol. 146(1-3), pp. 115-128 |
article | DOI URL |
BibTeX:
@article{fearnside_burning_2001, author = {Fearnside, Philip M. and Graça, Paulo Maurı́cio Lima de Alencastro and Rodrigues, Fernando José Alves}, title = {Burning of Amazonian rainforests: burning efficiency and charcoal formation in forest cleared for cattle pasture near Manaus, Brazil}, journal = {Forest Ecology and Management}, year = {2001}, volume = {146}, number = {1-3}, pages = {115--128}, url = {://WOS:000168636800010}, doi = {https://doi.org/10.1016/s0378-1127(00)00450-3} } |
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Fearnside, P.M. and Barbosa, R.I. | Soil carbon changes from conversion of forest to pasture in Brazilian Amazonia | 1998 | Forest Ecology and Management Vol. 108(1-2), pp. 147-166 |
article | DOI URL |
Abstract: Soils in Brazilian Amazonia may contain up to 136 Ct of carbon to a depth of 8 m, of which 47 Gt are in the top meter. The current rapid conversion of Amazonian forest to cattle pasture makes disturbance of this carbon stock potentially important to the global carbon balance and net greenhouse gas emissions. Information on the response of soil carbon pools to conversion to cattle pasture is conflicting. Some of the varied results that have been reported can be explained by effects of soil compaction, clay content and seasonal changes. Most studies have compared roughly simultaneous samples taken at nearby sites with different use histories (i.e., 'chronosequences'); a clear need exists for longitudinal studies in which soil carbon stocks and related parameters are monitored over time at fixed locations. Whether pasture soils are a net sink or a net source of carbon depends on their management, but an approximation of the fraction of pastures under 'typical' and 'ideal' management practices indicates that pasture soils in Brazilian Amazonia are a net carbon source, with the upper 8 m releasing an average of 12.0 t C/ha in land maintained as pasture in the equilibrium landscape that is established in the decades following deforestation. Considering the equilibrium landscape as a whole, which is dominated by pasture and secondary forest derived from pasture, the average net release of soil carbon is 8.5 t C/ha, or 11.7 x 10(6) t C for the 1.38 x 10(6) ha cleared in 1990. Only 3% of the calculated emission comes from below 1 m depth, but the ultimate contribution from deep layers may be substantially greater. The land area affected by soil C losses under pasture is not restricted to the portion of the region maintained under pasture in the equilibrium landscape, but also the portion under secondary forests derived from pasture. Pasture effects from deforestation in 1990 represent a net committed emission from soils of 9.2 x 106 t C, or 79% of the total release from soils from deforestation in that year. Soil emissions from Amazonian deforestation represent a quantity of carbon approximately 20% as large as Brazil's annual emission from fossil fuels. (C) 1998 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{fearnside_soil_1998, author = {Fearnside, P. M. and Barbosa, R. I.}, title = {Soil carbon changes from conversion of forest to pasture in Brazilian Amazonia}, journal = {Forest Ecology and Management}, year = {1998}, volume = {108}, number = {1-2}, pages = {147--166}, url = {://WOS:000075010300014}, doi = {https://doi.org/10.1016/s0378-1127(98)00222-9} } |
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Fearnside, P.M. and Barbosa, K.I. | Accelerating deforestation in Brazilian Amazonia: towards answering open questions | 2004 | Environmental Conservation Vol. 31(1), pp. 7-10 |
article | DOI URL |
Abstract: The annual rate of deforestation in Brazilian Amazonia jumped by an estimated 40% between 2001 and 2002. This increase is in addition to a 15% upward revision by the Brazilian government of the estimated rate for 2001. Examination of the data underlying these estimates and comparisons with other measurements indicates that important questions remain unanswered, especially in the state of Mato Grosso, where assessment of the effectiveness of a deforestation licensing and control programme is critical to future efforts to contain forest destruction. The increase in deforestation rate in Mato Grosso in 2002 (23%) was less than half the increase in the remainder of Brazilian Amazonia (55%), indicating that the state government's deforestation control programme may have had some effect. | |||||
BibTeX:
@article{fearnside_accelerating_2004, author = {Fearnside, P. M. and Barbosa, K. I.}, title = {Accelerating deforestation in Brazilian Amazonia: towards answering open questions}, journal = {Environmental Conservation}, year = {2004}, volume = {31}, number = {1}, pages = {7--10}, url = {://WOS:000221643800003 http://journals.cambridge.org/download.php?file=%2F4981_69B95B1BADBB977B7A8B29B1C69525B3_journals__ENC_ENC31_01_S0376892904001055a.pdf&cover=Y&code=293c36dba5b072a8215d621ee092fd38}, doi = {https://doi.org/10.1017/s0376892904001055} } |
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Fearnside, P.M. | The Impact of Land Use on Carbon Stocks and Fluxes in Brazilian Amazonia: Implications for Policy [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 385-405 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_impact_2016, author = {Fearnside, P. M.}, title = {The Impact of Land Use on Carbon Stocks and Fluxes in Brazilian Amazonia: Implications for Policy}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {385--405}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Fearnside, P.M. | The Roles and Movements of Actors in the Deforestation of Brazilian Amazonia | 2008 | Ecology and Society Vol. 13(1) |
article | URL |
Abstract: Containing the advance of deforestation in Brazilian Amazonia requires understanding the roles and movements of the actors involved. The importance of different actors varies widely among locations within the region, and also evolves at any particular site over the course of frontier establishment and consolidation. Landless migrants have significant roles in clearing the land they occupy and in motivating landholders to clear as a defense against invasion or expropriation. Colonists in official settlements and other small farmers also are responsible for substantial amounts of clearing, but ranchers constitute the largest component of the region's clearing. This group is most responsive to macroeconomic changes affecting such factors as commodity prices, and also receives substantial subsidies. Ulterior motives, such as land speculation and money laundering, also affect this group. Drug trafficking and money laundering represent strong forces in some areas and help spread deforestation where it would be unprofitable based only on the legitimate economy. Goldminers increase the population in distant areas and subsequently enter the ranks of other groups. Work as laborers or debt slaves provides an important entry to the region for poor migrants from northeast Brazil, providing cheap labor to large ranches and a large source of entrants to other groups, such as landless farmers and colonists. Capitalized farmers, including agribusiness for soy production, have tremendous impact in certain areas, such as Mato Grosso. This group responds to commodity markets and provides justification for major infrastructure projects. Landgrabbers, or grileiros, are important in entering public land and beginning the process of deforestation and transfer of land to subsequent groups of actors. These include sawmill owners and loggers, who play an important role in generating funds for clearing by other groups, ranging from landless migrants to large ranchers. They also build endogenous roads, facilitating the entry of other actors. Future movements of actors will be influenced by major infrastructure plans, such as those for hydroelectric dams. Policies for reducing deforestation must include removing motives for deforestation by stopping the practice of regularizing land claims and by cutting subsidies. The rule of law must be established throughout the region by completing the cadaster, or register, of land titles and by reinforcing command and control. Movement to the frontier needs to be discouraged by exercising restraint in approving infrastructure such as highways, and by creating and protecting conservation units. Economic alternatives to deforestation should be fostered by generating employment in source areas and in alternative migration destinations, by supporting sustainable uses of forest, by supporting alternative supply of domestic markets for products such as timber, and by rewarding the environmental services of standing forest. | |||||
BibTeX:
@article{fearnside_roles_2008, author = {Fearnside, Philip M.}, title = {The Roles and Movements of Actors in the Deforestation of Brazilian Amazonia}, journal = {Ecology and Society}, year = {2008}, volume = {13}, number = {1}, url = {://WOS:000261176100036} } |
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Fearnside, P.M. | On the value of temporary carbon: a comment on Kirschbaum | 2008 | Mitigation and Adaptation Strategies for Global Change Vol. 13(3), pp. 207-210 |
article | DOI URL |
Abstract: A recent paper by Miko Kirschbaum (Mitigat Adapt Strategies Glob Change 11(5-6): 1151-1164, 2006) argues that temporary carbon (C) storage has "virtually no climate-change mitigation value.'' However, temporary carbon has value in delaying global warming that needs to be recognized in carbon accounting methodologies. The conclusions reached are very sensitive to any value that is attached to time. Basing analysis exclusively on the maximum temperature reached within a 100-year time frame ignores other important impacts of global warming that also need to be included when mitigation strategies are assessed. The relative weightings for long-term versus short-term impacts represent policy choices that result in a greater or a lesser value being attributed to temporary carbon, but that value should not be zero. Global warming is too formidable an enemy to allow us the luxury of discarding part of our arsenal in fighting against it. Both reducing fossil-fuel combustion and increasing biosphere carbon stocks are needed. | |||||
BibTeX:
@article{fearnside_value_2008, author = {Fearnside, Philip M.}, title = {On the value of temporary carbon: a comment on Kirschbaum}, journal = {Mitigation and Adaptation Strategies for Global Change}, year = {2008}, volume = {13}, number = {3}, pages = {207--210}, url = {://WOS:000207663000001}, doi = {https://doi.org/10.1007/s11027-007-9112-7} } |
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Fearnside, P. | Desmatamento na Amazônia: dinâmica, impactos e controle [BibTeX] |
2006 | Acta Amazonica Vol. 36(3), pp. 395 - 400 |
article | |
BibTeX:
@article{fearnside_desmatamento_2006, author = {Fearnside, P.M.}, title = {Desmatamento na Amazônia: dinâmica, impactos e controle}, journal = {Acta Amazonica}, year = {2006}, volume = {36}, number = {3}, pages = {395 -- 400} } |
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Fearnside, P.M. | Deforestation in Brazilian Amazonia: History, rates, and consequences | 2005 | Conservation Biology Vol. 19(3), pp. 680-688 |
article | DOI URL |
Abstract: Brazil's Amazon forest remained largely intact until the "modern" era of deforestation began with the inauguration of the Transamazon Highway in 1970. Amazonian deforestation rates have trended upward since 1991, with clearing proceeding at a variable but rapid pace. Although Amazonian forests are cut for various reasons, cattle ranching predominates. The large and medium-sized ranches account for about 70% of clearing activity. Profit from beef cattle is only one of the income sources that make deforestation profitable. Forest degradation results from logging, ground fires (facilitated by logging), and the effects of fragmentation and edge formation. Degradation contributes to forest loss. The impacts of deforestation include loss of biodiversity, reduced water cycling (and rainfall), and contributions to global warming. Strategies to slow deforestation include repression through licensing procedures, monitoring, and fines. The severity of penalties for deforestation needs to be sufficient to deter illegal clearing but not so great as to be unenforceable. Policy reform is also needed to address root causes of deforestation, including the role of clearing in establishing land claims. | |||||
BibTeX:
@article{fearnside_deforestation_2005, author = {Fearnside, P. M.}, title = {Deforestation in Brazilian Amazonia: History, rates, and consequences}, journal = {Conservation Biology}, year = {2005}, volume = {19}, number = {3}, pages = {680--688}, url = {://WOS:000229448100016}, doi = {https://doi.org/10.1111/j.1523-1739.2005.00697.x} } |
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Fearnside, P.M. | Conservation policy in Brazilian Amazonia: Understanding the dilemmas | 2003 | World Development Vol. 31(5), pp. 757-779 |
article | DOI URL |
Abstract: Conservation policy in Brazilian Amazonia is rapidly evolving. The dynamics of different interest groups affect the political economy of land use. Choices include allocation of effort between completely and partially protected areas and between creation of new conservation units versus consolidation of existing units. Tensions between different levels of government, different groups of nongovernmental organizations, and between the public versus private sectors are evident. While the conflicting interests of such groups present many barriers, they also offer conservation opportunities. Negotiation with indigenous peoples represents one of the most critical areas for the long-term future of natural ecosystems in the region. (C) 2003 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{fearnside_conservation_2003, author = {Fearnside, P. M.}, title = {Conservation policy in Brazilian Amazonia: Understanding the dilemmas}, journal = {World Development}, year = {2003}, volume = {31}, number = {5}, pages = {757--779}, url = {://WOS:000182806300001}, doi = {https://doi.org/10.1016/s0305-750x(03)00011-1} } |
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Fearnside, P.M. | Time preference in global warming calculations: a proposal for a unified index | 2002 | Ecological Economics Vol. 41(1), pp. 21-31 |
article | DOI URL |
Abstract: Many aspects of the calculation of the impacts of greenhouse gas (GHG) emissions and the costs and benefits of possible response options are highly sensitive to the way in which time preference is incorporated into the computations. The Intergovernmental Panel on Climate Change (IPCC) used global warming potentials (GWPs) to standardize inputs of different gases with differing radiative forcings and atmospheric lifetimes; in the results emphasized by the IPCC's Second Assessment Report, a 100-year time horizon and no discounting is used, and this has been adopted by the Kyoto Protocol for use in the first commitment period (2008-2012). Here an alternative unified index is proposed that assigns explicit weights to the interests of different generations. In contrast to discounting (including the zero discount rate used by the IPCC), the generationally weighted index forces policy makers to face the moral assumptions that underlie their choices related to global warming. (C) 2002 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{fearnside_time_2002, author = {Fearnside, P. M.}, title = {Time preference in global warming calculations: a proposal for a unified index}, journal = {Ecological Economics}, year = {2002}, volume = {41}, number = {1}, pages = {21--31}, url = {://WOS:000177018100003}, doi = {https://doi.org/10.1016/s0921-8009(02)00004-6} } |
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Fearnside, P.M. | Avanca Brasil: Environmental and social consequences of Brazil's planned infrastructure in Amazonia | 2002 | Environmental Management Vol. 30(6), pp. 735-747 |
article | DOI URL |
Abstract: "Avanpa Brasil" (Forward Brazil) is a package of 338 projects throughout Brazil; the portion of the plan to be carried out in Brazil's Legal Amazon region totals US$43 billion over 8 years, US$20 billion of which would be for infrastructure causing environmental damage. Brazil's environmental impact assessment system is not yet capable of coping with the challenge presented by Avanpa Brasil. Generic problems with the licensing process include stimulation of a lobby in favor of construction before decisions are made on the advisability of the projects, the "dragging effect" of third parties, whereby economic activity is attracted to the infrastructure but escapes the environmental impact assessment system, a tendency for consulting firms to produce favorable reports, a bureaucratic emphasis on the existence of steps without regard to the content of what is said, and the inability to take account of the chain of events unleashed when a given project is undertaken. The environmental and social costs of forest loss are high; among them is loss of opportunities for sustainable use of the forest, including loss of environmental services such as biodiversity maintenance, water cycling, and carbon storage. The benefits of export infrastructure are meager, especially from the point of view of generating employment. Much of the transportation infrastructure is for soybeans, while the hydroelectric dams contribute to processing aluminum. The example of Avanpa Brasil makes clear the need to rethink how major development decisions are made and to reconsider a number of the plan's component projects. | |||||
BibTeX:
@article{fearnside_avanca_2002, author = {Fearnside, P. M.}, title = {Avanca Brasil: Environmental and social consequences of Brazil's planned infrastructure in Amazonia}, journal = {Environmental Management}, year = {2002}, volume = {30}, number = {6}, pages = {735--747}, note = {Edition: 2002/10/29}, url = {://WOS:000178989200001 http://www.springerlink.com/content/gdww680829d7mdu0/fulltext.pdf}, doi = {https://doi.org/10.1007/s00267-002-2788-2} } |
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Fearnside, P.M. | Environmental impacts of Brazil's Tucurui Dam: Unlearned lessons for hydroelectric development in Amazonia | 2001 | Environmental Management Vol. 27(3), pp. 377-396 |
article | DOI URL |
Abstract: Brazil's Tucurui Dam provides valuable lessons for improving decision-making on major public works in Amazonia and elsewhere. Together with social impacts, which were reviewed in a companion paper, the project's environmental costs are substantial. Monetary costs include costs of construction and maintenance and opportunity costs of natural resources (such as timber) and of the money invested by the Brazilian government. Environmental costs include forest loss, leading to both loss of natural ecosystems and to greenhouse gas emissions. Aquatic ecosystems are heavily affected by the blockage of fish migration and by creation of anoxic environments. Decay of vegetation left in the reservoir creates anoxic water that can corrode turbines, as well as producing methane and providing conditions for methylation of mercury. Defoliants were considered for removing forest in the submergence area but plans were aborted amid a public controversy. Another controversy surrounded impacts of defoliants used to prevent regrowth along the transmission line. Mitigation measures included archaeological and faunal salvage and creation of a "gene bank" on an island in the reservoir. Decision-making in the case of Tucurui was virtually uninfluenced by environmental studies, which were done concurrently with construction. The dam predates Brazil's 1986 requirement of an Environmental Impact Assessment. Despite limitations, research results provide valuable information for future dams. Extensive public-relations use of the research effort and of mitigation measures such as faunal salvage were evident. Decision-making was closely linked to the influence of construction firms, the military, and foreign financial interests in both the construction project and the use of the resulting electrical power (most of which is used for aluminum smelting). Social and environmental costs received virtually no consideration when decisions were made, an outcome facilitated by a curtain of secrecy surrounding many aspects of the project. Despite improvements in Brazil's system of environmental impact assessment since the Tucurui reservoir was filled in 1984, many essential features of the decision-making system remain unchanged. | |||||
BibTeX:
@article{fearnside_environmental_2001, author = {Fearnside, P. M.}, title = {Environmental impacts of Brazil's Tucurui Dam: Unlearned lessons for hydroelectric development in Amazonia}, journal = {Environmental Management}, year = {2001}, volume = {27}, number = {3}, pages = {377--396}, note = {Edition: 2001/01/10}, url = {://WOS:000166573400005}, doi = {https://doi.org/10.1007/s002670010156} } |
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Fearnside, P.M. | Land-tenure issues as factors in environmental destruction in Brazilian Amazonia: The case of Southern Para | 2001 | World Development Vol. 29(8), pp. 1361-1372 |
article | DOI URL |
Abstract: Land-tenure issues have been prominent forces driving deforestation and the spread of extensive ranching as the dominant land use in Brazilian Amazonia. Southern Para is the part of Amazonia where these issues are most explosive, and an examination of this region in terms of its land-tenure issues. their environmental consequences and measures needed provides potentially valuable information for formulating policies that promote more socially and environmentally sound development. The problems of southern Para are likely to spread to increasingly broader sections of Amazonia. The present paper reviews the current land-tenure situation in southern Para and attempts to identify policy changes that would reduce its environmental impact. (C) 2001 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{fearnside_land-tenure_2001, author = {Fearnside, P. M.}, title = {Land-tenure issues as factors in environmental destruction in Brazilian Amazonia: The case of Southern Para}, journal = {World Development}, year = {2001}, volume = {29}, number = {8}, pages = {1361--1372}, url = {://WOS:000170389800005}, doi = {https://doi.org/10.1016/s0305-750x(01)00039-0} } |
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Fearnside, P.M. | Global warming and tropical land-use change: Greenhouse gas emissions from biomass burning, decomposition and soils in forest conversion, shifting cultivation and secondary vegetation | 2000 | Climatic Change Vol. 46(1-2), pp. 115-158 |
article | DOI URL |
Abstract: Tropical forest conversion, shifting cultivation and clearing of secondary vegetation make significant contributions to global emissions of greenhouse gases today, and have the potential for large additional emissions in future decades. Globally, an estimated 3.1x10(9) t of biomass carbon of these types is exposed to burning annually, of which 1.1x10(9) t is emitted to the atmosphere through combustion and 49x10(6) t is converted to charcoal (including 26-31x10(6) t C of black carbon). The amount of biomass exposed to burning includes aboveground remains that failed to burn or decompose from clearing in previous years, and therefore exceeds the 1.9x10(9) t of aboveground biomass carbon cleared on average each year. Above- and belowground carbon emitted annually through decomposition processes totals 2.1x10(9) t C. A total gross emission (including decomposition of unburned aboveground biomass and of belowground biomass) of 3.41x10(9) t C year(-)1 results from clearing primary (nonfallow) and secondary (fallow) vegetation in the tropics. Adjustment for trace gas emissions using IPCC Second Assessment Report 100-year integration global warming potentials makes this equivalent to 3.39x10(9) t of CO(2)-equivalent carbon under a low trace gas scenario and 3.83x10(9) t under a high trace gas scenario. Of these totals, 1.06x10(9) t (31%) is the result of biomass burning under the low trace gas scenario and 1.50x10(9) t (39%) under the high trace gas scenario. The net emissions from all clearing of natural vegetation and of secondary forests (including both biomass and soil fluxes) is 2.0x10(9) t C, equivalent to 2.0-2.4x10(9) t of CO(2)-equivalent carbon. Adding emissions of 0.4x10(9) t C from land-use category changes other than deforestation brings the total for land-use change (not considering uptake of intact forest, recurrent burning of savannas or fires in intact forests) to 2.4x10(9) t C, equivalent to 2.4-2.9x10(9) t of CO(2)-equivalent carbon. The total net emission of carbon from the tropical land uses considered here (2.4x10(9) t C year(-)1) calculated for the 1981-1990 period is 50% higher than the 1.6x10(9) t C year(-)1 value used by the Intergovernmental Panel on Climate Change. The inferred (= `missing') sink in the global carbon budget is larger than previously thought. However, about half of the additional source suggested here may be offset by a possible sink in uptake by Amazonian forests. Both alterations indicate that continued deforestation would produce greater impact on global carbon emissions. The total net emission of carbon calculated here indicates a major global warming impact from tropical land uses, equivalent to approximately 29% of the total anthropogenic emission from fossil fuels and land-use change. | |||||
BibTeX:
@article{fearnside_global_2000, author = {Fearnside, P. M.}, title = {Global warming and tropical land-use change: Greenhouse gas emissions from biomass burning, decomposition and soils in forest conversion, shifting cultivation and secondary vegetation}, journal = {Climatic Change}, year = {2000}, volume = {46}, number = {1-2}, pages = {115--158}, url = {://WOS:000087703900005}, doi = {https://doi.org/10.1023/a:1005569915357} } |
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Fearnside, P.M. | Biodiversity as an environmental service in Brazil's Amazonian forests: risks, value and conservation | 1999 | Environmental Conservation Vol. 26(4), pp. 305-321 |
article | DOI URL |
Abstract: The environmental service provided by the great biodiversity of Amazonian forests is one of several factors leading to the conclusion that much greater efforts are warranted to reduce the destruction of these forests. Risks to biodiversity in Amazonian forests include deforestation, logging, fires, fragmentation, depletion of fauna, invasion by exotic species, and climate change. Financial values assigned to biodiversity depend strongly on the purposes of valuation. Utilitarian benefits include the values of presently-marketed and presently-unexploited forest products, and the monetary value of environmental benefits. Non-monetary values of Amazonian forests are also essential components of decision-making on conservation. Measures of 'willingness to pay' and 'willingness to accept' can be useful as indicators of potential financial flows, but should not be confused with the true values of the forests to society. Valuation for the purpose of setting penalties for destruction of biodiversity is an important legal question in Brazil and must take into consideration additional factors. Conservation of biodiversity in Brazil includes creation of various types of protected areas. The status of these areas varies greatly, with practice frequently deviating front official requirements. Creating reserves that include human occupants has a variety of pros and cons. Although the effect of humans is not always benign, much larger areas can be brought under protection regimes if human occupants are included. Additional considerations apply to buffer zones around protected areas. The choice and design of reserves depends on the financial costs and biodiversity benefits of different strategies. In Brazil, rapid creation of lightly-protected 'paper parks' has been a means of keeping ahead of the advance of barriers to establishment of new conservation units, but emphasis must eventually shift to better protection of existing reserves. Indigenous peoples have the best record of maintaining forest, but negotiation with these peoples is essential in order to ensure maintenance of the large areas of forest they inhabit. The benefits of environmental services provided by the forest must accrue to those who maintain these forests. Development of mechanisms to capture the value of these services will be a key factor affecting the longterm prospects of Amazonian forests. However, many effective measures to discourage deforestation could be taken immediately through government action, including levying and collecting taxes that discourage land speculation, changing land tenure establishment procedures so as not to reward deforestation, revoking remaining incentives, restricting road building and improvement, strengthening requirements for environmental impact statements (RIMAs) for proposed development projects, and creating employment alternatives. | |||||
BibTeX:
@article{fearnside_biodiversity_1999, author = {Fearnside, P. M.}, title = {Biodiversity as an environmental service in Brazil's Amazonian forests: risks, value and conservation}, journal = {Environmental Conservation}, year = {1999}, volume = {26}, number = {4}, pages = {305--321}, url = {://WOS:000085666600009 http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=38505}, doi = {https://doi.org/10.1017/s0376892999000429} } |
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Fearnside, P.M. | Plantation forestry in Brazil: the potential impacts of climatic change | 1999 | Biomass & Bioenergy Vol. 16(2), pp. 91-102 |
article | URL |
Abstract: Most climatic changes predicted to occur in Brazil would reduce yields of silvicultural plantations, mainly through increased frequency and severity of droughts brought on by global warming and by reduction of water vapor sources in Amazonia caused by deforestation. Some additional negative effects could result from changes in temperature, and positive effects could result from CO(2) enrichment. The net effects would be negative, forcing the country to expand plantations onto less-productive land, requiring increased plantation area land consequent economic losses) out of proportion to the climatic change itself. These impacts would affect carbon sequestration and storage consequences of any plans for subsidizing silviculture as a global warming mitigation option. Climate change can be expected to increase the area of plantations needed to supply projected internal demand for and exports of end products from Brazil. June-July-August (dry season) precipitation reductions indicated by simulations reported by the Intergovernmental Panel on Climate Change (IPCC) correspond to rainfall declines in this critical season of approximately 34% in Amazonia, 39% in Southern Brazil and 61% in the Northeast. As an example, if rainfall in Brazilian plantation areas (most of which are now in Southern Brazil) were to decline by 50%, the area needed in 2050 would expand by an estimated 38% over the constant climate case, bringing the total plantation area to 4.5 times the 1991 area. These large areas of additional plantations imply substantial social and environmental impacts. Further addition of plantation area as a global warming response option would augment these impacts, indicating the need for caution in evaluating carbon sequestration proposals. (C) 1999 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{fearnside_plantation_1999, author = {Fearnside, P. M.}, title = {Plantation forestry in Brazil: the potential impacts of climatic change}, journal = {Biomass & Bioenergy}, year = {1999}, volume = {16}, number = {2}, pages = {91--102}, url = {://WOS:000078930500001} } |
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Fearnside, P.M. | Forests and global warming mitigation in Brazil: opportunities in the Brazilian forest sector for responses to global warming under the "clean development mechanism" | 1999 | Biomass & Bioenergy Vol. 16(3), pp. 171-189 |
article | DOI URL |
Abstract: The Kyoto Protocol created global warming response opportunities through the clean development mechanism that allow countries like Brazil to receive investments from companies and governments wishing to offset their emissions of greenhouse gases. Brazil has a special place in strategies for combating global warming because its vast areas of tropical forest represent a potentially large source of emissions if deforested. A number of issues need to be settled to properly assign credit for carbon in the types of options presented by the Brazilian forest sector. These include definition of the units of carbon (permanent sequestration versus carbon-ton-years, the latter being most appropriate for forest options), the means of crediting forest reserve establishment, adoption of discounting or other time-preference weighting for carbon, definition of the accounting method (avoided emissions versus stock maintenance), and mechanisms to allow program contributions to be counted, rather than restricting consideration to free-standing projects. Silvicultural plantations offer opportunities for carbon benefits, but these depend heavily on the end use of the products. Plantations for charcoal have the greatest carbon benefits, but have high social impacts in the Brazilian context. Plantations also inherently compete with deforestation reduction options for funds. Forest management has been proposed as a global warming response option, but the assignment of any value to time makes this unattractive in terms of carbon benefits. However, reduced-impact logging can substantially reduce emissions over those from traditional logging practices. Slowing deforestation is the major opportunity offered by Brazil. Slowing deforestation will require understanding its causes and creating functional models capable of generating land-use change scenarios with and without different policy changes and other activities. Brazil already has a number of programs designed to slow deforestation, but the continued rapid loss of forest highlights the vast gulf that exists between the magnitude of the problem and the efforts to address it. The ups and downs of Brazil's deforestation rate have so far had little to do with deliberate programs to control or influence the process. Achieving this control will require a major effort in which contributions from the private sector will be needed. Mechanisms are needed to make contributions to such programs eligible for carbon credit. (C) 1998 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{fearnside_forests_1999, author = {Fearnside, P. M.}, title = {Forests and global warming mitigation in Brazil: opportunities in the Brazilian forest sector for responses to global warming under the "clean development mechanism"}, journal = {Biomass & Bioenergy}, year = {1999}, volume = {16}, number = {3}, pages = {171--189}, url = {://WOS:000079178100001}, doi = {https://doi.org/10.1016/s0961-9534(98)00071-3} } |
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Fauset, M.O., Gloor, M., Baker, R.T., Monteagudo M., A., Brienen, R.J.W., Feldpausch, T.R., Lopez-Gonsalez, S., Johnson, G., Malhi, H., Pitman, N.C.A., Baraloto, C., Engel, J., Pétronelli, P., Andrade, A., Camargo, J.L.C., Laurence, Y., ter Steege, S. G., W., Laurance, J., Allie, E., Vargas, P.N., Terborgh, J.W., Ruokolainen, K., Silveira, M., Aymard C., G.A., , W.F., Chave, Arroyo, D., Ramirez-Angulo, H., Araujo-Murakami, A., Neill, D., Hérault, B., Dourdain, A., Torres-Lezama, A., , L., Bonal, Marimon, R.P., Comiskey, J.A., Réjou-Méchain, M., Toledo, M., Licona, J.C., Alarcón, A., Prieto, A., Rudas, B.S., Salomão, A., van der Meer, T.J., Marimon Jr., B., Poorter, L., Boot, R.G.A., Stergios, B., Torre, E.V., Costa, F.R.C.C., , P.J., Killeen, Levis, J., Souza, P., Groot, N., Arets, E., Moscoso, V.C., Castro, W., Coronado, E.N.H., Peña-Claros, M., Stahl, C., Schietti, C., Barroso, J., Vieira, I.C.G., van der Heijden, G., Thomas, R., Vos, V.A., Almeida, E.C., Davila, E.A., Aragão L., J., Talbot, E. O., C., Erwin, P.S., Oliveira, E.A., Valadão, M.B.X., Zagt, R.J., van der Hout, P., Loayza, P.A., Pipoly J., T.L., Morandi, J., Wang, M., Cerón, C.E., Huamantupa-Chuquimaco, I., Di Fiore, A., Peacock, J., Camacho, N.C.P., Umetsu R., O., Alexiades, K., Camargo, R.J., Herrera, R., Quesada, C.A., Stropp, J., Vieira, S.A., Steininger, M., Rodríguez, C.R., , P.B., Burnham, Restrepo, A.E., Lewis, S.L., Pickavance G. C. & Phillips, O.L.Z. and Muelbert | Hyperdominance in Amazonian forest carbon cycling [BibTeX] |
2015 | Nature Communications Vol. 13(16), pp. 1-9 |
article | |
BibTeX:
@article{fauset_hyperdominance_2015, author = {Fauset, M. O.; Gloor, M.; Baker, R. T.; Monteagudo M., A.; Brienen, R. J. W.; Feldpausch, T. R.; Lopez-Gonsalez, , S.; Johnson and G.; Malhi, H.; Pitman, N. C. A.; Baraloto, C.; Engel, J.; Pétronelli, P.; Andrade, A.; Camargo, J. L. C.; Laurence, , Y.; ter Steege and S. G. W.; Laurance, J.; Allie, E.; Vargas, P. N.; Terborgh, J. W.; Ruokolainen, K.; Silveira, M.; Aymard C., G. A.;, W. F.; Chave and Arroyo, D.; Ramirez-Angulo, H.; Araujo-Murakami, A.; Neill, D.; Hérault, B.; Dourdain, A.; Torres-Lezama, A.;, L.; Bonal and Marimon, R. P.; Comiskey, J. A.; Réjou-Méchain, M.; Toledo, M.; Licona, J. C.; Alarcón, A.; Prieto, A.; Rudas, , B. S.; Salomão and A.; van der Meer, T. J.; Marimon Jr., B.; Poorter, L.; Boot, R. G. A.; Stergios, B.; Torre, E. V.; Costa, F. R. C. C.;, P. J.; Killeen and Levis, J.; Souza, P.; Groot, N.; Arets, E.; Moscoso, V. C.; Castro, W.; Coronado, E. N. H.; Peña-Claros, M.; Stahl, , C.; Schietti and C.; Barroso, J.; Vieira, I. C. G.; van der Heijden, G.; Thomas, R.; Vos, V. A.; Almeida, E. C.; Davila, E. A.; Aragão, L., J.; Talbot and E. O. C.; Erwin, P. S.; Oliveira, E. A.; Valadão, M. B. X.; Zagt, R. J.; van der Hout, P.; Loayza, P. A.; Pipoly, J., T. L.; Morandi and J.; Wang, M.; Cerón, C. E.; Huamantupa-Chuquimaco, I.; Di Fiore, A; Peacock, J.; Camacho, N. C. P.; Umetsu, R., O.; Alexiades and K.; Camargo, R. J.; Herrera, R.; Quesada, C. A.; Stropp, J.; Vieira, S. A.; Steininger, M.; Rodríguez, C. R.;, P. B.; Burnham and Restrepo, A. E.; Lewis, S. L.; Pickavance, G. C. & Phillips, O. L., Z.; Muelbert}, title = {Hyperdominance in Amazonian forest carbon cycling}, journal = {Nature Communications}, year = {2015}, volume = {13}, number = {16}, pages = {1--9} } |
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Farella, N., Lucotte, M., Louchouarn, P. and Roulet, M. | Deforestation modifying terrestrial organic transport in the Rio Tapajos, Brazilian Amazon | 2001 | Organic Geochemistry Vol. 32(12), pp. 1443-1458 |
article | DOI URL |
Abstract: The concentration and biomarker compositions of sedimentary organic matter (OM) as well as fine and coarse suspended particles were analysed to identify the impact of deforestation on the transport of terrigenous organic matter (OM) in the Rio Tapajos, a major tributary to the Amazon. Substantial shifts in the concentration and composition of recently deposited sedimentary OM suggest that intensive deforestation over the last few decades has considerably modified the natural inputs of sedimentary materials to the aquatic ecosystems by disrupting the terrigenous fluxes of humus and soil materials from the drainage basin. The observed compositional changes of bulk OM and land derived biomarkers (e.g. lignin) in recent sediments illustrate a sedimentary enrichment in OM from soil horizons that, under normal forest cover, tend to be retained in the drainage basin. On average, the recently accumulated OM is nitrogen-rich ((C/N)a = 12-15) and more highly degraded ((Ac/Al)v = 0.4-0.6 and DHBA/V = 0.15-0.20) than deep materials ((C/N)a = 20-30, (Ac/Al)v = 0.25-0.4, and DHBA/V = 0.05-0.10), showing that this recently accumulated material is more humified than original inputs to the aquatic system, and consistent with increased exportation of fine eroded mineral and organic particles from surface soils along river banks. The present study illustrates the relevance of using OM oxidation products in sediment profiles to evaluate deforestation impacts on aquatic ecosystems and to characterize the nature of eroded soil materials, complementing studies on mineral/metal cycling. (C) 2001 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{farella_deforestation_2001, author = {Farella, N. and Lucotte, M. and Louchouarn, P. and Roulet, M.}, title = {Deforestation modifying terrestrial organic transport in the Rio Tapajos, Brazilian Amazon}, journal = {Organic Geochemistry}, year = {2001}, volume = {32}, number = {12}, pages = {1443--1458}, url = {://WOS:000172937800006}, doi = {https://doi.org/10.1016/s0146-6380(01)00103-6} } |
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Fang, Y., Leung, L., Duan, Z., Wigmosta, M., Maxwell, R., Chambers, J. and Tomasella, J. | Influence of landscape heterogeneity on water available to tropical forests in an Amazonian catchment and implications for modeling drought response [BibTeX] |
2017 | J. Geophys. Res. Atmos. Vol. 122 |
article | DOI |
BibTeX:
@article{fang_influence_2017, author = {Fang, Y. and Leung, L.R. and Duan, Z. and Wigmosta, M.S. and Maxwell, R.M. and Chambers, J.Q. and Tomasella, J.}, title = {Influence of landscape heterogeneity on water available to tropical forests in an Amazonian catchment and implications for modeling drought response}, journal = {J. Geophys. Res. Atmos.}, year = {2017}, volume = {122}, doi = {https://doi.org/10.1002/2017JD027066} } |
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Fan, J., Rosenfeld, D., Zhang, Y., Giangrande, S., Li, Z., Machado, L.A.T., Martin, S.T., Yang, Y., Wang, J., Artaxo, P., Barbosa, H.J. and Ramon C. Braga Zhe Feng, W.G.H.B.G.F.M.C.P.M.L.P.U.P.R.A.F.d.S.J.M.C. | Substantial Convection and Precipitation Enhancement by Ultrafine Aerosol Particles [BibTeX] |
2018 | Science Vol. 359(6374) |
article | |
BibTeX:
@article{fan_substantial_2018, author = {Fan, J. and Rosenfeld, D. and Zhang, Y. and Giangrande, S. and Li, Z. and Machado, L. A. T. and Martin, S. T. and Yang, Y. and Wang, J. and Artaxo, P. and Barbosa, H.M. J. and Ramon C. Braga, Zhe Feng, Wenhua Gao, Helber B. Gomes, Fan Mei, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Rodrigo A. F. de Souza, Jennifer M. Comstock}, title = {Substantial Convection and Precipitation Enhancement by Ultrafine Aerosol Particles}, journal = {Science}, year = {2018}, volume = {359}, number = {6374} } |
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Falkovich, A.H., Graber, E.R., Schkolnik, G., Rudich, Y., Maenhaut, W. and Artaxo, P. | Low molecular weight organic acids in aerosol particles from Rondonia, Brazil, during the biomass-burning, transition and wet periods | 2005 | Atmospheric Chemistry and Physics Vol. 5, pp. 781-797 |
article | URL |
Abstract: Particles from biomass burning and regional haze were sampled in Rondonia, Brazil, during dry, transition and wet periods from September to November 2002, as part of the LBA-SMOCC (Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Smoke, Aerosols, Clouds, Rainfall, and Climate) field campaign. Water soluble organic and inorganic compounds in bulk (High Volume and Stacked Filter Unit sampler) and size-resolved (Micro Orifice Uniform Deposit Impactor - MOUDI) smoke samples were determined by ion chromatography. It was found that low molecular weight polar organic acids account for a significant fraction of the water soluble organic carbon (WSOC) in biomass burning aerosols (C-2-C-6 dicarboxylic acids reached up to 3.7% and one-ring aromatic acids reached up to 2% of fine fraction WSOC during burning period). Short dicarboxylic (C-2-C-6) acids are dominated by oxalic acid followed by malonic and succinic acids. The largest ionic species is ammonium sulfate (60-70% of ionic mass). It was found that most of the ionic mass is concentrated in submicrometer-sized particles. Based on the size distribution and correlations with K+, a known biomass burning tracer, it is suggested that many of the organic acids are directly emitted by vegetation fires. Concentrations of dicarboxylic acids in the front and back filters of high volume sampler were determined. Based on these measurements, it was concluded that in the neutral or slightly basic smoke particles typical of this region, dicarboxylic acids are mostly confined to the particulate phase. Finally, it is shown that the distribution of water soluble species shifts to larger aerosols sizes as the aerosol population ages and mixes with other aerosol types in the atmosphere. | |||||
BibTeX:
@article{falkovich_low_2005, author = {Falkovich, A. H. and Graber, E. R. and Schkolnik, G. and Rudich, Y. and Maenhaut, W. and Artaxo, P.}, title = {Low molecular weight organic acids in aerosol particles from Rondonia, Brazil, during the biomass-burning, transition and wet periods}, journal = {Atmospheric Chemistry and Physics}, year = {2005}, volume = {5}, pages = {781--797}, url = {://WOS:000227539100002} } |
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Luizão., F.J. | O Projeto Cenários para a Amazônia: programas associados, metas e síntese de atuação [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 7-15 |
incollection | |
BibTeX:
@incollection{emilio_o_2014, author = {F.J., Luizão.}, title = {O Projeto Cenários para a Amazônia: programas associados, metas e síntese de atuação}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {7--15}, note = {Section: 1} } |
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Ewers, R.M., Laurance, W.F. and Souza Jr., C.M. | Temporal fluctuations in Amazonian deforestation rates | 2008 | Environmental Conservation Vol. 35(4), pp. 303-310 |
article | DOI URL |
Abstract: Tropical deforestation is one of the most important components of global change. Rates of deforestation in Brazil, the nation with the single largest concentration of tropical forest on Earth, have fluctuated widely over the last twenty years. Based on local knowledge, such fluctuations have been variously attributed to a wide range of factors such as the expansion of cattle ranching and soybean farming, infrastructural expansion and the proliferation of paved and unpaved roads, macroeconomic shocks to the Brazilian economy and international exchange rates. Many, if not all, of these arguments are plausible explanations for temporal variation in deforestation rates, but have to date not been subjected to rigorous statistical testing; this study investigates the potential impact of these variables on Brazilian tropical deforestation over the period 1990-2005. When analysed at the basin-wide scale, nearly all variables were highly inter-correlated through time and were also closely correlated with deforestation rate, but appropriate time-series analysis found no statistical evidence that any of the variables have systematically caused variation in deforestation rates. Power analysis showed that the variables may exert small or medium influences on deforestation rates, but the impacts, if present, are not strong. Future analyses of time series data at finer spatial scales that exploit spatiotemporal variation in deforestation rates and in the hypothesized predictor variables may find significant causal processes that arc overlooked when analysed at the basin-wide scale. | |||||
BibTeX:
@article{ewers_temporal_2008, author = {Ewers, Robert M. and Laurance, William F. and Souza, Jr., Carlos M.}, title = {Temporal fluctuations in Amazonian deforestation rates}, journal = {Environmental Conservation}, year = {2008}, volume = {35}, number = {4}, pages = {303--310}, url = {://WOS:000264045600004}, doi = {https://doi.org/10.1017/s0376892908005122} } |
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Ewers, R.M. and Laurance, W.F. | Scale-dependent patterns of deforestation in the Brazilian Amazon | 2006 | Environmental Conservation Vol. 33(3), pp. 203-211 |
article | DOI URL |
Abstract: Tropical forests of the Amazon Basin are being rapidly converted to agricultural land uses and fallow land, resulting in accelerating rates of forest loss in one of the world's most biodiverse ecoregions. This process has been extensively described and modelled, but as yet there has been no formal test of how the spatial patterns of deforested and fragmented areas change with the spatial scale of forest clearings. It was hypothesised that different land-use practices are driving small and large clearings, with small-scale cultivators often creating small, irregularly shaped clearings and large-scale ranchers and soy farmers creating larger, more regular-shaped clearings. To quantitatively test this hypothesis, Mandelbrot's theory of fractals was applied to deforested areas in the Brazilian Amazon to test for scale-invariance in deforestation patterns. The spatial pattern of deforestation differed between small and large clearings, with the former creating more complex landscapes and with a threshold occurring at c. 1200 ha in area. As a consequence, the sizes and shapes of forest clearings, and hence the relative vulnerability of the remaining forest to edge, area and isolation effects, may differ systematically between landscapes with different deforestation drivers. Further tests of this hypothesis are needed to assess its efficacy in other tropical landscapes and geographical locations. | |||||
BibTeX:
@article{ewers_scale-dependent_2006, author = {Ewers, Robert M. and Laurance, William F.}, title = {Scale-dependent patterns of deforestation in the Brazilian Amazon}, journal = {Environmental Conservation}, year = {2006}, volume = {33}, number = {3}, pages = {203--211}, url = {://WOS:000241962600005}, doi = {https://doi.org/10.1017/s0376892906003250} } |
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Ewers, R.M., Andrade, A., Laurance, S., Camargo, J.L.C., Lovejoy, T. and Laurance, W. | Predicted trajectories of tree community change in Amazonian rainforest fragments [BibTeX] |
2016 | Ecography Vol. 39, pp. 1-10 |
article | DOI |
BibTeX:
@article{ewers_predicted_2016, author = {Ewers, R. M. and Andrade, A. and Laurance, S. and Camargo, J. L. C. and Lovejoy, T. and Laurance, W}, title = {Predicted trajectories of tree community change in Amazonian rainforest fragments}, journal = {Ecography}, year = {2016}, volume = {39}, pages = {1--10}, doi = {https://doi.org/10.1111/ecog.02585} } |
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Evans, T.P. and Moran, E.F. | Spatial integration of social and biophysical factors related to landcover change [BibTeX] |
2002 | Population and Development Review Vol. 28, pp. 165-186 |
article | URL |
BibTeX:
@article{evans_spatial_2002, author = {Evans, Tom P. and Moran, Emilio F.}, title = {Spatial integration of social and biophysical factors related to landcover change}, journal = {Population and Development Review}, year = {2002}, volume = {28}, pages = {165--186}, url = {://WOS:000202895700008} } |
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Evans, T.P., Manire, A., de Castro, F., Brondizio, E. and McCracken, S. | A dynamic model of household decision-making and parcel level landcover change in the eastern Amazon | 2001 | Ecological Modelling Vol. 143(1-2), pp. 95-113 |
article | DOI URL |
Abstract: The region around Altamira, Brazil, located in the Eastern Amazon, has experienced rapid landcover change since the initiation of government sponsored colonization projects associated with the construction of the Trans-Amazon Highway. The 30 years since colonization (1971) have been marked by a net loss of forest cover and an increase in the amount of cultivated/productive land, particularly for pasture and annual/perennial crop production. This research presents a parcel-level model of landcover change for smallholders in the Altamira study area. The utility of specific land-use activities is calculated to identify those land-uses that are most optimal at each time point, and labor is allocated to these activities based on the availability of household and wage labor. The model reports the proportion of the parcel in the following landcover classes at each time point using a 1-year interval: mature forest, secondary successional forest, perennial crops, annual crops and pasture. A graphical user interface is used for scenario testing, such as the impact of high/low (population) fertility, the increase of out-migration to urban areas, or changes in cattle and crop prices. The model shows a rapid reduction in the amount of mature forest in the 30 years following initial settlement, after which the parcel is composed of a mosaic of secondary succession, pasture and crops. The nature and rapidity of this landcover change is the function of a variety of household and external variables incorporated in the model. In particular, the model produces different landcover compositions as a function of demographic rates (fertility, mortality) and agricultural prices. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{evans_dynamic_2001, author = {Evans, T. P. and Manire, A. and de Castro, F. and Brondizio, E. and McCracken, S.}, title = {A dynamic model of household decision-making and parcel level landcover change in the eastern Amazon}, journal = {Ecological Modelling}, year = {2001}, volume = {143}, number = {1-2}, pages = {95--113}, url = {://WOS:000171505500008}, doi = {https://doi.org/10.1016/s0304-3800(01)00357-x} } |
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Esquivel-Muelbert, A., Galbraith, D., Dexter, K.G., Baker, T.R., Lewis, S.L., Meir, P., Rowland, L., Costa, A.C.L.d., Nepstad, D. and Phillips, O.L. | Biogeographic distributions of neotropical trees reflect their directly measured drought tolerances [BibTeX] |
2017 | Scientific Reports Vol. 7, pp. 8334 |
article | DOI |
BibTeX:
@article{esquivel-muelbert_biogeographic_2017, author = {Esquivel-Muelbert, Adriane and Galbraith, David and Dexter, Kyle G. and Baker, Timothy R. and Lewis, Simon L. and Meir, Patrick and Rowland, Lucy and Costa, Antonio Carlos Lola da and Nepstad, Daniel and Phillips, Oliver L.}, title = {Biogeographic distributions of neotropical trees reflect their directly measured drought tolerances}, journal = {Scientific Reports}, year = {2017}, volume = {7}, pages = {8334}, doi = {https://doi.org/10.1038/s41598-017-08105-8} } |
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Esquivel Muelbert, A., Baker, T., R. Dexter, K., G. Lewis, S., L. Brienen, Roel J., W., Feldpausch, T.R., Lloyd, J., Monteagudo Mendoza, A., Arroyo, L., Álvarez-Dávila, E., Higuchi, N. and Marimon Ben Hur Silveira, M.V.E.G.E.M.Y.C.J.B.J.B.D.D.C.N.E.T.F.S.H.B.L.S.e.a.B.s.M.-J. | Compositional response of Amazon forests to climate change [BibTeX] |
2019 | Global Change Biology Vol. 25, pp. 39-56 |
article | |
BibTeX:
@article{esquivel_muelbert_compositional_2019, author = {Esquivel Muelbert, Adriane and Baker, Timothy and R. Dexter, Kyle and G. Lewis, Simon and L. Brienen and W., Roel J. and Feldpausch, Ted R. and Lloyd, Jon and Monteagudo Mendoza, Abel and Arroyo, Luzmila and Álvarez-Dávila, Esteban and Higuchi, Niro and Marimon, Ben Hur Silveira, Marcos Vilanova, Emilio Gloor, Emanuel Malhi, Yadvinder Chave, Jerôme Barlow, Jos Bonal, Damien Davila Cardozo, Nallaret Erwin, Terry Fauset, Sophie Hérault, Bruno Laurance, Susan, et al., Beatriz s. Marimon-Junior}, title = {Compositional response of Amazon forests to climate change}, journal = {Global Change Biology}, year = {2019}, volume = {25}, pages = {39--56} } |
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Espirto-Santo, F.D.B., Shimabukuro, Y.E. and Kuplich, T.M. | Mapping forest successional stages following deforestation in Brazilian Amazonia using multi-temporal Landsat images | 2005 | International Journal of Remote Sensing Vol. 26(3), pp. 635-642 |
article | DOI URL |
Abstract: Tropical forest successional stages have been mapped previously with multi-temporal satellite sensor imagery. The precise identification and classification of such stages, however, has proved difficult. This Letter presents a new method for the classification of forest successional stages following deforestation in Brazilian Amazonia. Multi-temporal Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) and derived fraction images and field data were used in a semi-automatic classification approach. The results were encouraging and signal the application of the method for the entire Brazilian Amazonia. | |||||
BibTeX:
@article{espirto-santo_mapping_2005, author = {Espirto-Santo, F. D. B. and Shimabukuro, Y. E. and Kuplich, T. M.}, title = {Mapping forest successional stages following deforestation in Brazilian Amazonia using multi-temporal Landsat images}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {3}, pages = {635--642}, url = {://WOS:000226835700015}, doi = {https://doi.org/10.1080/0143116042000274078} } |
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Espírito-Santo, F., Keller, M., Linder, E., Oliveira Junior, R., Pereira, C. and Oliveira, C. | Gap formation and carbon cycling in the Brazilian Amazon: measurement using high-resolution optical remote sensing and studies in large forest plots [BibTeX] |
2014 | Plant Ecology & Diversity (Print) Vol. 7(1-2), pp. 305-318 |
article | |
BibTeX:
@article{espirito-santo_gap_2014, author = {Espírito-Santo, F.D.B. and Keller, M.M. and Linder, E. and Oliveira Junior, R.C. and Pereira, Cleuton and Oliveira, C.G.}, title = {Gap formation and carbon cycling in the Brazilian Amazon: measurement using high-resolution optical remote sensing and studies in large forest plots}, journal = {Plant Ecology & Diversity (Print)}, year = {2014}, volume = {7}, number = {1-2}, pages = {305--318} } |
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Espirito-Santo, F.D.B., Keller, M., Braswell, B., Nelson, B.W., Frolking, S. and Vicente, G. | Storm intensity and old-growth forest disturbances in the Amazon region | 2010 | Geophysical Research Letters Vol. 37 |
article | DOI URL |
Abstract: We analyzed the pattern of large forest disturbances or blow-downs apparently caused by severe storms in a mostly unmanaged portion of the Brazilian Amazon using 27 Landsat images and daily precipitation estimates from NOAA satellite data. For each Landsat a spectral mixture analysis (SMA) was applied. Based on SMA, we detected and mapped 279 patches (from 5 ha to 2,223 ha) characteristic of blow-downs. A total of 21,931 ha of forest were disturbed. We found a strong correlation between occurrence of blow-downs and frequency of heavy rainfall (Spearman's rank, r(2) = 0.84, p textless 0.0003). The recurrence intervals of large disturbances were estimated to be 90,000 yr for the eastern Amazon and 27,000 yr for the western Amazon. This suggests that weather patterns affect the frequency of large forest disturbances that may produce different rates of forest turnover in the eastern and western Amazon basin. Citation: Esp rito-Santo, F. D. B., M. Keller, B. Braswell, B. W. Nelson, S. Frolking, and G. Vicente (2010), Storm intensity and old-growth forest disturbances in the Amazon region, Geophys. Res. Lett., 37, L11403, doi:10.1029/2010GL043146. | |||||
BibTeX:
@article{espirito-santo_storm_2010, author = {Espirito-Santo, F. D. B. and Keller, M. and Braswell, B. and Nelson, B. W. and Frolking, S. and Vicente, G.}, title = {Storm intensity and old-growth forest disturbances in the Amazon region}, journal = {Geophysical Research Letters}, year = {2010}, volume = {37}, url = {://WOS:000278453100002}, doi = {https://doi.org/10.1029/2010gl043146} } |
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Espírito-Santo, F., Gloor, M., Keller, M., Malhi, Y., Saatchi, S., Nelson, B., Junior, R., Pereira, C., Lloyd, J., Frolking, S., Palace, M., Shimabukuro, Y., Duarte, V., Mendoza, A., López-González, G., Baker, T., Feldpausch, T., Brienen J.W., R., Asner, G., Boyd, D. and Phillips, O. | Size and frequency of natural forest disturbances and the Amazon forest carbon balance [BibTeX] |
2014 | Nature Communications Vol. 5, pp. 3434, |
article | |
BibTeX:
@article{espirito-santo_size_2014, author = {Espírito-Santo, F.D.B. and Gloor, M. and Keller, M. and Malhi, Y. and Saatchi, S and Nelson, B. and Junior, R.C.O. and Pereira, C. and Lloyd, J. and Frolking, S. and Palace, M. and Shimabukuro, Y.E. and Duarte, V. and Mendoza, A.M. and López-González, G. and Baker, T.R. and Feldpausch, T.R. and Brienen, J.W., R and Asner, G.P. and Boyd, D.S. and Phillips, O.L.}, title = {Size and frequency of natural forest disturbances and the Amazon forest carbon balance}, journal = {Nature Communications}, year = {2014}, volume = {5}, pages = {3434,} } |
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Espírito-Santo Shimabukuro, Y. and Aragão L.E.O.C. & Machado, E.F. | Análise da composição florística e fitossociológica da floresta nacional do Tapajós com o apoio geográfico de imagens de satélites [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 155 - 173 |
article | |
BibTeX:
@article{espirito-santo_alise_2005, author = {Espírito-Santo, Shimabukuro, Y.E.; Aragão, L.E.O.C. & Machado, E.L.M., F.D.B.}, title = {Análise da composição florística e fitossociológica da floresta nacional do Tapajós com o apoio geográfico de imagens de satélites}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {155 -- 173} } |
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Espindola, G.M.d., Aguiar, A.P., Pebesma, E., Câmara, G. and Fonseca, L. | Agricultural land use dynamics in the Brazilian Amazon based on remote sensing and census data [BibTeX] |
2012 | Applied Geography Vol. 32(2), pp. 240-252 |
article | |
BibTeX:
@article{espindola_agricultural_2012, author = {Espindola, Giovana M. de and Aguiar, Ana Paula and Pebesma, Edzer and Câmara, Gilberto and Fonseca, Leila}, title = {Agricultural land use dynamics in the Brazilian Amazon based on remote sensing and census data}, journal = {Applied Geography}, year = {2012}, volume = {32}, number = {2}, pages = {240--252} } |
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Escada, M.I.S., Lobo, F.d.L., Gavlak, A.A., Saito, É.A., Pinheiro, T.d.F., Silva, M., Almeida, C.A. and Azeredo, M. | Padrões espaço-temporais de uso e cobertura da terra nas Áreas de Endemismo Xingu e Tapajós [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 67-78 |
incollection | |
BibTeX:
@incollection{emilio_padroes_2014, author = {Escada, Maria Isabel Sobral and Lobo, Felipe de Lucia and Gavlak, André Augusto and Saito, Érika Akemi and Pinheiro, Taise de Farias and Silva, Maurício and Almeida, Cláudio Aparecido and Azeredo, Márcio}, title = {Padrões espaço-temporais de uso e cobertura da terra nas Áreas de Endemismo Xingu e Tapajós}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {67--78}, note = {Section: 6} } |
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Erickson, H., Keller, M. and Davidson, E.A. | Nitrogen oxide fluxes and nitrogen cycling during postagricultural succession and forest fertilization in the humid tropics | 2001 | Ecosystems Vol. 4(1), pp. 67-84 |
article | DOI URL |
Abstract: The effects of changes in tropical land use on soil emissions of nitrous oxide (N(2)O) and nitric oxide (NO) are not well understood. We examined emissions of N(2)O and NO and their relationships to land use and forest composition, litterfall, soil nitrogen (N) pools and turnover, soil moisture, and patterns of carbon (C) cycling in a lower montane, subtropical wet region of Puerto Rico. Fluxes of N(2)O and NO were measured monthly for over 1 year in old (more than 60 years old) pastures, early- and mid-successional forests previously in pasture, and late-successional forests not known to have been in pasture within the tabonuco (Dacryodes excelsa) forest zone. Additional, though less frequent, measures were also made in an experimentally fertilized tabonuco forest. N(2)O fluxes exceeded NO fluxes at all sites, reflecting the consistently wet environment. The fertilized forest had the highest N oxide emissions (22.0 kg . N . ha(-1) . y(-1)). Among the unfertilized sites, the expected pattern of increasing emissions with stand age did not occur in all cases. The mid-successional forest most dominated by leguminous trees had the highest emissions (9.0 kg N . ha(-1) . y(-1)), whereas the mid-successional forest lacking legumes had the lowest emissions (0.09 kg N . ha(-1) . y(-1)). N oxide fluxes from late-successional forests were higher than fluxes from pastures. Annual N oxide fluxes correlated positively to leaf litter N, net nitrification potential nitrification, soil nitrate, and net N mineralization and negatively to leaf litter C:N ratio. Soil ammonium was not related to N oxide emissions. Forests with lower fluxes of N oxides had higher rates of C mineralization than sites with higher N oxide emissions. We conclude that (a) N oxide fluxes were substantial where the availability of inorganic N exceeded the requirements of competing biota; (b) species composition resulting from historical land use or varying successional dynamics played an important role in determining N availability; and (c) the established ecosystem models that predict N oxide loss from positive relationships with soil ammonium may need to be modified. | |||||
BibTeX:
@article{erickson_nitrogen_2001, author = {Erickson, H. and Keller, M. and Davidson, E. A.}, title = {Nitrogen oxide fluxes and nitrogen cycling during postagricultural succession and forest fertilization in the humid tropics}, journal = {Ecosystems}, year = {2001}, volume = {4}, number = {1}, pages = {67--84}, url = {://WOS:000167550100006}, doi = {https://doi.org/10.1007/s100210000060} } |
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Erickson, H., Davidson, E.A. and Keller, M. | Former land-use and tree species affect nitrogen oxide emissions from a tropical dry forest | 2002 | Oecologia Vol. 130(2), pp. 297-308 |
article | DOI URL |
Abstract: Species composition in successional dry forests in the tropics varies widely, but the effect of this variation on biogeochemical processes is not well known. We examined fluxes of N oxides (nitrous and nitric oxide), soil N cycling, and litter chemistry (C/N ratio) in four successional dry forests on similar soils in western Puerto Rico with differing species compositions and land-use histories. Forests patch-cut for charcoal 60 years ago had few legumes, high litter C/N ratios, low soil nitrate and low N oxide fluxes. In contrast, successional forests from pastures abandoned several decades ago had high legume densities, low litter C/N ratios, high mean soil nitrate concentrations and high N oxide fluxes. These post-pasture forests were dominated by the naturalized legume Leuceana leucocephala, which was likely responsible for the rapid N cycling in those forests. We conclude that agriculturally induced successional pathways leading to dominance by a legume serve as a mechanism for increasing N oxide emissions from tropical regions. As expected for dry regions, nitric oxide dominated total N oxide emissions. Nitric oxide emissions increased with increasing soil moisture up to about 30% water-filled pore space then stabilized, while nitrous oxide emissions, albeit low, continued to increase with increasing soil wetness. Inorganic N pools and net N mineralization were greatest during peak rainfalls and at the post-agricultural site with the highest fluxes. Soil nitrate and the nitrate/ammonium ratio correlated positively with average N oxide fluxes. N oxide fluxes were negatively and exponentially related to litter C/N ratio for these dry forests and the relationship was upheld with the addition of data from seven wet forests in northeastern Puerto Rico. This finding suggests that species determination of litter C/N ratio may partly determine N oxide fluxes across widely differing tropical environments. | |||||
BibTeX:
@article{erickson_former_2002, author = {Erickson, H. and Davidson, E. A. and Keller, M.}, title = {Former land-use and tree species affect nitrogen oxide emissions from a tropical dry forest}, journal = {Oecologia}, year = {2002}, volume = {130}, number = {2}, pages = {297--308}, url = {://WOS:000173912100017}, doi = {https://doi.org/10.1007/s004420100801} } |
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Engle, D. and Melack, J.M. | Methane emissions from an Amazon floodplain lake: Enhanced release during episodic mixing and during falling water | 2000 | Biogeochemistry Vol. 51(1), pp. 71-90 |
article | DOI URL |
Abstract: Methane fluxes to the troposphere were measured in Lake Calado, a dendritic floodplain lake located in the central Amazon Basin. Methane concentrations in the surface water of the lake were less than 0.5 mu M during a period of high and rising water in April and May, except when episodic, deep mixing occurred and surficial concentrations reached as high as 4.8 mu M. Diffusive fluxes ranged from ca. 2-20 mg CH4 m(-2)d(-1) (mean: 6.6 mg CH4 m(-2)d(-1)) normally, but increased up to 220 mg CH4 m(-2)d(-1) during the passage of a rare cold front. During six weeks of rising water, the volume-weighted methane content of the lake increased during periods of stable thermal stratification (accumulation rates ranging from 16-1411 mg CH4 m(-2)d(-1)) and decreased during episodes of partial mixing (rates of decrease ranging from 63-1792 mg CH4 m(-2)d(-1)). Surface water methane concentrations during low and falling water in September varied by more than an order of magnitude (range, 0.3-9 mu M), and diffusive fluxes ranged from 3-158 mg CH4 m(-2)d(-1) (mean, 54 mg CH4 m(-2)d(-1)). During falling water in September, total methane flux from the lake to the troposphere measured with a floating chamber ranged from 53-328 mg CH4 m(-2)d(-1) (mean, 163 mg CH4 m(-2)d(-1)). Ebullitive flux averaged 69% of total flux. Total methane flux was highest when thermal stratification was lost due to decreasing lake depth. | |||||
BibTeX:
@article{engle_methane_2000, author = {Engle, D. and Melack, J. M.}, title = {Methane emissions from an Amazon floodplain lake: Enhanced release during episodic mixing and during falling water}, journal = {Biogeochemistry}, year = {2000}, volume = {51}, number = {1}, pages = {71--90}, url = {://WOS:000088074800003}, doi = {https://doi.org/10.1023/a:1006389124823} } |
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Emmert, L., Negrón-Juárez, R., Chambers, J., Santos, J., Lima, A., Trumbore, S. and Magnabosco Marra, D. | Sensitivity of Optical Satellites to Estimate Windthrow Tree-Mortality in a Central Amazon Forest [BibTeX] |
2023 | PRE PRINT Vol. PRE PRINT |
article | DOI |
BibTeX:
@article{emmert_sensitivity_2023, author = {Emmert, Luciano and Negrón-Juárez, Robinson and Chambers, Jeffrey and Santos, Joaquim and Lima, Adriano and Trumbore, Susan and Magnabosco Marra, Daniel}, title = {Sensitivity of Optical Satellites to Estimate Windthrow Tree-Mortality in a Central Amazon Forest}, journal = {PRE PRINT}, year = {2023}, volume = {PRE PRINT}, doi = {https://doi.org/10.20944/preprints202305.1631.v1} } |
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Emilio, T., Souza, F.C.d., Naman, L., Holanda, A.S.S.d., Nagy, L. and Magnusson, W.E. | Formação e fixação de recursos humanos na Amazônia [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 163-176 |
incollection | |
BibTeX:
@incollection{emilio_formacao_2014, author = {Emilio, Thaise and Souza, Fernanda Coelho de and Naman, Livia and Holanda, Ana Sofia Souza de and Nagy, Laszlo and Magnusson, William E.}, title = {Formação e fixação de recursos humanos na Amazônia}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {163--176}, note = {Section: 14} } |
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Emilio, T., Quesada, C.A., Costa, F.R. and William E. Magnusson Ted R. Feldpausch, R.J.B.T.R.B.J.C.E.Á.A.A.O.B.C.V.C.E.N.H.C.T.J.K.Y.M.E.M.O.M.A.M.D.N.G.A.P.A.P.-C.H.R.-A.M.S.M.S.H.t.S.J.W.T.R.T.A.T.-L.E.V.&.O.L.P.J.S. | Soil physical conditions limit palm and tree basal area in Amazonian forests [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 215-229 |
article | |
BibTeX:
@article{emilio_soil_2014, author = {Emilio, Thaise and Quesada, Carlos A. and Costa, Flávia R.C. and William E. Magnusson, Ted R. Feldpausch, Roel J.W. Brienen, Timothy R. Baker, Jerome Chave, Estebán Álvarez, Alejandro Araújo, Olaf Bánki, Carolina V. Castilho, Eurídice N. Honorio C., Timothy J. Killeen, Yadvinder Malhi, Erick M. Oblitas Mendoza, Abel Monteagudo, David Neill, Germaine Alexander Parada, Antonio Peña-Cruz, Hirma Ramirez-Angulo, Michael Schwarz, Marcos Silveira, Hans ter Steege, John W. Terborgh, Raquel Thomas, Armando Torres-Lezama, Emilio Vilanova & Oliver L. Phillips, Juliana Schietti}, title = {Soil physical conditions limit palm and tree basal area in Amazonian forests}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {215--229} } |
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Emilio, T. and Luizão, F. | Cenários para a Amazônia: clima, biodiversidade e uso da terra [BibTeX] |
2014 | Vol. 1(1) |
book | |
BibTeX:
@book{emilio_cenarios_2014-1, author = {Emilio, Thaise and Luizão, Flávio}, title = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, note = {Section: 191p} } |
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El-Masri, B., Barman, R., Meiyappan, P., Song, Y., Liang, M. and Jain, A. | Carbon dynamics in the Amazonian Basin: Integration of eddy covariance and ecophysiological data with a land surface model. [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183(15 December 2013), pp. 156-167 |
article | |
BibTeX:
@article{el-masri_carbon_2013, author = {El-Masri, B. and Barman, R. and Meiyappan, P. and Song, Y. and Liang, M. and Jain, A.K.}, title = {Carbon dynamics in the Amazonian Basin: Integration of eddy covariance and ecophysiological data with a land surface model.}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, number = {15 December 2013}, pages = {156--167} } |
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Ellis, E., Richey, J., Aufdenkampe, A., Krusche, A., Quay, P., Salimon, C. and Cunha, H. | Factors controlling water-column respiration in rivers of the central and southwestern Amazon Basin [BibTeX] |
2012 | Limnology and Oceanography Vol. 57(2), pp. 527-540 |
article | DOI |
BibTeX:
@article{ellis_factors_2012, author = {Ellis, E.E. and Richey, J.E. and Aufdenkampe, A.K. and Krusche, A.V. and Quay, P.D. and Salimon, C. and Cunha, H.B.da}, title = {Factors controlling water-column respiration in rivers of the central and southwestern Amazon Basin}, journal = {Limnology and Oceanography}, year = {2012}, volume = {57}, number = {2}, pages = {527--540}, doi = {https://doi.org/10.4319/lo.2012.57.2.0527} } |
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Eller, C.B., Rowland, L., Oliveira, R.S., Bittencourt, P.R.L., Barros, F.V., da Costa, A.C.L., Meir, P., Friend, A.D., Mencuccini, M., Sitch, S. and Cox, P. | Modelling tropical forest responses to drought and El Niño with a stomatal optimization model based on xylem hydraulics [BibTeX] |
2018 | Philosophical Transactions of The Royal Society B-Biological Sciences Vol. 373, pp. 20170315 |
article | |
BibTeX:
@article{eller_modelling_2018, author = {Eller, Cleiton B. and Rowland, Lucy and Oliveira, Rafael S. and Bittencourt, Paulo R. L. and Barros, Fernanda V. and da Costa, Antonio C. L. and Meir, Patrick and Friend, Andrew D. and Mencuccini, Maurizio and Sitch, Stephen and Cox, Peter}, title = {Modelling tropical forest responses to drought and El Niño with a stomatal optimization model based on xylem hydraulics}, journal = {Philosophical Transactions of The Royal Society B-Biological Sciences}, year = {2018}, volume = {373}, pages = {20170315} } |
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Elias, F., Ferreira, J., Resende, A.F., Berenguer, E., França, F., Smith, C.C., Schwartz, G., Nascimento, R.O., Guedes, M., Chesini Rossi, L., Maria Moraes de Seixas, M., Melo da Silva, C. and Barlow, J. | Comparing contemporary and lifetime rates of carbon accumulation from secondary forests in the eastern Amazon | 2022 | Forest Ecology and Management Vol. 508, pp. 120053 |
article | DOI URL |
Abstract: Secondary forests (SFs) growing on previously cleared land could be a low-cost climate change mitigation strategy due to their potential to sequester CO2. However, given widespread changes in climate and land-use in the Amazon in the past 20 years, it is not clear whether current rates of carbon uptake by SFs reflect estimates based on dividing the carbon stock by the estimated age of the forest. This is important, as differences between methodological approaches could lead to important discrepancies in estimates of carbon accumulation. Furthermore, we know little about how carbon uptake rates of secondary forests vary across some of the most deforested regions of the Amazon, where reforestation actions are most needed. Here, we compare the rates of carbon accumulation estimated over the lifetime of a stand (by stand age) with the contemporary rates estimated by recensus data, based on 28 permanent SFs plots distributed across four regions. Then, we compare how carbon uptakes rates vary across regions and how they compare to previous studies. The average rates of contemporary (1.23 ± 0.57 Mg C ha−1 yr−1) and lifetime (1.14 ± 0.63 Mg C ha−1 yr−1) carbon accumulation were strongly correlated (r = 0.78) and similar between regions. Overall, our carbon accumulation rates were much lower than other estimates of Amazonian SFs, which suggests that regions with the greatest opportunities for large-scale implementation of SFs have some of the slowest rates of carbon accumulation. Contrary to predictions from chronosequence analysis, the lack of difference between lifetime and contemporary rates of carbon accumulation suggests forests are maintaining a consistent rate of growth in the first decades after abandonment. These results—combined with the high rates of ongoing environmental change - highlight the importance of continuing to monitor the rate of carbon accumulation in secondary forests. This is necessary to support the implementation and monitoring of large-scale passive restoration in the highly-deforested Amazon. | |||||
BibTeX:
@article{elias_comparing_2022, author = {Elias, Fernando and Ferreira, Joice and Resende, Angélica F. and Berenguer, Erika and França, Filipe and Smith, Charlotte C. and Schwartz, Gustavo and Nascimento, Rodrigo O. and Guedes, Matheus and Chesini Rossi, Liana and Maria Moraes de Seixas, Marina and Melo da Silva, Carolina and Barlow, Jos}, title = {Comparing contemporary and lifetime rates of carbon accumulation from secondary forests in the eastern Amazon}, journal = {Forest Ecology and Management}, year = {2022}, volume = {508}, pages = {120053}, url = {https://www.sciencedirect.com/science/article/pii/S0378112722000470}, doi = {https://doi.org/10.1016/j.foreco.2022.120053} } |
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Elbaz-Poulichet, F., Seyler, P., Maurice-Bourgoin, L., Guyot, J.L. and Dupuy, C. | Trace element geochemistry in the upper Amazon drainage basin (Bolivia) | 1999 | Chemical Geology Vol. 157(3-4), pp. 319-334 |
article | DOI URL |
Abstract: The distribution of trace elements (Sr, Mo, Ba, Rb, U, Mn, Ni, Cu, Zn, and Cd) was investigated in surface waters and associated particulates in two upper Amazonian basins (Mamore and Beni). Dissolved Sr, Ba, Mo, Rb, U and to a lesser extent Zn and Cd correlate with major ions and appear to be predominantly derived from soluble rocks (carbonates, evaporites or sulfides essentially contained in shales). These elements are conservative in waters except in highly alkaline or sulfate-rich waters where calcite and barite can precipitate. The concentrations of transition element are generally not correlated with major ion chemistry. Their behaviour can be largely explained by equilibrium reactions in solution and solid-liquid exchanges. Additionally, the distribution of Mn and Cu reflects also the lithological differences between the Mamore and Beni basins, The occurrence of mineralisation in the Beni basin explains the high Zn, Cd as well as the concentrations of Cu in some rivers of the Beni basin. The higher content of Mn in the Mamore basin may reflects the predominance of carbonate rocks. The fractionation of trace elements in SPM has been attributed to the sorting of feldspars during transport in water, and to the mixing between clay minerals and quartz. These minerals, refractory to weathering and introduced in water rivers by mechanical erosion, have not contributed to the dissolved load. (C) 1999 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{elbaz-poulichet_trace_1999, author = {Elbaz-Poulichet, F. and Seyler, P. and Maurice-Bourgoin, L. and Guyot, J. L. and Dupuy, C.}, title = {Trace element geochemistry in the upper Amazon drainage basin (Bolivia)}, journal = {Chemical Geology}, year = {1999}, volume = {157}, number = {3-4}, pages = {319--334}, url = {://WOS:000079987200010}, doi = {https://doi.org/10.1016/s0009-2541(99)00015-7} } |
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Ekstrom, S., Noziere, B., Hultberg, M., Alsberg, T., Magner, J., Nilsson, E.D. and Artaxo, P. | A possible role of ground-based microorganisms on cloud formation in the atmosphere | 2010 | Biogeosciences Vol. 7(1), pp. 387-394 |
article | URL |
Abstract: The formation of clouds is an important process for the atmosphere, the hydrological cycle, and climate, but some aspects of it are not completely understood. In this work, we show that microorganisms might affect cloud formation without leaving the Earth's surface by releasing biological surfactants (or biosurfactants) in the environment, that make their way into atmospheric aerosols and could significantly enhance their activation into cloud droplets. In the first part of this work, the cloud-nucleating efficiency of standard biosurfactants was characterized and found to be better than that of any aerosol material studied so far, including inorganic salts. These results identify molecular structures that give organic compounds exceptional cloud-nucleating properties. In the second part, atmospheric aerosols were sampled at different locations: a temperate coastal site, a marine site, a temperate forest, and a tropical forest. Their surface tension was measured and found to be below 30 mN/m, the lowest reported for aerosols, to our knowledge. This very low surface tension was attributed to the presence of biosurfactants, the only natural substances able to reach to such low values. The presence of strong microbial surfactants in aerosols would be consistent with the organic fractions of exceptional cloud-nucleating efficiency recently found in aerosols, and with the correlations between algae bloom and cloud cover reported in the Southern Ocean. The results of this work also suggest that biosurfactants might be common in aerosols and thus of global relevance. If this is confirmed, a new role for microorganisms on the atmosphere and climate could be identified. | |||||
BibTeX:
@article{ekstrom_possible_2010, author = {Ekstrom, S. and Noziere, B. and Hultberg, M. and Alsberg, T. and Magner, J. and Nilsson, E. D. and Artaxo, P.}, title = {A possible role of ground-based microorganisms on cloud formation in the atmosphere}, journal = {Biogeosciences}, year = {2010}, volume = {7}, number = {1}, pages = {387--394}, url = {://WOS:000274058100030} } |
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Ekman, A.M.L., Krejci, R., Engstrom, A., Strom, J., de Reus, M., Williams, J. and Andreae, M.O. | Do organics contribute to small particle formation in the Amazonian upper troposphere? | 2008 | Geophysical Research Letters Vol. 35(17) |
article | DOI URL |
Abstract: 3-D cloud-resolving model simulations including explicit aerosol physics and chemistry are compared with observations of upper tropospheric (12 km) aerosol size distributions over the Amazon Basin. The model underestimates the aerosol number concentration for all modes, especially the nucleation mode (d textless 18 nm). We show that a boundary layer SO(2) mixing ratio of approximately 5 ppb would be needed in order to reproduce the high nucleation mode number concentrations observed. This high SO(2) mixing ratio is very unlikely for the pristine Amazon Basin at this time of the year. Hence, it is suggested that vapours other than H(2)SO(4) participate in the formation and growth of small aerosols. Using activation nucleation theory together with a small (0.4-10%) secondary organic aerosol mass yield, we show that isoprene has the potential of substantially increasing the number of small particles formed as well as reducing the underestimate for the larger aerosol modes. | |||||
BibTeX:
@article{ekman_organics_2008, author = {Ekman, A. M. L. and Krejci, R. and Engstrom, Anders and Strom, Johan and de Reus, Marian and Williams, Jonathan and Andreae, Meinrat O.}, title = {Do organics contribute to small particle formation in the Amazonian upper troposphere?}, journal = {Geophysical Research Letters}, year = {2008}, volume = {35}, number = {17}, url = {://WOS:000259199500003}, doi = {https://doi.org/10.1029/2008gl034970} } |
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Eitel, J., Höfle, B., Vierling, L., Abéllan, A., Asner, G., Deems, J., Glennie, C., Joerg, P., LeWinter, A., Magney, T., Mandlburger, G., Morton, D., Müller, J. and Vierling, K. | Beyond 3-D: the new spectrum of lidar applications for Earth and Ecological science [BibTeX] |
2016 | Remote Sensing of Environment Vol. 186, pp. 372-392 |
article | DOI |
BibTeX:
@article{eitel_beyond_2016, author = {Eitel, JUH. and Höfle, B. and Vierling, LA. and Abéllan, A. and Asner, GP. and Deems, JS. and Glennie, C. and Joerg, PC. and LeWinter, A. and Magney, TS. and Mandlburger, G. and Morton, DC. and Müller, J. and Vierling, K.}, title = {Beyond 3-D: the new spectrum of lidar applications for Earth and Ecological science}, journal = {Remote Sensing of Environment}, year = {2016}, volume = {186}, pages = {372--392}, doi = {https://doi.org/10.1016/j.rse.2016.08.018} } |
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Ehleringer, J.R., Bowling, D.R., Flanagan, L.B., Fessenden, J., Helliker, B., Martinelli, L.A. and Ometto, J.P. | Stable isotopes and carbon cycle processes in forests and grasslands | 2002 | Plant Biology Vol. 4(2), pp. 181-189 |
article | DOI URL |
Abstract: Scaling and partitioning are frequently two difficult challenges facing ecology today. With regard to ecosystem carbon balance studies, ecologists and atmospheric scientists are often interested in asking how fluxes of carbon dioxide scale across the landscape, region and continent. Yet at the same time, physiological ecologists and ecosystem ecologists are interested in dissecting the net ecosystem CO2 exchange between the biosphere and the atmosphere to achieve a better understanding of the balance between photosynthesis and respiration within a forest. in both of these multiple-scale ecological questions, stable isotope analyses of carbon dioxide can play a central role in influencing our understanding of the extent to which terrestrial ecosystems are carbon sinks. In this synthesis, we review the theory and present field evidence to address isotopic scaling of CO2 fluxes. We first show that the C-13 isotopic signal which ecosystems impart to the atmosphere does not remain constant over time at either temporal or spatial scales. The relative balances of different biological activities and plant responses to stress result in dynamic changes in the C-13 isotopic exchange between the biosphere and atmosphere, with both seasonal and stand-age factors playing major roles influencing the C-13 biosphere-atmosphere exchange. We then examine how stable isotopes are used to partition net ecosystem exchange fluxes in order to calculate shifts in the balance of photosynthesis and respiration. Lastly, we explore how fundamental differences in the O-18 isotopic gas exchange of forest and grassland ecosystems can be used to further partition terrestrial fluxes. | |||||
BibTeX:
@article{ehleringer_stable_2002, author = {Ehleringer, J. R. and Bowling, D. R. and Flanagan, L. B. and Fessenden, J. and Helliker, B. and Martinelli, L. A. and Ometto, J. P.}, title = {Stable isotopes and carbon cycle processes in forests and grasslands}, journal = {Plant Biology}, year = {2002}, volume = {4}, number = {2}, pages = {181--189}, url = {://WOS:000175207700007}, doi = {https://doi.org/10.1055/s-2002-25733} } |
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Efraim, A., Lauer, O., Rosenfeld, D., Braga, R.C., Franco, M.A., Kremper, L.A., Zhu, Y., Pöschl, U., Pöhlker, C., Andreae, M.O., Artaxo, P., de Araújo, A.C. and Pöhlker, M.L. | Satellite-Based Detection of Secondary Droplet Activation in Convective Clouds | 2022 | Journal of Geophysical Research: Atmospheres Vol. 127(12), pp. e2022JD036519 |
article | DOI URL |
Abstract: Abstract We present a new approach of analyzing and interpreting vertical profiles of cloud microstructure obtained by satellite remote sensing. The method is based on a spectral bin microphysics adiabatic parcel model and aims to elucidate the effects of aerosols on the evolution of convective clouds and related microphysical processes, including the activation of cloud condensation nuclei (CCN), the growth of cloud droplets, and the formation of precipitation. Characteristic features in the vertical profiles of effective radius (re) and temperature (T) reveal different microphysical zones in convective clouds related to the change increase of re with decreasing T. The classification of the different microphysical zones includes the (a) condensational growth of droplets, (b) growth by coalescence, (c) rainout, (d) secondary droplet activation zone (SAZ), (e) mixed-phase of ice particles and water droplets, and (f) glaciation of the cloud. The detection of the SAZ is introduced here for the first time. This method allows us to identify the activation of aerosol particles above cloud base and their role in the invigoration of deep convective clouds. | |||||
BibTeX:
@article{efraim_satellite-based_2022, author = {Efraim, Avichay and Lauer, Oliver and Rosenfeld, Daniel and Braga, Ramon C. and Franco, Marco A. and Kremper, Leslie A. and Zhu, Yannian and Pöschl, Ulrich and Pöhlker, Christopher and Andreae, Meinrat O. and Artaxo, Paulo and de Araújo, Alessandro C. and Pöhlker, Mira L.}, title = {Satellite-Based Detection of Secondary Droplet Activation in Convective Clouds}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2022}, volume = {127}, number = {12}, pages = {e2022JD036519}, url = {https://doi.org/10.1029/2022JD036519}, doi = {https://doi.org/10.1029/2022JD036519} } |
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Edtbauer, A., Pfannerstill, E.Y., Pires Florentino, A.P., Barbosa, C.G.G., Rodriguez-Caballero, E., Zannoni, N., Alves, R.P., Wolff, S., Tsokankunku, A., Aptroot, A., de Oliveira Sá, M., de Araújo, A.C., Sörgel, M., de Oliveira, S.M., Weber, B. and Williams, J. | Cryptogamic organisms are a substantial source and sink for volatile organic compounds in the Amazon region | 2021 | Communications Earth & Environment Vol. 2(1), pp. 258 |
article | DOI URL |
Abstract: Cryptogamic organisms such as bryophytes and lichens cover most surfaces within tropical forests, yet their impact on the emission of biogenic volatile organic compounds is unknown. These compounds can strongly influence atmospheric oxidant levels as well as secondary organic aerosol concentrations, and forest canopy leaves have been considered the dominant source of these emissions. Here we present cuvette flux measurements, made in the Amazon rainforest between 2016–2018, and show that common bryophytes emit large quantities of highly reactive sesquiterpenoids and that widespread lichens strongly uptake atmospheric oxidation products. A spatial upscaling approach revealed that cryptogamic organisms emit sesquiterpenoids in quantities comparable to current canopy attributed estimates, and take up atmospheric oxidation products at rates comparable to hydroxyl radical chemistry. We conclude that cryptogamic organisms play an important and hitherto overlooked role in atmospheric chemistry above and within tropical rainforests. | |||||
BibTeX:
@article{edtbauer_cryptogamic_2021, author = {Edtbauer, Achim and Pfannerstill, Eva Y. and Pires Florentino, Ana Paula and Barbosa, Cybelli G. G. and Rodriguez-Caballero, Emilio and Zannoni, Nora and Alves, Rodrigo P. and Wolff, Stefan and Tsokankunku, Anywhere and Aptroot, André and de Oliveira Sá, Marta and de Araújo, Alessandro C. and Sörgel, Matthias and de Oliveira, Sylvia Mota and Weber, Bettina and Williams, Jonathan}, title = {Cryptogamic organisms are a substantial source and sink for volatile organic compounds in the Amazon region}, journal = {Communications Earth & Environment}, year = {2021}, volume = {2}, number = {1}, pages = {258}, url = {https://doi.org/10.1038/s43247-021-00328-y}, doi = {https://doi.org/10.1038/s43247-021-00328-y} } |
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Eck, T.F., Holben, B.N., Reid, J.S., O'Neill, N.T., Schafer, J.S., Dubovik, O., Smirnov, A., Yamasoe, M.A. and Artaxo, P. | High aerosol optical depth biomass burning events: A comparison of optical properties for different source regions | 2003 | Geophysical Research Letters Vol. 30(20) |
article | DOI URL |
Abstract: [1] The optical properties of aerosols such as smoke from biomass burning vary due to aging processes and these particles reach larger sizes at high concentrations. We compare the spectra of aerosol optical depth (tau(a)), column-integrated volume size distributions, refractive indices, and single scattering albedo retrieved from AERONET observations for four selected events of very high smoke optical depth (tau(a) similar to 2 at 500 nm). Two case studies are from tropical biomass burning regions ( Brazil and Zambia) and two are cases of boreal forest and peat fire smoke transported long distances to sites in the US and Moldova. Smoke properties for these extreme events can be significantly different from those reported in more typical plumes. In particular, large differences in smoke fine mode particle radius ( similar to 0.17 to 0.25 mum) and single scattering albedo ( similar to 0.88 to 0.99 at 440 nm) were observed as a result of differences in fuels burned, combustion phase, and aging. | |||||
BibTeX:
@article{eck_high_2003, author = {Eck, T. F. and Holben, B. N. and Reid, J. S. and O'Neill, N. T. and Schafer, J. S. and Dubovik, O. and Smirnov, A. and Yamasoe, M. A. and Artaxo, P.}, title = {High aerosol optical depth biomass burning events: A comparison of optical properties for different source regions}, journal = {Geophysical Research Letters}, year = {2003}, volume = {30}, number = {20}, url = {://WOS:000186197900002}, doi = {https://doi.org/10.1029/2003gl017861} } |
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Eck, T.F., Holben, B.N., Reid, J.S., Giles, D.M., Rivas, M.A., Singh, R.P., Tripathi, S.N., Bruegge, C.J., Platnick, S., Arnold, G.T., Krotkov, N.A., Carn, S.A., Sinyuk, A., Dubovik, O., Arola, A., Schafer, J.S., Artaxo, P., Smirnov, A., Chen, H. and Goloub, P. | Fog and Cloud Induced Aerosol Modification Observed by AERONET [BibTeX] |
2012 | Journal of Geophysical Research Vol. 117, pp. D07206 |
article | |
BibTeX:
@article{eck_fog_2012, author = {Eck, T. F. and Holben, B. N. and Reid, J. S. and Giles, D. M. and Rivas, M. A. and Singh, R. P. and Tripathi, S. N. and Bruegge, C. J. and Platnick, S. and Arnold, G. T. and Krotkov, N. A. and Carn, S. A. and Sinyuk, A. and Dubovik, O. and Arola, A. and Schafer, J. S. and Artaxo, P. and Smirnov, A. and Chen, H. and Goloub, P.}, title = {Fog and Cloud Induced Aerosol Modification Observed by AERONET}, journal = {Journal of Geophysical Research}, year = {2012}, volume = {117}, pages = {D07206} } |
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Echalar, F., Artaxo, P., Martins, J.V., Yamasoe, M., Gerab, F., Maenhaut, W. and Holben, B. | Long-term monitoring of atmospheric aerosols in the Amazon Basin: Source identification and apportionment | 1998 | Journal of Geophysical Research-Atmospheres Vol. 103(D24), pp. 31849-31864 |
article | DOI URL |
Abstract: Continuous sampling of atmospheric aerosols was carried out at mio different sites in the Amazon Basin: Cuiaba (16 degrees S, 56 degrees W), since July 1990, and Alta Floresta (09 degrees S, 56 degrees W), since August 1992. Aerosols were collected on polycarbonate filters mounted in stacked filter units (SFU). Particle-induced X ray emission (PIXE) was used to measure concentrations of up to 26 elements (Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Zr, Au, and Pb). Black carbon (BC) and gravimetric mass analyses were also performed. Inhalable particle ground concentrations showed a marked seasonality, with maxima of more than 100 mu g m(-3) in the dry season. The high aerosol optical thickness (AOT) values in this period (up to 4.0 at lambda = 0.440 mu m) indicate that the whole air column has a significant aerosol load. Three main types of aerosol sources were identified: biomass burning, natural biogenic emissions, and soil dust resuspension. During the dry season the fine mode aerosol originated predominantly from biomass burning emissions (they were responsible for about 73% of fine aerosol mass), while the coarse mode was dominated by soil dust particles (50 to 60% of the aerosol mass). Crustal elements exhibited a unimodal coarse mode size distribution, while the pyrogenic elements showed a clear submicrometer mode. Black carbon had a submicrometer mode centered at 0.175 mu m. During the wet season, biogenic aerosols were the dominant particle type and also the main source of atmospheric P in the region. | |||||
BibTeX:
@article{echalar_long-term_1998, author = {Echalar, F. and Artaxo, P. and Martins, J. V. and Yamasoe, M. and Gerab, F. and Maenhaut, W. and Holben, B.}, title = {Long-term monitoring of atmospheric aerosols in the Amazon Basin: Source identification and apportionment}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1998}, volume = {103}, number = {D24}, pages = {31849--31864}, url = {://WOS:000077967000025}, doi = {https://doi.org/10.1029/98jd01749} } |
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Ebben, C.J., Zorn, S.R., Lee, S.-B., Artaxo, P., Martin, S.T. and Geiger, F.M. | Stereochemical transfer to atmospheric aerosol particles accompanying the oxidation of biogenic volatile organic compounds | 2011 | Geophysical Research Letters Vol. 38 |
article | DOI URL |
Abstract: Asymmetric emission profiles of the stereoisomers of plant-derived volatile organic compounds vary with season, geography, plant type, and stress factors. After oxidation of these compounds in the atmosphere, the low-vapor pressure products ultimately contribute strongly to the particle-phase material of the atmosphere. In order to explore the possibility of stereochemical transfer to atmospheric aerosol particles during the oxidation of biogenic volatile organic compounds, second-order coherent vibrational spectra were recorded of the particle-phase organic material produced by the oxidation of different stereoisomeric mixes of alpha-pinene. The spectra show that the stereochemical configurations are not scrambled but instead are transferred from the gas-phase molecular precursors to the particle-phase molecules. The spectra also show that oligomers formed in the particle phase have a handed superstructure that depends strongly and nonlinearly on the initial stereochemical composition of the precursors. Because the stereochemical mix of the precursors for a material can influence the physical and chemical properties of that material, our findings suggest that chirality is also important for such properties of plant-derived aerosol particles. Citation: Ebben, C. J., S. R. Zorn, S.-B. Lee, P. Artaxo, S. T. Martin, and F. M. Geiger (2011), Stereochemical transfer to atmospheric aerosol particles accompanying the oxidation of biogenic volatile organic compounds, Geophys. Res. Lett., 38, L16807, doi: 10.1029/2011GL048599. | |||||
BibTeX:
@article{ebben_stereochemical_2011, author = {Ebben, Carlena J. and Zorn, Soeren R. and Lee, Seung-Bok and Artaxo, Paulo and Martin, Scot T. and Geiger, Franz M.}, title = {Stereochemical transfer to atmospheric aerosol particles accompanying the oxidation of biogenic volatile organic compounds}, journal = {Geophysical Research Letters}, year = {2011}, volume = {38}, url = {://WOS:000294368300006}, doi = {https://doi.org/10.1029/2011gl048599} } |
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Ebben, C.J., Martinez, I.S., Shrestha, M., Buchbinder, A.M., Corrigan, A.L., Guenther, A., Karl, T., Petaja, T., Song, W., Zorn, S.R., Artaxo, P., Kulmala, M., Martin, S.T., Russell, L.M., Williams, J. and Geiger, F.M. | Contrasting organic aerosol particles from boreal and tropical forests during HUMPPA-COPEC-2010 and AMAZE-08 using coherent vibrational spectroscopy [BibTeX] |
2011 | Atmospheric Chemistry and Physics Vol. 11, pp. 10327-10329 |
article | DOI |
BibTeX:
@article{ebben_contrasting_2011, author = {Ebben, C. J. and Martinez, I. S. and Shrestha, M. and Buchbinder, A. M. and Corrigan, A. L. and Guenther, A. and Karl, T. and Petaja, T. and Song, W.W. and Zorn, S. R. and Artaxo, P. and Kulmala, M. and Martin, S. T. and Russell, L. M. and Williams, J. and Geiger, F. M.}, title = {Contrasting organic aerosol particles from boreal and tropical forests during HUMPPA-COPEC-2010 and AMAZE-08 using coherent vibrational spectroscopy}, journal = {Atmospheric Chemistry and Physics}, year = {2011}, volume = {11}, pages = {10327--10329}, doi = {https://doi.org/10.5194/acp-11-10317-2011} } |
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Ebben Mona Shrestha, I.S.M.A.L.C.A.A.F.W.W.S.D.R.W.T.P.J.W.L.M.R.M.K.A.H.G.P.A.S.T.M.R.J.T.and.F.M.G.C.J. | Secondary Organic Aerosol Particles from Southern Finland, Amazonia, and California Studied by Coherent Vibrational Spectroscopy [BibTeX] |
2012 | Journal of Physical Chemistry A Feature Article Vol. 116, pp. 8271-8290 |
article | DOI |
BibTeX:
@article{ebben_secondary_2012, author = {Ebben, Mona Shrestha, Imee S. Martinez, Ashley L. Corrigan, Amanda A. Frossard, Wei W. Song, David R. Worton, Tuukka Petäjä, Jonathan Williams, Lynn M. Russell, Markku Kulmala, Allen H. Goldstein, Paulo Artaxo, Scot T. Martin, Regan J. Thomson, and Franz M. Geiger., Carlena J.}, title = {Secondary Organic Aerosol Particles from Southern Finland, Amazonia, and California Studied by Coherent Vibrational Spectroscopy}, journal = {Journal of Physical Chemistry A Feature Article}, year = {2012}, volume = {116}, pages = {8271--8290}, doi = {https://doi.org/10.1021/jp302631z} } |
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Durieux, L., Machado, L.A.T. and Laurent, H. | The impact of deforestation on cloud cover over the Amazon arc of deforestation | 2003 | Remote Sensing of Environment Vol. 86(1), pp. 132-140 |
article | DOI URL |
Abstract: Atmospheric general circulation model (AGCM) simulations predict that a complete deforestation of the Amazon basin would lead to a significant climate change; however, it is more difficult to determine the amount of deforestation that would lead to a detectable climate change. This paper examines whether cloudiness has already changed locally in the Brazilian arc of deforestation, one of the most deforested regions of the Amazon basin, where over 15% of the primary forest has been converted to pasture and agriculture. Three pairs of deforested/forested areas have been selected at a scale compatible with that of climate model grids to compare changes in land cover with changes in cloudiness observed in satellite data over a 10-year period from 1984 to 1993. Analysis of cloud cover trends suggests that a regional climate change may already be underway in the most deforested part of the arc of deforestation. Although changes in cloud cover over deforested areas are not significant for interannual variations, they are for the seasonal and diurnal distributions. During the dry season, observations show more low-level clouds in early afternoon and less convection at night and in early morning over deforested areas. During the wet season, convective cloudiness is enhanced in the early night over deforested areas. Generally speaking, the results suggest that deforestation may lead to increased seasonality; however, some of the differences observed between deforested and forested areas may be related to their different geographical locations. (C) 2003 Elsevier Science Inc. All rights reserved. | |||||
BibTeX:
@article{durieux_impact_2003, author = {Durieux, L. and Machado, L. A. T. and Laurent, H.}, title = {The impact of deforestation on cloud cover over the Amazon arc of deforestation}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {86}, number = {1}, pages = {132--140}, url = {://WOS:000183932300010}, doi = {https://doi.org/10.1016/s0034-4257(03)00095-6} } |
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Durgante, F.M., Higuchi, N., Ohashi, S., Householder, J.E., Lima, A.J.N., Ishizuka, M., Wittmann, F., dos Santos, J., Carneiro, V.M.C., Xu, X., do Nascimento, C.C., Schöngart, J., Piedade, M.T.F., Schmitt, A.R.K., Alves, Y.L.A., Lehman, J., Gimenez, B.O., Baggio, P.M., de Ourique, L.K. and Trumbore, S. | Soil fertility and drought interact to determine large variations in wood production for a hyperdominant Amazonian tree species | 2023 | Frontiers in Forests and Global Change Vol. 5 |
article | DOI URL |
Abstract: textlesssectextgreaterIntroductionThe productivity of the Amazon Rainforest is related to climate and soil fertility. However, the degrees to which these interactions influence multiannual to decadal variations in tree diameter growth are still poorly explored.textless/sectextgreatertextlesssectextgreaterMethodsTo fill this gap, we used radiocarbon measurements to evaluate the variation in tree growth rates over the past decades in an important hyperdominant species, Eschweilera coriacea (Lecythidaceae), from six sites in the Brazilian Amazon that span a range of soil properties and climate.textless/sectextgreatertextlesssectextgreaterResultsUsing linear mixed-effects models, we show that temporal variations in mean annual diameter increment evaluated over a specific time period reflect interactions between soil fertility and the drought index (SPEI-Standardized Precipitation and Evapotranspiration Index).textless/sectextgreatertextlesssectextgreaterDiscussionOur results indicate that the growth response of trees to drought is strongly dependent on soil conditions, a facet of forest productivity that is still underexplored, and which has great potential for improving predictions of future tropical tree growth in the face of projected climate change.textless/sectextgreater | |||||
BibTeX:
@article{durgante_soil_2023, author = {Durgante, Flavia Machado and Higuchi, Niro and Ohashi, Shinta and Householder, John Ethan and Lima, Adriano José Nogueira and Ishizuka, Moriyoshi and Wittmann, Florian and dos Santos, Joaquim and Carneiro, Vilany Matilla Colares and Xu, Xiaomei and do Nascimento, Claudete Catanhede and Schöngart, Jochen and Piedade, Maria Teresa Fernandez and Schmitt, Adalberto Rodrigo Kossmann and Alves, Yanka Laryssa Almeida and Lehman, Jennifer and Gimenez, Bruno Oliva and Baggio, Priscilla Maia and de Ourique, Lucas Kosvoski and Trumbore, Susan}, title = {Soil fertility and drought interact to determine large variations in wood production for a hyperdominant Amazonian tree species}, journal = {Frontiers in Forests and Global Change}, year = {2023}, volume = {5}, url = {https://www.frontiersin.org/articles/10.3389/ffgc.2022.1065645}, doi = {https://doi.org/10.3389/ffgc.2022.1065645} } |
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Dunne, J.A., Saleska, S.R., Fischer, M.L. and Harte, J. | Integrating experimental and gradient methods in ecological climate change research | 2004 | Ecology Vol. 85(4), pp. 904-916 |
article | DOI URL |
Abstract: Field-based research on the responses of ecosystems to anthropogenic climate change has primarily used either natural gradient or experimental methods. Taken separately, each approach faces methodological, spatial, and temporal limitations that potentially constrain the generality of results and predictions. Integration of the two approaches within a single study can overcome some of those limitations and provide ways to distinguish among consistent, dynamic, and context-dependent ecosystem responses to global warming. A simple conceptual model and two case studies that focus on climate change impacts on flowering phenology and carbon cycling in a subalpine meadow ecosystem illustrate the utility of this type of integration. | |||||
BibTeX:
@article{dunne_integrating_2004, author = {Dunne, J. A. and Saleska, S. R. and Fischer, M. L. and Harte, J.}, title = {Integrating experimental and gradient methods in ecological climate change research}, journal = {Ecology}, year = {2004}, volume = {85}, number = {4}, pages = {904--916}, url = {://WOS:000220766600002}, doi = {https://doi.org/10.1890/03-8003} } |
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Duarte, F. | Variabilidade e tendência das chuvas em Rio Branco, Acre, Brasil. [BibTeX] |
2005 | Revista Brasileira de Meteorologia Vol. 20, pp. 37-42 |
article | |
BibTeX:
@article{duarte_variabilidade_2005, author = {Duarte, F.A.}, title = {Variabilidade e tendência das chuvas em Rio Branco, Acre, Brasil.}, journal = {Revista Brasileira de Meteorologia}, year = {2005}, volume = {20}, pages = {37--42} } |
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Duarte, A. | Aspectos da climatologia do Acre, Brasil, com base no intervalo 1971 - 2000 [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 308-317 |
article | |
BibTeX:
@article{duarte_aspectos_2006, author = {Duarte, A.F.}, title = {Aspectos da climatologia do Acre, Brasil, com base no intervalo 1971 - 2000}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {308--317} } |
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Doughty, D.B., Girardin, C.A.J., Amézquita, F.F., Cabrera, D.G., Huasco, W.H., Silva-Espejo, J.E., Araujo-Murakami, A., da Costa, M.C., Rocha, W., Feldpausch, T.R., Mendoza, A.L.M., da Costa, A.C.L., Meir, P., Phillips, O.L., Malhi Y., C.E. and Metcalfe | Drought impact on forest carbon dynamics and fluxes in Amazonia. [BibTeX] |
2015 | Nature Vol. 519, pp. 78-82 |
article | |
BibTeX:
@article{doughty_drought_2015, author = {Doughty, D. B. ; Girardin, C. A. J. ; Amézquita, F. Farfán ; Cabrera, D. Galiano ; Huasco, W. Huaraca ; Silva-Espejo, J. E. ; Araujo-Murakami, A. ; da Costa, M. C. ; Rocha, W. ; Feldpausch, T. R. ; Mendoza, A. L. M. ; da Costa, A. C. L. ; Meir, P. ; Phillips, O. L. ; Malhi, Y., Christopher E. ; Metcalfe}, title = {Drought impact on forest carbon dynamics and fluxes in Amazonia.}, journal = {Nature}, year = {2015}, volume = {519}, pages = {78--82} } |
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Doughty, C.E., Metcalfe, D.B., Costa, M.C.d., Oliveira, A.A.d., Neto, G., Silva, J.A., Aragão, L.E., Almeida, S.S., Quesada, C.A., Cecile A.J. Girardin, Kate Halladay, Anthony C.L. da Costa and Yadvinder Malhi | The production, allocation and cycling of carbon in a forest on fertile terra preta soil in eastern Amazonia compared with a forest on adjacent infertile soil [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 41-53 |
article | |
BibTeX:
@article{doughty_production_2014, author = {Doughty, Christopher E. and Metcalfe, Daniel B. and Costa, Mauricio C. da and Oliveira, Alex A.R. de and Neto, G.F.C. and Silva, João A. and Aragão, Luiz E.O.C. and Almeida, Samuel S. and Quesada, Carlos A. and Cecile A.J. Girardin and Kate Halladay and Anthony C.L. da Costa and Yadvinder Malhi}, title = {The production, allocation and cycling of carbon in a forest on fertile terra preta soil in eastern Amazonia compared with a forest on adjacent infertile soil}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {41--53} } |
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Doughty, C.E., Goulden, M.L., Miller, S.D. and da Rocha, H.R. | Circadian rhythms constrain leaf and canopy gas exchange in an Amazonian forest | 2006 | Geophysical Research Letters Vol. 33(15) |
article | DOI URL |
Abstract: We used a controlled-environment leaf gas-exchange system and the micrometeorological technique eddy covariance to determine whether circadian rhythms constrain the rates of leaf and canopy gas exchange in an Amazonian forest over a day. When exposed to continuous and constant light for 20 to 48 hours leaves of eleven of seventeen species reduced their photosynthetic rates and closed their stomata during the normally dark period and resumed active gas exchange during the normally light period. Similarly, the rate of whole-forest CO2 uptake at a predetermined irradiance declined during the late afternoon and early morning and increased during the middle of the day. We attribute these cycles to circadian rhythms that are analogous to ones that have been reported for herbaceous plants in the laboratory. The importance of endogenous gas exchange rhythms presents a previously unrecognized challenge for efforts to both interpret and model land-atmosphere energy and mass exchange. | |||||
BibTeX:
@article{doughty_circadian_2006, author = {Doughty, Christopher E. and Goulden, Michael L. and Miller, Scott D. and da Rocha, Humberto R.}, title = {Circadian rhythms constrain leaf and canopy gas exchange in an Amazonian forest}, journal = {Geophysical Research Letters}, year = {2006}, volume = {33}, number = {15}, url = {://WOS:000239785800007 http://www.agu.org/pubs/crossref/2006/2006GL026750.shtml}, doi = {https://doi.org/10.1029/2006gl026750} } |
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Doughty, C.E. and Goulden, M.L. | Are tropical forests near a high temperature threshold? | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: We used leaf gas exchange, sap flow, and eddy covariance measurements to investigate whether high temperature substantially limits CO(2) uptake at the LBA-ECO (Large-scale Biosphere-Atmosphere) km-83 tropical forest site in Brazil. Leaf-level temperature-photosynthesis curves, and comparisons of whole-canopy net ecosystem CO2 exchange (NEE) with air temperature, showed that CO(2) uptake declined sharply during warm periods. Observations of ambient leaf microclimate showed that leaves oscillate between two states: a cool, dimly lit stage and a hot, brightly illuminated stage where leaf temperatures are often greater than 35 degrees C. The leaf-level rates of photosynthesis decreased when shaded leaves (similar to ambient air temperature and textless 500 mu mmol m(-2) s(-1)) were transferred into a prewarmed, brightly illuminated chamber (35 degrees to 38 degrees C and 1000 mmol m(-2) s(-1)), coincident with increased leaf temperature, increased evaporative demand, and stomatal closure. The rates of whole-canopy CO(2) uptake calculated at 5-min intervals increased initially at the onset of sunny periods that followed extended cloudy periods, but then decreased as the sunlight continued, leaf temperature and evaporative demand increased, and canopy conductance decreased. The forest at km-83 appears to be close to a high temperature threshold, above which CO(2) uptake drops sharply. This sensitivity results in part from the covariance between leaf temperature and leaf illumination; the brightly illuminated leaves that contribute disproportionately to canopy photosynthesis are warmed to the point that leaf gas exchange is curtailed. | |||||
BibTeX:
@article{doughty_are_2008, author = {Doughty, Christopher E. and Goulden, Michael L.}, title = {Are tropical forests near a high temperature threshold?}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000260178600001 http://www.agu.org/pubs/crossref/2008/2007JG000632.shtml}, doi = {https://doi.org/10.1029/2007jg000632} } |
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Doughty, C.E. and Goulden, M.L. | Seasonal patterns of tropical forest leaf area index and CO(2) exchange | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: We used in situ and satellite measurements to investigate the seasonal patterns of leaf area index (LAI) and gross ecosystem CO(2) exchange ( GEE) by an evergreen tropical forest. The forest experienced a dry season from June through November. The rates of light-saturated CO(2) uptake ( GEE) were comparatively high from December through March and low from May through July. In situ measurements showed that LAI varied seasonally, with a minimum from May through September. Leaf production and leaf abscission were reduced from December through April. Leaf abscission increased in May, which reduced LAI. High rates of leaf abscission and production occurred from July through September associated with leaf turnover. Leaf abscission decreased abruptly in October, while production continued, which rapidly increased LAI. Leaf phenology was not directly correlated with changes in soil water. The seasonal cycle of in situ LAI differed markedly from the seasonal cycles of in situ normalized difference vegetation index (NDVI) and the Moderate Resolution Imaging Spectroradiometer (MODIS) MOD15 LAI product. We hypothesize that the NDVI and MOD15 seasonality at the site is driven partly by seasonal changes in leaf age and leaf reflectance. We developed three simple models to investigate the causes of GEE seasonality. The first two models showed that the seasonal changes in LAI alone, and the effects of leaf age on leaf-level photosynthesis alone, could not account for the observed GEE seasonality. The third model showed that the combined effect of seasonal changes in LAI and seasonal changes in leaf age and leaf photosynthesis was sufficient to account for the observed GEE seasonality. | |||||
BibTeX:
@article{doughty_seasonal_2008, author = {Doughty, Christopher E. and Goulden, Michael L.}, title = {Seasonal patterns of tropical forest leaf area index and CO(2) exchange}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000260178500001}, doi = {https://doi.org/10.1029/2007jg000590} } |
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Doughty, C.E., Goldsmith, G.R., Raab, N., Girardin, C.A.J., Farfan-Amezquita, F., Huaraca-Huasco, W., Silva-Espejo, J.E., Araujo-Murakami, A., da Costa, A.C.L., Rocha, W., Galbraith, D., Meir, P., Metcalfe, D.B. and Malhi, Y. | What controls variation in carbon use efficiency among Amazonian tropical forests? | 2018 | Biotropica Vol. 50(1), pp. 16-25 |
article | DOI URL |
Abstract: Abstract Why do some forests produce biomass more efficiently than others? Variations in Carbon Use Efficiency (CUE: total Net Primary Production (NPP)/ Gross Primary Production (GPP)) may be due to changes in wood residence time (Biomass/NPPwood), temperature, or soil nutrient status. We tested these hypotheses in 14, one ha plots across Amazonian and Andean forests where we measured most key components of net primary production (NPP: wood, fine roots, and leaves) and autotrophic respiration (Ra; wood, rhizosphere, and leaf respiration). We found that lower fertility sites were less efficient at producing biomass and had higher rhizosphere respiration, indicating increased carbon allocation to belowground components. We then compared wood respiration to wood growth and rhizosphere respiration to fine root growth and found that forests with residence times textless40 yrs had significantly lower maintenance respiration for both wood and fine roots than forests with residence times textgreater40 yrs. A comparison of rhizosphere respiration to fine root growth showed that rhizosphere growth respiration was significantly greater at low fertility sites. Overall, we found that Amazonian forests produce biomass less efficiently in stands with residence times textgreater40 yrs and in stands with lower fertility, but changes to long-term mean annual temperatures do not impact CUE. | |||||
BibTeX:
@article{doughty_what_2018, author = {Doughty, Christopher E. and Goldsmith, Gregory R. and Raab, Nicolas and Girardin, Cecile A. J. and Farfan-Amezquita, Filio and Huaraca-Huasco, Walter and Silva-Espejo, Javier E. and Araujo-Murakami, Alejandro and da Costa, Antonio C. L. and Rocha, Wanderley and Galbraith, David and Meir, Patrick and Metcalfe, Dan B. and Malhi, Yadvinder}, title = {What controls variation in carbon use efficiency among Amazonian tropical forests?}, journal = {Biotropica}, year = {2018}, volume = {50}, number = {1}, pages = {16--25}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/btp.12504}, doi = {https://doi.org/10.1111/btp.12504} } |
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Doughty, C.E., Flanner, M.G. and Goulden, M.L. | Effect of smoke on subcanopy shaded light, canopy temperature, and carbon dioxide uptake in an Amazon rainforest | 2010 | Global Biogeochemical Cycles Vol. 24 |
article | DOI URL |
Abstract: Daytime Net Ecosystem CO(2) uptake (NEE) in an Amazon forest has been shown to increase significantly during smoky periods associated with biomass burning. We investigated whether the increase in CO(2) uptake is caused by increased irradiance in the lower canopy, which results from increased above-canopy diffuse light, or by decreased canopy temperature, which results from decreased above-canopy net radiation. We used Sun photometers measuring aerosol optical depth to find nonsmoky (Aerosol Optical Depth (AOT) textless 0.35), smoky (AOT textgreater 0.5) and very smoky (AOT textgreater 0.7) periods for the Tapajos region in the Amazon. Using a network of subcanopy photosynthetic photon flux density (PPFD) sensors, we detected a similar to 4 mu mol m(-2) s(-1) increase in subcanopy diffuse light during smoky periods relative to nonsmoky periods. Using a pyrgeometer to measure upwelling longwave radiation and, hence, canopy surface temperature, we found a similar to 0.5 degrees C cooling relative to air temperature during smoky periods. We modeled subcanopy irradiance based on the subcanopy PPFD sensors and combined this with subcanopy leaf photosynthesis measurements to determine how the increased lower canopy light affected NEE. We used the relationship between temperature and NEE measured by eddy covariance to determine the effect of decreased canopy temperature on canopy CO(2) uptake. We found that the increase in CO(2) uptake at high aerosol optical depths is primarily a result of increased shaded light in the subcanopy (accounting for similar to 80%) and to a lesser extent the effect of decreased canopy temperature (accounting for similar to 20%). | |||||
BibTeX:
@article{doughty_effect_2010, author = {Doughty, Christopher E. and Flanner, Mark G. and Goulden, Michael L.}, title = {Effect of smoke on subcanopy shaded light, canopy temperature, and carbon dioxide uptake in an Amazon rainforest}, journal = {Global Biogeochemical Cycles}, year = {2010}, volume = {24}, url = {://WOS:000280585700001}, doi = {https://doi.org/10.1029/2009gb003670} } |
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Doughty, C.E., Field, C.B. and McMillan, A.M.S. | Can crop albedo be increased through the modification of leaf trichomes, and could this cool regional climate? | 2011 | Climatic Change Vol. 104(2), pp. 379-387 |
article | DOI URL |
Abstract: Managing the land surface to increase albedo to offset regional warming has received less attention than managing the land surface to sequester carbon. We test whether increasing agricultural albedo can cool regional climate. We first used the Community Atmosphere Model (CAM 3.0) coupled to the Community Land Model (CLM 3.0) to assess the broad climatic effects of a hypothetical implementation of a strategy in which the albedo of cropland regions is increased using high albedo crops. Simulations indicate that planting brighter crops can decrease summertime maximum daily 2 m air temperature by 0.25A degrees C per 0.01 increase in surface albedo at high latitudes (textgreater 30A degrees). However, planting brighter crops at low latitudes (textless 30A degrees) may have negative repercussions including warming the land surface and decreasing precipitation, because increasing the land surface albedo tends to preferentially decrease latent heat fluxes to the atmosphere, which decreases cloud cover and rainfall. We then test a possible method for increasing crop albedo by measuring the range of albedo within 16 isolines of soybeans that differ only with trichome color, orientation, and density but find that such modifications had only minor impacts on leaf albedo. Increasing agricultural albedo may cool high latitude regional climate, but increasing plant albedo sufficiently to offset potential future warming will require larger changes to plant albedo than are currently available. | |||||
BibTeX:
@article{doughty_can_2011, author = {Doughty, Christopher E. and Field, Christopher B. and McMillan, Andrew M. S.}, title = {Can crop albedo be increased through the modification of leaf trichomes, and could this cool regional climate?}, journal = {Climatic Change}, year = {2011}, volume = {104}, number = {2}, pages = {379--387}, url = {://WOS:000286116900011 http://www.springerlink.com/content/311r7qj46046481u/fulltext.pdf}, doi = {https://doi.org/10.1007/s10584-010-9936-0} } |
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Doughty, C.E., Asner, G.P. and Martin, R.E. | Predicting tropical plant physiology from leaf and canopy spectroscopy | 2010 | Oecologia Vol. 165(2), pp. 289-299 |
article | DOI URL |
Abstract: A broad regional understanding of tropical forest leaf photosynthesis has long been a goal for tropical forest ecologists, but it has remained elusive due to difficult canopy access and high species diversity. Here we develop an empirical model to predict sunlit, light-saturated, tropical leaf photosynthesis using leaf and simulated canopy spectra. To develop this model, we used partial least squares (PLS) analysis on three tropical forest datasets (159 species), two in Hawaii and one at the biosphere 2 laboratory (B2L). For each species, we measured light-saturated photosynthesis (A), light and CO(2) saturated photosynthesis (A (max)), respiration (R), leaf transmittance and reflectance spectra (400-2,500 nm), leaf nitrogen, chlorophyll a and b, carotenoids, and leaf mass per area (LMA). The model best predicted A [r (2) = 0.74, root mean square error (RMSE) = 2.9 mu mol m(-2) s(-1))] followed by R (r (2) = 0.48), and A (max) (r (2) = 0.47). We combined leaf reflectance and transmittance with a canopy radiative transfer model to simulate top-of-canopy reflectance and found that canopy spectra are a better predictor of A (RMSE = 2.5 +/- A 0.07 mu mol m(-2) s(-1)) than are leaf spectra. The results indicate the potential for this technique to be used with high-fidelity imaging spectrometers to remotely sense tropical forest canopy photosynthesis. | |||||
BibTeX:
@article{doughty_predicting_2010, author = {Doughty, Christopher E. and Asner, Gregory P. and Martin, Roberta E.}, title = {Predicting tropical plant physiology from leaf and canopy spectroscopy}, journal = {Oecologia}, year = {2010}, volume = {165}, number = {2}, pages = {289--299}, note = {Edition: 2010/10/22}, url = {://WOS:000286224900004}, doi = {https://doi.org/10.1007/s00442-010-1800-4} } |
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Doughty, C.E. | An In Situ Leaf and Branch Warming Experiment in the Amazon | 2011 | Biotropica Vol. 43(6), pp. 658-665 |
article | DOI URL |
Abstract: Leaves and branches of mature trees, lianas, and gap species were warmed in an Amazonian forest for 4 mo to observe the effect of warming on photosynthesis, stomatal conductance, and transpiration. Electric resistance heaters increased air temperatures near the leaves by approximately 2 degrees C. Sunlit leaf temperatures increased by 2-3 degrees C on average, but during some periods leaf temperatures increased by textgreater5 degrees C. Maximum photosynthesis (A(max)) decreased significantly in the warmed leaves vs. the control leaves over the 13-wk study period with an average decrease in A(max) of 1.4 mu mol/m(2)s (19% decrease from a mean A(max) of 7.2 mu mol/m(2)s) when measured at 30 degrees C and there were no signs of acclimation to higher temperatures within existing leaves. The decline in A(max) was likely due to irreversible temperature damage caused by very high leaf temperatures and not due to C(i) limitation of carboxylation. Warming had a larger negative impact on A(max) in canopy level tree species than other tested functional groups such as lianas or gap species. Transpiration did not significantly increase in the warmed leaves compared with the control group. This study indicates that increased temperatures due to global warming could potentially decrease future tropical forest carbon uptake by a significant amount. | |||||
BibTeX:
@article{doughty_situ_2011, author = {Doughty, Christopher E.}, title = {An In Situ Leaf and Branch Warming Experiment in the Amazon}, journal = {Biotropica}, year = {2011}, volume = {43}, number = {6}, pages = {658--665}, url = {://WOS:000296909800003}, doi = {https://doi.org/10.1111/j.1744-7429.2010.00746.x} } |
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Doughty, C., Metcalfe, D., Girard, C., Amesquita, F., Durand, L., Huasco, W., Silva-Espejo, J., Murakami, A., Costa, M., Costa, A., Rocha, W., Meir, P., Galbarith, D. and Malhi, Y. | Source and sink carbono dynamics and carbono allocation in the Amazon basin [BibTeX] |
2015 | Global Biogeochemical Cycles Vol. 29 |
article | DOI |
BibTeX:
@article{doughty_source_2015, author = {Doughty, CE. and Metcalfe, DB. and Girard, CAJ. and Amesquita, FF and Durand, L and Huasco, WH. and Silva-Espejo, JE. and Murakami, AA. and Costa, MC. and Costa, ACL. and Rocha, W. and Meir, P. and Galbarith, D. and Malhi, Y.}, title = {Source and sink carbono dynamics and carbono allocation in the Amazon basin}, journal = {Global Biogeochemical Cycles}, year = {2015}, volume = {29}, doi = {https://doi.org/10.1002/2014GB005028} } |
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dos Santos, L., Magnabosco Marra, D., Trumbore, S., Camargo, P.d. and R.I. Negrón-Juárez G.H.P.M. Ribeiro, J.d.S.N.H.A.L. | Windthrows increase soil carbon stocks in a central Amazon forest [BibTeX] |
2016 | Biogeosciences Vol. 13, pp. 1299-1308 |
article | DOI |
BibTeX:
@article{dos_santos_windthrows_2016, author = {dos Santos, L.T. and Magnabosco Marra, D. and Trumbore, S. and Camargo, P.B. de and R.I. Negrón-Juárez, G.H.P.M. Ribeiro, J. dos Santos, N. Higuchi, A.J.N. Lima}, title = {Windthrows increase soil carbon stocks in a central Amazon forest}, journal = {Biogeosciences}, year = {2016}, volume = {13}, pages = {1299--1308}, doi = {https://doi.org/10.5194/bg-13-1299-2016} } |
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Domingues, T.F., Ometto, J.P.H.B., Nepstad, D.C., Brando, P.M., Martinelli, L.A. and Ehleringer, J.R. | Ecophysiological plasticity of Amazonian trees to long-term drought [BibTeX] |
2018 | Oecologia Vol. 187(4), pp. 933-940 |
article | |
BibTeX:
@article{domingues_ecophysiological_2018, author = {Domingues, Tomas Ferreira and Ometto, Jean Pierre Henry Balbaud and Nepstad, Daniel C. and Brando, Paulo M. and Martinelli, Luiz Antonio and Ehleringer, James R.}, title = {Ecophysiological plasticity of Amazonian trees to long-term drought}, journal = {Oecologia}, year = {2018}, volume = {187}, number = {4}, pages = {933--940} } |
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Domingues, T.F., Martinelli, L.A. and Ehleringer, J.R. | Seasonal patterns of leaf-level photosynthetic gas exchange in an eastern Amazonian rain forest [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 189-203 |
article | |
BibTeX:
@article{domingues_seasonal_2014, author = {Domingues, Tomas F. and Martinelli, Luiz A. and Ehleringer, James R.}, title = {Seasonal patterns of leaf-level photosynthetic gas exchange in an eastern Amazonian rain forest}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {189--203} } |
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Domingues, T.F., Martinelli, L.A. and Ehleringer, J.R. | Ecophysiological traits of plant functional groups in forest and pasture ecosystems from eastern Amazonia, Brazil | 2007 | Plant Ecology Vol. 193(1), pp. 101-112 |
article | DOI URL |
Abstract: The plant functional group approach has the potential to clarify ecological patterns and is of particular importance in simplifying the application of ecological models in high biodiversity ecosystems. Six functional groups (pasture grass, pasture sapling, top-canopy tree, top-canopy liana, mid canopy tree, and understory tree) were established a priori based on ecosystem inhabited, life form, and position within the forest canopy profile on eastern Amazonian region. Ecophysiological traits related to photosynthetic gas exchange were then used to characterize such groups. The ecophysiological traits evaluated showed considerable variations among groups. The pasture grass functional group (a C(4) photosynthetic pathway species) showed high instantaneous water use efficiency (A (max)/g (s)@A (max)), high photosynthetic nitrogen use efficiency (A (max)/N (area)), and high ratio of A (max) to dark respiration (A (max)/R (d)). Among the species with the C(3) photosynthetic pathway, the top-canopy liana group showed the highest mean of A (max)/g (s)@A (max), statistically distinct from the lowest average presented by the understory tree group. Furthermore, the pasture sapling group showed the lowest average of A (max)/R (d), statistically distinct from the high average observed for the understory tree group. Welch-ANOVAs followed by Games-Howell post hoc tests applied to ecophysiological traits produced reasonable distinctions among functional groups, although no significant distinction was detected between the groups top-canopy tree and pasture sapling. Species distribution within the functional groups was accurately reproduced by discriminant analyses based on species averages of ecophysiological traits. The present work convincingly shows that the functional groups identified have distinct ecophysiological characteristics, with the potential to respond differently to environmental factors. Such information is of great importance in modeling efforts that evaluate the effects of dynamic changes in tropical plant communities over ecosystem primary productivity. | |||||
BibTeX:
@article{domingues_ecophysiological_2007, author = {Domingues, Tomas F. and Martinelli, Luiz A. and Ehleringer, James R.}, title = {Ecophysiological traits of plant functional groups in forest and pasture ecosystems from eastern Amazonia, Brazil}, journal = {Plant Ecology}, year = {2007}, volume = {193}, number = {1}, pages = {101--112}, url = {://WOS:000249802700008}, doi = {https://doi.org/10.1007/s11258-006-9251-z} } |
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Domingues, T.F., Berry, J.A., Martinelli, L.A., Ometto, J.P.H.B. and Ehleringer, J.R. | Parameterization of canopy structure and leaf-level gas exchange for an eastern Amazonian tropical rain forest (Tapajos National Forest, Para, Brazil) | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: Carbon flux of Amazonian primary forest vegetation has been shown to vary both spatially and temporally. Process-based models are adequate tools to understand the basis of such variation and can also provide projections to future scenarios. The parameterization of such process-based models requires information from the vegetation in question simply because ecosystem-level gas exchange is a direct result of the tightly coupled interaction between local vegetation and regional climate. In this study, data are presented concerning canopy structure [ leaf area index (LAI), and the ratio of leaf dry mass to leaf area (LMA)], leaf chemistry [area-based foliar nitrogen content (N(area)) and carbon isotope composition (delta(13)C)], and photosynthetic gas exchange [ maximum carbon assimilation rates (A(max)), stomatal conductance (g(s)@A(max)), maximum carboxylation capacity (V(cmax)), and respiration rates (R(d))] versus relative height from an extensive survey of primary forest vegetation of the Santarem region ( eastern Amazon, Santarem, Federal State of Para, Brazil). Ground-level LAI values ranged between 4.5 and 5.9. Both A(max) and V(cmax) showed large variations within the canopy profile with values ranging between 2.4 and 15.7 mu mol m(-2) s(-1) and between 10.1 and 105.7 mu mol m(-2) s(-1), respectively. Also, N(area) varied between 0.75 to 4.19 gN m(-2), and similar to A(max) and V(cmax), showed higher values at the top of the canopy. Variations were detected among sites in patterns of vertical distribution of N(area) and LAI, indicating spatial heterogeneity of the forest. Also, no statistically significant evidence of seasonal variations on parameters was observed, indicating that there is limited gas exchange acclimation by the vegetation to wet or dry seasons. | |||||
BibTeX:
@article{domingues_parameterization_2005, author = {Domingues, Tomas F. and Berry, Joseph A. and Martinelli, Luiz A. and Ometto, Jean P. H. B. and Ehleringer, James R.}, title = {Parameterization of canopy structure and leaf-level gas exchange for an eastern Amazonian tropical rain forest (Tapajos National Forest, Para, Brazil)}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241214500001} } |
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Domingues Mendes-Jr, O., Chou, S. and Sá L.D.A. & Manzi, A.M. | Análise das condições atmosféricas durante a segunda campanha do Experimento Interdisciplinar do Pantanal Sul Mato-grossense. [BibTeX] |
2004 | Revista Brasileira de Meteorologia Vol. 19, pp. 73-88 |
article | |
BibTeX:
@article{domingues_alise_2004, author = {Domingues, Mendes-Jr, O.; Chou, S.C.; Sá, L.D.A. & Manzi, A.O., M.O.}, title = {Análise das condições atmosféricas durante a segunda campanha do Experimento Interdisciplinar do Pantanal Sul Mato-grossense.}, journal = {Revista Brasileira de Meteorologia}, year = {2004}, volume = {19}, pages = {73--88} } |
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Dolman, A.J., Schulze, E.D. and Valentini, R. | Analyzing carbon flux measurements [BibTeX] |
2003 | Science Vol. 301(5635), pp. 916-916 |
article | DOI URL |
BibTeX:
@article{dolman_analyzing_2003, author = {Dolman, A. J. and Schulze, E. D. and Valentini, R.}, title = {Analyzing carbon flux measurements}, journal = {Science}, year = {2003}, volume = {301}, number = {5635}, pages = {916--916}, note = {Edition: 2003/08/16}, url = {://WOS:000184755900014}, doi = {https://doi.org/10.1126/science.301.5635.916b} } |
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Dolman, A.J., Dias, M.A.S., Calvet, J.C., Ashby, M., Tahara, A.S., Delire, C., Kabat, P., Fisch, G.A. and Nobre, C.A. | Meso-scale effects of tropical deforestation in Amazonia: preparatory LBA modelling studies | 1999 | Annales Geophysicae-Atmospheres Hydrospheres and Space Sciences Vol. 17(8), pp. 1095-1110 |
article | DOI URL |
Abstract: As part of the preparation for the Large-Scale Biosphere Atmosphere Experiment in Amazonia, a meso-scale modelling study was executed to highlight deficiencies in the current understanding of land surface atmosphere interaction at local to sub-continental scales in the dry season. Meso-scale models were run in 1-D and 3-D mode for the area of Rondonia State, Brazil. The important conclusions are that without calibration it is difficult to model the energy partitioning of pasture; modelling that of forest is easier due to the absence of a strong moisture deficit signal. The simulation of the boundary layer above forest is good, above deforested areas (pasture) poor. The models' underestimate of the temperature of the boundary layer is likely to be caused by the neglect of the radiative effects of aerosols caused by biomass burning, but other factors such as lack of sufficient entrainment in the model at the mixed layer top may also contribute. The Andes generate patterns of subsidence and gravity waves, the effects of which are felt far into the Rondonian area. The results show that the picture presented by GCM modelling studies may need to be balanced by an increased understanding of what happens at the meso-scale. The results are used to identify key measurements for the LBA atmospheric meso-scale campaign needed to improve the model simulations. Similar modelling studies are proposed for the wet season in Rondonia, when convection plays a major role. | |||||
BibTeX:
@article{dolman_meso-scale_1999, author = {Dolman, A. J. and Dias, M. A. S. and Calvet, J. C. and Ashby, M. and Tahara, A. S. and Delire, C. and Kabat, P. and Fisch, G. A. and Nobre, C. A.}, title = {Meso-scale effects of tropical deforestation in Amazonia: preparatory LBA modelling studies}, journal = {Annales Geophysicae-Atmospheres Hydrospheres and Space Sciences}, year = {1999}, volume = {17}, number = {8}, pages = {1095--1110}, url = {://WOS:000082294000010}, doi = {https://doi.org/10.1007/s00585-999-1095-0} } |
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D'Oliveira, F.A.F., Cohen, J.C.P., Spracklen, D.V., Medeiros, A.S.S., Cirino, G.G., Artaxo, P. and Dias-Júnior, C.Q. | Simulation of the effects of biomass burning in a mesoscale convective system in the central amazon | 2022 | Atmospheric Research Vol. 278, pp. 106345 |
article | DOI URL |
Abstract: During the dry season of 2014, the formation of a mesoscale convective system (MCS) caused intense precipitation and strong winds in the central Amazon region. In this period, cases of MCS that occurred during the days when there were higher concentrations of CO were analyzed. Through this criterion, a case of MCS occurred on August 16th, 2014 was selected. We used the chemical-atmospheric model WRF-Chem to assess the influence of biomass burning aerosol on the intensity of precipitation, winds, vertical and horizontal transport associated with this convective system. We show that biomass burning aerosol reduces the strength of the mesoscale convective system, with less vertical and horizontal transport of carbon monoxide and ozone. In the absence of biomass burning aerosol downdrafts and precipitation rate are more intense, and cloud development up to 5 km is more developed, making the horizontal flow and vertical transport of ozone more intense, however, much more efficient in reducing the concentrations of other gases. | |||||
BibTeX:
@article{doliveira_simulation_2022, author = {D'Oliveira, Flávio A. F. and Cohen, Julia C. P. and Spracklen, Dominick V. and Medeiros, Adan S. S. and Cirino, Glauber G. and Artaxo, Paulo and Dias-Júnior, Cleo Q.}, title = {Simulation of the effects of biomass burning in a mesoscale convective system in the central amazon}, journal = {Atmospheric Research}, year = {2022}, volume = {278}, pages = {106345}, url = {https://www.sciencedirect.com/science/article/pii/S0169809522003313}, doi = {https://doi.org/10.1016/j.atmosres.2022.106345} } |
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Docherty, E.M., Gloor, E., Sponchiado, D., Gilpin, M., Pinto, C.A.D., Junior, H.M., Coughlin, I., Ferreira, L., Junior, J.A.S., da Costa, A.C.L., Meir, P. and Galbraith, D. | Long-term drought effects on the thermal sensitivity of Amazon forest trees | 2023 | Plant, Cell & Environment Vol. 46(1), pp. 185-198 |
article | DOI URL |
Abstract: Abstract The continued functioning of tropical forests under climate change depends on their resilience to drought and heat. However, there is little understanding of how tropical forests will respond to combinations of these stresses, and no field studies to date have explicitly evaluated whether sustained drought alters sensitivity to temperature. We measured the temperature response of net photosynthesis, foliar respiration and the maximum quantum efficiency of photosystem II (Fv/Fm) of eight hyper-dominant Amazonian tree species at the world's longest-running tropical forest drought experiment, to investigate the effect of drought on forest thermal sensitivity. Despite a 0.6°C–2°C increase in canopy air temperatures following long-term drought, no change in overall thermal sensitivity of net photosynthesis or respiration was observed. However, photosystem II tolerance to extreme-heat damage (T50) was reduced from 50.0 ± 0.3°C to 48.5 ± 0.3°C under drought. Our results suggest that long-term reductions in precipitation, as projected across much of Amazonia by climate models, are unlikely to greatly alter the response of tropical forests to rising mean temperatures but may increase the risk of leaf thermal damage during heatwaves. | |||||
BibTeX:
@article{docherty_long-term_2023, author = {Docherty, Emma M. and Gloor, Emanuel and Sponchiado, Daniela and Gilpin, Martin and Pinto, Carlos A. D. and Junior, Haroldo M. and Coughlin, Ingrid and Ferreira, Leandro and Junior, João A. S. and da Costa, Antonio C. L. and Meir, Patrick and Galbraith, David}, title = {Long-term drought effects on the thermal sensitivity of Amazon forest trees}, journal = {Plant, Cell & Environment}, year = {2023}, volume = {46}, number = {1}, pages = {185--198}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/pce.14465}, doi = {https://doi.org/10.1111/pce.14465} } |
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Dlugi, R., Berger, M., Mallik, C., Tsokankunku, A., Zelger, M., Acevedo, O.C., Bourtsoukidis, E., Hofzumahaus, A., Kesselmeier, J., Kramm, G., Marno, D., Martinez, M., Nölscher, A.C., Ouwersloot, H., Pfannerstill, E.Y., Rohrer, F., Tauer, S., Williams, J., Yáñez-Serrano, A.M., Andreae, M.O., Harder, H. and Sörgel, M. | Segregation in the Atmospheric Boundary Layer: The Case of OH - Isoprene [BibTeX] |
2019 | Atmos. Chem. Phys. Discuss. Vol. 2019, pp. 1-61 |
article | DOI URL |
BibTeX:
@article{dlugi_segregation_2019, author = {Dlugi, R. and Berger, M. and Mallik, C. and Tsokankunku, A. and Zelger, M. and Acevedo, O. C. and Bourtsoukidis, E. and Hofzumahaus, A. and Kesselmeier, J. and Kramm, G. and Marno, D. and Martinez, M. and Nölscher, A. C. and Ouwersloot, H. and Pfannerstill, E. Y. and Rohrer, F. and Tauer, S. and Williams, J. and Yáñez-Serrano, A. M. and Andreae, M. O. and Harder, H. and Sörgel, M.}, title = {Segregation in the Atmospheric Boundary Layer: The Case of OH - Isoprene}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2019}, volume = {2019}, pages = {1--61}, url = {https://acp.copernicus.org/preprints/acp-2018-1325/}, doi = {https://doi.org/10.5194/acp-2018-1325} } |
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Dinkelmeyer, H., Lehmann, J., Renck, A., Trujillo, L., da Silva, J.P., Gebauer, G. and Kaiser, K. | Nitrogen uptake from N-15-enriched fertilizer by four tree crops in an Amazonian agroforest | 2003 | Agroforestry Systems Vol. 57(3), pp. 213-224 |
article | DOI URL |
Abstract: Mixed tree cropping systems have been proposed for sustainable nutrient management in the humid tropics. Yet, the nutrient interactions between intercropped trees have not been addressed sufficiently. In the present study we compare the temporal and spatial patterns of the uptake of applied N-15 by four different tree crops in a mixed tree cropping system on a Xanthic Ferralsol in central Amazonia, Brazil, during one year. Most of the N uptake occurred during the first two weeks. Very little N was recovered by peach palm (Bactris gasipaes), more by cupuassu (Theobroma grandiflorum) and annatto (Bixa orellana) and most by Brazil nut (Bertholletia excelsa). Due to tree pruning the total accumulation of applied N-15 in the above-ground biomass of annatto decreased throughout the year. It remained constant in cupuassu and peach palm and increased in Brazil nut. Brazil nut showed an extensive root activity and took up more fertilizer N applied to neighboring trees than from the one applied under its own canopy in contrast to the other three tree crops. Therefore, trees with wide-spread root systems may not need to receive N fertilizer directly but can take up N applied to other trees in the mixed cropping system. This means that such trees may effectively decrease N leaching when intercropped with trees that have dormant periods or places with low N uptake, but also exert considerable resource competition. | |||||
BibTeX:
@article{dinkelmeyer_nitrogen_2003, author = {Dinkelmeyer, H. and Lehmann, J. and Renck, A. and Trujillo, L. and da Silva, J. P. and Gebauer, G. and Kaiser, K.}, title = {Nitrogen uptake from N-15-enriched fertilizer by four tree crops in an Amazonian agroforest}, journal = {Agroforestry Systems}, year = {2003}, volume = {57}, number = {3}, pages = {213--224}, url = {://WOS:000184336900005}, doi = {https://doi.org/10.1023/a:1024824108549} } |
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DiMaria, C.A., Jones, D.B.A., Worden, H., Bloom, A.A., Bowman, K., Stavrakou, T., Miyazaki, K., Worden, J., Guenther, A., Sarkar, C., Seco, R., Park, J.-H., Tota, J., Alves, E.G. and Ferracci, V. | Optimizing the Isoprene Emission Model MEGAN With Satellite and Ground-Based Observational Constraints | 2023 | Journal of Geophysical Research: Atmospheres Vol. 128(4), pp. e2022JD037822 |
article | DOI URL |
Abstract: Abstract Isoprene is a hydrocarbon emitted in large quantities by terrestrial vegetation. It is a precursor to several air quality and climate pollutants including ozone. Emission rates vary with plant species and environmental conditions. This variability can be modeled using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). MEGAN parameterizes isoprene emission rates as a vegetation-specific standard rate which is modulated by scaling factors that depend on meteorological and environmental driving variables. Recent experiments have identified large uncertainties in the MEGAN temperature response parameterization, while the emission rates under standard conditions are poorly constrained in some regions due to a lack of representative measurements and uncertainties in landcover. In this study, we use Bayesian model-data fusion to optimize the MEGAN temperature response and standard emission rates using satellite- and ground-based observational constraints. Optimization of the standard emission rate with satellite constraints reduced model biases but was highly sensitive to model input errors and drought stress and was found to be inconsistent with ground-based constraints at an Amazonian field site, reflecting large uncertainties in the satellite-based emissions. Optimization of the temperature response with ground-based constraints increased the temperature sensitivity of the model by a factor of five at an Amazonian field site but had no impact at a UK field site, demonstrating significant ecosystem-dependent variability of the isoprene emission temperature sensitivity. Ground-based measurements of isoprene across a wide range of ecosystems will be key for obtaining an accurate representation of isoprene emission temperature sensitivity in global biogeochemical models. | |||||
BibTeX:
@article{dimaria_optimizing_2023, author = {DiMaria, Christian A. and Jones, Dylan B. A. and Worden, Helen and Bloom, A. Anthony and Bowman, Kevin and Stavrakou, Trissevgeni and Miyazaki, Kazuyuki and Worden, John and Guenther, Alex and Sarkar, Chinmoy and Seco, Roger and Park, Jeong-Hoo and Tota, Julio and Alves, Eliane Gomes and Ferracci, Valerio}, title = {Optimizing the Isoprene Emission Model MEGAN With Satellite and Ground-Based Observational Constraints}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2023}, volume = {128}, number = {4}, pages = {e2022JD037822}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2022JD037822}, doi = {https://doi.org/10.1029/2022JD037822} } |
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Dias-Júnior, C., Sá, L.D., Marques Filho, E.P., Santana, R.A., Mauder, M. and Manzi, A.O. | Turbulence regimes in the stable boundary layer above and within the Amazon forest [BibTeX] |
2017 | Agricultural and Forest Meteorology Vol. 233, pp. 122-132 |
article | DOI |
BibTeX:
@article{dias-junior_turbulence_2017, author = {Dias-Júnior, C.Q. and Sá, L. D.A. and Marques Filho, E. P. and Santana, R. A. and Mauder, M. and Manzi, A. O.}, title = {Turbulence regimes in the stable boundary layer above and within the Amazon forest}, journal = {Agricultural and Forest Meteorology}, year = {2017}, volume = {233}, pages = {122--132}, doi = {https://doi.org/10.1016/j.agrformet.2016.11.001} } |
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Dias-Junior, C.Q., Marques Filho, E.P. and Sá, L.D. | A large eddy simulation model applied to analyze the turbulent flow above Amazonforest [BibTeX] |
2015 | J. Wind Eng. Ind. Aerodyn. Vol. 147, pp. 143-153 |
article | |
BibTeX:
@article{dias-junior_large_2015, author = {Dias-Junior, Cleo Q. and Marques Filho, Edson P. and Sá, Leonardo D.A.}, title = {A large eddy simulation model applied to analyze the turbulent flow above Amazonforest}, journal = {J. Wind Eng. Ind. Aerodyn.}, year = {2015}, volume = {147}, pages = {143--153} } |
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Dias-Junior, C.Q., Dias, N.L., Fuentes, J.D. and Chamecki, M. | Convective storms and non-classical low-level jets during high ozone level episodes in the Amazon region: An ARM/GOAMAZON case study [BibTeX] |
2017 | Atmospheric Environment | article | DOI |
BibTeX:
@article{dias-junior_convective_2017, author = {Dias-Junior, Cléo Q. and Dias, Nelson Luís and Fuentes, José D. and Chamecki, Marcelo}, title = {Convective storms and non-classical low-level jets during high ozone level episodes in the Amazon region: An ARM/GOAMAZON case study}, journal = {Atmospheric Environment}, year = {2017}, doi = {https://doi.org/10.1016/j.atmosenv.2017.02.006} } |
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Dias-Júnior, C.Q., Dias, N.L., dos Santos, R.M.N., Sörgel, M., Araújo, A., Tsokankunku, A., Ditas, F., de Santana, R.A., von Randow, C., Sá, M., Pöhlker, C., Toledo Machado, L.A., de Sá, L.D., Moran-Zuloaga, D., Janssen, R., Acevedo, O., Oliveira, P., Fisch, G., Chor, T. and Manzi, A. | Is There a Classical Inertial Sublayer Over the Amazon Forest? | 2019 | Geophysical Research Letters Vol. 46(10), pp. 5614-5622 |
article | DOI URL |
Abstract: Abstract On the basis of measurements over different surfaces, an inertial sublayer (ISL), where Monin-Obukhov Similarity Theory applies, exists above z=3h, where h is canopy height. The roughness sublayer is within htextlessztextless3h. Most studies of the surface layer above forests, however, are able to probe only a narrow region above h. Therefore, direct verification of an ISL above tall forests is difficult. In this study we conducted a systematic analysis of unstable turbulence characteristics at heights from 40 to 325 m, measured at an 80m, and the recently built 325-m Amazon Tall Tower Observatory towers over the Amazon forest. Our analyses have revealed no indication of the existence of an ISL; instead, the roughness sublayer directly merges with the convective mixed layer above. Implications for estimates of momentum and scalar fluxes in numerical models and observational studies can be significant. | |||||
BibTeX:
@article{dias-junior_is_2019, author = {Dias-Júnior, Cléo Quaresma and Dias, Nelson Luís and dos Santos, Rosa Maria N. and Sörgel, Matthias and Araújo, Alessandro and Tsokankunku, Anywhere and Ditas, Florian and de Santana, Raoni Aquino and von Randow, Celso and Sá, Marta and Pöhlker, Christopher and Toledo Machado, Luiz Augusto and de Sá, Leonardo Deane and Moran-Zuloaga, Daniel and Janssen, Ruud and Acevedo, Otávio and Oliveira, Pablo and Fisch, Gilberto and Chor, Tomas and Manzi, Antonio}, title = {Is There a Classical Inertial Sublayer Over the Amazon Forest?}, journal = {Geophysical Research Letters}, year = {2019}, volume = {46}, number = {10}, pages = {5614--5622}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL083237}, doi = {https://doi.org/10.1029/2019GL083237} } |
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Dias-Júnior, C.Q., Carneiro, R.G., Fisch, G., D’Oliveira, F.A.F., Sörgel, M., Botía, S., Machado, L.A.T., Wolff, S., Santos, R.M.N.d. and Pöhlker, C. | Intercomparison of Planetary Boundary Layer Heights Using Remote Sensing Retrievals and ERA5 Reanalysis over Central Amazonia [BibTeX] |
2022 | Remote Sensing Vol. 14(18), pp. 4561 |
article | URL |
BibTeX:
@article{dias-junior_intercomparison_2022, author = {Dias-Júnior, Cléo Quaresma and Carneiro, Rayonil Gomes and Fisch, Gilberto and D’Oliveira, Flávio Augusto F. and Sörgel, Matthias and Botía, Santiago and Machado, Luiz Augusto T. and Wolff, Stefan and Santos, Rosa Maria N. dos and Pöhlker, Christopher}, title = {Intercomparison of Planetary Boundary Layer Heights Using Remote Sensing Retrievals and ERA5 Reanalysis over Central Amazonia}, journal = {Remote Sensing}, year = {2022}, volume = {14}, number = {18}, pages = {4561}, url = {https://www.mdpi.com/2072-4292/14/18/4561} } |
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Dias, V.R.M., Sanches, L., Alves, M. and Nogueira, J. | Spatio-temporal variability of anions in wet precipitation of Cuiabá, Brazil [BibTeX] |
2012 | Atmospheric Research Vol. 107, pp. 9-19 |
article | |
BibTeX:
@article{dias_spatio-temporal_2012, author = {Dias, V. R. M. and Sanches, L. and Alves, M.C. and Nogueira, J.S.}, title = {Spatio-temporal variability of anions in wet precipitation of Cuiabá, Brazil}, journal = {Atmospheric Research}, year = {2012}, volume = {107}, pages = {9--19} } |
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Dias, N., Dias-Júnior, C., Mortarini, L., Acevedo, O., Oliveira, P., V Brondani, D., de Araújo, A., Rossato, F., Sörgel, M., Tsokankunku, A., Quesada, C., Oliveira, L., Teixeira, P.R., Takeshi, B., Mata, J., Xavier, T. and Manzi, A. | A Comparison Experiment for the Amazon Tall Tower Observatory (Atto) Sonic Anemometers [BibTeX] |
1 | SSRN Electronic Journal | article | DOI |
BibTeX:
@article{dias_comparison_1, author = {Dias, Nelson and Dias-Júnior, Cléo and Mortarini, Luca and Acevedo, Otavio and Oliveira, Pablo and V Brondani, Daiane and de Araújo, Alessandro and Rossato, Fernando and Sörgel, M. and Tsokankunku, Anywhere and Quesada, Carlos and Oliveira, Leonardo and Teixeira, Paulo Ricardo and Takeshi, Bruno and Mata, Jailson and Xavier, Thiago and Manzi, Antonio}, title = {A Comparison Experiment for the Amazon Tall Tower Observatory (Atto) Sonic Anemometers}, journal = {SSRN Electronic Journal}, year = {1}, doi = {https://doi.org/10.2139/ssrn.4371090} } |
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Dias, L., Macedo, M., Costa, M., Coe, M. and Neill, C. | Effects of land cover change on evapotranspiration and streamflow of small catchments in the Upper Xingu River Basin, Central Brazil [BibTeX] |
2015 | Journal of Hydrology: Regional Studies Vol. 4, pp. 108-122 |
article | |
BibTeX:
@article{dias_effects_2015, author = {Dias, L.C.P. and Macedo, M.N. and Costa, M.H. and Coe, M.T. and Neill, C.}, title = {Effects of land cover change on evapotranspiration and streamflow of small catchments in the Upper Xingu River Basin, Central Brazil}, journal = {Journal of Hydrology: Regional Studies}, year = {2015}, volume = {4}, pages = {108--122} } |
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Dias Junior, C., Sa´, L., Pachêco, V. and Souza, C.d. | Coherent structures detected in the unstable atmospheric surface layer above the Amazon forest [BibTeX] |
2013 | Journal Wind Eng. Ind. Aerodyn. Vol. 115, pp. 1-8 |
article | |
BibTeX:
@article{dias_junior_coherent_2013, author = {Dias Junior, C.Q. and Sa´, L.D.A. and Pachêco, V.B. and Souza, C.M. de}, title = {Coherent structures detected in the unstable atmospheric surface layer above the Amazon forest}, journal = {Journal Wind Eng. Ind. Aerodyn.}, year = {2013}, volume = {115}, pages = {1--8} } |
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Dias Jr., C.Q., Sá, L.D.A., Marques Filho, E.P., Manzi, A.O., Trebs, I. and Winderlich, J. | Variabilidade vertical de estruturas coerentes na camada limite convectiva da Amazônia [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 112 - 114 |
article | |
BibTeX:
@article{dias_jr_variabilidade_2013, author = {Dias Jr., Cléo Q. and Sá, Leonardo D. A. and Marques Filho, Edson P. and Manzi, Antonio O. and Trebs, Ivonne and Winderlich, Jan}, title = {Variabilidade vertical de estruturas coerentes na camada limite convectiva da Amazônia}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {112 -- 114} } |
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Dias Jr., C.Q., Sa, L. and Marques Filho, E. | Detecção de estruturas coerentes no escoamento turbulento acima da FLONA de Caxiuanã durante o Experimento COBRA-PARÁ [BibTeX] |
2007 | Revista Ciência e Natura, pp. 157-160 | article | |
BibTeX:
@article{dias_jr_deteccao_2007, author = {Dias Jr., C. Q. and Sa, L.D.A. and Marques Filho, E.P.}, title = {Detecção de estruturas coerentes no escoamento turbulento acima da FLONA de Caxiuanã durante o Experimento COBRA-PARÁ}, journal = {Revista Ciência e Natura}, year = {2007}, pages = {157--160} } |
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Dias, J.L., da Costa, A.C.L. and Oliveira, A.B... | Variabilidade do fluxo de C)2 no solo em duas parcelas experimentais do projeto ESECAFLOR/CAXIUANÃ - PA [BibTeX] |
2018 | CIÊNCIA E NATURA Vol. 40, pp. 144 |
article | |
BibTeX:
@article{dias_variabilidade_2018, author = {Dias, J. L. and da Costa, A. C. L. and Oliveira, A. B. .}, title = {Variabilidade do fluxo de C)2 no solo em duas parcelas experimentais do projeto ESECAFLOR/CAXIUANÃ - PA}, journal = {CIÊNCIA E NATURA}, year = {2018}, volume = {40}, pages = {144} } |
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Denich, M., Vlek, P.L.G., Sa, T.D.D., Vielhauer, K. and Lucke, W.G. | A concept for the development of fire-free fallow management in the Eastern Amazon, Brazil | 2005 | Agriculture Ecosystems & Environment Vol. 110(1-2), pp. 43-58 |
article | DOI URL |
Abstract: Research-based improvements in small-farmer land-use systems are difficult to bring about. Often such improvements developed under research station conditions fail to address the true system problems or farmer concerns. In the search for ways to improve the traditional fallow system of the Eastern Amazon, field experiments were conducted in farmers' fields, but under researcher management with farmers helping to identify the critical needs for improvement. To achieve the objective a phased plan was followed: (1) exploratory research, (2) solution-oriented research with technology development and prototype evaluation, and (3) implementation-oriented research. The initial exploratory or diagnostic studies focused on (1) biomass accumulation, (2) nutrient dynamics and (3) fallow regeneration. It was found that (1) the live and dead above-ground biomass of 1-10-year-old fallow vegetation amounts to 10-98 Mg ha(-1), (2) in the nutrient balance of a crop/fallow cycle including slash burning and fertilization nutrient losses exceed inputs for N, K, Ca and Mg, but not for P, and (3) vegetative resprouting of trees/shrubs exceeds in importance their regeneration by seeds and mechanized land preparation halves the accumulation of woody biomass of a 2-year-old fallow vegetation, compared to no tillage. Instead of designing an entirely new land-use system, modifications were studied only to those practices and components recognized to be harmful to the sustainability of the traditional system itself. Also, additional components to further improve the system were tested. Thus, various technologies were developed as a set of modules. These include: (1) mulch technology, (2) fire-free land clearing with a newly developed tractor-driven bush chopper to transform fallow vegetation into mulch, (3) enrichment planting with Acacia auriculiformis to accumulate twice as much biomass within 2 years as not managed fallows, (4) modification of the cropping period by doubling it, by shifting the planting date, and by re-arranging the crop sequence, and (5) the test of modern low-input crop varieties: rice and cassava cultivars were identified for the mulch-based system which yield higher than locally widespread ones. Adoption of these modules is flexible, leaving the farmer in control of the innovation process. This last phase of implementation-oriented research, currently underway, is participatory and multidisciplinary in nature and seeks to develop and assess implementation strategies aimed at the diffusion of the farming system improvements. (c) 2005 Published by Elsevier B.V. | |||||
BibTeX:
@article{denich_concept_2005, author = {Denich, M. and Vlek, P. L. G. and Sa, T. D. D. and Vielhauer, K. and Lucke, W. G.}, title = {A concept for the development of fire-free fallow management in the Eastern Amazon, Brazil}, journal = {Agriculture Ecosystems & Environment}, year = {2005}, volume = {110}, number = {1-2}, pages = {43--58}, url = {://WOS:000231409400004}, doi = {https://doi.org/10.1016/j.agee.2005.05.005} } |
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Delire, C., Levis, S., Bonan, G., Foley, J.A., Coe, M. and Vavrus, S. | Comparison of the climate simulated by the CCM3 coupled to two different land-surface models | 2002 | Climate Dynamics Vol. 19(8), pp. 657-669 |
article | URL |
Abstract: We present results from a coupled atmosphere-biosphere model CCM3/IBIS (the Community Climate Model coupled to the Integrated BIosphere Simulator), which is designed to study the dynamic interactions between climate and vegetation and the global carbon cycle. We analyze the climate simulated by CCM3/IBIS with fixed vegetation conditions and we compare it to the climate simulated by the standard CCM3, which includes the LSM (land surface model) land-surface package. Important differences between the two models include simple parametrizations of lakes, wetlands and crops in CCM3/LSM not taken into account in CCM3/IBIS. CCM3/IBIS and CCM3/LSM share common biases (compared to observations) in the temperature field in boreal winter and in the precipitation field annually, making the atmospheric model the most probable cause of those biases. The models differ in the temperature field and surface energy balance in the Sahara annually and in the mid-to high latitudes from spring through fall. CCM3/IBIS simulates global annual air temperatures that are on average 1.7 degreesC higher than CCM3/LSM and 0.5 degreesC higher than the observed climatology. Differences in albedo and/or snow parametrization explain most of the Sahara and high-latitude temperature disagreement. Our sensitivity study with CCM3/LSM shows that the presence of lakes and wetlands in CCM3/LSM can account for about half of the difference in temperature in summer over the lake and wetland regions of the mid-latitudes. A second sensitivity study shows that higher surface roughness length in CCM3/IBIS can also explain part of the difference in summer surface temperature in the mid-latitudes. Surface roughness length affects the surface temperature through a feedback mechanism linking surface wind speed, planetary boundary layer height, low level cloudiness and radiation. | |||||
BibTeX:
@article{delire_comparison_2002, author = {Delire, C. and Levis, S. and Bonan, G. and Foley, J. A. and Coe, M. and Vavrus, S.}, title = {Comparison of the climate simulated by the CCM3 coupled to two different land-surface models}, journal = {Climate Dynamics}, year = {2002}, volume = {19}, number = {8}, pages = {657--669}, url = {://WOS:000178993700003} } |
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Delire, C., Foley, J.A. and Thompson, S. | Evaluating the carbon cycle of a coupled atmosphere-biosphere model | 2003 | Global Biogeochemical Cycles Vol. 17(1) |
article | DOI URL |
Abstract: [1] We investigate how well a coupled biosphere-atmosphere model, CCM3-IBIS, can simulate the functioning of the terrestrial biosphere and the carbon cycling through it. The simulated climate is compared to observations, while the vegetation cover and the carbon cycle are compared to an off-line version of the biosphere model IBIS forced with observed climatic variables. The simulated climate presents some local biases that strongly affect the vegetation (e.g., a misrepresentation of the African monsoon). Compared to the off-line model, the coupled model simulates well the globally averaged carbon fluxes and vegetation pools. The zonal mean carbon fluxes and the zonal mean seasonal cycle are also well represented except between 0degrees and 20degreesN due to the misrepresentation of the African monsoon. These results suggest that, despite regional biases in climate and ecosystem simulations, this coupled atmosphere-biosphere model can be used to explore geographic and temporal variations in the global carbon cycle. | |||||
BibTeX:
@article{delire_evaluating_2003, author = {Delire, C. and Foley, J. A. and Thompson, S.}, title = {Evaluating the carbon cycle of a coupled atmosphere-biosphere model}, journal = {Global Biogeochemical Cycles}, year = {2003}, volume = {17}, number = {1}, url = {://WOS:000181823000002}, doi = {https://doi.org/10.1029/2002gb001870} } |
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Delire, C. and Foley, J.A. | Evaluating the performance of a land Surface/ecosystem model with biophysical measurements from contrasting environments | 1999 | Journal of Geophysical Research-Atmospheres Vol. 104(D14), pp. 16895-16909 |
article | DOI URL |
Abstract: Five sets of biophysical and hydrological measurements from across the globe are used to test the performance of the Integrated Biosphere Simulator (IBIS) [Foley et al., 1996] in reproducing short-term and long-term evolution of soil moisture and temperature, surface energy fluxes and CO2 fluxes. The sites include a soybean crop in southwestern France (HAPEX-MOBILHY, 1986), a meadow in the Netherlands (Cabauw, 1987), a grassland in Russia (Valday-Usadievskiy, 1966-1983), a prairie in Kansas (FIFE, site 16, 1987-1989), and a tropical forest in Brazil (ABRACOS, Reserva Jaru, 1992-1993). IBIS adequately reproduces the evolution of the soil moisture together with the surface fluxes for those five different sites while only imposing a small number of site specific parameters describing vegetation characteristics and soil texture. The quality of the simulations is improved when detailed information regarding soil texture, rooting profiles, and leaf area index are available. | |||||
BibTeX:
@article{delire_evaluating_1999, author = {Delire, C. and Foley, J. A.}, title = {Evaluating the performance of a land Surface/ecosystem model with biophysical measurements from contrasting environments}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1999}, volume = {104}, number = {D14}, pages = {16895--16909}, url = {://WOS:000081652100020}, doi = {https://doi.org/10.1029/1999jd900212} } |
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Delbart, N., Ciais, P., Chave, J., Viovy, N., Malhi, Y. and Le Toan, T. | Mortality as a key driver of the spatial distribution of aboveground biomass in Amazonian forest: results from a dynamic vegetation model | 2010 | Biogeosciences Vol. 7(10), pp. 3027-3039 |
article | DOI URL |
Abstract: Dynamic Vegetation Models (DVMs) simulate energy, water and carbon fluxes between the ecosystem and the atmosphere, between the vegetation and the soil, and between plant organs. They also estimate the potential biomass of a forest in equilibrium having grown under a given climate and atmospheric CO(2) level. In this study, we evaluate the Above Ground Woody Biomass (AGWB) and the above ground woody Net Primary Productivity (NPP(AGW)) simulated by the DVM ORCHIDEE across Amazonian forests, by comparing the simulation results to a large set of ground measurements (220 sites for biomass, 104 sites for NPPAGW). We found that the NPPAGW is on average overestimated by 63%. We also found that the fraction of biomass that is lost through mortality is 85% too high. These model biases nearly compensate each other to give an average simulated AGWB close to the ground measurement average. Nevertheless, the simulated AGWB spatial distribution differs significantly from the observations. Then, we analyse the discrepancies in biomass with regards to discrepancies in NPPAGW and those in the rate of mortality. When we correct for the error in NPPAGW, the errors on the spatial variations in AGWB are exacerbated, showing clearly that a large part of the misrepresentation of biomass comes from a wrong modelling of mortality processes. Previous studies showed that Amazonian forests with high productivity have a higher mortality rate than forests with lower productivity. We introduce this relationship, which results in strongly improved modelling of biomass and of its spatial variations. We discuss the possibility of modifying the mortality modelling in ORCHIDEE, and the opportunity to improve forest productivity modelling through the integration of biomass measurements, in particular from remote sensing. | |||||
BibTeX:
@article{delbart_mortality_2010, author = {Delbart, N. and Ciais, P. and Chave, J. and Viovy, N. and Malhi, Y. and Le Toan, T.}, title = {Mortality as a key driver of the spatial distribution of aboveground biomass in Amazonian forest: results from a dynamic vegetation model}, journal = {Biogeosciences}, year = {2010}, volume = {7}, number = {10}, pages = {3027--3039}, url = {://WOS:000283659200005}, doi = {https://doi.org/10.5194/bg-7-3027-2010} } |
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Dehaini, J., Costa, J.d.S., Silva, M.L.d., Brito, A.P.d. and Ferreira, S.J.F. | Potentiometric map based on integrated piezometer data with geophysical results, Manaus-AM [BibTeX] |
2022 | Brazilian Journal of Development Vol. 8(4), pp. 32242-32252 |
article | DOI |
BibTeX:
@article{dehaini_potentiometric_2022, author = {Dehaini, Jamile and Costa, Josué da Silva and Silva, Márcio Luiz da and Brito, Alderlene Pimentel de and Ferreira, Sávio José Filgueiras}, title = {Potentiometric map based on integrated piezometer data with geophysical results, Manaus-AM}, journal = {Brazilian Journal of Development}, year = {2022}, volume = {8}, number = {4}, pages = {32242--32252}, doi = {https://doi.org/10.34117/bjdv8n4-622} } |
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DeFries, R.S., Morton, D.C., van der Werf, G.R., Giglio, L., Collatz, G.J., Randerson, J.T., Houghton, R.A., Kasibhatla, P.K. and Shimabukuro, Y. | Fire-related carbon emissions from land use transitions in southern Amazonia | 2008 | Geophysical Research Letters Vol. 35(22) |
article | DOI URL |
Abstract: Various land-use transitions in the tropics contribute to atmospheric carbon emissions, including forest conversion for small-scale farming, cattle ranching, and production of commodities such as soya and palm oil. These transitions involve fire as an effective and inexpensive means for clearing. We applied the DECAF (DEforestation CArbon Fluxes) model to Mato Grosso, Brazil to estimate fire emissions from various land-use transitions during 2001-2005. Fires associated with deforestation contributed 67 Tg C/yr (17 and 50 Tg C/yr from conversion to cropland and pasture, respectively), while conversion of savannas and existing cattle pasture to cropland contributed 17 Tg C/yr and pasture maintenance fires 6 Tg C/yr. Large clearings (textgreater100 ha/yr) contributed 67% of emissions but comprised only 10% of deforestation events. From a policy perspective, results imply that intensification of agricultural production on already-cleared land and policies to discourage large clearings would reduce the major sources of emissions from fires in this region. Citation: DeFries, R. S., D. C. Morton, G. R. van der Werf, L. Giglio, G. J. Collatz, J. T. Randerson, R. A. Houghton, P. K. Kasibhatla, and Y. Shimabukuro (2008), Fire-related carbon emissions from land use transitions in southern Amazonia, Geophys. Res. Lett., 35, L22705, doi:10.1029/2008GL035689. | |||||
BibTeX:
@article{defries_fire-related_2008, author = {DeFries, R. S. and Morton, D. C. and van der Werf, G. R. and Giglio, L. and Collatz, G. J. and Randerson, J. T. and Houghton, R. A. and Kasibhatla, P. K. and Shimabukuro, Y.}, title = {Fire-related carbon emissions from land use transitions in southern Amazonia}, journal = {Geophysical Research Letters}, year = {2008}, volume = {35}, number = {22}, url = {://WOS:000261244000002}, doi = {https://doi.org/10.1029/2008gl035689} } |
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DeFries, R.S., Foley, J.A. and Asner, G.P. | Land-use choices: balancing human needs and ecosystem function | 2004 | Frontiers in Ecology and the Environment Vol. 2(5), pp. 249-257 |
article | DOI URL |
Abstract: Conversion of land to grow crops, raise animals, obtain timber, and build cities is one of the foundations of human civilization. While land use provides these essential ecosystem goods, it alters a range of other ecosystem functions, such as the provisioning of freshwater, regulation of climate and biogeochemical cycles, and maintenance of soil fertility. It also alters habitat for biological diversity. Balancing the inherent trade-offs between satisfying immediate human needs and maintaining other ecosystem functions requires quantitative knowledge about ecosystem responses to land use. These responses vary according to the type of land-use change and the ecological setting, and have local, short-term as well as global, long-term effects. Land-use decisions ultimately weigh the need to satisfy human demands and the unintended ecosystem responses based on societal values, but ecological knowledge can provide a basis for assessing the trade-offs. | |||||
BibTeX:
@article{defries_land-use_2004, author = {DeFries, R. S. and Foley, J. A. and Asner, G. P.}, title = {Land-use choices: balancing human needs and ecosystem function}, journal = {Frontiers in Ecology and the Environment}, year = {2004}, volume = {2}, number = {5}, pages = {249--257}, url = {://WOS:000223960800016}, doi = {https://doi.org/10.2307/3868265} } |
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DeFries, R., Asner, G.P. and Foley, J. | A glimpse out the window: Landscapes, livelihoods, and the environment | 2006 | Environment Vol. 48(8), pp. 22-36 |
article | DOI URL |
Abstract: Throughout human history, civilizations have planted crops, reared animals, developed complex irrigation schemes, built cities, and devised technologies to make life more comfortable and less vulnerable to the vagaries of drought, floods, and other potentially catastrophic events. | |||||
BibTeX:
@article{defries_glimpse_2006, author = {DeFries, Ruth and Asner, Gregory P. and Foley, Jonathan}, title = {A glimpse out the window: Landscapes, livelihoods, and the environment}, journal = {Environment}, year = {2006}, volume = {48}, number = {8}, pages = {22--36}, url = {://WOS:000241790200004}, doi = {https://doi.org/10.3200/envt.48.8.22-36} } |
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DeFries, R., Achard, F., Brown, S., Herold, M., Murdiyarso, D., Schlamadinger, B. and de Souza Jr., C. | Earth observations for estimating greenhouse gas emissions from deforestation in developing countries | 2007 | Environmental Science & Policy Vol. 10(4), pp. 385-394 |
article | DOI URL |
Abstract: In response to the United Nations Framework Convention on Climate Change (UNFCCC) process investigating the technical issues surrounding the ability to reduce greenhouse gas (GHG) emissions from deforestation in developing countries, this paper reviews technical capabilities for monitoring deforestation and estimating emissions. Implementation of policies to reduce emissions from deforestation require effective deforestation monitoring systems that are reproducible, provide consistent results, meet standards for mapping accuracy, and can be implemented at the national level. Remotely sensed data supported by ground observations are key to effective monitoring. Capacity in developing countries for deforestation monitoring is well-advanced in a few countries and is a feasible goal in most others. Data sources exist to determine base periods in the 1990s as historical reference points. Forest degradation (e.g. from high impact logging and fragmentation) also contribute to greenhouse gas emissions but it is more technically challenging to measure than deforestation. Data on carbon stocks, which are needed to estimate emissions, cannot currently be observed directly over large areas with remote sensing. Guidelines for carbon accounting from deforestation exist and are available in approved Intergovernmental Panel on Climate Change (IPCC) reports and can be applied at national scales in the absence of forest inventory or other data. Key constraints for implementing programs to monitor greenhouse gas emissions from deforestation are international commitment of resources to increase capacity, coordination of observations to ensure pan-tropical coverage, access to free or low-cost data, and standard and consensual protocols for data interpretation and analysis. (c) 2007 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{defries_earth_2007, author = {DeFries, Ruth and Achard, Frederic and Brown, Sandra and Herold, Martin and Murdiyarso, Daniel and Schlamadinger, Bernhard and de Souza, Jr., Carlos}, title = {Earth observations for estimating greenhouse gas emissions from deforestation in developing countries}, journal = {Environmental Science & Policy}, year = {2007}, volume = {10}, number = {4}, pages = {385--394}, url = {://WOS:000247823900010}, doi = {https://doi.org/10.1016/j.envsci.2007.01.010} } |
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Deeter, M.N., Martínez-Alonso, S., Andreae, M.O. and Schlager, H. | Satellite-Based Analysis of CO Seasonal and Interannual Variability Over the Amazon Basin [BibTeX] |
2018 | Journal of GeophysicalResearch: Atmospheres Vol. 123 |
article | DOI |
BibTeX:
@article{deeter_satellite-based_2018, author = {Deeter, M. N. and Martínez-Alonso, S. and Andreae, Meinrat O. and Schlager, H.}, title = {Satellite-Based Analysis of CO Seasonal and Interannual Variability Over the Amazon Basin}, journal = {Journal of GeophysicalResearch: Atmospheres}, year = {2018}, volume = {123}, doi = {https://doi.org/10.1029/2018JD028425} } |
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Deegan, L.A., Neill, C., Haupert, C.L., Ballester, M.V.R., Krusche, A.V., Victoria, R.L., Thomas, S.M. and de Moor, E. | Amazon deforestation alters small stream structure, nitrogen biogeochemistry and connectivity to larger rivers | 2011 | Biogeochemistry Vol. 105(1-3), pp. 53-74 |
article | DOI URL |
Abstract: Human activities that modify land cover can alter the structure and biogeochemistry of small streams but these effects are poorly known over large regions of the humid tropics where rates of forest clearing are high. We examined how conversion of Amazon lowland tropical forest to cattle pasture influenced the physical and chemical structure, organic matter stocks and N cycling of small streams. We combined a regional ground survey of small streams with an intensive study of nutrient cycling using (15)N additions in three representative streams: a second-order forest stream, a second-order pasture stream and a third-order pasture stream. These three streams were within several km of each other and on similar soils. Replacement of forest with pasture decreased stream habitat complexity by changing streams from run and pool channels with forest leaf detritus (50% cover) to grass-filled (63% cover) channel with runs of slow-moving water. In the survey, pasture streams consistently had lower concentrations of dissolved oxygen and nitrate (NO(3) (-)) compared with similar-sized forest streams. Stable isotope additions revealed that second-order pasture stream had a shorter NH(4) (+) uptake length, higher uptake rates into organic matter components and a shorter (15)NH(4) (+) residence time than the second-order forest stream or the third-order pasture stream. Nitrification was significant in the forest stream (19% of the added (15)NH(4) (+)) but not in the second-order pasture (0%) or third-order (6%) pasture stream. The forest stream retained 7% of added (15)N in organic matter compartments and exported 53% ((15)NH(4) (+) = 34%; (15)NO(3) (-) = 19%). In contrast, the second-order pasture stream retained 75% of added (15)N, predominantly in grasses (69%) and exported only 4% as (15)NH(4) (+). The fate of tracer (15)N in the third-order pasture stream more closely resembled that in the forest stream, with 5% of added N retained and 26% exported ((15)NH(4) (+) = 9%; (15)NO(3) (-) = 6%). These findings indicate that the widespread infilling by grass in small streams in areas deforested for pasture greatly increases the retention of inorganic N in the first- and second-order streams, which make up roughly three-fourths of total stream channel length in Amazon basin watersheds. The importance of this phenomenon and its effect on N transport to larger rivers across the larger areas of the Amazon Basin will depend on better evaluation of both the extent and the scale at which stream infilling by grass occurs, but our analysis suggests the phenomenon is widespread. | |||||
BibTeX:
@article{deegan_amazon_2011, author = {Deegan, Linda A. and Neill, Christopher and Haupert, Christie L. and Ballester, M. Victoria R. and Krusche, Alex V. and Victoria, Reynaldo L. and Thomas, Suzanne M. and de Moor, Emily}, title = {Amazon deforestation alters small stream structure, nitrogen biogeochemistry and connectivity to larger rivers}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {53--74}, url = {://WOS:000294501100005 http://www.springerlink.com/content/n704547m12556v08/fulltext.pdf}, doi = {https://doi.org/10.1007/s10533-010-9540-4} } |
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Decesari, S., Fuzzi, S., Facchini, M.C., Mircea, M., Emblico, L., Cavalli, F., Maenhaut, W., Chi, X., Schkolnik, G., Falkovich, A., Rudich, Y., Claeys, M., Pashynska, V., Vas, G., Kourtchev, I., Vermeylen, R., Hoffer, A., Andreae, M.O., Tagliavini, E., Moretti, F. and Artaxo, P. | Characterization of the organic composition of aerosols from Rondonia, Brazil, during the LBA-SMOCC 2002 experiment and its representation through model compounds | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 375-402 |
article | URL |
Abstract: The chemical composition of carbonaceous aerosols collected during the LBA-SMOCC field experiment, conducted in Rondonia, Brazil, in 2002 during the transition from the dry to the wet season, was investigated by a suite of state-of-the-art analytical techniques. The period of most intense biomass burning was characterized by high concentrations of submicron particles rich in carbonaceous material and water-soluble organic compounds (WSOC). At the onset of the rainy period, submicron total carbon (TC) concentrations decreased by about 20 times. In contrast, the concentration of supermicron TC was fairly constant throughout the experiment, pointing to a constant emission of coarse particles from the natural background. About 6 - 8% of TC ( 9 - 11% of WSOC) was speciated at the molecular level by GC-MS and liquid chromatography. Polyhydroxylated compounds, aliphatic and aromatic acids were the main classes of compounds accounted for by individual compound analysis. Functional group analysis by proton NMR and chromatographic separation on ion-exchange columns allowed characterization of ca. 50 - 90% of WSOC into broad chemical classes (neutral species/light acids/humic-like substances). In spite of the significant change in the chemical composition of tracer compounds from the dry to the wet period, the functional groups and the general chemical classes of WSOC changed only to a small extent. Model compounds representing size-resolved WSOC chemical composition for the different periods of the campaign are then proposed in this paper, based on the chemical characterization by both individual compound analysis and functional group analysis deployed during the LBA-SMOCC experiment. Model compounds reproduce quantitatively the average chemical structure of WSOC and can be used as best-guess surrogates in microphysical models involving organic aerosol particles over tropical areas affected by biomass burning. | |||||
BibTeX:
@article{decesari_characterization_2006, author = {Decesari, S. and Fuzzi, S. and Facchini, M. C. and Mircea, M. and Emblico, L. and Cavalli, F. and Maenhaut, W. and Chi, X. and Schkolnik, G. and Falkovich, A. and Rudich, Y. and Claeys, M. and Pashynska, V. and Vas, G. and Kourtchev, I. and Vermeylen, R. and Hoffer, A. and Andreae, M. O. and Tagliavini, E. and Moretti, F. and Artaxo, P.}, title = {Characterization of the organic composition of aerosols from Rondonia, Brazil, during the LBA-SMOCC 2002 experiment and its representation through model compounds}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {375--402}, url = {://WOS:000235179600001} } |
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Decesari, S., Facchini, M.C., Fuzzi, S. and Tagliavini, E. | Characterization of water-soluble organic compounds in atmospheric aerosol: A new approach | 2000 | Journal of Geophysical Research-Atmospheres Vol. 105(D1), pp. 1481-1489 |
article | DOI URL |
Abstract: A new methodological approach is proposed to characterize aerosol water-soluble organic compounds (WSOC). Real aerosol and fog water samples were subjected to a procedure based on a combination of chromatographic separations, functional group investigation by proton nuclear magnetic resonance (HNMR), and total organic carbon determination. The complex mixture of aerosol/fog WSOC was separated by a chromatographic procedure into three main classes of compounds: (1) neutral/basic compounds; (2) mono- and di-carboxylic acids; (3) polyacidic compounds. Characterization by HNMR spectroscopy showed that fraction 1 is mainly composed of polyols or polyethers, fraction 2 is mainly composed of hydroxylated aliphatic acidic compounds, while fraction 3 is composed of highly unsaturated polyacidic compounds of predominantly aliphatic character, with a minor content of hydroxyl- groups. Quantitative data on the three classes of compounds were then derived from total organic carbon analysis, showing that the three separated fractions together account for 77% (in terms of C) of the total WSOC concentration of a fog water sample. Further quantitative information on the functional groups present in the three separated fractions can be obtained from HNMR spectra. This newly proposed approach to aerosol WSOC characterization provides comprehensive and synthetic information on aerosol organic composition which can be helpful for modeling purposes and is also particularly useful when aerosol chemical mass closure is pursued. | |||||
BibTeX:
@article{decesari_characterization_2000, author = {Decesari, S. and Facchini, M. C. and Fuzzi, S. and Tagliavini, E.}, title = {Characterization of water-soluble organic compounds in atmospheric aerosol: A new approach}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2000}, volume = {105}, number = {D1}, pages = {1481--1489}, url = {://WOS:000084856600014 http://www.agu.org/journals/jd/v105/iD01/1999JD900950/1999JD900950.pdf}, doi = {https://doi.org/10.1029/1999jd900950} } |
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DeArmond, D., Ferraz, J.B.S., Marra, D.M., Amaral, M.R.M., Lima, A.J.N. and Higuchi, N. | Logging intensity affects growth and lifespan trajectories for pioneer species in Central Amazonia | 2022 | Forest Ecology and Management Vol. 522, pp. 120450 |
article | DOI URL |
Abstract: Management of tropical forest in the form of timber harvesting is a viable alternative to deforestation in Amazonia. Nevertheless, a significant challenge for timber management in the Amazon is the maintenance or establishment of commercial timber species, after logging operations are completed. This is because fast-growing non-commercial pioneer species outcompete the slower growing timber species. To determine the challenges posed to commercial species in the context of the cutting cycle in the Brazilian Amazon of 25–35 years, growth and cumulative survival rates of six abundant pioneer species were assessed. This was accomplished with 30 years of growth data from permanent plots established in the Central Amazon in the 1980′s and logged in 1987 and 1988 at various intensities. In terms of relative growth rates, pioneer species dominated the post-logging site by 2 to 5 times, when compared to commercial species, throughout the evaluation period. This was regardless of the various logging intensities of 5, 8 or 16 trees harvested per hectare. Two commercial pioneer species, Jacaranda copaia and Simarouba amara, presented rapid growth rates similar to non-commercial pioneer species. Three pioneer species survived beyond 30 years to continue into a potential 2nd cutting cycle. Therefore, to maintain or establish commercial timber species while there is a continued and expanding site occupancy of non-commercial pioneer species after logging presents numerous challenges for sustainable forest management. | |||||
BibTeX:
@article{dearmond_logging_2022, author = {DeArmond, Daniel and Ferraz, João B. S. and Marra, Daniel M. and Amaral, Márcio R. M. and Lima, Adriano J. N. and Higuchi, Niro}, title = {Logging intensity affects growth and lifespan trajectories for pioneer species in Central Amazonia}, journal = {Forest Ecology and Management}, year = {2022}, volume = {522}, pages = {120450}, url = {https://www.sciencedirect.com/science/article/pii/S0378112722004443}, doi = {https://doi.org/10.1016/j.foreco.2022.120450} } |
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de Souza, M., Rocha, R.P.d., Ambrizzi, T. and Vidale, P.L. | Avaliação da climatologia na região Amazônica nos modelos da família HiGEM [BibTeX] |
2016 | Ciência e Natura Vol. 38(2), pp. 10554-1063 |
article | |
BibTeX:
@article{de_souza_avaliacao_2016, author = {de Souza, M.C. and Rocha, R. P. da and Ambrizzi, T. and Vidale, P. L.}, title = {Avaliação da climatologia na região Amazônica nos modelos da família HiGEM}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, number = {2}, pages = {10554--1063} } |
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de Souza Custodio, M., da Rocha, R.P., Ambrizzi, T., Vidale, P.L. and Demory, M.-E. | Impact of increased horizontal resolution in coupled and atmosphere-only models of the HadGEM1 family upon the climate patterns of South America [BibTeX] |
2016 | Climate Dynamics, pp. 1-24 | article | DOI |
BibTeX:
@article{de_souza_custodio_impact_2016, author = {de Souza Custodio, M. and da Rocha, R. P. and Ambrizzi, T. and Vidale, P. L. and Demory, M.-E.}, title = {Impact of increased horizontal resolution in coupled and atmosphere-only models of the HadGEM1 family upon the climate patterns of South America}, journal = {Climate Dynamics}, year = {2016}, pages = {1--24}, doi = {https://doi.org/10.1007/s00382-016-3271-8} } |
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de Sá, S.S., Palm, B.B., Campuzano-Jost, P., Day, D.A., Hu, W., Isaacman-VanWertz, G., Yee, L.D., Brito, J., Carbone, S., Ribeiro, I.O., Cirino, G.G., Liu, Y., Thalman, R., Sedlacek, A., Funk, A., Schumacher, C., Shilling, J.E., Schneider, J., Artaxo, P., Goldstein, A.H., Souza, R.A.F., Wang, J., McKinney, K.A., Barbosa, H., Alexander, M.L., Jimenez, J.L. and Martin, S.T. | Urban influence on the concentration and composition of submicron particulate matter in central Amazonia [BibTeX] |
2018 | Atmos. Chem. Phys. Vol. 18(16), pp. 12185-12206 |
article | DOI URL |
BibTeX:
@article{de_sa_urban_2018, author = {de Sá, S. S. and Palm, B. B. and Campuzano-Jost, P. and Day, D. A. and Hu, W. and Isaacman-VanWertz, G. and Yee, L. D. and Brito, J. and Carbone, S. and Ribeiro, I. O. and Cirino, G. G. and Liu, Y. and Thalman, R. and Sedlacek, A. and Funk, A. and Schumacher, C. and Shilling, J. E. and Schneider, J. and Artaxo, P. and Goldstein, A. H. and Souza, R. A. F. and Wang, J. and McKinney, K. A. and Barbosa, H. and Alexander, M. L. and Jimenez, J. L. and Martin, S. T.}, title = {Urban influence on the concentration and composition of submicron particulate matter in central Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2018}, volume = {18}, number = {16}, pages = {12185--12206}, url = {https://acp.copernicus.org/articles/18/12185/2018/}, doi = {https://doi.org/10.5194/acp-18-12185-2018} } |
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de Sá Rizzo, L.V.P.B.B.C.-J.P.D.D.A.Y.L.D.W.R.I.-V.G.B.J.C.S.L.Y.J.S.A.S.S.G.A.H.B.H.M.J.A.M.L.A.P.J.J.L.and.M.S.T.S.S. | Contributions of biomass-burning, urban, and biogenic emissions to the concentrations and light-absorbing properties of particulate matter in central Amazonia during the dry season [BibTeX] |
2019 | Atmos. Chem. Phys. Vol. 19, pp. 7973-8001 |
article | DOI |
BibTeX:
@article{de_sa_contributions_2019, author = {de Sá, Rizzo, L. V., Palm, B. B., Campuzano-Jost, P., Day, D. A., Yee, L. D., Wernis, R., Isaacman-VanWertz, G., Brito, J., Carbone, S., Liu, Y. J., Sedlacek, A., Springston, S., Goldstein, A. H., Barbosa, H. M. J., Alexander, M. L., Artaxo, P., Jimenez, J. L., and Martin, S. T, S. S.}, title = {Contributions of biomass-burning, urban, and biogenic emissions to the concentrations and light-absorbing properties of particulate matter in central Amazonia during the dry season}, journal = {Atmos. Chem. Phys.}, year = {2019}, volume = {19}, pages = {7973--8001}, doi = {https://doi.org/10.5194/acp-19-7973-2019} } |
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de Oliveira, C.P., Ambrizzi, T. and Aimola, L. | Influence of intraseasonal variability on precipitation in northern South America during the winter season [BibTeX] |
2016 | International Journal of Climatology Vol. 45, pp. 1250-1264 |
article | |
BibTeX:
@article{de_oliveira_influence_2016, author = {de Oliveira, C. P. and Ambrizzi, T. and Aimola, L.}, title = {Influence of intraseasonal variability on precipitation in northern South America during the winter season}, journal = {International Journal of Climatology}, year = {2016}, volume = {45}, pages = {1250--1264} } |
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De Jesus Veiga, CM, Wittmann, M., Da Silva Guimarães, J., De Cássia L Tostes L., F. and Piedade | Composition, diversity, and structure of tidal Várzea and Igapó floodplain forests in eastern Amazonia, Brazil [BibTeX] |
2017 | Brazilian Journal of Botany Vol. 40(1), pp. 115-124 |
article | |
BibTeX:
@article{de_jesus_veiga_cm_wittmann_composition_2017, author = {De Jesus Veiga CM; Wittmann, MTF; Da Silva Guimarães, JR; De Cássia L Tostes, L., F; Piedade}, title = {Composition, diversity, and structure of tidal Várzea and Igapó floodplain forests in eastern Amazonia, Brazil}, journal = {Brazilian Journal of Botany}, year = {2017}, volume = {40}, number = {1}, pages = {115--124} } |
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De Freitas, G., Piedade MTF., C. and Shepard | The Floating Forest: Traditional Knowledge and Use of Matupá Vegetation Islands by Riverine Peoples of the Central Amazon [BibTeX] |
2015 | PLos ONE Vol. 10, pp. e0122542 |
article | |
BibTeX:
@article{de_freitas_floating_2015, author = {De Freitas, GH; Piedade, MTF., CT; Shepard}, title = {The Floating Forest: Traditional Knowledge and Use of Matupá Vegetation Islands by Riverine Peoples of the Central Amazon}, journal = {PLos ONE}, year = {2015}, volume = {10}, pages = {e0122542} } |
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De Faria, F.A.M., Jaramillo, P., Sawakuchi, H.O., Richey, J.E. and Barros, N. | Estimating greenhouse gas emissions from future Amazonian hydroelectric reservoirs [BibTeX] |
2015 | Environmental Research Letters Vol. 10, n. , DEC.(12) |
article | |
BibTeX:
@article{de_faria_estimating_2015, author = {De Faria, F. A. M. and Jaramillo, P. and Sawakuchi, Henrique O. and Richey, Jeffrey E. and Barros, N.}, title = {Estimating greenhouse gas emissions from future Amazonian hydroelectric reservoirs}, journal = {Environmental Research Letters}, year = {2015}, volume = {10, n. , DEC.}, number = {12} } |
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de Assis, R.L., Wittmann, F., Bredin, Y.K., Schöngart, J., Nobre Quesada, C.A., Piedade, M.T.F. and Haugaasen, T. | Above-ground woody biomass distribution in Amazonian floodplain forests: Effects of hydroperiod and substrate properties | 2019 | Forest Ecology and Management Vol. 432, pp. 365-375 |
article | DOI URL |
Abstract: The importance of tropical forests in regulating global carbon stocks is well known. However, the role of abiotic variables related to climate conditions and edaphic parameters for patterns of above-ground woody biomass (AGWB) are still under debate. For Amazonian forests subjected to periodic floods, these patterns are even more uncertain. This study aimed to evaluate AGWB stocks in Amazonian floodplain forest, and investigate the importance of forest structure, hydroperiod and edaphic parameters for AGWB. Results are based on floristic inventories conducted in twelve hectares of forest distributed across four floodplains. All trees ≥10 cm DBH were tagged, identified, and had their DBH and height measured. Allometric equations were applied for calculating AGWB. Hydroperiod was estimated for each sample plot, and soil samples were collected and chemical and physical components analyzed. Hierarchical partitioning was applied to determine importance of forest structure variables for AGWB, and GLMMs to evaluate the individual role of several edaphic parameters and hydroperiod for AGWB stocks. AGWB estimates varied substantially both between and within sites, as did the proportional contribution of forest structure variables to AGWB. Fabaceae contributed most to AGWB overall, and hydroperiod was more important than soil fertility in explaining variation in AGWB values. Amongst the edaphic variables, Iron (Fe) was the component that influenced AGWB the most, followed by Aluminium (Al) and Phosphorus (P). Overall, our results indicate that, on the investigated Amazonian floodplains, AGWB is mainly driven by hydroperiod rather than edaphic properties. This occurs despite a constant input of nutrients caused by flooding events. In addition, this is the first study to suggest that P appears to be of some importance in Amazonian várzea and paleo-várzea floodplains, where soil fertility is generally higher than in non-flooded terra firme forests. | |||||
BibTeX:
@article{de_assis_above-ground_2019, author = {de Assis, Rafael Leandro and Wittmann, Florian and Bredin, Yennie Katarina and Schöngart, Jochen and Nobre Quesada, Carlos Alberto and Piedade, Maria Teresa Fernandes and Haugaasen, Torbjørn}, title = {Above-ground woody biomass distribution in Amazonian floodplain forests: Effects of hydroperiod and substrate properties}, journal = {Forest Ecology and Management}, year = {2019}, volume = {432}, pages = {365--375}, url = {https://www.sciencedirect.com/science/article/pii/S0378112718313021}, doi = {https://doi.org/10.1016/j.foreco.2018.09.031} } |
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de Almeida Castanho, A.D., Coe, M.T., Heil Costa, M., Malhi, Y., Galbraith, D. and Quesada, C.A. | Accounting for spatial variation in vegetation properties improves simulations of Amazon forest biomass and productivity in a global vegetation model [BibTeX] |
2012 | Biogeosciences Discussion (Online) Vol. 9, pp. 11767-11813 |
article | |
BibTeX:
@article{de_almeida_castanho_accounting_2012, author = {de Almeida Castanho, A. D. and Coe, M. T. and Heil Costa, M. and Malhi, Y. and Galbraith, D. and Quesada, C. A.}, title = {Accounting for spatial variation in vegetation properties improves simulations of Amazon forest biomass and productivity in a global vegetation model}, journal = {Biogeosciences Discussion (Online)}, year = {2012}, volume = {9}, pages = {11767--11813} } |
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Davidson, E.A., Verchot, L.V., Cattanio, J.H., Ackerman, I.L. and Carvalho, J.E.M. | Effects of soil water content on soil respiration in forests and cattle pastures of eastern Amazonia | 2000 | Biogeochemistry Vol. 48(1), pp. 53-69 |
article | DOI URL |
Abstract: The effect of soil water content on efflux of CO2 from soils has been described by linear, logarithmic, quadratic, and parabolic functions of soil water expressed as matric potential, gravimetric and volumetric water content, water holding capacity, water-filled pore space, precipitation indices, and depth to water table. The effects of temperature and water content are often statistically confounded. The objectives of this study are: (1) to analyze seasonal variation in soil water content and soil respiration in the eastern Amazon Basin where seasonal temperature variation is minor; and (2) to examine differences in soil CO2 emissions among primary forests, secondary forests, active cattle pastures, and degraded cattle pastures. Rates of soil respiration decreased from wet to dry seasons in all land uses. Grasses in the active cattle pasture were productive in the wet season and senescent in the dry season, resulting in the largest seasonal amplitude of CO2 emissions, whereas deep-rooted forests maintained substantial soil respiration during the dry season. Annual emissions were 2.0, 1.8, 1.5, and 1.0 kg C m(-2) yr(-1) for primary forest, secondary forest, active pasture, and degraded pasture, respectively. Emissions of CO2 were correlated with the logarithm of matric potential and with the cube of volumetric water content, which are mechanistically appropriate functions for relating soil respiration at below-optimal water contents. The parameterization of these empirical functions was not consistent with those for a temperate forest. Relating rates of soil respiration to water and temperature measurements made at some arbitrarily chosen depth of the surface horizons is simplistic. Further progress in defining temperature and moisture functions may require measurements of temperature, water content and CO2 production for each soil horizon. | |||||
BibTeX:
@article{davidson_effects_2000, author = {Davidson, E. A. and Verchot, L. V. and Cattanio, J. H. and Ackerman, I. L. and Carvalho, J. E. M.}, title = {Effects of soil water content on soil respiration in forests and cattle pastures of eastern Amazonia}, journal = {Biogeochemistry}, year = {2000}, volume = {48}, number = {1}, pages = {53--69}, url = {://WOS:000083804900004}, doi = {https://doi.org/10.1023/a:1006204113917} } |
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Davidson, E.A., Sa, T.D.d.A., Carvalho, C.J.R., Figueiredo, R.d.O., Kato, M.d.S.A. and Ishida, F.Y. | An integrated greenhouse gas assessment of an alternative to slash-and-burn agriculture in eastern Amazonia | 2008 | Global Change Biology Vol. 14(5), pp. 998-1007 |
article | DOI URL |
Abstract: Fires set for slash-and-burn agriculture contribute to the current unsustainable accumulation of atmospheric greenhouse gases, and they also deplete the soil of essential nutrients, which compromises agricultural sustainability at local scales. Integrated assessments of greenhouse gas emissions have compared intensive cropping systems in industrialized countries, but such assessments have not been applied to common cropping systems of smallholder farmers in developing countries. We report an integrated assessment of greenhouse gas emissions in slash-and-burn agriculture and an alternative chop-and-mulch system in the Amazon Basin. The soil consumed atmospheric methane (CH4) under slash-and-burn treatment and became a net emitter of CH4 to the atmosphere under the mulch treatment. Mulching also caused about a 50% increase in soil emissions of nitric oxide and nitrous oxide and required greater use of fertilizer and fuel for farm machinery. Despite these significantly higher emissions of greenhouse gases during the cropping phase under the alternative chop-and-mulch system, calculated pyrogenic emissions in the slash-and-burn system were much larger, especially for CH4. The global warming potential CO2-equivalent emissions calculated for the entire crop cycles were at least five times lower in chop-and-mulch compared with slash-and-burn. The crop yields were similar for the two systems. While economic and logistical considerations remain to be worked out for alternatives to slash-and-burn, these results demonstrate a potential 'win-win' strategy for maintaining soil fertility and reducing net greenhouse gas emissions, thus simultaneously contributing to sustainability at both spatial scales. | |||||
BibTeX:
@article{davidson_integrated_2008, author = {Davidson, Eric A. and Sa, Tatiana Deane de Abreu and Carvalho, Claudip J. Reis and Figueiredo, Ricardo de Oliveira and Kato, Maria do Socorro A. and Ishida, Francoise Yoko}, title = {An integrated greenhouse gas assessment of an alternative to slash-and-burn agriculture in eastern Amazonia}, journal = {Global Change Biology}, year = {2008}, volume = {14}, number = {5}, pages = {998--1007}, url = {://WOS:000255463600005}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01542.x} } |
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Davidson, E.A., Nepstad, D.C., Ishida, F.Y. and Brando, P.M. | Effects of an experimental drought and recovery on soil emissions of carbon dioxide, methane, nitrous oxide, and nitric oxide in a moist tropical forest | 2008 | Global Change Biology Vol. 14(11), pp. 2582-2590 |
article | DOI URL |
Abstract: Changes in precipitation in the Amazon Basin resulting from regional deforestation, global warming, and El Nino events may affect emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and nitric oxide (NO) from soils. Changes in soil emissions of radiatively important gases could have feedback implications for regional and global climate. Here, we report the final results of a 5-year, large-scale (1 ha) throughfall exclusion experiment, followed by 1 year of recovery with natural throughfall, conducted in a mature evergreen forest near Santarem, Brazil. The exclusion manipulation lowered annual N2O emissions in four out of five treatment years (a natural drought year being the exception), and then recovered during the first year after the drought treatment stopped. Similarly, consumption of atmospheric CH4 increased under drought treatment, except during a natural drought year, and it also recovered to pretreatment values during the first year that natural throughfall was permitted back on the plot. No treatment effect was detected for NO emissions during the first 3 treatment years, but NO emissions increased in the fourth year under the extremely dry conditions of the exclusion plot during a natural drought. Surprisingly, there was no treatment effect on soil CO2 efflux in any year. The drought treatment provoked significant tree mortality and reduced the allocation of C to stems, but allocation of C to foliage and roots were less affected. Taken together, these results suggest that the dominant effect of throughfall exclusion on soil processes during this 6-year period was on soil aeration conditions that transiently affected CH4, N2O, and NO production and consumption. | |||||
BibTeX:
@article{davidson_effects_2008, author = {Davidson, Eric A. and Nepstad, Daniel C. and Ishida, Francoise Yoko and Brando, Paulo M.}, title = {Effects of an experimental drought and recovery on soil emissions of carbon dioxide, methane, nitrous oxide, and nitric oxide in a moist tropical forest}, journal = {Global Change Biology}, year = {2008}, volume = {14}, number = {11}, pages = {2582--2590}, url = {://WOS:000260307100010}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01694.x} } |
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Davidson, E.A., Neill, C., Krusche, A.V., Ballester, V.V.R., Markewitz, D. and Figueiredo, R.D. | Loss of nutrients from terrestrial ecosystems to streams and the atmosphere following land use change in Amazonia | 2004 | Vol. 153Ecosystems and Land Use Change, pp. 147-158 |
incollection | DOI URL |
Abstract: Rates of deforestation in the Amazon region have been accelerating, but the quantity and timing of nutrient losses from forested and deforested ecosystems are poorly understood. This paper investigates the broad variation in soil properties of the Amazon Basin as they influence transfers of plant nutrients from the terrestrial biosphere to the atmosphere and the aquatic biosphere. The dominant lowland soils are highly weathered Oxisols and Ultisols, but significant areas of Alfisols also exist, resulting in a wide range of weatherable primary minerals. Despite this considerable variation among Amazonian soils, a common feature in most mature lowland Amazonian forests is a conservative P cycle and excess N availability. In cattle pastures and secondary forests, however, low rates of internal terrestrial N cycling, low N export to streams, and low gaseous N emissions from soils are common, due to significant previous losses of N through repeated fire. Export of P to streams may increase or remain nearly undetectable after forest-to-pasture conversion, depending on soil type. Oxisols exhibit very low P export, whereas increased P export to pasture streams has been observed in Ultisols of western Amazonia. Calcium is mostly retained in terrestrial ecosystems following deforestation, although increased inputs to streams can be detected when background fluxes are naturally low. Because soil mineralogy and soil texture are both variable and important, the effects of land-use change on nutrient export to aquatic ecosystems and to the atmosphere must be understood within the context of varying soil properties across the Amazon Basin. | |||||
BibTeX:
@incollection{defries_loss_2004, author = {Davidson, E. A. and Neill, C. and Krusche, A. V. and Ballester, V. V. R. and Markewitz, D. and Figueiredo, R. D.}, title = {Loss of nutrients from terrestrial ecosystems to streams and the atmosphere following land use change in Amazonia}, booktitle = {Ecosystems and Land Use Change}, year = {2004}, volume = {153}, pages = {147--158}, url = {://WOS:000226789500011}, doi = {https://doi.org/10.1029/153gm12} } |
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Davidson, E. and Martinelli, L. | Nutrient Limitations to Secondary Forest Regrowth [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 299-310 |
incollection | |
BibTeX:
@incollection{m_keller_nutrient_2009, author = {Davidson, E.A. and Martinelli, L.A.}, title = {Nutrient Limitations to Secondary Forest Regrowth}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {299--310} } |
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Davidson, E.A., Ishida, F.Y. and Nepstad, D.C. | Effects of an experimental drought on soil emissions of carbon dioxide, methane, nitrous oxide, and nitric oxide in a moist tropical forest | 2004 | Global Change Biology Vol. 10(5), pp. 718-730 |
article | DOI URL |
Abstract: Changes in precipitation in the Amazon Basin resulting from regional deforestation, global warming, and El Nino events may affect emissions of carbon dioxide (CO(2)), methane (CH(4)), nitrous oxide (N(2)O), and nitric oxide (NO) from soils. Changes in soil emissions of radiatively important gases could have feedback implications for regional and global climates. Here we report results of a large-scale (1 ha) throughfall exclusion experiment conducted in a mature evergreen forest near Santarem, Brazil. The exclusion manipulation lowered annual N(2)O emissions by textgreater40% and increased rates of consumption of atmospheric CH(4) by a factor of textgreater4. No treatment effect has yet been detected for NO and CO(2) fluxes. The responses of these microbial processes after three rainy seasons of the exclusion treatment are characteristic of a direct effect of soil aeration on denitrification, methanogenesis, and methanotrophy. An anticipated second phase response, in which drought-induced plant mortality is followed by increased mineralization of C and N substrates from dead fine roots and by increased foraging of termites on dead coarse roots, has not yet been detected. Analyses of depth profiles of N(2)O and CO(2) concentrations with a diffusivity model revealed that the top 25 cm soil is the site of most of the wet season production of N(2)O, whereas significant CO(2) production occurs down to 100 cm in both seasons, and small production of CO(2) occurs to at least 1100 cm depth. The diffusivity-based estimates of CO(2) production as a function of depth were strongly correlated with fine root biomass, indicating that trends in belowground C allocation may be inferred from monitoring and modeling profiles of H(2)O and CO(2). | |||||
BibTeX:
@article{davidson_effects_2004, author = {Davidson, E. A. and Ishida, F. Y. and Nepstad, D. C.}, title = {Effects of an experimental drought on soil emissions of carbon dioxide, methane, nitrous oxide, and nitric oxide in a moist tropical forest}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {718--730}, url = {://WOS:000221421600014}, doi = {https://doi.org/10.1111/j.1365-2486.2004.00762.x} } |
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Davidson, E.A., Figueiredo, R.O., Markewitz, D. and Aufdenkampe, A.K. | Dissolved CO(2) in small catchment streams of eastern Amazonia: A minor pathway of terrestrial carbon loss | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115 |
article | DOI URL |
Abstract: Production of carbon dioxide (CO(2)) in soils can lead to supersaturation of dissolved free CO(2) (pCO(2)) in groundwater, which later evades to the atmosphere as groundwater enters streams and rivers. This process could be a significant pathway for return of terrestrially fixed C to the atmosphere. We measured pCO(2) monthly over two years at multiple stations along three streams from their headwaters in remnant mature forests through multiple land covers in Para, Brazil. The pCO(2) averaged 19,000 mu atm in headwaters and decreased to about 4,500 matm downstream. Similar values were measured in headwaters of two small pristine mature forest catchments. Two approaches were used to estimate groundwater pCO(2) evasion: assuming that headwater pCO(2) measurements reflected incoming groundwater pCO(2) or that all entering stream water was in equilibrium with previously measured deep soil CO(2). With these assumptions, losses from the terrestrial environment through aquatic evasion of pCO(2) would be 0.02-0.15 Mg C ha(-1) of land area yr(-1), which is about 2-3 orders of magnitude lower than annual estimates of soil respiration and net primary productivity. However, downstream pCO(2) values that appear to be in quasi-steady state indicate contributions from other C sources, such as aquatic primary production, soil erosion, dissolved organic matter, or litter inputs from streamside vegetation. Hence, lateral pCO(2) loss from groundwater to streams is minor for most of the terrestrial ecosystems of this region, although C loss to streams could be significant for net terrestrial budgets in riparian ecosystems or areas experiencing erosion. | |||||
BibTeX:
@article{davidson_dissolved_2010, author = {Davidson, Eric A. and Figueiredo, Ricardo O. and Markewitz, Daniel and Aufdenkampe, Anthony K.}, title = {Dissolved CO(2) in small catchment streams of eastern Amazonia: A minor pathway of terrestrial carbon loss}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, url = {://WOS:000282768500004}, doi = {https://doi.org/10.1029/2009jg001202} } |
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Davidson, E.A., de Carvalho, C.J.R., Vieira, I.C.G., Figueiredo, R.D., Moutinho, P., Ishida, F.Y., dos Santos, M.T.P., Guerrero, J.B., Kalif, K. and Saba, R.T. | Nitrogen and phosphorus limitation of biomass growth in a tropical secondary forest | 2004 | Ecological Applications Vol. 14(4), pp. S150-S163 |
article | URL |
Abstract: Understanding secondary successional processes in Amazonian terrestrial ecosystems is becoming increasingly important as continued deforestation expands the area that has become secondary forest, or at least has been through a recent phase of secondary forest growth. Most Amazonian soils are highly weathered and relatively nutrient poor, but the role of nutrients as a factor determining successional processes is unclear. Soils testing and chronosequence studies have yielded equivocal results regarding the possible role of nutrient limitation. The objective of this paper is to report the first two years' results of a nitrogen (N) and phosphorus (P) fertilization experiment in a 6-yr-old secondary forest growing on an abandoned cattle pasture on a clayey Oxisol. Growth of remnant grasses responded significantly to the N + P treatment, whereas tree biomass increased significantly following N-only and N + P treatments. The plants took up about 10% of the 50 kg P/ha of the first year's application, and recovery in soil fractions could account for the rest. The trees took up about 20% of the 100 kg N/ha of the first year's application. No changes in soil inorganic N, soil microbial biomass N, or litter decomposition rates have been observed so far, but soil faunal abundances increased in fertilized plots relative to the control in the second year of the study. A pulse of nitric oxide and nitrous oxide emissions was measured in the N-treated plots only shortly after the second year's application. Net N mineralization and net nitrification assays demonstrated strong immobilization potential, indicating that much of the N was probably retained in the large soil organic-N pool. Although P availability is low in these soils and may partially limit biomass growth, the most striking result of this study so far is the significant response of tree growth to N fertilization. Repeated fire and other losses of N from degraded pastures may render tree growth N limited in some young Amazonian forests. Changes in species composition and monitoring of long-term effects on biomass accumulation will be addressed as this experiment is continued. | |||||
BibTeX:
@article{davidson_nitrogen_2004, author = {Davidson, E. A. and de Carvalho, C. J. R. and Vieira, I. C. G. and Figueiredo, R. D. and Moutinho, P. and Ishida, F. Y. and dos Santos, M. T. P. and Guerrero, J. B. and Kalif, K. and Saba, R. T.}, title = {Nitrogen and phosphorus limitation of biomass growth in a tropical secondary forest}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S150--S163}, url = {://WOS:000223269000014} } |
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Davidson, E.A., de Carvalho, C.J.R., Figueira, A.M., Ishida, F.Y., Ometto, J.P.H.B., Nardoto, G.B., Saba, R.T., Hayashi, S.N., Leal, E.C., Vieira, I.C.G. and Martinelli, L.A. | Recuperation of nitrogen cycling in Amazonian forests following agricultural abandonment | 2007 | Nature Vol. 447(7147), pp. 995-U6 |
article | DOI URL |
Abstract: Phosphorus ( P) is generally considered the most common limiting nutrient for productivity of mature tropical lowland forests growing on highly weathered soils(1-5). It is often assumed that P limitation also applies to young tropical forests, but nitrogen (N) losses during land-use change may alter the stoichiometric balance of nutrient cycling processes. In the Amazon basin, about 16% of the original forest area has been cleared(6), and about 30 - 50% of cleared land is estimated now to be in some stage of secondary forest succession following agricultural abandonment(7). Here we use forest age chronosequences to demonstrate that young successional forests growing after agricultural abandonment on highly weathered lowland tropical soils exhibit conservative N-cycling properties much like those of N-limited forests on younger soils in temperate latitudes. As secondary succession progresses, N-cycling properties recover and the dominance of a conservative P cycle typical of mature lowland tropical forests re-emerges. These successional shifts in N: P cycling ratios with forest age provide a mechanistic explanation for initially lower and then gradually increasing soil emissions of the greenhouse gas nitrous oxide (N2O). The patterns of N and P cycling during secondary forest succession, demonstrated here over decadal timescales, are similar to N- and P-cycling patterns during primary succession as soils age over thousands and millions of years, thus revealing that N availability in terrestrial ecosystems is ephemeral and can be disrupted by either natural or anthropogenic disturbances at several timescales. | |||||
BibTeX:
@article{davidson_recuperation_2007, author = {Davidson, Eric A. and de Carvalho, Claudio J. Reis and Figueira, Adelaine Michela and Ishida, Francoise Yoko and Ometto, Jean Pierre H. B. and Nardoto, Gabriela B. and Saba, Renata Tuma and Hayashi, Sanae N. and Leal, Eliane C. and Vieira, Ima Celia G. and Martinelli, Luiz A.}, title = {Recuperation of nitrogen cycling in Amazonian forests following agricultural abandonment}, journal = {Nature}, year = {2007}, volume = {447}, number = {7147}, pages = {995--U6}, note = {Edition: 2007/06/22}, url = {://WOS:000247373100045}, doi = {https://doi.org/10.1038/nature05900} } |
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Davidson, E.A., de Araújo, A.C., Artaxo, P., Balch, J.K., Brown, I.F., C. Bustamante, M.M., Coe, M.T., DeFries, R.S., Keller, M., Longo, M., Munger, J.W., Schroeder, W., Soares-Filho, B.S., Souza, C.M. and Wofsy, S.C. | The Amazon basin in transition | 2012 | Nature Vol. 481(7381), pp. 321-328 |
article | DOI URL |
Abstract: A synthesis of recent research shows that the effects of human actions have already altered the regional hydrology and energy balance of parts of the Amazon basin, and that interactions between deforestation, fire and climate change are likely to further alter carbon storage, precipitation patterns and river discharge. | |||||
BibTeX:
@article{davidson_amazon_2012, author = {Davidson, Eric A. and de Araújo, Alessandro C. and Artaxo, Paulo and Balch, Jennifer K. and Brown, I. Foster and C. Bustamante, Mercedes M. and Coe, Michael T. and DeFries, Ruth S. and Keller, Michael and Longo, Marcos and Munger, J. William and Schroeder, Wilfrid and Soares-Filho, Britaldo S. and Souza, Carlos M. and Wofsy, Steven C.}, title = {The Amazon basin in transition}, journal = {Nature}, year = {2012}, volume = {481}, number = {7381}, pages = {321--328}, url = {https://doi.org/10.1038/nature10717}, doi = {https://doi.org/10.1038/nature10717} } |
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Davidson, E.A., Belk, E. and Boone, R.D. | Soil water content and temperature as independent or confounded factors controlling soil respiration in a temperate mixed hardwood forest | 1998 | Global Change Biology Vol. 4(2), pp. 217-227 |
article | DOI URL |
Abstract: Variation in soil temperature can account for most of the seasonal and diel variation in soil CO2 efflux, but the temperature effect is not always consistent, and other factors such as soil water content are known to influence soil respiration. The objectives of this research were to study the spatial and temporal variation in soil respiration in a temperate forested landscape and to evaluate temperature and soil water functions as predictors of soil respiration. Soil CO2 auxes were measured with chambers throughout an annual cycle in six study areas at the Harvard Forest in central Massachusetts that include soil drainage classes from well drained to very poorly drained. The mean annual estimate of soil CO2 efflux was 7.2 Mg ha(-1), but ranged from 5.3 in the swamp site to 8.5 in a well-drained site, indicating that landscape heterogeneity is related to soil drainage class. An exponential function relating CO2 fluxes to soil temperature accounted for 80% of the seasonal variation in fluxes across all sites (Q(10) = 3.9), but the Q(10) ranged from 3.4 to 5.6 for the individual study sites. A significant drought in 1995 caused rapid declines in soil respiration rates in August and September in five of the six sites (a swamp site was the exception). This decline in CO2 fluxes correlated exponentially with decreasing soil matric potential, indicating a mechanistic effect of drought stress. At moderate to high water contents, however, soil water content was negatively correlated with soil temperature, which precluded distinguishing between the effects of these two confounded factors on CO2 flux. Occurrence of high Q(10) values and variation in Q(10) values among sites may be related to: (i) confounding effects of high soil water content; (ii) seasonal and diel patterns in root respiration and turnover of fine roots that are linked to above ground phenology and metabolism; and (iii) variation in the depth where CO2 is produced. The Q(10) function can yield reasonably good predictions of annual fluxes of CO2, but it is a simplification that masks responses of root and microbial processes to variation in temperature and water content throughout the soil. | |||||
BibTeX:
@article{davidson_soil_1998, author = {Davidson, E. A. and Belk, E. and Boone, R. D.}, title = {Soil water content and temperature as independent or confounded factors controlling soil respiration in a temperate mixed hardwood forest}, journal = {Global Change Biology}, year = {1998}, volume = {4}, number = {2}, pages = {217--227}, url = {://WOS:000072141800010}, doi = {https://doi.org/10.1046/j.1365-2486.1998.00128.x} } |
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Davidson, E.A., Asner, G.P., Stone, T.A., Neill, C. and Figueiredo, R.O. | Objective indicators of pasture degradation from spectral mixture analysis of Landsat imagery | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: Degradation of cattle pastures is a management concern that influences future land use in Amazonia. However, "degradation'' is poorly defined and has different meanings for ranchers, ecologists, and policy makers. Here we analyze pasture degradation using objective scalars of photosynthetic vegetation (PV), nonphotosynthetic vegetation (NPV), and exposed soil ( S) derived from Landsat imagery. A general, probabilistic spectral mixture model decomposed satellite spectral reflectance measurements into subpixel estimates of PV, NPV, and S covers at ranches in western and eastern Amazonia. Most pasture management units at all ranches fell along a single line of decreasing PV with increasing NPV and S, which could be considered a degradation continuum. The ranch with the highest stocking densities and most intensive management had greater NPV and S than a less intensively managed ranch. The number of liming, herbiciding, and disking treatments applied to each pasture management unit was positively correlated with NPV and negatively correlated with PV. Although these objective scalars revealed signs of degradation, intensive management kept exposed soil to textless40% cover and maintained economically viable cattle production over several decades. In ranches with few management inputs, the high PV cover in young pastures declined with increasing pasture age, while NPV and S increased, even where grazing intensity was low. Both highly productive pastures and vigorous regrowth of native vegetation cause high PV values. Analysis of spectral properties holds promise for identifying areas where grazing intensity has exceeded management inputs, thus increasing coverage of senescent foliage and exposed soil. | |||||
BibTeX:
@article{davidson_objective_2008, author = {Davidson, Eric A. and Asner, Gregory P. and Stone, Thomas A. and Neill, Christopher and Figueiredo, Ricardo O.}, title = {Objective indicators of pasture degradation from spectral mixture analysis of Landsat imagery}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000257998900001}, doi = {https://doi.org/10.1029/2007jg000622} } |
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Davidson, E.A. and Artaxo, P. | Globally significant changes in biological processes of the Amazon Basin: results of the Large-scale Biosphere-Atmosphere Experiment | 2004 | Global Change Biology Vol. 10(5), pp. 519-529 |
article | DOI URL |
Abstract: The Amazon River, its huge basin, and the changes in biological processes that are rapidly occurring in this region are unquestionably of global significance. Hence, Global Change Biology is delighted to host a special thematic issue devoted to the Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA), which is a multinational, interdisciplinary research program led by Brazil. The goal of LBA is no less modest than its subject: to understand how Amazonia functions as a regional entity in the Earth system and how these functions are changing as a result of ongoing changes in land use. This compilation of 26 papers resulting from LBA-related research covers a broad range of topics: forest stocks of carbon (C) and nitrogen (N); fluxes of greenhouse gases and volatile organic compounds from vegetation, soils and wetlands; mapping and modeling land-use change, fire risk, and soil properties; measuring changes caused by logging, pasturing and cultivating; and new research approaches in meteorology to estimate nocturnal fluxes of C from forests and pastures. Some important new synthesis can be derived from these and other studies. The aboveground biomass of intact Amazonian forests appears to be a sink for atmospheric carbon dioxide (CO(2)), while the wetlands and soils are a net source of atmospheric methane (CH(4)) and nitrous oxide (N(2)O), respectively. Land-use change has, so far, had only a minor effect on basin-wide emissions of CH(4) and N(2)O, but the net effect of deforestation and reforestation appears to be a significant net release of CO(2) to the atmosphere. The sum of the 100-year global warming potentials (GWP) of these annual sources and sinks of CH(4), N(2)O, and CO(2) indicate that the Amazonian forest-river system currently may be nearly balanced in terms of the net GWP of these biogenic atmospheric gases. Of course, large uncertainties remain for these estimates, but the papers published here demonstrate tremendous progress, and also large remaining hurdles, in narrowing these uncertainties in our understanding of how Amazonia functions as a regional entity in the Earth system. | |||||
BibTeX:
@article{davidson_globally_2004, author = {Davidson, E. A. and Artaxo, P.}, title = {Globally significant changes in biological processes of the Amazon Basin: results of the Large-scale Biosphere-Atmosphere Experiment}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {519--529}, url = {://WOS:000221421600001}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00779.x} } |
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Davidson, E., Araujo, A., Artaxo, P., Balch, J., Brown, F., Bustamante, M., Coe, M., DeFries, R., Keller, M., Longo, M., Munger, J., Schroeder, W., Soares-Filho, B., Souza Jr, C. and Wofsy, S. | The Amazon basin in transition | 2012 | Nature Vol. 481(321), pp. doi:10.1038/nature10717 |
article | DOI URL |
Abstract: Agricultural expansion and climate variability have become important agents of disturbance in the Amazon basin. Recent studies have demonstrated considerable resilience of Amazonian forests to moderate annual drought, but they also show that interactions between deforestation, fire and drought potentially lead to losses of carbon storage and changes in regional precipitation patterns and river discharge. Although the basin-wide impacts of land use and drought may not yet surpass the magnitude of natural variability of hydrologic and biogeochemical cycles, there are some signs of a transition to a disturbance-dominated regime. These signs include changing energy and water cycles in the southern and eastern portions of the Amazon basin. | |||||
BibTeX:
@article{davidson_amazon_2012-1, author = {Davidson, E.A. and Araujo, A.C. and Artaxo, P. and Balch, J.K. and Brown, F. and Bustamante, M.M.C. and Coe, M.T. and DeFries, R.S. and Keller, M. and Longo, M. and Munger, J.W. and Schroeder, W. and Soares-Filho, B.S. and Souza Jr, C.M. and Wofsy, S.C.}, title = {The Amazon basin in transition}, journal = {Nature}, year = {2012}, volume = {481}, number = {321}, pages = {doi:10.1038/nature10717}, note = {Edition: 2012/01/20}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22258611 http://www.nature.com/nature/journal/v481/n7381/pdf/nature10717.pdf}, doi = {https://doi.org/10.1038/nature10717} } |
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Davidson, E., Lefebvre, P.A., Brando, P.M., Ray, D.M., Trumbore, S.E., Solorzano, L.A., Ferreira, J.N., Bustamante, M.M.d.C. and Nepstad, D.C. | Carbon Inputs and Water Uptake in Deep Soils of an Eastern Amazon Forest | 2011 | Forest Science Vol. 57(1), pp. 51-58 |
article | URL |
Abstract: Rooting depth affects soil profiles of water uptake and carbon inputs. Here we explore the importance of deep roots in a mature tropical forest of eastern Amazonia, where a throughfall exclusion experiment was conducted to test the resilience of the forest to experimentally induced drought. We hypothesized that soil water depletion occurred below the depth previously measured by sensors in 11-m-deep soil pits and that only a small root biomass is necessaiy to affect water uptake and the isotopic signature of soil CO(2). A noninvasive electrical profiling method demonstrated greater depletion of soil water in the 11-18 m depth increment in the exclusion ploi compared with the control plot by the end of the 3rd year of the experiment. A fine root biomass of only 0.1 g/cm(3) measured at 3-6 m was sufficient for soil water drawdown and for imparting an isotopic signature of modern soil (14)CO(2) in both plots. A soil (13)CO(2) profile indicated drought stress in the exclusion plot. Fine root inputs of organic C to deep soils are small with respect to the carbon dynamics of the forest, but the deep rooting habit clearly affects the ecosystem water balance and profiles of soil CO(2). FOR. Sct. 57(1):51-58. | |||||
BibTeX:
@article{davidson_carbon_2011, author = {Davidson, Eric and Lefebvre, Paul A. and Brando, Paulo M. and Ray, David M. and Trumbore, Susan E. and Solorzano, Luis A. and Ferreira, Joice N. and Bustamante, Mercedes M. da C. and Nepstad, Daniel C.}, title = {Carbon Inputs and Water Uptake in Deep Soils of an Eastern Amazon Forest}, journal = {Forest Science}, year = {2011}, volume = {57}, number = {1}, pages = {51--58}, url = {://WOS:000286956900008} } |
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Darbyshire, E., Morgan, W.T., Allan, J.D., Liu, D., Flynn, M.J., Dorsey, J.R., O’Shea, S.J., Lowe, D., Szpek, K., Marenco, F., Johnson, B.T., Bauguitte, S., Haywood, J.M., Brito, J.F., Artaxo, P., Longo, K.M. and Coe, H. | The vertical distribution of biomass burning pollution over tropical South America from aircraft in situ measurements during SAMBBA [BibTeX] |
2019 | Atmos. Chem. Phys. Vol. 19, pp. 5771-5790 |
article | |
BibTeX:
@article{darbyshire_vertical_2019, author = {Darbyshire, E. and Morgan, William T. and Allan, James D. and Liu, Dantong and Flynn, Michael J. and Dorsey, James R. and O’Shea, Sebastian J. and Lowe, Douglas and Szpek, Kate and Marenco, Franco and Johnson, Ben T. and Bauguitte, Stephane and Haywood, Jim M. and Brito, Joel F. and Artaxo, Paulo and Longo, Karla M. and Coe, Hugh}, title = {The vertical distribution of biomass burning pollution over tropical South America from aircraft in situ measurements during SAMBBA}, journal = {Atmos. Chem. Phys.}, year = {2019}, volume = {19}, pages = {5771--5790} } |
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Dantas, S., V.P.R. da, C., A.C.L. da, C. and G.F.B. das, V. | Fluxos de calor no dossel vegetativo e infiltração de água no solo, em floresta tropical [BibTeX] |
2011 | Revista Brasileira de Engenharia Agrícola e Ambiental Vol. 15(12), pp. 1266-1274 |
article | |
BibTeX:
@article{dantas_fluxos_2011, author = {Dantas, Silva, V.P.R. da, Costa, A.C.L. da, Chagas, G.F.B. das, V.A.}, title = {Fluxos de calor no dossel vegetativo e infiltração de água no solo, em floresta tropical}, journal = {Revista Brasileira de Engenharia Agrícola e Ambiental}, year = {2011}, volume = {15}, number = {12}, pages = {1266--1274} } |
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D'Angelo, S.A., Andrade, A.C.S., Laurance, S.G., Laurance, W.F. and Mesquita, R.C.G. | Inferred causes of tree mortality in fragmented and intact Amazonian forests [BibTeX] |
2004 | Journal of Tropical Ecology Vol. 20, pp. 243-246 |
article | DOI URL |
BibTeX:
@article{dangelo_inferred_2004, author = {D'Angelo, S. A. and Andrade, A. C. S. and Laurance, S. G. and Laurance, W. F. and Mesquita, R. C. G.}, title = {Inferred causes of tree mortality in fragmented and intact Amazonian forests}, journal = {Journal of Tropical Ecology}, year = {2004}, volume = {20}, pages = {243--246}, url = {://WOS:000220913000015}, doi = {https://doi.org/10.1017/s0266467403001032} } |
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Danelichen, V., Biudes, M., Velasque, M., Machado, N., Gomes, R., Vourlitis, G. and Nogueira, J. | Estimating of gross primary production in an Amazon-Cerrado transitional forest using MODIS and Landsat imagery [BibTeX] |
2015 | An. Acad. Bras. Ciênc. Vol. 87(3) |
article | |
BibTeX:
@article{danelichen_estimating_2015, author = {Danelichen, V.H.M. and Biudes, M.S. and Velasque, M.C.S. and Machado, N.G. and Gomes, R.S.R. and Vourlitis, G.l. and Nogueira, J.S.}, title = {Estimating of gross primary production in an Amazon-Cerrado transitional forest using MODIS and Landsat imagery}, journal = {An. Acad. Bras. Ciênc.}, year = {2015}, volume = {87}, number = {3} } |
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D'Amelio, M.T.S., Gatti, L.V., Miller, J.B. and Tans, P. | Regional N(2)O fluxes in Amazonia derived from aircraft vertical profiles | 2009 | Atmospheric Chemistry and Physics Vol. 9(22), pp. 8785-8797 |
article | URL |
Abstract: Nitrous oxide (N(2)O) is the third most important anthropogenic greenhouse gas. Globally, the main sources of N(2)O are nitrification and denitrification in soils. About two thirds of the soil emissions occur in the tropics and approximately 20% originate in wet rainforest ecosystems, like the Amazon forest. The work presented here involves aircraft vertical profiles of N(2)O from the surface to 4 km over two sites in the Eastern and Central Amazon: Tapajos National Forest (SAN) and Cuieiras Biologic Reserve (MAN), and the estimation of N(2)O fluxes for regions upwind of these sites. To our knowledge, these regional scale N(2)O measurements in Amazonia are unique and represent a new approach to looking regional scale emissions. The fluxes upwind of MAN exhibited little seasonality, and the annual mean was 2.1 +/- 1.0 mg N(2)O m(-2) day(-1), higher than that for fluxes upwind of SAN, which averaged 1.5 +/- 1.6 mg N(2)O m(-2) day(-1). The higher rainfall around the MAN site could explain the higher N(2)O emissions, as a result of increased soil moisture accelerating microbial nitrification and denitrification processes. For fluxes from the coast to SAN seasonality is present for all years, with high fluxes in the months of March through May, and in November through December. The first peak of N(2)O flux is strongly associated with the wet season. The second peak of high N(2)O flux recorded at SAN occurs during the dry season and can not be easily explained. However, about half of the dry season profiles exhibit significant correlations with CO, indicating a larger than expected source of N(2)O from biomass burning. The average CO:N(2)O ratio for all profiles sampled during the dry season is 94 +/- 77 mol CO:mol N(2)O and suggests a larger biomass burning contribution to the global N(2)O budget than previously reported. | |||||
BibTeX:
@article{damelio_regional_2009, author = {D'Amelio, M. T. S. and Gatti, L. V. and Miller, J. B. and Tans, P.}, title = {Regional N(2)O fluxes in Amazonia derived from aircraft vertical profiles}, journal = {Atmospheric Chemistry and Physics}, year = {2009}, volume = {9}, number = {22}, pages = {8785--8797}, url = {://WOS:000272232500011} } |
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Dalmolin, A.C., Lobo, F.d.A., Vourlitis, G., Priscila Russani Silva, Dalmagro, H.J., Antunes Jr., M.Z. and Ortız, C.E.R. | Is the dry season an important driver of phenology and growth for two Brazilian savanna tree species with contrasting leaf habits? [BibTeX] |
2015 | Plant Ecology Vol. 216, pp. 407-417 |
article | DOI |
BibTeX:
@article{dalmolin_is_2015, author = {Dalmolin, Andrea Carla and Lobo, Francisco de Almeida and Vourlitis, George and Priscila Russani Silva and Dalmagro, Higo Jose and Antunes Jr., Mario Zortea and Ortız, Carmen Eugenia Rodriguez}, title = {Is the dry season an important driver of phenology and growth for two Brazilian savanna tree species with contrasting leaf habits?}, journal = {Plant Ecology}, year = {2015}, volume = {216}, pages = {407--417}, doi = {https://doi.org/10.1007/s11258-014-0445-5} } |
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D'Almeida, C., Vorosmarty, C.J., Marengo, J.A., Hurtt, G.C., Dingman, S.L. and Keim, B.D. | A water balance model to study the hydrological response to different scenarios of deforestation in Amazonia | 2006 | Journal of Hydrology Vol. 331(1-2), pp. 125-136 |
article | DOI URL |
Abstract: Amazonia encloses some of the largest watersheds in the world, experiencing substantial amounts of rainfall annually and producing more runoff to the ocean than any other region. Amazonia experiences one of the highest rates of deforestation in the world and the hydrological effects of such a disturbance have already been investigated by several studies. Contrasting results exist, especially when different scales and degrees of heterogeneity are considered. This paper assesses the dependency of the hydrological impact of deforestation on these factors through application of a gridded water balance model. The model simulates different scenarios of deforestation based on straightforward water balance calculations. In all experiments performed, the scenarios conform to observations of decreased evapotranspiration within disturbed sites. Initially, by implying an uncoupling between small deforested areas and circulation, the model suggests an increase in runoff locally. However, when the land-atmosphere coupling caused by intermediate levels of deforestation is reproduced through deviations on circulation, the model confirms that the water cycle may or may not become regionally accelerated, depending on the degree of heterogeneity associated. Finally, by simulating a scenario of complete deforestation, the model confirms expectations of a less intense water cycle in Amazonia. Due to the broad range of numerical models and observation networks currently available, the importance of the proper representation of both scale and heterogeneity of deforestation to the correct assessment of its hydrological effects is emphasized. Despite our model results, there is need for more mechanistic studies on coupled land-surface and atmosphere interactions under varying conditions. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{dalmeida_water_2006, author = {D'Almeida, Cassiano and Vorosmarty, Charles J. and Marengo, Jose A. and Hurtt, George C. and Dingman, S. Lawrence and Keim, Barry D.}, title = {A water balance model to study the hydrological response to different scenarios of deforestation in Amazonia}, journal = {Journal of Hydrology}, year = {2006}, volume = {331}, number = {1-2}, pages = {125--136}, url = {://WOS:000242329500011}, doi = {https://doi.org/10.1016/j.jhydrol.2006.05.027} } |
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D'Almeida, C., Vorosmarty, C.J., Hurtt, G.C., Marengo, J.A., Dingman, S.L. and Keim, B.D. | The effects of deforestation on the hydrological cycle in Amazonia: a review on scale and resolution | 2007 | International Journal of Climatology Vol. 27(5), pp. 633-647 |
article | DOI URL |
Abstract: This paper reviews the effects of deforestation on the hydrological cycle in Amazonia according to recent modeling and observational studies performed within different spatial scales and resolutions. The predictions that follow from future scenarios of a complete deforestation in the region point to a restrained water cycle, while the simulated effects of small, disturbed areas show a contrasting tendency. Differences between coarsely spatially averaged observations and finely sampled data sets have also been encountered. These contrasts are only partially explained by the different spatial resolutions among models and observations, since they seem to be further associated with the weakening of precipitation recycling under scenarios of extensive deforestation and with the potential intensification of convection over areas of land-surface heterogeneity. Therefore, intrinsic and interrelated scale and heterogeneity dependencies on the impact of deforestation in Amazonia on the hydrological cycle are revealed and the acknowledgement of the relevance of these dependencies sets a few challenges for the future. Copyright (c) 2007 Royal Meteorological Society. | |||||
BibTeX:
@article{dalmeida_effects_2007, author = {D'Almeida, Cassiano and Vorosmarty, Charles J. and Hurtt, George C. and Marengo, Jose A. and Dingman, S. Lawrence and Keim, Barry D.}, title = {The effects of deforestation on the hydrological cycle in Amazonia: a review on scale and resolution}, journal = {International Journal of Climatology}, year = {2007}, volume = {27}, number = {5}, pages = {633--647}, url = {://WOS:000246381000006}, doi = {https://doi.org/10.1002/joc.1475} } |
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Dalmagro, F., Vourlitis, G.l., Dalmolin, Â.C., Antunes, M.Z., Ortíz, C.E.R., de S. Nogueira José, H.J. and de A. Lobo | Photosynthetic response of a wetland- and an upland-adapted tree species to seasonal variations in hydrology in the Brazilian Cerrado and Pantanal [BibTeX] |
2016 | Acta Physiologiae Plantarum Vol. 38, pp. 1-10 |
article | |
BibTeX:
@article{dalmagro_photosynthetic_2016, author = {Dalmagro, Francisco ; Vourlitis, George l. ; Dalmolin, Ândrea C. ; Antunes, Mario Z. ; Ortíz, Carmen E. R. ; de S. Nogueira, José, Higo J. ; de A. Lobo}, title = {Photosynthetic response of a wetland- and an upland-adapted tree species to seasonal variations in hydrology in the Brazilian Cerrado and Pantanal}, journal = {Acta Physiologiae Plantarum}, year = {2016}, volume = {38}, pages = {1--10} } |
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Dalmagro, H.J., Lathuilliere, M.J., Vourlitis, G.L., Campos, R.C., Pinto Jr, O.B., Johnson, M.S., Ortız, C.E., Lobo, F.d.A. and Couto, E.G. | Physiological responses to extreme hydrologicalevents in the Pantanal wetland: heterogeneity of aplant community containing super-dominant species [BibTeX] |
2016 | Journal of Vegetation Science Vol. 27, pp. 568-577 |
article | |
BibTeX:
@article{dalmagro_physiological_2016, author = {Dalmagro, Higo J. and Lathuilliere, Michael J. and Vourlitis, George L. and Campos, Roberto C. and Pinto Jr, Osvaldo Borges and Johnson, Mark S. and Ortız, Carmen E.R. and Lobo, Francisco de A. and Couto, Eduardo G.}, title = {Physiological responses to extreme hydrologicalevents in the Pantanal wetland: heterogeneity of aplant community containing super-dominant species}, journal = {Journal of Vegetation Science}, year = {2016}, volume = {27}, pages = {568--577} } |
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Dalmagro, H.J., Lathuillière, M.J., Hawthorne, I., Morais, D.D., Pinto Jr, O.B., Couto, E.G. and Johnson, M.S. | Carbon biogeochemistry of a flooded Pantanal forest over three annual flood cycles [BibTeX] |
2018 | Biogeochemistry Vol. 139(1), pp. 1-18 |
article | |
BibTeX:
@article{dalmagro_carbon_2018, author = {Dalmagro, Higo J. and Lathuillière, Michael J. and Hawthorne, Iain and Morais, Douglas D. and Pinto Jr, Osvaldo B. and Couto, Eduardo G. and Johnson, Mark S.}, title = {Carbon biogeochemistry of a flooded Pantanal forest over three annual flood cycles}, journal = {Biogeochemistry}, year = {2018}, volume = {139}, number = {1}, pages = {1--18} } |
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Dalmagro, H.J., Arruda, P.H.Z.d., Vourlitis, G.L., Lathuillière, M., Nogueira, J.d.S., Couto, E.G. and Johnson, M.S. | Radiative forcing of methane fluxes offsets net carbon dioxide uptake for a tropical flooded forest [BibTeX] |
2019 | Global Change Biology Vol. 25(6), pp. 1967-1981 |
article | DOI |
BibTeX:
@article{dalmagro_radiative_2019, author = {Dalmagro, H. J. and Arruda, P. H. Z. de and Vourlitis, George L. and Lathuillière, M.J. and Nogueira, J. de S. and Couto, E. G. and Johnson, M. S.}, title = {Radiative forcing of methane fluxes offsets net carbon dioxide uptake for a tropical flooded forest}, journal = {Global Change Biology}, year = {2019}, volume = {25}, number = {6}, pages = {1967--1981}, doi = {https://doi.org/10.1111/gcb.14615} } |
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Dalagnol, R., Phillips, O.L., Gloor, E., Galvão, L.S., Wagner, F.H., Locks, C.J. and Aragão, L.E.O.C... | Quantifying Canopy Tree Loss and Gap Recovery in Tropical Forests under Low-Intensity Logging Using VHR Satellite Imagery and Airborne LiDAR [BibTeX] |
2019 | Remote Sensing Vol. 11, pp. 817 |
article | |
BibTeX:
@article{dalagnol_quantifying_2019, author = {Dalagnol, Ricardo and Phillips, Oliver L. and Gloor, Emanuel and Galvão, Lênio S. and Wagner, Fabien H. and Locks, Charton J. and Aragão, Luiz E. O. C. .}, title = {Quantifying Canopy Tree Loss and Gap Recovery in Tropical Forests under Low-Intensity Logging Using VHR Satellite Imagery and Airborne LiDAR}, journal = {Remote Sensing}, year = {2019}, volume = {11}, pages = {817} } |
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da Silva, V.D.P.R., Almeida, R.S.R., Dantas, V.D.A., da Costa, A.C.L., Singh, V.P. and Chagas, G.F.B. | Sensible and Latent Heat Storage Fluxes within the Canopy Air-Space in the Amazon Rainforest [BibTeX] |
2012 | Journal Forest Research Vol. 1(2) |
article | DOI |
BibTeX:
@article{da_silva_sensible_2012, author = {da Silva, V. D. P. R. and Almeida, R. S. R. and Dantas, V. D. A. and da Costa, A. C. L. and Singh, V. P. and Chagas, G. F. B.}, title = {Sensible and Latent Heat Storage Fluxes within the Canopy Air-Space in the Amazon Rainforest}, journal = {Journal Forest Research}, year = {2012}, volume = {1}, number = {2}, doi = {https://doi.org/10.4172/jfor.1000106} } |
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da Silva, H., Gonçalves, W., Bezerra, B., Santos e Silva, C., Oliveira, C. and Mutti, P. | Analysis of the Influence of Deforestation on the Microphysical Parameters of Clouds in the Amazon. | 2022 | Remote Sensing Vol. 14(21), pp. 5353 |
article | DOI URL |
Abstract: Studies have shown that deforestation can cause changes in energy, moisture, and precipitation flows, with implications for local and regional climate. These studies generally focus on … | |||||
BibTeX:
@article{da_silva_analysis_2022, author = {da Silva, HJF and Gonçalves, WA and Bezerra, BG and Santos e Silva, CM and Oliveira, CPd and Mutti, PR}, title = {Analysis of the Influence of Deforestation on the Microphysical Parameters of Clouds in the Amazon.}, journal = {Remote Sensing}, year = {2022}, volume = {14}, number = {21}, pages = {5353}, url = {https://www.mdpi.com/1906528}, doi = {https://doi.org/10.3390/rs14215353} } |
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da Rocha, H.R., Manzi, A.O. and Shuttleworth, J. | Evapotranspiration [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 261-272 |
incollection | |
BibTeX:
@incollection{m_keller_evapotranspiration_2009, author = {da Rocha, H. R. and Manzi, Antonio O. and Shuttleworth, Jim}, title = {Evapotranspiration}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {261--272} } |
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da Costa, A.C.L., Rowland, L., Oliveira, R., Oliveira, A.A.R., Binks, O.J., Salmon, Y., Vasconcelos, S.S., Junior, J.A.S., Ferreira, L.V., Poyatos, R., Mencuccini, M. and Meir, P. | Stand dynamics modulate water cycling and mortality risk in droughted tropical forest [BibTeX] |
2018 | GLOBAL CHANGE BIOLOGY Vol. 24, pp. 249-258 |
article | |
BibTeX:
@article{da_costa_stand_2018, author = {da Costa, A. C. L. and Rowland, L. and Oliveira, R.S. and Oliveira, A. A. R. and Binks, O. J. and Salmon, Y. and Vasconcelos, S. S. and Junior, J. A. S. and Ferreira, L. V. and Poyatos, R. and Mencuccini, M. and Meir, P.}, title = {Stand dynamics modulate water cycling and mortality risk in droughted tropical forest}, journal = {GLOBAL CHANGE BIOLOGY}, year = {2018}, volume = {24}, pages = {249--258} } |
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Czikowsky, M.J. and Fitzjarrald, D.R. | Detecting rainfall interception in an Amazonian rain forest with eddy flux measurements | 2009 | Journal of Hydrology Vol. 377(1-2), pp. 92-105 |
article | DOI URL |
Abstract: We introduce a new method to estimate rainfall interception and demonstrate its use for data obtained in an old-growth rain forest in the eastern Amazon basin The approach is to use eddy covariance evaporation observations to estimate the 'excess' evaporation that occurs following individual events. Ensemble averaged water vapor fluxes were calculated from original high frequency data both for rain event and for base state dry days. Interception was inferred from the difference between observed evaporation for selected times during and following rainfall events from baseline evaporation estimates. This method allows the interception evaporation to be directly measured rather than determined from the residual of incident precipitation and throughfall. in conventional studies, large differences in throughfall can occur on a site due to varying forest canopy density, structure and the appearance of canopy gaps. This problem is mitigated when using the current approach, which provides an average interception value over the flux footprint area. Identification of light rainfall events not detected by an on-site tipping bucket rain gauge was aided by the use of a ceilometer. The mean interception for all events in the study (daytime and nocturnal) was 11.6%, comparable to some recent conventional studies in this region. We found an approximately 15% increase of evaporative fraction on the rain days as compared to dry baseline days, with the energy being supplied by a corresponding decrease in the canopy heat storage. Since net radiation is used to scale the evaporation in this method, this method may be applicable to data from other tower sites in varying surface and climatic types. We did not find that bulk stomatal resistance vanishes just after rainfall. The effective bulk stomatal resistance can be used as the observational equivalent of the wet fraction of canopy parameter used in interception models. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{czikowsky_detecting_2009, author = {Czikowsky, Matthew J. and Fitzjarrald, David R.}, title = {Detecting rainfall interception in an Amazonian rain forest with eddy flux measurements}, journal = {Journal of Hydrology}, year = {2009}, volume = {377}, number = {1-2}, pages = {92--105}, url = {://WOS:000271125800010}, doi = {https://doi.org/10.1016/j.jhydrol.2009.08.002} } |
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Curran, L.M. and Trigg, S.N. | Sustainability science from space: Quantifying forest disturbance and land-use dynamics in the Amazon [BibTeX] |
2006 | Proceedings of the National Academy of Sciences of the United States of America Vol. 103(34), pp. 12663-12664 |
article | DOI URL |
BibTeX:
@article{curran_sustainability_2006, author = {Curran, Lisa M. and Trigg, Simon N.}, title = {Sustainability science from space: Quantifying forest disturbance and land-use dynamics in the Amazon}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2006}, volume = {103}, number = {34}, pages = {12663--12664}, note = {Edition: 2006/08/16}, url = {://WOS:000240035900004}, doi = {https://doi.org/10.1073/pnas.0605449103} } |
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Cunha, H.F.V., Andersen, K.M., Lugli, L.F., Santana, F.D., Aleixo, I.F., Moraes, A.M., Garcia, S., Di Ponzio, R., Mendoza, E.O., Brum, B., Rosa, J.S., Cordeiro, A.L., Portela, B.T.T., Ribeiro, G., Coelho, S.D., de Souza, S.T., Silva, L.S., Antonieto, F., Pires, M., Salomão, A.C., Miron, A.C., de Assis, R.L., Domingues, T.F., Aragão, L.E.O.C., Meir, P., Camargo, J.L., Manzi, A.O., Nagy, L., Mercado, L.M., Hartley, I.P. and Quesada, C.A. | Direct evidence for phosphorus limitation on Amazon forest productivity | 2022 | Nature Vol. 608(7923), pp. 558-562 |
article | DOI URL |
Abstract: The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change. | |||||
BibTeX:
@article{cunha_direct_2022, author = {Cunha, Hellen Fernanda Viana and Andersen, Kelly M. and Lugli, Laynara Figueiredo and Santana, Flavia Delgado and Aleixo, Izabela Fonseca and Moraes, Anna Martins and Garcia, Sabrina and Di Ponzio, Raffaello and Mendoza, Erick Oblitas and Brum, Bárbara and Rosa, Jéssica Schmeisk and Cordeiro, Amanda L. and Portela, Bruno Takeshi Tanaka and Ribeiro, Gyovanni and Coelho, Sara Deambrozi and de Souza, Sheila Trierveiler and Silva, Lara Siebert and Antonieto, Felipe and Pires, Maria and Salomão, Ana Cláudia and Miron, Ana Caroline and de Assis, Rafael L. and Domingues, Tomas F. and Aragão, Luiz E. O. C. and Meir, Patrick and Camargo, José Luis and Manzi, Antonio Ocimar and Nagy, Laszlo and Mercado, Lina M. and Hartley, Iain P. and Quesada, Carlos Alberto}, title = {Direct evidence for phosphorus limitation on Amazon forest productivity}, journal = {Nature}, year = {2022}, volume = {608}, number = {7923}, pages = {558--562}, url = {https://doi.org/10.1038/s41586-022-05085-2}, doi = {https://doi.org/10.1038/s41586-022-05085-2} } |
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Culf, A.D., Fisch, G., Malhi, Y., Costa, R.C., Nobre, A.D., Marques, A.D., Gash, J.H.C. and Grace, J. | Carbon dioxide measurements in the nocturnal boundary layer over Amazonian forest | 1999 | Hydrology and Earth System Sciences Vol. 3(1), pp. 39-53 |
article | URL |
Abstract: Measurements of carbon dioxide concentration, temperature and windspeed were made in the nocturnal boundary layer over a tropical forest near Manaus, Brazil using a tethered balloon system. The measurements were made up to a maximum height of 300 m on ten consecutive nights in November 1995. Simultaneous surface flux and in-canopy concentration measurements were made at the surface close to the site. The observation period included several different types of conditions. Generally strong windshear and relatively weak temperature gradients prevented the formation of a strong capping inversion to the nocturnal boundary layer. On some nights, however, the inversion was sufficiently strong that the CO2 concentration at 100 m above the surface exceeded 400 ppm. The concentration within the canopy was largely controlled by the presence of an inversion very close to the canopy surface. The temperature and wind profiles are contrasted with conditions in Rondonia, Brazil, where the windshear was found to be ural;er and higher carbon dioxide concentrations were observed in the early morning. The difference in carbon dioxide concentrations in the nocturnal boundary layer between dusk and dawn is used to estimate the regional nighttime flux of carbon dioxide. The value obtained generally exceeds the measured surface flux and sometimes exceeds the sum of the surface flux and the in-canopy storage made at the tower site. The reasons for the discrepency are not clear; either one of the methods is in error or the regional carbon dioxide budget differs significantly from the local budget measured at the tower site. | |||||
BibTeX:
@article{culf_carbon_1999, author = {Culf, A. D. and Fisch, G. and Malhi, Y. and Costa, R. C. and Nobre, A. D. and Marques, A. D. and Gash, J. H. C. and Grace, J.}, title = {Carbon dioxide measurements in the nocturnal boundary layer over Amazonian forest}, journal = {Hydrology and Earth System Sciences}, year = {1999}, volume = {3}, number = {1}, pages = {39--53}, url = {://WOS:000081370300005} } |
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Culf, A.D., Fisch, G., Lean, J. and Polcher, J. | A comparison of Amazonian climate data with general circulation model simulations | 1998 | Journal of Climate Vol. 11(11), pp. 2764-2773 |
article | DOI URL |
Abstract: Climate data from the Anglo-Brazilian Amazonian Climate Observation Study have been compared with the simulations of three general circulation models with prognostic cloud schemes. Monthly averages of net all wave radiation. incoming solar radiation, net longwave radiation, and precipitation obtained from automatic weather stations sited in three areas of Amazonia are compared with the output from the unified model of the Hadley Centre for Climate Prediction and Research, the operational forecasting model of the European Centre for Medium-Range Weather Forecasts (ECMWF), and the model of the Laboratoire dr Meteorologie Dynamique (LMD). The performance of the models is much improved when compared to comparisons of observations with the output from earlier, less sophisticated models. However. the Hadley Centre and LMD models tend to overpredict net and solar radiation, and the ECMWF model underpredicts net and solar radiation at two of the sites, but performs very well in Manaus. it is shown that the errors are mainly linked to the amount of cloud cover produced by the models. but also to the incoming clear sky solar radiation. | |||||
BibTeX:
@article{culf_comparison_1998, author = {Culf, A. D. and Fisch, G. and Lean, J. and Polcher, J.}, title = {A comparison of Amazonian climate data with general circulation model simulations}, journal = {Journal of Climate}, year = {1998}, volume = {11}, number = {11}, pages = {2764--2773}, url = {://WOS:000077171400003}, doi = {https://doi.org/10.1175/1520-0442(1998)011%3C2764:acoacd%3E2.0.co;2} } |
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Cuartas, L., Tomasella, J., Nobre, A., Nobre, C., Hodnett, M., Waterloo, M., Oliveira, S., von Randow, R., Trancoso, R. and Ferreira, M. | Distributed hydrological modeling of a micro-scale rainforest watershed in Amazonia: Model evaluation and advances in calibration using the new HAND terrain model [BibTeX] |
2012 | Jornal of Hydrology Vol. 462–463, pp. 15-27 |
article | |
BibTeX:
@article{cuartas_distributed_2012, author = {Cuartas, L.A. and Tomasella, J. and Nobre, A.D. and Nobre, C.A. and Hodnett, M.G. and Waterloo, M.J. and Oliveira, S.M. and von Randow, R.C. and Trancoso, R. and Ferreira, M.}, title = {Distributed hydrological modeling of a micro-scale rainforest watershed in Amazonia: Model evaluation and advances in calibration using the new HAND terrain model}, journal = {Jornal of Hydrology}, year = {2012}, volume = {462–463}, pages = {15--27} } |
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Cuartas, L.A., Tomasella, J., Nobre, A.D., Hodnett, M.G., Waterloo, M.J. and Munera, J.C. | Interception water-partitioning dynamics for a pristine rainforest in Central Amazonia: Marked differences between normal and dry years | 2007 | Agricultural and Forest Meteorology Vol. 145(1-2), pp. 69-83 |
article | DOI URL |
Abstract: In this study, we designed and built an automated system of collection and measurement of throughfall and stemflow, developing a new sampling methodology. Throughfall was measured by trough-type system of collectors, each collector with sampling area of 5 cm x 6 m, connected every six troughs to a large tipping bucket raingauge. Our throughfall measurement system covered a larger surface area than do most commonly used randomly relocated gauges, reducing the spatial variability. Temporal resolution was high (5 min), allowing the study of the short-term dynamics of the interception process. Stemflow was collected from 65 trees and also measured by large tipping bucket raingauges. Water vapor exchange at the forest-atmosphere interface was derived from eddy covariance data from a flux tower in the same area as the interception study. During the study period (November 2002-October 2004) a mild El Nino year developed and total annual rainfall was considerably lower than the average for the region. The interception loss in the year with normal rainfall was 13.3%, compared to 22.6% of gross precipitation in the dry year. The interception difference is explained by the comparison of mean intensity and duration of events in the normal year (8.77 mm/h and 1.88 h) versus the driest year (5.36 mm/h and 2.32 h). Interception loss for the whole period represented 16.5% of the gross rainfall, with throughfall 82.9% and stemflow 0.6%. We used the analytical Gash model to estimate the interception loss. The model succeeded in capturing the variability associated to the variability in the characteristics of precipitation. This is the first study to show the variability of interception in relation to rainfall (seasonally and between years). (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{cuartas_interception_2007, author = {Cuartas, Luz Adriana and Tomasella, Javier and Nobre, Antonio Donato and Hodnett, Martin G. and Waterloo, Maarten J. and Munera, Juan Camilo}, title = {Interception water-partitioning dynamics for a pristine rainforest in Central Amazonia: Marked differences between normal and dry years}, journal = {Agricultural and Forest Meteorology}, year = {2007}, volume = {145}, number = {1-2}, pages = {69--83}, url = {://WOS:000248322900005}, doi = {https://doi.org/10.1016/j.agrformet.2007.04.008} } |
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Cruvinel, E., Bustamante, M., Kozovits, A. and Zepp, R. | Soil emissions of NO, N2O and CO2 from croplands in the savanna region of central Brazil [BibTeX] |
2011 | Agriculture, Ecosystems & Environment Vol. 144, pp. 29-40 |
article | |
BibTeX:
@article{cruvinel_soil_2011, author = {Cruvinel, E.B.F. and Bustamante, M.M.C. and Kozovits, A.R. and Zepp, R.G.}, title = {Soil emissions of NO, N2O and CO2 from croplands in the savanna region of central Brazil}, journal = {Agriculture, Ecosystems & Environment}, year = {2011}, volume = {144}, pages = {29--40} } |
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Cristovam, B., Monteiro, A., Corvalán, C., Gurgel, H., Carvalho, M.S., Artaxo, P., Hacon, S. and Ragoni, V. | Mudanças climáticas e ambientais e seus efeitos na saúde: cenários e incertezas para o Brasil [BibTeX] |
2009 | Epidemiologia e Serviços de Saúde Vol. 18(3), pp. 285-304 |
article | |
BibTeX:
@article{cristovam_mudancas_2009, author = {Cristovam, B. and Monteiro, A.M.V. and Corvalán, C. and Gurgel, H.C. and Carvalho, M. S. and Artaxo, P. and Hacon, S.S. and Ragoni, V.}, title = {Mudanças climáticas e ambientais e seus efeitos na saúde: cenários e incertezas para o Brasil}, journal = {Epidemiologia e Serviços de Saúde}, year = {2009}, volume = {18}, number = {3}, pages = {285--304} } |
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Crill, P.M., Keller, M., Weitz, A., Grauel, B. and Veldkamp, E. | Intensive field measurements of nitrous oxide emissions from a tropical agricultural soil | 2000 | Global Biogeochemical Cycles Vol. 14(1), pp. 85-95 |
article | DOI URL |
Abstract: The amount of nitrous oxide (N2O) continues to increase in the atmosphere. Agricultural use of nitrogen fertilizers in the tropics is thought to be an important source of atmospheric N2O. High frequency, highly precise measurements of the N2O flux were made with an automated system deployed in N fertilized and unfertilized agricultural plots of papaya and corn in Costa Rica for an entire corn crop growth to harvest cycle. N2O fluxes were as high as 64 ng N-N2O cm(-2) h(-1) from fertilized versus 12 ng N-N2O cm(-2) h(-1) from unfertilized corn and 28 ng N-N2O cm(-2) h(-1) from fertilized versus 4.6 ng N-N2O cm(-2) h(-1) from unfertilized papaya. Fertilized corn released more N2O than fertilized papaya over the 125 days of the crop cycle, 1.83 kg N ha(-1) versus 1.37 kg N ha(-1). This represents a loss as N2O of 1.1 and 0.9% of the total N applied as ammonium nitrate to the corn and papaya, respectively. As has often been observed, N2O fluxes were highly variable. The fastest rates of emission were associated with fertilization and high soil moisture. A diurnal cycle in the fluxes was not evident probably due to the minimal day/night temperature fluctuations. Each chamber was measured between 509 and 523 times over the course of the experiment. This allows us to evaluate the effect on constructed mean fluxes of lowered sampling frequencies. Sampling each collar about once a day throughout the crop cycle (25% of the data set) could result in a calculated mean flux from any individual chamber that can vary by as much as 20% even though the calculated mean would probably be within 10% of the mean of the complete data set. The uncertainty increases very rapidly at lower sampling frequencies. For example, if only 10% of the data set were used which would be the equivalent of sampling every other day, a very high sampling frequency in terms of manual measurements, the calculated mean flux could vary by as much as 40% or more at any given site. | |||||
BibTeX:
@article{crill_intensive_2000, author = {Crill, P. M. and Keller, M. and Weitz, A. and Grauel, B. and Veldkamp, E.}, title = {Intensive field measurements of nitrous oxide emissions from a tropical agricultural soil}, journal = {Global Biogeochemical Cycles}, year = {2000}, volume = {14}, number = {1}, pages = {85--95}, url = {://WOS:000085808900008}, doi = {https://doi.org/10.1029/1999gb900088} } |
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Cramer, J.M., Mesquita, R.C.G. and Williamson, G.B. | Forest fragmentation differentially affects seed dispersal of large and small-seeded tropical trees | 2007 | Biological Conservation Vol. 137(3), pp. 415-423 |
article | DOI URL |
Abstract: The responses of plant-animal interactions to forest fragmentation can vary. We hypothesized that large-seeded plant species would be more susceptible to forest fragmentation than small-seeded species because large-seeded species rely on a few, extinction prone dispersers. We compared seed dispersal of the large-seeded, mammal dispersed Duckeodendron cestroides and the small-seeded, avian dispersed Bocageopsis multiflora. The number, percentage, distance, and distributions of dispersed seeds were all reduced in fragments for Duckeodendron but not for Bocageopsis. Other fragmention research in tropical communities supports this hypothesis through three lines of evidence: (1) Large-seeded plant species are more prone to extinction, (2) Fragmentation restricts or alters the movement of large animal dispersers more than small dispersers, and (3) Large and small-seeded species seem to be differentially linked to primary and secondary forest habitats. Therefore, small-seeded plants may be more resilient to forest fragmentation while large-seeded species may be more susceptible and should be a priority for conservation. (C) 2007 Elsevier Ltd. All rights reserved | |||||
BibTeX:
@article{cramer_forest_2007, author = {Cramer, Jennifer M. and Mesquita, Rita C. G. and Williamson, G. Bruce}, title = {Forest fragmentation differentially affects seed dispersal of large and small-seeded tropical trees}, journal = {Biological Conservation}, year = {2007}, volume = {137}, number = {3}, pages = {415--423}, url = {://WOS:000247775600010}, doi = {https://doi.org/10.1016/j.biocon.2007.02.019} } |
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Cox, P.M., Harris, P.P., Huntingford, C., Betts, R.A., Collins, M., Jones, C.D., Jupp, T.E., Marengo, J.A. and Nobre, C.A. | Increasing risk of Amazonian drought due to decreasing aerosol pollution | 2008 | Nature Vol. 453(7192), pp. 212-U7 |
article | DOI URL |
Abstract: The Amazon rainforest plays a crucial role in the climate system, helping to drive atmospheric circulations in the tropics by absorbing energy and recycling about half of the rainfall that falls on it. This region ( Amazonia) is also estimated to contain about one-tenth of the total carbon stored in land ecosystems, and to account for one-tenth of global, net primary productivity(1). The resilience of the forest to the combined pressures of deforestation and global warming is therefore of great concern(2), especially as some general circulation models ( GCMs) predict a severe drying of Amazonia in the twenty- first century(3-5). Here we analyse these climate projections with reference to the 2005 drought in western Amazonia, which was associated(6) with unusually warm North Atlantic sea surface temperatures ( SSTs). We show that reduction of dry-season ( July - October) rainfall in western Amazonia correlates well with an index of the north - south SST gradient across the equatorial Atlantic ( the 'Atlantic N - S gradient'). Our climate model is unusual among current GCMs in that it is able to reproduce this relationship and also the observed twentieth- century multidecadal variability in the Atlantic N - S gradient(7), provided that the effects of aerosols are included in the model(8). Simulations for the twenty- first century using the same model(3,8) show a strong tendency for the SST conditions associated with the 2005 drought to become much more common, owing to continuing reductions in reflective aerosol pollution in the Northern Hemisphere(9). | |||||
BibTeX:
@article{cox_increasing_2008, author = {Cox, Peter M. and Harris, Phil P. and Huntingford, Chris and Betts, Richard A. and Collins, Matthew and Jones, Chris D. and Jupp, Tim E. and Marengo, Jose A. and Nobre, Carlos A.}, title = {Increasing risk of Amazonian drought due to decreasing aerosol pollution}, journal = {Nature}, year = {2008}, volume = {453}, number = {7192}, pages = {212--U7}, note = {Edition: 2008/05/10}, url = {://WOS:000255592400037}, doi = {https://doi.org/10.1038/nature06960} } |
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Cox, P.M., Betts, R.A., Collins, M., Harris, P.P., Huntingford, C. and Jones, C.D. | Amazonian forest dieback under climate-carbon cycle projections for the 21st century | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 137-156 |
article | DOI URL |
Abstract: The first GCM climate change projections to include dynamic vegetation and an interactive carbon cycle produced a very significant amplification of global warming over the 21st century. Under the IS92a "business as usual" emissions scenario CO2 concentrations reached about 980 ppmv by 2100, which is about 280 ppmv higher than when these feedbacks were ignored. The major contribution to the increased CO2 arose from reductions in soil carbon because global warming is assumed to accelerate respiration. However, there was also a lesser contribution from an alarming loss of the Amazonian rainforest. This paper describes the phenomenon of Amazonian forest dieback under elevated CO2 in the Hadley Centre climate-carbon cycle model. | |||||
BibTeX:
@article{cox_amazonian_2004, author = {Cox, P. M. and Betts, R. A. and Collins, M. and Harris, P. P. and Huntingford, C. and Jones, C. D.}, title = {Amazonian forest dieback under climate-carbon cycle projections for the 21st century}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {137--156}, url = {://WOS:000222024700011 http://www.springerlink.com/content/5ya2xh872g25fglt/fulltext.pdf}, doi = {https://doi.org/10.1007/s00704-004-0049-4} } |
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Cowling, S.A., Betts, R.A., Cox, P.M., Ettwein, V.J., Jones, C.D., Maslin, M.A. and Spall, S.A. | Contrasting simulated past and future responses of the Amazonian forest to atmospheric change | 2004 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 359(1443), pp. 539-547 |
article | DOI URL |
Abstract: Modelling simulations of palaeoclimate and past vegetation form and function can contribute to global change research by constraining predictions of potential earth system responses to future warming, and by providing useful insights into the ecophysiological tolerances and threshold responses of plants to varying degrees of atmospheric change. We contrasted HadCM3LC simulations of Amazonian forest at the last glacial maximum (LGM; 21 kyr ago) and a Younger Dryas-like period (13-12 kyr ago) with predicted responses of future warming to provide estimates of the climatic limits under which the Amazon forest remains relatively stable. Our simulations indicate that despite lower atmospheric CO(2) concentrations and increased aridity during the LGM, Amazonia remains mostly forested, and that the cooling climate of the Younger Dryas-like period in fact causes a trend toward increased above-ground carbon balance relative to today. The vegetation feedbacks responsible for maintaining forest integrity in past climates (i.e. decreased evapotranspiration and reduced plant respiration) cannot be maintained into the future. Although elevated atmospheric CO(2) contributes to a positive enhancement of plant carbon and water balance, decreased stomatal conductance and increased plant and soil respiration cause a positive feedback that amplifies localized drying and climate warming. We speculate that the Amazonian forest is currently near its critical resiliency threshold, and that even minor climate warming may be sufficient to promote deleterious feedbacks on forest integrity. | |||||
BibTeX:
@article{cowling_contrasting_2004, author = {Cowling, S. A. and Betts, R. A. and Cox, P. M. and Ettwein, V. J. and Jones, C. D. and Maslin, M. A. and Spall, S. A.}, title = {Contrasting simulated past and future responses of the Amazonian forest to atmospheric change}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {539--547}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100016}, doi = {https://doi.org/10.1098/rstb.2003.1427} } |
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Couto-Santos, F.R., Luizão, F.J. and Carneiro Filho, A. | The influence of the conservation status and changes in the rainfall regime on forest-savanna mosaic dynamics in Northern Brazilian Amazonia [BibTeX] |
2014 | Acta Amazonica Vol. 44(2), pp. 197 - 206 |
article | |
BibTeX:
@article{couto-santos_influence_2014, author = {Couto-Santos, Fabiana R. and Luizão, Flávio J. and Carneiro Filho, Arnaldo}, title = {The influence of the conservation status and changes in the rainfall regime on forest-savanna mosaic dynamics in Northern Brazilian Amazonia}, journal = {Acta Amazonica}, year = {2014}, volume = {44}, number = {2}, pages = {197 -- 206} } |
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Couto-Santos, F. and Luizão, F. | Fine litter accumulation in Central Amazonian Tropical Rainforest canopy [BibTeX] |
2010 | Acta Amazonica Vol. 40(4), pp. 781- 786 |
article | |
BibTeX:
@article{couto-santos_fine_2010, author = {Couto-Santos, F.R. and Luizão, F.J.}, title = {Fine litter accumulation in Central Amazonian Tropical Rainforest canopy}, journal = {Acta Amazonica}, year = {2010}, volume = {40}, number = {4}, pages = {781-- 786} } |
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Couto, E.G. and Oliveira, V. | The Soil Diversity of the Pantanal [BibTeX] |
2011 | The Pantanal: Ecology, biodiversity and sustainable management of a large neotropical seasonal wetland, pp. 71-102 | incollection | |
BibTeX:
@incollection{pensoft_soil_2011, author = {Couto, E. G. and Oliveira, V.A.T.}, title = {The Soil Diversity of the Pantanal}, booktitle = {The Pantanal: Ecology, biodiversity and sustainable management of a large neotropical seasonal wetland}, year = {2011}, pages = {71--102} } |
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Costa, W.M.d. | Ordenamento Territorial e Amazônia: Vinte Anos de Experiências de Zoneamento Ecológico e Econômico [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 241-275 |
incollection | |
BibTeX:
@incollection{batistella_ordenamento_2008, author = {Costa, Wanderley Messias da}, title = {Ordenamento Territorial e Amazônia: Vinte Anos de Experiências de Zoneamento Ecológico e Econômico}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {241--275}, note = {Section: 3} } |
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Costa, F., J.R.P., F., Souza, G., Nobre, S.S. and R.F., C.A. | Variabilidade diária da precipitação em regiões de floresta e pastagem na Amazônia [BibTeX] |
1998 | Acta Amazonica Vol. 28(4), pp. 395-408 |
article | |
BibTeX:
@article{costa_variabilidade_1998, author = {Costa, Feitosa, J.R.P., Fisch, G., Souza, S.S., Nobre, C.A., R.F.}, title = {Variabilidade diária da precipitação em regiões de floresta e pastagem na Amazônia}, journal = {Acta Amazonica}, year = {1998}, volume = {28}, number = {4}, pages = {395--408} } |
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Costa, J.V., Souza, R.A.F., Andreoli R, V, Cartaxo E ., P. and Silva | Monitoring of methane on dams of hydroelectrics of the Amazon basin from the AQUA satellite information [BibTeX] |
2014 | Journal of Hyperspectral Remote Sensing Vol. 4, pp. 19-30 |
article | |
BibTeX:
@article{costa_monitoring_2014, author = {Costa, J. V. ; Souza, R. A. F. ; Andreoli R V ; Cartaxo E ., P.; Silva}, title = {Monitoring of methane on dams of hydroelectrics of the Amazon basin from the AQUA satellite information}, journal = {Journal of Hyperspectral Remote Sensing}, year = {2014}, volume = {4}, pages = {19--30} } |
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Costa, M.P.F., Niemann, O., Novo, E. and Ahern, F. | Biophysical properties and mapping of aquatic vegetation during the hydrological cycle of the Amazon floodplain using JERS-1 and Radarsat | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1401-1426 |
article | DOI URL |
Abstract: Field measurements were combined with Synthetic Aperture Radar (SAR) images to evaluate the use of radar for estimating biomass changes and mapping of aquatic vegetation in the lower Amazon. Field campaigns were conducted concomitant to the acquisition of Radarsat and JERS-1 images at five different stages of the hydrological cycle. The temporal variability of the SAR data for aquatic vegetation shows a dynamic range of 5 dB, however this is due dominantly to the significant differences (ptextless0.05) between the low water season when vegetation is small and just emerging and other seasons when vegetation is fully developed. The spatial variability of the above-water biomass is detectable with radar data. Significant correlation (ptextless0.05) exist between backscattering coefficients and both above-water dry biomass and height of the plants. The logarithmic relationship between backscattering coefficients and biomass suggests that (1) at low biomass, high transmissivity of the microwave radiation through the vegetation canopy occurs and the backscattering is a result of quasi-specular reflection of both C and L bands and a minor contribution of canopy volume scattering from C band; (2) at intermediate levels of biomass, moderate changes in backscattering values occur and the saturation point of backscattering is reached; and (3) at high biomass, the transmissivity of C and L band radiation is equally attenuated and backscattering approaches similar values for both. A combination of Radarsat and JERS-1 images from high and low water periods were classified using a segmentation algorithm and had an accuracy higher than 97% for vegetated areas of the floodplain. Although further research is needed to better understand the saturation points for Radarsat and JERS-1 data, these findings clearly show that C and L bands can accurately map aquatic vegetation of the Amazon floodplain. | |||||
BibTeX:
@article{costa_biophysical_2002, author = {Costa, M. P. F. and Niemann, O. and Novo, E. and Ahern, F.}, title = {Biophysical properties and mapping of aquatic vegetation during the hydrological cycle of the Amazon floodplain using JERS-1 and Radarsat}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1401--1426}, url = {://WOS:000174661900011}, doi = {https://doi.org/10.1080/01431160110092957} } |
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Costa, M.P.F. | Use of SAR satellites for mapping zonation of vegetation communities in the Amazon floodplain | 2004 | International Journal of Remote Sensing Vol. 25(10), pp. 1817-1835 |
article | DOI URL |
Abstract: Radarsat and JERS-1 imagery were used for mapping zonation of vegetation communities in the Amazon floodplain. Imagery analysis indicates that at periods of minimum water level the backscattering values of both C and L bands are the lowest and as the water level rises, so do the backscattering values. JERS-1 imagery exhibits a larger dynamic range of backscattering in response to the ground cover for the two extremes of water level (10 dB) compared to Radarsat imagery. The backscattering differences from different ground cover allowed the use of a region-based classification that produced seasonal maps with accuracies higher than 95% for vegetated areas of the floodplain. These seasonal maps were used to estimate the spatial distribution and time of inundation and the vegetation cover of the floodplain. It was possible to determine that semi-aquatic vegetation, tree-like aquatic plants, and shrub-like trees colonize regions flooded for at least 300 days year(-1) . Secondary colonizers, such as tall well-developed floodplain forest, cover regions flooded for approximately 150 days year(-1) , and floodplain climax forest colonize regions inundated for approximately 60 days year(-1) . | |||||
BibTeX:
@article{costa_use_2004, author = {Costa, M. P. F.}, title = {Use of SAR satellites for mapping zonation of vegetation communities in the Amazon floodplain}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {10}, pages = {1817--1835}, url = {://WOS:000220718500003}, doi = {https://doi.org/10.1080/0143116031000116985} } |
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Costa, M.H., Yanagi, S.N.M., Souza, P.J.O.P., Ribeiro, A. and Rocha, E.J.P. | Climate change in Amazonia caused by soybean cropland expansion, as compared to caused by pastureland expansion | 2007 | Geophysical Research Letters Vol. 34(7) |
article | DOI URL |
Abstract: In the last two decades, the strong increase of pasturelands over former rainforest areas has raised concerns about the climate change that such change in land cover might cause. In recent years, though, expansion of soybean croplands has been increasingly important in the agricultural growth in Amazonia. In this paper we use the climate model CCM3 to investigate whether the climate change due to soybean expansion in Amazonia would be any different from the one due to pastureland expansion. The land component of the model has been updated with new findings from the Large-Scale Biosphere Experiment in Amazonia (LBA), and a new soybean micrometeorological experiment in Amazonia. Results show that the decrease in precipitation after a soybean extension is significantly higher when compared to the change after a pastureland extension, a consequence of the very high albedo of the soybean. | |||||
BibTeX:
@article{costa_climate_2007, author = {Costa, Marcos H. and Yanagi, Silvia N. M. and Souza, Paulo J. O. P. and Ribeiro, Aristides and Rocha, Edson J. P.}, title = {Climate change in Amazonia caused by soybean cropland expansion, as compared to caused by pastureland expansion}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {7}, url = {://WOS:000245726000005 http://www.agu.org/pubs/crossref/2007/2007GL029271.shtml}, doi = {https://doi.org/10.1029/2007gl029271} } |
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Costa, M. and Yanagi, S. | Effects of Amazon deforestation on the regional climate – Historical perspective, current and future research [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 200-211 |
article | |
BibTeX:
@article{costa_effects_2006, author = {Costa, M.H. and Yanagi, S.N.M.}, title = {Effects of Amazon deforestation on the regional climate – Historical perspective, current and future research}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {200--211} } |
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Costa, M.H., Souza, J.D.C. and Ribeiro, A. | Comments on "The regional evapotranspiration of the Amazon'' [BibTeX] |
2004 | Journal of Hydrometeorology Vol. 5(6), pp. 1279-1280 |
article | DOI URL |
BibTeX:
@article{costa_comments_2004, author = {Costa, M. H. and Souza, J. D. C. and Ribeiro, A.}, title = {Comments on "The regional evapotranspiration of the Amazon''}, journal = {Journal of Hydrometeorology}, year = {2004}, volume = {5}, number = {6}, pages = {1279--1280}, url = {://WOS:000226184000020}, doi = {https://doi.org/10.1175/jhm-393.1} } |
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Costa, M.H. and Pires, G.F. | Effects of Amazon and Central Brazil deforestation scenarios on the duration of the dry season in the arc of deforestation | 2010 | International Journal of Climatology Vol. 30(13), pp. 1970-1979 |
article | DOI URL |
Abstract: Climate change predictions tied to Amazon deforestation scenarios are increasingly being used by government and non-government organisations for near-future planning applications. Despite incorporating a wide range of biophysical variables, these models neglect future scenarios of land use for adjoining regions, such as the Central Brazil Cerrado, which has been deforested by more than 50%. In this study, we investigate the impact of different Amazon and Central Brazil deforestation scenarios on the rainfall regime of the 'arc-of-deforestation' in Amazonia. We demonstrate that both Amazon and Cerrado deforestation contribute to an increase of the duration of the dry season in this region. Combining the effects of both scenarios, the dry season may increase from 5 months to 6 months, which may change the biosphere-atmosphere equilibrium in this region. This study demonstrates that the assessment of future Cerrado land use scenarios is also necessary to understand the future climate and ecosystem health of Amazonia. Copyright (C) 2009 Royal Meteorological Society | |||||
BibTeX:
@article{costa_effects_2010, author = {Costa, Marcos Heil and Pires, Gabrielle Ferreira}, title = {Effects of Amazon and Central Brazil deforestation scenarios on the duration of the dry season in the arc of deforestation}, journal = {International Journal of Climatology}, year = {2010}, volume = {30}, number = {13}, pages = {1970--1979}, url = {://WOS:000284211300007}, doi = {https://doi.org/10.1002/joc.2048} } |
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Costa, M.H., Oliveira, C.H.C., Andrade, R.G., Bustamante, T.R., Silva, F.A. and Coe, M.T. | A macroscale hydrological data set of river flow routing parameters for the Amazon Basin | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] Continental-scale hydrologic routing models, also known as macrohydrological routing models, have evolved considerably in the past few years. As the models have become more sophisticated, they have represented a variety of new processes and expanded their data requirements-either as input data or as validation for the model output. This paper presents a new data set of large-scale hydrological river flow routing parameters for the Amazon and Tocantins basins. Part of this data set was required by the development of the continental-scale hydrological routing model HYDRA and its application to the Amazon Basin. HYDRA represents phenomenalike floods, backwater effects, and seasonal hydrograph much more realistically than the previous generation of macrohydrological routing models. The data set contains data on (1) river network at 5-min ( 9 km) resolution, (2) time series of monthly means of river discharge and river stage for 122 fluviometric stations spread throughout the basin, (3) sinuosity of each of the main rivers measured at 111 river sections in the basin, and (4) depth to the water table and transmissivity of the aquifer derived from measurements taken at 81 points throughout the basin. | |||||
BibTeX:
@article{costa_macroscale_2002, author = {Costa, M. H. and Oliveira, C. H. C. and Andrade, R. G. and Bustamante, T. R. and Silva, F. A. and Coe, M. T.}, title = {A macroscale hydrological data set of river flow routing parameters for the Amazon Basin}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180336500004}, doi = {https://doi.org/10.1029/2000jd000309} } |
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Costa, M.H. and Foley, J.A. | Combined effects of deforestation and doubled atmospheric CO2 concentrations on the climate of Amazonia | 2000 | Journal of Climate Vol. 13(1), pp. 18-34 |
article | DOI URL |
Abstract: It is generally expected that the Amazon basin will experience at least two major environmental changes during the next few decades and centuries: 1) increasing areas of forest will be converted to pasture and cropland, and 2) concentrations of atmospheric CO2 will continue to rise. In this study, the authors use the National Center for Atmospheric Research GENESIS atmospheric general circulation model, coupled to the integrated Biosphere Simulator, to determine the combined effects of large-scale deforestation and increased CO2 concentrations (including both physiological and radiative effects) on Amazonian climate. In these simulations, deforestation decreases basin-average precipitation by 0.73 mm day(-1) over the basin, as it consequence of the general reduction in vertical motion above the deforested area (although there are some small regions with increased vertical motion). The overall effect of doubled CO2 concentrations in Amazonia is an increase in basin-average precipitation of 0.28 mm day(-1). The combined effect of deforestation and doubled CO2, including the interactions among the processes, is a decrease in the basin-average precipitation of 0.42 mm day(-1). While the effects of deforestation and increasing CO2 concentrations on precipitation tend to counteract one another. both processes work to warm the Amazon basin. The effect of deforestation and increasing CO2 concentrations both tend to increase surface temperature, mainly because of decreases in evapotranspiration and the radiative effect of CO2. The combined effect of deforestation and doubled CO2, including the interactions among the processes, increases the basin-average temperature by roughly 3.5 degrees C. | |||||
BibTeX:
@article{costa_combined_2000, author = {Costa, M. H. and Foley, J. A.}, title = {Combined effects of deforestation and doubled atmospheric CO2 concentrations on the climate of Amazonia}, journal = {Journal of Climate}, year = {2000}, volume = {13}, number = {1}, pages = {18--34}, url = {://WOS:000084708800002 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282000%29013%3C0018%3ACEODAD%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0442(2000)013%3C0018:ceodad%3E2.0.co;2} } |
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Costa, M.H. and Foley, J.A. | Trends in the hydrologic cycle of the Amazon basin | 1999 | Journal of Geophysical Research-Atmospheres Vol. 104(D12), pp. 14189-14198 |
article | DOI URL |
Abstract: Although previous studies have considered the long-term variability of precipitation and river discharge in the Amazon basin, other components of the hydrologic cycle, such as evapotranspiration and the transport of water vapor, have not received the same attention. This study examines the 20-year variability of the full hydrologic budget of the Amazon basin, using a 1976-1996 time series from the National Centers for Environmental Protection/National Center for Atmospheric Research reanalyzed meteorological data set. Within this 20-year record, there is a statistically significant decreasing trend in the atmospheric transport of water vapor both into and out of the Amazon basin. This trend is associated with a general relaxation of the southeasterly trade winds, a weakening of the east-to-west pressure gradient, and a warming of the sea surface temperatures in the equatorial South Atlantic region. While the atmospheric transport of water vapor through the Amazon basin has decreased, the internal recycling of precipitation within the basin increased and basin-wide precipitation, evapotranspiration, and runoff have remained nearly constant, Even though basin-average precipitation and runoff have remained fairly stable, other components of the Amazon basin's hydrologic cycle have been altered significantly by large-scale changes in atmospheric circulation. | |||||
BibTeX:
@article{costa_trends_1999, author = {Costa, M. H. and Foley, J. A.}, title = {Trends in the hydrologic cycle of the Amazon basin}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1999}, volume = {104}, number = {D12}, pages = {14189--14198}, url = {://WOS:000081188000001}, doi = {https://doi.org/10.1029/1998jd200126} } |
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Costa, M.H., Coe, M.T. and Guyot, J.L. | Effects of Climatic Variability and Deforestation on Surface Water Regimes [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 543-554 |
incollection | |
BibTeX:
@incollection{m_keller_effects_2009-1, author = {Costa, Marcos Heil and Coe, Michael T. and Guyot, Jean Loup}, title = {Effects of Climatic Variability and Deforestation on Surface Water Regimes}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {543--554} } |
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Costa, M.H., Botta, A. and Cardille, J.A. | Effects of large-scale changes in land cover on the discharge of the Tocantins River, Southeastern Amazonia | 2003 | Journal of Hydrology Vol. 283(1-4), pp. 206-217 |
article | DOI URL |
Abstract: Studies that relate changes in land cover with changes in river discharge at the small scale (textless 1 km(2)) are abundant. These studies generally indicate that deforestation causes an increase in the annual mean discharge. However, previous studies that evaluated the effects of changes in land cover in larger river basins (textgreater 100 km(2)) usually have not found similar relationships. Here we analyse a 50-year long time series of discharge of a tropical river, the Tocantins River at Porto Nacional (175,360 km(2)), as well as precipitation over this drainage area, during a period where substantial changes in land cover occurred in the basin (1949-1998). Based on agricultural census data, we estimate that, in 1960, about 30% of the basin was used for agriculture. Previous work indicates that by 1995, agriculture had increased substantially, with about 49% of the basin land used as cropland and pastures. Initially, we compare one period with little changes in land cover (period 1-1949-1968) with another with more intense changes in land cover (period 2-1979-1998). Our analysis indicates that, while precipitation over the basin is not statistically different between period 1 and period 2 (alpha = 0.05), annual mean discharge in period 2 is 24% greater than in period 1 (P textless 0.02), and the high-flow season discharge is greater by 28% (P textless 0.01). Further analyses present additional evidence that the change in vegetation cover altered the hydrological response of this region. As the pressure for changes in land cover in that region continue to increase, one can expect important further changes in the hydrological regime of the Tocantins River. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{costa_effects_2003, author = {Costa, M. H. and Botta, A. and Cardille, J. A.}, title = {Effects of large-scale changes in land cover on the discharge of the Tocantins River, Southeastern Amazonia}, journal = {Journal of Hydrology}, year = {2003}, volume = {283}, number = {1-4}, pages = {206--217}, url = {://WOS:000186726100012}, doi = {https://doi.org/10.1016/s0022-1694(03)00267-1} } |
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Costa, M.H., Biajoli, M.C., Sanches, L., Malhado, A.C.M., Hutyra, L.R., da Rocha, H.R., Aguiar, R.G. and de Araujo, A.C. | Atmospheric versus vegetation controls of Amazonian tropical rain forest evapotranspiration: Are the wet and seasonally dry rain forests any different? | 2010 | Journal of Geophysical Research-Biogeosciences Vol. 115(G4) |
article | DOI URL |
Abstract: This study analyzes evapotranspiration data for three wet and two seasonally dry rain forest sites in Amazonia. The main environmental (net radiation, vapor pressure deficit, and aerodynamic conductance) and vegetation (surface conductance) controls of evapotranspiration are also assessed. Our research supports earlier studies that demonstrate that evapotranspiration in the dry season is higher than that in the wet season and that surface net radiation is the main controller of evapotranspiration in wet equatorial sites. However, our analyses also indicate that there are different factors controlling the seasonality of evapotranspiration in wet equatorial rain forest sites and southern seasonally dry rain forests. While the seasonality of evapotranspiration in wet equatorial forests is driven solely by environmental factors, in seasonally dry forests, it is also biotically controlled with the surface conductance varying between seasons by a factor of approximately 2. The identification of these different drivers of evapotranspiration is a major step forward in our understanding of the water dynamics of tropical forests and has significant implications for the future development of vegetation-atmosphere models and land use and conservation planning in the region. | |||||
BibTeX:
@article{costa_atmospheric_2010, author = {Costa, Marcos H. and Biajoli, Marcia C. and Sanches, Luciana and Malhado, Ana C. M. and Hutyra, Lucy R. and da Rocha, Humberto R. and Aguiar, Renata G. and de Araujo, Alessandro C.}, title = {Atmospheric versus vegetation controls of Amazonian tropical rain forest evapotranspiration: Are the wet and seasonally dry rain forests any different?}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2010}, volume = {115}, number = {G4}, url = {://WOS:000284220800001 http://www.agu.org/pubs/crossref/2010/2009JG001179.shtml}, doi = {https://doi.org/10.1029/2009jg001179} } |
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Costa, M.H. | The data-model intercomparison project for the large-scale biosphere–atmosphere experiment in Amazonia [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183(15 December 2013), pp. 109-110 |
article | |
BibTeX:
@article{costa_data-model_2013, author = {Costa, Marcos Heil}, title = {The data-model intercomparison project for the large-scale biosphere–atmosphere experiment in Amazonia}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, number = {15 December 2013}, pages = {109--110} } |
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Costa, N., Senna, E.L., M.C.A., I. and H.M.A., M. | Estado-da-arte da simulação da taxa de fixação de carbono de Ecossistemas Tropicais [BibTeX] |
2009 | Revista Brasileira de Meteorologia Vol. 24(2), pp. 179-187 |
article | |
BibTeX:
@article{costa_estado-da-arte_2009, author = {Costa, Nunes, E.L., Senna, M.C.A., Imbuzeiro, H.M.A., M.H.}, title = {Estado-da-arte da simulação da taxa de fixação de carbono de Ecossistemas Tropicais}, journal = {Revista Brasileira de Meteorologia}, year = {2009}, volume = {24}, number = {2}, pages = {179--187} } |
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Costa, M. | Uso de imagens de radar para o cálculo da produção primária de plantas aquáticas nas várzeas da Amazônia [BibTeX] |
2005 | Acta Amazonica Vol. 35(2), pp. 145-154 |
article | |
BibTeX:
@article{costa_uso_2005, author = {Costa, M.}, title = {Uso de imagens de radar para o cálculo da produção primária de plantas aquáticas nas várzeas da Amazônia}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, number = {2}, pages = {145--154} } |
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Costa, M. | Estimate of net primary productivity of aquatic vegetation of the Amazon floodplain using Radarsat and JERS-1 | 2005 | International Journal of Remote Sensing Vol. 26(20), pp. 4527-4536 |
article | DOI URL |
Abstract: Synthetic aperture radar images, combined with field measurements, were used to estimate net primary productivity (NPP) of aquatic vegetation in the lower Amazon. Input data for a NPP model are (i) the total biomass of aquatic vegetation, determined by radar imagery and field measurements and (ii) the area occupied by aquatic vegetation, determined from radar imagery. After correction for monthly biomass losses, the NPP of one growth cycle of aquatic vegetation was calculated in the image domain. The total net primary productivity of Hymenachne amplexicaules, the dominant aquatic vegetation in the area, was on average 19 x 10(11) g C yr(-1) for the entire area. Spatially, lower values of produced organic carbon (textless 900gCm(-2)yr(-1)) are confined to regions where the plants developed only in the beginning of the rising phase of the hydrological cycle. In general, values are higher (textgreater5000 g Cm-2 yr(-1)) in areas closer to the Amazon River where the availability and influence of nutrient-rich water is greater. | |||||
BibTeX:
@article{costa_estimate_2005, author = {Costa, M.}, title = {Estimate of net primary productivity of aquatic vegetation of the Amazon floodplain using Radarsat and JERS-1}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {20}, pages = {4527--4536}, url = {://WOS:000233909500009}, doi = {https://doi.org/10.1080/01431160500213433} } |
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Costa, J., Mota, A., Tapia-Coral S., J.R. and Soares | Ações integradas em busca da sustentabilidade no Assentamento Tarumã-Mirim, zona rural de Manaus (AM) [BibTeX] |
2012 | Revista Brasileira de Agroecologia Vol. 7, pp. 14-24 |
article | |
BibTeX:
@article{costa_coes_2012, author = {Costa, J.E.C. ; Mota, A.M. ; Tapia-Coral, S., Joanne Regis; Soares}, title = {Ações integradas em busca da sustentabilidade no Assentamento Tarumã-Mirim, zona rural de Manaus (AM)}, journal = {Revista Brasileira de Agroecologia}, year = {2012}, volume = {7}, pages = {14--24} } |
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Costa, J.L.S. and Sá, L.D.d.A. | Variabilidade em escala da energia cinética turbulenta acima de floresta na amazônia ocidental [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 510 - 512 |
article | |
BibTeX:
@article{costa_variabilidade_2013, author = {Costa, Jorge Luiz Soares and Sá, Leonardo Deane de Abreu}, title = {Variabilidade em escala da energia cinética turbulenta acima de floresta na amazônia ocidental}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {510 -- 512} } |
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Costa, F.d.A. | Heterogeneidade Estrutural e Trajetórias Tecnológicas na Produção Rural da Amazônia: Delineamentos para Orientar Políticas de Desenvolvimento [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 137-180 |
incollection | |
BibTeX:
@incollection{batistella_heterogeneidade_2008, author = {Costa, Francisco de Assis}, title = {Heterogeneidade Estrutural e Trajetórias Tecnológicas na Produção Rural da Amazônia: Delineamentos para Orientar Políticas de Desenvolvimento}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {137--180}, note = {Section: 2} } |
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Costa, A.C.d., Metcalfe, D.B., Doughty, C.E., Oliveira, A.A.d., Neto, G.F., Costa, M.C.d., Silva Junior, J.d.A., Aragão, L.E., Almeida, S., Galbraith, D.R., Rowland, L.M., Meir, P. and Malhi, Y. | Ecosystem respiration and net primary productivity after 8–10 years of experimental through-fall reduction in an eastern Amazon forest [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 7-24 |
article | |
BibTeX:
@article{costa_ecosystem_2014, author = {Costa, Antonio C.L. da and Metcalfe, Daniel B. and Doughty, Chris E. and Oliveira, Alexandre A.R. de and Neto, Guilherme F.C. and Costa, Mauricio C. da and Silva Junior, João de Athaydes and Aragão, Luiz E.O.C. and Almeida, Samuel and Galbraith, David R. and Rowland, Lucy M. and Meir, Patrick and Malhi, Yadvinder}, title = {Ecosystem respiration and net primary productivity after 8–10 years of experimental through-fall reduction in an eastern Amazon forest}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {7--24} } |
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Costa, A.C.L.d., Galbraith, D., Almeida, S., Tanaka Portela, B.T., da Costa, M., de Athaydes Silva Junior, J., Braga, A.P., de Goncalves, P.H.L., de Oliveira, A.A.R., Fisher, R., Phillips, O.L., Metcalfe, D.B., Levy, P. and Meir, P. | Effect of 7 yr of experimental drought on vegetation dynamics and biomass storage of an eastern Amazonian rainforest | 2010 | New Phytologist Vol. 187(3), pp. 579-591 |
article | DOI URL |
Abstract: PtextgreaterAt least one climate model predicts severe reductions of rainfall over Amazonia during this century. Long-term throughfall exclusion (TFE) experiments represent the best available means to investigate the resilience of the Amazon rainforest to such droughts. Results are presented from a 7 yr TFE study at Caxiuana National Forest, eastern Amazonia. We focus on the impacts of the drought on tree mortality, wood production and above-ground biomass. Tree mortality in the TFE plot over the experimental period was 2.5% yr-1, compared with 1.25% yr-1 in a nearby control plot experiencing normal rainfall. Differences in stem mortality between plots were greatest in the largest (textgreater 40 cm diameter at breast height (dbh)) size class (4.1% yr-1 in the TFE and 1.4% yr-1 in the control). Wood production in the TFE plot was c. 30% lower than in the control plot. Together, these changes resulted in a loss of 37.8 +/- 2.0 Mg carbon (C) ha-1 in the TFE plot (2002-2008), compared with no change in the control. These results are remarkably consistent with those from another TFE (at Tapajos National Forest), suggesting that eastern Amazonian forests may respond to prolonged drought in a predictable manner. | |||||
BibTeX:
@article{costa_effect_2010, author = {Costa, Antonio Carlos Lola da and Galbraith, David and Almeida, Samuel and Tanaka Portela, Bruno Takeshi and da Costa, Mauricio and de Athaydes Silva Junior, Joao and Braga, Alan P. and de Goncalves, Paulo H. L. and de Oliveira, Alex A. R. and Fisher, Rosie and Phillips, Oliver L. and Metcalfe, Daniel B. and Levy, Peter and Meir, Patrick}, title = {Effect of 7 yr of experimental drought on vegetation dynamics and biomass storage of an eastern Amazonian rainforest}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {579--591}, note = {Edition: 2010/06/18}, url = {://WOS:000280122500007}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03309.x} } |
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Costa, A.C.L., Silva Júnior, J.A., Oliveira, A.A.R., Costa, C.L.R., Rowland, L.M., Meir, P., Cunha, A.C., Malhi, Y. and Rodrigues, H.J.B. | Variabilidade mensal e horária de elementos meteorológicos na área experimental do Projeto ESECAFLOR na Floresta Nacional de Caxiuanã, Pará, Brasil [BibTeX] |
2017 | Boletim do Museu Paraense Emílio Goeldi Ciências Naturais Vol. 11(3), pp. 365-375 |
article | |
BibTeX:
@article{costa_variabilidade_2017, author = {Costa, A. C. L. and Silva Júnior, J. A. and Oliveira, A. A. R. and Costa, C. L. R. and Rowland, L. M. and Meir, P. and Cunha, A. C. and Malhi, Y. and Rodrigues, H. J. B.}, title = {Variabilidade mensal e horária de elementos meteorológicos na área experimental do Projeto ESECAFLOR na Floresta Nacional de Caxiuanã, Pará, Brasil}, journal = {Boletim do Museu Paraense Emílio Goeldi Ciências Naturais}, year = {2017}, volume = {11}, number = {3}, pages = {365--375} } |
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Costa, A., Campos Filho, M., Santos, A. and Oliveira, J. | Características de cristais de gelo observados em um sistema de nuvens na amazônia durante o experimento TRMM-LBA [BibTeX] |
2012 | Revista Brasileira de Meteorologia Vol. 27(2), pp. 139 - 151 |
article | |
BibTeX:
@article{costa_caracteristicas_2012, author = {Costa, A.A. and Campos Filho, M.C. and Santos, A.C.S. and Oliveira, J.C.P.}, title = {Características de cristais de gelo observados em um sistema de nuvens na amazônia durante o experimento TRMM-LBA}, journal = {Revista Brasileira de Meteorologia}, year = {2012}, volume = {27}, number = {2}, pages = {139 -- 151} } |
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Costa, P. and A.A., T.M. | Aerossóis, nuvens e clima: resultados do experimento lba para o estudo de aerossóis e microfísica de nuvens [BibTeX] |
2009 | Revista Brasileira de Meteorologia Vol. 24(2), pp. 234-253 |
article | |
BibTeX:
@article{costa_aerossois_2009, author = {Costa, Pauliquevis, T.M., A.A.}, title = {Aerossóis, nuvens e clima: resultados do experimento lba para o estudo de aerossóis e microfísica de nuvens}, journal = {Revista Brasileira de Meteorologia}, year = {2009}, volume = {24}, number = {2}, pages = {234--253} } |
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Correia, F.W.S., Alvala, R.C.S. and Manzi, A.O. | Modeling the impacts of land cover change in Amazonia: a regional climate model (RCM) simulation study | 2008 | Theoretical and Applied Climatology Vol. 93(3-4), pp. 225-244 |
article | DOI URL |
Abstract: The numerical regional model (Eta) coupled with the Simplified Simple Biosphere Model (SSiB) was used to investigate the impact of land cover changes on the regional climate in Amazonia. Four 13-month integrations were performed for the following scenarios: (a) no deforestation, (b) current conditions, (c) deforestation predicted for 2033, and (d) large scale deforestation. All initial and prescribed boundary conditions were kept identical for all integrations, except the land cover changes. The results show that during the dry season the post-deforestation decrease in root depth plays an important role in the energy budget, since there is less soil moisture available for evapotranspiration. In all scenarios there was a significant increase in the surface temperature, from 2.0 degrees C in the first scenario, up to 2.8 degrees C in the last one. In both the scenarios (b) and (c), the downward component of the surface solar radiation decreased due to an increase in the cloud cover over the deforested areas, which contributed to a further reduction of the net radiation absorbed at the surface. The cloud mechanism, where an increase in albedo is balanced by an increase in downward solar radiation, was not detected in any of these scenarios. In scenarios (a), (b) and (c), a negative feedback mechanism was observed in the hydrological cycle, with greater amounts of moisture being carried to the deforested areas. The increase in moisture convergence was greater than the reduction in evapotranspiration for both scenarios (b) and (c). This result, and the meso-scale thermodynamic processes caused an increase in precipitation. A different situation was observed in the large-scale deforestation scenario (d): a local increase of moisture convergence was observed, but not sufficiently intense to generate an increase in precipitation; the local evapotranspiration decrease was dominant in this scenario. Therefore, the partial deforestation in Amazonia can actually lead to an increase in precipitation locally. However, if the deforestation increases, this condition becomes unsustainable, leading to drier conditions and, consequently, to reduced precipitation in the region. | |||||
BibTeX:
@article{correia_modeling_2008, author = {Correia, F. W. S. and Alvala, R. C. S. and Manzi, A. O.}, title = {Modeling the impacts of land cover change in Amazonia: a regional climate model (RCM) simulation study}, journal = {Theoretical and Applied Climatology}, year = {2008}, volume = {93}, number = {3-4}, pages = {225--244}, url = {://WOS:000258592900007}, doi = {https://doi.org/10.1007/s00704-007-0335-z} } |
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Correia, A., R.C.S., M. and F.W.S., A.O. | Impacto das Modificações da Cobertura Vegetal no Balanço de Água na Amazônia: Um estudo com Modelo de Circulação Geral da Atmosfera (MCGA) [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3), pp. 153-167 |
article | |
BibTeX:
@article{correia_impacto_2006, author = {Correia, Alvalá, R.C.S., Manzi, A.O., F.W.S.}, title = {Impacto das Modificações da Cobertura Vegetal no Balanço de Água na Amazônia: Um estudo com Modelo de Circulação Geral da Atmosfera (MCGA)}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3}, pages = {153--167} } |
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Correia, A., R.C.S., M., Gielow, A.O., Kubota, R. and F.W.S., P.Y. | Calibração do "simplified simple biosphere model - SSiB" para áreas de pastagem e floresta na Amazônia com dados do LBA [BibTeX] |
2005 | Acta Amazonica Vol. 35(2), pp. 273-288 |
article | |
BibTeX:
@article{correia_calibracao_2005, author = {Correia, Alvalá, R.C.S., Manzi, A.O., Gielow, R., Kubota, P.Y., F.W.S.}, title = {Calibração do "simplified simple biosphere model - SSiB" para áreas de pastagem e floresta na Amazônia com dados do LBA}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, number = {2}, pages = {273--288} } |
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Correia, A.L. and Catandi, P.B. | Deriving cloud microphysics from radiometric measurements in the Amazon Basin [BibTeX] |
2016 | Atmospheric Science Letters, pp. 708 | article | |
BibTeX:
@article{correia_deriving_2016, author = {Correia, A. L. and Catandi, P. B.}, title = {Deriving cloud microphysics from radiometric measurements in the Amazon Basin}, journal = {Atmospheric Science Letters}, year = {2016}, pages = {708} } |
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Correia, A., Freydier, R., Delmas, R.J., Simoes, J.C., Taupin, J.D., Dupre, B. and Artaxo, P. | Trace elements in South America aerosol during 20th century inferred from a Nevado Illimani ice core, Eastern Bolivian Andes (6350m asl) | 2003 | Atmospheric Chemistry and Physics Vol. 3, pp. 1337-1352 |
article | URL |
Abstract: A 137 m ice core drilled in 1999 from Eastern Bolivian Andes at the summit of Nevado Illimani (16degrees 37' S, 67 degrees 46' W, 6350 m asl) was analyzed at high temporal resolution, allowing a characterization of trace elements in Andean aerosol trapped in the ice during the 20th century. The upper 50 m of the ice core were dated by multi-proxy analysis of stable isotopes (delta(18)O and delta(2)H), (137)Cs and Ca(+2) content, electrical conductivity, and insoluble microparticle content, together with reference historical horizons from atmospheric nuclear tests and known volcanic eruptions. This 50 m section corresponds to a record of environmental variations spanning about 80 years from 1919 to 1999. It was cut in 744 sub-samples under laminar flow in a clean bench, which were analyzed by Ion Chromatography for major ionic concentration, by a particle counter for insoluble aerosol content, and by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for the concentration of 45 chemical species from Li to U. This paper focuses on results of trace element concentrations measured by ICP-MS. The high temporal resolution used in the analyses allowed classifying samples as belonging to dry or wet seasons. During wet season elemental concentrations are low and samples show high crustal enrichment factors. During dry seasons the situation is opposite, with high elemental concentrations and low crustal enrichments. For example, with salt lakes as main sources in the region, average Li concentration during the 20th century is 0.035 and 0.90 ng g(-1) for wet and dry seasons, respectively. Illimani average seasonal concentration ranges cover the spectrum of elemental concentration measurements at another Andean ice core site (Sajama) for most soil-related elements. Regional crustal dust load in the deposits was found to be overwhelming during dry season, obfuscating the contribution of biomass burning material. Marked temporal trends from the onset of 20th century to more recent years were identified for the concentrations of several trace species of anthropic origin, especially for Cu, As, Zn, Cd, Co, Ni and Cr. Among these elements, Cu shows average wet season crustal enrichment factors above 10(3), while the others range between 10(2) to about 5 x 10(2). P and K show moderate average wet season enrichment factors, suggesting an impact of natural biogenic emissions from the Amazon Basin. Pb has multiple anthropic sources in the region, from mining activities in the beginning of 20th century to automotive fuel after 1950s. From the large number of samples analyzed from Illimani, it was possible to derive an effective chemical characterization of the deposited background Andean soil dust aerosol during 20th century. | |||||
BibTeX:
@article{correia_trace_2003, author = {Correia, A. and Freydier, R. and Delmas, R. J. and Simoes, J. C. and Taupin, J. D. and Dupre, B. and Artaxo, P.}, title = {Trace elements in South America aerosol during 20th century inferred from a Nevado Illimani ice core, Eastern Bolivian Andes (6350m asl)}, journal = {Atmospheric Chemistry and Physics}, year = {2003}, volume = {3}, pages = {1337--1352}, url = {://WOS:000185256600001} } |
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Corrêa, L.A., Souza, R.A.F.d., Andreoli, R.V., Kayano Mary Toshie, P.B. and Candido | Estudo do Fenômeno da Ilha de Calor na Cidade de Manaus/AM: Um Estudo a Partir de Dados de Sensoriamento Remoto, Modelagem e Estações Meteorológicas [BibTeX] |
2016 | Revista Brasileira de Meteorologia Vol. 31, pp. 167-176 |
article | |
BibTeX:
@article{correa_estudo_2016, author = {Corrêa, Luiz Antonio ; Souza, Rodrigo Augusto Ferreira de ; Andreoli, Rita Valéria ; Kayano, Mary Toshie, Polari Batista ; Candido}, title = {Estudo do Fenômeno da Ilha de Calor na Cidade de Manaus/AM: Um Estudo a Partir de Dados de Sensoriamento Remoto, Modelagem e Estações Meteorológicas}, journal = {Revista Brasileira de Meteorologia}, year = {2016}, volume = {31}, pages = {167--176} } |
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Corrêa, P.B., Dias-Júnior, C.Q., Cava, D., Sörgel, M., Botía, S., Acevedo, O., Oliveira, P.E.S., Ocimar Manzi, A., Toledo Machado, L.A., dos Santos Martins, H., Tsokankunku, A., de Araújo, A.C., Lavric, J.V., Walter, D. and Mortarini, L. | A case study of a gravity wave induced by Amazon forest orography and low level jet generation | 2021 | Agricultural and Forest Meteorology Vol. 307, pp. 108457 |
article | DOI URL |
Abstract: We investigated the role of turbulent coherent structures (CS), gravity waves (GW) and low-level jet (LLJ) propagation in the flow dynamics of the Nocturnal Boundary Layer (NBL) within and above a forest canopy at the Amazon Tall Tower Observatory (ATTO), in Central Amazon. Seven levels of wind velocity and temperature measurements allowed the study of the flow structure below and above the surface layer. We analyzed one dynamically rich night in 2015, which includes three distinct periods. In the first one, the NBL is characterized by CS generated at the canopy top. In the second period, the change in wind direction triggers the onset of a orographic GW above the roughness sublayer. The wave, suppressing the propagation of CS, strongly influences the boundary layer structure, both above and below the canopy. In the third period, low turbulence intensity at the canopy top enables the development of a LLJ. As the jet shear layer propagates upward, it disrupts the wave oscillations, while LLJ dominates the flow dynamics. The wavelet analyses identified i) turbulent and non-turbulent structures with different length and time-scales; ii) coupling of the flow at different levels and the vertical propagation of turbulent and wave motions; and iii) the ability of turbulent and low frequency processes associated with the orographic GW to penetrate within the canopy. Further, scalar measurements of methane, carbon monoxide and carbon dioxide identified the LLJ nose as upward limit for how far scalars can be transported. | |||||
BibTeX:
@article{correa_case_2021, author = {Corrêa, Polari B. and Dias-Júnior, Cléo Q. and Cava, Daniela and Sörgel, Matthias and Botía, Santiago and Acevedo, Otávio and Oliveira, Pablo E. S. and Ocimar Manzi, Antônio and Toledo Machado, Luiz Augusto and dos Santos Martins, Hardiney and Tsokankunku, Anywhere and de Araújo, Alessandro C. and Lavric, Jost V. and Walter, David and Mortarini, Luca}, title = {A case study of a gravity wave induced by Amazon forest orography and low level jet generation}, journal = {Agricultural and Forest Meteorology}, year = {2021}, volume = {307}, pages = {108457}, url = {https://www.sciencedirect.com/science/article/pii/S0168192321001404}, doi = {https://doi.org/10.1016/j.agrformet.2021.108457} } |
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Coringa, E., Couto, E., Perez, X. and Torrado, P. | Atributos de solos hidromórficos no Pantanal Norte Matogrossense [BibTeX] |
2012 | Acta Amazonica Vol. 42(1), pp. 19 - 28 |
article | |
BibTeX:
@article{coringa_atributos_2012, author = {Coringa, E.A.O. and Couto, E.G. and Perez, X.L.O. and Torrado, P.V.}, title = {Atributos de solos hidromórficos no Pantanal Norte Matogrossense}, journal = {Acta Amazonica}, year = {2012}, volume = {42}, number = {1}, pages = {19 -- 28} } |
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Cordeiro, A.L., Norby, R.J., Andersen, K.M., Valverde-Barrantes, O., Fuchslueger, L., Oblitas, E., Hartley, I.P., Iversen, C.M., Gonçalves, N.B., Takeshi, B., Lapola, D.M. and Quesada, C.A. | Fine-root dynamics vary with soil depth and precipitation in a low-nutrient tropical forest in the Central Amazonia | 2020 | Plant-Environment Interactions Vol. 1(1), pp. 3-16 |
article | DOI URL |
Abstract: Why this research Matters A common assumption in tropical ecology is that root systems respond rapidly to climatic cues but that most of that response is limited to the uppermost layer of the soil, with relatively limited changes in deeper layers. However, this assumption has not been tested directly, preventing models from accurately predicting the response of tropical forests to environmental change. We measured seasonal dynamics of fine roots in an upper-slope plateau in Central Amazonia mature forest using minirhizotrons to 90 cm depth, which were calibrated with fine roots extracted from soil cores. Root productivity and mortality in surface soil layers were positively correlated with precipitation, whereas root standing length was greater during the dry periods at the deeper layers. Contrary to historical assumptions, a large fraction of fine-root standing biomass (46%) and productivity (41%) was found in soil layers deeper than 30 cm. Furthermore, root turnover decreased linearly with soil depth. Our findings demonstrate a relationship between fine-root dynamics and precipitation regimes in Central Amazonia. Our results also emphasize the importance of deeper roots for accurate estimates of primary productivity and the interaction between roots and carbon, water, and nutrients. | |||||
BibTeX:
@article{cordeiro_fine-root_2020, author = {Cordeiro, Amanda L. and Norby, Richard J. and Andersen, Kelly M. and Valverde-Barrantes, Oscar and Fuchslueger, Lucia and Oblitas, Erick and Hartley, Iain P. and Iversen, Colleen M. and Gonçalves, Nathan B. and Takeshi, Bruno and Lapola, David M. and Quesada, Carlos A.}, title = {Fine-root dynamics vary with soil depth and precipitation in a low-nutrient tropical forest in the Central Amazonia}, journal = {Plant-Environment Interactions}, year = {2020}, volume = {1}, number = {1}, pages = {3--16}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/pei3.10010}, doi = {https://doi.org/10.1002/pei3.10010} } |
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Confalonieri, U.E.C. | Saúde na Amazônia: um modelo conceitual para a análise de paisagens e doenças [BibTeX] |
2005 | Estudos Avançados Vol. 19(53) |
article | |
BibTeX:
@article{confalonieri_sauna_2005, author = {Confalonieri, Ulisses E. C.}, title = {Saúde na Amazônia: um modelo conceitual para a análise de paisagens e doenças}, journal = {Estudos Avançados}, year = {2005}, volume = {19}, number = {53} } |
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Conceição, R.L. and Ramos da Silva, R. | Insights of meso and micro-scale processes for the Caxiuana Forest region from high resolution simulation [BibTeX] |
2012 | Revista Brasileira de Meteorologia Vol. 27, pp. 287-294 |
article | |
BibTeX:
@article{conceicao_insights_2012, author = {Conceição, R. L. and Ramos da Silva, R.}, title = {Insights of meso and micro-scale processes for the Caxiuana Forest region from high resolution simulation}, journal = {Revista Brasileira de Meteorologia}, year = {2012}, volume = {27}, pages = {287--294} } |
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Conceição, A.S., Silva, L.D. and R. L., R.R. | Características das circulações locais na Floresta Nacional de Caxiuanã utilizando um modelo de alta resolução [BibTeX] |
2009 | Revista Ciência e Natura Vol. Edição Especial em Micrometeorologia, pp. 265-268 |
article | |
BibTeX:
@article{conceicao_caracteristicas_2009, author = {Conceição, Abreu Sá, L.D., Silva, R.R., R. L.}, title = {Características das circulações locais na Floresta Nacional de Caxiuanã utilizando um modelo de alta resolução}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Edição Especial em Micrometeorologia}, pages = {265--268} } |
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Collow, A.B.M., Miller, M.A. and Trabachino, L.C. | Cloudiness over the Amazon rainforest: Meteorology and thermodynamics [BibTeX] |
2016 | J. Geophys. Res.Atmos. Vol. 121, pp. 7990-8005 |
article | DOI |
BibTeX:
@article{collow_cloudiness_2016, author = {Collow, A. B. M. and Miller, M. A. and Trabachino, L. C.}, title = {Cloudiness over the Amazon rainforest: Meteorology and thermodynamics}, journal = {J. Geophys. Res.Atmos.}, year = {2016}, volume = {121}, pages = {7990--8005}, doi = {https://doi.org/10.1002/2016JD024848} } |
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Cohen, S., L.D.A., N., Gandu, D.S. and J.C.P., A.W. | Jatos de Baixos Níveis Acima da Floresta Amazônica em Caxiuanã [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3b), pp. 271-282 |
article | |
BibTeX:
@article{cohen_jatos_2006, author = {Cohen, Sa, L.D.A., Nogueira, D.S., Gandu, A.W., J.C.P.}, title = {Jatos de Baixos Níveis Acima da Floresta Amazônica em Caxiuanã}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3b}, pages = {271--282} } |
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Coe, M.T., Latrubesse, E.M., Ferreira, M.E. and Amsler, M.L. | The effects of deforestation and climate variability on the streamflow of the Araguaia River, Brazil | 2011 | Biogeochemistry Vol. 105(1-3), pp. 119-131 |
article | DOI URL |
Abstract: Deforestation changes the hydrological, geomorphological, and biochemical states of streams by decreasing evapotranspiration on the land surface and increasing runoff, river discharge, erosion and sediment fluxes from the land surface. Deforestation has removed about 55% of the native vegetation and significantly altered the hydrological and morphological characteristics of an 82,632 km(2) watershed of the Araguaia River in east-central Brazil. Observed discharge increased by 25% from the 1970s to the 1990s and computer simulations suggest that about 2/3 of the increase is from deforestation, the remaining 1/3 from climate variability. Changes of this scale are likely occurring throughout the 2,000,000 km(2) savannah region of central Brazil. | |||||
BibTeX:
@article{coe_effects_2011, author = {Coe, M. T. and Latrubesse, E. M. and Ferreira, M. E. and Amsler, M. L.}, title = {The effects of deforestation and climate variability on the streamflow of the Araguaia River, Brazil}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {119--131}, url = {://WOS:000294501100009 http://www.springerlink.com/content/w1ur82263r067755/fulltext.pdf}, doi = {https://doi.org/10.1007/s10533-011-9582-2} } |
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Coe, M.T., Costa, M.H. and Soares-Filhoc, B.S. | The influence of historical and potential future deforestation on the stream flow of the Amazon River - Land surface processes and atmospheric feedbacks | 2009 | Journal of Hydrology Vol. 369(1-2), pp. 165-174 |
article | DOI URL |
Abstract: In this study, results from two sets of numerical simulations are evaluated and presented: one with the land surface model IBIS forced with prescribed climate and another with the fully coupled atmospheric general circulation and land surface model CCM3-IBIS. The results illustrate the influence of historical and potential future deforestation on local evapotranspiration and discharge of the Amazon River system with and without atmospheric feedbacks and clarify a few important points about the impact of deforestation on the Amazon River. In the absence of a continental scale precipitation change, large-scale deforestation can have a significant impact on large river systems and appears to have already done so in the Tocantins and Araguaia Rivers, where discharge has increased 25% with little change in precipitation. However, with extensive deforestation (e.g. textgreater30% of the Amazon basin) atmospheric feedbacks, brought about by differences in the physical structure of the crops and pasture replacing natural vegetation, cause water balance changes of the same order of magnitude as the changes due to local land surface processes, but of opposite sign. Additionally, changes in the water balance caused by atmospheric feedbacks are not limited to those basins where deforestation has occurred but are spread unevenly throughout the entire Amazon by atmospheric circulation. As a result, changes to discharge and aquatic environments with future deforestation of the Amazon will likely be significant and a complex function of how much vegetation has been removed from that particular watershed and how much has been removed from the entire Amazon Basin. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{coe_influence_2009, author = {Coe, Michael T. and Costa, Marcos H. and Soares-Filhoc, Britaldo S.}, title = {The influence of historical and potential future deforestation on the stream flow of the Amazon River - Land surface processes and atmospheric feedbacks}, journal = {Journal of Hydrology}, year = {2009}, volume = {369}, number = {1-2}, pages = {165--174}, url = {://WOS:000266130600015}, doi = {https://doi.org/10.1016/j.jhydrol.2009.02.043} } |
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Coe, M.T., Costa, M.H. and Howard, E.A. | Simulating the surface waters of the Amazon River basin: impacts of new river geomorphic and flow parameterizations | 2008 | Hydrological Processes Vol. 22(14), pp. 2542-2553 |
article | DOI URL |
Abstract: This paper describes the impacts of new river geomorphic and flow parameterizations on the simulated surface waters dynamics of the Amazon River basin. Three major improvements to a hydrologic model are presented: (1) the river flow velocity equation is expanded to be dependent on river sinuosity and friction in addition to gradient forces; (2) equations defining the morphological characteristics of the river, such as river height, width and bankfull volume, are derived from 31622 measurements of river morphology and applied within the model; (3) 1 km resolution topographic data from the Shuttle Radar Topography Mission (SRTM) are used to provide physically based fractional flooding of grid cells from a statistical representation of sub-grid-scale floodplain morphology. The discharge and floodplain inundation of the Amazon River is simulated for the period 1968-1998, validated against observations, and compared with results from a previous version of the model. These modifications result in considerable improvement in the simulations of the hydrological features of the Amazon River system. The major impact is that the average wet-season flooded area on the Amazon mainstem for the period 1983-1988 is now within 5% of satellite-derived estimates of flooded area, whereas the previous model overestimates the flooded area by about 80%. The improvements are a consequence of the new empirical river geomorphologic functions and the SRTM topography. The new formulation of the flow velocity equation results in increased river velocity on the mainstem and major tributaries and a better correlation between the mean monthly simulated and observed discharge. Copyright (c) 2007 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{coe_simulating_2008, author = {Coe, Michael T. and Costa, Marcos H. and Howard, Erica A.}, title = {Simulating the surface waters of the Amazon River basin: impacts of new river geomorphic and flow parameterizations}, journal = {Hydrological Processes}, year = {2008}, volume = {22}, number = {14}, pages = {2542--2553}, url = {://WOS:000257954400014 http://onlinelibrary.wiley.com/store/10.1002/hyp.6850/asset/6850_ftp.pdf?v=1&t=h6hywkct&s=cce6c5bb679569dd9758dd638a19d70d5c84ad44}, doi = {https://doi.org/10.1002/hyp.6850} } |
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Coe, M.T., Costa, M.H., Botta, A. and Birkett, C. | Long-term simulations of discharge and floods in the Amazon Basin | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: A terrestrial ecosystem model (integrated biosphere simulator (IBIS)) and a hydrological routing algorithm (HYDRA) are used in conjunction with long time series climate data to simulate the river discharge and flooded area of the Amazon/Tocantins River basin over the last 60 years. Evaluating the results of this modeling exercise over the entire basin yields three major results: (1) Observations at 121 stations throughout the basin show that discharge is well simulated for most tributaries originating in Brazil. However, the discharge is consistently underestimated, by greater than 20%, for tributaries draining regions outside of Brazil and the main stem of the Amazon. The discharge underestimation is most likely a result of underestimated precipitation in the data set used as model input. (2) A new flooding algorithm within HYDRA captures the magnitude and timing of the river height and flooded area in relatively good agreement with observations, particularly downstream of the confluence of the Negro and Solimoes Rivers. (3) Climatic variability strongly impacts the hydrology of the basin. Specifically, we find that short (similar to3-4 years) and long (similar to28 years) modes of precipitation variability drive spatial and temporal variability in river discharge and flooded area throughout the Amazon/Tocantins River basins. | |||||
BibTeX:
@article{coe_long-term_2002, author = {Coe, M. T. and Costa, M. H. and Botta, A. and Birkett, C.}, title = {Long-term simulations of discharge and floods in the Amazon Basin}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180367300003 http://www.agu.org/journals/jd/jd0216/2001JD000740/2001JD000740.pdf}, doi = {https://doi.org/10.1029/2001jd000740} } |
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Coe, M.T. | Modeling terrestrial hydrological systems at the continental scale: Testing the accuracy of an atmospheric GCM | 2000 | Journal of Climate Vol. 13(4), pp. 686-704 |
article | DOI URL |
Abstract: A global hydrological routing algorithm (HYDRA) that simulates seasonal river discharge and changes in surface water level on a spatial resolution of 5' long x 5' lat is presented. The model is based an previous work by M. T. Coe and incorporates major improvements from that work including 1) the ability to simulate monthly and seasonal variations in discharge and lake and wetland level, and 2) direct representation of man-made dams and reservoirs. HYDRA requires as input daily or monthly mean averages of runoff, precipitation, and evaporation either from GCM output or observations. As an example of the utility of HYDRA in evaluating GCM simulations, the model is forced with monthly mean estimates of runoff from the National Centers for Environmental Prediction (NCEP) reanalysis dataset. The simulated river discharge clearly shows that although the NCEP runoff captures the large-scale features of the observed terrestrial hydrology, there are numerous differences in detail from observations. The simulated mean annual discharge is within +/-20% at only 13 of 90 fluvial gauging stations compared. In general, the discharge is overestimated for most of the northern high latitudes, midcontinental North America, eastern Europe. central and eastern Asia, India, and northern Africa. Only in western Europe and eastern North America is the discharge consistently underestimated. Although there appears to be a need for improved simulation of land surface physics in the NCEP product and parameterization of how velocities within HYDRA, the timing of the monthly mean discharge is in fair agreement with the observations. Including lakes within HYDRA reduces the amplitude of the seasonal cycle of discharge and the magnitude of the annual mean discharge of the St. Lawrence River system, in qualitative agreement with the observations. In addition, including the wetlands of the Sudd reduces the magnitude of the simulated annual discharge of the Nile River to values in better agreement with observations. Finally, the impact of man-made dams and their reservoirs on the magnitude of monthly mean discharge can be explicitly included within HYDRA. As an example, including darns and reservoirs on the Parana River improves the agreement of the simulated mean monthly discharge with observations by reducing the amplitude of the seasonal cycle to values in good agreement with the observations. The results of this study show that, although improvements can be obtained through better representations of flow velocities and more accurate digital elevation models. HYDRA can be a powerful tool for diagnosing simulated terrestrial hydrology and investigations of global climate change. | |||||
BibTeX:
@article{coe_modeling_2000, author = {Coe, M. T.}, title = {Modeling terrestrial hydrological systems at the continental scale: Testing the accuracy of an atmospheric GCM}, journal = {Journal of Climate}, year = {2000}, volume = {13}, number = {4}, pages = {686--704}, url = {://WOS:000086303700002 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282000%29013%3C0686%3AMTHSAT%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0442(2000)013%3C0686:mthsat%3E2.0.co;2} } |
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Cochrane, T. and Cochrane, T. | Diversity of the Land Resources in the Amazonian State of Rondônia, Brazil [BibTeX] |
2006 | Acta Amazonica Vol. 36(1), pp. 91 - 102 |
article | |
BibTeX:
@article{cochrane_diversity_2006, author = {Cochrane, T.T. and Cochrane, T.A.}, title = {Diversity of the Land Resources in the Amazonian State of Rondônia, Brazil}, journal = {Acta Amazonica}, year = {2006}, volume = {36}, number = {1}, pages = {91 -- 102} } |
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Cochrane, M.A. and Souza, C.M. | Linear mixture model classification of burned forests in the Eastern Amazon | 1998 | International Journal of Remote Sensing Vol. 19(17), pp. 3433-3440 |
article | URL |
Abstract: A methodology is described for detecting and classifying burned forests in Amazonia. Linear mixture models using three image endmembers (vegetation, soil, shade) were used to separate forest from non-forest. Forested areas were unmixed using vegetation, non-photosynthetic vegetation (NPV) and shade endmembers and reclassified as unburned, recently burned and older burned forests. The NPV fraction provided the greatest separability of the forest classes and has potential for subclassification of burned areas into damage classes. For 184 km(2) of burned forest, a conservative estimate of 9% (22 metric tons ha(-1)) of living biomass was lost due to forest fires between 1991-1993. | |||||
BibTeX:
@article{cochrane_linear_1998, author = {Cochrane, M. A. and Souza, C. M.}, title = {Linear mixture model classification of burned forests in the Eastern Amazon}, journal = {International Journal of Remote Sensing}, year = {1998}, volume = {19}, number = {17}, pages = {3433--3440}, url = {://WOS:000077698900017} } |
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Cochrane, M.A. and Schulze, M.D. | Fire as a recurrent event in tropical forests of the eastern Amazon: Effects on forest structure, biomass, and species composition | 1999 | Biotropica Vol. 31(1), pp. 2-16 |
article | DOI URL |
Abstract: The effects of fire on forest structure and composition were studied in a severely fire-impacted landscape in the eastern Amazon. Extensive sampling of area forests was used to compare structure and compositional differences between burned and unburned forest stands. Burned forests were extremely heterogeneous, with substantial variation in forest structure and fire damage recorded over distances of textless50 m. Unburned forest patches occurred within burned areas, but accounted for only six percent of the sample area. Canopy cover, living biomass, and living adult stem densities decreased with increasing fire intensity/frequency, and were as low as 10-30 percent of unburned forest values. Even light burns removed textgreater70 percent of the sapling and vine populations. Pioneer abundance increased dramatically with burn intensity, with pioneers dominating the understory in severely damaged areas. Species richness was inversely related to burn severity, but no clear pattern of species selection was observed. Fire appears to be a cyclical event in the study region: textless30 percent of the burned forest sample had been subjected to only one burn. Based on estimated solar radiation intensities, burning substantially increases fire susceptibility of forests. At least 50 percent of the total area of all burned forests is predicted to become flammable within Ib rainless days, as opposed to only 4 percent of the unburned forest. In heavily burned forest subjected to recurrent fires, 95 percent of the area is predicted to become flammable in textless9 rain-free days. As a recurrent disturbance phenomenon, fire shows unparalleled potential to impoverish and alter the forests of the eastern Amazon. | |||||
BibTeX:
@article{cochrane_fire_1999, author = {Cochrane, M. A. and Schulze, M. D.}, title = {Fire as a recurrent event in tropical forests of the eastern Amazon: Effects on forest structure, biomass, and species composition}, journal = {Biotropica}, year = {1999}, volume = {31}, number = {1}, pages = {2--16}, url = {://WOS:000079672600001 http://onlinelibrary.wiley.com/store/10.1111/j.1744-7429.1999.tb00112.x/asset/j.1744-7429.1999.tb00112.x.pdf?v=1&t=h6hyu14h&s=0f760d51ecb6accf3ce7930c2f12c54ec1a5b683}, doi = {https://doi.org/10.1111/j.1744-7429.1999.tb00112.x} } |
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Cochrane, M.A. and Schulze, M.D. | Forest fires in the Brazilian Amazon [BibTeX] |
1998 | Conservation Biology Vol. 12(5), pp. 948-950 |
article | DOI URL |
BibTeX:
@article{cochrane_forest_1998, author = {Cochrane, M. A. and Schulze, M. D.}, title = {Forest fires in the Brazilian Amazon}, journal = {Conservation Biology}, year = {1998}, volume = {12}, number = {5}, pages = {948--950}, url = {://WOS:000076272800006 http://onlinelibrary.wiley.com/store/10.1046/j.1523-1739.1998.012005948.x/asset/j.1523-1739.1998.012005948.x.pdf?v=1&t=h6hyti74&s=ab2da8f47cdd76c8fc561107ded23a787b392449}, doi = {https://doi.org/10.1046/j.1523-1739.1998.012005948.x} } |
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Cochrane, M. and Laurance, W. | Synergisms among Fire, Land Use, and Climate Change in the Amazon | 2008 | Ambio Vol. 37(7-8), pp. 522-527 |
article | URL |
Abstract: The Amazon is being rapidly transformed by fire. Logging and forest fragmentation sharply elevate fire incidence by increasing forest desiccation and fuel loads, and forests that have experienced a low-intensity surface fire are vulnerable to far more catastrophic fires. Satellites typically detect thermal signatures from 40 000 to 50 000 separate fires in the Amazon each year, and this number could increase as new highways and infrastructure expand across the basin. Many are concerned that large-scale deforestation, by reducing regional evapo-transpiration and creating moisture-trapping smoke plumes, will make the basin increasingly vulnerable to fire. The Amazon may also be affected by future global warming and atmospheric changes, although much remains uncertain. Most models suggest the basin will become warmer throughout this century, although there is no consensus about how precipitation will be affected. The most alarming scenarios project a permanent disruption of the El Nino-Southern Oscillation, leading to greatly increased drought or destructive synergisms between regional and global climate change in the Amazon. | |||||
BibTeX:
@article{cochrane_synergisms_2008, author = {Cochrane, M.A. and Laurance, W.F.}, title = {Synergisms among Fire, Land Use, and Climate Change in the Amazon}, journal = {Ambio}, year = {2008}, volume = {37}, number = {7-8}, pages = {522--527}, url = {://WOS:000262292000002} } |
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Cochrane, M.A. and Laurance, W.F. | Fire as a large-scale edge effect in Amazonian forests | 2002 | Journal of Tropical Ecology Vol. 18, pp. 311-325 |
article | DOI URL |
Abstract: Amazonian forests are being rapidly cleared, and the remaining forest fragments appear unusually vulnerable to fire. This occurs because forest remnants have dry, Ere-prone edges, are juxtaposed with frequently burned pastures, and are often degraded by selective logging, which increases forest desiccation and fuel loading. Here we demonstrate that in eastern Amazonia, fires are operating as a large-scale edge effect in the sense that most fires originate outside fragments and penetrate considerable distances into forest interiors. Multi-temporal analyses of satellite imagery from two frontier areas reveal that fire frequency over 12-14-y periods was substantially elevated within at least 2400 m of forest margins. Application of these data with a mathematical core-area model suggests that even large forest remnants (up to several hundred thousand ha in area) could be vulnerable to edge-related fires. The synergistic interactions of forest fragmentation, logging and human-ignited fires pose critical threats to Amazonian forests, particularly in more seasonal areas of the basin. | |||||
BibTeX:
@article{cochrane_fire_2002, author = {Cochrane, M. A. and Laurance, W. F.}, title = {Fire as a large-scale edge effect in Amazonian forests}, journal = {Journal of Tropical Ecology}, year = {2002}, volume = {18}, pages = {311--325}, url = {://WOS:000174907100001 http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=100029}, doi = {https://doi.org/10.1017/s0266467402002237} } |
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Cochrane, M.A. and Barber, C.P. | Climate change, human land use and future fires in the Amazon | 2009 | Global Change Biology Vol. 15(3), pp. 601-612 |
article | DOI URL |
Abstract: There is increasing consensus that the global climate will continue to warm over the next century. The biodiversity-rich Amazon forest is a region of growing concern because many global climate model (GCM) scenarios of climate change forecast reduced precipitation and, in some cases, coupled vegetation models predict dieback of the forest. To date, fires have generally been spatially co-located with road networks and associated human land use because almost all fires in this region are anthropogenic in origin. Climate change, if severe enough, could alter this situation, potentially changing the fire regime to one of increased fire frequency and severity for vast portions of the Amazon forest. High moisture contents and dense canopies have historically made Amazonian forests extremely resistant to fire spread. Climate will affect the fire situation in the Amazon directly, through changes in temperature and precipitation, and indirectly, through climate-forced changes in vegetation composition and structure. The frequency of drought will be a prime determinant of both how often forest fires occur and how extensive they become. Fire risk management needs to take into account landscape configuration, land cover types and forest disturbance history as well as climate and weather. Maintaining large blocks of unsettled forest is critical for managing landscape level fire in the Amazon. The Amazon has resisted previous climate changes and should adapt to future climates as well if landscapes can be managed to maintain natural fire regimes in the majority of forest remnants. | |||||
BibTeX:
@article{cochrane_climate_2009, author = {Cochrane, Mark A. and Barber, Christopher P.}, title = {Climate change, human land use and future fires in the Amazon}, journal = {Global Change Biology}, year = {2009}, volume = {15}, number = {3}, pages = {601--612}, url = {://WOS:000263134600006 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2008.01786.x/asset/j.1365-2486.2008.01786.x.pdf?v=1&t=h6hww2fi&s=03405260505271e759c7cba5163e3530523aadb1}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01786.x} } |
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Cochrane, M.A., Alencar, A., Schulze, M.D., Souza, C.M., Nepstad, D.C., Lefebvre, P. and Davidson, E.A. | Positive feedbacks in the fire dynamic of closed canopy tropical forests | 1999 | Science Vol. 284(5421), pp. 1832-1835 |
article | DOI URL |
Abstract: The incidence and importance of fire in the Amazon have increased substantially during the past decade, but the effects of this disturbance force are still poorly understood. The forest fire dynamics in two regions of the eastern Amazon were studied. Accidental fires have affected nearly 50 percent of the remaining forests and have caused more deforestation than has intentional clearing in recent years. Forest fires create positive feedbacks in future fire susceptibility, fuel loading, and fire intensity. Unless current land use and fire use practices are changed, fire has the potential to transform large areas of tropical forest into scrub or savanna. | |||||
BibTeX:
@article{cochrane_positive_1999, author = {Cochrane, M. A. and Alencar, A. and Schulze, M. D. and Souza, C. M. and Nepstad, D. C. and Lefebvre, P. and Davidson, E. A.}, title = {Positive feedbacks in the fire dynamic of closed canopy tropical forests}, journal = {Science}, year = {1999}, volume = {284}, number = {5421}, pages = {1832--1835}, url = {://WOS:000080809000049 http://www.sciencemag.org/content/284/5421/1832}, doi = {https://doi.org/10.1126/science.284.5421.1832} } |
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Cochrane, M.A. | Fire science for rainforests | 2003 | Nature Vol. 421(6926), pp. 913-919 |
article | DOI URL |
Abstract: Forest fires are growing in size and frequency across the tropics. Continually eroding fragmented forest edges, they are unintended ecological disturbances that transcend deforestation to degrade vast regions of standing forest, diminishing ecosystem services and the economic potential of these natural resources. Affecting the health of millions, net forest fire emissions may have released carbon equivalent to 41% of worldwide fossil fuel use in 1997-98. Episodically more severe during El Nino events, pan-tropical forest fires will increase as more damaged, less fire-resistant, forests cover the landscape. Here I discuss the current state of tropical fire science and make recommendations for advancement. | |||||
BibTeX:
@article{cochrane_fire_2003, author = {Cochrane, M. A.}, title = {Fire science for rainforests}, journal = {Nature}, year = {2003}, volume = {421}, number = {6926}, pages = {913--919}, note = {Edition: 2003/02/28}, url = {://WOS:000181186900040 http://www.nature.com/nature/journal/v421/n6926/pdf/nature01437.pdf}, doi = {https://doi.org/10.1038/nature01437} } |
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Cochrane, M.A. | In the line of fire - Understanding the impacts of tropical forest fires [BibTeX] |
2001 | Environment Vol. 43(8), pp. 28-38 |
article | URL |
BibTeX:
@article{cochrane_line_2001, author = {Cochrane, M. A.}, title = {In the line of fire - Understanding the impacts of tropical forest fires}, journal = {Environment}, year = {2001}, volume = {43}, number = {8}, pages = {28--38}, url = {://WOS:000171418100005} } |
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Cochrane, M.A. | Synergistic interactions between habitat fragmentation and fire in evergreen tropical forests | 2001 | Conservation Biology Vol. 15(6), pp. 1515-1521 |
article | DOI URL |
Abstract: The growing prevalence of fragmentation and fire in tropical forests makes it imperative to quant fy changes in these disturbances and to understand the ways in which they interact across the landscape. I used a multitemporal series of Landsat images to study the incidence and coincidence of fire and fragmentation in two areas of Para state in the eastern Brazilian Amazon,, Tailandia and Paragominase. In both areas, deforestation and forest fires were quantified for time series of 6-10years. The Tailandia study area typifies a landscape with The herringbone pattern of government-settled colonists, and the Paragominas area is dominated by large cattle ranches. In both areas, over 90% of the forests affected by fire were associated with form est edges. Although most burned forest occurred within 500 m of forest edges, some fires occurred in deep forest, several kilometers from any edge. The obvious synergism between forest fragmentation and fire poses serious risks to tropical ecosystems and has important implications for land management. | |||||
BibTeX:
@article{cochrane_synergistic_2001, author = {Cochrane, M. A.}, title = {Synergistic interactions between habitat fragmentation and fire in evergreen tropical forests}, journal = {Conservation Biology}, year = {2001}, volume = {15}, number = {6}, pages = {1515--1521}, url = {://WOS:000172692900010 http://onlinelibrary.wiley.com/store/10.1046/j.1523-1739.2001.01091.x/asset/j.1523-1739.2001.01091.x.pdf?v=1&t=h6hysmnq&s=400e1839a3f48dc80644204f1399e5aaa3113354}, doi = {https://doi.org/10.1046/j.1523-1739.2001.01091.x} } |
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Cochrane, M.A. | Using vegetation reflectance variability for species level classification of hyperspectral data | 2000 | International Journal of Remote Sensing Vol. 21(10), pp. 2075-2087 |
article | DOI URL |
Abstract: A study was conducted to investigate whether reflectance data from vegetation in a tropical forest canopy could be used for species level discrimination. Reflectance spectra of 11 species were analysed at the scale of the leaf, branch, tree and species. To enhance separation of species-of-interest spectra from the other spectra in the data, the variation in reflectance values for the species-of-interest were used to create a characteristic spectral shape. With a simple algorithm, the resultant shape-space was used as a data filter that correctly discriminated against 94% of the non-species-of-interest trees. | |||||
BibTeX:
@article{cochrane_using_2000, author = {Cochrane, M. A.}, title = {Using vegetation reflectance variability for species level classification of hyperspectral data}, journal = {International Journal of Remote Sensing}, year = {2000}, volume = {21}, number = {10}, pages = {2075--2087}, url = {://WOS:000087470500008}, doi = {https://doi.org/10.1080/01431160050021303} } |
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Cleveland, C.C., Houlton, B.Z., Neill, C., Reed, S.C., Townsend, A.R. and Wang, Y. | Using indirect methods to constrain symbiotic nitrogen fixation rates: a case study from an Amazonian rain forest | 2010 | Biogeochemistry Vol. 99(1-3), pp. 1-13 |
article | DOI URL |
Abstract: Human activities have profoundly altered the global nitrogen (N) cycle. Increases in anthropogenic N have had multiple effects on the atmosphere, on terrestrial, freshwater and marine ecosystems, and even on human health. Unfortunately, methodological limitations challenge our ability to directly measure natural N inputs via biological N fixation (BNF)-the largest natural source of new N to ecosystems. This confounds efforts to quantify the extent of anthropogenic perturbation to the N cycle. To address this gap, we used a pair of indirect methods-analytical modeling and N balance-to generate independent estimates of BNF in a presumed hotspot of N fixation, a tropical rain forest site in central Rondnia in the Brazilian Amazon Basin. Our objectives were to attempt to constrain symbiotic N fixation rates in this site using indirect methods, and to assess strengths and weaknesses of this approach by looking for areas of convergence and disagreement between the estimates. This approach yielded two remarkably similar estimates of N fixation. However, when compared to a previously published bottom-up estimate, our analysis indicated much lower N inputs via symbiotic BNF in the Rondnia site than has been suggested for the tropics as a whole. This discrepancy may reflect errors associated with extrapolating bottom-up fluxes from plot-scale measures, those resulting from the indirect analyses, and/or the relatively low abundance of legumes at the Rondnia site. While indirect methods have some limitations, we suggest that until the technological challenges of directly measuring N fixation are overcome, integrated approaches that employ a combination of model-generated and empirically-derived data offer a promising way of constraining N inputs via BNF in natural ecosystems. | |||||
BibTeX:
@article{cleveland_using_2010, author = {Cleveland, Cory C. and Houlton, Benjamin Z. and Neill, Christopher and Reed, Sasha C. and Townsend, Alan R. and Wang, Yingping}, title = {Using indirect methods to constrain symbiotic nitrogen fixation rates: a case study from an Amazonian rain forest}, journal = {Biogeochemistry}, year = {2010}, volume = {99}, number = {1-3}, pages = {1--13}, url = {://WOS:000279025100001 http://www.springerlink.com/content/et763xu480xt16q1/fulltext.pdf}, doi = {https://doi.org/10.1007/s10533-009-9392-y} } |
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Claeys, M., Kourtchev, I., Pashynska, V., Vas, G., Vermeylen, R., Wang, W., Cafmeyer, J., Chi, X., Artaxo, P., Andreae, M.O. and Maenhaut, W. | Polar organic marker compounds in atmospheric aerosols during the LBA-SMOCC 2002 biomass burning experiment in Rondonia, Brazil: sources and source processes, time series, diel variations and size distributions | 2010 | Atmospheric Chemistry and Physics Vol. 10(19), pp. 9319-9331 |
article | DOI URL |
Abstract: Measurements of polar organic marker compounds were performed on aerosols that were collected at a pasture site in the Amazon basin (Rondonia, Brazil) using a high-volume dichotomous sampler (HVDS) and a Micro-Orifice Uniform Deposit Impactor (MOUDI) within the framework of the 2002 LBA-SMOCC (Large-Scale Biosphere Atmosphere Experiment in Amazonia - Smoke Aerosols, Clouds, Rainfall, and Climate: Aerosols From Biomass Burning Perturb Global and Regional Climate) campaign. The campaign spanned the late dry season (biomass burning), a transition period, and the onset of the wet season (clean conditions). In the present study a more detailed discussion is presented compared to previous reports on the behavior of selected polar marker compounds, including levoglucosan, malic acid, isoprene secondary organic aerosol (SOA) tracers and tracers for fungal spores. The tracer data are discussed taking into account new insights that recently became available into their stability and/or aerosol formation processes. During all three periods, levoglucosan was the most dominant identified organic species in the PM(2.5) size fraction of the HVDS samples. In the dry period levoglucosan reached concentrations of up to 7.5 mu g m(-3) and exhibited diel variations with a nighttime prevalence. It was closely associated with the PM mass in the size-segregated samples and was mainly present in the fine mode, except during the wet period where it peaked in the coarse mode. Isoprene SOA tracers showed an average concentration of 250 ng m(-3) during the dry period versus 157 ng m(-3) during the transition period and 52 ng m(-3) during the wet period. Malic acid and the 2-methyltetrols exhibited a different size distribution pattern, which is consistent with different aerosol formation processes (i.e., gas-to-particle partitioning in the case of malic acid and heterogeneous formation from gas-phase precursors in the case of the 2-methyltetrols). The 2-methyltetrols were mainly associated with the fine mode during all periods, while malic acid was prevalent in the fine mode only during the dry and transition periods, and dominant in the coarse mode during the wet period. The sum of the fungal spore tracers arabitol, mannitol, and erythritol in the PM(2.5) fraction of the HVDS samples during the dry, transition, and wet periods was, on average, 54 ng m(-3), 34 ng m(-3), and 27 ng m(-3), respectively, and revealed minor day/night variation. The mass size distributions of arabitol and mannitol during all periods showed similar patterns and an association with the coarse mode, consistent with their primary origin. The results show that even under the heavy smoke conditions of the dry period a natural background with contributions from bioaerosols and isoprene SOA can be revealed. The enhancement in isoprene SOA in the dry season is mainly attributed to an increased acidity of the aerosols, increased NO(x) concentrations and a decreased wet deposition. | |||||
BibTeX:
@article{claeys_polar_2010, author = {Claeys, M. and Kourtchev, I. and Pashynska, V. and Vas, G. and Vermeylen, R. and Wang, W. and Cafmeyer, J. and Chi, X. and Artaxo, P. and Andreae, M. O. and Maenhaut, W.}, title = {Polar organic marker compounds in atmospheric aerosols during the LBA-SMOCC 2002 biomass burning experiment in Rondonia, Brazil: sources and source processes, time series, diel variations and size distributions}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {19}, pages = {9319--9331}, url = {://WOS:000283066300006 http://www.atmos-chem-phys.net/10/9319/2010/acp-10-9319-2010.pdf}, doi = {https://doi.org/10.5194/acp-10-9319-2010} } |
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Claeys, M., Graham, B., Vas, G., Wang, W., Vermeylen, R., Pashynska, V., Cafmeyer, J., Guyon, P., Andreae, M.O., Artaxo, P. and Maenhaut, W. | Formation of secondary organic aerosols through photooxidation of isoprene | 2004 | Science Vol. 303(5661), pp. 1173-1176 |
article | DOI URL |
Abstract: Detailed organic analysis of natural aerosols from the Amazonian rain forest showed considerable quantities of previously unobserved polar organic compounds, which were identified as a mixture of two diastereoisomeric 2-methyltetrols: 2-methylthreitol and 2-methylerythritol. These polyols, which have the isoprene skeleton, can be explained by OH radical-initiated photooxidation of isoprene. They have low vapor pressure, allowing them to condense onto preexisting particles. It is estimated that photooxidation of isoprene results in an annual global production of about 2 teragrams of the polyols, a substantial fraction of the Intergovernmental Panel on Climate Change estimate of between 8 and 40 teragrams per year of secondary organic aerosol from biogenic sources. | |||||
BibTeX:
@article{claeys_formation_2004, author = {Claeys, M. and Graham, B. and Vas, G. and Wang, W. and Vermeylen, R. and Pashynska, V. and Cafmeyer, J. and Guyon, P. and Andreae, M. O. and Artaxo, P. and Maenhaut, W.}, title = {Formation of secondary organic aerosols through photooxidation of isoprene}, journal = {Science}, year = {2004}, volume = {303}, number = {5661}, pages = {1173--1176}, url = {://WOS:000189074700040 http://www.sciencemag.org/content/303/5661/1173}, doi = {https://doi.org/10.1126/science.1092805} } |
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Cirino, G., Souza, R., Adams, D. and Artaxo, P. | The effect of atmospheric aerosol particles and clouds on net ecosystem exchange in the Amazon [BibTeX] |
2014 | Atmos. Chem. Phys. Vol. 14, pp. 6523-6543 |
article | |
BibTeX:
@article{cirino_effect_2014, author = {Cirino, G.G. and Souza, R.A.F. and Adams, D.K. and Artaxo, P.}, title = {The effect of atmospheric aerosol particles and clouds on net ecosystem exchange in the Amazon}, journal = {Atmos. Chem. Phys.}, year = {2014}, volume = {14}, pages = {6523--6543} } |
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Cirino, G., Brito, J., Barbosa, H., Rizzo, L., Tunve, P., Sá, S., Jimenez, J., Palm, B., Carbone, S., Lavric, J., Souza, R., Wolff, S., Walter, D., Tota, J., Oliveira, M., Martin, S. and Artaxo, P. | Observations of Manaus urban plume evolution and interaction with biogenic emissions in GoAmazon 2014/5 [BibTeX] |
2018 | Atmospheric Environment Vol. 191, pp. 513-524 |
article | DOI |
BibTeX:
@article{cirino_observations_2018, author = {Cirino, G. and Brito, J. and Barbosa, H.M.J. and Rizzo, L.V. and Tunve, P. and Sá, S.S. and Jimenez, J.L. and Palm, B.B. and Carbone, S. and Lavric, J.V. and Souza, R.A.F. and Wolff, S. and Walter, D. and Tota, J. and Oliveira, M.B.L. and Martin, S.T. and Artaxo, P.}, title = {Observations of Manaus urban plume evolution and interaction with biogenic emissions in GoAmazon 2014/5}, journal = {Atmospheric Environment}, year = {2018}, volume = {191}, pages = {513--524}, doi = {https://doi.org/10.1016/j.atmosenv.2018.08.031} } |
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Cintra, J., Emilio, T., Martins, D., Moulatlet, G., Souza, P., Levis, C., Quesada, C.A., Schöngart J., B. and Schietti | Productivity of aboveground coarse wood biomass and stand age related to soil hydrology of Amazonian forests in the Purus-Madeira interfluvial area [BibTeX] |
2013 | Biogeosciences Vol. 10, pp. 7759-7774 |
article | |
BibTeX:
@article{cintra_productivity_2013, author = {Cintra, J.; Emilio, T.; Martins, D.; Moulatlet, G.; Souza, P.; Levis, C.; Quesada, C. A.; Schöngart, J., B.B.L.; Schietti}, title = {Productivity of aboveground coarse wood biomass and stand age related to soil hydrology of Amazonian forests in the Purus-Madeira interfluvial area}, journal = {Biogeosciences}, year = {2013}, volume = {10}, pages = {7759--7774} } |
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Cifelli, R., Petersen, W.A., Carey, L.D., Rutledge, S.A. and Dias, M. | Radar observations of the kinematic, microphysical, and precipitation characteristics of two MCSs in TRMM LBA | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Dual-Doppler and polarimetric radar observations are used to analyze two mesoscale convective systems (MCSs) that occurred during the Tropical Rainfall Measuring Mission Large-Scale Biosphere-Atmosphere field campaign. The MCSs formed in different meteorological regimes, based on profiles of atmospheric wind and thermodynamic data. The first MCS event (26 January 1999) was a squall line that formed in low-level easterly flow and had an intense leading line of convection. In contrast, the 25 February 1999 MCS formed in low-level westerly flow and was best characterized by stratiform precipitation with embedded convective elements. The radar analyses suggest that the MCSs were distinct in terms of overall vertical structure characteristics. In particular, polarimetric radar cross sections indicated the presence of an active mixed phase zone in the easterly MCS that was largely absent in the westerly case. The easterly MCS had considerably more precipitation ice in the middle to upper troposphere compared to the westerly MCS. Composite analyses showed that the easterly MCS had higher peak reflectivities and a smaller reflectivity gradient above the 0degreesC level in convective regions of the storm compared to the westerly MCS event. Moreover, mean profiles of both vertical air motion and vertical mass transport in the convective portion of the easterly MCS were larger (over a factor of 2 at some heights below the 0degreesC level) than those in the westerly event. These observations suggest that the easterly and westerly wind regimes in the southwest Amazon region produce convection with different vertical structure characteristics, similar to regimes elsewhere in the global tropics (e. g., maritime continent). | |||||
BibTeX:
@article{cifelli_radar_2002, author = {Cifelli, R. and Petersen, W. A. and Carey, L. D. and Rutledge, S. A. and Dias, Mafd}, title = {Radar observations of the kinematic, microphysical, and precipitation characteristics of two MCSs in TRMM LBA}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200044 http://www.agu.org/journals/jd/jd0218/2000JD000264/2000JD000264.pdf}, doi = {https://doi.org/10.1029/2000jd000264} } |
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Cifelli, R., Carey, L., Petersen, W.A. and Rutledge, S.A. | An ensemble study of wet season convection in southwest Amazonia: Kinematics and implications for diabatic heating | 2004 | Journal of Climate Vol. 17(24), pp. 4692-4707 |
article | DOI URL |
Abstract: Dual-Doppler radar data from the Tropical Rainfall Measuring Mission Large Scale Biosphere-Atmosphere Experiment in Amazonia (TRMM-LBA) field campaign are used to determine characteristic kinematic and reflectivity vertical structures associated with precipitation features observed during the wet season in the southwest region of Amazonia. Case studies of precipitating systems during TRMM-LBA as well as overarching satellite studies have shown large differences in convective intensity associated with changes that develop in low-level easterly flow [east regime (ER)] and westerly flow [ west regime (WR)]. This study attempts to examine the vertical kinematic and heating structure of convection across the spectrum of precipitation features that occurred in each regime. Results show that convection in the ER is characterized by more intense updrafts and larger radar reflectivities above the melting level, in agreement with results from lightning detection networks. These regime differences are consistent with contrasts in composite thermal buoyancy between the regimes: above the boundary layer, the environment in the ER is characterized by a greater virtual temperature excess for near-surface rising parcels. Both regimes showed a peak in intensity during the late afternoon hours, as evidenced by radar reflectivity and kinematic characteristics, consistent with previous studies of rainfall and lightning in the Rondonia (TRMM-LBA) region. After sunset, however, convective intensity in the WR decreases much more abruptly compared to the ER. In the stratiform-weak convective region, the ER showed both reflectivity and kinematic characteristics of classic stratiform structure after sunset through the early morning hours, consistent with the life cycle of mesoscale conjective systems (MCSs). Apparent heating (Q(1)) profiles were constructed for each regime assuming the vertical advection of dry static energy was the dominant forcing term. The resulting profiles show a peak centered near 8 km in the convective regions of both regimes, although the ER has a broader maximum compared to the WR. The breadth of the ER diabatic heating peak is consistent with the more dominant role of ice processes in ER convection. | |||||
BibTeX:
@article{cifelli_ensemble_2004, author = {Cifelli, R. and Carey, L. and Petersen, W. A. and Rutledge, S. A.}, title = {An ensemble study of wet season convection in southwest Amazonia: Kinematics and implications for diabatic heating}, journal = {Journal of Climate}, year = {2004}, volume = {17}, number = {24}, pages = {4692--4707}, url = {://WOS:000226084900007 http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-3236.1}, doi = {https://doi.org/10.1175/jcli-3236.1} } |
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Christoffersen, B., Restrepo-Coupe, N., Arain, M., Baker, I., Cestaro, B., Ciais, P., Fisher, J., Galbraith, D., Guan, X., Gulden, L., van den Hurk, l., Ichii, K., Imbuzeiro, H., Jain, A., Levine, N., Miguez-Machor, G., Poulters, B., Robertit, D., Sakaguchi, K., Sahoou, A., Schaeferv, K., Shik, M., Verbeeck, H., Yang, Z.-L., Araújo, A.C., Kruijt, B., Manzi, A., Rocha, H.R.d., von Randow, C., Muza, M. and Borak, J. | Mechanisms of water supply and vegetation demand govern the seasonality and magnitude of evapotranspiration in Amazonia and Cerrado [BibTeX] |
2014 | Agricultural and Forest Meteorology Vol. 191(15), pp. 33-50 |
article | |
BibTeX:
@article{christoffersen_mechanisms_2014, author = {Christoffersen, B.O. and Restrepo-Coupe, N. and Arain, M.A. and Baker, I.T. and Cestaro, B.P. and Ciais, P. and Fisher, J.B. and Galbraith, D. and Guan, X. and Gulden, L. and van den Hurk, l.B. and Ichii, K. and Imbuzeiro, H.M.A. and Jain, A. and Levine, N. and Miguez-Machor, G. and Poulters, B. and Robertit, D.R. and Sakaguchi, K. and Sahoou, A. and Schaeferv, K. and Shik, M. and Verbeeck, Hans and Yang, Zong-Liang and Araújo, Alessandro C. and Kruijt, B. and Manzi, A.O. and Rocha, H. R. da and von Randow, C. and Muza, M.N. and Borak, J.}, title = {Mechanisms of water supply and vegetation demand govern the seasonality and magnitude of evapotranspiration in Amazonia and Cerrado}, journal = {Agricultural and Forest Meteorology}, year = {2014}, volume = {191}, number = {15}, pages = {33--50} } |
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Christianson, D., Varadharajan, C., Christoffersen, B., Detto, M., Faybishenko, B., Gimenez, B., Hendrix, V., Jardine, K.J., Negron-Juarez, R., Pastorello, G., Powell, T., Sandesh, M., Warren, J., Wolfe, B., Chambers, J., Kueppers, L., McDowell, N. and Agarwal, D. | A metadata reporting framework (FRAMES) for synthesis of ecohydrological observations [BibTeX] |
2017 | Ecological Informatics Vol. 42, pp. 148-158 |
article | |
BibTeX:
@article{christianson_metadata_2017, author = {Christianson, D.S. and Varadharajan, C. and Christoffersen, B. and Detto, M. and Faybishenko, B. and Gimenez, B.O. and Hendrix, V. and Jardine, K. J. and Negron-Juarez, R. and Pastorello, G.Z. and Powell, T.L. and Sandesh, M. and Warren, J.M. and Wolfe, B.T. and Chambers, J.Q. and Kueppers, L.M. and McDowell, N.G. and Agarwal, D.A.}, title = {A metadata reporting framework (FRAMES) for synthesis of ecohydrological observations}, journal = {Ecological Informatics}, year = {2017}, volume = {42}, pages = {148--158} } |
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Chou, W.W., Wofsy, S.C., Harriss, R.C., Lin, J.C., Gerbig, C. and Sachse, G.W. | Net fluxes of CO2 in Amazonia derived from aircraft observations | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D22) |
article | DOI URL |
Abstract: A conceptual framework is developed using atmospheric measurements from aircraft to determine fluxes of CO2 from a continental land area. The concepts are applied to measurements of CO2, O-3, and CO concentrations from the Amazon Boundary Layer Experiment (ABLE-2B, April-May 1987) to estimate fluxes of CO2 for central and eastern Amazonia late in the wet season of 1987. We observed that column amounts of CO2 from 0 to 3 km decreased during the day over Amazonia at the average rate of -6.3+/-1 mumol m(-2) s(-1), corresponding to an uptake flux modestly smaller than the daytime uptake (-10.2 mumol m(-2) s(-1)) at a flux tower in the study area. The estimated net flux of CO2, integrated over 24 hours, was -0.03+/-0.2 mumol m(-2) s(-1), indicating that the carbon budget of a substantial area of central Amazonia was close to balance in April 1987. We argue that net CO2 fluxes on the continental scale of Amazonia, with its heterogeneous landscape and large areas of inundation, are strongly modified by the influence of seasonal hydrological factors that enhance respiration and decomposition in forests and wetlands, offsetting growth of forest trees in the wet season. | |||||
BibTeX:
@article{chou_net_2002, author = {Chou, W. W. and Wofsy, S. C. and Harriss, R. C. and Lin, J. C. and Gerbig, C. and Sachse, G. W.}, title = {Net fluxes of CO2 in Amazonia derived from aircraft observations}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D22}, url = {://WOS:000180867500012 http://www.agu.org/journals/jd/jd0222/2001JD001295/2001JD001295.pdf}, doi = {https://doi.org/10.1029/2001jd001295} } |
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Chou, S.C., Tanajura, C.A.S., Xue, Y.K. and Nobre, C.A. | Validation of the coupled Eta/SSiB model over South America | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Two 1-month integrations were performed with the regional Eta model coupled with the Simplified Simple Biosphere model (SSiB) over South America. The goal of the present work is to validate the model and to investigate its biases and skill on the simulations of South American climate. This is an initial step on the use of this model for climate research. The Eta model was set up with 80-km horizontal resolution and 38 vertical layers over the South American continent and part of the adjacent oceans. Analyses from the National Centers for Environmental Prediction (NCEP) were used as initial and lateral boundary conditions. The selected months were August and November 1997, which are in opposite phases of the precipitation annual cycle observed in the central part of South America. The model was integrated continuously for each 1-month period. Monthly means and daily variations of simulated precipitation and surface temperature compare well with observations. The patterns of simulated outgoing longwave radiation are also similar to the observed ones. However, a positive bias is verified in the simulations. The model shows a positive bias in latent and sensible heat surface fluxes due to an excessive shortwave incoming radiation at the surface. Comparisons with a version of the Eta model coupled with the bucket model shows that the Eta/SSiB version improves the surface temperature and increases precipitation in the interior of the continent during wet months. | |||||
BibTeX:
@article{chou_validation_2002, author = {Chou, S. C. and Tanajura, C. A. S. and Xue, Y. K. and Nobre, C. A.}, title = {Validation of the coupled Eta/SSiB model over South America}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200103 http://www.agu.org/journals/jd/jd0220/2000JD000270/2000JD000270.pdf}, doi = {https://doi.org/10.1029/2000jd000270} } |
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Chou, S.C., Marengo, J.A., Dereczynski, C.P., Waldheim, P.V. and Manzi, A.O. | Comparison of CPTEC GCM and Eta Model results with observational data from the Rondonia LBA Reference Site, Brazil | 2007 | Journal of the Meteorological Society of Japan Vol. 85A, pp. 25-42 |
article | DOI URL |
Abstract: We compared forecasts of the Center for Weather Prediction and Climate Studies (Centro de Previsao de Tempo e Estudos Climaticos-CPTEC) General Circulation Model (GCM) and the mesoscale Eta Model with observations undertaken at the Rondonia Coordinated Enhanced Observing Period (CEOP) reference site, Brazil, for the dry period between 1 July and 1 September 2001. The Rondonia site is located in the Jaru Biological Reserve Area in the state of Rondonia within the Amazon region. The site is forested and is one of the Reference Sites of the Large-Scale Biosphere-Atmosphere Experiment in the Amazon Basin (LBA) Continental-Scale Experiment (CSE). Time series and mean diurnal cycles of precipitation, near-surface temperature, latent and sensible heat fluxes, surface incoming shortwave and net radiation fluxes are shown for 24-h and 48-h forecasts. In the global model, the predicted incoming shortwave radiation and net radiation are similar to observed values; however, this is accompanied by large overestimate of deep clouds and precipitation. Partition of the available energy results in an overestimate of the sensible heat fluxes and an underestimate of the latent heat fluxes. The latent heat fluxes are large shortly after rain, but decay quickly. No clear improvement is noted in the 48-h forecasts compared with the 24-h forecasts. The Eta Model is a grid-point limited-area model. Its precipitation forecasts are similar to observations; however, the model overestimates the incoming shortwave radiation, resulting in excessive net radiation. The Eta sensible and latent heat fluxes are both overestimated, and 48-h forecasts produce small improvements over the 24-h forecasts. Near-surface temperatures are overestimated by both models. The global model requires a reduction in precipitation production, and both models require a reduction in incoming short-wave radiation at the surface. | |||||
BibTeX:
@article{chou_comparison_2007, author = {Chou, Sin Chan and Marengo, Jose A. and Dereczynski, Claudine P. and Waldheim, Patricia V. and Manzi, Antonio O.}, title = {Comparison of CPTEC GCM and Eta Model results with observational data from the Rondonia LBA Reference Site, Brazil}, journal = {Journal of the Meteorological Society of Japan}, year = {2007}, volume = {85A}, pages = {25--42}, url = {://WOS:000246144200003}, doi = {https://doi.org/10.2151/jmsj.85A.25} } |
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Chor, T.L., Dias, N.L., Araújo, A., Wolff, S., Zahn, E., Manzi, A., Trebs, I., Sá, M.O., Teixeira, P.R. and Sörgel, M. | Flux-variance and flux-gradient relationships in the roughness sublayer over the Amazon forest [BibTeX] |
2017 | Agricultural and Forest Meteorology Vol. 239, pp. 213-222 |
article | DOI |
BibTeX:
@article{chor_flux-variance_2017, author = {Chor, Tomás L. and Dias, Nelson L. and Araújo, Alessandro and Wolff, Stefan and Zahn, Einara and Manzi, Antônio and Trebs, Ivonne and Sá, Marta O. and Teixeira, Paulo R. and Sörgel, Matthias}, title = {Flux-variance and flux-gradient relationships in the roughness sublayer over the Amazon forest}, journal = {Agricultural and Forest Meteorology}, year = {2017}, volume = {239}, pages = {213--222}, doi = {https://doi.org/10.1016/j.agrformet.2017.03.009} } |
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China, S., Burrows, S.M., Wang, B., Harder, T.H., Weis, J., Tanarhte, M., Rizzo, L.V., Brito, J., Cirino, G.G., Ma, P.-L., Cliff, J., Artaxo, P., Gilles, M.K. and Laskin, A. | Fungal spores as a source of sodium salt particles in the Amazon basin [BibTeX] |
2018 | Nature Comunications | article | DOI |
BibTeX:
@article{china_fungal_2018, author = {China, Swarup and Burrows, Susannah M. and Wang, Bingbing and Harder, Tristan H. and Weis, Johannes and Tanarhte, Meryem and Rizzo, Luciana V. and Brito, Joel and Cirino, Glauber G. and Ma, Po-Lun and Cliff, John and Artaxo, Paulo and Gilles, Mary K. and Laskin, Alexander}, title = {Fungal spores as a source of sodium salt particles in the Amazon basin}, journal = {Nature Comunications}, year = {2018}, doi = {https://doi.org/10.1038/s41467-018-07066-4} } |
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Chig Couto, E.G., Novaes Filho, J., Rodrigues, L., Johnson, M. and Weber O.L.S., L. | Distribuição espacial da granulometria, cor e carbono orgânico do solo ao longo de um transecto em microbacias na Amazônia meridional [BibTeX] |
2008 | Acta Amazonica Vol. 38, pp. 715-722 |
article | |
BibTeX:
@article{chig_distribuicao_2008, author = {Chig, Couto, E. G. ; Novaes Filho, J.P.; Rodrigues, L.C.M. ; Johnson, M. ; Weber, O.L.S., L.A.}, title = {Distribuição espacial da granulometria, cor e carbono orgânico do solo ao longo de um transecto em microbacias na Amazônia meridional}, journal = {Acta Amazonica}, year = {2008}, volume = {38}, pages = {715--722} } |
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Chian, A.C.L., Miranda, R.A., Koga, D., Bolzan, M.J.A., Ramos, F.M. and Rempel, E.L. | Analysis of phase coherence in fully developed atmospheric turbulence: Amazon forest canopy | 2008 | Nonlinear Processes in Geophysics Vol. 15(4), pp. 567-573 |
article | URL |
Abstract: In a recent paper (Koga et al., 2007) it was shown that the intermittent nature of solar wind turbulence can be characterized by kurtosis and phase coherence index. In this paper, we apply these two nonlinear time series techniques to characterize the intermittent nature of atmospheric turbulence above and within the Amazon forest canopy using the day-time data of temperature and vertical wind velocity measured by a micrometeorological tower at two different heights. By applying kurtosis and phase coherence index to quantify the degree of phase coherence, we identify an enhanced scalar-velocity similarity for in-canopy turbulence compared to the above-canopy turbulence, during the interval of data analysis. | |||||
BibTeX:
@article{chian_analysis_2008, author = {Chian, A. C. L. and Miranda, R. A. and Koga, D. and Bolzan, M. J. A. and Ramos, F. M. and Rempel, E. L.}, title = {Analysis of phase coherence in fully developed atmospheric turbulence: Amazon forest canopy}, journal = {Nonlinear Processes in Geophysics}, year = {2008}, volume = {15}, number = {4}, pages = {567--573}, url = {://WOS:000259989200007} } |
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Chen, Y, Morton, DC and Randerson, JT | North Atlantic sea surface temperatures synchronize forest carbon losses from hurricanes and Amazon fires [BibTeX] |
2015 | Geophysical Research Letters Vol. 42(15), pp. 6462-6470 |
article | DOI |
BibTeX:
@article{chen_y_north_2015, author = {Chen Y, Morton DC, Randerson JT}, title = {North Atlantic sea surface temperatures synchronize forest carbon losses from hurricanes and Amazon fires}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, number = {15}, pages = {6462--6470}, doi = {https://doi.org/10.1002/2015GL064505} } |
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Chen, Q., Lu, D., Keller, M., Santos, M.d., Bolfe, E., Feng, Y. and Wang, C. | Modeling and mapping agroforestry aboveground biomass in the Brazilian Amazon using airborne lidar data. [BibTeX] |
2016 | Remote Sensing Vol. 8(21) |
article | DOI |
BibTeX:
@article{chen_modeling_2016, author = {Chen, Q. and Lu, D. and Keller, M. and Santos, M.N. dos and Bolfe, E.L. and Feng, Y. and Wang, C.}, title = {Modeling and mapping agroforestry aboveground biomass in the Brazilian Amazon using airborne lidar data.}, journal = {Remote Sensing}, year = {2016}, volume = {8}, number = {21}, doi = {https://doi.org/10.3390/rs8010021} } |
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Chen, Q., Heald, C.L., Jimenez, J.L. and al. , e. | Elemental composition of organic aerosol:The gap between ambient and laboratory measurements [BibTeX] |
2015 | Geophysical Research Letters Vol. 42(10), pp. 4182-4189 |
article | DOI |
BibTeX:
@article{chen_elemental_2015, author = {Chen, Q. and Heald, C. L. and Jimenez, J. L. and al., et}, title = {Elemental composition of organic aerosol:The gap between ambient and laboratory measurements}, journal = {Geophysical Research Letters}, year = {2015}, volume = {42}, number = {10}, pages = {4182--4189}, doi = {https://doi.org/10.1002/2015gl063693} } |
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Chen, Q., Farmer, D.K., Schneider, J., Zorn, S.R., Heald, C.L., Karl, T.G., Guenther, A., Allan, J.D., Robinson, N., Coe, H., Kimmel, J.R., Pauliquevis, T., Borrmann, S., Poeschl, U., Andreae, M.O., Artaxo, P., Jimenez, J.L. and Martin, S.T. | Mass spectral characterization of submicron biogenic organic particles in the Amazon Basin | 2009 | Geophysical Research Letters Vol. 36 |
article | DOI URL |
Abstract: Submicron atmospheric particles in the Amazon Basin were characterized by a high-resolution aerosol mass spectrometer during the wet season of 2008. Patterns in the mass spectra closely resembled those of secondary-organic-aerosol (SOA) particles formed in environmental chambers from biogenic precursor gases. In contrast, mass spectral indicators of primary biological aerosol particles (PBAPs) were insignificant, suggesting that PBAPs contributed negligibly to the submicron fraction of particles during the period of study. For 40% of the measurement periods, the mass spectra indicate that in-Basin biogenic SOA production was the dominant source of the submicron mass fraction, contrasted to other periods (30%) during which out-of-Basin organic-carbon sources were significant on top of the baseline in-Basin processes. The in-Basin periods had an average organic-particle loading of 0.6 mu g m(-3) and an average elemental oxygen-to-carbon (O:C) ratio of 0.42, compared to 0.9 mu g m(-3) and 0.49, respectively, during periods of out-of-Basin influence. On the basis of the data, we conclude that most of the organic material composing submicron particles over the Basin derived from biogenic SOA production, a finding that is consistent with microscopy observations made in a concurrent study. This source was augmented during some periods by aged organic material delivered by long-range transport. Citation: Chen, Q., et al. (2009), Mass spectral characterization of submicron biogenic organic particles in the Amazon Basin, Geophys. Res. Lett., 36, L20806, doi: 10.1029/2009GL039880. | |||||
BibTeX:
@article{chen_mass_2009, author = {Chen, Q. and Farmer, D. K. and Schneider, J. and Zorn, S. R. and Heald, C. L. and Karl, T. G. and Guenther, A. and Allan, J. D. and Robinson, N. and Coe, H. and Kimmel, J. R. and Pauliquevis, T. and Borrmann, S. and Poeschl, U. and Andreae, M. O. and Artaxo, P. and Jimenez, J. L. and Martin, S. T.}, title = {Mass spectral characterization of submicron biogenic organic particles in the Amazon Basin}, journal = {Geophysical Research Letters}, year = {2009}, volume = {36}, url = {://WOS:000271314000003 http://www.agu.org/pubs/crossref/2009/2009GL039880.shtml}, doi = {https://doi.org/10.1029/2009gl039880} } |
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Chen, Q., Farmer, D.K., Rizzo, L.V., Pauliquevis, T., Kuwata, M., Karl, T.G., Guenther, A., Allan, J.D., Coe, H., Andreae, M.O., Pöschl, U., Jimenez, J.L., Artaxo, P. and Martin, S.T. | Submicron particle mass concentrations and sources in the Amazonian wet season (AMAZE-08). [BibTeX] |
2015 | Atmospheric Chemistry and Physics (Online) Vol. 15, pp. 3687-3701 |
article | |
BibTeX:
@article{chen_submicron_2015, author = {Chen, Q. and Farmer, D. K. and Rizzo, L. V. and Pauliquevis, T. and Kuwata, M. and Karl, T. G. and Guenther, A. and Allan, J. D. and Coe, H. and Andreae, M. O. and Pöschl, U. and Jimenez, J. L. and Artaxo, P. and Martin, S. T.}, title = {Submicron particle mass concentrations and sources in the Amazonian wet season (AMAZE-08).}, journal = {Atmospheric Chemistry and Physics (Online)}, year = {2015}, volume = {15}, pages = {3687--3701} } |
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Chen, Q., Farmer, D.K., Rizzo, L.V., Pauliqueivis, T., Kuwata, M., Karl, T.G., Guenther, A., Schneider, J., Allan, J.D., Coe, H., Andreae, M.O., Poeschl, U., Jimenez, J.L., Artaxo, P. and Martin. S., T. | Fine-Mode Organic Mass Concentrations and Sources in the Amazonian Wet Season (AMAZE-08) [BibTeX] |
2014 | Atmospheric Chemistry and Physics Discussions Vol. 14, pp. 16151-16186 |
article | DOI |
BibTeX:
@article{chen_fine-mode_2014, author = {Chen, Qi and Farmer, D. K. and Rizzo, L. V. and Pauliqueivis, T. and Kuwata, M. and Karl, T. G. and Guenther, A. and Schneider, J. and Allan, J. D. and Coe, H. and Andreae, M. O. and Poeschl, U. and Jimenez, J. L. and Artaxo, P. and T., Martin. S.}, title = {Fine-Mode Organic Mass Concentrations and Sources in the Amazonian Wet Season (AMAZE-08)}, journal = {Atmospheric Chemistry and Physics Discussions}, year = {2014}, volume = {14}, pages = {16151--16186}, note = {Section: www.atmos-chem-phys-discuss.net/14/16151/2014/}, doi = {https://doi.org/10.5194/acpd-14-16151-2014} } |
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Chazdon, E.N., Rozendaal, D.M.A., Bongers, F., Zambrano, A.M.A., Aide, T.M., Balvanera, P., Becknell, R.L., Broadbent, J., Boukili, P.H.S., Craven, D., Almeida-Cortez, J.S., Cabral, G.A.L., Jong, B., Denslow, J., Dent, D., DeWalt, V., Brancalion, S., J., Dupuy, S.M., Espírito-Santo, M.M., Fandino, M.C., César, R.G., Hall, J.S., Hernández-Stefanoni, J.L., , J.M., Durán, Jakovac, A.B., Kennard, D., Letcher, S.G., Lohbeck, M., Martínez-Ramos, M., Massoca, P., Meave, J.A., , C.C., Junqueira, Mesquita, F., Muñoz, R., Muscarella, R., Ochoa-Gaona, S., Orihuela-Belmonte, E., Peña-Claros, M., Pérez-García E., R., Mora, A., Piotto, J.S., Rodríguez-Velazquez, J., Romero-Pérez, I.E., Ruíz, J., Juan G. Saldarriaga, J.G., Sanchez, D., Powers, Azofeifa, N.B., Steininger, M.K., Swenson, N.G., Uriarte, M., van Breugel, M., van der Wal, H., Veloso M. D., A., Schwartz, M., Vester, I.C.G., Bentos, T.V., Williamson B. G. & Poorter, L.H. and Vieira | Carbon mitigation potential of Neotropical second-growth forest [BibTeX] |
2016 | Science Advances Vol. 2(5), pp. e1501639 |
article | DOI |
BibTeX:
@article{chazdon_carbon_2016, author = {Chazdon, E. N.; Rozendaal, D. M. A.; Bongers, F.; Zambrano, A. M. A.; Aide, T. M.; Balvanera, P.; Becknell, , R. L.; Broadbent and J.; Boukili, P. H. S.; Craven, D.; Almeida-Cortez, J. S.; Cabral, G. A. L.; Jong, B.; Denslow, J.; Dent, D.; DeWalt, , V.;Brancalion and S. J.; Dupuy, S. M.; Espírito-Santo, M. M.; Fandino, M. C.; César, R. G.; Hall, J. S.; Hernández-Stefanoni, J. L.;, J. M.; Durán and Jakovac, A. B.; Kennard, D.; Letcher, S. G.; Lohbeck, M.; Martínez-Ramos, M.; Massoca, P.; Meave, J. A.;, C. C.; Junqueira and Mesquita, F.; Muñoz, R.; Muscarella, R.; Ochoa-Gaona, S.; Orihuela-Belmonte, E.; Peña-Claros, M.; Pérez-García, E., R.; Mora and A.; Piotto, J. S.; Rodríguez-Velazquez, J.; Romero-Pérez, I. E.; Ruíz, J.; Juan G. Saldarriaga, J. G.; Sanchez-, D.; Powers and Azofeifa, N. B.; Steininger, M. K.; Swenson, N. G.; Uriarte, M.; van Breugel, M.; van der Wal, H.; Veloso, M. D., A.; Schwartz and M.; Vester, I. C. G.; Bentos, T. V.; Williamson, B. G. & Poorter, L., H.; Vieira}, title = {Carbon mitigation potential of Neotropical second-growth forest}, journal = {Science Advances}, year = {2016}, volume = {2}, number = {5}, pages = {e1501639}, doi = {https://doi.org/10.1126/sciadv.1501639} } |
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Chaves, J., Neill, C., Germer, S., Neto, S.G., Krusche, A.V., Bonilla, A.C. and Elsenbeer, H. | Nitrogen Transformations in Flowpaths Leading from Soils to Streams in Amazon Forest and Pasture | 2009 | Ecosystems Vol. 12(6), pp. 961-972 |
article | DOI URL |
Abstract: The modification of large areas of tropical forest to agricultural uses has consequences for the movement of inorganic nitrogen (N) from land to water. Various biogeochemical pathways in soils and riparian zones can influence the movement and retention of N within watersheds and affect the quantity exported in streams. We used the concentrations of NO(3)(-) and NH(4)(+) in different hydrological flowpaths leading from upland soils to streams to investigate inorganic N transformations in adjacent watersheds containing tropical forest and established cattle pasture in the southwestern Brazilian Amazon Basin. High NO(3)(-) concentrations in forest soil solution relative to groundwater indicated a large removal of N mostly as NO(3)(-) in flowpaths leading from soil to groundwater. Forest ground water NO(3)(-) concentrations were lower than in other Amazon sites where riparian zones have been implicated as important N sinks. Based on water budgets for these watersheds, we estimated that 7.3-10.3 kg N ha(-1) y(-1) was removed from flowpaths between 20 and 100 cm, and 7.1-10.2 kg N ha(-1) y(-1) was removed below 100 cm and the top of the groundwater. N removal from vertical flowpaths in forest exceeded previously measured N(2)O emissions of 3.0 kg N ha(-1) y(-1) and estimated emissions of NO of 1.4 kg N ha(-1) y(-1). Potential fates for this large amount of nitrate removal in forest soils include plant uptake, denitrification, and abiotic N retention. Conversion to pasture shifted the system from dominance by processes producing and consuming NO(3)(-) to one dominated by NH(4)(+), presumably the product of lower rates of net N mineralization and net nitrification in pasture compared with forest. In pasture, no hydrological flowpaths contained substantial amounts of NO(3)(-) and estimated N removal from soil vertical flowpaths was 0.2 kg N ha(-1) y(-1) below the depth of 100 cm. This contrasts with the extent to which agricultural sources dominate N inputs to groundwater and stream water in many temperate regions. This could change, however, if pasture agriculture in the tropics shifts toward intensive crop cultivation. | |||||
BibTeX:
@article{chaves_nitrogen_2009, author = {Chaves, Joaquin and Neill, Christopher and Germer, Sonja and Neto, Sergio Gouveia and Krusche, Alex V. and Bonilla, Adriana Castellanos and Elsenbeer, Helmut}, title = {Nitrogen Transformations in Flowpaths Leading from Soils to Streams in Amazon Forest and Pasture}, journal = {Ecosystems}, year = {2009}, volume = {12}, number = {6}, pages = {961--972}, url = {://WOS:000270339300007 http://www.springerlink.com/content/04455435044u71th/fulltext.pdf}, doi = {https://doi.org/10.1007/s10021-009-9270-4} } |
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Chaves, J., Neill, C., Germer, S., Neto, S.G., Krusche, A. and Elsenbeer, H. | Land management impacts on runoff sources in small Amazon watersheds | 2008 | Hydrological Processes Vol. 22(12), pp. 1766-1775 |
article | DOI URL |
Abstract: Forest clearing and conversion to cattle pasture in the lowland Amazon region has been linked to soil compaction and increased soil water storage, which combine to diminish soil infiltration, enhance quick lateral flows and increase the stream flow response to precipitation. Quantifying the importance of quick surficial flow in response to this land use change requires identification of water sources within catchments that contribute to stream flow. Using an end member mixing analysis approach, potential contributing sources of stream flow were evaluated during an entire rainy season in a forest and a pasture watershed drained by ephemeral-to-intermittent streams in the south-western Amazon. Water yield was 17% of precipitation in the pasture and 0.8% of precipitation in the forest. During the early rainy season, throughfall, groundwater, and soil water contributed 79%, 18%, and 3%, respectively, to total forest stream flow. Over the entire rainy season, throughfall, groundwater, and shallow soil water provided 57%, 24%, and 19%, respectively, of stream flow. In the pasture watershed, overland flow dominated stream flow both in the early (67%) and late (57%) rainy season, with a mean contribution of 60% overland flow, 35% groundwater, and 5% soil water. The uncertainty associated with those estimates was studied using a Monte Carlo approach. In addition to large changes in total surface flow, marked differences were found in the proportions of total stream flow in the second half of the rainy season between the forest and pasture watershed. These results suggest that (1) there is great potential for alteration of the hydrological budgets of larger watersheds as the proportion of deforested land in the Amazon increases, and (2) as more rainfall is diverted into fast flowpaths to streams in established pastures, the potential to deliver water with higher solute concentrations generated by erosion or by bypassing sites of solute removal increases. Copyright (c) 2007 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{chaves_land_2008, author = {Chaves, Joaquin and Neill, Christopher and Germer, Sonja and Neto, Sergio Gouveia and Krusche, Alex and Elsenbeer, Helmut}, title = {Land management impacts on runoff sources in small Amazon watersheds}, journal = {Hydrological Processes}, year = {2008}, volume = {22}, number = {12}, pages = {1766--1775}, url = {://WOS:000256958700004 http://onlinelibrary.wiley.com/store/10.1002/hyp.6803/asset/6803_ftp.pdf?v=1&t=h6hyp3a8&s=992ea59300b845a902f7751672f27d1d79dbb903}, doi = {https://doi.org/10.1002/hyp.6803} } |
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Chave, J., Navarrete, D., Almeida, S., Alvarez, E., Aragao, L.E.O.C., Bonal, D., Chatelet, P., Silva-Espejo, J.E., Goret, J.Y., von Hildebrand, P., Jimenez, E., Patino, S., Penuela, M.C., Phillips, O.L., Stevenson, P. and Malhi, Y. | Regional and seasonal patterns of litterfall in tropical South America | 2010 | Biogeosciences Vol. 7(1), pp. 43-55 |
article | DOI URL |
Abstract: The production of aboveground soft tissue represents an important share of total net primary production in tropical rain forests. Here we draw from a large number of published and unpublished datasets (n=81 sites) to assess the determinants of litterfall variation across South American tropical forests. We show that across old-growth tropical rainforests, litterfall averages 8.61 +/- 1.91 Mg ha(-1) yr(-1) (mean +/- standard deviation, in dry mass units). Secondary forests have a lower annual litterfall than old-growth tropical forests with a mean of 8.01 +/- 3.41 Mg ha(-1) yr(-1). Annual litterfall shows no significant variation with total annual rainfall, either globally or within forest types. It does not vary consistently with soil type, except in the poorest soils (white sand soils), where litterfall is significantly lower than in other soil types (5.42 +/- 1.91 Mg ha(-1) yr(-1)). We also study the determinants of litterfall seasonality, and find that it does not depend on annual rainfall or on soil type. However, litterfall seasonality is significantly positively correlated with rainfall seasonality. Finally, we assess how much carbon is stored in reproductive organs relative to photosynthetic organs. Mean leaf fall is 5.74 +/- 1.83 Mg ha(-1) yr(-1) (71% of total litterfall). Mean allocation into reproductive organs is 0.69 +/- 0.40 Mg ha(-1) yr(-1) (9% of total litterfall). The investment into reproductive organs divided by leaf litterfall increases with soil fertility, suggesting that on poor soils, the allocation to photosynthetic organs is prioritized over that to reproduction. Finally, we discuss the ecological and biogeochemical implications of these results. | |||||
BibTeX:
@article{chave_regional_2010, author = {Chave, J. and Navarrete, D. and Almeida, S. and Alvarez, E. and Aragao, L. E. O. C. and Bonal, D. and Chatelet, P. and Silva-Espejo, J. E. and Goret, J. Y. and von Hildebrand, P. and Jimenez, E. and Patino, S. and Penuela, M. C. and Phillips, O. L. and Stevenson, P. and Malhi, Y.}, title = {Regional and seasonal patterns of litterfall in tropical South America}, journal = {Biogeosciences}, year = {2010}, volume = {7}, number = {1}, pages = {43--55}, url = {://WOS:000274058100004 http://www.biogeosciences.net/7/43/2010/bg-7-43-2010.pdf}, doi = {https://doi.org/10.5194/Bg-7-43-2010} } |
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Chave, J., Muller-Landau, H.C., Baker, T.R., Easdale, T.A., Ter Steege, H. and Webb, C.O. | Regional and phylogenetic variation of wood density across 2456 neotropical tree species | 2006 | Ecological Applications Vol. 16(6), pp. 2356-2367 |
article | DOI URL |
Abstract: Wood density is a crucial variable in carbon accounting programs of both secondary and old-growth tropical forests. It also is the best single descriptor of wood: it correlates with numerous morphological, mechanical, physiological, and ecological properties. To explore the extent to which wood density could be estimated for rare or poorly censused taxa, and possible sources of variation in this trait, we analyzed regional, taxonomic, and phylogenetic variation in wood density among 2456 tree species from Central and South America. Wood density varied over more than one order of magnitude across species, with an overall mean of 0.645 g/cm(3). Our geographical analysis showed significant decreases in wood density with increasing altitude and significant differences among low-altitude geographical regions: wet forests of Central America and western Amazonia have significantly lower mean wood density than dry forests of Central and South America, eastern and central Amazonian forests, and the Atlantic forests of Brazil; and eastern Amazonian forests have lower wood densities than the dry forests and the Atlantic forest. A nested analysis of variance showed that 74% of the species-level wood density variation was explained at the genus level, 34% at the Angiosperm Phylogeny Group (APG) family level, and 19% at the APG order level. This indicates that genus-level means give reliable approximations of values of species, except in a few hypervariable genera. We also studied which evolutionary shifts in wood density occurred in the phylogeny of seed plants using a composite phylogenetic tree. Major changes were observed at deep nodes (Eurosid 1), and also in more recent divergences (for instance in the Rhamnoids, Simaroubaceae, and Anacardiaceae). Our unprecedented wood density data set yields consistent guidelines for estimating wood densities when species-level information is lacking and should significantly reduce error in Central and South American carbon accounting programs. | |||||
BibTeX:
@article{chave_regional_2006, author = {Chave, Jerome and Muller-Landau, Helene C. and Baker, Timothy R. and Easdale, Tomas A. and Ter Steege, Hans and Webb, Campbell O.}, title = {Regional and phylogenetic variation of wood density across 2456 neotropical tree species}, journal = {Ecological Applications}, year = {2006}, volume = {16}, number = {6}, pages = {2356--2367}, note = {Edition: 2007/01/09}, url = {://WOS:000242849300024 http://www.esajournals.org/doi/pdf/10.1890/1051-0761%282006%29016%5B2356%3ARAPVOW%5D2.0.CO%3B2}, doi = {https://doi.org/10.1890/1051-0761(2006)016%5B2356:rapvow%5D2.0.co;2} } |
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Chavana-Bryant, C., Malhi Wu, J.Y., Asner, G., Anastasiou, A., Enquist, B., Caravasi, C., Eric, G., Doughty, C., Saleska, S. and Martin, R. | Leaf aging of Amazonian canopy trees as revealed by spectral and physiochemical measurements [BibTeX] |
2016 | New Phytologist (online early) | article | |
BibTeX:
@article{chavana-bryant_leaf_2016, author = {Chavana-Bryant, C. and Malhi, Wu, J., Y. and Asner, G.P. and Anastasiou, A. and Enquist, B.J. and Caravasi, C. and Eric, G. and Doughty, C.E. and Saleska, S.R. and Martin, R.E.}, title = {Leaf aging of Amazonian canopy trees as revealed by spectral and physiochemical measurements}, journal = {New Phytologist (online early)}, year = {2016} } |
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Chapman, B., Siqueira, P. and Freeman, A. | The JERS Amazon Multi-season Mapping Study (JAMMS): observation strategies and data characteristics | 2002 | International Journal of Remote Sensing Vol. 23(7), pp. 1427-1446 |
article | DOI URL |
Abstract: The Japanese Earth Resources Satellite (JERS-1) Amazon Multiseason Mapping Study (JAMMS), part of the Global Rain Forest Mapping (GRFM) project led by the National Space Development Agency of Japan (NASDA), had an ambitious agenda to map the entire Amazon river floodplain (and surrounding areas) twice at high resolution. The observation strategy carried out by NASDA for the JAMMS project and the other elements of the GRFM project (1995-1997) constituted the first time that a spaceborne Synthetic Aperture Radar (SAR) successfully implemented a continental scale, coordinated seasonal mapping campaign. This observation strategy, chosen around the flooding cycle of the major river systems, was designed to provide the first high-resolution measurement of inundation extent by the Amazon river and its tributaries. In order for the scientific community at large to be able to exploit this dataset, the characteristics of the data (resolution, radiometric and geometric calibration, coverage, and ability to be mosaicked) must be well understood. We find that the quantization of the Alaska SAR Facility (ASF) imagery impacts the range of backscatter values that may be observed, in contrast to the NASDA processed imagery. The noise equivalent sigma(0) is -15 dB at worst, but improves to about -20 dB at the centre of the swath. The resolution of the ASF imagery is slightly worse than that processed by NASDA. The initial geolocation accuracy of the ASF processed imagery is quite poor, but may be improved during the mosaicking process. The relative radiometric calibration of the data may be improved to about 0.2 dB by comparing the calibration of overlapping imagery, and through a careful analysis of cross-track trends in the data. | |||||
BibTeX:
@article{chapman_jers_2002, author = {Chapman, B. and Siqueira, P. and Freeman, A.}, title = {The JERS Amazon Multi-season Mapping Study (JAMMS): observation strategies and data characteristics}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {7}, pages = {1427--1446}, url = {://WOS:000174661900012}, doi = {https://doi.org/10.1080/01431160110092966} } |
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Chapelon, N., Douville, H., Kosuth, P. and Oki, T. | Off-line simulation of the Amazon water balance: a sensitivity study with implications for GSWP | 2002 | Climate Dynamics Vol. 19(2), pp. 141-154 |
article | DOI URL |
Abstract: As a first step of the international Global Soil Wetness Project (GSWP), several state-of-the-art land surface models were recently forced by 1degrees x 1degrees atmospheric analyses and observations to obtain global soil moisture climatologies over the 1987-1988 period, Besides the 6-hourly atmospheric forcing. the models also used common boundary conditions (soil and vegetation parameters), also drawn from the ISLSCP Initiative I dataset. While very few in situ observations are available to validate the soil moisture fields, the simulated runoff can be compared with river discharge measurements. This strategy is employed here to assess the quality of GSWP simulations based on the ISBA land surface model. The ISBA runoff is transformed into 10 x to gridded stream flows by using the TRIP river routing model. The focus is on the Amazon basin where all models participating in GSWP showed a strong underestimation in the annual runoff and a significant lag in the annual cycle of the runoff. A sample of 31 gauging stations is selected to validate the gridded runoff simulated by ISBA. Sensitivity tests have been performed, that suggest that deficiencies in both the precipitation forcing and the boundary conditions provided by ISLSCP contribute to the poor simulation of the Amazon water balance. The use of alternative precipitation, soil and vegetation datasets allows ISBA to produce a more realistic annual runoff, although the amplitude of the annual cycle remains exaggerated at the downstream gauging station of Obidos. Among these experiments, the simulation leading to the best annual runoff has been used as a reference to test simple modifications in the TRIP river routing model. Tuning the parameters of TRIP or increasing the resolution of the river channel network is not sufficient to improve the annual cycle of the simulated discharge. New developments are necessary to deal more explicitly with the floodplain inundation that occurs during the rainy season over the Amazon basin, and to derive a geographically variable and time-evolving stream flow velocity. In future, considerable efforts are needed to provide more reliable global land surface and forcing datasets in the continuation of GSWP, in order to validate more efficiently the land surface models and thereby to produce more realistic soil moisture climatologies. | |||||
BibTeX:
@article{chapelon_off-line_2002, author = {Chapelon, N. and Douville, H. and Kosuth, P. and Oki, T.}, title = {Off-line simulation of the Amazon water balance: a sensitivity study with implications for GSWP}, journal = {Climate Dynamics}, year = {2002}, volume = {19}, number = {2}, pages = {141--154}, url = {://WOS:000176930500003 http://www.springerlink.com/content/ajkew67lq8c5gajr/fulltext.pdf}, doi = {https://doi.org/10.1007/s00382-001-0213-9} } |
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Chao, K.-J., Phillips, O.L., Monteagudo, A., Torres-Lezama, A. and Vasquez Martinez, R. | How do trees die? Mode of death in northern Amazonia | 2009 | Journal of Vegetation Science Vol. 20(2), pp. 260-268 |
article | DOI URL |
Abstract: How do trees die in high-mortality and low-mortality Amazonian forest regions? Why do trees die in different ways? Humid, lowland forests in Amazonian Peru and Venezuela. Patterns of multiple treefall and mode of death (standing, broken or uprooted) were recorded for trees textgreater= 10 cm in diameter in permanent plots. Logistic regression was used to relate mode of death to tree diameter, relative growth rate and wood density. Frequency of multiple death events was higher in high-mortality northwestern (NW) than in low-mortality northeastern (NE) Amazonia, but these events were small, averaging two trees killed per multiple death event. Breakage was the dominant known mode of death (51 +/- 8%) in the NW, with half of fatal breakages caused by other treefalls or breakages. Small and slow-growing trees were more prone to breaking than uprooting. In NE Amazonia, the dominant known mode of death was standing (48 +/- 10%); these trees tended to be relatively large and slow growing. Broken trees in NE forests have a lower wood density than uprooted trees. The major mortality mechanisms differ in the two regions. In the NW it involves an interaction between physiological failure and mechanical failure (small size, slow growth and broken mode). In the NE it is mainly driven by physiological failure (large size, slow growth and standing mode). We propose that by creating different-sized gaps the different dominant modes of death would favour species from different functional groups and so help to maintain the contrasting functional composition and mortality rates of the two regions. | |||||
BibTeX:
@article{chao_how_2009, author = {Chao, Kuo-Jung and Phillips, Oliver L. and Monteagudo, Abel and Torres-Lezama, Armando and Vasquez Martinez, Rodolfo}, title = {How do trees die? Mode of death in northern Amazonia}, journal = {Journal of Vegetation Science}, year = {2009}, volume = {20}, number = {2}, pages = {260--268}, url = {://WOS:000264568200008 http://onlinelibrary.wiley.com/store/10.1111/j.1654-1103.2009.05755.x/asset/j.1654-1103.2009.05755.x.pdf?v=1&t=h6hynki1&s=331369edbac93ed51f12eb2b3fb1516b572426df}, doi = {https://doi.org/10.1111/j.1654-1103.2009.05755.x} } |
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Chao, K.-J., Phillips, O.L., Gloor, E., Monteagudo, A., Torres-Lezama, A. and Vasquez Martinez, R. | Growth and wood density predict tree mortality in Amazon forests | 2008 | Journal of Ecology Vol. 96(2), pp. 281-292 |
article | DOI URL |
Abstract: 1. Tree mortality is an important process in forest ecology. We explored the extent to which tropical tree death is a predictable outcome of taxon and individual level properties by means of mixed-species logistic regression, for trees textgreater= 10 cm in diameter. We worked in two lowland forest regions with markedly different floristic composition and dynamic regimes - the high wood density, low-mortality northeastern (NE) Amazon (in eastern Venezuela), and the low wood density, high-mortality northwestern (NW) Amazon (in northern Peru). 2. Among those genera that are shared between regions there were no detectable regional differences in mortality rates. This suggests that floristic compositional differences are a major driver of the twofold regional contrast in stand-level mortality. 3. In NE forests, mortality risk of individual trees is best predicted by low taxon-level wood density, slow relative growth, and large size, reflecting phylogenetically determined life-history strategy, physiological stress and senescence. 4. In NW forests, trees with low wood density and slow relative growth are also at most risk, but probability of death is independent of tree size, indicating that senescence is unimportant in this region. 5. Synthesis. This study shows that despite fundamental floristic and dynamic differences between the two Amazonian regions, mortality risk can be predicted with mixed-species, individual-based statistical models and that the predictors are remarkably similar, such that tree growth and wood density both play important roles. | |||||
BibTeX:
@article{chao_growth_2008, author = {Chao, Kuo-Jung and Phillips, Oliver L. and Gloor, Emanuel and Monteagudo, Abel and Torres-Lezama, Armando and Vasquez Martinez, Rodolfo}, title = {Growth and wood density predict tree mortality in Amazon forests}, journal = {Journal of Ecology}, year = {2008}, volume = {96}, number = {2}, pages = {281--292}, url = {://WOS:000252899300005 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2745.2007.01343.x/asset/j.1365-2745.2007.01343.x.pdf?v=1&t=h6hyn8x3&s=fff7d23bc31eed68aa62c4c163e21a8676d903dc}, doi = {https://doi.org/10.1111/j.1365-2745.2007.01343.x} } |
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Chao, K.-J., Phillips, O.L. and Baker, T.R. | Wood density and stocks of coarse woody debris in a northwestern Amazonian landscape | 2008 | Canadian Journal of Forest Research-Revue Canadienne De Recherche Forestiere Vol. 38(4), pp. 795-805 |
article | DOI URL |
Abstract: Coarse woody debris (CWD) is a rarely studied component of the carbon cycle. We report the first measurements of both CWD wood density and necromass in humid, lowland northwestern Amazonia, using both line-intersect and plot-based methods. Average CWD densities were not significantly different between clay-rich and white sand unflooded forests, but lower in floodplain forest (p textless= 0.001). Necromass of CWD lying on the ground was also lower in the floodplain (10.3 +/- 6.1 Mg.ha(-1), mean +/- 1 SE) than in the clay-rich (30.9 +/- 5.4) and white sand (45.8 +/- 7.3) forests (p textless= 0.001, using the line-intersect method). These patterns are likely driven by disturbance history, species composition, and decomposition rates. Plot-based data showed that standing and fallen CWD together accounted for 6.4%-15.4% of total coarse aboveground vegetative mass (trees textgreater= 10 cm diameter). Across humid, lowland neotropical forests, we show that wood densities of intact and partially decayed CWD are significantly related with live wood density at the same site (p = 0.026 and 0.003, respectively). We show that these relationships can be applied generally to estimate CWD wood density for humid, lowland neotropical forests wherever destructive sampling is not possible. | |||||
BibTeX:
@article{chao_wood_2008, author = {Chao, Kuo-Jung and Phillips, Oliver L. and Baker, Timothy R.}, title = {Wood density and stocks of coarse woody debris in a northwestern Amazonian landscape}, journal = {Canadian Journal of Forest Research-Revue Canadienne De Recherche Forestiere}, year = {2008}, volume = {38}, number = {4}, pages = {795--805}, url = {://WOS:000256119600014 http://www.nrcresearchpress.com/doi/abs/10.1139/X07-163}, doi = {https://doi.org/10.1139/x07-163} } |
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Chao, K.J., Phillips, O.L., Baker, T.R., Peacock, J., Lopez-Gonzalez, G., Vasquez Martinez, R., Monteagudo, A. and Torres-Lezama, A. | After trees die: quantities and determinants of necromass across Amazonia | 2009 | Biogeosciences Vol. 6(8), pp. 1615-1626 |
article | URL |
Abstract: The Amazon basin, one of the most substantial biomass carbon pools on earth, is characterised by strong macroecological gradients in biomass, mortality rates, and wood density from west to east. These gradients could affect necromass stocks, but this has not yet been tested. This study aims to assess the stocks and determinants of necromass across Amazonian forests. Field-based and literature data were used to find relationships between necromass and possible determinants. Furthermore, a simple model was applied to estimate and extrapolate necromass stocks across terra firma Amazonian forests. In eight northwestern and three northeastern Amazonian permanent plots, volumes of coarse woody debris (textgreater= 10 cm diameter) were measured in the field and the density of each decay class was estimated. Forest structure and historical mortality data were used to determine the factors controlling necromass. Necromass is greater in forests with low stem mortality rates (northeast) rather than in forests with high stem mortality rates (northwest) (58.5 +/- 10.6 and 27.3 +/- 3.2 Mg ha(-1), respectively). Using all published necromass values, we find that necromass across terra firma forests in Amazonia is positively related to both forest dynamics (mortality mass inputs and a surrogate for decomposition rate (average wood density of living trees)) and forest structure (biomass), but is better explained by forest dynamics. We propose an improved method to estimate necromass for plots where necromass has not been measured. The estimates, together with other actual measurements of necromass, were scaled-up to project a total Amazonian necromass of 9.6 +/- 1.0 Pg C. The ratio of necromass (on average weighted by forest region) to coarse above-ground biomass is 0.127. Overall, we find (1) a strong spatial trend in necromass in parallel with other macroecological gradients and (2) that necromass is a substantial component of the carbon pool in the Amazon. | |||||
BibTeX:
@article{chao_after_2009, author = {Chao, K. J. and Phillips, O. L. and Baker, T. R. and Peacock, J. and Lopez-Gonzalez, G. and Vasquez Martinez, R. and Monteagudo, A. and Torres-Lezama, A.}, title = {After trees die: quantities and determinants of necromass across Amazonia}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {8}, pages = {1615--1626}, url = {://WOS:000269405000017} } |
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Chand, D., Guyon, P., Artaxo, P., Schmid, O., Frank, G.P., Rizzo, L.V., Mayol-Bracero, O.L., Gatti, L.V. and Andreae, M.O. | Optical and physical properties of aerosols in the boundary layer and free troposphere over the Amazon Basin during the biomass burning season | 2006 | Atmospheric Chemistry and Physics Vol. 6, pp. 2911-2925 |
article | URL |
Abstract: As part of the Large Scale Biosphere-Atmosphere Experiment in Amazonia - Smoke, Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) campaign, detailed surface and airborne aerosol measurements were performed over the Amazon Basin during the dry to wet season from 16 September to 14 November 2002. Optical and physical properties of aerosols at the surface, and in the boundary layer (BL) and free troposphere (FT) during the dry season are discussed in this article. Carbon monoxide (CO) is used as a tracer for biomass burning emissions. At the surface, good correlation among the light scattering coefficient (sigma(s) at 545 nm), PM2.5, and CO indicates that biomass burning is the main source of aerosols. Accumulation of haze during some of the large-scale biomass burning events led to high PM2.5 (225 mu g m(-3)), sigma(s) (1435Mm(-1)), aerosol optical depth at 500 nm (3.0), and CO (3000 ppb). A few rainy episodes reduced the PM2.5, number concentration (CN) and CO concentration by two orders of magnitude. The correlation analysis between sigma(s) and aerosol optical thickness shows that most of the optically active aerosols are confined to a layer with a scale height of 1617 m during the burning season. This is confirmed by aircraft profiles. The average mass scattering and absorption efficiencies (545 nm) for small particles (diameter D-p textless 1.5 mu m) at surface level are found to be 5.0 and 0.33 m(2) g(-1), respectively, when relating the aerosol optical properties to PM2.5 aerosols. The observed mean single scattering albedo (omega(0) at 545 nm) for submicron aerosols at the surface is 0.92 +/- 0.02. The light scattering by particles (Delta sigma(s)/1 Delta CN) increase 2-10 times from the surface to the FT, most probably due to the combined affects of coagulation and condensation. | |||||
BibTeX:
@article{chand_optical_2006, author = {Chand, D. and Guyon, P. and Artaxo, P. and Schmid, O. and Frank, G. P. and Rizzo, L. V. and Mayol-Bracero, O. L. and Gatti, L. V. and Andreae, M. O.}, title = {Optical and physical properties of aerosols in the boundary layer and free troposphere over the Amazon Basin during the biomass burning season}, journal = {Atmospheric Chemistry and Physics}, year = {2006}, volume = {6}, pages = {2911--2925}, url = {://WOS:000239035900001} } |
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Chamecki, M., Freire, L.S., Dias, N.L., Chen, B., Dias-Junior, C.Q., Toledo Machado, L.A., Sörgel, M., Tsokankunku, A. and Araújo, A.C.d. | Effects of Vegetation and Topography on the Boundary Layer Structure above the Amazon Forest [BibTeX] |
2020 | Journal of the Atmospheric Sciences Vol. 77(8), pp. 2941-2957 |
article | DOI URL |
BibTeX:
@article{chamecki_effects_2020, author = {Chamecki, Marcelo and Freire, Livia S. and Dias, Nelson L. and Chen, Bicheng and Dias-Junior, Cléo Quaresma and Toledo Machado, Luiz Augusto and Sörgel, Matthias and Tsokankunku, Anywhere and Araújo, Alessandro C. de}, title = {Effects of Vegetation and Topography on the Boundary Layer Structure above the Amazon Forest}, journal = {Journal of the Atmospheric Sciences}, year = {2020}, volume = {77}, number = {8}, pages = {2941--2957}, url = {https://journals.ametsoc.org/view/journals/atsc/77/8/jasD200063.xml}, doi = {https://doi.org/10.1175/jas-d-20-0063.1} } |
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Chamecki, M., Dias, N. and Freire, L. | A TKE‐Based Framework for Studying Disturbed Atmospheric Surface Layer Flows and Application to Vertical Velocity Variance Over Canopies [BibTeX] |
2018 | Geophysical Research Letters Vol. 45(13), pp. 6734-6740 |
article | DOI |
BibTeX:
@article{chamecki_tkebased_2018, author = {Chamecki, M. and Dias, N.L. and Freire, L.S.}, title = {A TKE‐Based Framework for Studying Disturbed Atmospheric Surface Layer Flows and Application to Vertical Velocity Variance Over Canopies}, journal = {Geophysical Research Letters}, year = {2018}, volume = {45}, number = {13}, pages = {6734--6740}, doi = {https://doi.org/10.1029/2018GL077853} } |
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Chambers, J.Q., Tribuzy, E.S., Toledo, L.C., Crispim, B.F., Higuchi, N., dos Santos, J., Araujo, A.C., Kruijt, B., Nobre, A.D. and Trumbore, S.E. | Respiration from a tropical forest ecosystem: Partitioning of sources and low carbon use efficiency | 2004 | Ecological Applications Vol. 14(4), pp. S72-S88 |
article | URL |
Abstract: Understanding how tropical forest carbon balance will respond to global change requires knowledge of individual heterotrophic and autotrophic respiratory sources, together with factors that control respiratory variability. We measured leaf, live wood, and soil respiration, along with additional environmental factors over a 1-yr period in a Central Amazon terra firme forest. Scaling these fluxes to the ecosystem, and combining our data with results from other studies, we estimated an average total ecosystem respiration (R-eco) of 7.8 mumol(.)m(-2.)s(-1). Average estimates (per unit ground area) for leaf, wood, soil, total heterotrophic, and total autotrophic respiration were 2.6, 1.1, 3.2, 5.6, and 2.2 mumol(.)m(-2.)s(-1), respectively. Comparing autotrophic respiration with net primary production (NPP) estimates indicated that only similar to30% of carbon assimilated in photosynthesis was used to construct new tissues, with the remaining 70% being respired back to the atmosphere as autotrophic respiration. This low ecosystem carbon use efficiency (CUE) differs considerably from the relatively constant CUE of similar to0.5 found for temperate forests. Our R-eco estimate was comparable to the above-canopy flux (F-ac) from eddy covariance during defined sustained high turbulence conditions (when presumably F-ac = R-eco) of 8.4 (95% CI = 7.59.4). Multiple regression analysis demonstrated that similar to50% of the nighttime variability in Fa, was accounted for by friction velocity (u*, a measure of turbulence) variables. After accounting for u* variability, mean F-ac varied significantly with seasonal and daily changes in precipitation. A seasonal increase in precipitation resulted in a decrease in F-ac similar to our soil respiration response to moisture. The effect of daily changes in precipitation was complex: precipitation after a dry period resulted in a large increase in F-ac whereas additional precipitation after a rainy period had little effect. This response was similar to that of surface litter (coarse and fine), where respiration is greatly reduced when moisture is limiting, but increases markedly and quickly saturates with an increase in moisture. | |||||
BibTeX:
@article{chambers_respiration_2004, author = {Chambers, J. Q. and Tribuzy, E. S. and Toledo, L. C. and Crispim, B. F. and Higuchi, N. and dos Santos, J. and Araujo, A. C. and Kruijt, B. and Nobre, A. D. and Trumbore, S. E.}, title = {Respiration from a tropical forest ecosystem: Partitioning of sources and low carbon use efficiency}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S72--S88}, url = {://WOS:000223269000008} } |
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Chambers, J.Q. and Silver, W.L. | Some aspects of ecophysiological and biogeochemical responses of tropical forests to atmospheric change | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 463-476 |
article | DOI URL |
Abstract: Atmospheric changes that may affect physiological and biogeochemical processes in old-growth tropical forests include: (i) rising atmospheric CO2 concentrations; (ii) an increase in land surface temperature; (iii) changes in precipitation and ecosystem moisture status; and (iv) altered disturbance regimes. Elevated CO2 is likely to directly influence numerous leaf-level physiological processes, but whether these changes are ultimately reflected in altered ecosystem carbon storage is unclear. The net primary productivity (NPP) response of old-growth tropical forests to elevated CO2 is unknown, but unlikely to exceed the maximum experimentally measured 25% increase in NPP with a doubling of atmospheric CO2 from pre-industrial levels. In addition, evolutionary constraints exhibited by tropical plants adapted to low CO2 levels during most of the Late Pleistocene, may result in little response to increased carbon availability. To set a maximum potential response for a Central Amazon forest, using an individual-tree-based carbon cycling model, a modelling experiment was performed constituting a 25% increase in tree growth rate, linked to the known and expected increase in atmospheric CO2. Results demonstrated a maximum carbon sequestration rate of ca. 0.2 Mg C per hectare per year (ha(-1) yr(-1), where 1 ha = 10(4) m(2)), and a sequestration rate of only 0.05 Mg C ha(-1) yr(-1) for an interval centred on calendar years 1980-2020. This low rate results from slow growing trees and the long residence time of carbon in woody tissues. By contrast, changes in disturbance frequency, precipitation patterns and other environmental factors can cause marked and relatively rapid shifts in ecosystem carbon storage. It is our view that observed changes in tropical forest inventory plots over the past few decades is more probably being driven by changes in disturbance or other environmental factors, than by a response to elevated CO2. Whether these observed changes in tropical forests are the beginning of long-term permanent shifts or a transient response is uncertain and remains an important research priority. | |||||
BibTeX:
@article{chambers_aspects_2004, author = {Chambers, J. Q. and Silver, W. L.}, title = {Some aspects of ecophysiological and biogeochemical responses of tropical forests to atmospheric change}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {463--476}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100011 http://rstb.royalsocietypublishing.org/content/359/1443/463.full.pdf}, doi = {https://doi.org/10.1098/rstb.2003.1424} } |
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Chambers, J.Q., Schimel, J.P. and Nobre, A.D. | Respiration from coarse wood litter in central Amazon forests | 2001 | Biogeochemistry Vol. 52(2), pp. 115-131 |
article | DOI URL |
Abstract: Respiration from coarse litter (trunks and large branches textgreater 10 cm diameter) was studied in central Amazon forests. Respiration rates varied over almost two orders of magnitude (1.003-0.014 mug C g(-1) C min(-1), n = 61), and were significantly correlated with wood density (r(adj)(2) = 0.42), and moisture content (r(adj)(2) = 0.39). Additional samples taken from a nearby pasture indicated that wood moisture content was the most important factor controlling respiration rates across sites (r(adj)(2) = 0.65). Based on average coarse litter wood density and moisture content, the mean long-term carbon loss rate due to respiration was estimated to be 0.13 yr(-1) (range of 95% prediction interval (PI) = 0.11-0.15 yr(-1)). Comparing mean respiration rate with mean mass loss (decomposition) rate from a previous study, respiratory emissions to the atmosphere from coarse litter were predicted to be 76% (95% PI = 65-88%) of total carbon loss, or about 1.9 (95% PI = 1.6-2.2) Mg C ha(-1) yr(-) (1). Optimum respiration activity corresponded to about 2.5 g H2O g(-1) dry wood, and severely restricted respiration to textless 0.5 g H2O g(-1) dry wood. Respiration from coarse litter in central Amazon forests is comparable in magnitude to decomposing fine surface litter (e.g. leaves, twigs) and is an important carbon cycling component when characterizing heterotrophic respiration budgets and net ecosystem exchange (NEE). | |||||
BibTeX:
@article{chambers_respiration_2001, author = {Chambers, J. Q. and Schimel, J. P. and Nobre, A. D.}, title = {Respiration from coarse wood litter in central Amazon forests}, journal = {Biogeochemistry}, year = {2001}, volume = {52}, number = {2}, pages = {115--131}, url = {://WOS:000166353200001 http://www.springerlink.com/content/n312lm0005258u05/fulltext.pdf}, doi = {https://doi.org/10.1023/a:1006473530673} } |
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Chambers, J.Q., Robertson, A.L., Carneiro, V.M.C., Lima, A.J.N., Smith, M.-L., Plourde, L.C. and Higuchi, N. | Hyperspectral remote detection of niche partitioning among canopy trees driven by blowdown gap disturbances in the Central Amazon | 2009 | Oecologia Vol. 160(1), pp. 107-117 |
article | DOI URL |
Abstract: Advanced recruitment and neutral processes play important roles in determining tree species composition in tropical forest canopy gaps, with few gaps experiencing clear secondary successional processes. However, most studies are limited to the relatively limited spatial scales provided by forest inventory plots, and investigations over the entire range of gap size are needed to better understand how ecological processes vary with tree mortality events. This study employed a landscape approach to test the hypothesis that tree species composition and forest structural attributes differ between large blowdown gaps and relatively undisturbed primary forest. Spectral mixture analysis on hyperspectral satellite imagery was employed to direct field sampling to widely distributed sites, and blowdown plots were compared with undisturbed primary forest plots. Tree species composition and forest structural attributes differed markedly between gap and non-gap sites, providing evidence of niche partitioning in response to disturbance across the region. Large gaps were dominated by classic Neotropical pioneer genera such as Cecropia and Vismia, and average tree size was significantly smaller. Mean wood density of trees recovering in large gaps (0.55 g cm(-3)) was significantly lower than in primary forest plots (0.71 g cm(-3)), a difference similar to that found when comparing less dynamic (i.e., tree recruitment, growth, and mortality) Central Amazon forests with more dynamic Western Amazon forests. Based on results, we hypothesize that the importance of neutral processes weaken, and niche processes strengthen, in determining community assembly along a gradient in gap size and tree mortality intensity. Over evolutionary time scales, pervasive dispersal among colonizers could result in the loss of tree diversity in the pioneer guild through competitive exclusion. Results also underscore the importance of considering disturbance processes across the landscape when addressing forest carbon balance. | |||||
BibTeX:
@article{chambers_hyperspectral_2009, author = {Chambers, Jeffrey Q. and Robertson, Amanda L. and Carneiro, Vilany M. C. and Lima, Adriano J. N. and Smith, Marie-Louise and Plourde, Lucie C. and Higuchi, Niro}, title = {Hyperspectral remote detection of niche partitioning among canopy trees driven by blowdown gap disturbances in the Central Amazon}, journal = {Oecologia}, year = {2009}, volume = {160}, number = {1}, pages = {107--117}, note = {Edition: 2009/02/06}, url = {://WOS:000265100500011 http://www.springerlink.com/content/u677008182315561/fulltext.pdf}, doi = {https://doi.org/10.1007/s00442-008-1274-9} } |
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Chambers, J.Q., Negron-Juarez, R.I., Hurtt, G.C., Marra, D.M. and Higuchi, N. | Lack of intermediate-scale disturbance data prevents robust extrapolation of plot-level tree mortality rates for old-growth tropical forests | 2009 | Ecology Letters Vol. 12(12), pp. E22-E25 |
article | DOI URL |
Abstract: Lloyd et al. (2009) question the methods, concepts and conclusions of Fisher et al. (2008). We address these assertions, and place our work into a broader context. We demonstrate the veracity of Fisher et al., and further show that lack of data for intermediate-scale tree mortality disturbance events for old-growth tropical forests might prevent robust extrapolation of forest plot biomass accumulation data, and accurate estimates of distribution parameters such as power-law exponents (alpha). | |||||
BibTeX:
@article{chambers_lack_2009, author = {Chambers, Jeffrey Q. and Negron-Juarez, Robinson I. and Hurtt, George C. and Marra, Daniel M. and Higuchi, Niro}, title = {Lack of intermediate-scale disturbance data prevents robust extrapolation of plot-level tree mortality rates for old-growth tropical forests}, journal = {Ecology Letters}, year = {2009}, volume = {12}, number = {12}, pages = {E22--E25}, url = {://WOS:000271631500002 http://onlinelibrary.wiley.com/store/10.1111/j.1461-0248.2009.01398.x/asset/j.1461-0248.2009.01398.x.pdf?v=1&t=h6hym4zr&s=15d456fdccea1697411e1e0d4df2a65987f9da58}, doi = {https://doi.org/10.1111/j.1461-0248.2009.01398.x} } |
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Chambers, J.Q., Higuchi, N., Tribuzy, E.S. and Trumbore, S.E. | Carbon sink for a century [BibTeX] |
2001 | Nature Vol. 410(6827), pp. 429-429 |
article | DOI URL |
BibTeX:
@article{chambers_carbon_2001, author = {Chambers, J. Q. and Higuchi, N. and Tribuzy, E. S. and Trumbore, S. E.}, title = {Carbon sink for a century}, journal = {Nature}, year = {2001}, volume = {410}, number = {6827}, pages = {429--429}, note = {Edition: 2001/03/22}, url = {://WOS:000167583800028 http://www.nature.com/nature/journal/v410/n6827/pdf/410429a0.pdf}, doi = {https://doi.org/10.1038/35068624} } |
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Chambers, J.Q., Higuchi, N., Teixeira, L.M., dos Santos, J., Laurance, S.G. and Trumbore, S.E. | Response of tree biomass and wood litter to disturbance in a Central Amazon forest | 2004 | Oecologia Vol. 141(4), pp. 596-611 |
article | DOI URL |
Abstract: We developed an individual-based stochastic-empirical model to simulate the carbon dynamics of live and dead trees in a Central Amazon forest near Manaus, Brazil. The model is based on analyses of extensive field studies carried out on permanent forest inventory plots, and syntheses of published studies. New analyses included: ( 1) growth suppression of small trees, ( 2) maximum size ( trunk base diameter) for 220 tree species, ( 3) the relationship between growth rate and wood density, and ( 4) the growth response of surviving trees to catastrophic mortality ( from logging). The model simulates a forest inventory plot, and tracks recruitment, growth, and mortality of live trees, decomposition of dead trees ( coarse litter), and how these processes vary with changing environmental conditions. Model predictions were tested against aggregated field data, and also compared with independent measurements including maximum tree age and coarse litter standing stocks. Spatial analyses demonstrated that a plot size of similar to 10 ha was required to accurately measure wood ( live and dead) carbon balance. With the model accurately predicting relevant pools and fluxes, a number of model experiments were performed to predict forest carbon balance response to perturbations including: ( 1) increased productivity due to CO2 fertilization, ( 2) a single semi-catastrophic ( 10%) mortality event, ( 3) increased recruitment and mortality ( turnover) rates, and ( 4) the combined effects of increased turnover, increased tree growth rates, and decreased mean wood density of new recruits. Results demonstrated that carbon accumulation over the past few decades observed on tropical forest inventory plots (similar to 0.5 Mg C ha(-1) year(-1)) is not likely caused by CO2 fertilization. A maximum 25% increase in woody tissue productivity with a doubling of atmospheric CO2 only resulted in an accumulation rate of 0.05 Mg C ha(-1) year(-1) for the period 1980 - 2020 for a Central Amazon forest, or an order of magnitude less than observed on the inventory plots. In contrast, model parameterization based on extensive data from a logging experiment demonstrated a rapid increase in tree growth following disturbance, which could be misinterpreted as carbon sequestration if changes in coarse litter stocks were not considered. Combined results demonstrated that predictions of changes in forest carbon balance during the twenty-first century are highly dependent on assumptions of tree response to various perturbations, and underscores the importance of a close coupling of model and field investigations. | |||||
BibTeX:
@article{chambers_response_2004, author = {Chambers, J. Q. and Higuchi, N. and Teixeira, L. M. and dos Santos, J. and Laurance, S. G. and Trumbore, S. E.}, title = {Response of tree biomass and wood litter to disturbance in a Central Amazon forest}, journal = {Oecologia}, year = {2004}, volume = {141}, number = {4}, pages = {596--611}, note = {Edition: 2004/09/15}, url = {://WOS:000224999800006 http://www.springerlink.com/content/8xd512h079fakcxu/fulltext.pdf}, doi = {https://doi.org/10.1007/s00442-004-1676-2} } |
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Chambers, J.Q., Higuchi, N., Schimel, J.P., Ferreira, L.V. and Melack, J.M. | Decomposition and carbon cycling of dead trees in tropical forests of the central Amazon | 2000 | Oecologia Vol. 122(3), pp. 380-388 |
article | DOI URL |
Abstract: Decomposition rare constants were measured for holes of 155 large dead trees (textgreater10 cm diameter) in central Amazon forests. Mortality data from 21 ha of permanent inventory plots, monitored for 10-15 years, were used to select dead trees for sampling. Measured rate constants varied by over 1.5 orders of magnitude (0.015-0.67 year(-1)), averaging 0.19 year(-1) with predicted error of 0.026 year. Wood density and bole diameter were significantly and inversely correlated with rate constants. A tree of average biomass was predicted to decompose at 0.17 year(-1). Based on mortality data, an average of 7.0 trees ha(-1) year(-1) died producing 3.6 Mg ha(-1) year(-1) of coarse litter (textgreater10 cm diameter). Mean coarse litter standing-stocks were predicted to be 21 Mg ha(-1) with a mean residence time of 5.9 years, and a maximum mean carbon flux to the atmosphere of 1.8 Mg C ha(-1) year(-1). Total litter is estimated to be partitioned into 16% fine wood, 30% coarse wood, and 54% non-woody litter (e.g., leaves, fruits, flowers). Decomposition rate constants for coarse litter were compiled from 20 globally distributed studies. Rates were highly correlated with mean annual temperature, giving a respiration quotient (Q(10)) of 2.4 (10 degrees C-1). | |||||
BibTeX:
@article{chambers_decomposition_2000, author = {Chambers, J. Q. and Higuchi, N. and Schimel, J. P. and Ferreira, L. V. and Melack, J. M.}, title = {Decomposition and carbon cycling of dead trees in tropical forests of the central Amazon}, journal = {Oecologia}, year = {2000}, volume = {122}, number = {3}, pages = {380--388}, url = {://WOS:000085943100010 http://www.springerlink.com/content/1xttnhq0lgtv34l8/fulltext.pdf}, doi = {https://doi.org/10.1007/s004420050044} } |
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Chambers, J.Q., dos Santos, J., Ribeiro, R.J. and Higuchi, N. | Tree damage, allometric relationships, and above-ground net primary production in central Amazon forest | 2001 | Forest Ecology and Management Vol. 152(1-3), pp. 73-84 |
article | DOI URL |
Abstract: The loss of tree mass over time from damage can lead to underestimates in above-ground net primary productivity (ANPP) if not accounted for properly. Bias in the allometric relationship between trunk base diameter (D-b, at 1.3 m height or above the buttresses) and mass can also lead to systematic errors in ANPP estimates. We developed an unbiased model of the relationship between D-b and tree mass using data from 315 trees (greater than or equal to5 cm D-b) harvested in the central Amazon. This model was compared with other theoretical (n = 1) and empirical models (n = 4). The theoretical model, and one empirical model, made predictions that differed substantially form our central Amazon model. The other three empirical models made predictions that were consistent with our model despite being developed in different tropical forests. Models differed mostly in predicting large tree mass. Using permanent forest inventory plot data, our D-b versus tree mass model, and a bole volume model, we estimated that tree damage amounts to 0.9 Mg ha(-1) per year (dry mass) of litter production. This damage should be included as a mass loss term when calculating ANPP. Incorporating fine litter data from published studies, we estimated that average ANPP for central Amazon plateau forests is at least 12.9 Mg ha(-1) per year (or 6.5 Mg C ha(-1) per year). Additional sources of error as described in the text can raise this estimate by as much as 4 Mg ha(-1) per year. We hypothesize that tree damage in old-growth forests accounts for a significant portion of age related decline in productivity. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{chambers_tree_2001, author = {Chambers, J. Q. and dos Santos, J. and Ribeiro, R. J. and Higuchi, N.}, title = {Tree damage, allometric relationships, and above-ground net primary production in central Amazon forest}, journal = {Forest Ecology and Management}, year = {2001}, volume = {152}, number = {1-3}, pages = {73--84}, url = {://WOS:000171497800006}, doi = {https://doi.org/10.1016/s0378-1127(00)00591-0} } |
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Chambers, J.Q., Asner, G.P., Morton, D.C., Anderson, L.O., Saatch, S.S., Espirito-Santo, F.D.B., Palace, M. and Souza Jr., C. | Regional ecosystem structure and function: ecological insights from remote sensing of tropical forests | 2007 | Trends in Ecology & Evolution Vol. 22(8), pp. 414-423 |
article | DOI URL |
Abstract: Ecological studies in tropical forests have long been plagued by difficulties associated with sampling the crowns of large canopy trees and large inaccessible regions, such as the Amazon basin. Recent advances in remote sensing have overcome some of these obstacles, enabling progress towards tackling difficult ecological problems. Breakthroughs have helped transform the dialog between ecology and remote sensing, generating new regional perspectives on key environmental gradients and species assemblages with ecologically relevant measures such as canopy nutrient and moisture content, crown area, leaf-level drought responses, woody tissue and surface litter abundance, phenological patterns, and land-cover transitions. Issues that we address here include forest response to altered precipitation regimes, regional disturbance and land-use patterns, invasive species and landscape carbon balance. | |||||
BibTeX:
@article{chambers_regional_2007, author = {Chambers, J. Q. and Asner, G. P. and Morton, D. C. and Anderson, L. O. and Saatch, Sassan S. and Espirito-Santo, Fernando D. B. and Palace, Michael and Souza, Jr., Carlos}, title = {Regional ecosystem structure and function: ecological insights from remote sensing of tropical forests}, journal = {Trends in Ecology & Evolution}, year = {2007}, volume = {22}, number = {8}, pages = {414--423}, note = {Edition: 2007/05/12}, url = {://WOS:000248638100006}, doi = {https://doi.org/10.1016/j.tree.2007.05.001} } |
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Chambers, J. and Artaxo, P. | Biosphere-atmosphere interactions: Deforestation size influences rainfall [BibTeX] |
2017 | Nature Climate Change (Letters) Vol. 73, pp. 175-176 |
article | |
BibTeX:
@article{chambers_biosphere-atmosphere_2017, author = {Chambers, J.Q. and Artaxo, P.}, title = {Biosphere-atmosphere interactions: Deforestation size influences rainfall}, journal = {Nature Climate Change (Letters)}, year = {2017}, volume = {73}, pages = {175--176} } |
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Chambers, J.Q. and Artaxo, P. | Deforestation size influences rainfall [BibTeX] |
2017 | Nature Climate Change | article | |
BibTeX:
@article{chambers_deforestation_2017, author = {Chambers, Jeffrey Q. and Artaxo, Paulo}, title = {Deforestation size influences rainfall}, journal = {Nature Climate Change}, year = {2017} } |
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Chagas Silva, V.d.C.A.d.&.D.V.G. | Impactos da redução da pluviometria na biomassa aérea da Floresta Amazônica [BibTeX] |
2012 | Revista Brasileira de Engenharia Agrícola e Ambiental Vol. 16(1), pp. 72-79 |
article | |
BibTeX:
@article{chagas_impactos_2012, author = {Chagas, Silva, V.P.R. da, Costa, A.C.L. da & Dantas, V.A., G.F.B.}, title = {Impactos da redução da pluviometria na biomassa aérea da Floresta Amazônica}, journal = {Revista Brasileira de Engenharia Agrícola e Ambiental}, year = {2012}, volume = {16}, number = {1}, pages = {72--79} } |
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Cerri, C.E.P., Sparovek, G., Bernoux, M., Easterling, W.E., Melillo, J.M. and Cerri, C.C. | Tropical agriculture and global warming: Impacts and mitigation options | 2007 | Scientia Agricola Vol. 64(1), pp. 83-99 |
article | URL |
Abstract: The intensive land use invariably has several negative effects on the environment and crop production if conservative practices are not adopted. Reduction in soil organic matter (SOM) quantity means gas emission (mainly CO(2), CH(4), N(2)O) to the atmosphere and increased global warming. Soil sustainability is also affected, since remaining SOM quality changes. Alterations can be verified, for example, by soil desegregation and changes in structure. The consequences are erosion, reduction in nutrient availability for the plants and lower water retention capacity. These and other factors reflect negatively on crop productivity and sustainability of the soil -plant-atmosphere system. Conversely, adoption of "best management practices", such as conservation tillage, can partly reverse the process - they are aimed at increasing the input of organic matter to the soil and/or decreasing the rates at which soil organic matter decomposes. | |||||
BibTeX:
@article{cerri_tropical_2007, author = {Cerri, Carlos Eduardo P. and Sparovek, Gerd and Bernoux, Martial and Easterling, Willian E. and Melillo, Jerry M. and Cerri, Carlos Clemente}, title = {Tropical agriculture and global warming: Impacts and mitigation options}, journal = {Scientia Agricola}, year = {2007}, volume = {64}, number = {1}, pages = {83--99}, url = {://WOS:000244736100013} } |
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Cerri, C.E.P., Piccolo, M.C., Feigl, B.J., Paustian, K., Cerri, C.C., Victoria, R.L. and Melillo, J.M. | Interrelationships among soil total C and N, microbial biomass, trace gas fluxes, and internal N-cycling in soils under pasture of the Amazon region | 2006 | Journal of Sustainable Agriculture Vol. 27(4), pp. 45-69 |
article | DOI URL |
Abstract: The aim of this study was to investigate the interrelationships and seasonal weather variations on soil total C and N concentrations, microbial biomass C pool, trace gas fluxes, and rates of internal N-cycling from soils under degraded pasture at Nova Vida ranch, Rondonia, Brazilian Amazon. We collected samples from soils and gas fluxes at the 5 soil types in April 2000 (end of the wet season) and in October 2001 (end of the dry season). Samples were analyzed in both seasons for soil microbial biomass C, soil total C and N, inorganic N, net N mineralization and net nitrification rates and some other soil properties. Overall, the effects of the season events upon soil properties were highly variable. The studied soils with high rates of CO, evolution but low rates of net N mineralization had high rates of N immobilization. The high immobilization rates suggest that the high CO2 evolution rates were associated with a growing microbial biomass. Moreover, in the wet season, the lower NO3--N pools and rates of net mineralization and net nitrification we measured are indicative of lower pasture N2O fluxes. In general, net nitrification rates exceeded net N mineralization rates as the relatively NH4+-N pools. The interrelationships were investigated in order to understand the major biogeochemical cycles that influence soil fertility under pasture, which is important for devising management technologies that enhance the sustainability of these areas and thus slow further deforestation. | |||||
BibTeX:
@article{cerri_interrelationships_2006, author = {Cerri, C. E. P. and Piccolo, M. C. and Feigl, B. J. and Paustian, K. and Cerri, C. C. and Victoria, R. L. and Melillo, J. M.}, title = {Interrelationships among soil total C and N, microbial biomass, trace gas fluxes, and internal N-cycling in soils under pasture of the Amazon region}, journal = {Journal of Sustainable Agriculture}, year = {2006}, volume = {27}, number = {4}, pages = {45--69}, url = {://WOS:000238335900004}, doi = {https://doi.org/10.1300/J064v27n04_05} } |
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Cerri, C.E.P., Paustian, K., Bernoux, M., Victoria, R.L., Melillo, J.M. and Cerri, C.C. | Modeling changes in soil organic matter in Amazon forest to pasture conversion with the Century model | 2004 | Global Change Biology Vol. 10(5), pp. 815-832 |
article | DOI URL |
Abstract: Land use and land cover changes in the Brazilian Amazon region have major implications for regional and even global carbon cycling. We analyzed the effects of the predominant land use change, conversion of tropical forest to pasture, on total soil C and N, using the Century ecosystem model and data collected from the Nova Vida ranch, Western Brazilian Amazon. We estimated equilibrium organic matter levels, plant productivity and residue carbon inputs under native forest conditions, then simulated deforestation following the slash and burn procedure. Soil organic matter dynamics were simulated for pastures established in 1989, 1987, 1983, 1979, 1972, 1951, and 1911. Using input data from the Nova Vida ranch, the Century model predicted that forest clearance and conversion to pasture would cause an initial decline in soil C and N stocks, followed by a slow rise to levels exceeding those under native forest. Simulated soil total C and N levels (2500 g C m(-2) and 245 g N m(-2) in the 0-20 cm layer) prior to conversion to pasture were close to those measured in the native forest. Simulated above- and below-ground biomass for the forest and pasture were comparable with literature values from this region. The model predicted the long-term changes in soil C and N under pasture inferred from the pasture chronosequence, but there was considerable variation in soil C stocks for pastures textless20 years in age. Differences in soil texture between pastures were relatively small and could not account for much of the variability between different pastures of similar ages, in either the measured or simulated data. It is likely that much of the variability in C stocks between pastures of similar ages is related to initial C stocks immediately following deforestation and that this was the largest source of variability in the chronosequence. Internal C cycling processes in Century were evaluated using measurements of microbial biomass and soil delta(13)C. The relative magnitude and long-term trend in microbial biomass simulated by the model were consistent with measurements. The close fit of simulated to measured values of delta(13)C over time suggests that the relative loss of forest-derived C and its replacement by pasture-derived C was accurately predicted by the model. After 80 years, almost 90% of the organic matter in the top 20 cm was pasture derived. While our analysis represents a single 'case study' of pasture conversion, our results suggest that modeling studies in these pasture systems can help to evaluate the magnitude of impacts on C and N cycling, and determine the effect of management strategies on pasture sustainability. | |||||
BibTeX:
@article{cerri_modeling_2004, author = {Cerri, C. E. P. and Paustian, K. and Bernoux, M. and Victoria, R. L. and Melillo, J. M. and Cerri, C. C.}, title = {Modeling changes in soil organic matter in Amazon forest to pasture conversion with the Century model}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {815--832}, url = {://WOS:000221421600020 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2004.00759.x/asset/j.1365-2486.2004.00759.x.pdf?v=1&t=h6hyl32l&s=254f7acc32c4d49120b4ab2d6254761846268ff1}, doi = {https://doi.org/10.1111/j.1365-2486.2004.00759.x} } |
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Cerri, C.E.P., Easter, M., Paustian, K., Killian, K., Coleman, K., Bernoux, M., Falloon, P., Powlson, D.S., Batjes, N.H., Milne, E. and Cerri, C.C. | Predicted soil organic carbon stocks and changes in the Brazilian Amazon between 2000 and 2030 | 2007 | Agriculture Ecosystems & Environment Vol. 122(1), pp. 58-72 |
article | DOI URL |
Abstract: Currently we have little understanding of the impacts of land use change on soil C stocks in the Brazilian Amazon. Such information is needed to determine impacts'6n the global C cycle and the sustainability of agricultural systems that are replacing native forest. The aim of this study was to predict soil carbon stocks and changes in the Brazilian Amazon during the period between 2000 and 2030, using the GEFSOC soil carbon (C) modelling system. In order to do so, we devised current and future land use scenarios for the Brazilian Amazon, taking into account: (i) deforestation, rates from the past three decades, (ii) census data on land use from 1940 to 2000, including the expansion and intensification of agriculture in the region, (iii) available information on management practices, primarily related to well managed pasture versus degraded pasture and conventional systems versus no-tillage systems for soybean (Glycine max) and (iv) FAO predictions on agricultural land use and land use changes for the years 2015 and 2030. The land use scenarios were integrated with spatially explicit soils data (SOTER database), climate, potential natural vegetation and land management units using the recently developed GEFSOC soil C modelling system. Results are presented in map, table and graph form for the entire Brazilian Amazon for the current situation (1990 and 2000) and the future (2015 and 2030). Results include soil organic C (SOC) stocks and SOC stock change rates estimated by three methods: (i) the Century ecosystem model, (ii) the Rothamsted C model and (iii) the intergovernmental panel on climate change (IPCC) method for assessing soil C at regional scale. In addition, we show estimated values of above and belowground biomass for native vegetation, pasture and soybean. The results on regional SOC stocks compare reasonably well with those based on mapping approaches. The GEFSOC system provided a means of efficiently handling complex interactions among biotic-edapho-climatic conditions (textgreater 363,000 combinations) in a very large area (similar to 500 Mha) such as the Brazilian Amazon. All of the methods used showed a decline in SOC stock for the period studied; Century and RothC simulated values for 2030 being about 7% lower than those in 1990. Values from Century and RothC (30,430 and 25,000 Tg for the 0-20 cm layer for the Brazilian Amazon region were higher than those obtained from the IPCC system (23,400 Tg in the 0-30 cm layer). Finally; our results can help understand the major biogeochemical cycles that influence soil fertility and help devise management strategies that enhance the sustainability of these areas and thus slow further deforestation. (C) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{cerri_predicted_2007, author = {Cerri, C. E. P. and Easter, M. and Paustian, K. and Killian, K. and Coleman, K. and Bernoux, M. and Falloon, P. and Powlson, D. S. and Batjes, N. H. and Milne, E. and Cerri, C. C.}, title = {Predicted soil organic carbon stocks and changes in the Brazilian Amazon between 2000 and 2030}, journal = {Agriculture Ecosystems & Environment}, year = {2007}, volume = {122}, number = {1}, pages = {58--72}, url = {://WOS:000246320300007}, doi = {https://doi.org/10.1016/j.agee.2007.01.008} } |
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Cerri, C.E.P., Easter, M., Paustian, K., Killian, K., Coleman, K., Bernoux, M., Falloon, P., Powlson, D.S., Batjes, N., Milne, E. and Cerri, C.C. | Simulating SOC changes in 11 land use change chronosequences from the Brazilian Amazon with RothC and Century models | 2007 | Agriculture Ecosystems & Environment Vol. 122(1), pp. 46-57 |
article | DOI URL |
Abstract: Land use and land cover changes in the Brazilian Amazon have major implications for regional and global carbon (C) cycling. Cattle pasture represents the largest single use (about 70%) of this once-forested land in most of the region. The main objective of this study was to evaluate the accuracy of the RothC and Century models at estimating soil organic C (SOC) changes under forest-to-pasture conditions in the Brazilian Amazon. We used data from 11 site-specific 'forest to pasture' chronosequences with the Century Ecosystem Model (Century 4.0) and the Rothamsted C Model (RothC 26.3). The models predicted that forest clearance and conversion to well managed pasture would cause an initial decline in soil C stocks (0-20 cm depth), followed in the majority of cases by a slow rise to levels exceeding those under native forest. One exception to this pattern was a chronosequence in Suia-Missu, which is under degraded pasture. In three other chronosequences the recovery of soil C under pasture appeared to be only to about the same level as under the previous forest. Statistical tests were applied to determine levels of agreement between simulated SOC stocks and observed stocks for all the sites within the 11 chronosequences. The models also provided reasonable estimates (coefficient of correlation = 0.8) of the microbial biomass C in the 0-10 cm soil layer for three chronosequences, when compared with available measured data. The Century model adequately predicted the magnitude and the overall trend in delta C-13 for the six chronosequences where measured 813 C data were available. This study gave independent tests of model performance, as no adjustments were made to the models to generate outputs. Our results suggest that modelling techniques can be successfully used for monitoring soil C stocks and changes, allowing both the identification of current patterns in the soil and the projection of future conditions. Results were used and discussed not only to evaluate soil C dynamics but also to indicate soil C sequestration opportunities for the Brazilian Amazon region. Moreover, modelling studies in these 'forest to pasture' systems have important applications, for example, the calculation of CO, emissions from land use change in national greenhouse gas inventories. (0 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{cerri_simulating_2007, author = {Cerri, Carlos E. P. and Easter, Mark and Paustian, Keith and Killian, Kendrick and Coleman, Kevin and Bernoux, Martial and Falloon, Pete and Powlson, David S. and Batjes, Niels and Milne, Eleanor and Cerri, Carlos C.}, title = {Simulating SOC changes in 11 land use change chronosequences from the Brazilian Amazon with RothC and Century models}, journal = {Agriculture Ecosystems & Environment}, year = {2007}, volume = {122}, number = {1}, pages = {46--57}, url = {://WOS:000246320300006}, doi = {https://doi.org/10.1016/j.agee.2007.01.007} } |
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Cerri, C.E.P., Coleman, K., Jenkinson, D.S., Bernoux, M., Victoria, R. and Cerri, C.C. | Modeling soil carbon from forest and pasture ecosystems of Amazon, Brazil | 2003 | Soil Science Society of America Journal Vol. 67(6), pp. 1879-1887 |
article | URL |
Abstract: Conversion of tropical forest to agricultural management has important implications for C storage in soils and global climate change. The Nova Vida Ranch in the Western Brazilian Amazon basin provided a unique opportunity to study the conversion of tropical forests to pastures established in 1989, 1987, 1983, 1979, 1972, 1951, and 1911, in comparison with uncleared forest. Soils were analyzed for organic C, bulk density, total N, pH, clay content, and biomass C. The forest soil contained 34 Mg C ha(-1) in the 0- to 30-cm layer: modeling clearance and conversion to pasture caused an initial fall in the C stock, followed by a slow rise. After 88 yr, the pasture soil contained 53% more C than the forest soil. The increase in total N on conversion to pasture was less marked, which led to C/N ratios in the pasture soils being higher than in the forest soil. The Rothamsted C turnover model (RothC-26.3) was used to simulate changes in the 0- to 10- and 0- to 30-cm layer of soils when forest was converted to pasture. The model predicted that conversion to pasture would cause a 54% increase in the stock of organic C in the top 30 cm of soil in 100 yr. The modeled input of plant C to the 0- to 30-cm layer of soil under pasture was assumed to be 8.28 Mg C ha(-1) yr(-1). The model provided a reasonable estimate of the microbial biomass (BIO) C in the 0- to 10-cm soil layer. This was an independent test of model performance, because no adjustments were made to the model to generate output. | |||||
BibTeX:
@article{cerri_modeling_2003, author = {Cerri, C. E. P. and Coleman, K. and Jenkinson, D. S. and Bernoux, M. and Victoria, R. and Cerri, C. C.}, title = {Modeling soil carbon from forest and pasture ecosystems of Amazon, Brazil}, journal = {Soil Science Society of America Journal}, year = {2003}, volume = {67}, number = {6}, pages = {1879--1887}, url = {://WOS:000186450500029} } |
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Cerri, C., Cerri, C., Paustian, K., Bernoux, M. and Mellilo, J. | Combining soil C and N spatial variability and modeling approaches for measuring and monitoring soil carbon sequestration | 2004 | Environmental Management Vol. 33, pp. S274-S288 |
article | DOI URL |
Abstract: The main objective of the study was to investigate soil carbon and nitrogen stocks in five soil types within a 63-ha Amazon degraded pasture area using the Century model and to combine this information with soil C and N spatial variability at Nova Vida ranch in the western Brazilian Amazon. Samples for soil chemical, physical, and biological analyses were collected at eight different georreferenced points in each of five studied soil types. Century was used to simulate soil C and N contents in the 0-to 20-cm layer in each soil type within a 63-ha degraded pasture area. Century accurately simulated the level of total soil C and N for the five soil types, but it was not successful in predicting seasonal variations in microbial biomass C. The influence of soil texture and hydrological process affecting the ability of soils to accumulate soil organic matter were discussed. Scenarios for soil C and N stocks with varying pasture management were examined through a period of 40 years after deforestation. In conclusion, modeling and geostatistical techniques can be used for measuring and monitoring soil C and N stocks. Modeling provides a flexible and powerful way to assess how different scenarios for pasture management and land use change can affect soil C and N dynamics, but it is important to highlight that even the best models (as Century is) need to be used with caution for Kyoto Protocol projects at plot scale and that benchmark sites are needed to augment model predictions. | |||||
BibTeX:
@article{cerri_combining_2004, author = {Cerri, C.E.P. and Cerri, C.C. and Paustian, K. and Bernoux, M. and Mellilo, J.M.}, title = {Combining soil C and N spatial variability and modeling approaches for measuring and monitoring soil carbon sequestration}, journal = {Environmental Management}, year = {2004}, volume = {33}, pages = {S274--S288}, url = {://WOS:000203094700025 http://www.springerlink.com/content/p78a1404bd1ybd99/fulltext.pdf}, doi = {https://doi.org/10.1007/s00267-003-9137-y} } |
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Cerri, C.E.P., Bernoux, M., Chaplot, V., Volkoff, B., Victoria, R.L., Melillo, J.M., Paustian, K. and Cerri, C.C. | Assessment of soil property spatial variation in an Amazon pasture: basis for selecting an agronomic experimental area | 2004 | Geoderma Vol. 123(1-2), pp. 51-68 |
article | DOI URL |
Abstract: Our main objective in the present study was to assess the spatial variation of chemical and physical soil properties and then use this information to select an appropriate area to install a pasture rehabilitation experiment in the Amazon region, Brazil. A regular 25 m grid was used for collecting a total of 2955 soil samples (from 985 georeferenced soil pits) at 0 to 10, 10 to 20 and 20 to 30 cm layers. Soil samples were analyzed for total carbon and nitrogen, delta(13)C and delta(15)N, pH in H2O, pH in KCl, clay, and sand contents. Conventional statistical methods and geostatistics were performed in order to analyze soil properties spatial dependence. Mean, standard deviation, skewness, and kurtosis for all measured variables were evaluated. All variograms generally were well structured with a relatively large nugget effect. Total C, total N, pH in H2O, pH in KCl, delta(13)C and delta(15)N semivariograms were best fitted by spherical models, while clay and sand contents were best fitted by exponential models. Two types of validation ("Jackknife" or cross-validation and external validation) were conducted, indicating a lack of bias for the used prediction models. Block kriging was used to interpolate the values at unmeasured locations, generating maps of spatial variation for each soil property. Those maps were processed using Geographic Information System and restrictive criteria were adopted in order to select the best area in which to install the pasture rehabilitation experiment. The study field was then divided into zones with similar homogeneity. The selected zone can now be subjected to different treatments once the natural initial conditions are well known, and could also be used as a baseline in carbon sequestration projects within the scope of the Kyoto Protocol's Clean Development Mechanism. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{cerri_assessment_2004, author = {Cerri, C. E. P. and Bernoux, M. and Chaplot, V. and Volkoff, B. and Victoria, R. L. and Melillo, J. M. and Paustian, K. and Cerri, C. C.}, title = {Assessment of soil property spatial variation in an Amazon pasture: basis for selecting an agronomic experimental area}, journal = {Geoderma}, year = {2004}, volume = {123}, number = {1-2}, pages = {51--68}, url = {://WOS:000224881800004}, doi = {https://doi.org/10.1016/j.geoderma.2004.01.027} } |
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Cerri, C.C., Melillo, J.M., Feigl, B.J., Piccolo, M.C., Neill, C., Steudler, P.A., Carvalho, M.D.S., Godinho, V.P., Eduardo, C., Cerri, P. and Bernoux, M. | Recent history of the agriculture of the Brazilian Amazon Basin - Prospects for sustainable development and a first look at the biogeochemical consequences of pasture reformation | 2005 | Outlook on Agriculture Vol. 34(4), pp. 215-223 |
article | URL |
Abstract: Land-use change for human settlement and agricultural purposes, especially pasture establishment, has caused major impacts on the Amazon Basin's environment. Development of strategies for reformation and restoration of already degraded pastures constitutes the main goal of the authors' research work. For some of this work, a homogeneous area of land in terms of soil characteristics was selected at Nova Vida ranch in Rondonia state to conduct a multidisciplinary experiment, which included agronomic, environmental and economic analyses. Since July 2001, the authors have monitored five treatments: control, herbicide, tillage, no-till rice and no-till soybean, arranged in four blocks. Early results on carbon and nitrogen stocks, nitrogen mineralization, trace-gas fluxes, dissolved organic carbon and microbial biomass are briefly presented. | |||||
BibTeX:
@article{cerri_recent_2005, author = {Cerri, C. C. and Melillo, J. M. and Feigl, B. J. and Piccolo, M. C. and Neill, C. and Steudler, P. A. and Carvalho, M. D. S. and Godinho, V. P. and Eduardo, C. and Cerri, P. and Bernoux, M.}, title = {Recent history of the agriculture of the Brazilian Amazon Basin - Prospects for sustainable development and a first look at the biogeochemical consequences of pasture reformation}, journal = {Outlook on Agriculture}, year = {2005}, volume = {34}, number = {4}, pages = {215--223}, url = {://WOS:000234972400002} } |
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Cerri, C.C., Bernoux, M., Cerri, C.E.P. and Feller, C. | Carbon cycling anal sequestration opportunities in South America: the case of Brazil | 2004 | Soil Use and Management Vol. 20, pp. 248-254 |
article | DOI URL |
Abstract: A carbon emission inventory of the Brazilian agricultural sector was used to compare greenhouse gas emissions with estimated carbon offsets promoted by two main changes in agricultural management: the replacement of conventional tillage by no-tillage and the cessation of annual burning in sugar cane production. Using the IPCC revised 1996 guidelines for national greenhouse gas inventories, we estimate that 12.65 Mt C are emitted annually from agricultural land in Brazil. Ongoing conversion of conventionally tilled land to no-tillage currently accumulates 9 Mt C yr(-1). Industrial by-products like alcohol and bagasse from sugar cane processing substitute fossil fuel for transportation and power generation offsetting 10 and 8 Mt C yr(-1), respectively. An additional opportunity for 0.53 Mt C yr(-1) sequestration is presented by avoiding burning before harvesting of sugar cane. These data show that there could be almost full compensation between sources and sinks/offsets in the agricultural carbon cycle. There is a great opportunity to achieve this mitigation benefit because the adoption of new technologies is increasing rapidly. | |||||
BibTeX:
@article{cerri_carbon_2004, author = {Cerri, C. C. and Bernoux, M. and Cerri, C. E. P. and Feller, C.}, title = {Carbon cycling anal sequestration opportunities in South America: the case of Brazil}, journal = {Soil Use and Management}, year = {2004}, volume = {20}, pages = {248--254}, url = {://WOS:000224094100006}, doi = {https://doi.org/10.1079/sum2004237} } |
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Cecchini, M.A., Machado, L.A.T., Comstock, J.M., Mei, F., Wang, J., Fan, J., Tomlinson, J.M., Schmid, B., Albrecht, R., Martin, S.T. and Artaxo, P. | Impacts of the Manaus pollution plume on the microphysical properties of Amazonian warm-phase clouds in the wet season [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 7029-7041 |
article | DOI |
BibTeX:
@article{cecchini_impacts_2016, author = {Cecchini, Micael A. and Machado, Luiz A. T and Comstock, Jennifer M. and Mei, Fan and Wang, Jian and Fan, Jiwen and Tomlinson, Jason M. and Schmid, Beat and Albrecht, Rachel and Martin, Scot T. and Artaxo, Paulo}, title = {Impacts of the Manaus pollution plume on the microphysical properties of Amazonian warm-phase clouds in the wet season}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {7029--7041}, doi = {https://doi.org/10.5194/acp-2015-1049} } |
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Cecchini, M.A., Machado, L.A.T., Andreae, M.O., Martin, S.T., Albrecht, R.I., Artaxo, P., Barbosa, H.M.J., Borrmann, S., Fütterer, D., Jurkat, T., Mahnke, C., Minikin, A., Molleker, S., Pöhlker, M.L., Pöschl, U., Rosenfeld, D., Voigt, C., Wenzierl, B. and Wendisch, M. | Sensitivities of Amazonian clouds to aerosols and updraft speed [BibTeX] |
2017 | Atmos. Chem. Phys. Vol. 17, pp. 10037-10050 |
article | DOI |
BibTeX:
@article{cecchini_sensitivities_2017, author = {Cecchini, M. A. and Machado, L. A. T. and Andreae, M. O. and Martin, S. T. and Albrecht, R. I. and Artaxo, P. and Barbosa, H. M. J. and Borrmann, S. and Fütterer, D. and Jurkat, T. and Mahnke, C. and Minikin, A. and Molleker, S. and Pöhlker, M. L. and Pöschl, U. and Rosenfeld, D. and Voigt, C. and Wenzierl, B. and Wendisch, M.}, title = {Sensitivities of Amazonian clouds to aerosols and updraft speed}, journal = {Atmos. Chem. Phys.}, year = {2017}, volume = {17}, pages = {10037--10050}, doi = {https://doi.org/10.5194/acp-2017-89} } |
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Cecchini, M.A., de Bruine, M., Vilà-Guerau de Arellano, J. and Artaxo, P. | Quantifying vertical wind shear effects in shallow cumulus clouds over Amazonia [BibTeX] |
2022 | Atmos. Chem. Phys. Discuss. Vol. 2022, pp. 1-33 |
article | DOI URL |
BibTeX:
@article{cecchini_quantifying_2022, author = {Cecchini, M. A. and de Bruine, M. and Vilà-Guerau de Arellano, J. and Artaxo, P.}, title = {Quantifying vertical wind shear effects in shallow cumulus clouds over Amazonia}, journal = {Atmos. Chem. Phys. Discuss.}, year = {2022}, volume = {2022}, pages = {1--33}, url = {https://acp.copernicus.org/preprints/acp-2021-1060/}, doi = {https://doi.org/10.5194/acp-2021-1060} } |
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Cavalcanti, I.F.A., Marengo, J.A., Satyamurty, P., Nobre, C.A., Trosnikov, I., Bonatti, J.P., Manzi, A.O., Tarasova, T., Pezzi, L.P., D'Almeida, C., Sampaio, G., Castro, C.C., Sanches, M.B. and Camargo, L. | Global climatological features in a simulation using the CPTEC-COLA AGCM | 2002 | Journal of Climate Vol. 15(21), pp. 2965-2988 |
article | DOI URL |
Abstract: The Center for Weather Forecasting and Climate Studies-Center for Ocean-Land-Atmosphere Studies (CPTEC-COLA) atmospheric general circulation model (AGCM) is integrated with nine initial conditions for 10 yr to obtain the model climate in an ensemble mode. The global climatological characteristics simulated by the model are compared with observational data, and emphasis is given to the Southern Hemisphere and South America. Evaluation of the model's performance is presented by showing systematic errors of several variables, and anomaly correlation and reproducibility are applied to precipitation. The model is able to simulate the main features of the global climate, and the results are consistent with analyses of other AGCMs. The seasonal cycle is reproduced well in all analyzed variables, and systematic errors occur at the same regions in different seasons. The Southern Hemisphere convergence zones are simulated reasonably well, although the model overestimates precipitation in the southern portions and underestimates it in the northern portions of these systems. The high- and low-level main circulation features such as the subtropical highs, subtropical jet streams, and storm tracks are depicted well by the model, albeit with different intensities from the reanalysis. The stationary waves of the Northern and Southern Hemispheres are weaker in the model; however, the dominant wavenumbers are similar to the observations. The energy budget analysis shows values of some radiative fluxes that are close to observations, but the unbalanced fluxes in the atmosphere and at the surface indicate that the radiation and cloud scheme parameterizations need to be improved. Besides these improvements, changes in the convection scheme and higher horizontal resolution to represent orographic effects better are being planned to improve the model's performance. | |||||
BibTeX:
@article{cavalcanti_global_2002, author = {Cavalcanti, I. F. A. and Marengo, J. A. and Satyamurty, P. and Nobre, C. A. and Trosnikov, I. and Bonatti, J. P. and Manzi, A. O. and Tarasova, T. and Pezzi, L. P. and D'Almeida, C. and Sampaio, G. and Castro, C. C. and Sanches, M. B. and Camargo, L.}, title = {Global climatological features in a simulation using the CPTEC-COLA AGCM}, journal = {Journal of Climate}, year = {2002}, volume = {15}, number = {21}, pages = {2965--2988}, url = {://WOS:000178601100001 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282002%29015%3C2965%3AGCFIAS%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0442(2002)015%3C2965:gcfias%3E2.0.co;2} } |
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Cava, D., Dias-Júnior, C.Q., Acevedo, O., Oliveira, P.E.S., Tsokankunku, A., Sörgel, M., Manzi, A.O., de Araújo, A.C., Brondani, D.V., Toro, I.M.C. and Mortarini, L. | Vertical propagation of submeso and coherent structure in a tall and dense Amazon Forest in different stability conditions PART I: Flow structure within and above the roughness sublayer | 2022 | Agricultural and Forest Meteorology Vol. 322, pp. 108983 |
article | DOI URL |
Abstract: Understanding the processes that govern the mixing and transport of scalars within and above the Amazon Forest is of great importance for many environmental applications. The impact of atmospheric stability on the roughness sublayer (RSL) as well as the influence on it by the processes in the overlying atmosphere are investigated using measurements collected at the Atmospheric Tall Tower Observatory. Five different stabilities are defined according to the turbulent fluxes’ behaviour. Ejections dominate the transport in the RSL. In near neutral and unstable conditions coherent structures propagate up to 2–3 times the canopy height (h) and intermittently penetrate in the lowest part of the forest where sweeps drive the transport processes. In the unstable regime a weakening of the wind inflection at the canopy top and a transition to a convective regime above z = 2 h are observed. In stable conditions three regimes were defined characterised by a progressive lowering of the RSL and the weakening of the mixing-layer type coherent structures. In the ‘weakly stable’ regime the intense momentum and scalar fluxes appear driven by the coherent structures being able to penetrate inside the canopy intermittently coupling the flow above and within the forest. The ‘very stable’ regime is characterized by weak winds, a weakening of coherent structures and a decrease of the turbulent fluxes inhibited by buoyancy. The definition of a ‘super stable’ regime allowed the identification of a peculiar condition characterized by low-wind and weak coherent structures confined close to the canopy top and producing negligible transport. Submeso motions dominate the flow dynamics in this regime both above and inside the RSL. Multiresolution analysis highlights the ability of submeso motions to propagate inside the canopy and to modulate the exchange, particularly of scalars, fully driving the large positive CO2 flux observed inside the forest in the super stable regime. | |||||
BibTeX:
@article{cava_vertical_2022, author = {Cava, Daniela and Dias-Júnior, Cléo Q. and Acevedo, Otávio and Oliveira, Pablo E. S. and Tsokankunku, Anywhere and Sörgel, Matthias and Manzi, Antônio Ocimar and de Araújo, Alessandro C. and Brondani, Daiane V. and Toro, Ivan Mauricio Cely and Mortarini, Luca}, title = {Vertical propagation of submeso and coherent structure in a tall and dense Amazon Forest in different stability conditions PART I: Flow structure within and above the roughness sublayer}, journal = {Agricultural and Forest Meteorology}, year = {2022}, volume = {322}, pages = {108983}, url = {https://www.sciencedirect.com/science/article/pii/S0168192322001733}, doi = {https://doi.org/10.1016/j.agrformet.2022.108983} } |
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Cattanio, J.H., Kuehne, R. and Vlek, P.L.G. | Organic material decomposition and nutrient dynamics in a mulch system enriched with leguminous trees in the Amazon | 2008 | Revista Brasileira De Ciencia Do Solo Vol. 32(3), pp. 1073-1086 |
article | URL |
Abstract: The new techniques proposed for agriculture in the Amazon region include rotational fallow systems enriched with leguminous trees and the replacement of biomass burning by mulching. Decomposition and nutrient release from mulch were studied using fine-mesh litterbags with five different leguminous species and the natural fallow vegetation as control. Samples from each treatment were analyzed for total C, N, P, K, Ca, Mg, lignin, cellulose content and soluble polyphenol at different sampling times over the course of one year. The decomposition rate constant varied with species and time. Weight loss from the decomposed litter bag material after 96 days was 30.1 % for Acacia angustissima, 32.7 % for Sclerolobium paniculatum, 33.9 % for Iinga edulis and the Fallow vegetation, 45.2 % for Acacia mangium and 63.6 % for Clitoria racemosa. Immobilization of N and P was observed in all studied treatments. Nitrogen mineralization was negatively correlated with phenol, C-to-N ratio, lignin + phenol/N ratio, and phenol/phosphorus ratios and with N content in the litterbag material. After 362 days of field incubation, an average (of all treatments), 3.3 % K, 32.2 % Ca and 22.4 % Mg remained in the mulch. Results confirm that low quality and high amount of organic C as mulch application are limiting for the quantity of energy available for microorganisms and increase the nutrient immobilization for biomass decomposition, which results in competition for nutrients with the crop plants. | |||||
BibTeX:
@article{cattanio_organic_2008, author = {Cattanio, Jose Henrique and Kuehne, Ronald and Vlek, Paul L. G.}, title = {Organic material decomposition and nutrient dynamics in a mulch system enriched with leguminous trees in the Amazon}, journal = {Revista Brasileira De Ciencia Do Solo}, year = {2008}, volume = {32}, number = {3}, pages = {1073--1086}, url = {://WOS:000258415500016} } |
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Cattanio, J.H., Davidson, E.A., Nepstad, D.C., Verchot, L.V. and Ackerman, I.L. | Unexpected results of a pilot throughfall exclusion experiment on soil emissions of CO(2), CH(4), N(2)O, and NO in eastern Amazonia | 2002 | Biology and Fertility of Soils Vol. 36(2), pp. 102-108 |
article | DOI URL |
Abstract: The eastern Amazon Basin may become drier as a result of less regional recirculation of water in a largely deforested landscape and because of increased frequency and intensity of El Nino events induced by global warming. Drier conditions may affect several plant and soil microbial processes, including soil emissions of CO(2), CH(4), NO, and N(2)O. We report here unanticipated results of a pilot study that was initiated to test the feasibility of a larger-scale throughfall exclusion experiment. In particular, soil drying caused a switch from net consumption of atmospheric CH(4) by soils in the control plot to net CH(4) emission from soils in the experimentally dried plot. This result is surprising because production of CH(4) requires anaerobic microsites, which are uncommon in dry soil. A plausible explanation for increased CH(4) emissions in the dried plot is that dry soil conditions favor termite activity and increased coarse root mortality provides them with a substrate. Another surprise was,that both NO and N(2)O fluxes were elevated several years after initiation of the drying experiment. Apparently, a pulse of N availability caused by experimental drying persisted for at least 3 years. As expected, CO(2) emissions were lower in the dried plots, which is consistent with lower rates of root growth observed in root in-growth cores placed in the dried plots. More work is needed to test these explanations and to confirm these phenomena, but these results demonstrate that changes in climate could have unanticipated effects on biogeochemical processes in soils that we do not adequately understand. | |||||
BibTeX:
@article{cattanio_unexpected_2002, author = {Cattanio, J. H. and Davidson, E. A. and Nepstad, D. C. and Verchot, L. V. and Ackerman, I. L.}, title = {Unexpected results of a pilot throughfall exclusion experiment on soil emissions of CO(2), CH(4), N(2)O, and NO in eastern Amazonia}, journal = {Biology and Fertility of Soils}, year = {2002}, volume = {36}, number = {2}, pages = {102--108}, url = {://WOS:000178275500003 http://www.springerlink.com/content/0pd0lgmuc0c9t8xy/fulltext.pdf}, doi = {https://doi.org/10.1007/s00374-002-0517-x} } |
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Castro, R.M.S., Ruivo, M.L.P., Santos, S.F. and Rodrigues, P.G. | Influência do estresse hídrico sobre a decomposição da serapilheira em floresta amazônica de terra firme [BibTeX] |
2017 | Boletim do Museu Paraense Emílio Goeldi. Ciências Naturais Vol. 11(3), pp. 343-350 |
article | |
BibTeX:
@article{castro_influencia_2017, author = {Castro, R. M. S. and Ruivo, M. L. P. and Santos, S. F. and Rodrigues, P. G.}, title = {Influência do estresse hídrico sobre a decomposição da serapilheira em floresta amazônica de terra firme}, journal = {Boletim do Museu Paraense Emílio Goeldi. Ciências Naturais}, year = {2017}, volume = {11}, number = {3}, pages = {343--350} } |
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Castro, E.R.d. | Sociedade, Território e Conflitos: BR-163 em questão [BibTeX] |
2008 | Vol. 1 |
book | |
BibTeX:
@book{castro_sociedade_2008, author = {Castro, Edna Ramos de}, title = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, note = {Section: 297p.} } |
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Castilho, C.V.d., Magnusson, W.E., de Araujo, R.N.O. and Luizao, F.J. | Short-Term Temporal Changes in Tree Live Biomass in a Central Amazonian Forest, Brazil | 2010 | Biotropica Vol. 42(1), pp. 95-103 |
article | DOI URL |
Abstract: We monitored seventy-two 1 ha permanent plots spread over 64 km 2 of terra firme forest at Reserva Ducke (Manaus, Amazonas, Brazil) over 2-yr intervals to assess the effects of a soil and topographic gradient on the rate of change in the aboveground tree live biomass (AGLB). AGLB increased significantly over the 2-yr intervals, exhibiting a mean rate of change of 1.65 Mg/ha/yr (bootstrapped 95% CI: 1.15, 2.79). The rate of change varied according to tree size class; understory and sub-canopy trees exhibited higher rates of change. Over the whole period, the rate of change was not related to soil or topographic features of the plots, but there was evidence that the relationships varied depending on the year of measurement. In the plots monitored between 2001 and 2003 we found a significant relationship between AGLB change and the soil textural gradient, but this relationship was not evident in plots monitored between 2002 and 2004. This suggests that both the temporal variation in the soil-biomass change relationship and the size structure of the forest need to be included in models of biomass change in Amazonia. We also noted that the rate of biomass change is sensitive to the equation used to estimate AGLB. Allometric models that incorporate wood-density data provide higher per plot AGLB estimates, but lower rates of change, suggesting that variations in floristic composition have important implications for carbon cycling in diverse tropical forests. | |||||
BibTeX:
@article{castilho_short-term_2010, author = {Castilho, Carolina V. de and Magnusson, William E. and de Araujo, R. Nazare O. and Luizao, Flavio J.}, title = {Short-Term Temporal Changes in Tree Live Biomass in a Central Amazonian Forest, Brazil}, journal = {Biotropica}, year = {2010}, volume = {42}, number = {1}, pages = {95--103}, url = {://WOS:000273301100014 http://onlinelibrary.wiley.com/store/10.1111/j.1744-7429.2009.00543.x/asset/j.1744-7429.2009.00543.x.pdf?v=1&t=h6hyiqfv&s=6c00dc153733c6145a159f4123e23a7154fc81ea}, doi = {https://doi.org/10.1111/j.1744-7429.2009.00543.x} } |
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Castanho, A.D.d.A., Martins, J.V. and Artaxo, P. | MODIS aerosol optical depth Retrievals with high spatial resolution over an urban area using the critical reflectance | 2008 | Journal of Geophysical Research-Atmospheres Vol. 113(D2) |
article | DOI URL |
Abstract: [1] The retrieval of aerosol optical depth (Ta) over land by satellite remote sensing is still a challenge when a high spatial resolution is required. This study presents a tool that uses satellite measurements to dynamically identify the aerosol optical model that best represents the optical properties of the aerosol present in the atmosphere. We use aerosol critical reflectance to identify the single scattering albedo of the aerosol layer. Two case studies show that the Sao Paulo region can have different aerosol properties and demonstrates how the dynamic methodology works to identify those differences to obtain a better T a retrieval. The methodology assigned the high single scattering albedo aerosol model (pi o( lambda = 0.55) = 0.90) to the case where the aerosol source was dominated by biomass burning and the lower pi(o) model (pi(o) (lambda = 0.55) = 0.85) to the case where the local urban aerosol had the dominant influence on the region, as expected. The dynamic methodology was applied using cloud-free data from 2002 to 2005 in order to retrieve Ta with Moderate Resolution Imaging Spectroradiometer ( MODIS). These results were compared with collocated data measured by AERONET in Sao Paulo. The comparison shows better results when the dynamic methodology using two aerosol optical models is applied (slope 1.06 +/- 0.08 offset 0.01 +/- 0.02 r(2) 0.6) than when a single and fixed aerosol model is used (slope 1.48 +/- 0.11 and offset - 0.03 +/- 0.03 r(2) 0.6). In conclusion the dynamical methodology is shown to work well with two aerosol models. Further studies are necessary to evaluate the methodology in other regions and under different conditions. | |||||
BibTeX:
@article{castanho_modis_2008, author = {Castanho, Andrea D. de Almeida and Martins, J. Vanderlei and Artaxo, Paulo}, title = {MODIS aerosol optical depth Retrievals with high spatial resolution over an urban area using the critical reflectance}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2008}, volume = {113}, number = {D2}, url = {://WOS:000252568400003 http://www.agu.org/journals/jd/jd0802/2007JD008751/2007JD008751.pdf}, doi = {https://doi.org/10.1029/2007jd008751} } |
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Castanho, M.T., Costa, M.H., Malhi, Y., Galbraith, D., Quesada C. A., A.D.A. and Coe | Improving simulated Amazon forest biomass and productivity by including spatial variation in biophysical parameters [BibTeX] |
2013 | Biogeosciences Vol. 10, pp. 2255-2272 |
article | |
BibTeX:
@article{castanho_improving_2013, author = {Castanho, M. T. ; Costa, M. H. ; Malhi, Y. ; Galbraith, D. ; Quesada, C. A., A. D. A. ; Coe}, title = {Improving simulated Amazon forest biomass and productivity by including spatial variation in biophysical parameters}, journal = {Biogeosciences}, year = {2013}, volume = {10}, pages = {2255--2272} } |
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Carvalho, L. and Silva-Dias, M. | Sensibilidade das dimensões fractais de contagem de caixa às imagens de satélite com diferentes resoluções espaciais. [BibTeX] |
2000 | Revista Brasileira de Meteorologia Vol. 15, pp. 89-101 |
article | |
BibTeX:
@article{carvalho_sensibilidade_2000, author = {Carvalho, L.M.V. and Silva-Dias, M.A.F.}, title = {Sensibilidade das dimensões fractais de contagem de caixa às imagens de satélite com diferentes resoluções espaciais.}, journal = {Revista Brasileira de Meteorologia}, year = {2000}, volume = {15}, pages = {89--101} } |
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Carvalho, L.M.V., Jones, C. and Dias, M. | Intraseasonal large-scale circulations and mesoscale convective activity in tropical South America during the TRMM-LBA campaign | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: An investigation linking the large-scale intraseasonal variability in low-level wind regimes and mesoscale convective activity in tropical South America (TSA) is presented. Observational evidence is gathered to support the hypothesis that periods of active and break phases in the South American Monsoon System (SAMS) are directly related to persistent westerly and easterly intraseasonal low-level wind-regime anomalies (10-70 days). The large-scale circulation and tropical convection features are examined in this study with 19 austral summer seasons. The pattern of significant anomalies of the low-level wind (850 hPa) and outgoing long-wave radiation (10-70 days) evidenced the existence of an enhancement/suppression dipole of large-scale features of convective activity over the northwest and southeast of TSA. Regional impacts upon the mesoscale activity during the Tropical Rainfall Measuring Mission (TRMM)/Large-Scale Biosphere Atmosphere (LBA) Experiment campaign (23 January to 28 February 1999) are investigated. The mesoscale convective activity is described with the observation of the spatial and temporal characteristics of evolving convective systems in the infrared Geostationary Operational Environmental Satellite (GOES) images. The results indicated that the northwest TSA region was subjected to the most significant contrasts in the characteristics of convective systems as the wind regime changed. During easterly regimes (or break periods), the enhancement of convective systems in the northwest TSA and decrease in the southeast TSA resembled the autumn season. Properties such as number of convective systems, diurnal distribution, radius, fraction of cold tops, and fragmentation were modulated by wind anomalies in the southeast TSA as well. | |||||
BibTeX:
@article{carvalho_intraseasonal_2002, author = {Carvalho, L. M. V. and Jones, C. and Dias, Mafs}, title = {Intraseasonal large-scale circulations and mesoscale convective activity in tropical South America during the TRMM-LBA campaign}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180367300001 http://www.agu.org/journals/jd/jd0216/2001JD000745/2001JD000745.pdf}, doi = {https://doi.org/10.1029/2001jd000745} } |
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Carvalho, J.L.N., Cerri, C.E.P., Feigl, B.J., Piccolo, M.C., Godinho, V.P. and Cerri, C.C. | Carbon sequestration in agricultural soils in the Cerrado region of the Brazilian Amazon | 2009 | Soil & Tillage Research Vol. 103(2), pp. 342-349 |
article | DOI URL |
Abstract: The introduction of crop management practices after conversion of Amazon Cerrado into cropland influences soil C stocks and has direct and indirect consequences on greenhouse gases (GHG) emissions. The aim of this study was to quantify soil C sequestration, through the evaluation of the changes in C stocks, as well as the GHG fluxes (N(2)O and CH(4)) during the process of conversion of Cerrado into agricultural land in the southwestern Amazon region, comparing no-tillage (NT) and conventional tillage (CT) systems. We collected samples from soils and made gas flux measurements in July 2004 (the dry season) and in January 2005 (the wet season) at six areas: Cerrado, CT cultivated with rice for 1 year (1CT) and 2 years (2CT), and NT cultivated with soybean for 1 year (1NT), 2 years (2NT) and 3 years (3NT), in each case after a 2-year period of rice under CT. Soil samples were analyzed in both seasons for total organic C and bulk density. The soil C stocks, corrected for a mass of soil equivalent to the 0-30-cm layer under Cerrado, indicated that soils under NT had generally higher C storage compared to native Cerrado and CT soils. The annual C accumulation rate in the conversion of rice under CT into soybean under NT was 0.38 Mg ha(-1) year(-1). Although CO(2) emissions were not used in the C sequestration estimates to avoid double counting, we did include the fluxes of this gas in our discussion. In the wet season, CO(2) emissions were twice as high as in the dry season and the highest N(2)O emissions occurred under the NT system. There were no CH(4) emissions to the atmosphere (negative fluxes) and there were no significant seasonal variations. When N(2)O and CH(4) emissions in C-equivalent were subtracted (assuming that the measurements made on 4 days were representative of the whole year), the soil C sequestration rate of the conversion of rice under CT into soybean under NT was 0.23 Mg ha(-1) year(-1). Although there were positive soil C sequestration rates, our results do not present data regarding the full C balance in soil management changes in the Amazon Cerrado. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{carvalho_carbon_2009, author = {Carvalho, J. L. N. and Cerri, C. E. P. and Feigl, B. J. and Piccolo, M. C. and Godinho, V. P. and Cerri, C. C.}, title = {Carbon sequestration in agricultural soils in the Cerrado region of the Brazilian Amazon}, journal = {Soil & Tillage Research}, year = {2009}, volume = {103}, number = {2}, pages = {342--349}, url = {://WOS:000265729900018}, doi = {https://doi.org/10.1016/j.still.2008.10.022} } |
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Carvalho, J.L.N., Cerri, C.E.P., Cerri, C.C., Feigl, B.J., Piccolo, M.C., Godinho, V.P. and Herpin, U. | Changes of chemical properties in an oxisol after clearing of native Cerrado vegetation for agricultural use in Vilhena, Rondonia State, Brazil | 2007 | Soil & Tillage Research Vol. 96(1-2), pp. 95-102 |
article | DOI URL |
Abstract: Native vegetation clearing in the Amazon Cerrado region for agricultural purposes may be modifying soil chemical characteristics. The extent of change depends on the management practices used. We evaluated changes in chemical properties of a clayey oxisol (dystrophic red yellow latosol) under no-tillage (NT) and conventional tillage (CT). Soil samples were taken randomly (n = 5) in July 2004 at 0-5 cm, 5-10 cm, 10-20 cm and 20-30 cm depths at six treatments: Cerrado with native vegetation, CT cultivated with rice for I year (1CT) and 2 years (2CT), and NT cultivated with soybean for I year (1NT), 2 years (2NT) and 3 years (3NT) in each case after a 2-year period of rice under CT. Soil pH (CaCl2, KCl and water), Delta pH, total acidity (H+ + Al3+), total organic carbon (TOC), available P, exchangeable K, Ca, Mg, potential cation exchange capacity (CEC) and base saturation (V) were determined. The highest pH values were determined in topsoil layers at the older NT adoption. Under Cerrado pH was lower than under cultivation at all depths due to absence of lime application. Generally, negative values of Delta pH were observed at all sites in all layers indicating predominant presence of negative charges in the soil. Although not statistically significant it seems that the amount of negative charges was higher in deeper layers. Total acidity displayed the highest values throughout the soil profile under Cerrado and low pH and low concentrations of exchangeable bases. Cultivated systems with fertilizer generated considerable increases of P, K, Ca, and Mg compared to Cerrado. Soil macronutrient content and base saturation under NT gradually increased throughout the profile with time. Highest CEC values were calculated for the 0-5 cm and 5-10 cm layers under Cerrado and NT systems. For the 0-5 cm layer CEC was lower at the CT system compared to the Cerrado and the oldest year under NT system. Alteration of TOC was more pronounced in the top 10 cm layer at all sites. The highest content was measured in the topsoil layer under Cerrado. Considering the future land use in Cerrado areas the NT system, if properly managed, appears to be the favourable management option of the existing croplands established after Cerrado clearing. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{carvalho_changes_2007, author = {Carvalho, J. L. N. and Cerri, C. E. P. and Cerri, C. C. and Feigl, B. J. and Piccolo, M. C. and Godinho, V. P. and Herpin, U.}, title = {Changes of chemical properties in an oxisol after clearing of native Cerrado vegetation for agricultural use in Vilhena, Rondonia State, Brazil}, journal = {Soil & Tillage Research}, year = {2007}, volume = {96}, number = {1-2}, pages = {95--102}, url = {://WOS:000250689400010}, doi = {https://doi.org/10.1016/j.still.2007.04.001} } |
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Carvalho Jr., J.A., Gurgel Veras, C.A., Alvarado, E.C., Sandberg, D.V., Leite, S.J., Gielow, R., Rabelo, E.R.C. and Santos, J.C. | Understorey fire propagation and tree mortality on adjacent areas to an Amazonian deforestation fire | 2010 | International Journal of Wildland Fire Vol. 19(6), pp. 795-799 |
article | DOI URL |
Abstract: Fire characteristics in tropical ecosystems are poorly documented quantitatively in the literature. This paper describes an understorey fire propagating across the edges of a biomass burn of a cleared primary forest. The experiment was carried out in 2001 in the Amazon forest near Alta Floresta, state of Mato Grosso, Brazil, as part of biomass burning experiments conducted in the same area since 1997. The vegetation of a 200 x 200-m(2) forested area was clear-cut in early June and burned in late August. The understorey fire that escaped from the main burn was monitored across the four sides of the land clearing area. Flame-front spread varied between 0.14 and 0.35 m min(-1). Maximum flame height was about 30 cm and typical flame depth was 10 to 15 cm. Tree mortality was investigated in 2003 in four areas adjacent to the biomass burning experiment. A total of 210 trees were counted in the four areas, 29.5% were dead as a consequence of the understorey fire that had occurred 2 years before. This fire-caused mortality is evidence of the synergistic effect between slash burning, tree mortality and future fire vulnerability on the forest-land clearing interfaces. | |||||
BibTeX:
@article{carvalho_understorey_2010, author = {Carvalho, Jr., J. A. and Gurgel Veras, C. A. and Alvarado, E. C. and Sandberg, D. V. and Leite, S. J. and Gielow, R. and Rabelo, E. R. C. and Santos, J. C.}, title = {Understorey fire propagation and tree mortality on adjacent areas to an Amazonian deforestation fire}, journal = {International Journal of Wildland Fire}, year = {2010}, volume = {19}, number = {6}, pages = {795--799}, url = {://WOS:000286181800012 http://www.publish.csiro.au/?paper=WF08047}, doi = {https://doi.org/10.1071/wf08047} } |
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Carvalho, J.A., Costa, F.S., Veras, C.A.G., Sandberg, D.V., Alvarado, E.C., Gielow, R., Serra, A.M. and Santos, J.C. | Biomass fire consumption and carbon release rates of rainforest-clearing experiments conducted in northern Mato Grosso, Brazil | 2001 | Journal of Geophysical Research-Atmospheres Vol. 106(D16), pp. 17877-17887 |
article | DOI URL |
Abstract: Biomass consumption and carbon release rates during the process of forest clearing by fire in five test plots are presented and discussed. The experiments were conducted at the Caiabi Farm, near the town of Alta Floresta, state of Mato Grosso, Brazil, in five square plots of 1 ha each, designated A, B, C, D, and E, with different locations and timing of fire. Plot A was located in the interface with a pasture, with three edges bordering on the forest, and was cut and burned in 1997. Plots B,C, D, and E were located inside the forest. Plot B was cut and burned in 1997. Plot C was inside a deforested 9-ha area, which was cut and burned in 1998. Plot D was inside a deforested 4-ha area, which was cut in 1998 and burned in 1999. Plot E was inside a deforested 4-ha area, which was cut and burned in 1999. Biomass consumption was 22.7%, 19.5%, 47.5%, 61.5%, and 41.8%, for A, B, C, D, and E, respectively. The effects of an extended curing period and of increasing the deforested area surrounding the plots could be clearly observed. The consumption, for areas cut and burned during the same year, tended toward a value of nearly 50% when presented as a function of the total area burned. The aboveground biomass of the test site and the amount of carbon before the fire were 496 Mg ha(-1) and 138 Mg ha(-1), respectively. Considering that the biomass that remains unburned keeps about the same average carbon content of fresh biomass, which is supported by the fact that the unburned material consists mainly of large logs, and considering the value of 50% for consumption, the amount of carbon released to the atmosphere as gases was 69 Mg ha(-1). The amounts of CO2 and CO released to the atmosphere by the burning process were then estimated as 228 Mg ha(-1) and 15.9 Mg ha(-1), respectively. Observations on fire propagation and general features of the slash burnings in the test areas complete the paper. | |||||
BibTeX:
@article{carvalho_biomass_2001, author = {Carvalho, J. A. and Costa, F. S. and Veras, C. A. G. and Sandberg, D. V. and Alvarado, E. C. and Gielow, R. and Serra, A. M. and Santos, J. C.}, title = {Biomass fire consumption and carbon release rates of rainforest-clearing experiments conducted in northern Mato Grosso, Brazil}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2001}, volume = {106}, number = {D16}, pages = {17877--17887}, url = {://WOS:000170579400012 http://www.agu.org/journals/jd/v106/iD16/2000JD900791/2000JD900791.pdf}, doi = {https://doi.org/10.1029/2000jd900791} } |
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Carvalho, G.O., Nepstad, D., McGrath, D., Diaz, M.D.V., Santilli, M. and Barros, A.C. | Frontier expansion in the Amzon: Balancing development and sustainability [BibTeX] |
2002 | Environment Vol. 44(3), pp. 34-45 |
article | URL |
BibTeX:
@article{carvalho_frontier_2002, author = {Carvalho, G. O. and Nepstad, D. and McGrath, D. and Diaz, M. D. V. and Santilli, M. and Barros, A. C.}, title = {Frontier expansion in the Amzon: Balancing development and sustainability}, journal = {Environment}, year = {2002}, volume = {44}, number = {3}, pages = {34--45}, url = {://WOS:000177568500006} } |
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Carvalho, G., Barros, A.C., Moutinho, P. and Nepstad, D. | Sensitive development could protect Amazonia instead of destroying it [BibTeX] |
2001 | Nature Vol. 409(6817), pp. 131-131 |
article | DOI URL |
BibTeX:
@article{carvalho_sensitive_2001, author = {Carvalho, G. and Barros, A. C. and Moutinho, P. and Nepstad, D.}, title = {Sensitive development could protect Amazonia instead of destroying it}, journal = {Nature}, year = {2001}, volume = {409}, number = {6817}, pages = {131--131}, note = {Edition: 2001/02/24}, url = {://WOS:000166316200013 http://www.nature.com/nature/journal/v409/n6817/pdf/409131a0.pdf}, doi = {https://doi.org/10.1038/35051794} } |
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Carvalho, A.M., Cunha Bustamante, M.M., Kozovits, A.R., de Miranda, L.N., Vivaldi, L.J. and de Sousa, D.M. | Nitrogen oxides emission related to urea broadcasting fertilization under conventional and no-tillage systems | 2006 | Pesquisa Agropecuaria Brasileira Vol. 41(4), pp. 679-685 |
article | URL |
Abstract: The objective of this work was to evaluate the NO and N2O emissions up to five days after the first nitrogen broadcasting fertilization with urea in a cornfield, in a Red Latosol, under conventional and no-tillage systems. The level of nitrogen broadcasting fertilization was of 60 kg ha(-1). The experiment was conducted at Embrapa Cerrados, Planaltina, DF, Brazil, in a randomized block design, with three replications, beeing the third corn crop in rotation with soybean. NO and N2O fluxes were measured using PVC chambers installed in each plot. Higher NO fluxes were found immediately after (5.4 ng N cm(-2) h(-1)) and three days (4.8 ng N cm(-2) h(-1)) after N fertilization and irrigation. In the first day after fertilization, the NO emission decreased significantly to 1.9 ng N cm(-2) h(-1), and after five days, reached 1.2 ng N cm(-2) h(-1). N2O fluxes values were below the detection limit of 0.6 ng N cm(-2) h(-1). No significant differences in nitrogen oxides fluxes were found between plots under conventional and no-tillage systems. | |||||
BibTeX:
@article{carvalho_nitrogen_2006, author = {Carvalho, Arminda Moreira and Cunha Bustamante, Mercedes Maria and Kozovits, Alessandra Rodrigues and de Miranda, Leo Nobre and Vivaldi, Lucio Jose and de Sousa, Danielle Matias}, title = {Nitrogen oxides emission related to urea broadcasting fertilization under conventional and no-tillage systems}, journal = {Pesquisa Agropecuaria Brasileira}, year = {2006}, volume = {41}, number = {4}, pages = {679--685}, url = {://WOS:000238923300020} } |
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Carvalho, A.M., Bustamante, M.M.C., Alcantara, F.A., Resck, I.S. and Lemos, S.S. | Characterization by solid-state CPMAS (13)C NMR spectroscopy of decomposing plant residues in conventional and no-tillage systems in Central Brazil | 2009 | Soil & Tillage Research Vol. 102(1), pp. 144-150 |
article | DOI URL |
Abstract: The Savanna region of Central Brazil is currently the most important area for grain production in the country but intensive agricultural activities are related to high losses of soil organic carbon. No-tillage systems were introduced in the mid 1980's but the use of cover plants in no-tillage systems is poorly studied and there is a demand for selection of suitable species to improve soil organic carbon. This study characterizes the chemical composition of decomposing plant residues of different cover plants (Crotalaria juncea, Canavalia brasiliensis, Cajanus cajan, Mucuna pruriens, Helianthus annuus, Pennisetum glaucum, Raphanus sativus and natural fallow, as a control). Cover plants were used in rotation with maize, under conventional and no-tillage systems. Decomposition rates were estimated using litter bags and residues of C. juncea, C. brasiliensis, M. pruriens and R. sativus were analyzed by CPMAS (13)C NMR. The highest decomposition rates were found for C. brasiliensis and C.juncea, while the lowest for M. pruriens, C. cajan and A glaucum. C. cajan presented the lowest content of polysaccharides and along with M. pruriens, the highest percentage of aromatic C, reflecting the slow decomposition of highly lignified material. The residues of these two species also presented high hydrophobicity, as a consequence of the presence of aromatic groups. Incorporation of plant residues accelerated the decomposition in comparison to no-tillage system. C. cajan, A glaucum and M. pruriens are more appropriate to increase soil cover due to lower decomposition rates while C. brasiliensis, R. sativus and H. annus, which presented higher decomposition rates, are indicated for an improvement of nutrient availability. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{carvalho_characterization_2009, author = {Carvalho, A. M. and Bustamante, M. M. C. and Alcantara, F. A. and Resck, I. S. and Lemos, S. S.}, title = {Characterization by solid-state CPMAS (13)C NMR spectroscopy of decomposing plant residues in conventional and no-tillage systems in Central Brazil}, journal = {Soil & Tillage Research}, year = {2009}, volume = {102}, number = {1}, pages = {144--150}, url = {://WOS:000262546800019}, doi = {https://doi.org/10.1016/j.still.2008.08.006} } |
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Carswell, F.E., Meir, P., Wandelli, E.V., Bonates, L.C.M., Kruijt, B., Barbosa, E.M., Nobre, A.D., Grace, J. and Jarvis, P.G. | Photosynthetic capacity in a central Amazonian rain forest | 2000 | Tree Physiology Vol. 20(3), pp. 179-186 |
article | URL |
Abstract: The vertical profile in leaf photosynthetic capacity was investigated in a terra firme rain forest in central Amazonia. Measurements of photosynthesis were made on leaves at five levels in the canopy, and a model was fitted to describe photosynthetic capacity for each level. In addition, vertical profiles of photosynthetic photon flux density, leaf nitrogen concentration and specific leaf area were measured. The derived parameters for maximum rate of electron transport (J(max)) and maximum rate of carboxylation by Rubisco (V-cmax) increased significantly with canopy height (P textless 0.05). The highest J(max) for a single canopy level was measured at the penultimate canopy level (20 m) and was 103.9 mu mol m(-2) s(-1) +/- 24.2 (SE). The highest V-cmax per canopy height was recorded at the top canopy level (24 m) and was 42.8 +/- 5.9 mu mol m(-2) s(-1). Values of J(max) and V-cmax at ground level were 35.8 +/- 3.3 and 20.5 +/- 1.3 mu mol m(-2) s(-1), respectively. The increase in photosynthetic capacity with increasing canopy height was strongly correlated with leaf nitrogen concentration when examined on a leaf area basis, but was only weakly correlated on a mass basis. The correlation on an area basis can be largely explained by the concomitant decrease in specific leaf area with increasing height. Apparent daytime leaf respiration, on an area basis, also increased significantly with canopy height (P textless 0.05). We conclude that canopy photosynthetic capacity can be represented as an average vertical profile, perturbations of which may be explained by variations in the environmental variables driving photosynthesis. | |||||
BibTeX:
@article{carswell_photosynthetic_2000, author = {Carswell, F. E. and Meir, P. and Wandelli, E. V. and Bonates, L. C. M. and Kruijt, B. and Barbosa, E. M. and Nobre, A. D. and Grace, J. and Jarvis, P. G.}, title = {Photosynthetic capacity in a central Amazonian rain forest}, journal = {Tree Physiology}, year = {2000}, volume = {20}, number = {3}, pages = {179--186}, url = {://WOS:000085664900004} } |
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Carswell, F.E., Costa, A.L., Palheta, M., Malhi, Y., Meir, P., Costa, J.D.R., Ruivo, M.D., Leal, L.D.M., Costa, J.M.N., Clement, R.J. and Grace, J. | Seasonality in CO2 and H2O flux at an eastern Amazonian rain forest | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Previous studies of CO2 fluxes in Amazonia have suggested seasonal variation in net ecosystem exchange. We find little evidence of this seasonality at a new site in eastern Amazonia, despite the expectation that this site would be particularly sensitive to seasonal fluctuation of rainfall. The average rate of peak net ecosystem exchange was -19 +/- 0.9 (1 S. E.) m mol CO2 m(-2) s(-1). Canopy conductance, evaporation, and vapour pressure deficit were all increased during the dry season, consistent with an increase in bulk temperature and solar radiation. The lack of a dry season decrease in photosynthesis was thought to be due to the observed increase in leaf area following dry season flushing. This was accompanied by an increase in solar radiation, and we suggest that the effect of "dryness" was merely to preclude optimality of photosynthetic response to this increase in radiation. The gross primary productivity of this site was estimated to be 36 t C ha(-1) yr(-1). This is similar to that reported for other Amazon forest stands. The year may have been a particularly productive one due to the lack of an El Nino event. | |||||
BibTeX:
@article{carswell_seasonality_2002, author = {Carswell, F. E. and Costa, A. L. and Palheta, M. and Malhi, Y. and Meir, P. and Costa, J. D. R. and Ruivo, M. D. and Leal, L. D. M. and Costa, J. M. N. and Clement, R. J. and Grace, J.}, title = {Seasonality in CO2 and H2O flux at an eastern Amazonian rain forest}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200037}, doi = {https://doi.org/10.1029/2000jd00284} } |
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Carreiras, J.M.B., Shimabukuro, Y.E. and Pereira, J.M.C. | Fraction images derived from SPOT-4 VEGETATION data to assess land-cover change over the State of Mato Grosso, Brazil [BibTeX] |
2002 | International Journal of Remote Sensing Vol. 23(23), pp. 4979-4983 |
article | DOI URL |
BibTeX:
@article{carreiras_fraction_2002, author = {Carreiras, J. M. B. and Shimabukuro, Y. E. and Pereira, J. M. C.}, title = {Fraction images derived from SPOT-4 VEGETATION data to assess land-cover change over the State of Mato Grosso, Brazil}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {23}, pages = {4979--4983}, url = {://WOS:000179940500001}, doi = {https://doi.org/10.1080/0143116021000016743} } |
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Carreiras, J.M.B., Pereira, J.M.C., Shimabukuro, Y.E. and Stroppiana, D. | Evaluation of compositing algorithms over the Brazilian Amazon using SPOT-4 VEGETATION data | 2003 | International Journal of Remote Sensing Vol. 24(17), pp. 3427-3440 |
article | DOI URL |
Abstract: The main objective of this study is to evaluate several algorithms to produce monthly composite images of the VEGETATION sensor onboard SPOT-4 over the Brazilian Amazon. The ability of the commonly used Normalized Difference Vegetation Index maximum value composite (MNDVI) and other compositing algorithms (i.e. one- and/or two-step algorithms), in terms of reducing the presence of clouds and cloud shadows and assessing spatial coherence of the composite images was tested. Among the one-step algorithms, the Soil Adjusted Vegetation Index maximum value composite (MSAVI), the minimum value composite of the red band (mRed) and the minimum value composite of the red band with an additional temporal persistence condition (mRedtp) were also analysed. The two-step algorithms included MNDVI or MSAVI followed by the minimum value of the viewing zenith angle, and mRed followed by MNDVI or by MSAVI. These eight compositing algorithms were used to produce monthly (August 2000) composite images of four regions (200 km x 200 km) representative of different landscape structures in the Brazilian Amazon. The results show that none of the compositing algorithms consistently performs best over all the regions. However, at this stage of the assessment, mRedMNDVI and mRedMSAVI are good candidates for SPOT-4 VGT monthly compositing over the Brazilian Amazon. | |||||
BibTeX:
@article{carreiras_evaluation_2003, author = {Carreiras, J. M. B. and Pereira, J. M. C. and Shimabukuro, Y. E. and Stroppiana, D.}, title = {Evaluation of compositing algorithms over the Brazilian Amazon using SPOT-4 VEGETATION data}, journal = {International Journal of Remote Sensing}, year = {2003}, volume = {24}, number = {17}, pages = {3427--3440}, url = {://WOS:000184184000006}, doi = {https://doi.org/10.1080/0143116021000021251} } |
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Carr, D.L., Pan, W.K.Y. and Bilsborrow, R.E. | Declining fertility on the frontier: the Ecuadorian Amazon | 2006 | Population and Environment Vol. 28(1), pp. 17-39 |
article | DOI URL |
Abstract: This paper examines farm and household characteristics associated with a rapid fertility decline in a forest frontier of the Ecuadorian Amazon. The Amazon basin and other rainforests in the tropics are among the last frontiers in the ongoing global fertility transition. The pace of this transition along agricultural frontiers will likely have major implications for future forest transitions, rural development, and ultimately urbanization in frontier areas. The study here is based upon data from a probability sample of 172 women who lived on the same farm in 1990 and 1999. These data are from perhaps the first region-wide longitudinal survey of fertility in an agricultural frontier. Descriptive analyses indicate that fertility has plummeted in the region, which is surprising since it had remained high and unchanging among migrant colonists up to 1990. Thus only half of the women in our sample reported having a birth during the 1990-1999 time period, and most women report in 1999 that they do not want to have any more children. Analyses, controlling for women's age, corroborate hypotheses about land-fertility relations. For example, women from households with a legal land title had fewer than half as many children as those from households without a title. Large cattle (pasture) holdings and hiring laborers to work on the farm (which may replace household labor) are both related to socio-economic status that is traditionally associated with lower fertility. Similarly, distance to the nearest community center is positively related to fertility. Factors negatively related to fertility include increasing temporary out-migration of adult men or women from the household, asset accumulation, and access to electricity. | |||||
BibTeX:
@article{carr_declining_2006, author = {Carr, David L. and Pan, William K. Y. and Bilsborrow, Richard E.}, title = {Declining fertility on the frontier: the Ecuadorian Amazon}, journal = {Population and Environment}, year = {2006}, volume = {28}, number = {1}, pages = {17--39}, url = {://WOS:000245798100002 http://www.springerlink.com/content/y78126u71n5630l0/fulltext.pdf}, doi = {https://doi.org/10.1007/s11111-007-0032-y} } |
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Carneiro, R.G. and Fisch, G. | Observational analysis of the daily cycle of the planetary boundary layer in the central Amazon during a non-El Niño year and El Niño year (GoAmazon project 2014/5) [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(9), pp. 5547-5558 |
article | DOI URL |
BibTeX:
@article{carneiro_observational_2020, author = {Carneiro, R. G. and Fisch, G.}, title = {Observational analysis of the daily cycle of the planetary boundary layer in the central Amazon during a non-El Niño year and El Niño year (GoAmazon project 2014/5)}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {9}, pages = {5547--5558}, url = {https://acp.copernicus.org/articles/20/5547/2020/}, doi = {https://doi.org/10.5194/acp-20-5547-2020} } |
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Carmo, J.B., Piccolo, M.d.C., de Andrade, C.A., Pellegrino Cerri, C.E., Feigl, B.J., Sousa Neto, E. and Cerri, C.C. | Short-term changes in nitrogen availability, gas fluxes (CO2, NO, N2O) and microbial biomass after tillage during pasture re-establishment in Rondonia, Brazil | 2007 | Soil & Tillage Research Vol. 96(1-2), pp. 250-259 |
article | DOI URL |
Abstract: Anthropogenic conversion of primary forest to pasture for cattle production is still frequent in the Amazon Basin. Practices adopted by ranchers to restore productivity to degraded pasture have the potential to alter soil N availability and N gas losses from soils. We examined short-term (similar to 35 days) effects of tillage prior to pasture re-establishment on soil N availability, CO2, NO and N2O fluxes and microbial biomass C and N under degraded pasture at Nova Vida ranch, Rondonia, Brazilian Amazon. We collected soil samples and measured gas fluxes in tilled and control (non tilled pasture) 12 times at equally spaced intervals during October 2001 to quantify the effect of tillage. Maximum soil NH4+ and NO3- pools were 13.2 and 6.3 kg N ha(-1) respectively after tillage compared to 0.24 and 6.3 kg N ha(-1) in the control. Carbon dioxide flux ranged from I IS to 181 mg C-Co-2 m(2)h(-1) in the control (non-tilled) and from 110 to 235 mg C-CO, m 2 h(-1) when tilled. Microbial biomass C varied from 365 to 461 mu g g(-1) in the control and from 248 to 535 mu g g(-1) when tilled. The values for N,O fluxes ranged from 1.22 to 96.9 mu g N m(-2) h(-1) in the tilled plots with a maximum 3 days after the second tilling. Variability in NO flux in the control and when tilled was consistent with previous measures of NO emissions from pasture at Nova Vida. When tilled, the NO/N2O ratio remained textless 1 after the first tilling suggesting that denitrification dominated N cycling. The effects of filling on microbial parameters were less clear, except for a decrease in qCO(2) and an increase in microbial biomass C/N immediately after tilling. Our results suggest that restoration of degraded pastures with tillage will lead to less C matter, at least initially. Further long-term research is needed. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{carmo_short-term_2007, author = {Carmo, Janaina Braga and Piccolo, Marisa de Cassia and de Andrade, Cristiano Alberto and Pellegrino Cerri, Carlos Eduardo and Feigl, Brigitte Josefine and Sousa Neto, Eraclito and Cerri, Carlos Clemente}, title = {Short-term changes in nitrogen availability, gas fluxes (CO2, NO, N2O) and microbial biomass after tillage during pasture re-establishment in Rondonia, Brazil}, journal = {Soil & Tillage Research}, year = {2007}, volume = {96}, number = {1-2}, pages = {250--259}, url = {://WOS:000250689400025}, doi = {https://doi.org/10.1016/j.still.2007.06.002} } |
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Carmo, J.B. and Pellegrino Cerri, C.E. | Nitrogen dynamics in forestry and grassland soils in the Amazon region - A review | 2007 | Outlook on Agriculture Vol. 36(1), pp. 41-48 |
article | URL |
Abstract: The main economical land use in the Amazon since the 1970s has been as cattle pastures, which are largely the result of widespread deforestation. Estimates indicate that approximately 120,000 km(2) of pastures show some degree of degradation, which will require the opening up of new areas of forest. The authors' conclusions are as follows: (1) The quality of organic matter in the forage grasses modifies N cycling in relation to that originally present in forest soils. (2) In cases where N availability in the soil is not limited to the soil microbiological processes, other soil parameters, such as humidity, start to control N(2)O fluxes to the atmosphere. (3) Tillage and fertilization induce higher nitrate availability in the short term, but this could be synchronized with plant uptake, which would lead to fewer losses from leaching, plus soil denitrification rates would also decrease and would not support N loss in gaseous form. Any degraded pasture recovery strategy that affects available soil N content will also indirectly influence atmospheric N(2)O flux. When N availability is not a limitation to soil biological processes, water content changes and other soil properties become important N(2)O flux controllers. (4) If these conditions are acknowledged, there can be a higher level of sustainability and more effective development of the system and productivity can be achieved. | |||||
BibTeX:
@article{carmo_nitrogen_2007, author = {Carmo, Janaina Braga and Pellegrino Cerri, Carlos Eduardo}, title = {Nitrogen dynamics in forestry and grassland soils in the Amazon region - A review}, journal = {Outlook on Agriculture}, year = {2007}, volume = {36}, number = {1}, pages = {41--48}, url = {://WOS:000245509300006} } |
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Carmo, J.B., Neill, C., Garcia-Montiel, D.C., Piccolo, M.D., Cerri, C.C., Steudler, P.A., de Andrade, C.A., Passianoto, C.C., Feigl, B.J. and Melillo, J.M. | Nitrogen dynamics during till and no-till pasture restoration sequences in Rondonia, Brazil | 2005 | Nutrient Cycling in Agroecosystems Vol. 71(3), pp. 213-225 |
article | DOI URL |
Abstract: The clearing of tropical rain forest in the Amazon basin has created large areas of cattle pasture that are now declining in productivity. Practices adopted by ranchers to restore productivity to degraded pastures have the potential to alter soil N availability and gaseous N losses from soils. We examined how soil inorganic N pools, net N mineralization and net nitrification rates, nitrification potential and NO and N2O emissions from soils of a degraded pasture responded to the following restoration treatments: ( 1) soil tillage followed by replanting of grass and fertilization, ( 2) no-till application of non-selective herbicide, planting of rice, harvest followed by no-till replanting of grass and fertilization, and ( 3) the same no-till sequence with soybeans instead of rice. Tillage increased soil NH4+ and NO3- pools but NH4+ and NO3- pools remained relatively constant in the control and no-till treatments. Cumulative rates of net N mineralization and net nitrification during the first 6 months after treatment varied widely but were hightest in the tilled treatment. Emissions of NO and N2O fluxes increased with tillage and with N fertilization. There were no clear relationships among rates of N fertilizer application, net N mineralization, net nitrification, NO, N2O and total N oxide emissions. Our results indicate that pasture restoration sequences involving tilling and fertilizing will increase emissions of N oxides, but the magnitude of the increase is likely to differ based on timing of fertilizer application relative to the presence of plants and the magnitude of plant N demand. Emissions of N oxides appear to be decreased by the use of restoration sequences that minimize reductions in pasture grass cover. | |||||
BibTeX:
@article{carmo_nitrogen_2005, author = {Carmo, J. B. and Neill, C. and Garcia-Montiel, D. C. and Piccolo, M. D. and Cerri, C. C. and Steudler, P. A. and de Andrade, C. A. and Passianoto, C. C. and Feigl, B. J. and Melillo, J. M.}, title = {Nitrogen dynamics during till and no-till pasture restoration sequences in Rondonia, Brazil}, journal = {Nutrient Cycling in Agroecosystems}, year = {2005}, volume = {71}, number = {3}, pages = {213--225}, url = {://WOS:000229627500001 http://www.springerlink.com/content/h37j676l7t17v634/fulltext.pdf}, doi = {https://doi.org/10.1007/s10705-004-2213-8} } |
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Carmo, J.B., Keller, M., Dias, J.D., de Camargo, P.B. and Crill, P. | A source of methane from upland forests in the Brazilian Amazon | 2006 | Geophysical Research Letters Vol. 33(4) |
article | DOI URL |
Abstract: We sampled air in the canopy layer of undisturbed upland forests during wet and dry seasons at three sites in the Brazilian Amazon region and found that both methane (CH(4)) and carbon dioxide (CO(2)) mixing ratios increased at night. Such increases were consistent across sites and seasons. A canopy layer budget model based on measured soil-atmosphere fluxes of CO(2) was constructed to estimate ecosystem CH(4) emission. We estimate that net CH(4) emission in upland forests ranged from 2 to 21 mg CH(4) m(-2) d(-1). While the origin of this CH(4) source is unknown, these ground based measurements are consistent with recent findings based on satellite observations that indicate a large, unidentified source of CH(4) in tropical forest regions. | |||||
BibTeX:
@article{carmo_source_2006, author = {Carmo, J. B. and Keller, M. and Dias, J. D. and de Camargo, P. B. and Crill, P.}, title = {A source of methane from upland forests in the Brazilian Amazon}, journal = {Geophysical Research Letters}, year = {2006}, volume = {33}, number = {4}, url = {://WOS:000235993200005 http://www.agu.org/pubs/crossref/2006/2005GL025436.shtml}, doi = {https://doi.org/10.1029/2005gl025436} } |
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Carmo, J.B., de Andrade, C.A., Cerri, C.C. and Piccolo, M.D. | Nitrogen availability and N2O fluxes frompasture soil after herbicide application | 2005 | Revista Brasileira De Ciencia Do Solo Vol. 29(5), pp. 735-746 |
article | URL |
Abstract: NITROGEN AVAILABILITY AND N2O FLUXES FROM PASTURE SOIL AFTER HERBICIDE APPLICATION Nitrous Oxide (N2O) plays an important role in the greenhouse effect, owing to its high global warming potential and a long half-life in the atmosphere. A large portion of the natural N2O flux is oceanic and the remaining results mainly from the contribution of microbiological processes (nitrification and denitrification) that occur in tropical soils. The availability of nitrogen (N) for metabolic processes by microorganisms may be an important factor controlling N2O in such soils. The goal of this study was to improve the understanding of mechanisms controlling N2O fluxes from soils under pasture in the Amazon. We investigated the effects of N and carbon (C) availability, and soil moisture on N2O emission from, two different pastures (with or without treatments for recovery of productivity). The study was developed under laboratory conditions by incubating soil samples from the following pastures: (a) Control - Soil from a traditionally-managed pasture established in 1983 consisting of a mixture of Brachiaria brizantha and Panicum maximum, besides a type of weed; and (b) Herbicide treated - total desiccation of pasture established in 1983 in preparation for cultivation of no-till rice and posterior grass replanting. It is important to emphasize that soil samples (0-5 cm depth) were collected on the third day after herbicide application. To compare and understand N2O fluxes, we added nitrate, dextrose and water to the soil before incubation and used acetylene to block N2O oxidation to N-2, in order to estimate the N-2 emitted from the soil. The highest fluxes were observed when nitrate was added to the soil under high moisture conditions. Dextrose (C source) addition increased fluxes at more extent in the soil from the pasture that received herbicide application and also displayed higher N availability. With acetylene application it was possible to observe that a large portion of N lost in gaseous forms occurs as N-2. Thus, in the studied pasture the denitrification process appeared to be dominated by N2O soil fluxes and N was the main factor controlling these fluxes. | |||||
BibTeX:
@article{carmo_nitrogen_2005-1, author = {Carmo, J. B. and de Andrade, C. A. and Cerri, C. C. and Piccolo, M. D.}, title = {Nitrogen availability and N2O fluxes frompasture soil after herbicide application}, journal = {Revista Brasileira De Ciencia Do Solo}, year = {2005}, volume = {29}, number = {5}, pages = {735--746}, url = {://WOS:000233211300009} } |
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Carmo, C.N.d., Hacon, S., Longo, K.M., Freitas, S., Ignotti, E., de Leon, A.P. and Artaxo, P. | Association between particulate matter from biomass burning and respiratory diseases in the southern region of the Brazilian Amazon | 2010 | Revista Panamericana De Salud Publica-Pan American Journal of Public Health Vol. 27(1), pp. 10-16 |
article | URL |
Abstract: Objective. To investigate the short-term effects of exposure to particulate matter from biomass burning in the Amazon on the daily demand for outpatient care due to respiratory diseases in children and the elderly. Methods. Epidemiologic study with ecologic time series design. Daily consultation records were obtained from the 14 primary health care clinics in the municipality of Alta Floresta, state of Mato Grosso, in the southern region of the Brazilian Amazon, between January 2004 and December 2005. Information on the daily levels of fine particulate matter was made available by the Brazilian National Institute for Spatial Research. To control for confounding factors ( situations in which a non-causal association between exposure and disease is observed due to a third variable), variables related to time trends, seasonality, temperature, relative humidity, rainfall, and calendar effects ( such as occurrence of holidays and weekends) were included in the model. Poisson regression with generalized additive models was used. Results. A 10 mu g/m(3) increase in the level of exposure to particulate matter was associated with increases of 2.9% and 2.6% in outpatient consultations due to respiratory diseases in children on the 6th and 7th days following exposure. Significant associations were not observed for elderly individuals. Conclusions. The results suggest that the levels of particulate matter from biomass burning in the Amazon are associated with adverse effects on the respiratory health of children. | |||||
BibTeX:
@article{carmo_association_2010, author = {Carmo, Cleber Nascimento do and Hacon, Sandra and Longo, Karla Maria and Freitas, Saulo and Ignotti, Eliane and de Leon, Antonio Ponce and Artaxo, Paulo}, title = {Association between particulate matter from biomass burning and respiratory diseases in the southern region of the Brazilian Amazon}, journal = {Revista Panamericana De Salud Publica-Pan American Journal of Public Health}, year = {2010}, volume = {27}, number = {1}, pages = {10--16}, url = {://WOS:000275325100002} } |
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Carlos A. Quesada, J.L. | Soil-Vegetation Interactions in Amazonia [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 267-299 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_soil-vegetation_2016, author = {Carlos A. Quesada, Jon Lloyd}, title = {Soil-Vegetation Interactions in Amazonia}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {267--299}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Cardoso, M.F., Nobre, C.A., Lapola, D.M., Oyama, M.D. and Sampaio, G. | Long-term potential for fires in estimates of the occurrence of savannas in the tropics | 2008 | Global Ecology and Biogeography Vol. 17(2), pp. 222-235 |
article | DOI URL |
Abstract: Aim This study aims to improve the formulation and results of the Brazilian Center for Weather Forecasting and Climate Studies Potential Vegetation Model (CPTEC-PVM) by developing a new parameterization for the long-term occurrence of fire in regions of potential savannas in the tropics. Compared with the relatively slow processes of carbon uptake and growth in vegetation, fast mortality and biomass consumption by fires may favour grasses and reduce tree coverage. Location The tropics. Methods For finding large-scale relationships between fires and other environmental factors, we made two main simplifying assumptions. First, lightning is the most important source of ignition for natural fires. Second, over continental areas in the tropics, lightning is mainly related to the zonal flux of moisture transport. Results The parameterization of fire occurrence was built based on a simple empirical relationship, combining information on mean and intra-annual variance of the zonal wind. Main conclusions The implementation of this new relationship improved the formulation and the results of the CPTEC-PVM. As a result of this new parameter, the accuracy of the model in allocating the correct vegetation (seasonal forests) instead of savannas for large regions in India and Southeast Asia is now substantially higher than in previous studies. | |||||
BibTeX:
@article{cardoso_long-term_2008, author = {Cardoso, Manoel F. and Nobre, Carlos A. and Lapola, David M. and Oyama, Marcos D. and Sampaio, Gilvan}, title = {Long-term potential for fires in estimates of the occurrence of savannas in the tropics}, journal = {Global Ecology and Biogeography}, year = {2008}, volume = {17}, number = {2}, pages = {222--235}, url = {://WOS:000252966000008 http://onlinelibrary.wiley.com/store/10.1111/j.1466-8238.2007.00356.x/asset/j.1466-8238.2007.00356.x.pdf?v=1&t=h6hyfiou&s=6aa2afd96a33be9a4af575b5d3156c76656e26b1}, doi = {https://doi.org/10.1111/j.1466-8238.2007.00356.x} } |
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Cardoso, M.F., Hurtt, G.C., Moore, B., Nobre, C.A. and Prins, E.M. | Projecting future fire activity in Amazonia | 2003 | Global Change Biology Vol. 9(5), pp. 656-669 |
article | DOI URL |
Abstract: Fires are major disturbances for ecosystems in Amazonia. They affect vegetation succession, alter nutrients and carbon cycling, and modify the composition of the atmosphere. Fires in this region are strongly related to land-use, land-cover and climate conditions. Because these factors are all expected to change in the future, it is reasonable to expect that fire activity will also change. Models are needed to quantitatively estimate the magnitude of these potential changes. Here we present a new fire model developed by relating satellite information on fires to corresponding statistics on climate, land-use and land-cover. The model is first shown to reproduce the main contemporary large-scale features of fire patterns in Amazonia. To estimate potential changes in fire activity in the future, we then applied the model to two alternative scenarios of development of the region. We find that in both scenarios, substantial changes in the frequency and spatial patterns of fires are expected unless steps are taken to mitigate fire activity. | |||||
BibTeX:
@article{cardoso_projecting_2003, author = {Cardoso, M. F. and Hurtt, G. C. and Moore, B. and Nobre, C. A. and Prins, E. M.}, title = {Projecting future fire activity in Amazonia}, journal = {Global Change Biology}, year = {2003}, volume = {9}, number = {5}, pages = {656--669}, url = {://WOS:000182653700002 http://onlinelibrary.wiley.com/store/10.1046/j.1365-2486.2003.00607.x/asset/j.1365-2486.2003.00607.x.pdf?v=1&t=h6hyf0e0&s=f978bba0b0a15bd4742c5ca6a768a1ab2125b884}, doi = {https://doi.org/10.1046/j.1365-2486.2003.00607.x} } |
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Cardoso, M.F., Hurtt, G.C., Moore, B., Nobre, C.A. and Bain, H. | Field work and statistical analyses for enhanced interpretation of satellite fire data | 2005 | Remote Sensing of Environment Vol. 96(2), pp. 212-227 |
article | DOI URL |
Abstract: Because their broad spatial and temporal coverage, satellites provide the main source of fire data for Amazonia. A key to the application of these tools for environmental studies is the appropriate interpretation of the data they provide. To enhance the interpretation of satellite fire data for this region, we collected ground-based data on fires in 2001 and 2002 using a simple and passive method, and statistically related these data to corresponding estimates from AVHRR and MODIS fire products using error matrices. Multiple methods of analyses from simple to complex produced qualitatively similar results. Total accuracies for both fire products were very high (textgreater 99%) and dominated by accurate (textgreater 99%) non-fire detection. Kappa statistics and fire-detection accuracies were substantially lower, with omission errors higher than commission errors. Results calculated using several different sets of spatial-matching parameters of analysis showed that Kappa was 1-10.6% for AVHRR, and 0-1.4% for MODIS. User's accuracy for fires was 0-40% for AVHRR and 3-100% for MODIS. Producer's accuracy for fires was 0-8% for AVHRR and 0-1% for MODIS. Statistical evaluations of potential explanatory factors showed that fire size and sampling time were dominant factors for low accuracies. Results from this study indicate that current satellite fire products are providing a limited sample of the fire activity in the region, and that ground-based analyses can substantially contribute to the interpretation of these products. (c) 2005 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{cardoso_field_2005, author = {Cardoso, M. F. and Hurtt, G. C. and Moore, B. and Nobre, C. A. and Bain, H.}, title = {Field work and statistical analyses for enhanced interpretation of satellite fire data}, journal = {Remote Sensing of Environment}, year = {2005}, volume = {96}, number = {2}, pages = {212--227}, url = {://WOS:000230284800007}, doi = {https://doi.org/10.1016/j.rse.2005.02.008} } |
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Cardille, J.A., Foley, J.A. and Costa, M.H. | Characterizing patterns of agricultural land use in Amazonia by merging satellite classifications and census data | 2002 | Global Biogeochemical Cycles Vol. 16(3) |
article | DOI URL |
Abstract: [1] Amazonia has been under considerable development pressure as croplands and pasture are established in areas formerly occupied by tropical forest and cerrado. Although this region is an important part of several important planetary biogeochemical cycles, the location and impact of human land use are not well understood. In particular, there is no existing satellite-based map of agriculture across the Amazon or Tocantins river drainage basins. Recent efforts have classified land cover across this vast region, although they disagree on the location and amount of cropland and do not directly address pasture, a land use that has grown in importance in the last 2 decades. Here we present an analysis of land cover and land use practices over the Amazon and Tocantins basins of South America. In this study, we demonstrate how satellite imagery and agricultural censuses can be merged in order to provide a geographically explicit, fine-scale description of land cover and land use practices. The result depicts the fraction of each 5-min (9 x 9 km) grid cell that was devoted to agricultural activity during the mid-1990s. The resultant map retains many of the characteristics of the agricultural census data, but with a much finer spatial resolution. During the mid-1990s, cultivated area is estimated to have been 1.7 x 10(7) ha (2.5% of the basin), natural pasture is estimated at 3.3 x 10(7) ha (4.9% of the basin), and planted pasture is estimated to cover 3.3 x 10(7) ha (4.9% of the basin). Perhaps more important than the quantities, however, is that these data sets provide a new blend of ground-based and satellite-based spatially explicit data. This snapshot can be used as a basis to project either forward or backward in time, as a new check of finer scale land use classifications or as a driver of ecosystem models. | |||||
BibTeX:
@article{cardille_characterizing_2002, author = {Cardille, J. A. and Foley, J. A. and Costa, M. H.}, title = {Characterizing patterns of agricultural land use in Amazonia by merging satellite classifications and census data}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {3}, url = {://WOS:000179008700001 http://www.agu.org/pubs/crossref/2002/2000GB001386.shtml}, doi = {https://doi.org/10.1029/2000gb001386} } |
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Carbone, S., Timonen, H.J., Rostedt, A., Happonen, M., Rönkkö, T., Keskinen, J., Ristimaki, J., Korpi, H., Artaxo, P., Canagaratna, M., Worsnop, D., Canonaco, F., Prévôt, A.S.H., Hillamo, R. and Saarikoski, S. | Distinguishing fuel and lubricating oil combustion products in diesel engine exhaust particles [BibTeX] |
2019 | Aerosol Science and Technology Vol. 17, pp. 1-17 |
article | |
BibTeX:
@article{carbone_distinguishing_2019, author = {Carbone, Samara and Timonen, Hilkka J. and Rostedt, Antti and Happonen, Matti and Rönkkö, Topi and Keskinen, Jorma and Ristimaki, Jyrki and Korpi, Heikki and Artaxo, Paulo and Canagaratna, Manjula and Worsnop, Douglas and Canonaco, Francesco and Prévôt, Andre S. H. and Hillamo, Risto and Saarikoski, Sanna}, title = {Distinguishing fuel and lubricating oil combustion products in diesel engine exhaust particles}, journal = {Aerosol Science and Technology}, year = {2019}, volume = {17}, pages = {1--17} } |
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Caraballo, P., Forsberg, B. and Leite, R. | Variación estacional de la distribución e composición isotópica del fitoplâncton em um lago de inundación em la Amazonia, Brasil [BibTeX] |
2014 | Acta Biológica Colombiana Vol. 19, pp. 291-304 |
article | |
BibTeX:
@article{caraballo_variacion_2014, author = {Caraballo, P. and Forsberg, B.R. and Leite, R.G.}, title = {Variación estacional de la distribución e composición isotópica del fitoplâncton em um lago de inundación em la Amazonia, Brasil}, journal = {Acta Biológica Colombiana}, year = {2014}, volume = {19}, pages = {291--304} } |
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Caraballo, P., Forsberg, B., Almeida, F.F. and Leite, R. | Diel patterns of temperature,conductivity and dissolved oxygen in an Amazon floodplain lake: description of a friagem phenomenon [BibTeX] |
2014 | Acta Limnologica Brasiliensia Vol. 26, pp. 318-331 |
article | |
BibTeX:
@article{caraballo_diel_2014, author = {Caraballo, P. and Forsberg, B.R. and F.F., Almeida and Leite, R.G.}, title = {Diel patterns of temperature,conductivity and dissolved oxygen in an Amazon floodplain lake: description of a friagem phenomenon}, journal = {Acta Limnologica Brasiliensia}, year = {2014}, volume = {26}, pages = {318--331} } |
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Candido, L.A., Sousa, J.M.d., Silva, J.T.d. and Manzi, A.O. | Cenários Climáticos para Amazônia [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 105-112 |
incollection | |
BibTeX:
@incollection{emilio_cenarios_2014-2, author = {Candido, Luiz Antonio and Sousa, Jeanne Moreira de and Silva, Júlio Tota da and Manzi, Antonio Ocimar}, title = {Cenários Climáticos para Amazônia}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {105--112}, note = {Section: 9} } |
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Cândido, S., R.V.A., M., M.T.F., M., Luizão, A.O., Saragoussi, F.J. and L.A., M. | Desvendando a Ciência do Clima [BibTeX] |
2014 | , pp. 29p.School: INPA | techreport | |
BibTeX:
@techreport{candido_desvendando_2014, author = {Cândido, Souza, R.V.A., Monteiro, M.T.F., Manzi, A.O., Luizão, F.J., Saragoussi, M., L.A.}, title = {Desvendando a Ciência do Clima}, school = {INPA}, year = {2014}, pages = {29p.}, note = {Edition: PRONEX/FAPEAM} } |
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Candido, G., Manzi, M.A. and L., A.O. | Sensibilidade da Zona de Convergência do Atlântico Sul (ZCAS) à condição hídrica do solo: um estudo de caso [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3b) |
article | |
BibTeX:
@article{candido_sensibilidade_2006, author = {Candido, Gan, M.A., Manzi, A.O., L.}, title = {Sensibilidade da Zona de Convergência do Atlântico Sul (ZCAS) à condição hídrica do solo: um estudo de caso}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3b} } |
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Campos, M.T. and Nepstad, D.C. | Smallholders, the Amazon's new conservationists [BibTeX] |
2006 | Conservation Biology Vol. 20(5), pp. 1553-1556 |
article | DOI URL |
BibTeX:
@article{campos_smallholders_2006, author = {Campos, Mamna T. and Nepstad, Daniel C.}, title = {Smallholders, the Amazon's new conservationists}, journal = {Conservation Biology}, year = {2006}, volume = {20}, number = {5}, pages = {1553--1556}, note = {Edition: 2006/09/28}, url = {://WOS:000241031600029}, doi = {https://doi.org/10.1111/j.1523-1739.2006.00546} } |
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Campos, M.S., Adami, M. and Araújo, A.C.d. | Análise do Albedo de Superfície da Palma de óleo e Diferentes Usos e Coberturas do Solo no Leste da Amazônia | 2021 | Revista Brasileira de Meteorologia Vol. 36(1), pp. 15-21 |
article | DOI URL |
Abstract: In recent years there has been a continuous advance of the agricultural frontier of oil palm in the Amazon region, which causes changes in soil cover in this region. Given the need to understand the influence of this crop on surface albedo, the present study aims to compare the fluctuations of surface albedo in oil palm culture area with those of pasture, forest and secondary vegetation. To make this comparison, orbital data based on Terra / MODIS satellite product MCD43A3 for the years 2015 and 2016 were used. The samples selected for the study area showed that the oil palm showed little variation, estimating values medium α = 0.14, being statistically distinct from other uses and coverings, with the albedo: Pasture textgreater Palm Oil textgreater Secondary Vegetation textgreater Forest. Demonstrating that possible conversions from one cover to another can influence the surface radiation balance, ie if oil palm cultivation continues to advance over pasture areas, this would decrease surface albedo and consequently have microclimate changes, however. If expansion occurs over areas of Secondary Vegetation or Forest an inversion will occur and may contribute to climate change. Resumo Nos últimos anos tem-se verificado um contínuo avanço da fronteira agrícola da palma de óleo na região amazônica, o que provoca alterações na cobertura do solo nessa região. Diante da necessidade de se compreender a influência deste cultivo no albedo de superfície, o presente estudo visa comparar as flutuações do albedo de superfície em área de cultura de palma de óleo com os de pastagem, floresta e de vegetação secundária. Para fazer esta comparação foi utilizado dados orbitais, com base no produto MCD43A3 do satélite Terra/MODIS para os anos de 2015 e 2016. As amostras selecionadas para área de estudo mostrou que a palma de óleo obteve pouca variação, estimando valores médios α = 0.14, sendo estatisticamente distinto dos outros usos e coberturas, com o albedo: Pastagem textgreater Palma de óleo textgreater Vegetação Secundária textgreater Floresta. Demonstrando que possíveis conversões de uma cobertura para outra podem influenciar no balanço de radiação na superfície, ou seja, caso o cultivo da palma de óleo continue avançando sobre as áreas de pastagem, isto diminuiria o albedo de superfície e consequentemente teria mudanças no microclima, todavia, se a expansão ocorrer sobre áreas de Vegetação Secundária ou Floresta ocorrerá uma inversão, e poderá contribuir para alterações climáticas. |
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BibTeX:
@article{campos_alise_2021, author = {Campos, Mayara Soares and Adami, Marcos and Araújo, Alessandro Carioca de}, title = {Análise do Albedo de Superfície da Palma de óleo e Diferentes Usos e Coberturas do Solo no Leste da Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2021}, volume = {36}, number = {1}, pages = {15--21}, url = {http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-77862021000100015&lang=pt}, doi = {https://doi.org/10.1590/0102-77863540071} } |
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Campos, M.D.R., Aquino, R.E., Santos, L.A.C., Mantovanelli B. C. ., M.C.C. and Soares | Distribuição espacial da resistência do solo à penetração e teor de água do solo em uma área de agrofloresta na região de Humaitá, AM [BibTeX] |
2014 | Comunicata Scientiae Vol. 5, pp. 509-517 |
article | |
BibTeX:
@article{campos_distribuicao_2014, author = {Campos, M. D. R. ; Aquino, R. E. ; Santos, L. A. C. ; Mantovanelli, B. C. ., M. C. C. ; Soares}, title = {Distribuição espacial da resistência do solo à penetração e teor de água do solo em uma área de agrofloresta na região de Humaitá, AM}, journal = {Comunicata Scientiae}, year = {2014}, volume = {5}, pages = {509--517} } |
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Campos, M., Santos, L.A.C., Oliveira, I.A., Aquino, R.E., Bergamin A.C., M.C.C. and Soares | Variabilidade espacial dos atributos físicos em um Argissolo Vermelho sob floresta [BibTeX] |
2013 | Comunicata Scientiae Vol. 4, pp. 168-178 |
article | |
BibTeX:
@article{campos_variabilidade_2013, author = {Campos, M.D.R. ; Santos, L. A. C. ; Oliveira, I. A. ; Aquino, R. E. ; Bergamin, A.C., M. C. C. ; Soares}, title = {Variabilidade espacial dos atributos físicos em um Argissolo Vermelho sob floresta}, journal = {Comunicata Scientiae}, year = {2013}, volume = {4}, pages = {168--178} } |
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Campos, M.R., Souza Júnior, V.S., Ribeiro Filho, M.R., Aquino, R.E., Oliveira I. A, M.C.C. and Ribeiro | Superfícies Geomórficas e Atributos do Solo em uma Toposseqüência de Transição Várzea-Terra Firme [BibTeX] |
2013 | Bioscience Journal Vol. 29, pp. 132-142 |
article | |
BibTeX:
@article{campos_superficies_2013, author = {Campos, Mateus Rosas ; Souza Júnior, V. S. ; Ribeiro Filho, M. R. ; Aquino, R. E. ; Oliveira, I. A, M. C. C. ; Ribeiro}, title = {Superfícies Geomórficas e Atributos do Solo em uma Toposseqüência de Transição Várzea-Terra Firme}, journal = {Bioscience Journal}, year = {2013}, volume = {29}, pages = {132--142} } |
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Campos, M., Souza Júnior, V., Almeida M.C., M. and Ribeiro | Relações solo-superfície geomórfica em uma topossequência várzea-terra firme na região de Humaitá (AM). [BibTeX] |
2012 | Revista Brasileira de Ciência do Solo Vol. 36, pp. 325-336 |
article | |
BibTeX:
@article{campos_relacoes_2012, author = {Campos, M.R.; Souza Júnior, V.S.; Almeida, M.C., M.C.C.; Ribeiro}, title = {Relações solo-superfície geomórfica em uma topossequência várzea-terra firme na região de Humaitá (AM).}, journal = {Revista Brasileira de Ciência do Solo}, year = {2012}, volume = {36}, pages = {325--336} } |
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Campos, M., Ribeiro, M.R., Souza Júnior, V.S.d., Ribeiro Filho, M.R. and Almeida, M.C. | Topossequência de solos na transição campos naturais-floresta na região de Humaitá, Amazonas [BibTeX] |
2012 | Acta Amazonica Vol. 42, pp. 387-398 |
article | |
BibTeX:
@article{campos_topossequencia_2012, author = {Campos, M.C.C. and Ribeiro, Mateus Rosas and Souza Júnior, Valdomiro Severino de and Ribeiro Filho, Mateus Rosas and Almeida, Maria Conceição}, title = {Topossequência de solos na transição campos naturais-floresta na região de Humaitá, Amazonas}, journal = {Acta Amazonica}, year = {2012}, volume = {42}, pages = {387--398} } |
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Campos, M. | Caracterização e gênese de solos em diferentes ambientes fisiográficos na região Sul do Amazonas. [BibTeX] |
2012 | Vol. 1 |
book | |
BibTeX:
@book{ed_caracterizacao_2012, author = {Campos, M.C.C.}, title = {Caracterização e gênese de solos em diferentes ambientes fisiográficos na região Sul do Amazonas.}, publisher = {PUC-Goiás}, year = {2012}, volume = {1}, note = {Section: 110p} } |
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Campos, J.G., Acevedo, O.C., Tota, J. and Manzi, A.O. | On the temporal scale of the turbulent exchange of carbon dioxide and energy above a tropical rain forest in Amazonia | 2009 | Journal of Geophysical Research-Atmospheres Vol. 114 |
article | DOI URL |
Abstract: The Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project has been using the eddy covariance technique since 1998 to monitor energy, water, and carbon surface fluxes over Amazonia. The results obtained up-to-date indicate high level of uncertainties, especially regarding the role of the Amazonian ecosystem to the global carbon budget. Besides the problems related to the eddy covariance measuring system (systematic error and nighttime stable conditions), an extremely important factor is associated with the averaging time scale or "time window'' used by the scientific community to determine the surface fluxes. This work presents initial efforts to determine the turbulence time scale for long-term carbon and energy surface fluxes over the Amazon rain forest. A total of 198 nights and 218 days during 2006 were analyzed. The multiresolution decomposition technique was applied to project the signal into several time scales and determine when the spectral and cospectral gap occurred. This technique permitted evaluating and separating the real contribution from turbulent and mesoscale fluxes to the total surface fluxes at both diurnal and nocturnal periods. The average turbulence time scale was below 200 and 1200 s for all scalars at nighttime and daytime, respectively. In all cases, there is seasonal dependence. This result shows that the time scale commonly used to calculate nocturnal surface fluxes (30 min) includes a good portion of mesoscale flux in the estimates. The role of these mesoscale fluxes, in terms of seasonal dependence and the uncertainties they add to the estimates, is then analyzed. | |||||
BibTeX:
@article{campos_temporal_2009, author = {Campos, Jose Galucio and Acevedo, Otavio C. and Tota, Julio and Manzi, Antonio O.}, title = {On the temporal scale of the turbulent exchange of carbon dioxide and energy above a tropical rain forest in Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2009}, volume = {114}, url = {://WOS:000265667300007 http://www.agu.org/journals/jd/jd0908/2008JD011240/2008JD011240.pdf}, doi = {https://doi.org/10.1029/2008jd011240} } |
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Campos, J.G. and Acevedo, O.C. | Revisitando a escala temporal da turbulência para escoamentos acima da Copa: caso noturna, sítio K-34 [BibTeX] |
2007 | Revista Ciência e Natura Vol. 12/07, pp. 105-108 |
article | |
BibTeX:
@article{campos_revisitando_2007, author = {Campos, J. G. and Acevedo, O. C.}, title = {Revisitando a escala temporal da turbulência para escoamentos acima da Copa: caso noturna, sítio K-34}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {12/07}, pages = {105--108} } |
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Campos, I.D., Mercier, F., Maheu, C., Cochonneau, G., Kosuth, P., Blitzkow, D. and Cazenave, A. | Temporal variations of river basin waters from Topex/Poseidon satellite altimetry. Application to the Amazon basin | 2001 | Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule a-Sciences De La Terre Et Des Planetes Vol. 333(10), pp. 633-643 |
article | URL |
Abstract: Although developed and optimised for open oceans, satellite altimetry has the potential to monitor level variations of inland surface waters such as lakes and rivers. Here we present results of water level variations of the Amazon River based on eight years (1993-2000) of altimetry data of the Topex/Poseidon satellite. We first discuss methods to detect wet surfaces from the altimetric measurements, discriminate between water and dry land, and quantify the accuracy of altimetric measurements over water. Then we show water level fluctuations at selected locations where the satellite crosses the Amazon River. The dominant signal is seasonal, mostly annual, with an amplitude of up to 10-15 m peak to peak. Comparison with in situ measurements indicates that water levels are well measured by Topex/Poseidon during high-water season, unlike low-water season, which suffers from data gaps. We further discuss the interannual component of the signal, which shows two marked minima in 1995 and 1998. The 1998 minimum is interpreted as an effect of the 1997-1998 ENSO event, causing rainfall deficit in the central part of the Amazon basin, hence decrease in wafer levels. An EOF analysis of precipitation fields over the basin during the 1993-1999 period confirms the rainfall minimum by the end of 1997 for this region. (C) 2001 Academie des sciences / Editions scientifiques et medicales Elsevier SAS. | |||||
BibTeX:
@article{campos_temporal_2001, author = {Campos, I. D. and Mercier, F. and Maheu, C. and Cochonneau, G. and Kosuth, P. and Blitzkow, D. and Cazenave, A.}, title = {Temporal variations of river basin waters from Topex/Poseidon satellite altimetry. Application to the Amazon basin}, journal = {Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule a-Sciences De La Terre Et Des Planetes}, year = {2001}, volume = {333}, number = {10}, pages = {633--643}, url = {://WOS:000172843400005} } |
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Camponogara Silva Dias, M.A.F.and.C.G.G.G. | Relationship between Amazon biomass burning aerosols and rainfall over the La Plata Basin [BibTeX] |
2014 | Atmospheric Chemistry and Physics Vol. 14(9), pp. 4397-4407 |
article | |
BibTeX:
@article{camponogara_relationship_2014, author = {Camponogara, Silva Dias, M. A. F. and Carrió, G. G., G.}, title = {Relationship between Amazon biomass burning aerosols and rainfall over the La Plata Basin}, journal = {Atmospheric Chemistry and Physics}, year = {2014}, volume = {14}, number = {9}, pages = {4397--4407} } |
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Campanharo, W., Lopes, A., Anderson, L., Da Silva, T. and Aragão, L. | Translating Fire Impacts in Southwestern Amazonia into Economic Costs [BibTeX] |
2019 | Remote Sensing Vol. 11, pp. 764 |
article | |
BibTeX:
@article{campanharo_translating_2019, author = {Campanharo, Wesley and Lopes, Aline and Anderson, Liana and Da Silva, Thiago and Aragão, Luiz}, title = {Translating Fire Impacts in Southwestern Amazonia into Economic Costs}, journal = {Remote Sensing}, year = {2019}, volume = {11}, pages = {764} } |
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Campanharo, A.S.L.O., Ramos, F.M., Macau, E.E.N., Rosa, R.R., Bolzan, M.J.A. and Sa, L.D.A. | Searching chaos and coherent structures in the atmospheric turbulence above the Amazon forest | 2008 | Philosophical Transactions of the Royal Society a-Mathematical Physical and Engineering Sciences Vol. 366(1865), pp. 579-589 |
article | DOI URL |
Abstract: In this work, the possible chaotic nature of the atmospheric turbulence above a densely forested area in the Amazon region is investigated. To this end, we use high- resolution temperature data obtained during a micrometeorological measurement campaign in the Brazilian Amazonia. Estimates of the correlation dimension (D-2=3.50 +/- 0.05) and of the largest Lyapunov exponent (lambda(1)=0.050 +/- 0.002) suggest the existence of chaos in the atmospheric boundary layer. Our findings indicate that this low- dimensional chaotic dynamics is associated with the presence of the coherent structures within the boundary layer right above the canopy top and not with the atmospheric turbulence per se, as previously claimed. | |||||
BibTeX:
@article{campanharo_searching_2008, author = {Campanharo, A. S. L. O. and Ramos, F. M. and Macau, E. E. N. and Rosa, R. R. and Bolzan, M. J. A. and Sa, L. D. A.}, title = {Searching chaos and coherent structures in the atmospheric turbulence above the Amazon forest}, journal = {Philosophical Transactions of the Royal Society a-Mathematical Physical and Engineering Sciences}, year = {2008}, volume = {366}, number = {1865}, pages = {579--589}, note = {Edition: 2007/08/19}, url = {://WOS:000252238700008 http://rsta.royalsocietypublishing.org/content/366/1865/579.full.pdf}, doi = {https://doi.org/10.1098/rsta.2007.2118} } |
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Camarinha-Neto, G.F., Cohen, J.C.P., Dias-Júnior, C.Q., Sörgel, M., Cattanio, J.H., Araújo, A., Wolff, S., Kuhn, P.A.F., Souza, R.A.F., Rizzo, L.V. and Artaxo, P. | The friagem event in the central Amazon and its influence on micrometeorological variables and atmospheric chemistry [BibTeX] |
2021 | Atmos. Chem. Phys. Vol. 21(1), pp. 339-356 |
article | DOI URL |
BibTeX:
@article{camarinha-neto_friagem_2021, author = {Camarinha-Neto, G. F. and Cohen, J. C. P. and Dias-Júnior, C. Q. and Sörgel, M. and Cattanio, J. H. and Araújo, A. and Wolff, S. and Kuhn, P. A. F. and Souza, R. A. F. and Rizzo, L. V. and Artaxo, P.}, title = {The friagem event in the central Amazon and its influence on micrometeorological variables and atmospheric chemistry}, journal = {Atmos. Chem. Phys.}, year = {2021}, volume = {21}, number = {1}, pages = {339--356}, url = {https://acp.copernicus.org/articles/21/339/2021/}, doi = {https://doi.org/10.5194/acp-21-339-2021} } |
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Camargo, P.B., Trumbore, S.E., Martinelli, L.A., Davidson, E.A., Nepstad, D.C. and Victoria, R.L. | Soil carbon dynamics in regrowing forest of eastern Amazonia | 1999 | Global Change Biology Vol. 5(6), pp. 693-702 |
article | DOI URL |
Abstract: The future flora of Amazonia will include significant areas of secondary forest as degraded pastures are abandoned and secondary succession proceeds. The rate at which secondary forests regain carbon (C) stocks and re-establish biogeochemical cycles that resemble those of primary forests will influence the biogeochemistry of the region. Most studies have focused on the effects of deforestation on biogeochemical cycles. In this study, we present data on the recuperation of carbon stocks and carbon fluxes within a secondary forest of the eastern Amazon, and we compare these measurements to those for primary forest, degraded pasture, and productive pasture. Along a transect from a 23-y-old degraded pasture, through a 7-y-old secondary forest, through a 16-year-old secondary forest, and to a primary forest, the delta(13)C values of soil organic matter (SOM) in the top 10 cm of soil were -21.0, -26.5, -27.4, and -27.9 parts per thousand, respectively, indicating that the isotopic signature of SOM from C3 forest plants was rapidly re-established. The degraded pasture also had significant inputs of C from C3 plants. Radiocarbon data indicated that most of the C in the top 10 cm of soil had been fixed by plants during the last 30 years. Differences in soil C inventory among land use types were small compared to uncertainties in their measurement. Root inputs were nearly identical in primary and secondary forests, and litterfall in the secondary forest was 88% of the litterfall rate of the primary forest. In contrast, the secondary forest had only 17% of the above ground biomass. Because of rapid cycling rates of soil C and rapid recovery of C fluxes to and from the soil, the below ground C cycle in this secondary forest was nearly identical with those of the unaltered primary forest. | |||||
BibTeX:
@article{camargo_soil_1999, author = {Camargo, P. B. and Trumbore, S. E. and Martinelli, L. A. and Davidson, E. A. and Nepstad, D. C. and Victoria, R. L.}, title = {Soil carbon dynamics in regrowing forest of eastern Amazonia}, journal = {Global Change Biology}, year = {1999}, volume = {5}, number = {6}, pages = {693--702}, url = {://WOS:000081655000007 http://onlinelibrary.wiley.com/store/10.1046/j.1365-2486.1999.00259.x/asset/j.1365-2486.1999.00259.x.pdf?v=1&t=h6hye7rk&s=e3006c73daaf413c36ea473f85f9de89538a7647}, doi = {https://doi.org/10.1046/j.1365-2486.1999.00259.x} } |
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Camara, G., Paula, A., Aguiar, D., Escada, M.I., Amaral, S., Carneiro, T., Monteiro, A.M.V., Araujo, R., Vieira, I. and Becker, B. | Amazonian deforestation models [BibTeX] |
2005 | Science Vol. 307(5712), pp. 1043-1044 |
article | DOI URL |
BibTeX:
@article{camara_amazonian_2005, author = {Camara, G. and Paula, A. and Aguiar, D. and Escada, M. I. and Amaral, S. and Carneiro, T. and Monteiro, A. M. V. and Araujo, R. and Vieira, I. and Becker, B.}, title = {Amazonian deforestation models}, journal = {Science}, year = {2005}, volume = {307}, number = {5712}, pages = {1043--1044}, note = {Edition: 2005/02/19}, url = {://WOS:000227197300020}, doi = {https://doi.org/10.1126/science.307.5712.1043c} } |
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Callede, J., Kosuth, P., Guyot, J.L. and Guimaraes, V.S. | Discharge determination by Acoustic Doppler Current Profilers (ADCP): a moving bottom error correction method and its application on the River Amazon at Obidos | 2000 | Hydrological Sciences Journal-Journal Des Sciences Hydrologiques Vol. 45(6), pp. 911-924 |
article | DOI URL |
Abstract: Since 1995, hydrologists of the HiBAm (Hydrology and Geochemistry of the Amazon Basin) Research Program carried out several hundred discharge measurements in the Amazon basin. Implementation of modern discharge measurement techniques using ultrasonic devices (ADCP), give evidence of a systematic error linked to the displacement of the river bottom due to high water velocity close to the bottom. This error leads to an underestimation of discharge value. It was possible to establish a correlation between the water velocity close to the river bottom and the error between real position and position computed by ADCP when the boat returns to its starting point after a two-way crossing of the river. When there is no bottom displacement, i.e. during low flow period, this return position error is weak (less than 50 m). This has allowed quantification of river bed load speed, or bottom displacement speed. A correction method was developed on the basis of this correlation. This method, systematically applied to ADCP discharge measurements obtained at Obidos hydrometric station, allowed all measured discharges to be corrected, especially for 1997 and 1999 floods. Another method, based on the analysis of rear trajectory of the boat (obtained from topographic measurement or GPS positioning) compared with the ADCP computed trajectory, is under study. | |||||
BibTeX:
@article{callede_discharge_2000, author = {Callede, J. and Kosuth, P. and Guyot, J. L. and Guimaraes, V. S.}, title = {Discharge determination by Acoustic Doppler Current Profilers (ADCP): a moving bottom error correction method and its application on the River Amazon at Obidos}, journal = {Hydrological Sciences Journal-Journal Des Sciences Hydrologiques}, year = {2000}, volume = {45}, number = {6}, pages = {911--924}, url = {://WOS:000165704700008}, doi = {https://doi.org/10.1080/02626660009492392} } |
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Callede, J., Kosuth, P. and De Oliveira, E. | Establishment of the stage-discharge relationship of the River Amazon at Obidos: "normaI difference in level" method using "variable geometry" | 2001 | Hydrological Sciences Journal-Journal Des Sciences Hydrologiques Vol. 46(3), pp. 451-463 |
article | DOI URL |
Abstract: This paper describes the way in which the daily discharges of the River Amazon were calculated at Obidos. The stage-discharge relationship is practically univocal in low and mean water. In high flow periods, the scatter of the stream gaugings compared to the univocal rating curve effects the correction of the discharges according to the levels at Santarem then at Parintins. The "normal difference in level" method is not well adapted for Obidos: it was replaced by a "normal difference in level with variable geometry" method, a function of the water levels at Obidos. While using only the Santarem station, the application of this new method reduced the scattering to 3.0% on the entire rating curve. | |||||
BibTeX:
@article{callede_establishment_2001, author = {Callede, J. and Kosuth, P. and De Oliveira, E.}, title = {Establishment of the stage-discharge relationship of the River Amazon at Obidos: "normaI difference in level" method using "variable geometry"}, journal = {Hydrological Sciences Journal-Journal Des Sciences Hydrologiques}, year = {2001}, volume = {46}, number = {3}, pages = {451--463}, url = {://WOS:000169275500009}, doi = {https://doi.org/10.1080/02626660109492838} } |
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Callede, J., Guyot, J.L., Ronchail, J., Molinier, M. and De Oliveira, E. | The River Amazon at Obidos (Brazil): Statistical studies of the discharges and water balance | 2002 | Hydrological Sciences Journal-Journal Des Sciences Hydrologiques Vol. 47(2), pp. 321-333 |
article | DOI URL |
Abstract: New discharge measurements carried out within the "Hidrologia e geoquimica na Bacia Amazonica" (HiBAm) Project at Obidos have improved the knowledge about the hydrological characteristics of the Amazon at this station, which controls the highest discharges in the world. A new correction method determines the daily discharge with an accuracy of +/-3.0%. The reconstruction of the missing data, using observations from Manaus, makes it possible to build a chronology for almost one century. With this sample starting in 1902, the interannual average discharge of the Amazon at Obidos is 163 000 m(3) s(-1), with an extremely weak irregularity coefficient (K3 = 1.28). The decennial low water (78 000 m(3) s(-1)) is similar to the centenary flood of the River Congo at Brazzaville. The decennial flood is estimated to be 260 000 m(3) s(-1). Water balance studies indicate an outflow deficit of 1193 mm, which can be identified with actual evapotranspiration. In conclusion, the Amazon is confirmed to be the most powerful and regular river of the planet. | |||||
BibTeX:
@article{callede_river_2002, author = {Callede, J. and Guyot, J. L. and Ronchail, J. and Molinier, M. and De Oliveira, E.}, title = {The River Amazon at Obidos (Brazil): Statistical studies of the discharges and water balance}, journal = {Hydrological Sciences Journal-Journal Des Sciences Hydrologiques}, year = {2002}, volume = {47}, number = {2}, pages = {321--333}, url = {://WOS:000175177500012}, doi = {https://doi.org/10.1080/02626660209492933} } |
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Callede, J., Guyot, J.L., Ronchail, J., L'Hote, Y., Niel, H. and De Oliveira, E. | Evolution of the River Amazon's discharge at Obidos from 1903 to 1999 | 2004 | Hydrological Sciences Journal-Journal Des Sciences Hydrologiques Vol. 49(1), pp. 85-97 |
article | DOI URL |
Abstract: The time series of 97 annual values, observed or reconstituted, of runoff of the River Amazon at Obidos shows a slight increase of 9% in the mean annual discharges from 1903 to 1999, and of 10% for the floods. All the rupture tests indicate a break in 1970, for the mean annual discharges as well as for the floods. The evolution of the coefficients of variation indicates a reduction in the interannual variability of the mean discharges and floods, from 1927 to 1970. The comparison between the evolution of the mean annual discharges and the average annual rainfall of the basin, from 1945 to 1998, exhibits a good correlation between precipitation and runoff. Finally, the analysis of the evolution of the mean annual discharge and the average annual rainfall, expressed as a percentage of the deviation from the 19451998 averages, demonstrates an increase in the flow in relation to the rainfall, which could be the consequence of the Amazonian deforestation. | |||||
BibTeX:
@article{callede_evolution_2004, author = {Callede, J. and Guyot, J. L. and Ronchail, J. and L'Hote, Y. and Niel, H. and De Oliveira, E.}, title = {Evolution of the River Amazon's discharge at Obidos from 1903 to 1999}, journal = {Hydrological Sciences Journal-Journal Des Sciences Hydrologiques}, year = {2004}, volume = {49}, number = {1}, pages = {85--97}, url = {://WOS:000188756300007}, doi = {https://doi.org/10.1623/hysj.49.1.85.53992} } |
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Caldas, M., Walker, R., Arima, E., Perz, S., Aldrich, S. and Simmons, C. | Theorizing land cover and land use change: The peasant economy of Amazonian deforestation | 2007 | Annals of the Association of American Geographers Vol. 97(1), pp. 86-110 |
article | DOI URL |
Abstract: This article addresses deforestation processes in the Amazon basin, using regression analysis to assess the impact of household structure and economic circumstances on land use decisions made by colonist farmers in the forest frontiers of Brazil. Unlike many previous regression-based studies, the methodology implemented analyzes behavior at the level of the individual property, using both survey data and information derived from the classification of remotely sensed imagery. The regressions correct for endogenous relationships between key variables and spatial autocorrelation, as necessary. Variables used in the analysis are specified, in part, by a theoretical development integrating the Chayanovian concept of the peasant household with spatial considerations stemming from von Thunen. Results from the empirical model indicate that demographic characteristics of households, as well as market factors, affect deforestation in the Amazon basin associated with colonists. Therefore, statistical results from studies that do not include household-scale information may be subject to error. From a policy perspective, the results suggest that environmental policies in the Amazon based on market incentives to small farmers may not be as effective as hoped, given the importance of household factors in catalyzing the demand for land. The article concludes by noting that household decisions regarding land use and deforestation are not independent of broader social circumstances, and that a full understanding of Amazonian deforestation will require insight into why poor families find it necessary to settle the frontier in the first place. | |||||
BibTeX:
@article{caldas_theorizing_2007, author = {Caldas, Marcellus and Walker, Robert and Arima, Eugenio and Perz, Stephen and Aldrich, Stephen and Simmons, Cynthia}, title = {Theorizing land cover and land use change: The peasant economy of Amazonian deforestation}, journal = {Annals of the Association of American Geographers}, year = {2007}, volume = {97}, number = {1}, pages = {86--110}, url = {://WOS:000244775700006}, doi = {https://doi.org/10.1111/j.1467-8306.2007.00525.x} } |
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Butt, N., New, M., Malhi, Y., Lola da Costa, A.C., Oliveira, P. and Eduardo Silva-Espejo, J. | Diffuse radiation and cloud fraction relationships in two contrasting Amazonian rainforest sites | 2010 | Agricultural and Forest Meteorology Vol. 150(3), pp. 361-368 |
article | DOI URL |
Abstract: Along with total radiation received, the proportion of diffuse to direct solar radiation can influence forest photosynthesis and carbon cycling. However, tropical diffuse radiation regimes are poorly described, and to date there are few or no site-based or regional diffuse radiation datasets. The relationship between cloud fraction and diffuse solar radiation was investigated using data from two sites in western and eastern Amazonia. Radiation regimes for diffuse and total radiation were characterised for each site, and the variation in clear sky diffuse radiation fraction between wet and dry season demonstrated and quantified, as well as the dependence of diffuse radiation on cloud amount. Using high frequency measurements of diffuse and total solar radiation data from the two sites, and estimated top of the canopy clear-sky radiation, a number of alternative models to predict diffuse radiation fraction from cloud fraction were formulated and tested. Results showed that cloud fraction can be approximated using the relationship between observed and calculated top of canopy radiation, after which diffuse radiation can then be predicted from cloud fraction. We also demonstrate that satellite cloud data (from the International Satellite Cloud Climatology Project) can be used as inputs to the diffuse radiation model to provide estimates of annual and monthly diffuse radiation proportion. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{butt_diffuse_2010, author = {Butt, Nathalie and New, Mark and Malhi, Yadvinder and Lola da Costa, Antonio Carlos and Oliveira, Paulo and Eduardo Silva-Espejo, Javier}, title = {Diffuse radiation and cloud fraction relationships in two contrasting Amazonian rainforest sites}, journal = {Agricultural and Forest Meteorology}, year = {2010}, volume = {150}, number = {3}, pages = {361--368}, url = {://WOS:000276122500005}, doi = {https://doi.org/10.1016/j.agrformet.2009.12.004} } |
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Butt, N., New, M., Lizcano, G. and Malhi, Y. | Spatial patterns and recent trends in cloud fraction and cloud-related diffuse radiation in Amazonia | 2009 | Journal of Geophysical Research-Atmospheres Vol. 114 |
article | DOI URL |
Abstract: As the climate of tropical forest regions changes, there are likely to be concurrent changes in cloud cover and in the light regime experienced by tropical forest canopies. We utilize data from the International Satellite Cloud Climatology Project to examine spatial patterns and trends in cloud cover over Amazonia during the period 1984-2006. Cloud cover seasonality appears to be increasing in Amazonia, with a significant decline in dry season cloud fraction (0.3% yr(-1)) and increase in wet season cloud fraction (0.1% yr(-1)) over the last two decades. A novel cloud-related diffuse radiation (CRDR) climatology for Amazonia was derived from satellite cloud data. There is a clear decreasing gradient from the northwest to the southeast: annual CRDR proportion (CRDRP) varies by about 15% across the region. Analysis of trends over time indicates a 1-2% decline in CRDRP in Amazonia over the last two decades, particularly in the east of the region. This is particularly marked in the dry season in the east where CRDRP declined at a rate of 0.3% yr(-1), and the wet season decline was 0.1% yr(-1). In the west of the region a 1% increase in CRDRP is indicated. Changes in forest composition and productivity may be linked to changes in CRDRP in that decreases in cloud cover in sunny regions or dry seasons may cause a decline in productivity, whereas declines in cloud cover in cloudy regions, or during cloudy seasons, may cause an increase in productivity. | |||||
BibTeX:
@article{butt_spatial_2009, author = {Butt, Nathalie and New, Mark and Lizcano, Gil and Malhi, Yadvinder}, title = {Spatial patterns and recent trends in cloud fraction and cloud-related diffuse radiation in Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2009}, volume = {114}, url = {://WOS:000271850100002 http://www.agu.org/journals/jd/jd0921/2009JD012217/2009JD012217.pdf}, doi = {https://doi.org/10.1029/2009jd012217} } |
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Butt, N., Malhi, Y., Phillips, O. and New, M. | Floristic and functional affiliations of woody plants with climate in western Amazonia | 2008 | Journal of Biogeography Vol. 35(5), pp. 939-950 |
article | DOI URL |
Abstract: Aim To test whether a direct relationship exists between the relative abundance of woody plant genera and precipitation regime along the north-south climate gradient of the western Amazon. Location Lowland rain forests in the western Amazon. Methods Floristic data on 91 woody plant genera, from 39 0.1-ha plots across the western Amazon, and precipitation data from a 0.5 degrees global data set were used to test for correlations between plant relative abundance (defined as percentage number of stems textgreater= 2.5 cm diameter at breast height for each woody plant genus per plot) and derived dry-season variables. Moisture preference was then assessed in terms of pioneer and shade-tolerant life-history strategy. Results There were significant associations between the distribution of plant relative abundances and seasonal precipitation variables in 34% of genera analysed. Significant differences were identified in size-class distribution between dry affiliates and generalists. Dry affiliates were not dominant in any size class in any plot type, whereas climate generalists dominated most of the size classes in the dry plots and the mid-range size classes in the wet plots. Dry-affiliate genera were a minority, even in dry forests. Wet-affiliate genera were correlated with shade tolerance, whereas genera with no rainfall affiliation were often pioneers. Main conclusions The results suggest that moisture variable seasonality influences community composition in a manner that can be related to the life-history trade-off between shade tolerance and pioneer ranking. One possible reason for higher diversity in wetter forests is that high rainfall amplifies the niche space available to shade-tolerant plants. Determining which plant groups are constrained by which environmental variables can contribute to our understanding of how forest composition may be changing now, and how it may change under future climate: if shade-tolerant trees are also drought-intolerant, community structure in wet forests may be more vulnerable to future increases in moisture stress. | |||||
BibTeX:
@article{butt_floristic_2008, author = {Butt, Nathalie and Malhi, Yadvinder and Phillips, Oliver and New, Mark}, title = {Floristic and functional affiliations of woody plants with climate in western Amazonia}, journal = {Journal of Biogeography}, year = {2008}, volume = {35}, number = {5}, pages = {939--950}, url = {://WOS:000254990500016 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2699.2007.01878.x/asset/j.1365-2699.2007.01878.x.pdf?v=1&t=h6hxuzgw&s=27f37572d64ab57310a8b103e30781c47e1cacf3}, doi = {https://doi.org/10.1111/j.1365-2699.2007.01878.x} } |
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Butt, N., Malhi, Y., New, M., Macía, M.J., Lewis, S.L., Lopez-Gonzalez, G., Laurance, W.F., Laurance, S., Luizão, R., Andrade, A., Baker, T.R., Almeida, S. and Phillips, O.L. | Shifting dynamics of climate-functional groups in old-growth Amazonian forests [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 267-279 |
article | |
BibTeX:
@article{butt_shifting_2014, author = {Butt, Nathalie and Malhi, Yadvinder and New, Mark and Macía, Manuel J. and Lewis, Simon L. and Lopez-Gonzalez, Gabriela and Laurance, William F. and Laurance, Susan and Luizão, Regina and Andrade, Ana and Baker, Timothy R. and Almeida, Samuel and Phillips, Oliver L.}, title = {Shifting dynamics of climate-functional groups in old-growth Amazonian forests}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {267--279} } |
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Butt, N., de Oliveira, P.A. and Costa, M.H. | Evidence that deforestation affects the onset of the rainy season in Rondonia, Brazil | 2011 | Journal of Geophysical Research-Atmospheres Vol. 116 |
article | DOI URL |
Abstract: Anecdotes from local residents and modeling studies suggest that deforestation may delay the onset of the rainy season (O) in western Brazil, but detection studies using climatological time series are not available. Here we investigate trends in O in the state of Rondonia, Brazil, a region that has been continuously deforested since the 1970s. Daily rainfall data from 16 station time series, spanning periods of at least 25 years, with five covering more than 30 years, are used. We define O as the first day after 1 September with rainfall greater than 20 mm d(-1). A t test indicates that for stations that lie inside the major deforested area, O has significantly shifted to, on average, 11 days (and up to 18 days) later in the year over the last three decades. However, for stations that lie in areas that have not been heavily deforested, O has not shifted significantly. Nonparametric and parametric trend analyses all gave similar results for the change of O with time, and all of the statistically significant results indicated a delay in O. Twenty-five percent (four) of the stations analyzed showed a marked shift in timing of O: these stations are located inside deforested areas, primarily near the BR 364 highway that crosses Rondonia. Delayed onset may be a result of land use change, and this signal may strengthen in future: current delaying trends may be as great as 0.6 days per year, and after 30 years of deforestation the onset of the rainy season is expected to be 18 days later. | |||||
BibTeX:
@article{butt_evidence_2011, author = {Butt, Nathalie and de Oliveira, Paula Afonso and Costa, Marcos Heil}, title = {Evidence that deforestation affects the onset of the rainy season in Rondonia, Brazil}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2011}, volume = {116}, url = {://WOS:000291821400001 http://www.agu.org/journals/jd/jd1111/2010JD015174/2010JD015174.pdf}, doi = {https://doi.org/10.1029/2010jd015174} } |
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Bustillo, V., Victoria, R.L., Sousa de Moura, J.M., Victoria, D.d.C., Andrade Toledo, A.M. and Collicchio, E. | Factors driving the biogeochemical budget of the Amazon River and its statistical modelling | 2011 | Comptes Rendus Geoscience Vol. 343(4), pp. 261-277 |
article | DOI URL |
Abstract: The seasonal and interannual fluctuations of the biogeochemical budget (solutes, suspended matter, isotopes) of the Amazon River basin were analyzed, with a special focus on 44 physicochemical parameters monitored over the period 1982-1984 during the Carbon in the AMazon River Experiment (CAMREX) project. The relevant factors driving this variability were identified and sorted through the implementation of a statistical-regressive model coupled to variance analysis. Basically, the compositional fluctuations in the Amazon River are related (1) to the variable contribution of major tributaries (variable regional source) to the river flow but also (2) to the variable contribution of hydrological sources, (3) to river processes, i.e. in-stream diagenesis and sediment dynamics and (4) to the hydrological budget of the floodplains. Their respective contributions to the variability of chemical signals observed in the stream waters depend on which parameter was investigated but their combination explains on average 85% of the observed variability. The variability related to regional sources was captured by the compared measures of flow discharge and biogeochemical fluxes at the outlet of the major tributaries. The variability of hydrological sources was described by the variable contribution of three runoffs of distinct but constant composition: forwarded direct runoff, delayed floodplain runoff and baseflow. Several methods were tested to depict the seasonal and interannual variations of their individual discharges. Biologically-mediated processes were related to a hydrobiological index I(BIO) = [O(2)]-[CO(2)] which allows tracking the nature of the dominant ecological regime (autotrophy vs. heterotrophy). The alteration of chemical signals related to the intermittent discharge of the floodplains (where specific processes occur such as: gas exchanges at the air-water interface, sorption of dissolved organic matter, chemical weathering, deposition vs. remobilization of sediments, etc.) was simulated by taking into account the default of hydrological balance between inflows and outflows, used as a marker of floodplains discharge. This analysis shows that the chemical baseline observed in the waters of the Amazon River is mostly acquired upstream from the junction of major tributaries with the Amazon main reach. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved. | |||||
BibTeX:
@article{bustillo_factors_2011, author = {Bustillo, Vincent and Victoria, Reynaldo Luiz and Sousa de Moura, Jose Mauro and Victoria, Daniel de Castro and Andrade Toledo, Andre Marcondes and Collicchio, Erich}, title = {Factors driving the biogeochemical budget of the Amazon River and its statistical modelling}, journal = {Comptes Rendus Geoscience}, year = {2011}, volume = {343}, number = {4}, pages = {261--277}, url = {://WOS:000290368900001}, doi = {https://doi.org/10.1016/j.crte.2011.01.003} } |
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Bustillo, V., Victoria, R.L., Sousa de Moura, J.M., Victoria, D.d.C., Andrade Toledo, A.M. and Collicchio, E. | Biogeochemistry of the Amazonian Floodplains: Insights from Six End-Member Mixing Models | 2010 | Earth Interactions Vol. 14 |
article | DOI URL |
Abstract: The influence of Amazonian floodplains on the hydrological, sedimentary, and biogeochemical river budget was investigated along the Vargem Grande-Obidos reach, by applying six mixing models based on variable regional and/or variable hydrological sources. By comparing the output of many different models designed for different purposes, the nature and the magnitude of processes linking water and biogeochemical budgets of the Amazonian floodplains were clarified. This study reveals that most of the chemical baseline of the Amazon River basin is acquired before the studied 2000-km Amazonian reach. However, the tight connection between the hydrograph stage of the river and the chemical signals provides insightful information on the dynamics of its floodplains. The chemical expression of biotic and abiotic processes occurring in the Amazonian floodplains can be particularly perceived during falling waters. It appears delayed in time compared to the maximum extension of submerged area, because the alternating water circulation polarity (filling versus emptying) between the main channel and the adjacent floodplains determines delayed emptying of floodplains during falling waters. It results also in a longer time of residence in the hydrograph network, which strengthens the rate of transformation of transiting materials and solutes. Biotic and biologically mediated processes tend to accentuate changes in river water chemistry initiated upstream, in each sub-basin, along river corridors, indicating that processes operating downstream prolong those from upstream(e.g., floodplains of the large tributaries). Conversely, the flood wave propagation tends to lessen the seasonal variability as a result of the water storage in the floodplains, which admixes waters of distinct origins (in time and space). The morphology of floodplains, determining the deposition and the diagenesis of the sediments as well as the variable extension of submerged areas or the chronology of floodplains storage/emptying, appears to be the main factor controlling the floodplains biogeodynamics. By coupling classical end-member mixing models (providing insight on hydrological source) with a variable regional contribution scheme, relevant information on the biogeochemical budget of the Amazonian floodplains can be achieved. | |||||
BibTeX:
@article{bustillo_biogeochemistry_2010, author = {Bustillo, Vincent and Victoria, Reynaldo Luiz and Sousa de Moura, Jose Mauro and Victoria, Daniel de Castro and Andrade Toledo, Andre Marcondes and Collicchio, Erich}, title = {Biogeochemistry of the Amazonian Floodplains: Insights from Six End-Member Mixing Models}, journal = {Earth Interactions}, year = {2010}, volume = {14}, url = {://WOS:000282360500001}, doi = {https://doi.org/10.1175/2010EI326.s1} } |
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Bustillo, V., Victoria, R.L., Sousa de Moura, J.M., Victoria, D.d.C., Andrade Toledo, A.M. and Colicchio, E. | Biogeochemistry of Carbon in the Amazonian Floodplains over a 2000-km Reach: Insights from a Process-Based Model | 2011 | Earth Interactions Vol. 15 |
article | DOI URL |
Abstract: The influence of Amazonian floodplains on the hydrological, sedimentary, and biogeochemical river budget was investigated over a 2000-km reach. A process-based model relying on the closure of chemical fluxes and isotopic signals was implemented. On average for the whole studied reach, the overall fluxes of carbon associated with mineralization and aquatic photosynthesis were estimated to 35.7 and 15.3 Tg C yr(-1), respectively. Almost 57% of the carbon sequestrated by photosynthesis comes from aerial sources (flooded forest); the remaining 43% resulted from aquatic sources (varzea grasses and phytoplankton). The process rates substantially fluctuate over the annual cycle, depending particularly on the extension of flooded area and on the river-floodplain connectivity. As the river level declines, the drastic decrease of turbidity and the lower supply of carbon substrates promote autotrophy to the detriment of heterotrophy, leading to substantial changes of pH and gaseous equilibria in the river water. The main consequences are (i) the side-chain oxidation of dissolved organic matter leading to the concomitant rises of the carbon to nitrogen atomic ratio and nitrate contents and (ii) the sorption of hydrophobic humic acids, which fractionate (13)C and thus lead to (13)C-depleted particulate organic matter (fine fraction) compared to remaining dissolved organic matter. As the river flow rises, the heterotrophy prevails over autotrophy and this tends to attenuate the chemical signature imprinted by the latter. The significant contribution of aerial autochthonous sources to the budget of carbon indicates that the fluxes of mineralization are sustained by the net primary production of river corridors. The variable extension of submerged areas defines the proportions of CO(2) exported by the river and released to the atmosphere. The rate of CO(2) outgassing on the studied reach (18.8 Tg C yr(-1)) represents about 50% of the incoming dissolved inorganic carbon flux. The rate of methane emission is estimated as 2.2 Tg C yr(-1) and that of denitrification is estimated as 0.87 Tg N yr(-1), representing 1.5 times the flux of dissolved inorganic nitrogen (DIN) exported by the Amazon River at the station of Obidos (0.64 Tg N yr(-1)). | |||||
BibTeX:
@article{bustillo_biogeochemistry_2011, author = {Bustillo, Vincent and Victoria, Reynaldo Luiz and Sousa de Moura, Jose Mauro and Victoria, Daniel de Castro and Andrade Toledo, Andre Marcondes and Colicchio, Erich}, title = {Biogeochemistry of Carbon in the Amazonian Floodplains over a 2000-km Reach: Insights from a Process-Based Model}, journal = {Earth Interactions}, year = {2011}, volume = {15}, url = {://WOS:000291145600001 http://journals.ametsoc.org/doi/abs/10.1175/2010EI338.1}, doi = {https://doi.org/10.1175/2010ei338.1} } |
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Bustamante, M.M.C., Nobre, C.A., Smeraldi, R., Aguiar, A.P.D., Barioni, L.G., Ferreira, L.G., Longo, K., May, P., Pinto, A.S. and Ometto, J.P.H.B. | Estimating greenhouse gas emissions from cattle raising in Brazil [BibTeX] |
2012 | Climatic Change Vol. 115, pp. 559-577 |
article | DOI |
BibTeX:
@article{bustamante_estimating_2012, author = {Bustamante, Mercedes M. C. and Nobre, Carlos A. and Smeraldi, Roberto and Aguiar, Ana P. D. and Barioni, Luis G. and Ferreira, Laerte G. and Longo, Karla and May, Peter and Pinto, Alexandre S. and Ometto, Jean P. H. B.}, title = {Estimating greenhouse gas emissions from cattle raising in Brazil}, journal = {Climatic Change}, year = {2012}, volume = {115}, pages = {559--577}, doi = {https://doi.org/10.1007/s10584-012-0443-3} } |
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Bustamante, M.M.C., Medina, E., Asner, G.P., Nardoto, G.B. and Garcia-Montiel, D.C. | Nitrogen cycling in tropical and temperate savannas | 2006 | Biogeochemistry Vol. 79(1-2), pp. 209-237 |
article | DOI URL |
Abstract: Savannas are the most common vegetation type in the tropics and subtropics, ranging in physiognomy from grasslands with scattered woody plants to woodlands with heterogeneous grass cover. Productivity and organic matter turnover in savannas are controlled by interactions between water and nutrient availability, and this basic environmental structure is modified by fire frequency and land management practices. We compared temperate and tropical savannas in order to understand the strength of nitrogen (N) limitation of productivity. American tropical and temperate savannas are N limited systems, and the N cycle differs according to the woody plant density, fire frequency, land use change, N deposition and N fixation. Grazing and conversion to pasture have been the predominant land-use changes in most savannas. In the Cerrado and the Llanos tropical savannas, intensified use of fire for pasture management is leading to decreased woody plant density. Oppositely, in the Chaco and North American temperate savannas,. re suppression and grazing are leading to increases in woody density. In addition, the higher soil P availability in the Gran Chaco and the higher N deposition in North American savannas may be contributing to increases of N cycling and net productivity rates. Some aspects of the N budget for savannas of the American continent are still unclear and require further analysis to determine rates of N fixation, and to understand how spatial and temporal soil heterogeneity control N fluxes through soil solution and into streams. | |||||
BibTeX:
@article{bustamante_nitrogen_2006, author = {Bustamante, M. M. C. and Medina, E. and Asner, G. P. and Nardoto, G. B. and Garcia-Montiel, D. C.}, title = {Nitrogen cycling in tropical and temperate savannas}, journal = {Biogeochemistry}, year = {2006}, volume = {79}, number = {1-2}, pages = {209--237}, url = {://WOS:000240033100011 http://www.springerlink.com/content/w24n5h12847vj605/fulltext.pdf}, doi = {https://doi.org/10.1007/s10533-006-9006-x} } |
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Bustamante, M.M.C., Martinelli, L.A., Silva, D.A., Camargo, P.B., Klink, C.A., Domingues, T.F. and Santos, R.V. | (15)N natural abundance in woody plants and soils of central Brazilian savannas (cerrado) | 2004 | Ecological Applications Vol. 14(4), pp. S200-S213 |
article | URL |
Abstract: We measured the (15)N natural abundance values of 320 individuals belonging to 45 different plant species of the Brazilian cerrado. We also determined delta(15)N of soil nitrogen as a function of soil depth. Our purpose was to test the hypothesis that N-limited cerrado would have a large range of plant delta(15)N values, similar to patterns seen in northern high-latitude ecosystems. Foliar delta(15)N values did demonstrate the large range found in some other N-limited ecosystems, varying from -5parts per thousand to +7.9parts per thousand, Significant variability within individual species was also seen across cerrado community types. Several factors contributed to this variability, including the presence of N-fixing legumes, associations with mycorrhizal fungi, delta(15)N variability of soil organic matter with depth, fire events, and the seasonality of N-immobilization and mineralization processes in cerrado soils. | |||||
BibTeX:
@article{bustamante_15n_2004, author = {Bustamante, M. M. C. and Martinelli, L. A. and Silva, D. A. and Camargo, P. B. and Klink, C. A. and Domingues, T. F. and Santos, R. V.}, title = {(15)N natural abundance in woody plants and soils of central Brazilian savannas (cerrado)}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S200--S213}, url = {://WOS:000223269000017} } |
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Bustamante, M.M.C., Keller, M. and Silva, D.A. | Sources and Sinks of Trace Gases in Amazonia and the Cerrado [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 337-354 |
incollection | |
BibTeX:
@incollection{m_keller_sources_2009, author = {Bustamante, M. M. C. and Keller, M. and Silva, D. A.}, title = {Sources and Sinks of Trace Gases in Amazonia and the Cerrado}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {337--354} } |
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Bustamante I. Roitman, T.A.A.A.L.A.L.A.G.A.J.B.E.B.J.C.M.C.T.F.L.F.J.F.M.K.W.M.L.M.D.M.J.O.M.P.C.P.D.S.S.T.I.V.M. | Towards an integrated monitoring framework to assess the effects of tropical forest degradation and recovery on carbon stocks and biodiversity [BibTeX] |
2015 | Global Change Biology | article | DOI |
BibTeX:
@article{bustamante_towards_2015, author = {Bustamante, I. Roitman, T.M. Aide, A. Alencar, L. Anderson, L. Aragão, G.P. Asner, J. Barlow, E. Berenguer, J. Chambers, M.H. Costa, T. Fanin, L.G. Ferreira, J.N. Ferreira, M. Keller, W.E. Magnusson., L. Morales., D. Morton, J.P.H.B. Ometto, M. Palace, C. Peres, D. Silvério, S. Trumbore, I.C.G. Vieira, M.M.C.}, title = {Towards an integrated monitoring framework to assess the effects of tropical forest degradation and recovery on carbon stocks and biodiversity}, journal = {Global Change Biology}, year = {2015}, doi = {https://doi.org/10.1111/gcb.13087} } |
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Bustamante, M.C., Roitman, I., Aide, T., Alencar, A., Anderson, L.O.A., Asner, G., Barlow, J., Berenguer, E., CHambers, J., Costa, M., Fanin, T., Ferreira, L., Ferreira, J., Keller, M., Magnusson, W., Morales, L., Morton, D., Ometto, J., Palace, M., Peres, C., Silverio, D., Trumbore, S. and Vieira, I. | Toward an integrated monitoring framework to assess the effects of tropical forest degradation and recovery on carbon stocks and biodiversity [BibTeX] |
2015 | Global Change Biology Vol. 22, pp. 92-109 |
article | DOI |
BibTeX:
@article{bustamante_toward_2015, author = {Bustamante, M. C. and Roitman, I. and Aide, T.M. and Alencar, A. and Anderson, Liana O. Aragão and Asner, G. and Barlow, J. and Berenguer, E. and CHambers, J. and Costa, M. and Fanin, T. and Ferreira, L. and Ferreira, J. and Keller, M. and Magnusson, W. and Morales, L. and Morton, D. and Ometto, J. and Palace, M. and Peres, C. and Silverio, D. and Trumbore, S. and Vieira, I.}, title = {Toward an integrated monitoring framework to assess the effects of tropical forest degradation and recovery on carbon stocks and biodiversity}, journal = {Global Change Biology}, year = {2015}, volume = {22}, pages = {92--109}, doi = {https://doi.org/10.1111/gcb.13087} } |
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Buscardo, E., Souza, R.C., Meir, P., Geml, J., Schmidt, S.K., da Costa, A.C.L. and Nagy, L. | Effects of natural and experimental drought on soil fungi and biogeochemistry in an Amazon rain forest | 2021 | Communications Earth & Environment Vol. 2(1), pp. 55 |
article | DOI URL |
Abstract: Microbiota are essential components of the soil, driving biogeochemical cycles. Fungi affect decomposition and biotic interactions with plants across scales. Climate projections suggest that extended dry seasons may transform sensitive rain forests into savanna-like vegetation, with consequent changes in biogeochemistry. Here we compare the impacts of natural seasonality with 14 years of partial throughfall exclusion in an Amazonian rain forest, focussing on soil fungal functional diversity, extracellular soil enzyme activities (EEA) and their implications for nutrient dynamics. Large changes in fungal diversity and functional group composition occur in response to drought, with a conspicuous increase in the abundance of dark-septate fungi and a decrease in fungal pathogens. The high seasonality of EEA in the control (non droughted) and suppression of seasonality in the drought treatment, together with an increased implied nitrogen demand in the dry season induced by experimental drought, suggest that the changed soil microbiota activity may signal a pending shift in the biogeochemical functioning of the forest. | |||||
BibTeX:
@article{buscardo_effects_2021, author = {Buscardo, Erika and Souza, Rômulo C. and Meir, Patrick and Geml, József and Schmidt, Steven K. and da Costa, Antônio C. L. and Nagy, Laszlo}, title = {Effects of natural and experimental drought on soil fungi and biogeochemistry in an Amazon rain forest}, journal = {Communications Earth & Environment}, year = {2021}, volume = {2}, number = {1}, pages = {55}, url = {https://doi.org/10.1038/s43247-021-00124-8}, doi = {https://doi.org/10.1038/s43247-021-00124-8} } |
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Buscardo, E., Nardoto, G.B., Luizão, F., Piedade, M.T.F. and Schöngart, J. | The Biogeochemistry of the Main Forest Vegetation Types in Amazonia [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 225-266 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_biogeochemistry_2016, author = {Buscardo, E. and Nardoto, G. B. and Luizão, F. and Piedade, M. T. F. and Schöngart, J.}, title = {The Biogeochemistry of the Main Forest Vegetation Types in Amazonia}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {225--266}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Buscardo, E., Gem, J., Schmidt, S.K., Silva, A.L.C., Ramos, R.T.J., Barbosa, S.M.R., Andrade, S.S., Costa, R.D., Souza, A.P., Freitas, H., Cunha, H.B. and Nagy, L. | Of mammals and bacteria in a rainforest: Temporal dynamics of soil bacteria in response to simulated N pulse from mammalian urine [BibTeX] |
2017 | Functional Ecology, pp. 1-12 | article | DOI |
BibTeX:
@article{buscardo_mammals_2017, author = {Buscardo, Erika and Gem, József and Schmidt, Steven K. and Silva, Artur L. C. and Ramos, Rommel T. J. and Barbosa, Silvanira M. R. and Andrade, Soraya S. and Costa, Ricardo Dalla and Souza, Anete P. and Freitas, Helena and Cunha, Hillândia B. and Nagy, Laszlo}, title = {Of mammals and bacteria in a rainforest: Temporal dynamics of soil bacteria in response to simulated N pulse from mammalian urine}, journal = {Functional Ecology}, year = {2017}, pages = {1--12}, doi = {https://doi.org/10.1111/1365-2435.12998} } |
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Burt, A., Boni Vicari, M., da Costa, A.C.L., Coughlin, I., Meir, P., Rowland, L. and Disney, M. | New insights into large tropical tree mass and structure from direct harvest and terrestrial lidar | 2021 | Royal Society Open Science Vol. 8(2), pp. 201458 |
article | DOI URL |
Abstract: A large portion of the terrestrial vegetation carbon stock is stored in the above-ground biomass (AGB) of tropical forests, but the exact amount remains uncertain, partly owing to the lack of measurements. To date, accessible peer-reviewed data are available for just 10 large tropical trees in the Amazon that have been harvested and directly measured entirely via weighing. Here, we harvested four large tropical rainforest trees (stem diameter: 0.6–1.2 m, height: 30–46 m, AGB: 3960–18 584 kg) in intact old-growth forest in East Amazonia, and measured above-ground green mass, moisture content and woody tissue density. We first present rare ecological insights provided by these data, including unsystematic intra-tree variations in density, with both height and radius. We also found the majority of AGB was usually found in the crown, but varied from 42 to 62%. We then compare non-destructive approaches for estimating the AGB of these trees, using both classical allometry and new lidar-based methods. Terrestrial lidar point clouds were collected pre-harvest, on which we fitted cylinders to model woody structure, enabling retrieval of volume-derived AGB. Estimates from this approach were more accurate than allometric counterparts (mean tree-scale relative error: 3% versus 15%), and error decreased when up-scaling to the cumulative AGB of the four trees (1% versus 15%). Furthermore, while allometric error increased fourfold with tree size over the diameter range, lidar error remained constant. This suggests error in these lidar-derived estimates is random and additive. Were these results transferable across forest scenes, terrestrial lidar methods would reduce uncertainty in stand-scale AGB estimates, and therefore advance our understanding of the role of tropical forests in the global carbon cycle. | |||||
BibTeX:
@article{burt_new_2021, author = {Burt, Andrew and Boni Vicari, Matheus and da Costa, Antonio C. L. and Coughlin, Ingrid and Meir, Patrick and Rowland, Lucy and Disney, Mathias}, title = {New insights into large tropical tree mass and structure from direct harvest and terrestrial lidar}, journal = {Royal Society Open Science}, year = {2021}, volume = {8}, number = {2}, pages = {201458}, url = {https://royalsocietypublishing.org/doi/abs/10.1098/rsos.201458}, doi = {https://doi.org/10.1098/rsos.201458} } |
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Bulbovas, P., de Souza, S.R., de Moraes, R.M., Luizao, F. and Artaxo, P. | Soybean 'Tracaja' seedlings exposed to ozone under controlled conditions | 2007 | Pesquisa Agropecuaria Brasileira Vol. 42(5), pp. 641-646 |
article | URL |
Abstract: The objective of this work was to assess initial growth, biomass production, gas exchange and antioxidative defenses of soybean 'Tracaja' seedlings, cultivated in the Amazonian region, exposed to ozone under controlled conditions. Seeds germinated in pots were placed in two chambers, one with filtered air (AF) and other with filtered air plus 30 ppb of ozone (AF + O-3). At 10 and 20 days after sowing, gas exchange, growth and biomass were measured; at 20 days after sowing, antioxidative defenses (ascorbic acid and superoxide dismutase) were analyzed. Net photosynthesis, stomatal conductance, transpiration rate, height, leaf area and biomass were 16, 27, 11, 22, 29 and 18% smaller, respectively, in AF + O-3 at 10 days after sowing. At 20 days after sowing, besides this parameters, root length, stem diameter and root:shoot ratio were 10, 15 and 12% smaller, respectively, although ascorbic acid concentrations and superoxide dismutase activity increased. Soybean 'Tracaja' seedlings have low tolerance to concentration of 30 ppb of ozone. | |||||
BibTeX:
@article{bulbovas_soybean_2007, author = {Bulbovas, Patricia and de Souza, Silvia Ribeiro and de Moraes, Regina Maria and Luizao, Flavio and Artaxo, Paulo}, title = {Soybean 'Tracaja' seedlings exposed to ozone under controlled conditions}, journal = {Pesquisa Agropecuaria Brasileira}, year = {2007}, volume = {42}, number = {5}, pages = {641--646}, url = {://WOS:000247565500005} } |
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Bruno, R.D., da Rocha, H.R., de Freitas, H.C., Goulden, M.L. and Miller, S.D. | Soil moisture dynamics in an eastern Amazonian tropical forest | 2006 | Hydrological Processes Vol. 20(12), pp. 2477-2489 |
article | DOI URL |
Abstract: We used frequency-domain reflectometry to make continuous, high-resolution measurements for 22 months of the soil moisture to a depth of 10 m in an Amazonian rain forest. We then used these data to determine how soil moisture varies on diel, seasonal and multi-year timescales, and to better understand the quantitative and mechanistic relationships between soil moisture and forest evapotranspiration. The mean annual precipitation at the site was over 1900 mm. The field capacity was approximately 0.53 m(3) m(-3) and was nearly uniform with soil depth. Soil moisture decreased at all levels during the dry season, with the minimum of 0.38 m(3) m(-3) at 3 m beneath the surface. The moisture in the upper I m showed a strong diel cycle with daytime depletion due to evapotranspiration. The moisture beneath 1 m declined during both day and night due to the combined effects of evapotranspiration, drainage and a nighttime upward movement of water. The depth of active water withdrawal changed markedly over the year. The upper 2 m of soil supplied similar to 56% of the water used for evapotranspiration in the wet season and similar to 28% of the water used in the dry season. The zone of active water withdrawal extended to a depth of at least 10 m. The day-to-day rates of moisture withdrawal from the upper 10 m of soil during rain-free periods agreed well with simultaneous measurements of whole-forest evapotranspiration made by the eddy covariance technique. The forest at the site was well adapted to the normal cycle of wet and dry seasons, and the dry season had only a small effect on the rates of land-atmosphere water vapour exchange. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{bruno_soil_2006, author = {Bruno, Rogerio D. and da Rocha, Humberto R. and de Freitas, Helber C. and Goulden, Michael L. and Miller, Scott D.}, title = {Soil moisture dynamics in an eastern Amazonian tropical forest}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2477--2489}, url = {://WOS:000239670800002 http://onlinelibrary.wiley.com/store/10.1002/hyp.6211/asset/6211_ftp.pdf?v=1&t=h6hxui1y&s=1900eb9c16c49d908343a02caa616e943d9c096d}, doi = {https://doi.org/10.1002/hyp.6211} } |
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Brum, M., Vadeboncoeur, M.A., Ivanov, V., Asbjornsen, H., Saleska, S., Alves, ..F., Penha, D., Dias, J.D., Aragão, L.E., Barros, F., Bittencourt, P., Pereira, L. and Oliveira, R. | Hydrological niche segregation defines forest structure and drought tolerance strategies in a seasonal Amazon forest [BibTeX] |
2018 | Journal of Ecology | article | DOI |
BibTeX:
@article{brum_hydrological_2018, author = {Brum, M. and Vadeboncoeur, M. A. and Ivanov, V. and Asbjornsen, H. and Saleska, S. and Alves, . F. and Penha, D. and Dias, J. D. and Aragão, L. E.O.C. and Barros, F.V. and Bittencourt, P.R. and Pereira, L. and Oliveira, R.S.}, title = {Hydrological niche segregation defines forest structure and drought tolerance strategies in a seasonal Amazon forest}, journal = {Journal of Ecology}, year = {2018}, doi = {https://doi.org/10.1111/1365-2745.13022} } |
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Brown, I.F. | Learning to Question: The Roles of Multiple Hypotheses, Successive Approximations, Balloons and Toilet Paper in University Science Programs of Southwestern Amazonia | 2008 | Journal of Science Education and Technology Vol. 17(3), pp. 236-241 |
article | DOI URL |
Abstract: Learning to question is essential for determining pathways of conservation and development in southwestern Amazonia during a time of rapid global environmental change. Teaching such an approach in graduate science programs in regional universities can be done using play-acting and simulation exercises. Multiple working hypotheses help students learn to question their own research results and expert witnesses. The method of successive approximations enables students to question the results of complex calculations, such as estimates of forest biomass. Balloons and rolls of toilet paper provide means of questioning two-dimensional representations of a three-dimensional Earth and the value of pi. Generation of systematic errors can illustrate the pitfalls of blind acceptance of data. While learning to question is essential, it is insufficient by itself; students must also learn how to be solutionologists in order to satisfy societal demands for solutions to environmental problems. A little irreverence can be an excellent didactic tool for helping students develop the skills necessary to lead conservation and development efforts in the region. | |||||
BibTeX:
@article{brown_learning_2008, author = {Brown, I. Foster}, title = {Learning to Question: The Roles of Multiple Hypotheses, Successive Approximations, Balloons and Toilet Paper in University Science Programs of Southwestern Amazonia}, journal = {Journal of Science Education and Technology}, year = {2008}, volume = {17}, number = {3}, pages = {236--241}, url = {://WOS:000270139200005 http://www.springerlink.com/content/71521761r8834l76/fulltext.pdf}, doi = {https://doi.org/10.1007/s10956-008-9093-7} } |
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Browder, J.O., Wynne, R.H. and Pedlowski, M.A. | Agroforestry diffusion and secondary forest regeneration in the Brazilian Amazon: further findings from the Rondonia Agroforestry Pilot Project (1992-2002) | 2005 | Agroforestry Systems Vol. 65(2), pp. 99-111 |
article | DOI URL |
Abstract: In July 1992 the Rondonia Agroforestry Pilot Project ( RAPP) was launched in two agricultural municipalities ( Nova Uniao and Alto Paraiso) in the western Brazilian Amazon State of Rondonia. The purpose of the RAPP was to assess the conditions under which colonist farmers in the western Amazon would integrate agroforestry plantings into their small-scale farming systems and to assess the performance of those plantings over time. An experimental group consisting of 50 small-scale farmers was selected to participate. Plots were designed to accommodate between 3 and 25 different species, each producing one or more commodities with local market potential ( hardwood, fruits, nuts, latexes, oils). Farmers planted seedlings typically on a 1-ha plot, located and designed by each farmer with the advice of a professional Brazilian extensionist. During the first phase of the project ( 1992 - 1998), the growth performance of the seedlings and changes in household characteristics were monitored on an annual basis. By 2002, 32 (64.0%) of the original 50 agroforest plots were found in place. This paper updates the research findings based on a 2002 follow-up visit to these 32 farms. In addition to growth performance, the authors' found that 17.95% of the farms in the neighboring control group had planted trees and other agroforest crops between 1992 and 2002, compared to only 5.38% of farms outside the project area, suggesting spontaneous diffusion. The authors also found a potentially synergistic relationship between agroforestry and secondary forest regeneration with the use of satellite image analysis. The experience of the RAPP indicates that colonist farmers in Amazonia can be successful managers of agroforest plots with minimal external inputs over the long-term ( 10 years). | |||||
BibTeX:
@article{browder_agroforestry_2005, author = {Browder, J. O. and Wynne, R. H. and Pedlowski, M. A.}, title = {Agroforestry diffusion and secondary forest regeneration in the Brazilian Amazon: further findings from the Rondonia Agroforestry Pilot Project (1992-2002)}, journal = {Agroforestry Systems}, year = {2005}, volume = {65}, number = {2}, pages = {99--111}, url = {://WOS:000228920900003 http://www.springerlink.com/content/j23437653t120577/fulltext.pdf}, doi = {https://doi.org/10.1007/s10457-004-6375-9} } |
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Browder, J.O., Pedlowski, M.A., Walker, R., Wynne, R.H., Summers, P.M., Abad, A., Becerra-Cordoba, N. and Mil-Homens, J. | Revisiting theories of frontier expansion in the Brazilian Amazon: A survey of the colonist farming population in Rondonia's post-frontier, 1992-2002 | 2008 | World Development Vol. 36(8), pp. 1469-1492 |
article | DOI URL |
Abstract: In the 1970s, extensive areas of Brazilian Amazon were settled by landless farmers. These internal migrations prompted theoretical scholarship on the nature and Outcomes of frontier expansion from three general frameworks: the capitalist penetration thesis, the inter-sectoral articulation thesis, and the household life-cycle thesis. This paper reports selected findings of a 10-year (1992-2002) panel study of 240 farms in three settlement areas in Rondonia. The empirical findings of this longitudinal survey research do not unequivocally confirm my of these theses. Instead, elements of each emerge from the data analysis inviting a more locally nuanced, pluralistic approach to understanding the frontier colonization experience. (c) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{browder_revisiting_2008, author = {Browder, John O. and Pedlowski, Marcos A. and Walker, Robert and Wynne, Randolph H. and Summers, Percy M. and Abad, Ana and Becerra-Cordoba, Nancy and Mil-Homens, Joao}, title = {Revisiting theories of frontier expansion in the Brazilian Amazon: A survey of the colonist farming population in Rondonia's post-frontier, 1992-2002}, journal = {World Development}, year = {2008}, volume = {36}, number = {8}, pages = {1469--1492}, url = {://WOS:000259050600009}, doi = {https://doi.org/10.1016/j.worlddev.2007.08.008} } |
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Browder, J.O., Pedlowski, M.A. and Summers, P.M. | Land use patterns in the Brazilian Amazon: Comparative farm-level evidence from Rondonia | 2004 | Human Ecology Vol. 32(2), pp. 197-224 |
article | DOI URL |
Abstract: Since the 1970s the Brazilian Amazon has received over 1 million migrant farm households from other regions of the country, many of whom were attracted to government-sponsored frontier settlement programs that offered free tropical forest land. As a result, pressures on tropical forests have intensified along several settlement corridors throughout the region. Despite their importance as agents of landscape change, surprisingly little is known about the land use practices of these farmers. This paper briefly reviews the research literature on smallholder land use patterns in Amazonia, describes the recent history of one important agricultural land settlement program in the western Brazilian Amazon state of Rondonia, and, based on 240 household surveys conducted in three separate settlement locations in the state, highlights key differences in land use patterns among the rural population. Typologies of farming systems are presented on the basis of cluster analysis of land use data and ANOVA tests. The findings indicate considerable complexity and heterogeneity in smallholder farming systems. Spatial variations in farming system types may be due to geographic differences in soil regimes, the social histories of specific communities, and site-specific responses to exogenous variables. | |||||
BibTeX:
@article{browder_land_2004, author = {Browder, J. O. and Pedlowski, M. A. and Summers, P. M.}, title = {Land use patterns in the Brazilian Amazon: Comparative farm-level evidence from Rondonia}, journal = {Human Ecology}, year = {2004}, volume = {32}, number = {2}, pages = {197--224}, url = {://WOS:000220204300004 http://www.springerlink.com/content/j0k8341218218272/fulltext.pdf}, doi = {https://doi.org/10.1023/B:HUEC.0000019763.73998.c9} } |
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Brondizio, E.S. and Moran, E.F. | Human dimensions of climate change: the vulnerability of small farmers in the Amazon | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1803-1809 |
article | DOI URL |
Abstract: This paper argues for a twofold perspective on human adaptation to climate change in the Amazon. First, we need to understand the processes that mediate perceptions of environmental change and the behavioural responses at the levels of the individual and the local population. Second, we should take into account the process of production and dissemination of global and national climate information and models to regional and local populations, especially small farmers. We discuss the sociocultural and environmental diversity of small farmers in the Amazon and their susceptibility to climate change associated with drought, flooding and accidental fire. Using survey, ethnographic and archival data from study areas in the state of Para, we discuss farmers' sources of knowledge and long-term memory of climatic events, drought and accidental fire; their sources of climate information; their responses to drought and fire events and the impact of changing rainfall patterns on land use. We highlight the challenges of adaptation to climate change created by the influence of migration and family turnover on collective action and memory, the mismatch of scales used to monitor and disseminate climate data and the lack of extension services to translate large-scale forecasts to local needs. We found that for most farmers, memories of extended drought tend to decrease significantly after 3 years. Over 50% of the farmers interviewed in 2002 did not remember as significant the El Nino Southern Oscillation (ENSO) drought of 1997/1998. This helps explain why approximately 40% of the farmers have not changed their land-use behaviours in the face of the strongest ENSO event of the twentieth century. | |||||
BibTeX:
@article{brondizio_human_2008, author = {Brondizio, Eduardo S. and Moran, Emilio F.}, title = {Human dimensions of climate change: the vulnerability of small farmers in the Amazon}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1803--1809}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500012 http://rstb.royalsocietypublishing.org/content/363/1498/1803.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0025} } |
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Brondizio, E.S., Cak, A., Caldas, M.M., Mena, C., Bilsborrow, R., Futemma, C.T., Ludewigs, T., Moran, E.F. and Batistella, M. | Small Farmers and Deforestation in Amazonia | 2009 | Vol. 186Amazonia and Global Change, pp. 117-144 |
incollection | DOI URL |
Abstract: This chapter discusses the relationship between small farmers' land use and deforestation, with particular attention paid to the past 30 years of Amazonian colonization in Brazil and Ecuador. Our analysis calls attention to common features uniting different social groups as small farmers (e.g., social identity, access to land and resources, technology, market, and credit), as well as the variability between small farmers in terms of time in the region (from native populations to recent colonists), contribution to regional deforestation, types of land use systems. At a regional level, small farmers contribute to the majority of deforestation events, but are responsible for only a fraction of the total deforested area in Amazonia. We discuss three misconceptions that have been used to define small farmers and their contribution to the regional economy, development, and deforestation: (1) small farmers have backward land use systems associated with low productivity and extensive deforestation and subsistence production, (2) small farmers contribute to Amazonian deforestation as much as large farmers, and (3) small fanners, particularly colonist farmers, follow an inexorable path of deforestation unless curbed by government action. We conclude the chapter discussing their growing regional importance and the need for more inclusive public policies concerning infrastructure and services and valorization of resources produced in rural areas of Amazonia. | |||||
BibTeX:
@incollection{keller_small_2009, author = {Brondizio, Eduardo S. and Cak, Anthony and Caldas, Marcellus M. and Mena, Carlos and Bilsborrow, Richard and Futemma, Celia T. and Ludewigs, Thomas and Moran, Emilio F. and Batistella, Mateus}, title = {Small Farmers and Deforestation in Amazonia}, booktitle = {Amazonia and Global Change}, year = {2009}, volume = {186}, pages = {117--144}, url = {://WOS:000289443400008 http://www.agu.org/books/gm/v186/2008GM000716/2008GM000716.shtml}, doi = {https://doi.org/10.1029/2008gm000716} } |
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Brondizio, E.S. | Landscapes of the Past, Footprints of the Future - Historical ecology and the study of contemporary land-use change in the Amazon [BibTeX] |
2006 | Time and Complexity in Historical Ecology: STUDIES IN THE NEOTROPICAL LOWLANDS, pp. 365-405 | incollection | URL |
BibTeX:
@incollection{balee_landscapes_2006, author = {Brondizio, E. S.}, title = {Landscapes of the Past, Footprints of the Future - Historical ecology and the study of contemporary land-use change in the Amazon}, booktitle = {Time and Complexity in Historical Ecology: STUDIES IN THE NEOTROPICAL LOWLANDS}, year = {2006}, pages = {365--405}, url = {://WOS:000242925500013} } |
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Brondizio, E.S. | Revisiting Amazonia circa 1492 [BibTeX] |
2003 | Science Vol. 302(5653), pp. 2067-2068 |
article | URL |
BibTeX:
@article{brondizio_revisiting_2003, author = {Brondizio, E. S.}, title = {Revisiting Amazonia circa 1492}, journal = {Science}, year = {2003}, volume = {302}, number = {5653}, pages = {2067--2068}, note = {Edition: 2003/12/31}, url = {://WOS:000187385200020} } |
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Broedel, E., von Randow, C., Cuartas, L.A., Satyamurty, P., de Araújo, A.C., Cândido, L.A., Tomasella, J., Nobre, A.D. and Tourigny, E. | A comparison of the spatial heterogeneities of surface fluxes simulated by INLAND model with observations at a valley and a nearby plateau stations in Central Amazon Forest | 2022 | SN Applied Sciences Vol. 4(6), pp. 174 |
article | DOI URL |
Abstract: An improved version of the Integrated Land Surface Model (INLAND), incorporating the physical, ecological and hydrological parameters and processes pertaining to two subclasses of tropical forest in the central Amazon basin, a poorly drained flat plateau and a well-drained adjacent broad valley, is used to simulate the hydrological, energy and CO2 fluxes. The model is forced with observed meteorological data. The experimental output data from the model runs are compared with observational data at the two locations. The seasonal variabilities of water table depth at the valley site and the soil moisture at the plateau site are satisfactorily simulated. The two locations exhibit large differences in energy, carbon and water fluxes, both in the simulations and in the observations. Results validate the INLAND model and indicate the need for incorporating sub-grid scale variability in the relief, soil type and vegetation type attributes to improve the representation of the Amazonian ecosystems in land-surface models. | |||||
BibTeX:
@article{broedel_comparison_2022, author = {Broedel, Elisângela and von Randow, Celso and Cuartas, Luz Adriana and Satyamurty, Prakki and de Araújo, Alessandro Carioca and Cândido, Luiz Antônio and Tomasella, Javier and Nobre, Antônio Donato and Tourigny, Etienne}, title = {A comparison of the spatial heterogeneities of surface fluxes simulated by INLAND model with observations at a valley and a nearby plateau stations in Central Amazon Forest}, journal = {SN Applied Sciences}, year = {2022}, volume = {4}, number = {6}, pages = {174}, url = {https://doi.org/10.1007/s42452-022-05026-8}, doi = {https://doi.org/10.1007/s42452-022-05026-8} } |
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Broedel, E., Tomasella, J., Cândido, L.A. and Von Randow, C. | Deep soil water dynamics in an undisturbed primary forest in central Amazonia: differences between normal years and the 2005 drought [BibTeX] |
2017 | Hydrological Processes Vol. 31, pp. 1749-1759 |
article | DOI |
BibTeX:
@article{broedel_deep_2017, author = {Broedel, Elisângela and Tomasella, Javier and Cândido, Luiz Antônio and Von Randow, Celso}, title = {Deep soil water dynamics in an undisturbed primary forest in central Amazonia: differences between normal years and the 2005 drought}, journal = {Hydrological Processes}, year = {2017}, volume = {31}, pages = {1749--1759}, doi = {https://doi.org/10.1002/hyp.11143} } |
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Broedel, E., Randow, C.V., Cuartas, L.A., Nobre, A.D., Araújo, A.C.d., Kruijt, B., Tourigny, E., Cândido, L.A., Hodnett, M. and Tomasella, J. | Simulation of Surface Fluxes in Two Distinct Environments along a Topographic Gradient in a Central Amazonian Forest using the INtegrated LAND Surface Model [BibTeX] |
2017 | Hydrol. Earth Syst. Sci. Discuss. | article | DOI |
BibTeX:
@article{broedel_simulation_2017, author = {Broedel, Elisângela and Randow, Celso Von and Cuartas, Luz Adriana and Nobre, Antonio Donato and Araújo, Alessandro Carioca de and Kruijt, Bart and Tourigny, Etienne and Cândido, Luiz Antônio and Hodnett, Martin and Tomasella, Javier}, title = {Simulation of Surface Fluxes in Two Distinct Environments along a Topographic Gradient in a Central Amazonian Forest using the INtegrated LAND Surface Model}, journal = {Hydrol. Earth Syst. Sci. Discuss.}, year = {2017}, doi = {https://doi.org/10.5194/hess-2017-203} } |
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Broadbent, E., Zarin, D., Asner, G.P., Pena-Claros, M., Cooper, A. and Littell, R. | Recovery of forest structure and spectral properties after selective logging in lowland Bolivia | 2006 | Ecological Applications Vol. 16(3), pp. 1148-1163 |
article | DOI URL |
Abstract: Effective monitoring of selective logging from remotely sensed data requires an understanding of the spatial and temporal thresholds that constrain the utility of those data, as well as the structural and ecological characteristics of forest disturbances that are responsible for those constraints. Here we assess those thresholds and characteristics within the context of selective logging in the Bolivian Amazon. Our study combined field measurements of the spatial and temporal dynamics of felling gaps and skid trails ranging from textless I to 19 months following reduced-impact logging in a forest in lowland Bolivia with remote-sensing measurements from simultaneous monthly ASTER satellite overpasses. A probabilistic spectral mixture model (AutoMCU) was used to derive per-pixel fractional cover estimates of photosynthetic vegetation (PV), non-photosynthetic vegetation (NPV), and soil. Results were compared with the normalized difference in vegetation index (NDVI). The forest studied had considerably lower basal area and harvest volumes than logged sites in the Brazilian Amazon where similar remote-sensing analyses have been performed. Nonetheless, individual felling-gap area was positively correlated with canopy openness, percentage liana coverage, rates of vegetation regrowth, and height of remnant NPV. Both liana growth and NPV occurred primarily in the crown zone of the felling gap, whereas exposed soil was limited to the trunk zone of the gap. In felling gaps textgreater 400 m(2), NDVI, and the PV and NPV fractions, were distinguishable from unlogged forest values for up to six months after logging; felling gaps textless 400 m(2) were distinguishable for up to three months after harvest, but we were entirely unable to distinguish skid trails from our analysis of the spectral data. | |||||
BibTeX:
@article{broadbent_recovery_2006, author = {Broadbent, E.N. and Zarin, D.J. and Asner, G. P. and Pena-Claros, M. and Cooper, A. and Littell, R.}, title = {Recovery of forest structure and spectral properties after selective logging in lowland Bolivia}, journal = {Ecological Applications}, year = {2006}, volume = {16}, number = {3}, pages = {1148--1163}, note = {Edition: 2006/07/11}, url = {://WOS:000238451500026 http://www.esajournals.org/doi/pdf/10.1890/1051-0761%282006%29016%5B1148%3AROFSAS%5D2.0.CO%3B2}, doi = {https://doi.org/10.1890/1051-0761(2006)016%5B1148:rofsas%5D2.0.co;2} } |
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Broadbent, E.N., Asner, G.P., Pena-Claros, M., Palace, M. and Soriano, M. | Spatial partitioning of biomass and diversity in a lowland Bolivian forest: Linking field and remote sensing measurements | 2008 | Forest Ecology and Management Vol. 255(7), pp. 2602-2616 |
article | DOI URL |
Abstract: Large-scale inventories of forest biomass and structure are necessary for both understanding carbon dynamics and conserving biodiversity. High-resolution satellite imagery is starting to enable structural analysis of tropical forests over large areas, but we lack an understanding of how tropical forest biomass links to remote sensing. We quantified the spatial distribution of biomass and tree species diversity over 4 ha in a Bolivian lowland moist tropical forest, and then linked our field measurements to high-resolution Quickbird satellite imagery. Our field measurements showed that emergent and canopy dominant trees, being those directly visible from nadir remote sensors, comprised the highest diversity of tree species, represented 86% of all tree species found in our study plots, and contained the majority of forest biomass. Emergent trees obscured 1-15 trees with trunk diameters (at 1.3 m, diameter at breast height (DBH)) textgreater= 20 cm, thus hiding 30-50% of forest biomass from nadir viewing. Allometric equations were developed to link remotely visible crown features to stand parameters, showing that the maximum tree crown length explains 50-70% of the individual tree biomass. We then developed correction equations to derive aboveground forest biomass, basal area, and tree density from tree crowns visible to nadir satellites. We applied an automated tree crown delineation procedure to a high-resolution panchromatic Quickbird image of our study area, which showed promise for identification of forest biomass at community scales, but which also highlighted the difficulties of remotely sensing forest structure at the individual tree level. (c) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{broadbent_spatial_2008, author = {Broadbent, Eben N. and Asner, Gregory P. and Pena-Claros, Marielos and Palace, Michael and Soriano, Marlene}, title = {Spatial partitioning of biomass and diversity in a lowland Bolivian forest: Linking field and remote sensing measurements}, journal = {Forest Ecology and Management}, year = {2008}, volume = {255}, number = {7}, pages = {2602--2616}, url = {://WOS:000256143900055}, doi = {https://doi.org/10.1016/j.foreco.2008.01.044} } |
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Broadbent, E.N., Asner, G.P., Keller, M., Knapp, D.E., Oliveira, P.J.C. and Silva, J.N. | Forest fragmentation and edge effects from deforestation and selective logging in the Brazilian Amazon | 2008 | Biological Conservation Vol. 141(7), pp. 1745-1757 |
article | DOI URL |
Abstract: Forest fragmentation results from deforestation and disturbance, with subsequent edge effects extending deep into remaining forest areas. No study has quantified the effects of both deforestation and selective logging, separately and combined, on forest fragmentation and edge effects over large regions. The main objectives of this study were to: (1) quantify the rates and extent of forest fragmentation from deforestation and logging within the Brazilian Amazon, and (2) contextualize the spatio-temporal dynamics of this forest fragmentation through a literature review of potential ecological repercussions of edge creation. Using GIS and remote sensing, we quantified forest fragmentation defined as both increases in the forest edge-to-area ratio and number of forest fragments - and edge-effected forest occurring from these activities across more than 1.1 million km(2) of the Brazilian Amazon from 1999 to 2002. Annually, deforestation and logging generated similar to 32,000 and 38,000 km of new forest edge while increasing the edge-to-area ratio of remaining forest by 0.14 and 0.15, respectively. Combined deforestation and logging increased the edge-to-area ratio of remaining forest by 65% over our study period, while generating 5539 and 3383 new forest fragments, respectively. Although we found that 90% of individual forest fragments were smaller than 4 km(2), we also found that 50% of the remaining intact forests were located in contiguous forest areas greater than 35,000 km(2). We then conducted a literature review documenting 146 edge effects and found that these penetrated to a median distance of 100 m, a distance encompassing 6.4% of all remaining forests in our study region in the year 2002, while 53% of forests were located within two km of an edge. Annually deforestation and logging increased the proportion of edge-forest by 0.8% and 3.1%, respectively. As a result of both activities, the total proportion of edge-forest increased by 2.6% per year, while the proportion within 100-m increased by 0.5%. Over our study period, deforestation resulted in an additional similar to 3000 km(2) of edge-forest, whereas logging generated similar to 20,000 km(2), as it extended deep into intact forest areas. These results show the large extent and rapid expansion of previously unquantified soft-edges throughout the Amazon and highlight the need for greater research into their ecological impacts. (C) 2008 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{broadbent_forest_2008, author = {Broadbent, Eben N. and Asner, Gregory P. and Keller, Michael and Knapp, David E. and Oliveira, Paulo J. C. and Silva, Jose N.}, title = {Forest fragmentation and edge effects from deforestation and selective logging in the Brazilian Amazon}, journal = {Biological Conservation}, year = {2008}, volume = {141}, number = {7}, pages = {1745--1757}, url = {://WOS:000258306300002}, doi = {https://doi.org/10.1016/j.biocon.2008.04.024} } |
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Brito, J., Wurm, F., Yañez, S., Assunção, J.V.d., Godoy, J. and Artaxo, P. | Vehicular Emission Ratios of VOCs in a Megacity Impacted by Extensive Ethanol Use: Results of Ambient Measurements in São Paulo, Brazil [BibTeX] |
2015 | Environmental Science & Policy and Technology Vol. 49(19), pp. 11381-11387 |
article | DOI |
BibTeX:
@article{brito_vehicular_2015, author = {Brito, J. and Wurm, F. and Yañez, S.A.M. and Assunção, J. V. de and Godoy, J.M. and Artaxo, P.}, title = {Vehicular Emission Ratios of VOCs in a Megacity Impacted by Extensive Ethanol Use: Results of Ambient Measurements in São Paulo, Brazil}, journal = {Environmental Science & Policy and Technology}, year = {2015}, volume = {49}, number = {19}, pages = {11381--11387}, doi = {https://doi.org/10.1021/acs.est.5b03281} } |
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Brito, J., Rizzo, L.V., Morgan, W.T., Coe, H., Johnson, B., Haywood, J., Longo, K., Freitas, S., Andreae, M.O. and Artaxo, P. | Ground based aerosol characterization during the South American Biomass Burning Analysis (SAMBBA) field experiment [BibTeX] |
2014 | Atmos. Chem. Phys. Vol. 14, pp. 12069-12083 |
article | DOI |
BibTeX:
@article{brito_ground_2014, author = {Brito, J. and Rizzo, L. V. and Morgan, W. T. and Coe, H. and Johnson, B. and Haywood, J. and Longo, K. and Freitas, S. and Andreae, M. O. and Artaxo, P.}, title = {Ground based aerosol characterization during the South American Biomass Burning Analysis (SAMBBA) field experiment}, journal = {Atmos. Chem. Phys.}, year = {2014}, volume = {14}, pages = {12069--12083}, note = {Section: www.atmos-chem-phys-discuss.net/14/12279/2014/}, doi = {https://doi.org/10.5194/acpd-14-12279-2014} } |
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Brito, A.P.d., Wahnfried, I.D., Ferreira, S.J.F. and Bastos, J.H.B.d. | Análise comparativa entre métodos de estimativa de recarga para uma microbacia na Reserva Florestal Adolpho Ducke, Manaus - AM | 10 | Geologia USP. Série Científica Vol. 21(3), pp. 59-73 |
article | DOI URL |
Abstract: <p>A recarga é um elemento-chave do ciclo hidrológico, sendo indispensável para a gestão integrada dos recursos hídricos. Este estudo objetivou quantificar e comparar as taxas de recarga direta de um aquífero freático localizado em uma região de floresta primária contígua a Manaus utilizando os métodos&nbsp; balanço hídrico (BH), variação do nível da água (VNA) e estimativa darcyana (ED). Foram obtidos dados de precipitação e temperatura atmosférica de 2013 a 2015 da estação meteorológica localizada na Reserva Florestal Adolpho Ducke (RFAD). Medições de nível da água subterrânea e ensaios para determinação&nbsp; de condutividade hidráulica foram executados em sete piezômetros instalados em microbacia de drenagem da RFAD. A vazão específica (Sy) foi determinada em amostras de solo indeformadas. Os resultados do método do BH indicam taxa de recarga de 47% (1.583 mm) em 2013, de 46% (1.277 mm) em 2014 e de 20% (680 mm) em 2015. A precipitação em 2014 foi 18% menor do que em 2013, e a de 2015 foi 21% menor do que em 2014, por causa do fenômeno El Niño, gerando redução significativa da recarga apenas no último ano. Os registros de nível da água subterrânea para ED foram feitos entre fevereiro e julho de 2013, gerando estimativa de recarga de 28% (624 mm) da precipitação. Aplicando-se o método de VNA foi estimada uma taxa de recarga de 52% (2.229 mm) para o período de fevereiro de 2014 a agosto de 2015. Os resultados indicam maior consistência entre BH e VNA. As taxas de recarga aqui obtidas são superiores às determinadas em situações hidrogeológicas análogas em outras regiões do país.&nbsp;</p> | |||||
BibTeX:
@article{brito_alise_10, author = {Brito, Alderlene Pimentel de and Wahnfried, Ingo Daniel and Ferreira, Sávio José Filgueiras and Bastos, João Hilário Borges de}, title = {Análise comparativa entre métodos de estimativa de recarga para uma microbacia na Reserva Florestal Adolpho Ducke, Manaus - AM}, journal = {Geologia USP. Série Científica}, year = {10}, volume = {21}, number = {3}, pages = {59--73}, url = {https://www.revistas.usp.br/guspsc/article/view/191182}, doi = {https://doi.org/10.11606/issn.2316-9095.v21-154769} } |
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Brito, A.P.d., Tomasella, J., Wahnfried, I.D., Candido, L.A., Monteiro, M.T. and Filgueiras, S.J.F. | Relação entre precipitação e recarga de águas subterrâneas na Amazônia Central | 1 | Águas Subterrâneas Vol. 34(1), pp. 39-49 |
article | DOI URL |
Abstract: <div><table cellspacing="0" cellpadding="0" align="left"><tbody><tr><td align="left" valign="top"><div><p class="Resumoeabstract">A água subterrânea na Amazônia é de fundamental importância na manutenção dos serviços ecossistêmicos e para atender demandas humanas. Apesar da existência de grandes corpos de água doce na região, as demandas de abastecimento são atendidas a partir de fontes subterrâneas, majoritariamente freáticas. De forma geral, demandas crescentes do recurso subterrâneo associadas ao crescimento demográfico e padrões de uso do solo podem induzir a alterações nas relações de balanço hídrico e, presumidamente também, as relações entre precipitação-recarga. Somam-se, a esses fatores, efeitos dos eventos climáticos interanuais como o ENOS em suas distintas manifestações: El Niño e La Niña. O objetivo deste estudo é correlacionar as recargas anuais e episódicas nos aquíferos Alter do Chão e Trombetas com a precipitação entre 2011 a 2018, tendo como foco especial o evento de El Niño de 2015-2016. A análise consiste na estimativa das taxas de recarga a partir do método Variação do Nível de Água (VNA) e na comparação das variações do nível da água subterrânea ao déficit total no armazenamento de água para o período. Padrões de comportamento interanuais do nível freático correlacionam-se com a variabilidade observada para a precipitação. A recarga média anual para os aquíferos Alter do Chão e Trombetas foi de 35% (572 mm) para uma precipitação anual de 1647 mm, e 24%, ou seja, 473 mm de 1954 mm precipitados, respectivamente. Os níveis freáticos mínimos ocorreram em janeiro de 2016. Este efeito indica que o ENOS pode gerar diminuições no volume total de água armazenado em aquíferos na Amazônia durante e alguns meses após sua ocorrência.</p></div></td></tr></tbody></table></div> | |||||
BibTeX:
@article{brito_relacao_1, author = {Brito, Alderlene Pimentel de and Tomasella, Javier and Wahnfried, Ingo Daniel and Candido, Luiz Antonio and Monteiro, Maria Terezinha and Filgueiras, Sávio José Ferreira}, title = {Relação entre precipitação e recarga de águas subterrâneas na Amazônia Central}, journal = {Águas Subterrâneas}, year = {1}, volume = {34}, number = {1}, pages = {39--49}, note = {Section: Artigos}, url = {https://aguassubterraneas.abas.org/asubterraneas/article/view/29616}, doi = {https://doi.org/10.14295/ras.v34i1.29616} } |
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Brito, A.P.d., Silva, N.C.d., Tomasella, J., Ferreira, S.J.F. and Monteiro, M.T.F. | Análise do índice de Anomalia de Chuva e Tendência de Precipitação para Estações Pluviométricas na Amazônia Central. [BibTeX] |
2022 | Revista Brasileira de Meteorologia Vol. 37 |
article | |
BibTeX:
@article{brito_alise_2022, author = {Brito, Alderlene Pimentel de and Silva, Nayandra Carvalho da and Tomasella, Javier and Ferreira, Sávio José Filgueiras and Monteiro, Maria Terezinha Ferreira}, title = {Análise do índice de Anomalia de Chuva e Tendência de Precipitação para Estações Pluviométricas na Amazônia Central.}, journal = {Revista Brasileira de Meteorologia}, year = {2022}, volume = {37} } |
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Brito, N.L.R., Fambri, L.S., Ruezzene, C.B., Aguiar Renata Gonçalves ., A.C.C. and Andrade | Aplicação do produto de evapotranspiração do MODIS para uma área de pastagem na Amazônia ocidental [BibTeX] |
2018 | Ciência e Natura Vol. 40, pp. 162-167 |
article | |
BibTeX:
@article{brito_aplicacao_2018, author = {Brito, Nara L R ; Fambri, L. S. ; Ruezzene, C. B. ; Aguiar, Renata Gonçalves ., A. C. C. ; Andrade}, title = {Aplicação do produto de evapotranspiração do MODIS para uma área de pastagem na Amazônia ocidental}, journal = {Ciência e Natura}, year = {2018}, volume = {40}, pages = {162--167} } |
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Brienen, R.J.W., Phillips, O.L., Feldpausch, T.R., Gloor, E., Baker, T.R., Lloyd, J., Lopez-Gonzalez, G., Monteagudo-Mendoza, A., Malhi, Y., Lewis, S.L., Vasquez, R., Martinez, M., Alexiades, E. and al. , e. | Signs of saturation in the tropical carbon sink [BibTeX] |
2015 | Nature Vol. 519, pp. 344-348 |
article | DOI |
BibTeX:
@article{brienen_signs_2015, author = {Brienen, R. J. W. and Phillips, O. L. and Feldpausch, T. R. and Gloor, E. and Baker, T. R. and Lloyd, J. and Lopez-Gonzalez, G. and Monteagudo-Mendoza, A. and Malhi, Y. and Lewis, S. L. and Vasquez, R. and Martinez, M. and Alexiades, E. and al., et}, title = {Signs of saturation in the tropical carbon sink}, journal = {Nature}, year = {2015}, volume = {519}, pages = {344--348}, doi = {https://doi.org/10.1038/nature14283} } |
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Bresolin, J.D., Bustamante, M.M.C., Krueger, R.H., Silva, M.R.S.S. and Perez, K.S. | Structure and composition of bacterial and fungal community in soil under soybean monoculture in the brazilian cerrado | 2010 | Brazilian Journal of Microbiology Vol. 41(2), pp. 391-403 |
article | DOI URL |
Abstract: Soybean is the most important oilseed cultivated in the world and Brazil is the second major producer. Expansion of soybean cultivation has direct and indirect impacts on natural habitats of high conservation value, such as the Brazilian savannas (Cerrado). In addition to deforestation, land conversion includes the use of fertilizers and pesticides and can lead to changes in the soil microbial communities. This study evaluated the soil bacterial and fungal communities and the microbial biomass C in a native Cerrado and in a similar no-tillage soybean monoculture area using PCR-DGGE and sequencing of bands. Compared to the native area, microbial biomass C was lower in the soybean area and cluster analysis indicated that the structure of soil microbial communities differed. 16S and 18S rDNA dendrograms analysis did not show differences between row and inter-row samples, but microbial biomass C values were higher in inter-rows during soybean fructification and harvest. The study pointed to different responses and alterations in bacterial and fungal communities due to soil cover changes (fallow x growth period) and crop development. These changes might be related to differences in the pattern of root exudates affecting the soil microbial community. Among the bands chosen for sequencing there was a predominance of actinobacteria, gamma-proteobacteria and ascomycetous divisions. Even under no-tillage management methods, the soil microbial community was affected due to changes in the soil cover and crop development, hence warning of the impacts caused by changes in land use. | |||||
BibTeX:
@article{bresolin_structure_2010, author = {Bresolin, J. D. and Bustamante, M. M. C. and Krueger, R. H. and Silva, M. R. S. S. and Perez, K. S.}, title = {Structure and composition of bacterial and fungal community in soil under soybean monoculture in the brazilian cerrado}, journal = {Brazilian Journal of Microbiology}, year = {2010}, volume = {41}, number = {2}, pages = {391--403}, url = {://WOS:000276670600021 http://www.scielo.br/pdf/bjm/v41n2/v41n2a21.pdf}, doi = {https://doi.org/10.1590/s1517-83822010000200021} } |
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Brazão, H., Sá R., L., Pinheiro, M., Costa, A.C.L., Costa, R.B., Moura, Q. and Melo, I. | Variabilidade quantitativa de população microbiana associada às condições microclimáticas observadas em solo de floresta tropical úmida [BibTeX] |
2011 | Revista Brasileira de Meteorologia Vol. 26, pp. 287 - 294 |
article | |
BibTeX:
@article{brazao_variabilidade_2011, author = {Brazão, H.R. and Sá, R., L.D.A. and Pinheiro, M.L. and Costa, A. C. L. and Costa, R. B. and Moura, Q.L. and Melo, I.F.}, title = {Variabilidade quantitativa de população microbiana associada às condições microclimáticas observadas em solo de floresta tropical úmida}, journal = {Revista Brasileira de Meteorologia}, year = {2011}, volume = {26}, pages = {287 -- 294} } |
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Braswell, B.H., Hagen, S.C., Frolking, S.E. and Salas, W.A. | A multivariable approach for mapping sub-pixel land cover distributions using MISR and MODIS: Application in the Brazilian Amazon region | 2003 | Remote Sensing of Environment Vol. 87(2-3), pp. 243-256 |
article | DOI URL |
Abstract: Accurate mapping of land cover at continental to global scales is currently limited by our ability to exploit the spatial, temporal, and radiometric characteristics of the available satellite data. Many ecologically and biogeochemically important landscape features are spatially extensive, but occur at scales much smaller than the similar to1-km footprint of wide-swath, polar orbiting radiometers. This is especially true for land cover changes associated with human activities. Satellite instruments that offer the appropriate spatial detail have much smaller swaths and longer repeat times, resulting in compositing intervals that are too large to resolve the time scales of these changes. In addition, the cost and effort associated with acquisition and processing of high-resolution data for large areas is often prohibitive. Methods for taking advantage of information contained in multiple-scale observations by combining data from high-resolution and moderate resolution sensors are thus of great current interest. In this paper, we retrieve land cover distributions in two different parts of the Brazilian Amazon region by estimating relationships between land cover fractions derived from 30-m resolution ETM+ and reflectance data from similar to1-km resolution MODIS and MISR. The scaling relationships are derived using a Bayesian-regularized artificial neural network (ANN) and compared to results using linear unmixing (LU). We explore the simultaneous use of two significant independent variables in terrestrial optical remote sensing, wavelength, and sun-sensor geometry, by combining nadir-adjusted MODIS reflectances in seven bands (VIS-SWIR) with multiangular (-71degrees to +71degrees) bidirectional reflectance data from MISR. This research was motivated by evidence from modeling and field studies demonstrating that: (a) the angular dependence of reflectance (e.g., from MISR) contains information about the structural composition of canopies that is complementary to the wavelength dependence; and (b) the SWIR portion of the spectrum (e.g., from MODIS) is sensitive to canopy moisture and shading conditions and, therefore, to the successional status of the ecosystem. This case study, using the Bayesian artificial neural network with combined MODIS-MISR data to estimate sub-pixel land cover fractions, yielded a quantitative improvement over spectral linear unmixing of single-angle, multispectral data. Our results suggest potential for broad-scale applicability despite a number of challenges related to tropical atmospheric conditions. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{braswell_multivariable_2003, author = {Braswell, B. H. and Hagen, S. C. and Frolking, S. E. and Salas, W. A.}, title = {A multivariable approach for mapping sub-pixel land cover distributions using MISR and MODIS: Application in the Brazilian Amazon region}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {2-3}, pages = {243--256}, url = {://WOS:000186447400009}, doi = {https://doi.org/10.1016/j.rse.2003.06.002} } |
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Brando, P.M., Nepstad, D.C., Davidson, E.A., Trumbore, S.E., Ray, D. and Camargo, P. | Drought effects on litterfall, wood production and belowground carbon cycling in an Amazon forest: results of a throughfall reduction experiment | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1839-1848 |
article | DOI URL |
Abstract: The Amazon Basin experiences severe droughts that may become more common in the future. Little is known of the effects of such droughts on Amazon forest productivity and carbon allocation. We tested the prediction that severe drought decreases litterfall and wood production but potentially has multiple cancelling effects on belowground production within a 7-year partial throughfall exclusion experiment. We simulated an approximately 35-41% reduction in effective rainfall from 2000 through 2004 in a 1 ha plot and compared forest response with a similar control plot. Wood production was the most sensitive component of above-ground net primary productivity (ANPP) to drought, declining by 13% the first year and up to 62% thereafter. Litterfall declined only in the third year of drought, with a maximum difference of 23% below the control plot. Soil CO2 efflux and its C-14 signature showed no significant treatment response, suggesting similar amounts and sources of belowground production. ANPP was similar between plots in 2000 and declined to a low of 41% below the control plot during the subsequent treatment years, rebounding to only a 10% difference during the first post-treatment year. Live aboveground carbon declined by 32.5 Mg ha(-1) through the effects of drought on ANPP and tree mortality. Results of this unreplicated, long-term, large-scale ecosystem manipulation experiment demonstrate that multi-year severe drought can substantially reduce Amazon forest carbon stocks. | |||||
BibTeX:
@article{brando_drought_2008, author = {Brando, Paulo M. and Nepstad, Daniel C. and Davidson, Eric A. and Trumbore, Susan E. and Ray, David and Camargo, Plinio}, title = {Drought effects on litterfall, wood production and belowground carbon cycling in an Amazon forest: results of a throughfall reduction experiment}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1839--1848}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500016 http://rstb.royalsocietypublishing.org/content/363/1498/1839.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0031} } |
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Brando, P.M., Nepstad, D.C., Balch, J.K., Bolker, B., Christman, M.C., Coe, M. and Putz, F.E. | Fire-induced tree mortality in a neotropical forest: the roles of bark traits, tree size, wood density and fire behavior | 2012 | Global Change Biology Vol. 18(2), pp. 630-641 |
article | DOI URL |
Abstract: Large-scale wildfires are expected to accelerate forest dieback in Amazonia, but the fire vulnerability of tree species remains uncertain, in part due to the lack of studies relating fire-induced mortality to both fire behavior and plant traits. To address this gap, we established two sets of experiments in southern Amazonia. First, we tested which bark traits best predict heat transfer rates (R) through bark during experimental bole heating. Second, using data from a large-scale fire experiment, we tested the effects of tree wood density (WD), size, and estimated R (inverse of cambium insulation) on tree mortality after one to five fires. In the first experiment, bark thickness explained 82% of the variance in R, while the presence of water in the bark reduced the difference in temperature between the heat source and the vascular cambium, perhaps because of high latent heat of vaporization. This novel finding provides an important insight for improving mechanistic models of fire-induced cambium damage from tropical to temperate regions. In the second experiment, tree mortality increased with increasing fire intensity (i.e. as indicated by bark char height on tree boles), which was higher along the forest edge, during the 2007 drought, and when the fire return interval was 3 years instead of one. Contrary to other tropical studies, the relationship between mortality and fire intensity was strongest in the year following the fires, but continued for 3 years afterwards. Tree mortality was low (=20%) for thick-barked individuals (=18 mm) subjected to medium-intensity fires, and significantly decreased as a function of increasing tree diameter, height and wood density. Hence, fire-induced tree mortality was influenced not only by cambium insulation but also by other traits that reduce the indirect effects of fire. These results can be used to improve assessments of fire vulnerability of tropical forests. | |||||
BibTeX:
@article{brando_fire-induced_2012, author = {Brando, Paulo M. and Nepstad, Daniel C. and Balch, Jennifer K. and Bolker, Benjamin and Christman, Mary C. and Coe, Michael and Putz, Francis E.}, title = {Fire-induced tree mortality in a neotropical forest: the roles of bark traits, tree size, wood density and fire behavior}, journal = {Global Change Biology}, year = {2012}, volume = {18}, number = {2}, pages = {630--641}, url = {://WOS:000299042500020 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2011.02533.x/asset/gcb2533.pdf?v=1&t=h6hxtc9q&s=40a4c16fb682bc45cb3fda7aa6417faa910179bb}, doi = {https://doi.org/10.1111/j.1365-2486.2011.02533.x} } |
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Brando, P., Goetz, S., Baccini, A., Nepstad, D., Beck, P., Christman, M. and da Costa, A. | Seasonal and interannual variability of climate and vegetation indices across the Amazon [BibTeX] |
2010 | Proceedings of the National Academy of Sciences of the United States of America Vol. 107(33), pp. doi: 10.1073/pnas.0908741107 |
article | |
BibTeX:
@article{brando_seasonal_2010, author = {Brando, P.M. and Goetz, S.J. and Baccini, A. and Nepstad, D.C. and Beck, P.S.A. and Christman, M.C. and da Costa, A.C.L.}, title = {Seasonal and interannual variability of climate and vegetation indices across the Amazon}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2010}, volume = {107}, number = {33}, pages = {doi: 10.1073/pnas.0908741107} } |
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Brando, P., Ray, D., Nepstad, D., Cardinot, G., Curran, L. and Oliveira, R.C. | Effects of partial throughfall exclusion on the phenology of Coussarea racemosa (Rubiaceae) in an east-central Amazon rainforest | 2006 | Oecologia Vol. 150(2), pp. 181-189 |
article | DOI URL |
Abstract: Severe droughts may alter the reproductive phenology of tropical tree species, but our understanding of these effects has been hampered by confounded variation in drought, light and other factors during natural drought events. We used a large-scale experimental reduction of throughfall in an eastern-central Amazon forest to study the phenological response to drought of an abundant subcanopy tree, Coussarea racemosa. We hypothesized that drought would alter the production and the timing of reproduction, as well as the number of viable fruits. The study system comprised two 1-ha plots in the Tapajos National Forest, Para, Brazil: a dry plot where 50% of incoming precipitation (80% throughfall) was diverted from the soil during the six-month wet season beginning in January 2000, and a wet plot that received natural rainfall inputs. Fruit production of C. racemosa was quantified every 15 days using 100 litter traps (0.5 m(2)) in each plot. The production of new leaves and flowers was recorded monthly for C. racemosa individuals. Soil water, pre-dawn leaf water potential and solar radiation were measured to help interpret phenological patterns. Over the -3.5-year period (April 2000 through December 2003), total fruit production remained similar between plots, declining by 12%. In 2003, production was four times higher in both plots than in previous years. In the dry plot, fruit fall shifted 40 and 60 days later into the dry season in 2002 and 2003, respectively. Total fruit fall dry mass production was variable across the study period. Foliage and flower production coincided with peak irradiance early in the dry season until delays in flowering appeared in the dry plot in 2002 and 2003. Plant water stress, through its influence on leaf developmental processes and, perhaps, inhibition of photosynthesis, appears to have altered both the timing of fruit fall and the quality and number of seeds produced. | |||||
BibTeX:
@article{brando_effects_2006, author = {Brando, P. and Ray, D. and Nepstad, D. and Cardinot, G. and Curran, L.M. and Oliveira, R. C.}, title = {Effects of partial throughfall exclusion on the phenology of Coussarea racemosa (Rubiaceae) in an east-central Amazon rainforest}, journal = {Oecologia}, year = {2006}, volume = {150}, number = {2}, pages = {181--189}, note = {Edition: 2006/09/07}, url = {://WOS:000241400800001 http://www.springerlink.com/content/u083825l03724214/fulltext.pdf}, doi = {https://doi.org/10.1007/s00442-006-0507-z} } |
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Brandão Jr., A. and Souza Jr., C.M. | Mapping unofficial roads with Landsat images: a new tool to improve the monitoring of the Brazilian Amazon rainforest [BibTeX] |
2006 | International Journal of Remote Sensing Vol. 27(1), pp. 177-189 |
article | |
BibTeX:
@article{brandao_jr_mapping_2006, author = {Brandão Jr., A.O. and Souza Jr., C. M.}, title = {Mapping unofficial roads with Landsat images: a new tool to improve the monitoring of the Brazilian Amazon rainforest}, journal = {International Journal of Remote Sensing}, year = {2006}, volume = {27}, number = {1}, pages = {177--189} } |
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Braga, R.C., Rosenfeld, D., Weigel, R., Jurkat, T., Andreae, M.O., Wendisch, M., Pöhlker, M.L., Klimach, T., Pöschl, U., Pöhlker, C., Voigt, C., Mahnke, C., Borrmann, S., Albrecht, R.I., Molleker, S., Vila, D.A., Machado, L.A.T. and Artaxo, P. | Comparing parameterized versus measured microphysical properties of tropical convective cloud bases during the ACRIDICON–CHUVA campaign [BibTeX] |
2017 | Atmos. Chem. Phys. Vol. 17, pp. 7365-7386 |
article | DOI |
BibTeX:
@article{braga_comparing_2017, author = {Braga, Ramon Campos and Rosenfeld, Daniel and Weigel, Ralf and Jurkat, Tina and Andreae, Meinrat O. and Wendisch, Manfred and Pöhlker, Mira L. and Klimach, Thomas and Pöschl, Ulrich and Pöhlker, Christopher and Voigt, Christiane and Mahnke, Christoph and Borrmann, Stephan and Albrecht, Rachel I. and Molleker, Sergej and Vila, Daniel A. and Machado, Luiz A. T. and Artaxo, Paulo}, title = {Comparing parameterized versus measured microphysical properties of tropical convective cloud bases during the ACRIDICON–CHUVA campaign}, journal = {Atmos. Chem. Phys.}, year = {2017}, volume = {17}, pages = {7365--7386}, doi = {https://doi.org/10.5194/acp-2016-872} } |
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Braga, R.C., Ervens, B., Rosenfeld, D., Andreae, M.O., Förster, J.D., Fütterer, D., Hernández Pardo, L., Holanda, B.A., Jurkat-Witschas, T., Krüger, O.O., Lauer, O., Machado, L.A.T., Pöhlker, C., Sauer, D., Voigt, C., Walser, A., Wendisch, M., Pöschl, U. and Pöhlker, M.L. | Cloud droplet formation at the base of tropical convective clouds: closure between modeling and measurement results of ACRIDICON–CHUVA [BibTeX] |
2021 | Atmos. Chem. Phys. Vol. 21(23), pp. 17513-17528 |
article | DOI URL |
BibTeX:
@article{braga_cloud_2021, author = {Braga, R. C. and Ervens, B. and Rosenfeld, D. and Andreae, M. O. and Förster, J. D. and Fütterer, D. and Hernández Pardo, L. and Holanda, B. A. and Jurkat-Witschas, T. and Krüger, O. O. and Lauer, O. and Machado, L. A. T. and Pöhlker, C. and Sauer, D. and Voigt, C. and Walser, A. and Wendisch, M. and Pöschl, U. and Pöhlker, M. L.}, title = {Cloud droplet formation at the base of tropical convective clouds: closure between modeling and measurement results of ACRIDICON–CHUVA}, journal = {Atmos. Chem. Phys.}, year = {2021}, volume = {21}, number = {23}, pages = {17513--17528}, url = {https://acp.copernicus.org/articles/21/17513/2021/}, doi = {https://doi.org/10.5194/acp-21-17513-2021} } |
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Bradley, A.V., Gerard, F.F., Barbier, N., Weedon, G.P., Anderson, L.O., Huntingford, C., Aragao, L.E.O.C., Zelazowski, P. and Arai, E. | Relationships between phenology, radiation and precipitation in the Amazon region | 2011 | Global Change Biology Vol. 17(6), pp. 2245-2260 |
article | DOI URL |
Abstract: In tropical areas, Dynamic Global Vegetation Models (DGVMs) still have deficiencies in simulating the timing of vegetation phenology. To start addressing this problem, standard Fourier-based methods are applied to aerosol screened monthly remotely sensed phenology time series (Enhanced Vegetation Index, EVI) and two major driving factors of phenology: solar radiation and precipitation (for March 2000 through December 2006 over northern South America). At 1 x 1 km scale using, power (or variance) spectra on good quality aerosol screened time series, annual cycles in EVI are detected across 58.24% of the study area, the strongest (largest amplitude) occurring in the savanna. Terra Firme forest have weak but significant annual cycles in comparison with savannas because of the heterogeneity of vegetation and nonsynchronous phenological events within 1 x 1 km scale pixels. Significant annual cycles for radiation and precipitation account for 86% and 90% of the region, respectively, with different spatial patterns to phenology. Cross-spectral analysis was used to compare separately radiation with phenology/EVI, precipitation with phenology/EVI and radiation with precipitation. Overall the majority of the Terra Firme forest appears to have radiation as the driver of phenology (either radiation is in phase or leading phenology/EVI at the annual scale). These results are in agreement with previous research, although in Acre, central and eastern Peru and northern Bolivia there is a coexistence of 'in phase' precipitation over Terra Firme forest. In contrast in most areas of savanna precipitation appears to be a driver and savanna areas experiencing an inverse (antiphase) relationship between radiation and phenology is consistent with inhibited grassland growth due to soil moisture limitation. The resulting maps provide a better spatial understanding of phenology-driver relationships offering a bench mark to parameterize ecological models. | |||||
BibTeX:
@article{bradley_relationships_2011, author = {Bradley, Andrew V. and Gerard, France F. and Barbier, Nicolas and Weedon, Graham P. and Anderson, Liana O. and Huntingford, Chris and Aragao, Luiz E. O. C. and Zelazowski, Przemyslaw and Arai, Egidio}, title = {Relationships between phenology, radiation and precipitation in the Amazon region}, journal = {Global Change Biology}, year = {2011}, volume = {17}, number = {6}, pages = {2245--2260}, url = {://WOS:000289641400018 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2011.02405.x/asset/j.1365-2486.2011.02405.x.pdf?v=1&t=h6hxsvwe&s=287440d32b6cab2e523d38cda058115bc01de405}, doi = {https://doi.org/10.1111/j.1365-2486.2011.02405.x} } |
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Boyd, E. | Navigating Amazonia under uncertainty: past, present and future environmental governance | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1911-1916 |
article | DOI URL |
Abstract: One of the major environmental challenges of the twenty-first century is the continued rapid deforestation of Amazonia. The 2005 dieback crisis emphasizes the unprecedented challenges facing Brazil. The examination of past and present institutions for ecosystem management, in Amazonia, shows structural barriers across public, private and community arrangements. The adaptive governance concept helps to understand why these institutions are failing to deliver sustainable futures. In looking forward, it is encouraging to see that important networks of knowledge and a number of novel initiatives are emerging in Brazil. These new arrangements are novel in the way that they seem to be adaptive and navigate structures in the hope of overcoming insurmountable drivers of deforestation. | |||||
BibTeX:
@article{boyd_navigating_2008, author = {Boyd, Emily}, title = {Navigating Amazonia under uncertainty: past, present and future environmental governance}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1911--1916}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500025 http://rstb.royalsocietypublishing.org/content/363/1498/1911.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0023} } |
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Bowman, M.S., Soares-Filho, B.S., Merry, F.D., Nepstad, D.C., Rodrigues, H. and Almeida, O.T. | Persistence of cattle ranching in the Brazilian Amazon: A spatial analysis of the rationale for beef production | 2012 | Land Use Policy Vol. 29(3), pp. 558-568 |
article | DOI URL |
Abstract: Fed by demand for beef within Brazil and in global markets, the Brazilian herd grew from 147 million head of cattle in 1990 to 200 million in 2007. Eighty-three percent of this expansion occurred in the Amazon and this trend is expected to continue as the industry bounces back from a recent agricultural downturn. Intensification of the cattle industry has been suggested as one way to reduce pressure on forest margins and spare land for soybean or sugarcane production, and is the cornerstone of Brazil's plan for mitigation of greenhouse gas emissions. To this end, federal credit programs and research and development activities in Brazil are aligning to support intensification goals, but there is no guarantee that this push for intensification will decrease the demand for land at the forest margin and as result curb CO2 emissions from deforestation. In this paper we use a spatially explicit rent model which incorporates the local effects of biophysical characteristics, infrastructure, land prices, and distance to markets and slaughterhouses to calculate 30-year Net Present Values (NPVs) of extensive cattle ranching across the Brazilian Amazon. We use the model to ask where extensive ranching is profitable and how land acquisition affects profitability. We estimate that between 17% and 80% of land in the Amazon would have moderate to high NPVs when ranched extensively if it were settled, i.e. if the rancher does not buy the land but acquires it through land grabbing. In addition, we estimate that between 9% and 13% of land in the Amazon is vulnerable to speculation (i.e. areas with positive NPVs only if land is settled and not purchased), which suggests that land speculation is an important driver of extensive ranching profitability, and may continue to be in the future. These results suggest that pro-intensification policies such as credit provision for improved pasture management and investment in more intensive production systems must be accompanied by implementation and enforcement of policies that alter the incentives to clear forest for pasture, discourage land speculation, and increase accountability for land management practices if intensification of the cattle sector is to deter new deforestation and displace production from low-yield, extensive cattle production systems in frontier regions of the Brazilian Amazon. (C) 2011 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{bowman_persistence_2012, author = {Bowman, Maria S. and Soares-Filho, Britaldo S. and Merry, Frank D. and Nepstad, Daniel C. and Rodrigues, Hermann and Almeida, Oriana T.}, title = {Persistence of cattle ranching in the Brazilian Amazon: A spatial analysis of the rationale for beef production}, journal = {Land Use Policy}, year = {2012}, volume = {29}, number = {3}, pages = {558--568}, url = {://WOS:000300745800009}, doi = {https://doi.org/10.1016/j.landusepol.2011.09.009} } |
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Bowman, M., Amacher, G. and Merry, F. | Fire use and prevention by traditional households in the Brazilian Amazon | 2008 | Ecological Economics Vol. 67(1), pp. 117-130 |
article | DOI URL |
Abstract: Fire is an important land management tool for smallholders in the Brazilian Amazon. However, when fires are not properly controlled they can give rise to large-scale wildfires that threaten forests, agricultural plantations, and settlement areas. We use data from a survey of 220 households to examine fire prevention and the scale of fire prevention and burning activities among traditional subsistence households in the Tapajos National Forest in Para, Brazil. We find that in traditional households, economic variables such as the opportunity cost of household time, market conditions, and the hiring wage are important predictors of these decisions, as is household reliance on standing forest resources for non-timber products. Our results confirm that traditional households actively engage in fire prevention, and suggest that fire prevention is motivated by a desire to protect agricultural plantations as well as standing forest reserves. The results suggest that increased income, improved infrastructure, and improved access to markets for labor and agricultural goods will encourage fire prevention among smallholders in communities with education and planning programs. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{bowman_fire_2008, author = {Bowman, M.S. and Amacher, G.S. and Merry, F.D.}, title = {Fire use and prevention by traditional households in the Brazilian Amazon}, journal = {Ecological Economics}, year = {2008}, volume = {67}, number = {1}, pages = {117--130}, url = {://WOS:000259660800012}, doi = {https://doi.org/10.1016/j.ecolecon.2007.12.003} } |
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Bowman, D.M.J.S., Balch, J.K., Artaxo, P., Bond, W.J., Carlson, J.M., Cochrane, M.A., D'Antonio, C.M., DeFries, R.S., Doyle, J.C., Harrison, S.P., Johnston, F.H., Keeley, J.E., Krawchuk, M.A., Kull, C.A., Marston, J.B., Moritz, M.A., Prentice, I.C., Roos, C.I., Scott, A.C., Swetnam, T.W., van der Werf, G.R. and Pyne, S.J. | Fire in the Earth System | 2009 | Science Vol. 324(5926), pp. 481-484 |
article | DOI URL |
Abstract: Fire is a worldwide phenomenon that appears in the geological record soon after the appearance of terrestrial plants. Fire influences global ecosystem patterns and processes, including vegetation distribution and structure, the carbon cycle, and climate. Although humans and fire have always coexisted, our capacity to manage fire remains imperfect and may become more difficult in the future as climate change alters fire regimes. This risk is difficult to assess, however, because fires are still poorly represented in global models. Here, we discuss some of the most important issues involved in developing a better understanding of the role of fire in the Earth system. | |||||
BibTeX:
@article{bowman_fire_2009, author = {Bowman, David M. J. S. and Balch, Jennifer K. and Artaxo, Paulo and Bond, William J. and Carlson, Jean M. and Cochrane, Mark A. and D'Antonio, Carla M. and DeFries, Ruth S. and Doyle, John C. and Harrison, Sandy P. and Johnston, Fay H. and Keeley, Jon E. and Krawchuk, Meg A. and Kull, Christian A. and Marston, J. Brad and Moritz, Max A. and Prentice, I. Colin and Roos, Christopher I. and Scott, Andrew C. and Swetnam, Thomas W. and van der Werf, Guido R. and Pyne, Stephen J.}, title = {Fire in the Earth System}, journal = {Science}, year = {2009}, volume = {324}, number = {5926}, pages = {481--484}, note = {Edition: 2009/04/25}, url = {://WOS:000265411200037 http://www.sciencemag.org/content/324/5926/481}, doi = {https://doi.org/10.1126/science.1163886} } |
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Bowman, DMJS, Gloor, E, Phillips OL & Prior, LD. and Brienen, RJW | Detecting trends in tree growth: not so simple [BibTeX] |
2013 | Trends in Plant Science Vol. 18(1), pp. 11-17 |
article | DOI |
BibTeX:
@article{bowman_dmjs_detecting_2013, author = {Bowman DMJS, Gloor E, Phillips OL & Prior LD., Brienen RJW}, title = {Detecting trends in tree growth: not so simple}, journal = {Trends in Plant Science}, year = {2013}, volume = {18}, number = {1}, pages = {11--17}, doi = {https://doi.org/10.1016/j.tplants.2012.08.005} } |
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Bowman, D., Balch, J., Artaxo, P., Bond, W., Cochrane, M., D'Antonio, C., DeFries, R., Johnston, F., Keeley, J., Krawchuk, M., Kull, C., Mack, M., Moritz, M., Pyne, S., Roos, C., Scott, A., Sodhi, N. and Swetnam, T. | The human dimension of fire regimes on Earth [BibTeX] |
2011 | Journal of Biogeography Vol. 38(12), pp. 2223-2236 |
article | DOI URL |
BibTeX:
@article{bowman_human_2011, author = {Bowman, D. and Balch, J. and Artaxo, P. and Bond, W. and Cochrane, M. and D'Antonio, C. and DeFries, R. and Johnston, F. and Keeley, J. and Krawchuk, M. and Kull, C. and Mack, M. and Moritz, M. and Pyne, S. and Roos, C. and Scott, A. and Sodhi, N. and Swetnam, T.}, title = {The human dimension of fire regimes on Earth}, journal = {Journal of Biogeography}, year = {2011}, volume = {38}, number = {12}, pages = {2223--2236}, url = {http://onlinelibrary.wiley.com/store/10.1111/j.1365-2699.2011.02595.x/asset/j.1365-2699.2011.02595.x.pdf?v=1&t=h6hxsdwh&s=e89e852eccc324a8998e970a4bb6a95437d813c8}, doi = {https://doi.org/10.1111/j.1365-2699.2011.02595.x} } |
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Bourtsoukidis, B., Yanez-Serrano, T., A. M., H., Diamantopoulos, H., Catao, E., Ashworth, E., Pozzer, K., Quesada, A., C. A., M., D. L., S., Araujo, M., Brito, A., Artaxo, J., Kesselmeier, P., Lelieveld, J., Williams, J. and E., J. | Strong sesquiterpene emissions from Amazonian soils [BibTeX] |
2018 | Nature Communications Vol. 9, pp. 2226 |
article | DOI |
BibTeX:
@article{bourtsoukidis_strong_2018, author = {Bourtsoukidis, Behrendt, T., Yanez-Serrano, A. M., Hellen, H., Diamantopoulos, E., Catao, E., Ashworth, K., Pozzer, A., Quesada, C. A., Martins, D. L., Sa, M., Araujo, A., Brito, J., Artaxo, P., Kesselmeier, J., Lelieveld, J., Williams, J., E.}, title = {Strong sesquiterpene emissions from Amazonian soils}, journal = {Nature Communications}, year = {2018}, volume = {9}, pages = {2226}, doi = {https://doi.org/10.1038/s41467-018-04658-y} } |
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Botta, A., Ramankutty, N. and Foley, J.A. | Long-term variations of climate and carbon fluxes over the Amazon basin | 2002 | Geophysical Research Letters Vol. 29(15) |
article | DOI URL |
Abstract: [1] The Amazon basin contains some of the most productive ecosystems on the planet, yet we have little understanding of their long-term behavior. By examining historical climate records over the Amazon, we identify several modes of climatic variability-including previously undocumented long-term modes. Furthermore, using a process-based ecosystem model, we show that these variations in climate generate variations in terrestrial carbon fluxes on short (3-4 year), intermediate (8-9 year), and long (24-28 year) time scales. The long-term cycles in terrestrial carbon balance have not been previously suggested. Finally, we find that time-lags between productivity and decomposition enhance the short-term variations in net carbon balance, while slightly dampening the long-term variations. Given the worldwide attention on terrestrial carbon cycling, and the potential for "carbon sinks'', we suggest that an improved understanding of long-term climatic and ecosystem processes is crucial. Other regions should be examined for potential long-term carbon cycle variations. | |||||
BibTeX:
@article{botta_long-term_2002, author = {Botta, A. and Ramankutty, N. and Foley, J. A.}, title = {Long-term variations of climate and carbon fluxes over the Amazon basin}, journal = {Geophysical Research Letters}, year = {2002}, volume = {29}, number = {15}, url = {://WOS:000178888000044 http://www.agu.org/pubs/crossref/2002/2001GL013607.shtml}, doi = {https://doi.org/10.1029/2001gl013607} } |
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Botta, A. and Foley, J.A. | Effects of climate variability and disturbances on the Amazonian terrestrial ecosystems dynamics | 2002 | Global Biogeochemical Cycles Vol. 16(4) |
article | DOI URL |
Abstract: This article examines how climate variability and ecological disturbances affect ecosystem composition and functioning in the Amazon region. We use a terrestrial ecosystem model, IBIS, and vary the treatment of climate (using either long-term average climate, or actual historical variations in climate) and disturbances (with uniform disturbance rates applied through the region). Interannual climate variability and frequent disturbances both favor grasses over trees, causing large increases in the geographic extent of savanna in the south and east of the region. A more constant climate and less frequent disturbances both favor trees over grasses, causing forest to dominate most of the study area. While climate variability and disturbances have a major impact on ecosystem structure, we find that compensating processes between herbaceous and woody plants damp the simulated response of carbon and water fluxes. Nevertheless, the cumulative impact of these changes in vegetation structure results in significant changes in soil and vegetation carbon stocks (up to 36%). | |||||
BibTeX:
@article{botta_effects_2002, author = {Botta, A. and Foley, J. A.}, title = {Effects of climate variability and disturbances on the Amazonian terrestrial ecosystems dynamics}, journal = {Global Biogeochemical Cycles}, year = {2002}, volume = {16}, number = {4}, url = {://WOS:000180874100018 http://www.agu.org/pubs/crossref/2002/2000GB001338.shtml}, doi = {https://doi.org/10.1029/2000gb001338} } |
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Botía, S., Komiya, S., Marshall, J., Koch, T., Gałkowski, M., Lavric, J., Gomes-Alves, E., Walter, D., Fisch, G., Pinho, D.M., Nelson, B.W., Martins, G., Luijkx, I.T., Koren, G., Florentie, L., Carioca de Araújo, A., Sá, M., Andreae, M.O., Heimann, M., Peters, W. and Gerbig, C. | The CO2 record at the Amazon Tall Tower Observatory: A new opportunity to study processes on seasonal and inter-annual scales | 2022 | Global Change Biology Vol. 28(2), pp. 588-611 |
article | DOI URL |
Abstract: Abstract High-quality atmospheric CO2 measurements are sparse in Amazonia, but can provide critical insights into the spatial and temporal variability of sources and sinks of CO2. In this study, we present the first 6 years (2014–2019) of continuous, high-precision measurements of atmospheric CO2 at the Amazon Tall Tower Observatory (ATTO, 2.1°S, 58.9°W). After subtracting the simulated background concentrations from our observational record, we define a CO2 regional signal () that has a marked seasonal cycle with an amplitude of about 4 ppm. At both seasonal and inter-annual scales, we find differences in phase between and the local eddy covariance net ecosystem exchange (EC-NEE), which is interpreted as an indicator of a decoupling between local and non-local drivers of . In addition, we present how the 2015–2016 El Niño-induced drought was captured by our atmospheric record as a positive 2σ anomaly in both the wet and dry season of 2016. Furthermore, we analyzed the observed seasonal cycle and inter-annual variability of together with net ecosystem exchange (NEE) using a suite of modeled flux products representing biospheric and aquatic CO2 exchange. We use both non-optimized and optimized (i.e., resulting from atmospheric inverse modeling) NEE fluxes as input in an atmospheric transport model (STILT). The observed shape and amplitude of the seasonal cycle was captured neither by the simulations using the optimized fluxes nor by those using the diagnostic Vegetation and Photosynthesis Respiration Model (VPRM). We show that including the contribution of CO2 from river evasion improves the simulated shape (not the magnitude) of the seasonal cycle when using a data-driven non-optimized NEE product (FLUXCOM). The simulated contribution from river evasion was found to be 25% of the seasonal cycle amplitude. Our study demonstrates the importance of the ATTO record to better understand the Amazon carbon cycle at various spatial and temporal scales. | |||||
BibTeX:
@article{botia_co2_2022, author = {Botía, Santiago and Komiya, Shujiro and Marshall, Julia and Koch, Thomas and Gałkowski, Michał and Lavric, Jost and Gomes-Alves, Eliane and Walter, David and Fisch, Gilberto and Pinho, Davieliton M. and Nelson, Bruce W. and Martins, Giordane and Luijkx, Ingrid T. and Koren, Gerbrand and Florentie, Liesbeth and Carioca de Araújo, Alessandro and Sá, Marta and Andreae, Meinrat O. and Heimann, Martin and Peters, Wouter and Gerbig, Christoph}, title = {The CO2 record at the Amazon Tall Tower Observatory: A new opportunity to study processes on seasonal and inter-annual scales}, journal = {Global Change Biology}, year = {2022}, volume = {28}, number = {2}, pages = {588--611}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.15905}, doi = {https://doi.org/10.1111/gcb.15905} } |
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Botía, S., Gerbig, C., Marshall, J., Lavric, J.V., Walter, D., Pöhlker, C., Holanda, B., Fisch, G., de Araújo, A.C., Sá, M.O., Teixeira, P.R., Resende, A.F., Dias-Junior, C.Q., van Asperen, H., Oliveira, P.S., Stefanello, M. and Acevedo, O.C. | Understanding nighttime methane signals at the Amazon Tall Tower Observatory (ATTO) [BibTeX] |
2020 | Atmos. Chem. Phys. Vol. 20(11), pp. 6583-6606 |
article | DOI URL |
BibTeX:
@article{botia_understanding_2020, author = {Botía, S. and Gerbig, C. and Marshall, J. and Lavric, J. V. and Walter, D. and Pöhlker, C. and Holanda, B. and Fisch, G. and de Araújo, A. C. and Sá, M. O. and Teixeira, P. R. and Resende, A. F. and Dias-Junior, C. Q. and van Asperen, H. and Oliveira, P. S. and Stefanello, M. and Acevedo, O. C.}, title = {Understanding nighttime methane signals at the Amazon Tall Tower Observatory (ATTO)}, journal = {Atmos. Chem. Phys.}, year = {2020}, volume = {20}, number = {11}, pages = {6583--6606}, url = {https://acp.copernicus.org/articles/20/6583/2020/}, doi = {https://doi.org/10.5194/acp-20-6583-2020} } |
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Borma, J., Roballo, S., Cuartas, L., Rodriguez, D., Marengo, J., Nobre C.A., L. and Tomasella | Impactos dos eventos extremos de seca e cheia sobre os recursos hídricos amazônicos e ações da Defesa Civil [BibTeX] |
2013 | Vol. 1ed.Secas na Amazônia, causas e consequências., pp. 305-333 |
incollection | |
BibTeX:
@incollection{nobre_impactos_2013, author = {Borma, J.; Roballo, S.T.; Cuartas, L.A.; Rodriguez, D.A.; Marengo, J.A.; Nobre, C.A., L.S.; Tomasella}, title = {Impactos dos eventos extremos de seca e cheia sobre os recursos hídricos amazônicos e ações da Defesa Civil}, booktitle = {Secas na Amazônia, causas e consequências.}, publisher = {Oficina de Textos}, year = {2013}, volume = {1ed.}, pages = {305--333} } |
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Borma, L.S., da Rocha, H.R., Cabral, O.M., von Randow, C., Collicchio, E., Kurzatkowski, D., Brugger, P.J., Freitas, H., Tannus, R., Oliveira, L., Renno, C.D. and Artaxo, P. | Atmosphere and hydrological controls of the evapotranspiration over a floodplain forest in the Bananal Island region, Amazonia | 2009 | Journal of Geophysical Research-Biogeosciences Vol. 114 |
article | DOI URL |
Abstract: This article discusses seasonal and interannual variations of the evapotranspiration (ET) rates in Bananal Island floodplain, Brazil. Measurements included ET and sensible heat flux using the eddy covariance method, atmospheric forcings (net radiation, Rn, vapor pressure deficit, VPD, wind speed and air temperature), soil moisture profiles, groundwater level and flood height, taken from November 2003 to December 2006. For the hydrological years (October-September) of 2003/2004, 2004/2005 and 2005/2006, the accumulated precipitation was 1692, 1471, 1914 mm and the accumulated ET was 1361, 1318 and 1317 mm, respectively. Seasonal analyses indicated that ET decreased in the dry season (average 3.7 mm day(-1)), despite the simultaneous increase in Rn, air temperature and VPD. The increase of ET in the wet season and particularly in the flood period (average 4.1 mm day(-1)) showed that the free water surface evaporation strongly influenced the energy exchange. Soil moisture, which was substantially depleted during the dry season, and adaptative vegetation mechanisms such as leaf senescence contributed to limit the dry season ET. Strong drainage within permeable sandy soils helped to explain the soil moisture depletion. These results suggest that the Bananal flooding area shows a different pattern in relation to the upland Amazon forests, being more similar to the savanna strictu senso areas in central Brazil. For example, seasonal ET variation was not in phase with Rn; the wet season ET was higher than the dry season ET; and the system stored only a tiny memory of the flooding period, being sensitive to extended drought periods. | |||||
BibTeX:
@article{borma_atmosphere_2009, author = {Borma, L. S. and da Rocha, H. R. and Cabral, O. M. and von Randow, C. and Collicchio, E. and Kurzatkowski, D. and Brugger, P. J. and Freitas, H. and Tannus, R. and Oliveira, L. and Renno, C. D. and Artaxo, P.}, title = {Atmosphere and hydrological controls of the evapotranspiration over a floodplain forest in the Bananal Island region, Amazonia}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2009}, volume = {114}, url = {://WOS:000262749600001 http://www.agu.org/pubs/crossref/2009/2007JG000641.shtml}, doi = {https://doi.org/10.1029/2007jg000641} } |
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Bolzan, M.J.A. and Vieira, P.C. | Wavelet analysis of the wind velocity and temperature variability in the Amazon forest | 2006 | Brazilian Journal of Physics Vol. 36(4A), pp. 1217-1222 |
article | URL |
Abstract: We studied the turbulent interactions among vertical wind velocity and temperature time-series measured in the Amazonian forest, during the wet season campaign of Large Biophere-Atmosphere Experiment in Amazonia (LBA) in 1999. The approach is based on the estimation of the correlation coefficient between the different scales in turbulent fields and Cross Wavelet Power (XWP). The results suggest that the correlations among scales of the vertical wind velocity are due to the Coherent Structures (CS), a large scale signature in the thermal profile. These coherent structures, kind of ramps, promoted an increase in the interaction among both variables, vertical wind velocity and temperature, and also depends on the atmospheric stability conditions. Furthermore, these coherent structures may explain the higher values of the correlation coefficient found in the large scales during the diurnal period compared with the nocturnal period, for the vertical wind velocity. | |||||
BibTeX:
@article{bolzan_wavelet_2006, author = {Bolzan, M. J. A. and Vieira, P. C.}, title = {Wavelet analysis of the wind velocity and temperature variability in the Amazon forest}, journal = {Brazilian Journal of Physics}, year = {2006}, volume = {36}, number = {4A}, pages = {1217--1222}, url = {://000243070400018} } |
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Bolzan, M.J.A., Ramos, F.M., Sa, L.D.A., Neto, C.R. and Rosa, R.R. | Analysis of fine-scale canopy turbulence within and above an Amazon forest using Tsallis' generalized thermostatistics | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: We analyzed the probability density function (PDF) of velocity and temperature differences in the canopy sublayer of Amazonia based on Tsallis' generalized thermostatistics theory. We show that such a theory provides an accurate framework for modeling the statistical behavior of the inertial subrange above and below the canopy. For this, we compared the experimental PDFs with the theoretically predicted ones. The data were measured during the wet season of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), which was carried out during the months of January-March 1999 in the southwestern part of Amazonia region. Measurements were made simultaneously at different heights in a 60 m micrometeorological tower located in the Biological Reserve of Jaru (10degrees04'S, 61degrees56'W), Brazil. The fast response wind speed measurements, sampled at 60 Hz rate, were made using three-dimensional sonic anemometers at the heights of 66 m (above the canopy) and 21 m (below the canopy). The results showed good agreement between experimental data measured above the canopy forest and Tsallis' generalized thermostatistics theory. For below canopy data, the agreement between experimental and theoretical PDFs was fairly good, but some distortion was observed. This is probably due to some peculiar characteristics of turbulent momentum transfer process inside the forest crown. Discussion is presented to explain these results. Conclusions regarding the absence of "universal scaling" in the inertial subrange are also presented in the context of the entropic parameter of Tsallis' theory. | |||||
BibTeX:
@article{bolzan_analysis_2002, author = {Bolzan, M. J. A. and Ramos, F. M. and Sa, L. D. A. and Neto, C. R. and Rosa, R. R.}, title = {Analysis of fine-scale canopy turbulence within and above an Amazon forest using Tsallis' generalized thermostatistics}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200019 http://www.agu.org/journals/jd/jd0217/2001JD000378/2001JD000378.pdf}, doi = {https://doi.org/10.1029/2001jd000378} } |
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Boltz, F., Carter, D.R., Holmes, T.P. and Pereira, R. | Financial returns under uncertainty for conventional and reduced-impact logging in permanent production forests of the Brazilian Amazon | 2001 | Ecological Economics Vol. 39(3), pp. 387-398 |
article | DOI URL |
Abstract: Reduced-impact logging (RIL) techniques are designed to improve the efficiency of timber harvesting while mitigating its adverse effects on the forest ecosystem. Research on RIL in select tropical forest regions has demonstrated clear ecological benefits relative to conventional logging (CL) practices while the financial competitiveness of RIL is less conclusive. We conduct a comparative analysis of financial returns to one and two cutting-cycle logging entries for representative RIL and CL operations of the eastern Amazon. Observed variability in harvest efficiency and uncertainties of forest productivity are introduced in a stochastic simulation of future biological and financial returns to the alternative logging systems. Despite the perceived investment risks, RIL harvesting operations generate competitive or superior returns relative to CL for a wide range of discount rates due to gains in harvest efficiency and forest conservation. (C) 2001 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{boltz_financial_2001, author = {Boltz, F. and Carter, D. R. and Holmes, T. P. and Pereira, R.}, title = {Financial returns under uncertainty for conventional and reduced-impact logging in permanent production forests of the Brazilian Amazon}, journal = {Ecological Economics}, year = {2001}, volume = {39}, number = {3}, pages = {387--398}, url = {://WOS:000172871300006 http://ac.els-cdn.com/S0921800901002312/1-s2.0-S0921800901002312-main.pdf?_tid=7751be94-03f2-11e2-8de4-00000aab0f01&acdnat=1348235249_c72e4244ce58dec7ebdd683831aa6bf8}, doi = {https://doi.org/10.1016/s0921-8009(01)00231-2} } |
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Boian, K., V.W.J.H., M., Saleska, W., Wofsy, S.R. and S. C., C. | Very high CO mixing ratios at a primary forest site [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 3a(21), pp. 20-28 |
article | |
BibTeX:
@article{boian_very_2006, author = {Boian, Kirchhoff, V.W.J.H., Munger, W., Saleska, S.R., Wofsy, S. C., C.}, title = {Very high CO mixing ratios at a primary forest site}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {3a}, number = {21}, pages = {20--28} } |
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Bohlman, S., Laurance, W., Laurance, S., Nascimento, H.M., Fearnside, P. and Ana, A. | Importance of soils, topography and geographic distance in structuring central Amazonian tree communities | 2008 | Journal of Vegetation Science Vol. 19(6), pp. 863-874 |
article | DOI URL |
Abstract: Question: What is the relative contribution of geographic distance, soil and topographic variables in determining the community floristic patterns and individual tree species abundances in the nutrient-poor soils of central Amazonia? Location: Central Amazonia near Manaus, Brazil. Methods: Our analysis was based on data for 1105 tree species (textgreater= 10 cm dbh) within 40 1-ha plots over a ca. 1000-km(2) area. Slope and 26 soil-surface parameters were measured for each plot. A main soil- fertility gradient (encompassing soil texture, cation content, nitrogen and carbon) and five other uncorrelated soil and topographic variables were used as potential predictors of plant-community composition. Mantel tests and multiple regressions on distance matrices were used to detect relationships at the community level, and ordinary least square (OLS) and conditional autoregressive (CAR) models were used to detect relationships for individual species abundances. Results: Floristic similarity declined rapidly with distance over small spatial scales (0-5 km), but remained constant (ca. 44%) over distances of 5 to 30 km, which indicates lower beta diversity than in western Amazonian forests. Distance explained 1/3 to 1/2 more variance in floristics measures than environmental variables. Community composition was most strongly related to the main soil- fertility gradient and C:N ratio. The main fertility gradient and pH had the greatest impact of species abundances. About 30% of individual tree species were significantly related to one or more soil/topographic parameters. Conclusions: Geographic distance and the main fertility gradient are the best predictors of community floristic composition, but other soil variables, particularly C: N ratio, pH, and slope, have strong relationships with a significant portion of the tree community. |
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BibTeX:
@article{bohlman_importance_2008, author = {Bohlman, S.A. and Laurance, W.F. and Laurance, S.G. and Nascimento, H.E. M. and Fearnside, P.M. and Ana, A.}, title = {Importance of soils, topography and geographic distance in structuring central Amazonian tree communities}, journal = {Journal of Vegetation Science}, year = {2008}, volume = {19}, number = {6}, pages = {863--874}, url = {://WOS:000264001900014 http://onlinelibrary.wiley.com/store/10.3170/2008-8-18463/asset/2008-8-18463.pdf?v=1&t=h6hxrsdg&s=24744484b97371a3aedf9a86998393107c761f28}, doi = {https://doi.org/10.3170/2008-8-18463} } |
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Boers, N., Marwan, N., Barbosa, H.M.J. and Kurths, J. | A deforestation-induced tipping point for the South American monsoon system [BibTeX] |
2017 | Nature Scientific Reports Vol. 7, pp. 41489 |
article | DOI |
BibTeX:
@article{boers_deforestation-induced_2017, author = {Boers, Niklas and Marwan, Norbert and Barbosa, Henrique M. J. and Kurths, Jürgen}, title = {A deforestation-induced tipping point for the South American monsoon system}, journal = {Nature Scientific Reports}, year = {2017}, volume = {7}, pages = {41489}, doi = {https://doi.org/10.1038/srep41489} } |
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Boers, N. and al. , e. | Prediction of Extreme Floods in the Eastern Central Andes: A Complex Networks Approach [BibTeX] |
2014 | Nature Communications | article | |
BibTeX:
@article{boers_prediction_2014, author = {Boers, N. and al., et}, title = {Prediction of Extreme Floods in the Eastern Central Andes: A Complex Networks Approach}, journal = {Nature Communications}, year = {2014} } |
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Bleich, M., Mortati, A., André T., M. and Piedade | Autochthonous primary production in Southern Amazon headwater streams: Novel indicators of altered environmental integrity [BibTeX] |
2015 | Ecological Indicators Vol. 53, pp. 154-161 |
article | |
BibTeX:
@article{bleich_autochthonous_2015, author = {Bleich, MTF; Mortati, AF; André, T., ME; Piedade}, title = {Autochthonous primary production in Southern Amazon headwater streams: Novel indicators of altered environmental integrity}, journal = {Ecological Indicators}, year = {2015}, volume = {53}, pages = {154--161} } |
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Bleich, M., Knopki, P., Castro, N., Jati, S., Sousa RN., M. and Piedade | Influência das condições do habitat sobre a estrutura de herbáceas aquáticas na região do Lago Catalão, Manaus, AM [BibTeX] |
2014 | Acta Amazonica Vol. 44, pp. 481-490 |
article | |
BibTeX:
@article{bleich_influencia_2014, author = {Bleich, MTF; Knopki, PB; Castro, NGD; Jati, SR; Sousa, RN., ME; Piedade}, title = {Influência das condições do habitat sobre a estrutura de herbáceas aquáticas na região do Lago Catalão, Manaus, AM}, journal = {Acta Amazonica}, year = {2014}, volume = {44}, pages = {481--490} } |
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Bleich, A., André, T., Piedade MTF., M. and Mortati | Structural Dynamics of Pristine Headwater Streams from Southern Brazilian Amazon [BibTeX] |
2015 | Rivers Research and Applications | article | |
BibTeX:
@article{bleich_structural_2015, author = {Bleich, AF; André, T; Piedade, MTF., ME; Mortati}, title = {Structural Dynamics of Pristine Headwater Streams from Southern Brazilian Amazon}, journal = {Rivers Research and Applications}, year = {2015} } |
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Bleich, A., Andre, T., Piedade MTF., M. and Mortati | Riparian deforestation affects the structural dynamics of headwater streams in Southern Brazilian Amazonia [BibTeX] |
2014 | Tropical Conservation Science Vol. 4, pp. 657-676 |
article | |
BibTeX:
@article{bleich_riparian_2014, author = {Bleich, AF; Andre, T; Piedade, MTF., ME; Mortati}, title = {Riparian deforestation affects the structural dynamics of headwater streams in Southern Brazilian Amazonia}, journal = {Tropical Conservation Science}, year = {2014}, volume = {4}, pages = {657--676} } |
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Blazso, M., Janitsek, S., Gelencser, A., Artaxo, P., Graham, B. and Andreae, M.O. | Study of tropical organic aerosol by thermally assisted alkylation-gas chromatography mass spectrometry | 2003 | Journal of Analytical and Applied Pyrolysis Vol. 68-9, pp. 351-369 |
article | DOI URL |
Abstract: Fine (textless 2.6 mum) and size-segregated aerosol samples collected at a tropical pasture site (Rondonia, Brazil) under various conditions have been analysed by thermally assisted hydrolysis and alkylation, coupled to GUMS. Fatty acids, alkadioic acids, hydroxybenzoic acids, levoglucosan, and other compounds of polysaccharide origin have been identified as their methyl ester and ether derivatives among the products of thermally assisted methylation. The identity of the characteristic hydrolysed fragments and soluble components has been confirmed by butylation and silylation as well. To improve available chemical information, this analytical method has also been combined with a thermal pre-treatment. Seasonal variation of size-resolved distribution of the characteristic fragments of thermally assisted hydrolysis and methylation (THM) in the atmospheric aerosol is shown. Although the results presented in this paper are preliminary and based on a limited number of aerosol samples, they clearly demonstrate the sensitivity and potential of thermally assisted alkylation-GUMS to provide unique chemical information on the bulk of organic matter in tropospheric aerosol to facilitate their source apportionment. (C) 2003 Elsevier Science B.V. All rights reserved. | |||||
BibTeX:
@article{blazso_study_2003, author = {Blazso, M. and Janitsek, S. and Gelencser, A. and Artaxo, P. and Graham, B. and Andreae, M. O.}, title = {Study of tropical organic aerosol by thermally assisted alkylation-gas chromatography mass spectrometry}, journal = {Journal of Analytical and Applied Pyrolysis}, year = {2003}, volume = {68-9}, pages = {351--369}, url = {://WOS:000184573200025}, doi = {https://doi.org/10.1016/s0165-2370(03)00082-2} } |
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Biudes, M., Vourlitis, G., Machado, N., Arruda, P.d., Neves, G., Lobo, F., Neal, C. and Nogueira, J. | Patterns of energy exchange for tropical ecosystems across a climate gradient in Mato Grosso, Brazil [BibTeX] |
2015 | Agricultural and Forest Meteorology Vol. 202, pp. 112-124 |
article | |
BibTeX:
@article{biudes_patterns_2015, author = {Biudes, M.S. and Vourlitis, G.L. and Machado, N.G. and Arruda, P.H.Z. de and Neves, G.A.R. and Lobo, F.A. and Neal, C.M.U. and Nogueira, J.S.}, title = {Patterns of energy exchange for tropical ecosystems across a climate gradient in Mato Grosso, Brazil}, journal = {Agricultural and Forest Meteorology}, year = {2015}, volume = {202}, pages = {112--124} } |
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Biudes, M. and Vourlitis, G.L. | Initial litter and soil C and N mineralization dynamics for a semi-arid scrubland exposed to experimental N deposition [BibTeX] |
2012 | Soil Science Society of America Journal Vol. 76, pp. 2068-2073 |
article | DOI |
BibTeX:
@article{biudes_initial_2012, author = {Biudes, M.S. and G.L., Vourlitis}, title = {Initial litter and soil C and N mineralization dynamics for a semi-arid scrubland exposed to experimental N deposition}, journal = {Soil Science Society of America Journal}, year = {2012}, volume = {76}, pages = {2068--2073}, doi = {https://doi.org/10.2136/sssaj2012.0101n} } |
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Biudes, J., J.H.C., N., Sanches, J.S. and M.S., L. | Estimativa do balanço de energia em cambarazal e pastagem no norte do pantanal pelo método da Razão de Bowen [BibTeX] |
2009 | Revista Brasileira de Meteorologia Vol. 24(2), pp. 135-143 |
article | |
BibTeX:
@article{biudes_estimativa_2009, author = {Biudes, Júnior, J.H.C., Nogueira, J.S., Sanches, L., M.S.}, title = {Estimativa do balanço de energia em cambarazal e pastagem no norte do pantanal pelo método da Razão de Bowen}, journal = {Revista Brasileira de Meteorologia}, year = {2009}, volume = {24}, number = {2}, pages = {135--143} } |
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Bittencourt, P.R.L., Oliveira, R.S., da Costa, A.C.L., Giles, A.L., Coughlin, I., Costa, P.B., Bartholomew, D.C., Ferreira, L.V., Vasconcelos, S.S., Barros, F.V., Junior, J.A.S., Oliveira, A.A.R., Mencuccini, M., Meir, P. and Rowland, L. | Amazonia trees have limited capacity to acclimate plant hydraulic properties in response to long-term drought | 2020 | Global Change Biology Vol. 26(6), pp. 3569-3584 |
article | DOI URL |
Abstract: Abstract The fate of tropical forests under future climate change is dependent on the capacity of their trees to adjust to drier conditions. The capacity of trees to withstand drought is likely to be determined by traits associated with their hydraulic systems. However, data on whether tropical trees can adjust hydraulic traits when experiencing drought remain rare. We measured plant hydraulic traits (e.g. hydraulic conductivity and embolism resistance) and plant hydraulic system status (e.g. leaf water potential, native embolism and safety margin) on textgreater150 trees from 12 genera (36 species) and spanning a stem size range from 14 to 68 cm diameter at breast height at the world's only long-running tropical forest drought experiment. Hydraulic traits showed no adjustment following 15 years of experimentally imposed moisture deficit. This failure to adjust resulted in these drought-stressed trees experiencing significantly lower leaf water potentials, and higher, but variable, levels of native embolism in the branches. This result suggests that hydraulic damage caused by elevated levels of embolism is likely to be one of the key drivers of drought-induced mortality following long-term soil moisture deficit. We demonstrate that some hydraulic traits changed with tree size, however, the direction and magnitude of the change was controlled by taxonomic identity. Our results suggest that Amazonian trees, both small and large, have limited capacity to acclimate their hydraulic systems to future droughts, potentially making them more at risk of drought-induced mortality. | |||||
BibTeX:
@article{bittencourt_amazonia_2020, author = {Bittencourt, Paulo R. L. and Oliveira, Rafael S. and da Costa, Antonio C. L. and Giles, Andre L. and Coughlin, Ingrid and Costa, Patricia B. and Bartholomew, David C. and Ferreira, Leandro V. and Vasconcelos, Steel S. and Barros, Fernanda V. and Junior, Joao A. S. and Oliveira, Alex A. R. and Mencuccini, Maurizio and Meir, Patrick and Rowland, Lucy}, title = {Amazonia trees have limited capacity to acclimate plant hydraulic properties in response to long-term drought}, journal = {Global Change Biology}, year = {2020}, volume = {26}, number = {6}, pages = {3569--3584}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.15040}, doi = {https://doi.org/10.1111/gcb.15040} } |
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Bispo, P.d.C., Balzter, H., Malhi, Y., Slik, J.W.F., Santos, J.R.d., Rennó, C.D., Espírito-Santo, F.D., Aragão, L.E.O.C., Ximenes, A.C. and Bispo, P.d.C. | Drivers of metacommunity structure diverge for common and rare Amazonian tree species [BibTeX] |
2017 | PLoS ONE Vol. 12(11), pp. e0188300 |
article | DOI |
BibTeX:
@article{bispo_drivers_2017, author = {Bispo, Polyanna da Conceição and Balzter, Heiko and Malhi, Yadvinder and Slik, J. W. Ferry and Santos, João Roberto dos and Rennó, Camilo Daleles and Espírito-Santo, Fernando D. and Aragão, Luiz E. O. C. and Ximenes, Arimatéa C. and Bispo, Pitágoras da Conceição}, title = {Drivers of metacommunity structure diverge for common and rare Amazonian tree species}, journal = {PLoS ONE}, year = {2017}, volume = {12}, number = {11}, pages = {e0188300}, doi = {https://doi.org/10.1371/journal.pone.0188300} } |
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Biscaro, T. and Morales, C. | Continental passive microwave-based rainfall estimation algorithm: Application to the Amazon Basin | 2008 | Journal of Applied Meteorology and Climatology Vol. 47(7), pp. 1962-1981 |
article | DOI URL |
Abstract: This paper presents a new statistical algorithm to estimate rainfall over the Amazon Basin region using the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI). The algorithm relies on empirical relationships derived for different raining-type systems between coincident measurements of surface rainfall rate and 85-GHz polarization-corrected brightness temperature as observed by the precipitation radar (PR) and TMI on board the TRMM satellite. The scheme includes rain/no-rain area delineation (screening) and system-type classification routines for rain retrieval. The algorithm is validated against independent measurements of the TRMM-PR and S-band dual-polarization Doppler radar (S-Pol) surface rainfall data for two different periods. Moreover, the performance of this rainfall estimation technique is evaluated against well-known methods, namely, the TRMM-2A12 [ the Goddard profiling algorithm (GPROF)], the Goddard scattering algorithm (GSCAT), and the National Environmental Satellite, Data, and Information Service (NESDIS) algorithms. The proposed algorithm shows a normalized bias of approximately 23% for both PR and S-Pol ground truth datasets and a mean error of 0.244 mm h(-1) ( PR) and -0.157 mm h(-1)(S-Pol). For rain volume estimates using PR as reference, a correlation coefficient of 0.939 and a normalized bias of 0.039 were found. With respect to rainfall distributions and rain area comparisons, the results showed that the formulation proposed is efficient and compatible with the physics and dynamics of the observed systems over the area of interest. The performance of the other algorithms showed that GSCAT presented low normalized bias for rain areas and rain volume [0.346 ( PR) and 0.361 (S-Pol)], and GPROF showed rainfall distribution similar to that of the PR and S-Pol but with a bimodal distribution. Last, the five algorithms were evaluated during the TRMM-Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) 1999 field campaign to verify the precipitation characteristics observed during the easterly and westerly Amazon wind flow regimes. The proposed algorithm presented a cumulative rainfall distribution similar to the observations during the easterly regime, but it underestimated for the westerly period for rainfall rates above 5 mm h(-1). NESDIS(1) overestimated for both wind regimes but presented the best westerly representation. NESDIS(2), GSCAT, and GPROF underestimated in both regimes, but GPROF was closer to the observations during the easterly flow. | |||||
BibTeX:
@article{biscaro_continental_2008, author = {Biscaro, T.S. and Morales, C.A.}, title = {Continental passive microwave-based rainfall estimation algorithm: Application to the Amazon Basin}, journal = {Journal of Applied Meteorology and Climatology}, year = {2008}, volume = {47}, number = {7}, pages = {1962--1981}, url = {://WOS:000257718300007 http://journals.ametsoc.org/doi/pdf/10.1175/2007JAMC1744.1}, doi = {https://doi.org/10.1175/2007jamc1744.1} } |
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Birkett, C.M., Mertes, L.A.K., Dunne, T., Costa, M.H. and Jasinski, M.J. | Surface water dynamics in the Amazon Basin: Application of satellite radar altimetry | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Satellite radar altimetry has the ability to monitor variations in surface water height (stage) for large wetlands, rivers, and associated floodplains. A clear advantage is the provision of data where traditional gauges are absent. As part of an international program, a complete altimetric analysis of the Amazon Basin is being undertaken. Here, an updated and more rigorous evaluation of the TOPEX/POSEIDON (T/P) data set is presented for the first similar to7.5 years of the mission. With an initial study group of 230 targets, height variability at many ungauged locations can be observed for 30-50%, the range reflecting the clarity of the variations in lieu of instrument limitations. An assessment of the instrument performance confirms that the minimum river width attainable is 1 km in the presence of some inundated floodplain. This constraint does allow observation of the main stem (Solimoes/Amazon) and the larger tributaries, but rugged terrain in the vicinity of the target additionally places severe limitations on data retrieval. First-order validation exercises with the deduced 1992-1999 time series of stage fluctuations reveal accuracies ranging from tens of centimeters to several meters (mean similar to1.1 m rms). Altimetric water levels in the Solimoes and Amazon are particularly well defined with amplitudes textless13 m and variations in peak-level timing from May to July. The water-surface gradient of the main stem is found to vary both spatially and temporally, with values ranging from 1.5 cm/km downstream to 4.0 cm/km for more upstream reaches. In agreement with ground-based estimates, the seasonal variability of the gradients reveals that the hysteresis characteristic of the flood wave varies along the main stem and the derived altimetric velocity of this flood wave is estimated to be &SIM;0.35 m/s. Overall, the altimetric results demonstrate that the T/P mission is successfully monitoring the transient flood waves of this continental-scale river basin. | |||||
BibTeX:
@article{birkett_surface_2002, author = {Birkett, C. M. and Mertes, L. A. K. and Dunne, T. and Costa, M. H. and Jasinski, M. J.}, title = {Surface water dynamics in the Amazon Basin: Application of satellite radar altimetry}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200016 http://www.agu.org/journals/jd/jd0217/2001JD000609/2001JD000609.pdf}, doi = {https://doi.org/10.1029/2001jd000609} } |
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Binks, O.J., Meir, P., Rowland, L., Costa, A.C.L.d., Vasconcelos, S.S., Oliveira, A.d., Ferreira, L. and Mencuccini, M. | Limited acclimation in leaf anatomy to experimental drought in tropical rainforest trees [BibTeX] |
2016 | Tree Physiology Vol. 36, pp. 1550-1561 |
article | DOI |
BibTeX:
@article{binks_limited_2016, author = {Binks, O. J. and Meir, P. and Rowland, L. and Costa, A. C. L. da and Vasconcelos, S. S. and Oliveira, A.A.R. de and Ferreira, L. and Mencuccini, M.}, title = {Limited acclimation in leaf anatomy to experimental drought in tropical rainforest trees}, journal = {Tree Physiology}, year = {2016}, volume = {36}, pages = {1550--1561}, doi = {https://doi.org/10.1093/treephys/tpw078} } |
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Binks, O., Mencuccini, M., Rowland, L., Costa, A.C.L., Carvalho, C.J.R., Bittencourt, P., Eller, C., Teodoro, G.S., Carvalho, E.J.M., Soza, A., Ferreira, L., Vasconcelos, S.S., Oliveira, R. and Meir, P. | Foliar water uptake in Amazonian trees: Evidence and consequences [BibTeX] |
2019 | Global Change Biology Vol. 25, pp. 2679-2690 |
article | |
BibTeX:
@article{binks_foliar_2019, author = {Binks, Oliver and Mencuccini, Maurizio and Rowland, Lucy and Costa, Antonio C. L. and Carvalho, Claudio José Reis and Bittencourt, Paulo and Eller, Cleiton and Teodoro, Grazielle Sales and Carvalho, Eduardo Jorge Maklouf and Soza, Azul and Ferreira, Leandro and Vasconcelos, Steel Silva and Oliveira, Rafael and Meir, Patrick}, title = {Foliar water uptake in Amazonian trees: Evidence and consequences}, journal = {Global Change Biology}, year = {2019}, volume = {25}, pages = {2679--2690} } |
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Binks, O., Meir, P., Rowland, L., da Costa, A., Vasconcelos, S., de Oliveira, A., Ferreira, L., Christofferson, B., Nardini, A. and Mencuccini, M. | Plasticity in leaf-level water relations of tropical rainforest trees in response to experimental drought [BibTeX] |
2015 | New Phytologist Vol. 11, pp. 477-488 |
article | |
BibTeX:
@article{binks_plasticity_2015, author = {Binks, O. and Meir, P. and Rowland, L. and da Costa, ACL. and Vasconcelos, SS. and de Oliveira, AAD. and Ferreira, L. and Christofferson, B. and Nardini, A. and Mencuccini, M.}, title = {Plasticity in leaf-level water relations of tropical rainforest trees in response to experimental drought}, journal = {New Phytologist}, year = {2015}, volume = {11}, pages = {477--488} } |
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Binks, O., Finnigan, J., Coughlin, I., Disney, M., Calders, K., Burt, A., Vicari, M.B., da Costa, A.L., Mencuccini, M. and Meir, P. | Canopy wetness in the Eastern Amazon | 2021 | Agricultural and Forest Meteorology Vol. 297, pp. 108250 |
article | DOI URL |
Abstract: Canopy wetness is a common condition that influences photosynthesis, the leaching or uptake of solutes, the water status and energy balance of canopies, and the interpretation of eddy covariance and remote sensing data. While often treated as a binary variable, ‘wet’ or ‘dry’, forest canopies are often partially wet, requiring the use of a continuous description of wetness. Minor precipitation events such as dew, that wet a fraction of the canopy, have been found to contribute to dry season foliar water uptake in the Eastern Amazon, and are fundamentally important to the canopy energy balance. However, few studies have reported the spatial and temporal distribution of canopy wetness, or the relative contribution of dew to leaf wetness, for forest ecosystems. In this study, we use two canopy profiles of leaf wetness sensors, coupled with meteorological data, to address fundamental questions about spatial and temporal variation of leaf wetness in an Eastern Amazonian rainforest. We also investigate how well meteorological tower data can predict canopy wetness using two models, one empirical and one that is physically-based. The results show that the canopy is 100% dry only for 34% of the time, otherwise being between 5% and 100% wet. Dew accounts for 20% or 43% of total annual leaf wetness, and 36% or 50% of canopy wetness in dry season, excluding or including dew events that co-occur with rain, respectively. Wetness duration was higher at the top than bottom of the canopy, mainly because of rain events, whilst dew formation was strongly dependent on the local canopy structure and varied horizontally through the canopy. The best empirical model accounted for 55% of the variance in canopy wetness, while the physical model accounted for 48% of the variance. We discuss future modelling improvements of the physical model to increase its predictive capacity. | |||||
BibTeX:
@article{binks_canopy_2021, author = {Binks, Oliver and Finnigan, John and Coughlin, Ingrid and Disney, Mathias and Calders, Kim and Burt, Andrew and Vicari, Matheus Boni and da Costa, Antonio Lola and Mencuccini, Maurizio and Meir, Patrick}, title = {Canopy wetness in the Eastern Amazon}, journal = {Agricultural and Forest Meteorology}, year = {2021}, volume = {297}, pages = {108250}, url = {https://www.sciencedirect.com/science/article/pii/S016819232030352X}, doi = {https://doi.org/10.1016/j.agrformet.2020.108250} } |
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Bilsborrow, B., Pan, A.F. and R.E., W. | Changes in population and land use over time in the Ecuadorian Amazon [BibTeX] |
2004 | Acta Amazonica Vol. 34(4), pp. 635-647 |
article | |
BibTeX:
@article{bilsborrow_changes_2004, author = {Bilsborrow, Barbieri, A.F., Pan, W., R.E.}, title = {Changes in population and land use over time in the Ecuadorian Amazon}, journal = {Acta Amazonica}, year = {2004}, volume = {34}, number = {4}, pages = {635--647} } |
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Biggs, T., Dunne, T., Roberts, D. and Matricardi, E. | The rate and extent of deforestation in watersheds of the southwestern Amazon Basin | 2008 | Ecological Applications Vol. 18(1), pp. 31-48 |
article | DOI URL |
Abstract: The rate and extent of deforestation determine the timing and magnitude of disturbance to both terrestrial and aquatic ecosystems. Rapid change can lead to transient impacts to hydrology and biogeochemistry, while complete and permanent conversion to other land uses can lead to chronic changes. A large population of watershed boundaries (N=4788) and a time series of Landsat TM imagery (1975-1999) in the southwestern Amazon Basin showed that even small watersheds (2.5-15 km(2)) were deforested relatively slowly over 7-21 years. Less than 1% of all small watersheds were more than 50% cleared in a single year, and clearing rates averaged 5.6%/yr during active clearing. A large proportion (26%) of the small watersheds had a cumulative deforestation extent of more than 75%. The cumulative deforestation extent was highly spatially autocorrelated up to a 100-150 km lag due to the geometry of the agricultural zone and road network, so watersheds as large as similar to 40000 km(2) were more than 50% deforested by 1999. The rate of deforestation had minimal spatial autocorrelation beyond a lag of similar to 30 km, and the mean rate decreased rapidly with increasing area. Approximately 85% of the cleared area remained in pasture, so deforestation in watersheds of Rondonia was a relatively slow, permanent, and complete transition to pasture, rather than a rapid, transient, and partial cutting with regrowth. Given the observed land-cover transitions, the regional stream biogeochemical response is likely to resemble the chronic changes observed in streams draining established pastures, rather than a temporary pulse from slash-and-burn. | |||||
BibTeX:
@article{biggs_rate_2008, author = {Biggs, T.W. and Dunne, T. and Roberts, D.A. and Matricardi, E.}, title = {The rate and extent of deforestation in watersheds of the southwestern Amazon Basin}, journal = {Ecological Applications}, year = {2008}, volume = {18}, number = {1}, pages = {31--48}, note = {Edition: 2008/04/01}, url = {://WOS:000253371800004 http://www.esajournals.org/doi/pdf/10.1890/06-1689.1}, doi = {https://doi.org/10.1890/06-1689.1} } |
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Biggs, T., Dunne, T. and Muraoka, T. | Transport of water, solutes and nutrients from a pasture hillslope, southwestern Brazilian Amazon | 2006 | Hydrological Processes Vol. 20(12), pp. 2527-2547 |
article | DOI URL |
Abstract: A conceptual model of water and solute transport pathways was developed and applied to a pasture hillslope in the southwestern Brazilian Amazon basin using select field measurements. Infiltration-excess or Horton overland flow (HOF), saturation overland flow (SOF), and groundwater in both the near-stream zone and upslope were sampled on a hillslope draining a 3.9 hectare pasture for a total of ten storms during the first half of the rainy season (October-November) in 2002. A Soil Conservation Service SCS curve number model of HOF and an annual water balance of both upslope and near-stream zones were used to calculate the contribution of each flowpath to solute export. HOF occurred in rainstorms greater than 5 mm and accounted for similar to 8% of annual rainfall. Flow generated in the near-stream zone was similar to 8% of annual rainfall. Sub-surface flow from upslope groundwater dominated annual runoff (similar to 19-30% of annual rainfall). Solutes fell into three categories according to flowpath. HOF from upslope positions dominated the export of total phosphor-us (TP) and total dissolved phosphorus (TDP, 51-72% of total annual export). The near-stream zones controlled the export of K (58-65%), total dissolved nitrogen (TDN, 76-80%), and total nitrogen (TN, similar to 75%) owing to relatively high solute concentrations and the large volume of water that flowed through the near-stream zone. Na and Si export was via groundwater from upslope (50-67% of annual export). The flux calculations were based on a small number of storms and are preliminary estimates designed to identify broad patterns in solute export via different hydrologic pathways. Additional processes, especially N removal at the groundwater-stream interface and in the stream channel, may affect actual export rates at the watershed scale. Whereas HOF production is negligible in Amazon forests, it represents a significant pathway for additional loss of elements, especially phosphorus, from mature pasture systems. The evidence presented here shows that biogeochemical perturbations and enhanced solute fluxes continue for decades following deforestation for pasture. Copyright (C) 2006 John Wiley & Sons, Ltd. | |||||
BibTeX:
@article{biggs_transport_2006, author = {Biggs, T.W. and Dunne, T. and Muraoka, T.}, title = {Transport of water, solutes and nutrients from a pasture hillslope, southwestern Brazilian Amazon}, journal = {Hydrological Processes}, year = {2006}, volume = {20}, number = {12}, pages = {2527--2547}, url = {://WOS:000239670800005 http://onlinelibrary.wiley.com/store/10.1002/hyp.6214/asset/6214_ftp.pdf?v=1&t=h6hxqw0a&s=bed3d89bf5446fa71abaac4f39e4f919bb996173}, doi = {https://doi.org/10.1002/hyp.6214} } |
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Biggs, T.W., Dunne, T. and Martinelli, L.A. | Natural controls and human impacts on stream nutrient concentrations in a deforested region of the Brazilian Amazon basin | 2004 | Biogeochemistry Vol. 68(2), pp. 227-257 |
article | DOI URL |
Abstract: This study documents regional patterns in stream nitrogen and phosphorus concentrations in the Brazilian state of Rondonia in the southwestern Amazon basin, and interprets the patterns as functions of watershed soil properties, deforestation extent, and urban population density. The survey includes 77 different locations sampled in the dry and wet seasons, with a watershed size range from 1.8 to 33,000 km(2) over a total area of approximately 140,000 km(2). A sequential regression technique is used to separate the effects of natural watersheds properties and anthropogenic disturbance on nutrients and chloride. Natural variation in soil texture explains most of the variance in stream nitrate concentrations, while deforestation extent and urban population density explain most of the variance in stream chloride (Cl) and total dissolved nitrogen (TDN) concentrations. Stream TDN, total dissolved phosphorus (TDP), particulate phosphorus (PP) and Cl concentrations all increase non-linearly with deforestation extent in the dry season after controlling for natural variability due to soil type. Stream nutrient and Cl disturbances are observed only in watersheds more than 66-75% deforested (watershed area range 2-300 km(2)), suggesting stream nutrient concentrations are resistant to perturbation from vegetation conversion below a 66-75% threshold. In heavily deforested watersheds, stream Cl shows the largest changes in concentration (12 +/- 6 times forested background), followed by TDP (2.3 +/- 1.5), PP (1.9 +/- 0.8) and TDN (1.7 +/- 0.5). Wet season signals in Cl and TDP are diluted relative to the dry season, and no land use signal is observed in wet season TDN, PN, or PP. Stream TDN and TDP concentrations in non-urban watersheds both correlate with stream Cl, suggesting that sources other than vegetation and soil organic matter contribute to enhanced nutrient concentrations. Small, urbanized watersheds (5-20 km(2)) have up to 40 times the chloride and 10 times the TDN concentrations of forested catchments in the dry season. Several large watersheds (similar to1000-3000 km(2)) with urban populations show higher Cl, TDN and TDP levels than any small pasture watershed, suggesting that human impacts on nutrient concentrations in large river systems may be dominated by urban areas. Anthropogenic disturbance of dry-season stream Cl and TDN is detectable in large streams draining deforested and urbanized watersheds up to 33,000 km(2). We conclude that regional deforestation and urbanization result in changes in stream Cl, N and P concentrations at wide range of scales, from small pasture streams to large river systems. | |||||
BibTeX:
@article{biggs_natural_2004, author = {Biggs, T. W. and Dunne, T. and Martinelli, L. A.}, title = {Natural controls and human impacts on stream nutrient concentrations in a deforested region of the Brazilian Amazon basin}, journal = {Biogeochemistry}, year = {2004}, volume = {68}, number = {2}, pages = {227--257}, url = {://WOS:000221102500006 http://www.springerlink.com/content/m77814q88g661g55/fulltext.pdf}, doi = {https://doi.org/10.1023/B:BIOG.0000025744.78309.2e} } |
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Biggs, T.W., Dunne, T., Domingues, T.F. and Martinelli, L.A. | Relative influence of natural watershed properties and human disturbance on stream solute concentrations in the southwestern Brazilian Amazon basin | 2002 | Water Resources Research Vol. 38(8) |
article | DOI URL |
Abstract: [1] We use a synoptic sampling of stream water to quantify the effect of soil type, rock type, deforestation extent determined by Landsat TM imagery, and urban population density on stream solute concentrations for 60 different watersheds in the dry season and 49 in the wet season in the southwestern Brazilian Amazon basin. Catchment areas range between 18 and 12,500 km(2). Soil exchangeable cation content explains most of the variance in stream concentrations of cations, dissolved silicon ( Si), and acid neutralizing capacity (ANC) in both forested and deforested basins based on regression analysis (R-2 range 0.61-0.81), though the mechanism underlying the relationship is unknown. We use the relationship between soil exchangeable cation content and stream solute concentrations in forested catchments to estimate the predisturbance and postdisturbance signal concentrations of stream solutes for deforested watersheds. Signal concentrations of potassium ( K), sodium (Na), and chloride (Cl) increase with deforestation extent for streams on gneiss, granite, and sedimentary rock in both the dry and wet seasons after the effect of soil type has been statistically removed. Sulfate (SO4) signal concentrations increase with deforestation extent in the dry season only. For catchments textgreater 40% deforested but with no urban populations, the ratios of disturbed to predisturbance stream concentrations range from 1.2 to 3.1 (K), 0.8 to 2.2 (Na), 0.7 to 2.7 (SO4), and 2.4 to 14.6 (Cl) in the dry season and 1.2 to 2.2 (K) and 0.6 to 3.4 (Cl) in the wet season. Urban population density strongly affects Cl and SO4 concentrations in both seasons and Na concentrations in the dry season; the urban signal comprises 40-58% of the dry season Cl signal and 83-89% of the wet season Cl signal for watersheds with textgreater 250 persons per km(2). Streams on mica-schist, mafic rock and carbonate shale have higher concentrations of Ca, Mg, Si, andANC than watersheds on gneiss, granite, tertiary sediments or sandstone for a given soil exchangeable cation content in both seasons. Simple mass balance calculations suggest that supplemental cattle salts could comprise a significant fraction of the Na and Cl signals in the wet season but would not significantly impact wet season concentrations of Ca, Mg, or K. | |||||
BibTeX:
@article{biggs_relative_2002, author = {Biggs, T. W. and Dunne, T. and Domingues, T. F. and Martinelli, L. A.}, title = {Relative influence of natural watershed properties and human disturbance on stream solute concentrations in the southwestern Brazilian Amazon basin}, journal = {Water Resources Research}, year = {2002}, volume = {38}, number = {8}, url = {://WOS:000179644000001 http://www.agu.org/pubs/crossref/2002/2001WR000271.shtml}, doi = {https://doi.org/10.1029/2001wr000271} } |
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Biazeto, B. and Silva-Dias, M. | Analysis of the impact of rainfall assimilation during LBA atmospheric mesoscale missions in Southwest Amazon | 2012 | Atmospheric Research Vol. 107, pp. 126- 144 |
article | DOI URL |
Abstract: The assimilation of satellite estimated precipitation data can be used as an efficient tool to improve the analysis of rainfall generated by numerical models of weather forecast. The system of data assimilation used in this study is cumulus parameterization inversion based on the Kuo scheme. Reanalysis were performed using the field experiment data of the LBA Project (WETAMC and DRYtoWET-AMC), where it was possible to verify an improvement in the simulations results, since the data assimilation corrects the position and the intensity of rainfall in the numerical model. (C) 2012 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{biazeto_analysis_2012, author = {Biazeto, B. and Silva-Dias, M.A.F}, title = {Analysis of the impact of rainfall assimilation during LBA atmospheric mesoscale missions in Southwest Amazon}, journal = {Atmospheric Research}, year = {2012}, volume = {107}, pages = {126-- 144}, url = {://000302507500012}, doi = {https://doi.org/10.1016/j.atmosres.2012.01.004} } |
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Bian, L. and Walsh, S.J. | Characterizing and modeling landscape dynamics: An introduction [BibTeX] |
2002 | Photogrammetric Engineering and Remote Sensing Vol. 68(10), pp. 999-1000 |
article | URL |
BibTeX:
@article{bian_characterizing_2002, author = {Bian, L. and Walsh, S. J.}, title = {Characterizing and modeling landscape dynamics: An introduction}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2002}, volume = {68}, number = {10}, pages = {999--1000}, url = {://WOS:000178338800006} } |
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Bezerra, V.L., Dias-Júnior, C.Q., Vale, R.S., Santana, R.A., Botía, S., Manzi, A.O., Cohen, J.C.P., Martins, H.S., Chamecki, M. and Fuentes, J.D. | Near-Surface Atmospheric Turbulence in the Presence of a Squall Line above a Forested and Deforested Region in the Central Amazon [BibTeX] |
2021 | Atmosphere Vol. 12(4), pp. 461 |
article | URL |
BibTeX:
@article{bezerra_near-surface_2021, author = {Bezerra, Valéria L. and Dias-Júnior, Cléo Q. and Vale, Roseilson S. and Santana, Raoni A. and Botía, Santiago and Manzi, Antônio O. and Cohen, Julia C. P. and Martins, Hardiney S. and Chamecki, Marcelo and Fuentes, Jose D.}, title = {Near-Surface Atmospheric Turbulence in the Presence of a Squall Line above a Forested and Deforested Region in the Central Amazon}, journal = {Atmosphere}, year = {2021}, volume = {12}, number = {4}, pages = {461}, url = {https://www.mdpi.com/2073-4433/12/4/461} } |
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Bevis, M., Alsdorf, D., Kendrick, E., Fortes, L.P., Forsberg, B., Smalley, R. and Becker, J. | Seasonal fluctuations in the mass of the Amazon River system and Earth's elastic response | 2005 | Geophysical Research Letters Vol. 32(16) |
article | DOI URL |
Abstract: A GPS station in Manaus, near the center of the Amazon basin, manifests an annual cycle of vertical displacement with a peak-to-peak amplitude of 50 - 75 mm. This is by far the largest crustal oscillation observed to date, and nearly 2 - 3 times larger than the amplitude predicted for this region. Vertical ground displacement is strongly anticorrelated with the local stage height of the Amazon river, with no detectable time lag between the two time series. This suggests that we are observing, for the first time, a purely elastic response to changes in the weight of a flowing river system. We use a simple hydrological model to relate stage height to the regional pattern of flooding, and argue that the elastic oscillations observed in Manaus are dominated by changes in water loading developed within similar to 200 km of the GPS station. | |||||
BibTeX:
@article{bevis_seasonal_2005, author = {Bevis, M. and Alsdorf, D. and Kendrick, E. and Fortes, L. P. and Forsberg, B. and Smalley, R. and Becker, J.}, title = {Seasonal fluctuations in the mass of the Amazon River system and Earth's elastic response}, journal = {Geophysical Research Letters}, year = {2005}, volume = {32}, number = {16}, url = {://WOS:000231568500003 http://www.agu.org/pubs/crossref/2005/2005GL023491.shtml}, doi = {https://doi.org/10.1029/2005gl023491} } |
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Bevan, S.L., North, P.R.J., Grey, W.M.F., Los, S.O. and Plummer, S.E. | Impact of atmospheric aerosol from biomass burning on Amazon dry-season drought | 2009 | Journal of Geophysical Research: Atmospheres Vol. 114(D9) |
article | DOI URL |
Abstract: It is becoming increasingly apparent that the future of the Amazon rainforest is under threat from both climate change and agricultural practices such as deforestation and biomass burning. Atmospheric aerosols are likely to play an important role in the interaction between deforestation, fire and drought, but until now, observations of aerosol optical depth (AOD) in this region have been limited to time series of less than 7 years for satellite retrievals, or to single-site measurements. Here we use a 13-year time series of Along Track Scanning Radiometer derived AOD measurements to examine the role of aerosols in biosphere-climate interactions over the Amazon. The seasonal cycle of AOD shows peaks in March and September. The September peak is caused by local dry-season biomass burning. The March peak has not been identified previously but is coincident with more remote fires located in northern South America. A decreasing trend in dry-season AOD between 1995 and 2000 and a subsequent increase from 2000 to 2004 can be explained by deforestation practices driven by economic forces, whereas even higher AOD levels in 2005 were probably caused more by the exceptional drought of that year. Throughout the time series, dry-season AODs are inversely correlated with dry-season precipitation, suggesting a positive feedback between aerosols and drought that may contribute to enhanced drought under climate change. | |||||
BibTeX:
@article{bevan_impact_2009, author = {Bevan, Suzanne L. and North, Peter R. J. and Grey, William M. F. and Los, Sietse O. and Plummer, Stephen E.}, title = {Impact of atmospheric aerosol from biomass burning on Amazon dry-season drought}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2009}, volume = {114}, number = {D9}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2008JD011112}, doi = {https://doi.org/10.1029/2008JD011112} } |
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Betts, R.A., Malhi, Y. and Roberts, J.T. | The future of the Amazon: new perspectives from climate, ecosystem and social sciences | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1729-1735 |
article | DOI URL |
Abstract: The potential loss or large-scale degradation of the tropical rainforests has become one of the iconic images of the impacts of twenty-first century environmental change and may be one of our century's most profound legacies. In the Amazon region, the direct threat of deforestation and degradation is now strongly intertwined with an indirect challenge we are just beginning to understand: the possibility of substantial regional drought driven by global climate change. The Amazon region hosts more than half of the world's remaining tropical forests, and some parts have among the greatest concentrations of biodiversity found anywhere on Earth. Overall, the region is estimated to host about a quarter of all global biodiversity. It acts as one of the major 'flywheels' of global climate, transpiring water and generating clouds, affecting atmospheric circulation across continents and hemispheres, and storing substantial reserves of biomass and soil carbon. Hence, the ongoing degradation of Amazonia is a threat to local climate stability and a contributor to the global atmospheric climate change crisis. Conversely, the stabilization of Amazonian deforestation and degradation would be an opportunity for local adaptation to climate change, as well as a potential global contributor towards mitigation of climate change. However, addressing deforestation in the Amazon raises substantial challenges in policy, governance, sustainability and economic science. This paper introduces a theme issue dedicated to a multidisciplinary analysis of these challenges. | |||||
BibTeX:
@article{betts_future_2008, author = {Betts, Richard A. and Malhi, Yadvinder and Roberts, J. Timmons}, title = {The future of the Amazon: new perspectives from climate, ecosystem and social sciences}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1729--1735}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500002 http://rstb.royalsocietypublishing.org/content/363/1498/1729.full.pdf}, doi = {https://doi.org/10.1098/rstb.2008.0011} } |
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Betts, R.A., Cox, P.M., Collins, M., Harris, P.P., Huntingford, C. and Jones, C.D. | The role of ecosystem-atmosphere interactions in simulated Amazonian precipitation decrease and forest dieback under global climate warming | 2004 | Theoretical and Applied Climatology Vol. 78(1-3), pp. 157-175 |
article | DOI URL |
Abstract: A suite of simulations with the HadCM3LC coupled climate-carbon cycle model is used to examine the various forcings and feedbacks involved in the simulated precipitation decrease and forest dieback. Rising atmospheric CO2 is found to contribute 20% to the precipitation reduction through the physiological forcing of stomatal closure, with 80% of the reduction being seen when stomatal closure was excluded and only radiative forcing by CO2 was included. The forest dieback exerts two positive feedbacks on the precipitation reduction; a biogeophysical feedback through reduced forest cover suppressing local evaporative water recycling, and a biogeochemical feedback through the release of CO2 contributing to an accelerated global warming. The precipitation reduction is enhanced by 20% by the biogeophysical feedback, and 5% by the carbon cycle feedback from the forest dieback. This analysis helps to explain why the Amazonian precipitation reduction simulated by HadCM3LC is more extreme than that simulated in other GCMs; in the fully-coupled, climate-carbon cycle simulation, approximately half of the precipitation reduction in Amazonia is attributable to a combination of physiological forcing and biogeophysical and global carbon cycle feedbacks, which are generally not included in other GCM simulations of future climate change. The analysis also demonstrates the potential contribution of regional-scale climate and ecosystem change to uncertainties in global CO2 and climate change projections. Moreover, the importance of feedbacks suggests that a human-induced increase in forest vulnerability to climate change may have implications for regional and global scale climate sensitivity. | |||||
BibTeX:
@article{betts_role_2004, author = {Betts, R. A. and Cox, P. M. and Collins, M. and Harris, P. P. and Huntingford, C. and Jones, C. D.}, title = {The role of ecosystem-atmosphere interactions in simulated Amazonian precipitation decrease and forest dieback under global climate warming}, journal = {Theoretical and Applied Climatology}, year = {2004}, volume = {78}, number = {1-3}, pages = {157--175}, url = {://WOS:000222024700012 http://www.springerlink.com/content/bkapqlxkdgc08c5r/fulltext.pdf}, doi = {https://doi.org/10.1007/s00704-004-0050-y} } |
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Betts, A.K. and Viterbo, P. | Land-surface, boundary layer, and cloud-field coupling over the southwestern Amazon in ERA-40 | 2005 | Journal of Geophysical Research-Atmospheres Vol. 110(D14) |
article | DOI URL |
Abstract: Models are powerful tools for understanding the coupling of physical processes. We illustrate this using averages from ERA-40 for the Madeira River, a southwestern basin of the Amazon, which has a large seasonal cycle with a dry season in the austral winter. Daily-mean land-surface fluxes and state variables can be used to map the transitions of the surface "climate'' of a model and to quantify the links between the soil moisture, the mean cloud-base and cloud field, the shortwave and longwave radiation fields at the surface, the vertical motion field, the atmospheric precipitable water, and the surface precipitation. The links that are visible on a daily timescale can also be seen on the seasonal timescale. Several important surface processes are strongly influenced by soil moisture: relative humidity, which gives the mixed subcloud layer depth, low cloud cover, and the surface net long-wave flux. The link between soil moisture and equivalent potential temperature can therefore be clearly seen once the temperature dependence is filtered. Surface evaporation is controlled as much by the feedback of the cloud field on the surface radiation budget as by soil moisture. Above the surface the cloud field and precipitation are coupled to the large-scale dynamics, specifically the midtropospheric omega field. The shortwave cloud forcing of the atmosphere and the surface is given by the cloud field albedo at the top of the atmosphere to better than 1%. We have developed a new methodology for understanding the coupling and feedbacks between physical processes in models, so that different models can be compared with each other and with data. | |||||
BibTeX:
@article{betts_land-surface_2005, author = {Betts, A. K. and Viterbo, P.}, title = {Land-surface, boundary layer, and cloud-field coupling over the southwestern Amazon in ERA-40}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2005}, volume = {110}, number = {D14}, url = {://WOS:000230941500003 http://www.agu.org/journals/jd/jd0514/2004JD005702/2004JD005702.pdf}, doi = {https://doi.org/10.1029/2004jd005702} } |
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Betts, A.K. and Jakob, C. | Evaluation of the diurnal cycle of precipitation, surface thermodynamics, and surface fluxes in the ECMWF model using LBA data | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] The mean diurnal cycle of precipitation, near-surface thermodynamics and surface fluxes from short-term forecasts of the ECMWF model are compared with corresponding observations from the Large-Scale Biosphere-Atmosphere Experiment in the Amazonia wet season campaign in 1999 in Rondonia. Precipitation starts about 2 hours after sunrise in the model, several hours earlier than observed, because the model does not simulate well the morning growth of the nonprecipitating convective boundary layer. However, the mean daily precipitation during the wet season compares well with observed rainfall. On most days, maximum early afternoon temperature and cloud base height are lower in the model than observed. Maximum equivalent potential temperature is close to that observed. The model surface evaporative fraction is higher than observed and rises to near unity in the late afternoon. Work is in progress to evaluate and integrate the parameterizations for shallow and deep convection. | |||||
BibTeX:
@article{betts_evaluation_2002, author = {Betts, A. K. and Jakob, C.}, title = {Evaluation of the diurnal cycle of precipitation, surface thermodynamics, and surface fluxes in the ECMWF model using LBA data}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200002 http://www.agu.org/journals/jd/jd0217/2001JD000427/2001JD000427.pdf}, doi = {https://doi.org/10.1029/2001jd000427} } |
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Betts, A.K. and Jakob, C. | Study of diurnal cycle of convective precipitation over Amazonia using a single column model | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D23) |
article | DOI URL |
Abstract: [1] The error in the diurnal cycle of precipitation over land in the tropics in the European Centre for Medium-Range Weather Forecasts forecast model is investigated using a single column model with idealized forcing of the omega field, as well as short-term and long runs of the full three-dimensional model. The model precipitates a few hours after sunrise, as it does not represent correctly the morning development of a growing cumulus boundary layer. In the single column model, precipitation is closely linked to the mean forcing and surface evaporation, but the phase of diurnal varying omega forcing in relation to the diurnal solar cycle determines the relation of convective to large-scale precipitation in the control model, as well as cloudiness and the net radiation balance. With diurnal subsidence peaking at midnight, but no mean ascent, the model shows a quasi 2-day precipitation mode. With both strong mean ascent and diurnal forcing, ascent peaking in the daytime gave stratiform rain with large cloud cover and very low surface net radiation, while daytime subsidence and ascent at night gave strong daytime convective precipitation and high net radiation. | |||||
BibTeX:
@article{betts_study_2002, author = {Betts, A. K. and Jakob, C.}, title = {Study of diurnal cycle of convective precipitation over Amazonia using a single column model}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D23}, url = {://WOS:000181169100010 http://www.agu.org/journals/jd/jd0223/2002JD002264/2002JD002264.pdf}, doi = {https://doi.org/10.1029/2002jd002264} } |
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Betts, A.K., Gatti, L.V., Cordova, A.M., Dias, M. and Fuentes, J.D. | Transport of ozone to the surface by convective downdrafts at night | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: [1] During the Large-Scale Biosphere-Atmosphere Experiment in Amazonia wet season experiment, the near-surface measurements of equivalent potential temperature and ozone at night, when background levels of ozone are low, clearly show that convective downdrafts rapidly transport air with higher ozone and lower equivalent potential temperature down to the surface from around 800 hPa. This largely unreported downward transport of ozone may play a significant role in the photochemistry of the atmosphere boundary layer and increase the surface deposition of ozone. | |||||
BibTeX:
@article{betts_transport_2002, author = {Betts, A. K. and Gatti, L. V. and Cordova, A. M. and Dias, Mafs and Fuentes, J. D.}, title = {Transport of ozone to the surface by convective downdrafts at night}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200003 http://www.agu.org/journals/jd/jd0217/2000JD000158/2000JD000158.pdf}, doi = {https://doi.org/10.1029/2000jd000158} } |
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Betts, A.K., Fuentes, J.D., Garstang, M. and Ball, J.H. | Surface diurnal cycle and boundary layer structure over Rondonia during the rainy season | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: An integrated data set with simultaneous observations at the surface, from tethered balloons within the boundary layer and from rawinsonde ascents, was collected during the wet season experiment of the Large-Scale Biosphere-Atmosphere (LBA) Experiment in Amazonia during January and February of 1999 in support of the ground validation for the Tropical Rainfall Measuring Mission (TRMM). We analyze the surface diurnal cycles of temperature, humidity, lifting condensation level, equivalent potential temperature, and bx64 the surface fluxes of sensible and latent heat, ground heat flux and net radiation, for easterly and westerly wind regimes in the lower troposphere. During the easterly wind regimes, the diurnal evolution of mixing ratio shows that the flux of water vapor through cloud base exceeds the large surface evaporation. There is a trend toward a wetter and cooler subcloud layer as the rainy season progresses. Daytime surface Bowen ratio for this pasture site is about 0.4, and falls slightly as the rainy season progresses. Typically in the afternoon, evaporatively driven downdrafts from convective rainbands transform the boundary layer. The fall of equivalent potential temperature in the boundary layer is similar for both regimes, but the boundary layer cooling by convective events during the westerly regimes is reduced, because the subcloud layer is shallower on average. Tethersonde ascents through the edges of gust fronts show that subcloud air is first cooled and moistened by rainfall evaporation before the arrival of downdraft air at the surface. These measurements provide a detailed observational basis for the validation and improvement of parameterizations for shallow and deep convection in numerical forecast models. | |||||
BibTeX:
@article{betts_surface_2002, author = {Betts, A. K. and Fuentes, J. D. and Garstang, M. and Ball, J. H.}, title = {Surface diurnal cycle and boundary layer structure over Rondonia during the rainy season}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200021 http://www.agu.org/journals/jd/jd0217/2001JD000356/2001JD000356.pdf}, doi = {https://doi.org/10.1029/2001jd000356} } |
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Betts, A.K., Fisch, G., von Randow, C., Silva Dias, M.A.F., Cohen, J.C.P., da Silva, R. and Fitzjarrald, D.R. | The Amazonian Boundary Layer and Mesoscale Circulations | 2009 | Vol. 186Amazonia and Global Change, pp. 163-182 |
incollection | DOI URL |
Abstract: The interactions between the Amazonian boundary layer, the surface, atmospheric convection, aerosols, and larger-scale circulations are complex. The field experiments in Amazonia have provided rich insights into the daytime and nighttime boundary layer in different regions and seasons over both forest and pasture and into the coupling between the surface fluxes, the boundary layer, precipitation, and cloud radiative forcing. We discuss the typical diurnal cycle of Amazonian convection, the self-organization into mesoscale systems in different synoptic regimes, and the role of forest and river breeze circulations. We review the coupling between aerosols, smoke, and convection in the dry season; ozone transports by deep convection; and microphysical and electrical impacts on convection. | |||||
BibTeX:
@incollection{keller_amazonian_2009, author = {Betts, A. K. and Fisch, G. and von Randow, C. and Silva Dias, M. A. F. and Cohen, J. C. P. and da Silva, R. and Fitzjarrald, D. R.}, title = {The Amazonian Boundary Layer and Mesoscale Circulations}, booktitle = {Amazonia and Global Change}, year = {2009}, volume = {186}, pages = {163--182}, url = {://WOS:000289443400011 http://www.agu.org/books/gm/v186/2008GM000725/2008GM000725.shtml}, doi = {https://doi.org/10.1029/2008gm000725} } |
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Betts, A.K., Ball, J.H., Viterbo, P., Dai, A. and Marengo, J. | Hydrometeorology of the Amazon in ERA-40 | 2005 | Journal of Hydrometeorology Vol. 6(5), pp. 764-774 |
article | DOI URL |
Abstract: The hydrometeorology of the Amazon basin in the ERA-40 reanalysis for 1958-2001 is compared with observations of precipitation, temperature, and streamflow. After 1979, the reanalysis over the Amazon has a small cool bias of the order of -0.35 K, and a small low bias of precipitation of the order of -0.3 mm day(-1). In the early years (1958-72), there is a large upward drift in reanalysis precipitation and runoff associated with an upward drift in the atmospheric water vapor in the analysis, and a somewhat smaller downward drift of temperature as precipitation increases. In the presatellite data, there are inhomogeneities in the radiosonde and surface synoptic data, and there were problems with the variational analysis of humidity once satellite radiances were introduced. Approximate bias corrections can be made for precipitation and runoff on an annual basis, but this also removes some of the interannual variability. The reanalysis runoff-precipitation relationship is similar to the observed streamflow-precipitation relation, on an annual water-year basis. Compared to observations, ERA-40 precipitation for the Amazon is low by about 1.3 mm day(-1) in the rainy season, and high by a smaller amount in the dry season. The precipitation bias produces a temperature bias in ERA-40 of the opposite sign on the annual time scale. The reanalysis has a small cold temperature bias after 1967, but on an annual time scale it reproduces the interannual variability of the observations. Although the biases in temperature and precipitation in recent decades are small, the difficulties with the analysis of atmospheric water vapor lead to large uncertainty in long-term trends of the water cycle. | |||||
BibTeX:
@article{betts_hydrometeorology_2005, author = {Betts, A. K. and Ball, J. H. and Viterbo, P. and Dai, A. and Marengo, J.}, title = {Hydrometeorology of the Amazon in ERA-40}, journal = {Journal of Hydrometeorology}, year = {2005}, volume = {6}, number = {5}, pages = {764--774}, url = {://WOS:000233288800012 http://journals.ametsoc.org/doi/pdf/10.1175/JHM441.1}, doi = {https://doi.org/10.1175/jhm441.1} } |
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Betts, A.K. | Understanding hydrometeorology using global models | 2004 | Bulletin of the American Meteorological Society Vol. 85(11), pp. 1673-+ |
article | DOI URL |
Abstract: The land surface coupling, a crucial element of the climate system, is explored in the recent 40-yr European Centre for Medium-Range Forecasts (ECMWF) reanalysis (ERA-40) model. In seasonal forecasts for the Northern Hemisphere summer, initialized with idealized soil moisture fields, the ERA-40 model has a large evaporation-precipitation feedback over the continents, and the memory of initial soil moisture is longest at high northern latitudes. Thirty years of hourly data from the ERA-40 reanalysis are averaged over the Madeira, Red-Arkansas, and Athabasca River basins. Although the model fully resolves the diurnal cycle and has an interactive prognostic cloud field, the transitions in the boundary layer climate over land can be mapped with remarkable precision by the daily mean state and daily flux averages. The coupling to cloud processes plays an essential role in the surface and boundary layer equilibrium. Soil moisture, cloud base, cloud cover, radiation fields, and evaporative fraction are coupled quite tightly on daily time scales. The long wave flux control by cloud-base height and cloud cover is particularly strong across all basins. Evaporation can be regarded as being determined somewhat indirectly by the dependence of net radiation on cloud cover and cloud base, and sensible heat flux on subcloud-layer processes. Cloud and boundary layer processes and the land surface components of a model must be evaluated as a tightly coupled system, not as independent components. This analysis provides a new frame-work for comparing global models with each other, and for evaluating them against observations. | |||||
BibTeX:
@article{betts_understanding_2004, author = {Betts, A. K.}, title = {Understanding hydrometeorology using global models}, journal = {Bulletin of the American Meteorological Society}, year = {2004}, volume = {85}, number = {11}, pages = {1673--+}, url = {://WOS:000225557200009 http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-85-11-1673}, doi = {https://doi.org/10.1175/bams-85-11-1673} } |
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Betts, A.K. | Idealized model for equilibrium boundary layer over land | 2000 | Journal of Hydrometeorology Vol. 1(6), pp. 507-523 |
article | DOI URL |
Abstract: An idealized equilibrium mixed layer (ML) model is used to explore the coupling between the surface, the ML. and the atmosphere above. It shows that ML depth increases as vegetative resistance to evaporation increases. The surface radiative forcing also increases ML depth: the ML radiative and evaporative cooling processes reduce ML depth. The model largely uncouples mean ML structure from the mean ML fluxes. The upper boundary condition controls ML potential temperature and mixing ratio but does not affect the fluxes; it is the surface radiative forcing and the radiative and evaporative cooling terms within the ML (together with the vegetative resistance R-v) that control the surface fluxes and evaporative fraction. Furthermore, for a given R-v, the radiative and evaporative cooling terms in the ML control the surface sensible heat flux. and the surface radiative forcing then controls the surface latent heat flux. The solutions show that, except for extreme high values of vegetative resistance and very dry air above the ML. this idealized equilibrium ML is capped by shallow cumulus clouds. as over the ocean. At the same time as R-v increases, the ML structure and depth shift from the oceanic limit toward a warmer, drier boundary layer. It is shown that surface evaporation controls equilibrium near-surface relative humidity and not vice versa. The equilibrium solutions also give insight into how the gradient of mean mixing ratio across, the Mississippi River basin is linked to changes in surface pressure as well as vegetative resistance to evaporation. The equilibrium model is oversimplified. and the nonlinearities introduced by the diurnal cycle have nor been addressed, but nonetheless the solutions are a plausible zero-order fit to daily mean model data for the Missouri and Arkansas-Red River basins and to summer composites from the First International Land-Surface Climatology Project Field Experiment. | |||||
BibTeX:
@article{betts_idealized_2000, author = {Betts, A. K.}, title = {Idealized model for equilibrium boundary layer over land}, journal = {Journal of Hydrometeorology}, year = {2000}, volume = {1}, number = {6}, pages = {507--523}, url = {://WOS:000166701200003 http://journals.ametsoc.org/doi/pdf/10.1175/1525-7541%282000%29001%3C0507%3AIMFEBL%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1525-7541(2000)001%3C0507:imfebl%3E2.0.co;2} } |
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Berrêdo, C., M.L.da, V., M.S.P., M. and C.R.L., J. | Modificações nas propriedades físico-químicas de sedimentos de manguezais submetidos ao clima amazônico [BibTeX] |
2017 | Boletim Museu Paraense Emílio Goeldi Ciencias Naturais Vol. 11(3), pp. 313-328 |
article | |
BibTeX:
@article{berredo_modificacoes_2017, author = {Berrêdo, Costa, M.L.da, Vilhena, M.S.P., Matos, C.R.L., J.F.}, title = {Modificações nas propriedades físico-químicas de sedimentos de manguezais submetidos ao clima amazônico}, journal = {Boletim Museu Paraense Emílio Goeldi Ciencias Naturais}, year = {2017}, volume = {11}, number = {3}, pages = {313--328} } |
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Bernoux, M., Feller, C., Cerri, C.C., Eschenbrenner, V. and Cerri, C.E.P. | Soil carbon sequestration [BibTeX] |
2006 | Soil Erosion and Carbon Dynamics, pp. 13-22 | incollection | URL |
BibTeX:
@incollection{roose_soil_2006, author = {Bernoux, M. and Feller, C. and Cerri, C. C. and Eschenbrenner, V. and Cerri, C. E. P.}, title = {Soil carbon sequestration}, booktitle = {Soil Erosion and Carbon Dynamics}, year = {2006}, pages = {13--22}, url = {://WOS:000236318600002} } |
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Bernoux, M., Cerri, C.C., Cerri, C.E.P., Neto, M.S., Metay, A., Perrin, A.S., Scopel, E., Razafimbelo, T., Blavet, D., Piccolo, M.D., Pavei, M. and Milne, E. | Cropping systems, carbon sequestration and erosion in Brazil, a review | 2006 | Agronomy for Sustainable Development Vol. 26(1), pp. 1-8 |
article | DOI URL |
Abstract: Soils represent a large carbon pool, approximately 1500 Gt, which is equivalent to almost three times the quantity stored in terrestrial biomass and twice the amount stored in the atmosphere. Any modification of land use or land management can induce variations in soil carbon stocks, even in agricultural systems that are perceived to be in a steady state. Tillage practices often induce soil aerobic conditions that are favourable to microbial activity and may lead to a degradation of soil structure. As a result, mineralisation of soil organic matter increases in the long term. The adoption of no-tillage systems and the maintenance of a permanent vegetation cover using Direct seeding Mulch-based Cropping system or DMC, may increase carbon levels in the topsoil. In Brazil, no-tillage practices (mainly DMC), were introduced approximately 30 years ago in the south in the Parana state, primarily as a means of reducing erosion. Subsequently, research has begun to study the management of the crop waste products and their effects on soil fertility, either in terms of phosphorus management, as a means of controlling soil acidity, or determining how manures can be applied in a more localised manner. The spread of no-till in Brazil has involved a large amount of extension work. The area under no-tillage is still increasing in the centre and north of the country and currently occupies ca. 20 million hectares, covering a diversity of environmental conditions, cropping systems and management practices. Most studies of Brazilian soils give rates of carbon storage in the top 40 cm of the soil of 0.4 to 1.7 t C ha(-1) per year, with the highest rates in the Cerrado region. However, caution must be taken when analysing DMC systems in terms of carbon sequestration. Comparisons should include changes in trace gas fluxes and should not be limited to a consideration of carbon storage in the soil alone if the full implications for global warming are to be assessed. | |||||
BibTeX:
@article{bernoux_cropping_2006, author = {Bernoux, M. and Cerri, C. C. and Cerri, C. E. P. and Neto, M. S. and Metay, A. and Perrin, A. S. and Scopel, E. and Razafimbelo, T. and Blavet, D. and Piccolo, M. D. and Pavei, M. and Milne, E.}, title = {Cropping systems, carbon sequestration and erosion in Brazil, a review}, journal = {Agronomy for Sustainable Development}, year = {2006}, volume = {26}, number = {1}, pages = {1--8}, url = {://WOS:000236003300001 http://www.agronomy-journal.org/index.php?option=com_article&access=doi&doi=10.1051/agro:2005055&Itemid=129}, doi = {https://doi.org/10.1051/agro:2005055} } |
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Bernoux, M., Carvalho, M.D.S., Volkoff, B. and Cerri, C.C. | Brazil's soil carbon stocks | 2002 | Soil Science Society of America Journal Vol. 66(3), pp. 888-896 |
article | URL |
Abstract: Soil organic carbon (C) stocks to a depth of 30 cm were estimated for Brazil on the basis of a map of different soil-vegetation associations (SVA) combined with results from a soil database. The SVA map was derived by intersection of soil and vegetation maps. The original soil and vegetation classification were simplified to six soil and 15 vegetation categories. The SVA map comprised 21 111 map units (MU) that were spread into 75 different SVA categories. Mean representative C stocks (RCS) of the SVA categories ranged from 1.51 to 41.78 kg cm(-2). More than three fourth of all SVA areas had an associated RCS varying between 3 and 6 kg C m(-2). Because these data represent sites with native vegetation in the absence of significant disturbances, they represent a valuable baseline for evaluating the effect of land-use change on soil C stocks for Brazil. In total, about 36.4 +/- 3.4 Pg C was stored in the 0- to 30-cm soil layer. | |||||
BibTeX:
@article{bernoux_brazils_2002, author = {Bernoux, M. and Carvalho, M. D. S. and Volkoff, B. and Cerri, C. C.}, title = {Brazil's soil carbon stocks}, journal = {Soil Science Society of America Journal}, year = {2002}, volume = {66}, number = {3}, pages = {888--896}, url = {://WOS:000175288300024} } |
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Bernardes, M.C., Martinelli, L.A., Krusche, A.V., Gudeman, J., Moreira, M., Victoria, R.L., Ometto, J., Ballester, M.V.R., Aufdenkampe, A.K., Richey, J.E. and Hedges, J.I. | Riverine organic matter composition as a function of land use changes, Southwest Amazon | 2004 | Ecological Applications Vol. 14(4), pp. S263-S279 |
article | URL |
Abstract: We investigated the forms and composition of dissolved and particulate organic matter in rivers of the Ji-Parana Basin, which is situated at the southern limit of the Amazon lowlands and has experienced extensive deforestation in the last three decades (similar to35 000 km(2)). Our objective was to investigate how extensive land-use changes, from forest to cattle pasture, have affected river biogeochemistry. We measured a series of chemical, biochemical, and isotopic tracers in three size classes of organic matter within five sites along Ji-Parana River and eight more sites in six tributaries. The results were compared with C-4 leaf and pasture soils end members in order to test for a pasture-derived signal in the riverine organic matter. The coarse size fraction was least degraded and derived primarily from fresh leaves in lowland forests. The fine fraction was mostly associated with a mineral soil phase but its ultimate source appeared to be leaves from forests; this fraction was the most enriched in nitrogen. The ultrafiltered dissolved organic matter (UDOM) appeared to have the same source as the coarse fraction, but it was the most extensively degraded of the three fractions. In contrast to Amazon white-water rivers, rivers of the Ji-Parana Basin had lower concentrations of suspended solids with a higher carbon and nitrogen content in the three size. fractions. However, principal component analyses showed a correlation between areas covered with pasture and the delta(13)C values of the three size fractions. The highest a delta(13)C values were observed in the ultrafiltered dissolved organic matter of the Rolim-de-Moura and Jaru rivers, which have the highest areas covered with pasture. The lower the order of the streams and the higher the pasture area, the greater is the possibility that the C-4-derived organic matter signal will be detected first in the faster-cycling fraction (UDOM). The large change in land use in the Ji-Parana Basin, replacement of primary forests by C-4 pastures for cattle feeding, that has taken place in the last 30-40 yr, has already changed the characteristics of the composition of the riverine organic matter. | |||||
BibTeX:
@article{bernardes_riverine_2004, author = {Bernardes, M. C. and Martinelli, L. A. and Krusche, A. V. and Gudeman, J. and Moreira, M. and Victoria, R. L. and Ometto, Jphb and Ballester, M. V. R. and Aufdenkampe, A. K. and Richey, J. E. and Hedges, J. I.}, title = {Riverine organic matter composition as a function of land use changes, Southwest Amazon}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S263--S279}, url = {://WOS:000223269000022} } |
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Bern, C.R., Townsend, A.R. and Farmer, G.L. | Unexpected dominance of parent-material strontium in a tropical forest on highly weathered soils | 2005 | Ecology Vol. 86(3), pp. 626-632 |
article | DOI URL |
Abstract: Controls over nutrient supply are key to understanding the structure and functioning of terrestrial ecosystems. Conceptual models once held that in situ mineral weathering was the primary long-term control over the availability of many plant nutrients, including the base cations calcium (Ca), magnesium (Mg), and potassium (K). Recent evidence has shown that atmospheric sources of these "rock-derived" nutrients can dominate actively cycling ecosystem pools, especially in systems on highly weathered soils. Such studies have relied heavily on the use of strontium isotopes as a proxy for base-cation cycling. Here we show that vegetation and soil-exchangeable pools of strontium in a tropical rainforest on highly weathered soils are still dominated by local rock sources. This pattern exists despite substantial atmospheric inputs of Sr, Ca. K, and M.g, and despite nearly 100% depletion of these elements from the top 1 m of soil. We present a model demonstrating that modest weathering inputs, resulting from tectonically driven erosion, could maintain parent-material dominance of actively cycling Sr. The majority of tropical forests are oil highly weathered soils but our results suggest that these forests may still show considerable variation in their primary sources of essential nutrients. | |||||
BibTeX:
@article{bern_unexpected_2005, author = {Bern, C. R. and Townsend, A. R. and Farmer, G. L.}, title = {Unexpected dominance of parent-material strontium in a tropical forest on highly weathered soils}, journal = {Ecology}, year = {2005}, volume = {86}, number = {3}, pages = {626--632}, url = {://WOS:000227659700012 http://www.esajournals.org/doi/pdf/10.1890/03-0766}, doi = {https://doi.org/10.1890/03-0766} } |
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Bergamaschi, P., Frankenberg, C., Meirink, J., Krol, M.C., Villani, M., Houweling, S., Dentener, F., Dlugokencky, E., Miller, J., Gatti, L., Engel, A. and Levin, I. | Inverse modeling of global and regional CH4 emissions using SCIAMACHY satellite retrievals | 2009 | Journal of Geophysical Research Vol. 114(D22301), pp. doi:10.1029/2009JD012287 |
article | DOI URL |
Abstract: Methane retrievals from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) instrument onboard ENVISAT provide important information on atmospheric CH4 sources, particularly in tropical regions which are poorly monitored by in situ surface observations. Recently, Frankenberg et al. (2008a, 2008b) reported a major revision of SCIAMACHY retrievals due to an update of spectroscopic parameters of water vapor and CH4. Here, we analyze the impact of this revision on global and regional CH4 emissions estimates in 2004, using the TM5-4DVAR inverse modeling system. Inversions based on the revised SCIAMACHY retrievals yield similar to 20% lower tropical emissions compared to the previous retrievals. The new retrievals improve significantly the consistency between observed and assimilated column average mixing ratios and the agreement with independent validation data. Furthermore, the considerable latitudinal and seasonal bias correction of the previous SCIAMACHY retrievals, derived in the TM5-4DVAR system by simultaneously assimilating high-accuracy surface measurements, is reduced by a factor of similar to 3. The inversions result in significant changes in the spatial patterns of emissions and their seasonality compared to the bottom-up inventories. Sensitivity tests were done to analyze the robustness of retrieved emissions, revealing some dependence on the applied a priori emission inventories and OH fields. Furthermore, we performed a detailed validation of simulated CH4 mixing ratios using NOAA ship and aircraft profile samples, as well as stratospheric balloon samples, showing overall good agreement. We use the new SCIAMACHY retrievals for a regional analysis of CH4 emissions from South America, Africa, and Asia, exploiting the zooming capability of the TM5 model. This allows a more detailed analysis of spatial emission patterns and better comparison with aircraft profiles and independent regional emission estimates available for South America. Large CH4 emissions are attributed to various wetland regions in tropical South America and Africa, seasonally varying and opposite in phase with CH4 emissions from biomass burning. India, China and South East Asia are characterized by pronounced emissions from rice paddies peaking in the third quarter of the year, in addition to further anthropogenic emissions throughout the year. | |||||
BibTeX:
@article{bergamaschi_inverse_2009, author = {Bergamaschi, P. and Frankenberg, C. and Meirink, J.F. and Krol, M. C. and Villani, M.G. and Houweling, S. and Dentener, F. and Dlugokencky, E.J. and Miller, J.B. and Gatti, L.V. and Engel, A. and Levin, I.}, title = {Inverse modeling of global and regional CH4 emissions using SCIAMACHY satellite retrievals}, journal = {Journal of Geophysical Research}, year = {2009}, volume = {114}, number = {D22301}, pages = {doi:10.1029/2009JD012287}, url = {://000271995800001 http://www.agu.org/journals/jd/jd0922/2009JD012287/2009JD012287.pdf}, doi = {https://doi.org/10.1029/2009jd012287} } |
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Berenguer, E., Malhi, Y., Brando, P., Cordeiro, A.N., Ferreira, J., Franc¸a, F., Rossi, L.C., Seixas, M.M. and Barlow, J. | Tree growth and stem carbon accumulation in human-modified Amazonian forests following drought and fire [BibTeX] |
2018 | Phil. Trans. R. Soc. B Vol. 373, pp. 20170308 |
article | DOI |
BibTeX:
@article{berenguer_tree_2018, author = {Berenguer, E. and Malhi, Y. and Brando, P. and Cordeiro, A.C. N. and Ferreira, J. and Franc¸a, F. and L.C., Rossi and Seixas, M. M.M. and Barlow, J.}, title = {Tree growth and stem carbon accumulation in human-modified Amazonian forests following drought and fire}, journal = {Phil. Trans. R. Soc. B}, year = {2018}, volume = {373}, pages = {20170308}, doi = {https://doi.org/10.1098/rstb.2017.0308} } |
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Berenguer, E., Ferreira, J., Gardner, T., Aragão, L., de Camargo, P., Cerri, C., Durigan, M., Oliveira, R.d., Vieira, I. and Barlow, J. | A large-scale field assessment of carbon stocks in human-modified tropical forests [BibTeX] |
2014 | Global Change Biology Vol. 20(12), pp. 3713-3726 |
article | |
BibTeX:
@article{berenguer_large-scale_2014, author = {Berenguer, E. and Ferreira, J. and Gardner, T.A. and Aragão, L.E.O.C. and de Camargo, P.B. and Cerri, C.E.D. and Durigan, M. and Oliveira, R.C. de and Vieira, I.C.G. and Barlow, J.}, title = {A large-scale field assessment of carbon stocks in human-modified tropical forests}, journal = {Global Change Biology}, year = {2014}, volume = {20}, number = {12}, pages = {3713--3726} } |
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Berbert, M.L.C. and Costa, M.H. | Climate change after tropical deforestation: Seasonal variability of surface albedo and its effects on precipitation change | 2003 | Journal of Climate Vol. 16(12), pp. 2099-2104 |
article | DOI URL |
Abstract: This work studies the seasonal effects of the surface albedo change after a tropical deforestation and its influence on the seasonal pattern of precipitation in Amazonia. Results of the climate simulation study of Costa and Foley are used to represent the precipitation changes in a scenario where all tropical forest was replaced by pasture. The simulated forest and pasture albedo are compared to both the forest and pasture albedos observed during the Anglo-Brazilian Amazonian Climate Observation Study (ABRACOS) project. The surface albedo measurements provided verification that both forest and pasture albedo show seasonal variability, with the forest albedos higher in the dry period ( June - November) and lower values in the rainy period ( December - May), while the pasture albedo decreases in the dry season. Most of the characteristics of the observed differences in albedo are present in the simulated albedo too, which is in part due to the ability of the land surface parameterization to represent vegetation phenology. Verification was also obtained to show that the seasonal variability in the reflected radiation anomalies, caused by the tropical deforestation, is associated with seasonal fluctuations in the precipitation anomalies. This study demonstrates that most of the spatial and seasonal variability in the simulated climate after a tropical deforestation can be explained by the difference in the radiation reflected by the surface. | |||||
BibTeX:
@article{berbert_climate_2003, author = {Berbert, M. L. C. and Costa, M. H.}, title = {Climate change after tropical deforestation: Seasonal variability of surface albedo and its effects on precipitation change}, journal = {Journal of Climate}, year = {2003}, volume = {16}, number = {12}, pages = {2099--2104}, url = {://WOS:000183460100016 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282003%29016%3C2099%3ACCATDS%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0442(2003)016%3C2099:ccatds%3E2.0.co;2} } |
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Bentos, T.V., Mesquita, R.C., Camargo, J.L. and Williamson, G.B. | Seed and fruit tradeoffs – the economics of seed packaging in Amazon pioneers [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 371-382 |
article | |
BibTeX:
@article{bentos_seed_2014, author = {Bentos, Tony V. and Mesquita, Rita C.G. and Camargo, José L.C. and Williamson, G. Bruce}, title = {Seed and fruit tradeoffs – the economics of seed packaging in Amazon pioneers}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {371--382} } |
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Benedetti, M., Ranville, J.F., Ponthieu, M. and Pinheiro, J.P. | Field-flow fractionation characterization and binding properties of particulate and colloidal organic matter from the Rio Amazon and Rio Negro | 2002 | Organic Geochemistry Vol. 33(3), pp. 269-279 |
article | DOI URL |
Abstract: Colloidal and particulate natural organic matter was fractionated and concentrated from the Amazon and Rio Negro rivers using tangential-flow filtration (TFF). Flow field-flow fractionation, with UV absorbance detection, was used to investigate the molecular weight distributions of the organic colloids. To further characterize the nature of the Rio Negro colloids, the size distributions of the iron and aluminum concentrations were determined by off-line graphite furnace atomic absorption spectrometry analysis of fractions collected during the FFF separation. The size distributions obtained by FFF were considerably smaller than expected from the stated pore size of the TFF membranes. These results demonstrate that care must be taken in using TFF to classify the size distribution of organic colloids and associated elements present in rivers. Total metal complexing capacities (TMCC) of the colloids were determined by voltametry at various pH using lead as a probe. Total binding capacities were measured by automated proton titration of the particulate and the colloidal fractions. To describe Pb binding together with Al competition and the presence of mineral forms of Al in the particulate fraction, the NICA-Donnan approach was used. The fitted model lines agree reasonably well with the experimental results, suggesting that natural ligands behave like purified humic or fulvic acids. This result is surprising due to the extreme treatment humic substances are subjected to during purification. The only major difference between the binding constant values obtained for purified humic substances and the TFF fractions is a higher affinity constant value for the carboxylic groups of the latter. An interesting result is the agreement in the metal binding for the different fractions at pH 4 and 5. which implies that the type of groups present in these fractions are similar. (C) 2002 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{benedetti_field-flow_2002, author = {Benedetti, M. and Ranville, J. F. and Ponthieu, M. and Pinheiro, J. P.}, title = {Field-flow fractionation characterization and binding properties of particulate and colloidal organic matter from the Rio Amazon and Rio Negro}, journal = {Organic Geochemistry}, year = {2002}, volume = {33}, number = {3}, pages = {269--279}, url = {://WOS:000174723200012 http://ac.els-cdn.com/S0146638001001590/1-s2.0-S0146638001001590-main.pdf?_tid=41744440-03f2-11e2-81a9-00000aab0f6b&acdnat=1348235159_a26086f8e0f35e2cf56164a7c6cfba7f}, doi = {https://doi.org/10.1016/s0146-6380(01)00159-0} } |
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Ben-Ami, Y., Koren, I., Rudich, Y., Artaxo, P., Martin, S.T. and Andreae, M.O. | Transport of North African dust from the Bod,l, depression to the Amazon Basin: a case study | 2010 | Atmospheric Chemistry and Physics Vol. 10(16), pp. 7533-7544 |
article | DOI URL |
Abstract: Through long-range transport of dust, the North-African desert supplies essential minerals to the Amazon rain forest. Since North African dust reaches South America mostly during the Northern Hemisphere winter, the dust sources active during winter are the main contributors to the forest. Given that the Bod,l, depression area in southwestern Chad is the main winter dust source, a close link is expected between the Bod,l, emission patterns and volumes and the mineral supply flux to the Amazon. Until now, the particular link between the Bod,l, and the Amazon forest was based on sparse satellite measurements and modeling studies. In this study, we combine a detailed analysis of space-borne and ground data with reanalysis model data and surface measurements taken in the central Amazon during the Amazonian Aerosol Characterization Experiment (AMAZE-08) in order to explore the validity and the nature of the proposed link between the Bod,l, depression and the Amazon forest. This case study follows the dust events of 11-16 and 18-27 February 2008, from the emission in the Bod,l, over West Africa (most likely with contribution from other dust sources in the region) the crossing of the Atlantic Ocean, to the observed effects above the Amazon canopy about 10 days after the emission. The dust was lifted by surface winds stronger than 14 m s(-1), usually starting early in the morning. The lofted dust, mixed with biomass burning aerosols over Nigeria, was transported over the Atlantic Ocean, and arrived over the South American continent. The top of the aerosol layer reached above 3 km, and the bottom merged with the boundary layer. The arrival of the dusty air parcel over the Amazon forest increased the average concentration of aerosol crustal elements by an order of magnitude. | |||||
BibTeX:
@article{ben-ami_transport_2010, author = {Ben-Ami, Y. and Koren, I. and Rudich, Y. and Artaxo, P. and Martin, S. T. and Andreae, M. O.}, title = {Transport of North African dust from the Bod,l, depression to the Amazon Basin: a case study}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {16}, pages = {7533--7544}, url = {://WOS:000281432800001 http://www.atmos-chem-phys.net/10/7533/2010/acp-10-7533-2010.pdf}, doi = {https://doi.org/10.5194/acp-10-7533-2010} } |
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Belk, E., Markewitz, D., Rasmussen, T., Carvalho, E.J.M., Nepstad, D. and Davidson, E. | Modeling the effects of throughfall reduction on soil water content in a Brazilian Oxisol under a moist tropical forest [BibTeX] |
2008 | Water Resources Research Vol. 44(7) |
article | DOI URL |
BibTeX:
@article{belk_modeling_2008, author = {Belk, E.L. and Markewitz, D. and Rasmussen, T.C. and Carvalho, E. J. M. and Nepstad, D.C. and Davidson, E.A.}, title = {Modeling the effects of throughfall reduction on soil water content in a Brazilian Oxisol under a moist tropical forest}, journal = {Water Resources Research}, year = {2008}, volume = {44}, number = {7}, url = {://WOS:000257436300002 http://www.agu.org/pubs/crossref/2008/2008WR007190.shtml}, doi = {https://doi.org/10.1029/2008wr007190} } |
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Belis, C.A., Karagulian, F., Amato, F., Almeida, M., Artaxo, P., Beddows, D., Bernardoni, V., Bove, M., Carbone, S., Cesari, D., Contini, D., Cuccia, E., Diapouli, E., Eleftheriadis, K., Favez, O. and al. , e. | A new methodology to assess the performance and uncertainty of source apportionment models II: The results of two European intercomparison exercises [BibTeX] |
2015 | Atmospheric Environment Vol. 123, pp. 240-250 |
article | DOI |
BibTeX:
@article{belis_new_2015, author = {Belis, C. A. and Karagulian, F. and Amato, F. and Almeida, M. and Artaxo, P. and Beddows, D.C.S. and Bernardoni, V. and Bove, M.C. and Carbone, S. and Cesari, D. and Contini, D. and Cuccia, E. and Diapouli, E. and Eleftheriadis, K. and Favez, O. and al., et}, title = {A new methodology to assess the performance and uncertainty of source apportionment models II: The results of two European intercomparison exercises}, journal = {Atmospheric Environment}, year = {2015}, volume = {123}, pages = {240--250}, doi = {https://doi.org/10.1016/j.atmosenv.2015.10.068} } |
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Belger, L., Forsberg, B.R. and Melack, J.M. | Carbon dioxide and methane emissions from interfluvial wetlands in the upper Negro River basin, Brazil | 2011 | Biogeochemistry Vol. 105(1-3), pp. 171-183 |
article | DOI URL |
Abstract: Extensive interfluvial wetlands occur in the upper Negro River basin (Brazil) and contain a mosaic of vegetation dominated by emergent grasses and sedges with patches of shrubs and palms. To characterize the release of carbon dioxide and methane from these habitats, diffusive and ebullitive emissions and transport through plant aerenchyma were measured monthly during 2005 in permanently and seasonally flooded areas. CO(2) emissions averaged 2193 mg C m(-2) day(-1). Methane was consumed in unflooded environments and emitted in flooded environments with average values of -4.8 and 60 mg C m(-2) day(-1), respectively. Bubbles were emitted primarily during falling water periods when hydrostatic pressure at the sediment-water interface declined. CO(2) and CH(4) emissions increased when dissolved O(2) decreased and vegetation was more abundant. Total area and seasonally varying flooded areas for two wetlands, located north and south of the Negro River, were determined through analysis of synthetic aperture radar and optical remotely sensed data. The combined areas of these two wetlands (3000 km(2)) emitted 1147 Gg C year(-1) as CO(2) and 31 Gg C year(-1) as CH(4). If these rates are extrapolated to the area occupied by hydromorphic soils in the upper Negro basin, 63 Tg C year(-1) of CO(2) and 1.7 Tg C year(-1) as CH(4) are estimated as the regional evasion to the atmosphere. | |||||
BibTeX:
@article{belger_carbon_2011, author = {Belger, L. and Forsberg, B. R. and Melack, J. M.}, title = {Carbon dioxide and methane emissions from interfluvial wetlands in the upper Negro River basin, Brazil}, journal = {Biogeochemistry}, year = {2011}, volume = {105}, number = {1-3}, pages = {171--183}, url = {://000294501100013 http://www.springerlink.com/content/y24604wl4t046h43/fulltext.pdf}, doi = {https://doi.org/10.1007/s10533-010-9536-0} } |
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Beldini, T.P., Silva, R.d., Valente, F.C.P. and Fitzjarrald, D. | Characterization of interannual and seasonal patterns and extremes in 41 years of precipitation data from Belterra, Pará, Brazil [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 329 - 333 |
article | |
BibTeX:
@article{beldini_characterization_2013, author = {Beldini, Troy Patrick and Silva, Rodrigo da and Valente, Fabíola Carolina Pereira and Fitzjarrald, David}, title = {Characterization of interannual and seasonal patterns and extremes in 41 years of precipitation data from Belterra, Pará, Brazil}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {329 -- 333} } |
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Beldini, T.B., Oliveira Junior, R.C.d., Keller, M.M., Camargo, P.B.d., Crill, P.M., Silva, A.D.d., Santos, D.B.d. and Oliveira, D.R.d. | Physical, chemical, and biological properties of soil under soybean cultivation and at an adjacent rainforest in Amazonia. [BibTeX] |
2015 | Ambiente & Água: An Interdisciplinary Journal of Applied Ecology Vol. 10(4), pp. 707-719 |
article | |
BibTeX:
@article{beldini_physical_2015, author = {Beldini, T. B. and Oliveira Junior, R. C. de and Keller, M. M. and Camargo, P. B. de and Crill, P. M. and Silva, A. D. da and Santos, D. B. dos and Oliveira, D. R. de.}, title = {Physical, chemical, and biological properties of soil under soybean cultivation and at an adjacent rainforest in Amazonia.}, journal = {Ambiente & Água: An Interdisciplinary Journal of Applied Ecology}, year = {2015}, volume = {10}, number = {4}, pages = {707--719} } |
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Bela, M.M., Longo, K.M., Freitas, S.R., Moreira, D.S., Beck, V., Wofsy, S.C., Gerbig, C., Wiedemann, K., Andreae, M.O. and Artaxo, P. | Ozone production and transport over the Amazon Basin during the dry-to-wet and wet-to-dry transition seasons [BibTeX] |
2015 | Atmospheric Chemistry and Physics Vol. 15, pp. 757-782 |
article | |
BibTeX:
@article{bela_ozone_2015, author = {Bela, M. M. and Longo, K. M. and Freitas, S. R. and Moreira, D. S. and Beck, V. and Wofsy, S. C. and Gerbig, C. and Wiedemann, K. and Andreae, M. O. and Artaxo, P.}, title = {Ozone production and transport over the Amazon Basin during the dry-to-wet and wet-to-dry transition seasons}, journal = {Atmospheric Chemistry and Physics}, year = {2015}, volume = {15}, pages = {757--782} } |
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Becker, B.K. | Pensando no Futuro da Amazônia: O Papel das Cidades em Produzir para Conservar [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 277-289 |
incollection | |
BibTeX:
@incollection{batistella_pensando_2008, author = {Becker, Bertha K.}, title = {Pensando no Futuro da Amazônia: O Papel das Cidades em Produzir para Conservar}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {277--289}, note = {Section: 3} } |
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Beck B., H.C.C.G.P.B.L.B.S.H.T.R.O.K.J.S.C.J.S.C.v.d.V.C.F.T.K.M.O.A.P.A.K.M.L.S.C.W.V. | Methane airborne measurements and comparison to global models during BARCA [BibTeX] |
2012 | Journal of Geophysical Research Vol. 117(D15310), pp. 15310-15326 |
article | DOI |
BibTeX:
@article{beck_methane_2012, author = {Beck, B., H. Chen, C. Gerbig, P. Bergamaschi, L. Bruhwiler, S. Houweling, T. Röckmann, O. Kolle, J. Steinbach, C. J. Sapart, C. van der Veen, C. Frankenberg, T. Koch, M. O. Andreae, P. Artaxo, K. M. Longo, S. C. Wofsy., V.}, title = {Methane airborne measurements and comparison to global models during BARCA}, journal = {Journal of Geophysical Research}, year = {2012}, volume = {117}, number = {D15310}, pages = {15310--15326}, doi = {https://doi.org/10.1029/2011JD017345} } |
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Bechtold, P., Chaboureau, J.P., Beljaars, A., Betts, A.K., Kohler, M., Miller, M. and Redelsperger, J.L. | The simulation of the diurnal cycle of convective precipitation over land in a global model | 2004 | Quarterly Journal of the Royal Meteorological Society Vol. 130(604), pp. 3119-3137 |
article | DOI URL |
Abstract: In the context of the European Cloud Systems project, the problem of the simulation of the diurnal cycle of convective precipitation over land is addressed with the aid of cloud-resolving (CRM) and single-column (SCM) model simulations of an idealized midlatitude case for which observations of large-scale and surface forcing are available. The CRM results are compared to different versions of the European Centre for Medium-Range Weather Forecasts (ECMWF) convection schemes using different convective trigger procedures and convective closures. In the CRM, maximum rainfall intensity occurs at 15 h (local time). In this idealized midlatitude case, most schemes do not reproduce the afternoon precipitation peak, as (i) they cannot reproduce the gradual growth (typically over 3 hours) of the deep convective cloud layer and (ii) they produce a diurnal cycle of precipitation that is in phase with the diurnal cycle of the convective available potential energy (CAPE) and the convective inhibition (CIN), consistent with the parcel theory and CAPE closure used in the bulk mass-flux scheme. The scheme that links the triggering to the large-scale vertical velocity gets the maximum precipitation at the right time, but this may be artificial as the vertical velocity is enforced in the single-column context. The study is then extended to the global scale using ensembles of 72-hour global forecasts at resolution T511 (40 km), and long-range single 40-day forecasts at resolution T 159 (125 km) with the ECMWF general-circulation model. The focus is on tropical South America and Africa where the diurnal cycle is most pronounced. The forecasts are evaluated against analyses and observed radiosonde data, as well as observed surface and satellite-derived rainfall rates. The ECMWF model version with improved convective trigger produces the smallest biases overall. It also shifts the rainfall maximum to 12 It compared to 9.5 h in the original version. In contrast to the SCM, the vertical-velocity-dependent trigger does not further improve the phase of the diurnal cycle. However. further work is necessary to match the observed 15 h precipitation peak. |
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BibTeX:
@article{bechtold_simulation_2004, author = {Bechtold, P. and Chaboureau, J. P. and Beljaars, A. and Betts, A. K. and Kohler, M. and Miller, M. and Redelsperger, J. L.}, title = {The simulation of the diurnal cycle of convective precipitation over land in a global model}, journal = {Quarterly Journal of the Royal Meteorological Society}, year = {2004}, volume = {130}, number = {604}, pages = {3119--3137}, url = {://WOS:000226878300005 http://onlinelibrary.wiley.com/store/10.1256/qj.03.103/asset/200413060404_ftp.pdf?v=1&t=h6hxlctx&s=2c6f993f494ee67a160e05f9f4a79a5ea2bda721}, doi = {https://doi.org/10.1256/qj.03.103} } |
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Bauch, S.C., Amacher, G.S. and Merry, F.D. | Costs of harvesting, transportation and milling in the Brazilian Amazon: Estimation and policy implications | 2007 | Forest Policy and Economics Vol. 9(8), pp. 903-915 |
article | DOI URL |
Abstract: We estimate economic cost functions for timber harvesting, transportation and milling in the Brazilian Amazon using a 2003 sample of 527 firms in both new and older frontier locations. We find that labor wage, distance from the forest to the processing location, type of equipment, and the type of the frontier all factor significantly in the total and marginal cost of each activity, and that predicted processing costs are not significantly different on new frontiers implying a lack of technology adoption as industry expansion into the Amazon has occurred. We also show that capturing economies of scale in logging by increasing average annual logging volumes by 50% and reducing the number of firms to about 1400 could lead to an industry wide cost savings of approximately US$90 million per year. Similar economies of scale are also present in log transport but not in processing. Further, if improved logging techniques allow harvest for an additional I month per year, for example through better planning, the industry could reduce logging costs by almost US$30 million. This points towards generating forest policies and economic conditions that encourage firm size growth, as opposed to those policies encouraging massive entry of small, unregulated and inefficient firms, and the adoption of management practices that allow for additional time in the forest. (C) 2006 Published by Elsevier B.V. | |||||
BibTeX:
@article{bauch_costs_2007, author = {Bauch, Simone C. and Amacher, Gregory S. and Merry, Frank D.}, title = {Costs of harvesting, transportation and milling in the Brazilian Amazon: Estimation and policy implications}, journal = {Forest Policy and Economics}, year = {2007}, volume = {9}, number = {8}, pages = {903--915}, url = {://WOS:000246970400002 http://ac.els-cdn.com/S1389934106000906/1-s2.0-S1389934106000906-main.pdf?_tid=3c1779b8-03f2-11e2-8771-00000aab0f02&acdnat=1348235152_e2543a4e5db8d464fe8c298324a48cc4}, doi = {https://doi.org/10.1016/j.forpol.2006.07.004} } |
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Batistella, M., Robeson, S. and Moran, E.F. | Settlement design, forest fragmentation, and landscape change in Rondonia, Amazonia | 2003 | Photogrammetric Engineering and Remote Sensing Vol. 69(7), pp. 805-812 |
article | URL |
Abstract: Deforestation and colonization in Amazonia have attracted substantial attention. This article focuses on an area of 3,000 km(2) within the Brazilian State of Rondonia. Two adjacent settlements were compared to assess the role of their different designs in landscape change. Anari was planned following an orthogonal road network. Machadinho was designed with attention to topography in laying out roads and farm properties, while including communal reserves. Field research was undertaken in conjunction with multi-temporal classifications of remotely sensed data (1988, 1994, and 1998) and landscape ecology methods, The results indicate that large patches of communal reserves play an important role in maintaining lower levels of fragmentation. Analyses of landscape structure confirmed that forest patches in Machadinho are less fragmented, more complex, and preserve more interior habitat. By comparing the effects of different settlement designs on landscape change and forest fragmentation, this article contributes to the debate about colonization strategies in Amazonia. | |||||
BibTeX:
@article{batistella_settlement_2003, author = {Batistella, M. and Robeson, S. and Moran, E. F.}, title = {Settlement design, forest fragmentation, and landscape change in Rondonia, Amazonia}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2003}, volume = {69}, number = {7}, pages = {805--812}, url = {://WOS:000221193600007} } |
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Batistella, M., Moran, E.F. and Alves, D. | Prefácio- Abordagens Interdisciplinares na Ciência Amazônica: A Contribuição do LBA e Outras Perspectivas [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 7-12 |
incollection | |
BibTeX:
@incollection{batistella_prefacio-_2008, author = {Batistella, Mateus and Moran, Emilio F and Alves, Diogenes}, title = {Prefácio- Abordagens Interdisciplinares na Ciência Amazônica: A Contribuição do LBA e Outras Perspectivas}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {7--12}, note = {Section: 1} } |
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Batistella, M., Moran, E.F. and Alves, D. | Amazônia: Natureza e Sociedade em Transformação. [BibTeX] |
2008 | Vol. 1(1) |
book | |
BibTeX:
@book{batistella_amazonia_2008, author = {Batistella, Mateus and Moran, Emilio F. and Alves, Diogenes}, title = {Amazônia: Natureza e Sociedade em Transformação.}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1} } |
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Batistella, M. and Moran, E. | Dimensões humanas do uso e cobertura das terras na Amazônia: uma contribuição do LBA [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 239-247 |
article | |
BibTeX:
@article{batistella_dimensoes_2005, author = {Batistella, M. and Moran, E.F.}, title = {Dimensões humanas do uso e cobertura das terras na Amazônia: uma contribuição do LBA}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {239--247} } |
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Batistella, M., Alves, D., Moran, E., Souza Jr., C., Walker, R. and Walsh, S. | People and Environment in Amazonia: The LBA Experience and Other Perspectives [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change |
incollection | |
BibTeX:
@incollection{m_keller_people_2009, author = {Batistella, M. and Alves, D.S. and Moran, E.F. and Souza Jr., C. and Walker, R. and Walsh, S.}, title = {People and Environment in Amazonia: The LBA Experience and Other Perspectives}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186} } |
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Batistella P. Artaxo, C.N.M.B.F. and Luizão., M. | Results From LBA and a Vision for Future Amazonian Research [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 555-564 |
incollection | |
BibTeX:
@incollection{m_keller_results_2009, author = {Batistella, P. Artaxo, C. Nobre, M. Bustamante, F; Luizão., M.}, title = {Results From LBA and a Vision for Future Amazonian Research}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {555--564} } |
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Batista, E. and Schöngart, J. | Dendroecology of Macrolobium acaciifolium (Fabaceae) in Central Amazonian floodplain forests [BibTeX] |
2018 | Acta Amazonica Vol. 48, pp. 311-320 |
article | DOI |
BibTeX:
@article{batista_dendroecology_2018, author = {Batista, E.S. and Schöngart, J.}, title = {Dendroecology of Macrolobium acaciifolium (Fabaceae) in Central Amazonian floodplain forests}, journal = {Acta Amazonica}, year = {2018}, volume = {48}, pages = {311--320}, doi = {https://doi.org/10.1590/1809-4392201800302} } |
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Bateman, A.P., Gong, Z., Liu, P., Sato, B., Cirino, G., Zhang, Y., Artaxo, P., Bertram, A.K., Manzi, A.O., Rizzo, L.V., Souza, R.A.F., Zaveri, R.A. and Martin, S.T. | Sub-micrometre particulate matter is primarily in liquid form over Amazon rainforest [BibTeX] |
2015 | Nature Geosciences Vol. 9, pp. 34-37 |
article | DOI |
BibTeX:
@article{bateman_sub-micrometre_2015, author = {Bateman, Adam P. and Gong, Zhaoheng and Liu, Pengfei and Sato, Bruno and Cirino, Glauber and Zhang, Yue and Artaxo, Paulo and Bertram, Allan K. and Manzi, Antonio O. and Rizzo, Luciana V. and Souza, Rodrigo A. F. and Zaveri, Rahul A. and Martin, Scot T.}, title = {Sub-micrometre particulate matter is primarily in liquid form over Amazon rainforest}, journal = {Nature Geosciences}, year = {2015}, volume = {9}, pages = {34--37}, doi = {https://doi.org/10.1038/NGEO2599} } |
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Bateman Gong, Z.H.T.H.d.S.S.S.W.B.C.P.C.S.L.Y.O.R.E.P.B.S.H.-W.d.S.G.T.R.A.K.A.M.L.A.P.B.A.K.B.P.R.G.M.K.J.J.L.L.A.M.A.O.S.A.S.R.A.F.W.J.Z.R.and.M.S.T.A.P. | Anthropogenic influences on the physical state of submicron particulate matter over a tropical forest [BibTeX] |
2017 | Atmos. Chem. Phys. Vol. 17, pp. 1759-1773 |
article | DOI |
BibTeX:
@article{bateman_anthropogenic_2017, author = {Bateman, Gong, Z., Harder, T. H., de Sá, S. S., Wang, B., Castillo, P., China, S., Liu, Y., O'Brien, R. E., Palm, B., Shiu, H.-W., da Silva, G., Thalman, R., Adachi, K., Alexander, M. L., Artaxo, P., Bertram, A. K., Buseck, P. R., Gilles, M. K., Jimenez, J. L., Laskin, A., Manzi, A. O., Sedlacek, A., Souza, R. A. F., Wang, J., Zaveri, R., and Martin, S. T., A. P.}, title = {Anthropogenic influences on the physical state of submicron particulate matter over a tropical forest}, journal = {Atmos. Chem. Phys.}, year = {2017}, volume = {17}, pages = {1759--1773}, doi = {https://doi.org/10.5194/acp-17-1759-2017} } |
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Basso, L.S., Gatti, L.V., Gloor, M., Miller, J.B., Domingues, L.G., Correia, C.S.C. and Borges, V.F. | Seasonality and interannual variability of CH4 fluxes from the eastern Amazon Basin inferred from atmospheric mole fraction profiles [BibTeX] |
2016 | Jornal of Geophysical Research: Atmospheres Vol. 121(1), pp. 168-184 |
article | DOI |
BibTeX:
@article{basso_seasonality_2016, author = {Basso, Luana S. and Gatti, Luciana V. and Gloor, Manuel and Miller, John B. and Domingues, Lucas G. and Correia, Caio S. C. and Borges, Viviane F.}, title = {Seasonality and interannual variability of CH4 fluxes from the eastern Amazon Basin inferred from atmospheric mole fraction profiles}, journal = {Jornal of Geophysical Research: Atmospheres}, year = {2016}, volume = {121}, number = {1}, pages = {168--184}, doi = {https://doi.org/10.1002/2015JD023874} } |
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Bäse, F., Elsenbeer, H., Neill, C. and Krusche, A. | Differences in throughfall and net precipitation between soybean and transitional tropical forest in the southern Amazon, Brazil. [BibTeX] |
2012 | Agriculture, Ecosystems & Environment Vol. 159, pp. 19- 28. |
article | |
BibTeX:
@article{base_differences_2012, author = {Bäse, F. and Elsenbeer, H. and Neill, C. and Krusche, A.V.}, title = {Differences in throughfall and net precipitation between soybean and transitional tropical forest in the southern Amazon, Brazil.}, journal = {Agriculture, Ecosystems & Environment}, year = {2012}, volume = {159}, pages = {19-- 28.} } |
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Bartholomew, D.C., Bittencourt, P.R.L., da Costa, A.C.L., Banin, L.F., de Britto Costa, P., Coughlin, S.I., Domingues, T.F., Ferreira, L.V., Giles, A., Mencuccini, M., Mercado, L., Miatto, R.C., Oliveira, A., Oliveira, R., Meir, P. and Rowland, L. | Small tropical forest trees have a greater capacity to adjust carbon metabolism to long-term drought than large canopy trees | 2020 | Plant, Cell & Environment Vol. 43(10), pp. 2380-2393 |
article | DOI URL |
Abstract: Abstract The response of small understory trees to long-term drought is vital in determining the future composition, carbon stocks and dynamics of tropical forests. Long-term drought is, however, also likely to expose understory trees to increased light availability driven by drought-induced mortality. Relatively little is known about the potential for understory trees to adjust their physiology to both decreasing water and increasing light availability. We analysed data on maximum photosynthetic capacity (Jmax, Vcmax), leaf respiration (Rleaf), leaf mass per area (LMA), leaf thickness and leaf nitrogen and phosphorus concentrations from 66 small trees across 12 common genera at the world's longest running tropical rainfall exclusion experiment and compared responses to those from 61 surviving canopy trees. Small trees increased Jmax, Vcmax, Rleaf and LMA (71, 29, 32, 15% respectively) in response to the drought treatment, but leaf thickness and leaf nutrient concentrations did not change. Small trees were significantly more responsive than large canopy trees to the drought treatment, suggesting greater phenotypic plasticity and resilience to prolonged drought, although differences among taxa were observed. Our results highlight that small tropical trees have greater capacity to respond to ecosystem level changes and have the potential to regenerate resilient forests following future droughts. | |||||
BibTeX:
@article{bartholomew_small_2020, author = {Bartholomew, David C. and Bittencourt, Paulo R. L. and da Costa, Antonio C. L. and Banin, Lindsay F. and de Britto Costa, Patrícia and Coughlin, Sarah I. and Domingues, Tomas F. and Ferreira, Leandro V. and Giles, André and Mencuccini, Maurizio and Mercado, Lina and Miatto, Raquel C. and Oliveira, Alex and Oliveira, Rafael and Meir, Patrick and Rowland, Lucy}, title = {Small tropical forest trees have a greater capacity to adjust carbon metabolism to long-term drought than large canopy trees}, journal = {Plant, Cell & Environment}, year = {2020}, volume = {43}, number = {10}, pages = {2380--2393}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/pce.13838}, doi = {https://doi.org/10.1111/pce.13838} } |
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Kruijt, B., Johnson, M., Rammig, A., Fauset, S., Baker, T. and Meir, P. | Modelling Amazonian Carbon Budgets and Vegetation Dynamics in a Changing Climate [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 331-366 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_modelling_2016, author = {Bart Kruijt, Michelle Johnson, Anja Rammig, Sophie Fauset, Tim Baker, Patrick Meir}, title = {Modelling Amazonian Carbon Budgets and Vegetation Dynamics in a Changing Climate}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {331--366}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Barros, F.d.V., Bittencourt, P.R.L., Brum, M., Restrepo‐Coupe, N., Pereira, L., Teodoro, G.S., Saleska, S.R., Borma, L.S., Christoffersen, B.O., Penha, D., Alves, L.F., Lima, A.J.N., Carneiro, V.M.C., Gentine, P., Lee, J., Aragão, L.E.O.C., Ivanov, V., Leal, L.S.M., Araujo, A.C. and Oliveira, R.S. | Hydraulic traits explain differential responses of Amazonian forests to the 2015 El Niño‐induced drought [BibTeX] |
2019 | New Phytologist Vol. 223(3), pp. 1253-1266 |
article | DOI |
BibTeX:
@article{barros_hydraulic_2019, author = {Barros, F. de V. and Bittencourt, P. R. L. and Brum, Mauro and Restrepo‐Coupe, Natalia and Pereira, Luciano and Teodoro, Grazielle S. and Saleska, Scott R. and Borma, Laura S. and Christoffersen, Bradley O. and Penha, Deliane and Alves, Luciana F. and Lima, Adriano J. N. and Carneiro, Vilany M. C. and Gentine, Pierre and Lee, Jung‐Eun and Aragão, Luiz E. O. C. and Ivanov, Valeriy and Leal, Leila S. M. and Araujo, Alessandro C. and Oliveira, Rafael S.}, title = {Hydraulic traits explain differential responses of Amazonian forests to the 2015 El Niño‐induced drought}, journal = {New Phytologist}, year = {2019}, volume = {223}, number = {3}, pages = {1253--1266}, doi = {https://doi.org/10.1111/nph.15909} } |
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Barretto, S., R.B.C., R., Nunes, R.S., H.G.C., S. and P. N., E.B. | Influência do El Niño e La Niña nos campos de precipitação e temperatura na Reserva de Caxiuanã, PA - Amazônia Oriental [BibTeX] |
2009 | Revista Ciência e Natura Vol. Edição Especial em Micrometeorologia, pp. 337-340 |
article | |
BibTeX:
@article{barretto_influencia_2009, author = {Barretto, Silva, R.B.C., Rodrigues, R.S., Nunes, H.G.C., Souza, E.B., P. N.}, title = {Influência do El Niño e La Niña nos campos de precipitação e temperatura na Reserva de Caxiuanã, PA - Amazônia Oriental}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Edição Especial em Micrometeorologia}, pages = {337--340} } |
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Barreto, J.R., Berenguer, E., Ferreira, J., Joly, C.A., Malhi, Y., de Seixas, M.M.M. and Barlow, J. | Assessing invertebrate herbivory in human-modified tropical forest canopies | 2021 | Ecology and Evolution Vol. 11(9), pp. 4012-4022 |
article | DOI URL |
Abstract: Abstract Studies on the effects of human-driven forest disturbance usually focus on either biodiversity or carbon dynamics but much less is known about ecosystem processes that span different trophic levels. Herbivory is a fundamental ecological process for ecosystem functioning, but it remains poorly quantified in human-modified tropical rainforests. Here, we present the results of the largest study to date on the impacts of human disturbances on herbivory. We quantified the incidence (percentage of leaves affected) and severity (the percentage of leaf area lost) of canopy insect herbivory caused by chewers, miners, and gall makers in leaves from 1,076 trees distributed across 20 undisturbed and human-modified forest plots in the Amazon. We found that chewers dominated herbivory incidence, yet were not a good predictor of the other forms of herbivory at either the stem or plot level. Chewing severity was higher in both logged and logged-and-burned primary forests when compared to undisturbed forests. We found no difference in herbivory severity between undisturbed primary forests and secondary forests. Despite evidence at the stem level, neither plot-level incidence nor severity of the three forms of herbivory responded to disturbance. Synthesis. Our large-scale study of canopy herbivory confirms that chewers dominate the herbivory signal in tropical forests, but that their influence on leaf area lost cannot predict the incidence or severity of other forms. We found only limited evidence suggesting that human disturbance affects the severity of leaf herbivory, with higher values in logged and logged-and-burned forests than undisturbed and secondary forests. Additionally, we found no effect of human disturbance on the incidence of leaf herbivory. | |||||
BibTeX:
@article{barreto_assessing_2021, author = {Barreto, Julia Rodrigues and Berenguer, Erika and Ferreira, Joice and Joly, Carlos A. and Malhi, Yadvinder and de Seixas, Marina Maria Moraes and Barlow, Jos}, title = {Assessing invertebrate herbivory in human-modified tropical forest canopies}, journal = {Ecology and Evolution}, year = {2021}, volume = {11}, number = {9}, pages = {4012--4022}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/ece3.7295}, doi = {https://doi.org/10.1002/ece3.7295} } |
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Barni, P.E., Pereira, V.B., Manzi, A. and Barbosa, R.I. | Deforestation and Forest Fires in Roraima and Their Relationship with Phytoclimatic Regions in the Northern Brazilian Amazon [BibTeX] |
2015 | Environmental Management Vol. 55, pp. 1124-1138 |
article | |
BibTeX:
@article{barni_deforestation_2015, author = {Barni, P. E. and Pereira, V. B. and Manzi, A.O. and Barbosa, R. I.}, title = {Deforestation and Forest Fires in Roraima and Their Relationship with Phytoclimatic Regions in the Northern Brazilian Amazon}, journal = {Environmental Management}, year = {2015}, volume = {55}, pages = {1124--1138} } |
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Barlow, J., Lennox, G.D., Ferreira, J., Berenguer, E., Lees, A.C., Nally, R.M., Thomson, J.R., Ferraz, S.F.d.B., Louzada, J., Oliveira, V.H.F., Parry, L., Solar, R.R.d.C., Vieira, I.C.G., Aragão, L.E.O.C., Begotti, R.A., Braga, R.F., Cardoso, T.M., Oliveira Jr, R.C.d., Souza Jr, C.M., Moura, N.G., Nunes, S.S., Siqueira, J.V., Pardini, R., Silveira, J.M., Vaz-de-Mello, F.Z. and al. , e. | Anthropogenic disturbance in tropical forests can double biodiversity loss from deforestation [BibTeX] |
2016 | Nature | article | DOI |
BibTeX:
@article{barlow_anthropogenic_2016, author = {Barlow, Jos and Lennox, Gareth D. and Ferreira, Joice and Berenguer, Erika and Lees, Alexander C. and Nally, Ralph Mac and Thomson, James R. and Ferraz, Silvio Frosini de Barros and Louzada, Julio and Oliveira, Victor Hugo Fonseca and Parry, Luke and Solar, Ricardo Ribeiro de Castro and Vieira, Ima C. G. and Aragão, Luiz E. O. C. and Begotti, Rodrigo Anzolin and Braga, Rodrigo F. and Cardoso, Thiago Moreira and Oliveira Jr, Raimundo Cosme de and Souza Jr, Carlos M. and Moura, Nárgila G. and Nunes, Sâmia Serra and Siqueira, João Victor and Pardini, Renata and Silveira, Juliana M. and Vaz-de-Mello, Fernando Z. and al., et}, title = {Anthropogenic disturbance in tropical forests can double biodiversity loss from deforestation}, journal = {Nature}, year = {2016}, doi = {https://doi.org/10.1038/nature18326} } |
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Barlow, J., França, F., Gardner, T., Hicks, C.C., Lennox, G., Berenguer, E., Castello, L., Economo, E.P., Ferreira, J., Guénard, B., Leal, C., Isaac, V., Lees, A.C., Parr, C.L., Wilson, S.K., Young, P.J. and Graham, N.A.J. | The future of hyperdiverse tropical ecosystems [BibTeX] |
2018 | Nature Vol. 559, pp. 517-526 |
article | |
BibTeX:
@article{barlow_future_2018, author = {Barlow, J. and França, F. and Gardner, T.A. and Hicks, C. C. and Lennox, G.D. and Berenguer, E. and Castello, L. and Economo, E. P. and Ferreira, J. and Guénard, B. and Leal, C.G. and Isaac, V. and Lees, A. C. and Parr, Catherine L. and Wilson, Shaun K. and Young, Paul J. and Graham, Nicholas A. J.}, title = {The future of hyperdiverse tropical ecosystems}, journal = {Nature}, year = {2018}, volume = {559}, pages = {517--526} } |
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Barlow, J., Ewers, R.M., Anderson, L., Aragao, L.E.O.C., Baker, T.R., Boyd, E., Feldpausch, T.R., Gloor, E., Hall, A., Malhi, Y., Milliken, W., Mulligan, M., Parry, L., Pennington, T., Peres, C.A., Phillips, O.L., Roman-Cuesta, R.M., Tobias, J.A. and Gardner, T.A. | Using learning networks to understand complex systems: a case study of biological, geophysical and social research in the Amazon | 2011 | Biological Reviews Vol. 86(2), pp. 457-474 |
article | DOI URL |
Abstract: Developing high-quality scientific research will be most effective if research communities with diverse skills and interests are able to share information and knowledge, are aware of the major challenges across disciplines, and can exploit economies of scale to provide robust answers and better inform policy. We evaluate opportunities and challenges facing the development of a more interactive research environment by developing an interdisciplinary synthesis of research on a single geographic region. We focus on the Amazon as it is of enormous regional and global environmental importance and faces a highly uncertain future. To take stock of existing knowledge and provide a framework for analysis we present a set of mini-reviews from fourteen different areas of research, encompassing taxonomy, biodiversity, biogeography, vegetation dynamics, landscape ecology, earth-atmosphere interactions, ecosystem processes, fire, deforestation dynamics, hydrology, hunting, conservation planning, livelihoods, and payments for ecosystem services. Each review highlights the current state of knowledge and identifies research priorities, including major challenges and opportunities. We show that while substantial progress is being made across many areas of scientific research, our understanding of specific issues is often dependent on knowledge from other disciplines. Accelerating the acquisition of reliable and contextualized knowledge about the fate of complex pristine and modified ecosystems is partly dependent on our ability to exploit economies of scale in shared resources and technical expertise, recognise and make explicit interconnections and feedbacks among sub-disciplines, increase the temporal and spatial scale of existing studies, and improve the dissemination of scientific findings to policy makers and society at large. Enhancing interaction among research efforts is vital if we are to make the most of limited funds and overcome the challenges posed by addressing large-scale interdisciplinary questions. Bringing together a diverse scientific community with a single geographic focus can help increase awareness of research questions both within and among disciplines, and reveal the opportunities that may exist for advancing acquisition of reliable knowledge. This approach could be useful for a variety of globally important scientific questions. | |||||
BibTeX:
@article{barlow_using_2011, author = {Barlow, Jos and Ewers, Robert M. and Anderson, Liana and Aragao, Luiz E. O. C. and Baker, Tim R. and Boyd, Emily and Feldpausch, Ted R. and Gloor, Emanuel and Hall, Anthony and Malhi, Yadvinder and Milliken, William and Mulligan, Mark and Parry, Luke and Pennington, Toby and Peres, Carlos A. and Phillips, Oliver L. and Roman-Cuesta, Rosa Maria and Tobias, Joseph A. and Gardner, Toby A.}, title = {Using learning networks to understand complex systems: a case study of biological, geophysical and social research in the Amazon}, journal = {Biological Reviews}, year = {2011}, volume = {86}, number = {2}, pages = {457--474}, note = {Edition: 2010/09/21}, url = {://WOS:000289486700010 http://onlinelibrary.wiley.com/store/10.1111/j.1469-185X.2010.00155.x/asset/j.1469-185X.2010.00155.x.pdf?v=1&t=h6hxl0rx&s=202c47d81e419de843fe7a7e427c3ff7ef83df63}, doi = {https://doi.org/10.1111/j.1469-185X.2010.00155.x} } |
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Barford, C.C., Wofsy, S.C., Goulden, M.L., Munger, J.W., Pyle, E.H., Urbanski, S.P., Hutyra, L., Saleska, S.R., Fitzjarrald, D. and Moore, K. | Factors controlling long- and short-term sequestration of atmospheric CO2 in a mid-latitude forest | 2001 | Science Vol. 294(5547), pp. 1688-1691 |
article | DOI URL |
Abstract: Net uptake of carbon dioxide (CO2) measured by eddy covariance in a 60- to 80-year-old forest averaged 2.0 +/- 0.4 megagrams of carbon per hectare per year during 1993 to 2000, with interannual variations exceeding 50%. Biometry indicated storage of 1.6 +/- 0.4 megagrams of carbon per hectare per year over 8 years, 60% in Live biomass and the balance in coarse woody debris and soils, confirming eddy-covariance results. Weather and seasonal climate (e.g., variations in growing-season length or cloudiness) regulated seasonal and interannual fluctuations of carbon uptake. Legacies of prior disturbance and management, especially stand age and composition, controlled carbon uptake on the decadal time scale, implying that eastern forests could be managed for Sequestration of carbon. | |||||
BibTeX:
@article{barford_factors_2001, author = {Barford, C. C. and Wofsy, S. C. and Goulden, M. L. and Munger, J. W. and Pyle, E. H. and Urbanski, S. P. and Hutyra, L. and Saleska, S. R. and Fitzjarrald, D. and Moore, K.}, title = {Factors controlling long- and short-term sequestration of atmospheric CO2 in a mid-latitude forest}, journal = {Science}, year = {2001}, volume = {294}, number = {5547}, pages = {1688--1691}, note = {Edition: 2001/11/27}, url = {://WOS:000172307400035 http://www.sciencemag.org/content/294/5547/1688}, doi = {https://doi.org/10.1126/science.1062962} } |
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Barcellos, C., Monteiro, A., Corvalán, C., Gurgel, H., Carvalho, M., Artaxo, P., Hacon, S. and Ragoni, V. | Mudanças climáticas e ambientais e as doenças infecciosas: cenários e incertezas para o Brasil [BibTeX] |
2009 | Epidemiologia e Serviços de Saúde Vol. 18(3), pp. 285-304 |
article | |
BibTeX:
@article{barcellos_mudancas_2009, author = {Barcellos, C. and Monteiro, A.M.V. and Corvalán, C. and Gurgel, H.C. and Carvalho, M.S. and Artaxo, P. and Hacon, S. and Ragoni, V.}, title = {Mudanças climáticas e ambientais e as doenças infecciosas: cenários e incertezas para o Brasil}, journal = {Epidemiologia e Serviços de Saúde}, year = {2009}, volume = {18}, number = {3}, pages = {285--304} } |
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Barbosa, R.I. and Fearnside, P.M. | Fire frequency and area burned in the Roraima savannas of Brazilian Amazonia | 2005 | Forest Ecology and Management Vol. 204(2-3), pp. 371-384 |
article | DOI URL |
Abstract: Estimates were made of the percentage of area burned and the fire frequency in different ecosystems of non-anthropic savannas located in the north and northeast portions of the State of Roraima. Brazil. Three years of observations (June 1997-May 2000) indicated that the mean percentage of area burned annually, weighted for all ecosystems. was 38 +/- 12% (S.D.). The mean frequency of fire (number of years for an area to burn again) was 2.5 years. Both parameters are dependent on the type (structure) of vegetation, the altitude of the savanna and the climatic state (dray. wet or normal) of the year of the observation. Using values for 2-month periods over the 3-year time series (n = 18), a simple regression model was developed to forecast percentage area burned for grassy-woody savanna ("clean field" and "dirty field" types). using as the independent variable the mean precipitation in each 2-month period. The proposed model explains 66% of the reported cases. These results are the first developed for savannas in the Amazon region and are directly applicable to calculations of greenhouse-gas emissions from burning in this ecosystem type. (C) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{barbosa_fire_2005, author = {Barbosa, R. I. and Fearnside, P. M.}, title = {Fire frequency and area burned in the Roraima savannas of Brazilian Amazonia}, journal = {Forest Ecology and Management}, year = {2005}, volume = {204}, number = {2-3}, pages = {371--384}, url = {://WOS:000226354300017 http://ac.els-cdn.com/S0378112704006875/1-s2.0-S0378112704006875-main.pdf?_tid=34117b6a-03f2-11e2-b0a8-00000aacb35d&acdnat=1348235136_6349a7b6918cc2201b2aa77635db6038}, doi = {https://doi.org/10.1016/j.foreco.2004.09.011} } |
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Barbosa, R. and Fearnside, P. | Erosão do solo na Amazônia: Estudo de caso na região do Apiaú, Roraima, Brasil. [BibTeX] |
2000 | Acta Amazônica Vol. 30, pp. 601-613 |
article | |
BibTeX:
@article{barbosa_erosao_2000, author = {Barbosa, R.I. and Fearnside, P.M.}, title = {Erosão do solo na Amazônia: Estudo de caso na região do Apiaú, Roraima, Brasil.}, journal = {Acta Amazônica}, year = {2000}, volume = {30}, pages = {601--613} } |
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Barbosa, P.M., Melack, J.M., Amaral, J.H.F., MacIntyre, S., Kasper, D., Cortés, A., Farjalla, V.F. and Forsberg, B.R. | Dissolved methane concentrations and fluxes to the atmosphere from a tropical floodplain lake | 2020 | Biogeochemistry Vol. 148(2), pp. 129-151 |
article | DOI URL |
Abstract: Large uncertainties in estimates of methane (CH4) emissions from tropical inland waters reflect the paucity of information at appropriate temporal and spatial scales. CH4 concentrations, diffusive and ebullitive fluxes, and environmental parameters in contrasting aquatic habitats of Lake Janauacá, an Amazon floodplain lake, measured for two years revealed patterns in temporal and spatial variability related to different aquatic habitats and environmental conditions. CH4 concentrations ranged from below detection to 96 µM, CH4 diffusive fluxes from below detection to 2342 µmol m−2 h−1, and CH4 ebullitive fluxes from 0 to 190 mmol m−2 d−1. Vegetated aquatic habitats had higher surface CH4 concentrations than open water habitats, and no significant differences in diffusive CH4 fluxes, likely due to higher k values measured in open water habitats. CH4 emissions were enhanced after a prolonged low water period, when the exposed sediments were colonized by herbaceous plants that decomposed after water levels rose, possibly fueling CH4 production. Statistical models indicated the importance of variables related to CH4 production (temperature, dissolved organic carbon) and consumption (dissolved nitrogen, oxygenated water column), as well as maximum depth, in controlling surface water CH4 concentrations. | |||||
BibTeX:
@article{barbosa_dissolved_2020, author = {Barbosa, Pedro M. and Melack, John M. and Amaral, João H. F. and MacIntyre, Sally and Kasper, Daniele and Cortés, Alicia and Farjalla, Vinicius F. and Forsberg, Bruce R.}, title = {Dissolved methane concentrations and fluxes to the atmosphere from a tropical floodplain lake}, journal = {Biogeochemistry}, year = {2020}, volume = {148}, number = {2}, pages = {129--151}, url = {https://doi.org/10.1007/s10533-020-00650-1}, doi = {https://doi.org/10.1007/s10533-020-00650-1} } |
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Barbosa, P.M., Melack, J.M., Amaral, J.H.F., Linkhorst, A. and Forsberg, B.R. | Large Seasonal and Habitat Differences in Methane Ebullition on the Amazon Floodplain | 2021 | Journal of Geophysical Research: Biogeosciences Vol. 126(7), pp. e2020JG005911 |
article | DOI URL |
Abstract: Abstract Tropical floodplains are an important source of methane (CH4) to the atmosphere, and ebullitive fluxes are likely to be important. We report direct measurements of CH4 ebullition in common habitats on the Amazon floodplain over two years based on floating chambers that allowed detection of bubbles, and submerged bubble traps. Ebullition was highly variable in space and time. Of the 840 floating chamber measurements (equivalent to 8,690 min of 10-min deployments), 22% captured bubbles. Ebullitive CH4 fluxes, measured using bubble traps deployed for a total of approximately 230 days, ranged from 0 to 109 mmol CH4 m−2 d−1, with a mean of 4.4 mmol CH4 m−2 d−1. During falling water, a hydroacoustic echosounder detected bubbles in 24% of the 70-m segments over 34 km. Ebullitive flux increased as the water level fell faster during falling water periods. In flooded forests, highest ebullitive fluxes occurred during falling water, while in open water and herbaceous plant habitats, higher ebullitive fluxes were measured during low water periods. The contribution of diffusive plus ebullitive CH4 flux represented by ebullition varied from 1% (high and rising water in open water of the lake) to 93% (falling water in flooded forests) based on bubble traps. Combining ebullitive and diffusive fluxes among habitats in relation to variations in water depth and areal coverage of aquatic habitats provides the basis for improved floodplain-wide estimates of CH4 evasion. | |||||
BibTeX:
@article{barbosa_large_2021, author = {Barbosa, Pedro M. and Melack, John M. and Amaral, João H. F. and Linkhorst, Annika and Forsberg, Bruce R.}, title = {Large Seasonal and Habitat Differences in Methane Ebullition on the Amazon Floodplain}, journal = {Journal of Geophysical Research: Biogeosciences}, year = {2021}, volume = {126}, number = {7}, pages = {e2020JG005911}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JG005911}, doi = {https://doi.org/10.1029/2020JG005911} } |
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Barbosa, P.M., Melack, J., Amaral, J., Farjalla, V., Scofield, V. and Forsberg, B. | Diffusive methane fluxes from Negro, Solimões and Madeira rivers and fringing lakes of the Amazon Basin [BibTeX] |
2016 | Limnology and Oceanography Vol. 61, pp. S221-S237 |
article | DOI |
BibTeX:
@article{barbosa_diffusive_2016, author = {Barbosa, P. M. and Melack, J.M. and Amaral, J.H.F. and Farjalla, V. and Scofield, V. and Forsberg, B.R.}, title = {Diffusive methane fluxes from Negro, Solimões and Madeira rivers and fringing lakes of the Amazon Basin}, journal = {Limnology and Oceanography}, year = {2016}, volume = {61}, pages = {S221--S237}, doi = {https://doi.org/10.1002/lno.10358} } |
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Barbosa, P.M., Farjalla, V.F., Melack, J.M., Amaral, J.H.F., Silva, J.S.d. and Forsberg, B.R. | High rates of methane oxidation in an Amazon floodplain lake [BibTeX] |
2018 | Biogeochemistry Vol. 137(3), pp. 351-365 |
article | |
BibTeX:
@article{barbosa_high_2018, author = {Barbosa, Pedro M. and Farjalla, Vinicius F. and Melack, John M. and Amaral, João Henrique F. and Silva, Jonismar S. da and Forsberg, Bruce R.}, title = {High rates of methane oxidation in an Amazon floodplain lake}, journal = {Biogeochemistry}, year = {2018}, volume = {137}, number = {3}, pages = {351--365} } |
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Barbosa, H.M.J., Barja, B., Pauliquevis, T., Gouveia, D.A., Artaxo, P., Cirino, G.G., Santos, R.M.N. and Oliveira, A.B. | A permanent Raman lidar station in the Amazon: description, characterization, and first results [BibTeX] |
2014 | Atmos. Meas. Tech. Vol. 7(6), pp. 1745-1762 |
article | DOI URL |
BibTeX:
@article{barbosa_permanent_2014, author = {Barbosa, H. M. J. and Barja, B. and Pauliquevis, T. and Gouveia, D. A. and Artaxo, P. and Cirino, G. G. and Santos, R. M. N. and Oliveira, A. B.}, title = {A permanent Raman lidar station in the Amazon: description, characterization, and first results}, journal = {Atmos. Meas. Tech.}, year = {2014}, volume = {7}, number = {6}, pages = {1745--1762}, url = {https://amt.copernicus.org/articles/7/1745/2014/}, doi = {https://doi.org/10.5194/amt-7-1745-2014} } |
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Barbosa, C.G.G., Taylor, P.E., Sá, M.O., Teixeira, P.R., Souza, R.A.F., Albrecht, R.I., Barbosa, H.M.J., Sebben, B., Manzi, A.O., Araújo, A.C., Prass, M., Pöhlker, C., Weber, B., Andreae, M.O. and Godoi, R.H.M. | Identification and quantification of giant bioaerosol particles over the Amazon rainforest | 2022 | Climate and Atmospheric Science Vol. 5(1), pp. 73 |
article | DOI URL |
Abstract: Eukarya dominate the coarse primary biological aerosol (PBA) above the Amazon rainforest canopy, but their vertical profile and seasonality is currently unknown. In this study, the stratification of coarse and giant PBA textgreater5 µm were analyzed from the canopy to 300 m height at the Amazon Tall Tower Observatory in Brazil during the wet and dry seasons. We show that textgreater2/3 of the coarse PBA were canopy debris, fungal spores commonly found on decaying matter were second most abundant (ranging from 15 to 41%), followed by pollens (up to 5%). The atmospheric roughness layer right above the canopy had the greatest giant PBA abundance. Measurements over 5 years showed an increased abundance of PBA during a low-rainfall period. Giant particles, such as pollen, are reduced at 300 m, suggesting their limited dispersal. These results give insights into the giant PBA emissions of this tropical rainforest, and present a major step in understanding the type of emitted particles and their vertical distribution. | |||||
BibTeX:
@article{barbosa_identification_2022, author = {Barbosa, Cybelli G. G. and Taylor, Philip E. and Sá, Marta O. and Teixeira, Paulo R. and Souza, Rodrigo A. F. and Albrecht, Rachel I. and Barbosa, Henrique M. J. and Sebben, Bruna and Manzi, Antônio O. and Araújo, Alessandro C. and Prass, Maria and Pöhlker, Christopher and Weber, Bettina and Andreae, Meinrat O. and Godoi, Ricardo H. M.}, title = {Identification and quantification of giant bioaerosol particles over the Amazon rainforest}, journal = {Climate and Atmospheric Science}, year = {2022}, volume = {5}, number = {1}, pages = {73}, url = {https://doi.org/10.1038/s41612-022-00294-y}, doi = {https://doi.org/10.1038/s41612-022-00294-y} } |
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Barbosa, C., Novo, E., Melack, J., Gastil-Buhl, M. and Pereira Filho, W. | Geospatial analysis of spatiotemporal patterns of pH, total suspended sediment and chlorophyll-a on the Amazon floodplain | 2010 | Limnology Vol. 11(2), pp. 155-166 |
article | DOI URL |
Abstract: We applied spatial data analysis and geostatistical procedures to pH, total suspended sediment and chlorophyll-a concentration data gathered on an Amazon floodplain lake. Variographic analysis and ordinary kriging interpolation were used to identify and describe spatiotemporal patterns of variability in these parameters, which are relevant to understand the dynamics of water circulation on the floodplain lake. In spite of the complexity of the processes underlying the spatiotemporal patterns, this approach demonstrated that the heterogeneity in the seasonal water composition is forced not only by the Amazon River flood pulse, but also by the lake bottom topography and the wind intensity. | |||||
BibTeX:
@article{barbosa_geospatial_2010, author = {Barbosa, C.C.F. and Novo, E.M.L.M. and Melack, J.M. and Gastil-Buhl, M. and Pereira Filho, W.}, title = {Geospatial analysis of spatiotemporal patterns of pH, total suspended sediment and chlorophyll-a on the Amazon floodplain}, journal = {Limnology}, year = {2010}, volume = {11}, number = {2}, pages = {155--166}, url = {://000278932000007 http://www.springerlink.com/content/h6412v3887v61t16/fulltext.pdf}, doi = {https://doi.org/10.1007/s10201-009-0305-5} } |
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Barbino, G.C., Antonucci, B., Ventura, D.J.S. and Andrade, N.L.R. | Sensoriamento Remoto aplicado ao Índice de Área Foliar e fração da radiação fotossinteticamente ativa em áreas de floresta e pastagem na Amazônia Ocidental. [BibTeX] |
2021 | Revista Brasileira de Meio Ambiente Vol. 9(2), pp. 76-90 |
article | |
BibTeX:
@article{barbino_sensoriamento_2021, author = {Barbino, G. C. and Antonucci, B. and Ventura, D. J. S. and Andrade, N. L. R.}, title = {Sensoriamento Remoto aplicado ao Índice de Área Foliar e fração da radiação fotossinteticamente ativa em áreas de floresta e pastagem na Amazônia Ocidental.}, journal = {Revista Brasileira de Meio Ambiente}, year = {2021}, volume = {9}, number = {2}, pages = {76--90} } |
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Barbino, G., Andrade, N., Webler, A., Sanches, L., Aguiar, R. and Antonucci, B. | Índice de área foliar e sua relação com o microclima em floresta e pastagem na Amazônia Ocidental. [BibTeX] |
2023 | Revista Brasileira de Climatologia Vol. 32 |
article | |
BibTeX:
@article{barbino_indice_2023, author = {Barbino, G.C. and Andrade, N.L.R.; and Webler, A.D.; and Sanches, L.; and Aguiar, R.G.; and Antonucci, B.}, title = {Índice de área foliar e sua relação com o microclima em floresta e pastagem na Amazônia Ocidental.}, journal = {Revista Brasileira de Climatologia}, year = {2023}, volume = {32} } |
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Barbieri, A.F., Sawyer, D.O. and Soares, B.S. | Population and land use effects on malaria prevalence in the southern Brazilian Amazon | 2005 | Human Ecology Vol. 33(6), pp. 847-874 |
article | DOI URL |
Abstract: Malaria prevalence has been one of the most dramatic outcomes of the occupation of the Brazilian Amazon as exemplified by Northern Mato Grosso, one of the areas of highest malaria prevalence in the Americas in the early 1990s. This paper associates the dynamicsof high malaria prevalence in Northern Mato Grosso with three land uses-small-scalegold mining (garimpos), agricultural colonization/cattle ranching (rural), and urban activities-and their related population characteristics, which constitute riskprofiles. Furthermore, spatial proximity and population mobility between (a) garimpos and new rural settlements and (b) older rural settlements or urban areas are key factors explaining malaria diffusion throughout the region. The paper identifies and characterizes populations at high malaria risk and the effects of land use types on malaria diffusion, providing policymakers with information for regional and local policies to control malaria and minimize its effects on Amazonian populations. | |||||
BibTeX:
@article{barbieri_population_2005, author = {Barbieri, A. F. and Sawyer, D. O. and Soares, B. S.}, title = {Population and land use effects on malaria prevalence in the southern Brazilian Amazon}, journal = {Human Ecology}, year = {2005}, volume = {33}, number = {6}, pages = {847--874}, url = {://WOS:000234022800004 http://www.springerlink.com/content/p12557331t4365n2/fulltext.pdf}, doi = {https://doi.org/10.1007/s10745-005-8213-8} } |
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Barbieri, A.F. and Carr, D.L. | Gender-specific out-migration, deforestation and urbanization in the Ecuadorian Amazon | 2005 | Global and Planetary Change Vol. 47(2-4), pp. 99-110 |
article | DOI URL |
Abstract: The Ecuadorian Amazon, one of the richest reserves of biodiversity in the world, has faced one of the highest rates of deforestation of any Amazonian nation. Most of this forest elimination has been caused by agricultural colonization that followed the discovery of oil fields in 1967. Since the 1990s, an increasing process of urbanization has also engendered new patterns of population mobility within the Amazon, along with traditional ways by which rural settlers make their living. However, while very significant in its effects on deforestation, urbanization and regional development, population mobility within the Amazon has hardly been studied at all, as well as the distinct migration patterns between men and women. This paper uses a longitudinal dataset of 250 farm households in the Northern Ecuadorian Amazon to understand differentials between men and women migrants to urban and rural destinations and between men and women non-migrants. First, we use hazard analysis based on the Kaplan-Meier (KM) estimator to obtain the cumulative probability that an individual living in the study area in 1990 or at time t, will out-migrated at some time, t+n, before 1999. Results indicate that out-migration to other rural areas in the Amazon, especially pristine areas is considerably greater than out-migration to the growing, but still incipient, Amazonian urban areas. Furthermore, men are more likely to out-migrate to rural areas than women, while the reverse occurs for urban areas. Difference-of-means tests were employed to examine potential factors accounting for differentials between male and female out-migration to urban and rural areas. Among the key results, relative to men younger women are more likely to out-migrate to urban areas; more difficult access from farms to towns and roads constrains women's migration; and access to new lands in the Amazon-an important cause of further deforestation-is more associated with male out-migration. Economic factors such as engagement in on-farm work, increasing resource scarcity-measured by higher population density at the farm and reduction in farm land on forest and crops-and increase in pasture land are more associated with male out-migration to rural areas. On the other hand, increasing resource scarcity, higher population density and weaker migration networks are more associated with female out-migration to urban areas. Thus, a "vicious cycle" is created: Pressure over land leads to deforestation in most or all farm forest areas and reduces the possibilities for further agricultural extensification (deforestation); out-migration, especially male out-migration, occurs to other rural or forest areas in the Amazon (with women being more likely to choose urban destinations); and, giving continuing population growth and pressures in the new settled areas, new pressures promote further out-migration to rural destinations and unabated deforestation. (c) 2004 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{barbieri_gender-specific_2005, author = {Barbieri, A. F. and Carr, D. L.}, title = {Gender-specific out-migration, deforestation and urbanization in the Ecuadorian Amazon}, journal = {Global and Planetary Change}, year = {2005}, volume = {47}, number = {2-4}, pages = {99--110}, note = {Edition: 2005/07/01}, url = {://WOS:000231753100004 http://ac.els-cdn.com/S0921818104001894/1-s2.0-S0921818104001894-main.pdf?_tid=2bff9a2e-03f2-11e2-bb8d-00000aab0f26&acdnat=1348235123_8501802028c8c260141daf0c077ec44a}, doi = {https://doi.org/10.1016/j.gloplacha.2004.10.005} } |
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Barbieri, A.F., Bilsborrow, R.E. and Pan, W.K. | Farm household lifecycles and land use in the Ecuadorian Amazon | 2005 | Population and Environment Vol. 27(1), pp. 1-27 |
article | DOI URL |
Abstract: This paper describes trends in population, household formation, fragmentation of landholdings, and changes in land use between 1990 and 1999 in the Northern Ecuadorian Amazon (NEA)-one of the areas of highest biodiversity in the world. It also shows how changes in land use are associated with the duration (or age) of the farm settlement, which is also linked to the stage in the farm household lifecycle and household composition. The study is based upon data from two detailed household surveys, which result in a cohort of 246 farm households interviewed in 1990 and 1999 as well as 383 new farm households constituted after 1990. Distinct patterns of land use are linked with duration of settlement, independent of when settlement occurred in the region. | |||||
BibTeX:
@article{barbieri_farm_2005, author = {Barbieri, A. F. and Bilsborrow, R. E. and Pan, W. K.}, title = {Farm household lifecycles and land use in the Ecuadorian Amazon}, journal = {Population and Environment}, year = {2005}, volume = {27}, number = {1}, pages = {1--27}, url = {://WOS:000236996300001 http://www.springerlink.com/content/y648355648717464/fulltext.pdf}, doi = {https://doi.org/10.1007/s11111-005-0013-y} } |
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Barbier, N., Couteron, P., Proisy, C., Malhi, Y. and Gastellu-Etchegorry, J.-P. | The variation of apparent crown size and canopy heterogeneity across lowland Amazonian forests | 2010 | Global Ecology and Biogeography Vol. 19(1), pp. 72-84 |
article | DOI URL |
Abstract: Aim The size structure of a forest canopy is an important descriptor of the forest environment that may yield information on forest biomass and ecology. However, its variability at regional scales is poorly described or understood because of the still prohibitive cost of very high-resolution imagery as well as the lack of an appropriate methodology. We here employ a novel approach to describe and map the canopy structure of tropical forests. Location Amazonia. Methods We apply Fourier transform textural ordination (FOTO) techniques to subsamples of very high-resolution satellite imagery freely available through virtual globe software (e.g. Google Earth (R)) to determine two key structural variables: apparent mean crown size and heterogeneity in crown size. A similar approach is used with artificial forest canopy images generated by the light interaction model (discrete anisotropic radiative transfer, DART) using three-dimensional stand models. The effects of sun and viewing angles are explored on both model and real data. Results It is shown that in the case of canopies dominated by a modal size class our approach can predict mean canopy size to an accuracy of 5%. In Amazonia, we could evidence a clear macrostructure, despite considerable local variability. Apparent crown size indeed consistently increases from about 14 m in wet north-west Amazonia to more than 17 m for areas of intermediate dry season length (1-3 months) in south and east Amazonia, before decreasing again towards the ecotone with the Cerrado savanna biome. This general trend reflects the known variation of other forest physiognomic properties (height) reported for South America and Africa. Some regions show significantly greater canopy heterogeneity, a feature that may be related to substratum, perturbation rate and/or forest turnover rate. Main conclusions Our results demonstrate the feasibility and interest of large-scale assessment of rain forest canopy structure. | |||||
BibTeX:
@article{barbier_variation_2010, author = {Barbier, Nicolas and Couteron, Pierre and Proisy, Christophe and Malhi, Yadvinder and Gastellu-Etchegorry, Jean-Philippe}, title = {The variation of apparent crown size and canopy heterogeneity across lowland Amazonian forests}, journal = {Global Ecology and Biogeography}, year = {2010}, volume = {19}, number = {1}, pages = {72--84}, url = {://WOS:000272573200007 http://onlinelibrary.wiley.com/store/10.1111/j.1466-8238.2009.00493.x/asset/j.1466-8238.2009.00493.x.pdf?v=1&t=h6hxkeop&s=7c9ef752418e8d19a6e80615d873dc484febca6b}, doi = {https://doi.org/10.1111/j.1466-8238.2009.00493.x} } |
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Banin, S.l., Lopez-Gonzalez, G., Baker, T.r., Quesada, C.A., Chao, K.-J., Burslem, D.F.R.P., Nilus, R., Abu Salim, K., Keeling, H.C., Tan, S., Davies, S.j., Monteagudo Mendoza, A., Vásquez, R., Lloyd, J., Neill, D.A., Pitman, N., Phillips Oliver L., L. and Lewis | Tropical forest wood production: a cross-continental comparison [BibTeX] |
2014 | Journal of Ecology Vol. 103 |
article | |
BibTeX:
@article{banin_tropical_2014, author = {Banin, Simon l. ; Lopez-Gonzalez, Gabriela ; Baker, Timothy r. ;Quesada, Carlos A. ; Chao, Kuo-Jung ; Burslem, David F. R. P. ; Nilus, Reuben ; Abu Salim, Kamariah ; Keeling, Helen C. ; Tan, Sylvester ; Davies, Stuart j. ; Monteagudo Mendoza, Abel ; Vásquez, Rodolfo ; Lloyd, Jon ; Neill, David A. ; Pitman, Nigel ; Phillips, Oliver L., Lindsay ; Lewis}, title = {Tropical forest wood production: a cross-continental comparison}, journal = {Journal of Ecology}, year = {2014}, volume = {103} } |
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Ballester, M.V.R., Victoria, D.D., Krusche, A.V., Coburn, R., Victoria, R.L., Richey, J.E., Logsdon, M.G., Mayorga, E. and Matricardi, E. | A remote sensing/GIS-based physical template to understand the biogeochemistry of the Ji-Parana river basin (Western Amazonia) | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 429-445 |
article | DOI URL |
Abstract: Amazonia is one of the most important ecosystems of the planet, containing the largest extent of contiguous tropical rain forest on earth, over 5 million square kilometers. While most of the region remains forested, rapid development has led, over the past two decades, to the destruction of over 589,000 km(2) of forests in Brazil alone. Forest clearing can alter the transport of sediments, organic matter and associated nutrients to the rivers. In this article, we present the results of an integrated analysis of the landscape characteristics, including soil properties, river network, topography, and land use/cover of a tropical meso-scale river. This physical template was developed as a comprehensive tool, based on Remote Sensing and GIS, to support the understanding of the biogeochemistry of surface waters of the Ji-Parana river basin, State of Rondonia, Western Amazonia. Our primary objective was to demonstrate how this tool can help the understanding of complex environmental questions, such as the effects of land-use changes in the biogeochemistry of riverine systems. River sites and basin characteristics were calculated using the data sets compiled as layers in Arc-Info GIS. A land-use/cover map for 1999 was produced from a digital classification of Landsat 7-ETM+ images. To test the effects of the landscape characteristics on river water chemistry, we performed a multiple linear regression analysis. Average slope, river network density, effective cation exchange capacity (ECEC), and proportion of pasture were treated as independent variables. River water electrical conductivity (EC) and Na+, Ca2+, Mg2+, K+, Cl- and PO43- concentrations were the dependent variables. Spatially, higher values of all ions were associated with areas dominated by pasture, with the highest concentrations found in the central part of the basin, where pasture areas are at a maximum. As the river enters the lower reaches, forests dominate the landscape, and the concentrations drop. The percentage of the basin area covered by pasture was consistently the best predictor of EC (r(2) = 0.872), PO43- (r(2) = 0.794), Na+ (r(2) =0.754), Cl- (r(2) = 0.692) and K+ (r(2) = 0.626). For Ca2+, both ECEC (r(2) = 0.538) and pasture (r(2) = 0.502) explained most of the observed variability. The same pattern was found for Mg2+ (r(2) = 0.498 and 0.502, respectively). (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{ballester_remote_2003, author = {Ballester, M. V. R. and Victoria, D. D. and Krusche, A. V. and Coburn, R. and Victoria, R. L. and Richey, J. E. and Logsdon, M. G. and Mayorga, E. and Matricardi, E.}, title = {A remote sensing/GIS-based physical template to understand the biogeochemistry of the Ji-Parana river basin (Western Amazonia)}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {429--445}, url = {://WOS:000186827400004 http://ac.els-cdn.com/S0034425703002037/1-s2.0-S0034425703002037-main.pdf?_tid=2444abc6-03f2-11e2-b814-00000aacb362&acdnat=1348235110_01a394cd52fc99a8cc7be2cc194e6689}, doi = {https://doi.org/10.1016/j.rse.2002.10.001} } |
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Ballester, M.V.R. and dos Santos, J.E. | Biogenic gases in tropical floodplain river | 2001 | Brazilian Archives of Biology and Technology Vol. 44(2), pp. 141-147 |
article | URL |
Abstract: Analysis of the distribution of biogenic gases in the floodplain of the Mogi-Guacu River (Sao Paulo, Brazil) enabled the establishment of a "redox hierarchy", in which the main channel was the most oxidizing environment, followed by Diogo Lake, with Infernao Lake having the most reducing conditions of the subsystems evaluated. Diogo Lake exported about 853.4 g C.m(-2) year(-1), of which, 14.6% was generated from methanogenesis and 36.7% by aerobic respiration. For Infernao Lake, these values were 2016 g C.m(-2) year(-1), 1.8% and 41.5%, respectively. Carbon export by these systems was predominantly in the form of CO2, which was responsible for the release of 728.78 g C.m(-2) year(-1) at Diogo Lake and 1979.72 g C.m(-2). year(-1) at Infernao Lake. Such patterns may result from the nature of the hydrological conditions, the action of the hydroperiod, and morphological characteristics of the environment. | |||||
BibTeX:
@article{ballester_biogenic_2001, author = {Ballester, M. V. R. and dos Santos, J. E.}, title = {Biogenic gases in tropical floodplain river}, journal = {Brazilian Archives of Biology and Technology}, year = {2001}, volume = {44}, number = {2}, pages = {141--147}, url = {://WOS:000172276400006} } |
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Balch, J.K., Nepstad, D.C., Curran, L.M., Brando, P.M., Portela, O., Guilherme, P., Reuning-Scherer, J.D. and de Carvalho Jr., O. | Size, species, and fire behavior predict tree and liana mortality from experimental burns in the Brazilian Amazon | 2011 | Forest Ecology and Management Vol. 261(1), pp. 68-77 |
article | DOI URL |
Abstract: Anthropogenic understory fires have affected large areas of tropical forest in recent decades, particularly during severe droughts. Yet, the mechanisms that control fire-induced mortality of tropical trees and lianas remain ambiguous due to the challenges associated with documenting mortality given variation in fire behavior and forest heterogeneity. In a seasonally dry Amazon forest, we conducted a burn experiment to quantify how increasing understory fires alter patterns of stem mortality. From 2004 to 2007, tree and liana mortality was measured in adjacent 50-ha plots that were intact (B0 - control), burned once (B1), and burned annually for 3 years (B3). After 3 years, cumulative tree and liana mortality (textgreater= 1 cm dbh) in the B1 (5.8% yr(-1)) and B3 (7.0% yr(-1)) plots significantly exceeded mortality in the control (3.2% yr(-1)). However, these fire-induced mortality rates are substantially lower than those reported from more humid Amazonian forests. Small stems were highly vulnerable to fire-induced death, contrasting with drought-induced mortality (measured in other studies) that increases with tree size. For example, one low-intensity burn killed textgreater50% of stems textless10 cm within a year. Independent of stem size, species-specific mortality rates varied substantially from 0% to 17% yr(-1) in the control, 0% to 26% yr(-1) in B1, and 1% to 23% yr(-1) in B3, with several species displaying high variation in their vulnerability to fire-induced mortality. Protium guianense (Burseraceae) exhibited the highest fire-induced mortality rates in B1 and B3, which were 10- and 9-fold greater than the baseline rate. In contrast, Aspidosperma excelsum (Apocynaceae), appeared relatively unaffected by fire (0.3% to 1.0% mortality yr(-1) across plots), which may be explained by fenestration that protects the inner concave trunk portions from fire. For stems textgreater= 10 cm, both char height (approximating fire intensity) and number of successive burns were significant predictors of fire-induced mortality, whereas only the number of consecutive annual burns was a strong predictor for stems textless10cm. Three years after the initial burn, 62+/-26 Mg ha(-1) (s.e.) of live biomass, predominantly stems textless30cm, was transferred to the dead biomass pool, compared with 8+/-3 Mg ha(-1) in the control. This biomass loss from fire represents similar to 30% of this forest's aboveground live biomass (192 (+/-3) Mg ha(-1): textgreater1 cm DBH). Although forest transition to savanna has been predicted based on future climate scenarios, our results indicate that wildfires from agricultural expansion pose a more immediate threat to the current carbon stocks in Amazonian forests. (C) 2010 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{balch_size_2011, author = {Balch, Jennifer K. and Nepstad, Daniel C. and Curran, Lisa M. and Brando, Paulo M. and Portela, Osvaldo and Guilherme, Paulo and Reuning-Scherer, Jonathan D. and de Carvalho, Jr., Oswaldo}, title = {Size, species, and fire behavior predict tree and liana mortality from experimental burns in the Brazilian Amazon}, journal = {Forest Ecology and Management}, year = {2011}, volume = {261}, number = {1}, pages = {68--77}, url = {://WOS:000285132000008 http://ac.els-cdn.com/S037811271000561X/1-s2.0-S037811271000561X-main.pdf?_tid=2f8b1a56-03f2-11e2-b4a6-00000aacb362&acdnat=1348235128_e4fde46e13c2a590d9485d6d60145648}, doi = {https://doi.org/10.1016/j.foreco.2010.09.029} } |
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Balch, J., Nepstad, D., Brando, P., Curran, L., Portela, O., de Carvalho, O.J. and Lefebvre, P. | Negative fire feedback in a transitional forest of southeastern Amazonia | 2008 | Global Change Biology Vol. 14(10), pp. 2276-2287 |
article | DOI URL |
Abstract: Anthropogenic understory fires affect large areas of tropical forest, particularly during severe droughts. Yet, the mechanisms that control tropical forests' susceptibility to fire remain ambiguous. We tested the widely accepted hypothesis that Amazon forest fires increase susceptibility to further burning by conducting a 150 ha fire experiment in a closed-canopy forest near the southeastern Amazon forest-savanna boundary. Forest flammability and its possible determinants were measured in adjacent 50 ha forest plots that were burned annually for 3 consecutive years (B3), once (B1), and not at all (B0). Contrary to expectation, an annual burning regime led to a decline in forest flammability during the third burn. Microclimate conditions were more favorable compared with the first burn (i.e. vapor pressure deficit increased and litter moisture decreased), yet flame heights declined and burned area halved. A slight decline in fine fuels after the second burn appears to have limited fire spread and intensity. Supporting this conclusion, fire spread rates doubled and burned area increased fivefold in B3 subplots that received fine fuel additions. Slow replacement of surface fine fuels in this forest may be explained by (i) low leaf litter production (4.3 Mg ha(-1) yr(-1)), half that of other Amazon forests; and (ii) low fire-induced tree and liana mortality (5.5 +/- 0.5% yr(-1), SE, in B3), the lowest measured in closed-canopy Amazonian forests. In this transitional forest, where severe seasonal drought removed moisture constraints on fire propagation, a lack of fine fuels inhibited the intensity and spread of recurrent fire in a negative feedback. This reduction in flammability, however, may be short-lived if delayed tree mortality or treefall increases surface fuels in future years. This study highlights that understanding fuel input rate and timing relative to fire frequency is fundamental to predicting transitional forest flammability - which has important implications for carbon emissions and potential replacement by scrub vegetation. | |||||
BibTeX:
@article{balch_negative_2008, author = {Balch, J.K. and Nepstad, D.C. and Brando, P.M. and Curran, L.M. and Portela, O. and de Carvalho, O. Jr. and Lefebvre, P.}, title = {Negative fire feedback in a transitional forest of southeastern Amazonia}, journal = {Global Change Biology}, year = {2008}, volume = {14}, number = {10}, pages = {2276--2287}, url = {://WOS:000259360500005 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2008.01655.x/asset/j.1365-2486.2008.01655.x.pdf?v=1&t=h6hxk92j&s=6084030f441a10c6b561a00e26099289266f57e4}, doi = {https://doi.org/10.1111/j.1365-2486.2008.01655.x} } |
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Baker, T.R., Phillips, O.L., Malhi, Y., Almeida, S., Arroyo, L., Di Fiore, A., Erwin, T., Killeen, T.J., Laurance, S.G., Laurance, W.F., Lewis, S.L., Lloyd, J., Monteagudo, A., Neill, D.A., Patino, S., Pitman, N.C.A., Silva, J.N.M. and Martinez, R.V. | Variation in wood density determines spatial patterns in Amazonian forest biomass | 2004 | Global Change Biology Vol. 10(5), pp. 545-562 |
article | DOI URL |
Abstract: Uncertainty in biomass estimates is one of the greatest limitations to models of carbon flux in tropical forests. Previous comparisons of field-based estimates of the aboveground biomass (AGB) of trees greater than 10 cm diameter within Amazonia have been limited by the paucity of data for western Amazon forests, and the use of site-specific methods to estimate biomass from inventory data. In addition, the role of regional variation in stand-level wood specific gravity has not previously been considered. Using data from 56 mature forest plots across Amazonia, we consider the relative roles of species composition (wood specific gravity) and forest structure (basal area) in determining variation in AGB. Mean stand-level wood specific gravity, on a per stem basis, is 15.8% higher in forests in central and eastern, compared with northwestern Amazonia. This pattern is due to the higher diversity and abundance of taxa with high specific gravity values in central and eastern Amazonia, and the greater diversity and abundance of taxa with low specific gravity values in western Amazonia. For two estimates of AGB derived using different allometric equations, basal area explains 51.7% and 63.4%, and stand-level specific gravity 45.4% and 29.7%, of the total variation in AGB. The variation in specific gravity is important because it determines the regional scale, spatial pattern of AGB. When weighting by specific gravity is included, central and eastern Amazon forests have significantly higher AGB than stands in northwest or southwest Amazonia. The regional-scale pattern of species composition therefore defines a broad gradient of AGB across Amazonia. | |||||
BibTeX:
@article{baker_variation_2004, author = {Baker, T. R. and Phillips, O. L. and Malhi, Y. and Almeida, S. and Arroyo, L. and Di Fiore, A. and Erwin, T. and Killeen, T. J. and Laurance, S. G. and Laurance, W. F. and Lewis, S. L. and Lloyd, J. and Monteagudo, A. and Neill, D. A. and Patino, S. and Pitman, N. C. A. and Silva, J. N. M. and Martinez, R. V.}, title = {Variation in wood density determines spatial patterns in Amazonian forest biomass}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {545--562}, url = {://WOS:000221421600003 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2486.2004.00751.x/asset/j.1365-2486.2004.00751.x.pdf?v=1&t=h6hxk1zk&s=ecc68aa384bcafc60e291d366a131f03c2c00363}, doi = {https://doi.org/10.1111/j.1365-2486.2004.00751.x} } |
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Baker, T.R., Phillips, O.L., Malhi, Y., Almeida, S., Arroyo, L., Di Fiore, A., Erwin, T., Higuchi, N., Killeen, T.J., Laurance, S.G., Laurance, W.F., Lewis, S.L., Monteagudo, A., Neill, D.A., Vargas, P.N., Pitman, N.C.A., Silva, J.N.M. and Martinez, R.V. | Increasing biomass in Amazonian forest plots | 2004 | Philosophical Transactions of the Royal Society of London Series B-Biological Sciences Vol. 359(1443), pp. 353-365 |
article | DOI URL |
Abstract: A previous study by Phillips et al. of changes in the biomass of permanent sample plots in Amazonian forests was used to infer the presence of a regional carbon sink. However, these results generated a vigorous debate about sampling and methodological issues. Therefore we present a new analysis of biomass change in old-growth Amazonian forest plots using updated inventory data. We find that across 59 sites, the above-ground dry biomass in trees that are more than 10 cm in diameter (AGB) has increased since plot establishment by 1.22 +/- 0.43 Mg per hectare per year (ha(-1) yr(-1), where 1 ha = 10(4) m(2)), or 0.98 +/- 0.38 Mg ha(-1) yr(-1) if individual plot values are weighted by the number of hectare years of monitoring. This significant increase is neither confounded by spatial or temporal variation in wood specific gravity, nor dependent on the allometric equation used to estimate AGB. The conclusion is also robust to uncertainty about diameter measurements for problematic trees: for 34 plots in western Amazon forests a significant increase in AGB is found even with a conservative assumption of zero growth for all trees where diameter measurements were made using optical methods and/or growth rates needed to be estimated following fieldwork. Overall, our results suggest a slightly greater rate of net stand-level change than was reported by Phillips et al. Considering the spatial and temporal scale of sampling and associated studies showing increases in forest growth and stem turnover, the results presented here suggest that the total biomass of these plots has on average increased and that there has been a regional-scale carbon sink in old-growth Amazonian forests during the previous two decades. | |||||
BibTeX:
@article{baker_increasing_2004, author = {Baker, T. R. and Phillips, O. L. and Malhi, Y. and Almeida, S. and Arroyo, L. and Di Fiore, A. and Erwin, T. and Higuchi, N. and Killeen, T. J. and Laurance, S. G. and Laurance, W. F. and Lewis, S. L. and Monteagudo, A. and Neill, D. A. and Vargas, P. N. and Pitman, N. C. A. and Silva, J. N. M. and Martinez, R. V.}, title = {Increasing biomass in Amazonian forest plots}, journal = {Philosophical Transactions of the Royal Society of London Series B-Biological Sciences}, year = {2004}, volume = {359}, number = {1443}, pages = {353--365}, note = {Edition: 2004/06/24}, url = {://WOS:000220545100005 http://rstb.royalsocietypublishing.org/content/359/1443/353.full.pdf}, doi = {https://doi.org/10.1098/rstb.2003.1422} } |
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Baker, T.R., Phillips, O.L., Laurance, W.F., Pitman, N.C.A., Almeida, S., Arroyo, L., DiFiore, A., Erwin, T., Higuchi, N., Killeen, T.J., Laurance, S.G., Nascimento, H., Monteagudo, A., Neill, D.A., Silva, J.N.M., Malhi, Y., Gonzalez, G.L., Peacock, J., Quesada, C.A., Lewis, S.L. and Lloyd, J. | Do species traits determine patterns of wood production in Amazonian forests? | 2009 | Biogeosciences Vol. 6(2), pp. 297-307 |
article | URL |
Abstract: Understanding the relationships between plant traits and ecosystem properties at large spatial scales is important for predicting how compositional change will affect carbon cycling in tropical forests. In this study, we examine the relationships between species wood density, maximum height and above-ground, coarse wood production of trees textgreater= 10 cm diameter (CWP) for 60 Amazonian forest plots. Average species maximum height and wood density are lower in Western than Eastern Amazonia and are negatively correlated with CWP. To test the hypothesis that variation in these traits causes the variation in CWP, we generate plot-level estimates of CWP by resampling the full distribution of tree biomass growth rates whilst maintaining the appropriate tree-diameter and functional-trait distributions for each plot. These estimates are then compared with the observed values. Overall, the estimates do not predict the observed, regional-scale pattern of CWP, suggesting that the variation in communitylevel trait values does not determine variation in coarse wood productivity in Amazonian forests. Instead, the regional gradient in CWP is caused by higher biomass growth rates across all tree types in Western Amazonia. Therefore, the regional gradient in CWP is driven primarily by environmental factors, rather than the particular functional composition of each stand. These results contrast with previous findings for forest biomass, where variation in wood density, associated with variation in species composition, is an important driver of regional-scale patterns in above-ground biomass. Therefore, in tropical forests, above-ground wood productivity may be less sensitive than biomass to compositional change that alters community-level averages of these plant traits. | |||||
BibTeX:
@article{baker_species_2009, author = {Baker, T. R. and Phillips, O. L. and Laurance, W. F. and Pitman, N. C. A. and Almeida, S. and Arroyo, L. and DiFiore, A. and Erwin, T. and Higuchi, N. and Killeen, T. J. and Laurance, S. G. and Nascimento, H. and Monteagudo, A. and Neill, D. A. and Silva, J. N. M. and Malhi, Y. and Gonzalez, G. Lopez and Peacock, J. and Quesada, C. A. and Lewis, S. L. and Lloyd, J.}, title = {Do species traits determine patterns of wood production in Amazonian forests?}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {2}, pages = {297--307}, url = {://WOS:000263839200014} } |
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Baker, T.R., Jones, J.P.G., Thompson, O.R.R., Roman Cuesta, R.M., del Castillo, D., Aguilar, I.C., Torres, J. and Healey, J.R. | How can ecologists help realise the potential of payments for carbon in tropical forest countries? | 2010 | Journal of Applied Ecology Vol. 47(6), pp. 1159-1165 |
article | DOI URL |
Abstract: 1. There is great interest among policy makers in the potential of carbon-based payments for ecosystem services (PES) to reduce carbon emissions from deforestation and protect forests in tropical countries. We discuss the contributions that ecologists can make to the interdisciplinary research required to inform the design of these initiatives. 2. First, we highlight the need to quantify the full range of processes that determine temporal variation in carbon stocks at a landscape-scale due to cycles of forest disturbance and recovery. Second, we discuss the importance of understanding how the impact of climate change on the carbon stocks of intact forests may affect the emissions reductions achieved by any given project: we show that this may reduce the effectiveness of one carbon-based PES project in southern Peru by 15%. We also discuss the need to assess project impacts on deforestation in the surrounding region and explore how different project designs influence the balance between the conservation of carbon and biodiversity. 3. The need to demonstrate emissions reductions or carbon storage to investors in carbon-based payment schemes provides an imperative for monitoring their effectiveness. Monitoring will be a significant cost in any PES project and, together with project set-up, on average accounts for more than 40% of project expenditure across six emerging Peruvian PES schemes. Ecologists will therefore have an important role in designing cost-effective monitoring strategies. The impetus for monitoring also provides opportunities to carry out research addressing many of the uncertainties highlighted above. 4. Synthesis and applications. By working closely with a range of carbon-based PES projects, ecologists can answer important fundamental questions related to the provision of ecosystem services and help improve the design of these schemes. The large number of projects currently being implemented provides an unprecedented opportunity to develop a proper evidence base for measuring and improving the practices that most successfully conserve tropical forest ecosystems. | |||||
BibTeX:
@article{baker_how_2010, author = {Baker, Tim R. and Jones, Julia P. G. and Thompson, Olivia R. Rendon and Roman Cuesta, Rosa Maria and del Castillo, Dennis and Aguilar, Ivis Chan and Torres, Jorge and Healey, John R.}, title = {How can ecologists help realise the potential of payments for carbon in tropical forest countries?}, journal = {Journal of Applied Ecology}, year = {2010}, volume = {47}, number = {6}, pages = {1159--1165}, url = {://WOS:000283983200001 http://onlinelibrary.wiley.com/store/10.1111/j.1365-2664.2010.01885.x/asset/j.1365-2664.2010.01885.x.pdf?v=1&t=h6hxjvmu&s=a8ab5d687d59ecf6c0bf3b6757754ce679cbfc86}, doi = {https://doi.org/10.1111/j.1365-2664.2010.01885.x} } |
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Baker, T.R., Coronado, E.N.H., Phillips, O.L., Martin, J., van der Heijden, G.M.F., Garcia, M. and Silva Espejo, J. | Low stocks of coarse woody debris in a southwest Amazonian forest | 2007 | Oecologia Vol. 152(3), pp. 495-504 |
article | DOI URL |
Abstract: The stocks and dynamics of coarse woody debris (CWD) are significant components of the carbon cycle within tropical forests. However, to date, there have been no reports of CWD stocks and fluxes from the approximately 1.3 million km(2) of lowland western Amazonian forests. Here, we present estimates of CWD stocks and annual CWD inputs from forests in southern Peru. Total stocks were low compared to other tropical forest sites, whether estimated by line-intercept sampling (24.4 +/- 5.3 Mg ha(-1)) or by complete inventories within 11 permanent plots (17.7 +/- 2.4 Mg ha(-1)). However, annual inputs, estimated from long-term data on tree mortality rates in the same plots, were similar to other studies (3.8 +/- 0.2 or 2.9 +/- 0.2 Mg ha(-1) year(-1), depending on the equation used to estimate biomass). Assuming the CWD pool is at steady state, the turnover time of coarse woody debris is low (4.7 +/- 2.6 or 6.1 +/- 2.6 years). These results indicate that these sites have not experienced a recent, large-scale disturbance event and emphasise the distinctive, rapid nature of carbon cycling in these western Amazonian forests. | |||||
BibTeX:
@article{baker_low_2007, author = {Baker, Timothy R. and Coronado, Euridice N. Honorio and Phillips, Oliver L. and Martin, Jim and van der Heijden, Geertje M. F. and Garcia, Michael and Silva Espejo, Javier}, title = {Low stocks of coarse woody debris in a southwest Amazonian forest}, journal = {Oecologia}, year = {2007}, volume = {152}, number = {3}, pages = {495--504}, note = {Edition: 2007/03/03}, url = {://WOS:000246614700010 http://www.springerlink.com/content/9347k52223v700n6/fulltext.pdf}, doi = {https://doi.org/10.1007/s00442-007-0667-5} } |
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Baker, T., Pennington, R., Magallon, S., Gloor, E. and Laurance WF Alvarez E, A.A.A.E.A.G.d.O.A.A.I.A.L.B.D.B.R.C.J.D.K.D.F.A.E.E.F.T.F.L.L.-G.G.v.d.H.G.H.N.H.E.H.I.K.T.L.S.L.C.L.S.M.Y.M.B.M.J.B.M.M.A.N.D.P.-M.M.P.N.P.A.Q.C.R.F.R.A.H.R.A.R.A.S.R.d.A.A.S.J.S.M.S.M.S.W.S.H.T.J.T.M.T.-L.A.V.R.V.I.V.E.V.V.&.P.O.A.M. | Fast demographic traits promote high diversification rates of Amazonian trees. [BibTeX] |
2014 | Ecology Letters Vol. 17(5), pp. 527-536 |
article | DOI |
BibTeX:
@article{baker_fast_2014, author = {Baker, TR. and Pennington, RT. and Magallon, S. and Gloor, E. and Laurance WF, Alvarez E, Araujo A, Arets EJMM, Aymard G, de Oliveira AA, Amaral I, Arroyo L, Bonal D, Brienen RJW, Chave J, Dexter KG, Di Fiore A, Eler E, Feldpausch TR, Ferreira L, Lopez-Gonzalez G, van der Heijden G, Higuchi N, Honorio E, Huamantupa I, Killeen TJ, Laurance S, Leaño C, Lewis SL, Malhi Y, Marimon BS, Marimon Junior BH, Monteagudo Mendoza A, Neill D, Peñuela-Mora MC, Pitman N, Prieto A, Quesada CA, Ramírez F, Ramírez Angulo H, Rudas A, Ruschel AR, Salomão RP, de Andrade AS, Silva JNM, Silveira M, Simon MF, Spironello W, Steege H, Terborgh J, Toledo M, Torres-Lezama A, Vasquez R, Vieira ICG, Vilanova E, Vos VA & Phillips OL, Alexiades M}, title = {Fast demographic traits promote high diversification rates of Amazonian trees.}, journal = {Ecology Letters}, year = {2014}, volume = {17}, number = {5}, pages = {527--536}, doi = {https://doi.org/10.1111/ele.12252} } |
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Baker, J.C.A., Garcia-Carreras, L., Gloor, M., Marsham, J.H., Buermann, W., da Rocha, H.R., Nobre, A.D., de Araujo, A.C. and Spracklen, D.V. | Evapotranspiration in the Amazon: spatial patterns, seasonality, and recent trends in observations, reanalysis, and climate models [BibTeX] |
2021 | Hydrol. Earth Syst. Sci. Vol. 25(4), pp. 2279-2300 |
article | DOI URL |
BibTeX:
@article{baker_evapotranspiration_2021, author = {Baker, J. C. A. and Garcia-Carreras, L. and Gloor, M. and Marsham, J. H. and Buermann, W. and da Rocha, H. R. and Nobre, A. D. and de Araujo, A. C. and Spracklen, D. V.}, title = {Evapotranspiration in the Amazon: spatial patterns, seasonality, and recent trends in observations, reanalysis, and climate models}, journal = {Hydrol. Earth Syst. Sci.}, year = {2021}, volume = {25}, number = {4}, pages = {2279--2300}, url = {https://hess.copernicus.org/articles/25/2279/2021/}, doi = {https://doi.org/10.5194/hess-25-2279-2021} } |
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Baker, I.T., Prihodko, L., Denning, A.S., Goulden, M., Miller, S. and da Rocha, H.R. | Seasonal drought stress in the Amazon: Reconciling models and observations | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: The Amazon Basin is crucial to global circulatory and carbon patterns due to the large areal extent and large flux magnitude. Biogeophysical models have had difficulty reproducing the annual cycle of net ecosystem exchange (NEE) of carbon in some regions of the Amazon, generally simulating uptake during the wet season and efflux during seasonal drought. In reality, the opposite occurs. Observational and modeling studies have identified several mechanisms that explain the observed annual cycle, including: (1) deep soil columns that can store large water amount, (2) the ability of deep roots to access moisture at depth when near-surface soil dries during annual drought, (3) movement of water in the soil via hydraulic redistribution, allowing for more efficient uptake of water during the wet season, and moistening of near-surface soil during the annual drought, and (4) photosynthetic response to elevated light levels as cloudiness decreases during the dry season. We incorporate these mechanisms into the third version of the Simple Biosphere model (SiB3) both singly and collectively, and confront the results with observations. For the forest to maintain function through seasonal drought, there must be sufficient water storage in the soil to sustain transpiration through the dry season in addition to the ability of the roots to access the stored water. We find that individually, none of these mechanisms by themselves produces a simulation of the annual cycle of NEE that matches the observed. When these mechanisms are combined into the model, NEE follows the general trend of the observations, showing efflux during the wet season and uptake during seasonal drought. | |||||
BibTeX:
@article{baker_seasonal_2008, author = {Baker, I. T. and Prihodko, L. and Denning, A. S. and Goulden, M. and Miller, S. and da Rocha, H. R.}, title = {Seasonal drought stress in the Amazon: Reconciling models and observations}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://WOS:000257744600001 http://www.agu.org/pubs/crossref/2008/2007JG000644.shtml}, doi = {https://doi.org/10.1029/2007jg000644} } |
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Baker, I., Harper, A., Rocha, H.d., Denning, A., Araújom, A., Bormad, L., Freitase, H., Goulden, M., Manzi, A., Miller, S., Nobre, A., Restrepo-Coupe, N., Saleska, S., Stöckli, R., von Randow, C. and Wofsy, S. | Surface ecophysiological behavior across vegetation and moisture gradients in tropical South America [BibTeX] |
2013 | Agricultural and Forest Meteorology Vol. 182-183, pp. 177-188 |
article | |
BibTeX:
@article{baker_surface_2013, author = {Baker, I.T. and Harper, A.B. and Rocha, H.R. da and Denning, A.S. and Araújom, A.C. and Bormad, L.S. and Freitase, H.C. and Goulden, M.L. and Manzi, A.O. and Miller, S.D. and Nobre, A.D. and Restrepo-Coupe, N. and Saleska, S.R. and Stöckli, R. and von Randow, C. and Wofsy, S.C.}, title = {Surface ecophysiological behavior across vegetation and moisture gradients in tropical South America}, journal = {Agricultural and Forest Meteorology}, year = {2013}, volume = {182-183}, pages = {177--188} } |
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Baccaro, I., Del Aguila, B., Schietti, J., Emilio, T., Pinto, J.L., Lima, A., Magnusson W.E., F. and Rocha | Changes in Ground-dwelling Ant Functional Diversity are Correlated with Water-Table Level in an Amazonian Terra Firme Forest [BibTeX] |
2013 | Biotropica Vol. 45 |
article | |
BibTeX:
@article{baccaro_changes_2013, author = {Baccaro, I.F.; Del Aguila, B.E.G.; Schietti, J.; Emilio, T.; Pinto, J. L.P.V.; Lima, A.P.; Magnusson, W.E., F.B.; Rocha}, title = {Changes in Ground-dwelling Ant Functional Diversity are Correlated with Water-Table Level in an Amazonian Terra Firme Forest}, journal = {Biotropica}, year = {2013}, volume = {45} } |
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Baars Thomas Engelmann, R.A.D.H.B.K.M.P.J.T.M.A.A.W.U.L.J.-H.A.J.Y.S.I.S.A.V.M.E.S.P.H.J.S.A.S.F.B.S.F.A.B.S.P.A.G.E.L.H.e.a.H.K. | An overview of the first decade of PollyNET: an emerging network of automated Raman-polarization lidars for continuous aerosol profiling [BibTeX] |
2016 | Atmospheric Chemistry and Physics Vol. 16, pp. 5111-5137 |
article | |
BibTeX:
@article{baars_overview_2016, author = {Baars, Thomas Engelmann, Ronny Althausen, Dietrich Heese, Birgit Komppula, Mika Preißler, Jana Tesche, Matthias Ansmann, Albert Wandinger, Ulla Lim, Jae-Hyun Ahn, Joon Young Stachlewska, Iwona S. Amiridis, Vassilis Marinou, Eleni Seifert, Patric Hofer, Julian Skupin, Annett Schneider, Florian Bohlmann, Stephanie Foth, Andreas Bley, Sebastian Pfüller, Anne Giannakaki, Eleni Lihavainen, Heikki, et al., Holger Kanitz}, title = {An overview of the first decade of PollyNET: an emerging network of automated Raman-polarization lidars for continuous aerosol profiling}, journal = {Atmospheric Chemistry and Physics}, year = {2016}, volume = {16}, pages = {5111--5137} } |
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Baars, D.A., R. Engelmann, B.H., D. Muller, P.A., M. Paixao, T.P. and R. Souza, H.A.A. | Aerosol profiling with lidar in the Amazon Basin during the wet and dry season [BibTeX] |
2012 | Journal of Geophysical Research-Atmospheres Vol. 117(D21201) |
article | DOI |
BibTeX:
@article{baars_aerosol_2012, author = {Baars, D. Althausen, R. Engelmann, B. Heese, D. Muller, P. Artaxo, M. Paixao, T. Pauliquevis, R. Souza, H. A. Ansmann}, title = {Aerosol profiling with lidar in the Amazon Basin during the wet and dry season}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2012}, volume = {117}, number = {D21201}, doi = {https://doi.org/10.1029/2012JD018338} } |
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Baars, H., T. Kanitz, R. Engelmann, B. Heese, M. Kompulla, A. Ansmann, U.Wandinger, J.-H. Lim, J. Y. Ahn, J. Preißler, I. Stachlewska, M. Tesche, P. Seifert, A. Skupin, A. Hänel, F. Schneider, S. Bohlmann, A. Foth, S. Bley, V. Amiridis, A. Pfüller, E. Marinou, E. Giannakaki, H. Lihavainen, Y. Viisanen, P. Achtert, P. Artaxo, T. Pauliquevis, R. Souza, R. K. Hooda, V. P. Sharma, P.G. van Zyl, J.P. Beukes, J. Sun, C. Casiccia, E. G. Rohwer, S. Pereira, F. Wagner, R. Deng and Althausen, D. | PollyNET: a global network of automated Raman-polarization lidars for continuous aerosol profiling [BibTeX] |
2015 | Atmospheric Chemistry and Physics Discussions Vol. 15, pp. 27943-28004 |
article | DOI |
BibTeX:
@article{baars_pollynet_2015, author = {Baars, H. and T. Kanitz and R. Engelmann and B. Heese and M. Kompulla and A. Ansmann and U.Wandinger and J.-H. Lim and J. Y. Ahn and J. Preißler and I. Stachlewska and M. Tesche and P. Seifert and A. Skupin and A. Hänel and F. Schneider and S. Bohlmann and A. Foth and S. Bley and V. Amiridis and A. Pfüller and E. Marinou and E. Giannakaki and H. Lihavainen and Y. Viisanen and P. Achtert and P. Artaxo and T. Pauliquevis and R. Souza and R. K. Hooda and V. P. Sharma and P.G. van Zyl and J.P. Beukes and J. Sun and C. Casiccia and E. G. Rohwer and S. Pereira and F. Wagner and R. Deng and Althausen, D.}, title = {PollyNET: a global network of automated Raman-polarization lidars for continuous aerosol profiling}, journal = {Atmospheric Chemistry and Physics Discussions}, year = {2015}, volume = {15}, pages = {27943--28004}, note = {Edition: www.atmos-chem-phys-discuss.net/15/27943/2015/.}, doi = {https://doi.org/10.5194/acpd-15-27943-2015} } |
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Baars, H., Ansmann, A., Althausen, D., Engelmann, R., Artaxo, P., Pauliquevis, T. and Souza, R. | Further evidence for significant smoke transport from Africa to Amazonia | 2011 | Geophysical Research Letters Vol. 38 |
article | DOI URL |
Abstract: Polarization-Raman-lidar observations of vertical aerosol profiles were performed 60 km north of Manaus, Brazil, in the Amazon rain forest during Amazonia's wet season from January to May 2008. Very clean background conditions with a mean AOD (532 nm) of 0.03 +/- 0.02 were frequently found. However, in about one third of all lidar measurements advection of smoke and dust aerosol from Africa were observed. The contribution of African smoke and Saharan dust particles to the total backscatter and extinction coefficient was determined by means of the measured particle depolarization ratio. A decreasing contribution of smoke particles to the total particle extinction coefficient from values around 60%-80% in January and February 2008, to values of 0%-50% in May 2008 was observed. Smoke-related extinction coefficients and optical depths up to 80 Mm(-1) and 0.15 at 532 nm, respectively, were recorded. Citation: Baars, H., A. Ansmann, D. Althausen, R. Engelmann, P. Artaxo, T. Pauliquevis, and R. Souza (2011), Further evidence for significant smoke transport from Africa to Amazonia, Geophys. Res. Lett., 38, L20802, doi:10.1029/2011GL049200. | |||||
BibTeX:
@article{baars_further_2011, author = {Baars, H. and Ansmann, A. and Althausen, D. and Engelmann, R. and Artaxo, P. and Pauliquevis, T. and Souza, R.}, title = {Further evidence for significant smoke transport from Africa to Amazonia}, journal = {Geophysical Research Letters}, year = {2011}, volume = {38}, url = {://WOS:000296157100002 http://www.agu.org/journals/gl/gl1120/2011GL049200/2011GL049200.pdf}, doi = {https://doi.org/10.1029/2011gl049200} } |
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Azevedo-Ramos, C., do Amaral, B.D., Nepstad, D., Soares Filho, B. and Nasi, R. | Integrating ecosystem management, protected areas, and mammal conservation in the Brazilian Amazon | 2006 | Ecology and Society Vol. 11(2) |
article | URL |
Abstract: The Amazon forest has been converted to a matrix of pristine and modified habitats. Landscape-scale biodiversity conservation requires an understanding of species' distributions over this matrix to guarantee both effective protection and use for present and future generations. In this study, we evaluated how much of the existing and future planned protected areas (PAs) would be contributing to the conservation of Brazilian Amazon mammals (N = 399), including threatened species (N = 51). Currently, almost 37% of Brazilian Amazon is protected and that may increase to 46% if planned PAs are implemented. In the current PA system, 22% are indigenous land and 11% are sustainable use units, e.g., production forests. Only one-fifth of the whole range of mammal species occurring in Brazilian Amazon is actually protected by Brazilian PAs. However, considering only the part of the ranges within the Brazilian Amazon, and therefore under the scope of Brazilian actions, Brazilian PAs assume an important role in the protection of 39% of mammal distribution ranges, particularly the threatened species (39%). These results suggest that an integrated network of protected areas among Amazon countries would be necessary to increase their efficiency in mammal conservation. The need for strengthening of the forest sector and good management practices in Brazil appears critical for the maintenance of large extents of forest and species conservation. Under such a scenario, the contribution of developed nations and international agencies must assume an important role for the maintenance and enlargement of the protected area network in Amazon region. | |||||
BibTeX:
@article{azevedo-ramos_integrating_2006, author = {Azevedo-Ramos, C. and do Amaral, B. D. and Nepstad, D.C. and Soares Filho, B. and Nasi, R.}, title = {Integrating ecosystem management, protected areas, and mammal conservation in the Brazilian Amazon}, journal = {Ecology and Society}, year = {2006}, volume = {11}, number = {2}, url = {://WOS:000243280800018} } |
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Avissar, R. and Werth, D. | Global hydroclimatological teleconnections resulting from tropical deforestation | 2005 | Journal of Hydrometeorology Vol. 6(2), pp. 134-145 |
article | DOI URL |
Abstract: Past studies have indicated that deforestation of the Amazon basin would result in an important rainfall decrease in that region but that this process had no significant impact on the global temperature or precipitation and had only local implications. Here it is shown that deforestation of tropical regions significantly affects precipitation at mid- and high latitudes through hydrometeorological teleconnections. In particular, it is found that the deforestation of Amazonia and Central Africa severely reduces rainfall in the lower U.S. Midwest during the spring and summer seasons and in the upper U.S. Midwest during the winter and spring, respectively, when water is crucial for agricultural productivity in these regions. Deforestation of Southeast Asia affects China and the Balkan Peninsula most significantly. On the other hand, the elimination of any of these tropical forests considerably enhances summer rainfall in the southern tip of the Arabian Peninsula. The combined effect of deforestation of these three tropical regions causes a significant decrease in winter precipitation in California and seems to generate a cumulative enhancement of precipitation during the summer in the southern tip of the Arabian Peninsula. | |||||
BibTeX:
@article{avissar_global_2005, author = {Avissar, R. and Werth, D.}, title = {Global hydroclimatological teleconnections resulting from tropical deforestation}, journal = {Journal of Hydrometeorology}, year = {2005}, volume = {6}, number = {2}, pages = {134--145}, url = {://WOS:000228975200003 http://journals.ametsoc.org/doi/pdf/10.1175/JHM406.1}, doi = {https://doi.org/10.1175/jhm406.1} } |
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Avissar, R. and Werth, D. | Comments on "The regional evapotranspiration of the Amazon'' - Reply [BibTeX] |
2004 | Journal of Hydrometeorology Vol. 5(6), pp. 1281-1281 |
article | DOI URL |
BibTeX:
@article{avissar_comments_2004, author = {Avissar, R. and Werth, D.}, title = {Comments on "The regional evapotranspiration of the Amazon'' - Reply}, journal = {Journal of Hydrometeorology}, year = {2004}, volume = {5}, number = {6}, pages = {1281--1281}, url = {://WOS:000226184000021 http://journals.ametsoc.org/doi/pdf/10.1175/JHM-394.1}, doi = {https://doi.org/10.1175/jhm-394.1} } |
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Avissar, R. and Nobre, C.A. | Preface to special issue on the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) [BibTeX] |
2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
BibTeX:
@article{avissar_preface_2002, author = {Avissar, R. and Nobre, C. A.}, title = {Preface to special issue on the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://000180466200031 http://www.agu.org/journals/jd/jd0217/2002JD002507/2002JD002507.pdf}, doi = {https://doi.org/10.1029/2002jd002507} } |
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Avissar, R., Dias, P.L.S., Dias, M. and Nobre, C. | The Large-Scale Biosphere-atmosphere Experiment in Amazonia (LBA): Insights and future research needs | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: This overview summarizes general Large-Scale Atmosphere-Biosphere Experiment in Amazonia (LBA) papers and highlights some of the insights gained from these investigations and needs for future research. It complements the overview of Silva Dias et al. [2002a], which summarizes the papers published on the joint major atmospheric mesoscale campaign in the wet season (WetAMC), which was held jointly in Rondonia with the Tropical Rainfall Measuring Mission (TRMM) validation campaign known as TRMM-LBA. It also complements the overview of Andreae et al. [2002], which summarizes the papers describing the biogeochemical cycling of carbon, water, energy, aerosols, and trace gases resulting from the European Studies on Trace Gases and Atmospheric Chemistry, known as LBA-EUSTACH Project. The 17 papers summarized under this part of the special issue are regrouped into three main categories: (1) measurements and data sets, (2) remote sensing, and (3) modeling. | |||||
BibTeX:
@article{avissar_large-scale_2002, author = {Avissar, R. and Dias, P. L. S. and Dias, Mafs and Nobre, C.}, title = {The Large-Scale Biosphere-atmosphere Experiment in Amazonia (LBA): Insights and future research needs}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200081 http://www.agu.org/journals/jd/jd0220/2002JD002704/2002JD002704.pdf}, doi = {https://doi.org/10.1029/2002jd002704} } |
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Avissar, R., da Silva, R.R. and Werth, D. | Implications of tropical deforestation for regional and global hydroclimate | 2004 | Vol. 153Ecosystems and Land Use Change, pp. 73-83 |
incollection | DOI URL |
Abstract: Land-cover heterogeneity created by deforestation of tropical forests generates atmospheric circulations that can trigger the formation of clouds and result in enhanced precipitation over the deforested region. Furthermore, the regional perturbation in atmospheric pressure generated by such massive land-cover change can excite synoptic-scale waves that propagate outside of tropical regions, resulting in significant change in the annual precipitation pattern at mid- and even high latitudes. | |||||
BibTeX:
@incollection{defries_implications_2004, author = {Avissar, R. and da Silva, R. R. and Werth, D.}, title = {Implications of tropical deforestation for regional and global hydroclimate}, booktitle = {Ecosystems and Land Use Change}, year = {2004}, volume = {153}, pages = {73--83}, url = {://WOS:000226789500006 http://www.agu.org/books/gm/v153/153GM07/153GM07.shtml}, doi = {https://doi.org/10.1029/153gm07} } |
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Aufdenkampe, A.K., Mayorga, E., Hedges, J.I., Llerena, C., Quay, P.D., Gudeman, J., Krusche, A.V. and Richey, J.E. | Organic matter in the Peruvian headwaters of the Amazon: Compositional evolution from the Andes to the lowland Amazon mainstem | 2007 | Organic Geochemistry Vol. 38(3), pp. 337-364 |
article | DOI URL |
Abstract: We examined the compositions of dissolved, fine and coarse particulate organic matter fractions (DOM, FPOM and CPOM, respectively) from 18 river sites in Peru along a 2000 km transect ranging from diverse Andean headwater environments, to depositional reaches, to the confluence of major lowland rivers that. form the Rio Amazonas proper. The objective of the study was to evaluate the extent to which compositions of the three primary OM fractions evolve downstream, with the overall goal of assessing the relative effects of various processes in the dynamics of OM within a large river system. Composition was assessed by concentration, elemental (%OC, %N, C/N), isotopic (C-13, N-15), hydrolysable amino acid, lignin phenol and mineral surface area analyses. Similar to previous results from the lower Amazon and from Bolivian tributaries, CPOM, FPOM and DOM showed distinct compositional differences from one another. However, compositions of OM size fractions at Andean sites were substantially different from lowland sites, with a clear downstream evolution in most OM properties toward typical lowland Amazon values. Andean FPOM and CPOM both had very high %OC and amino acid content, and low C/N typical of lowland FPOM. Andean UDOM showed low %OC, low C/N, high %TAAC and low non-protein amino acid content - also typical of lowland FPOM. These properties have been shown to be affected by selective partitioning onto minerals [Aufdenkampe, A.K., Hedges, J.I., Richey, J.E., Krusche, AN., Llerena, C.A., 2001. Sorptive fractionation of dissolved organic nitrogen and amino acids onto fine sediments within the Amazon Basin. Limnology and Oceanography 46 (8), 1921-1935]. In contrast, lignin phenol acid to aldehyde ratios ((Ad/Al)(v)), indicators of diagenesis, were invariant and within typical lowland values over the entire transect. Thus, we propose that differences in the extent of organo-mineral association are the most plausible explanation for these trends. In the Andes, sand-sized particles appear to be stable aggregates of fine omano-mineral complexes and Andean DOM appears to be complexed with ultra-fine inorganic colloids. Therefore, unlike in previous studies, size was not always a good proxy for the degree of mineral association. However, it appears that selective partitioning of organic carbon and nitrogen molecules may be a dominant process in controlling OM composition in these rivers. (c) 2006 Elsevier Ltd. All rights reserved. | |||||
BibTeX:
@article{aufdenkampe_organic_2007, author = {Aufdenkampe, Anthony K. and Mayorga, Emilio and Hedges, John I. and Llerena, Carlos and Quay, Paul D. and Gudeman, Jack and Krusche, Alex V. and Richey, Jeffrey E.}, title = {Organic matter in the Peruvian headwaters of the Amazon: Compositional evolution from the Andes to the lowland Amazon mainstem}, journal = {Organic Geochemistry}, year = {2007}, volume = {38}, number = {3}, pages = {337--364}, url = {://WOS:000245047500002 http://ac.els-cdn.com/S0146638006001288/1-s2.0-S0146638006001288-main.pdf?_tid=1b3b2870-03f2-11e2-8b61-00000aab0f6c&acdnat=1348235094_606e4d35f97beb51c2445d1d965523d9}, doi = {https://doi.org/10.1016/j.orggeochem.2006.06.003} } |
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Aufdenkampe, A.K., Hedges, J.I., Richey, J.E., Krusche, A.V. and Llerena, C.A. | Sorptive fractionation of dissolved organic nitrogen and amino acids onto fine sediments within the Amazon Basin | 2001 | Limnology and Oceanography Vol. 46(8), pp. 1921-1935 |
article | URL |
Abstract: A consistent observation of river waters in the Amazon Basin and elsewhere is that suspended fine particulate organic matter (FPOM) is compositionally distinct from coexisting dissolved organic matter (DOM). The present article presents experimental results that show that at least some of these compositional patterns are the outcome of selective partitioning of nitrogen-rich DOM components onto mineral surfaces. Nine laboratory experiments were conducted in which natural DOM from two rivers, one wetland, and two leachates from the Peruvian Amazon were mixed with natural suspended riverine minerals or organic-free kaolinite. Concentrations of organic carbon, organic nitrogen, and hydrolyzable amino acids were measured in both dissolved and particulate phases before and after mixing. In each of these trials, nitrogen was preferentially taken into the particulate fraction relative to the "parent" DOM, as were total hydrolyzable amino acids with respect to total organic carbon and nitrogen. Amino acid compositional patterns also indicated preferential sorption of basic amino acids, with positively charged nitrogen side chains, to the negatively charged aluminosilicate clay minerals. In short, sorption of natural DOM to minerals reproduced all contrasting organic nitrogen compositional patterns observed in the Amazon Basin. Although previously conjectured from FPOM-DOM compositional trends from river samples, this is the first direct evidence for preferential uptake of naturally occurring nitrogenous DOM by suspended riverine minerals. Last, nonprotein amino acids, which are commonly used as diagenetic indicators in sediments, preferentially remained dissolved, which suggests that sorptive fractionation may significantly complicate comparisons of FPOM and DOM diagenesis on the basis of interpretation of organic composition. | |||||
BibTeX:
@article{aufdenkampe_sorptive_2001, author = {Aufdenkampe, A. K. and Hedges, J. I. and Richey, J. E. and Krusche, A. V. and Llerena, C. A.}, title = {Sorptive fractionation of dissolved organic nitrogen and amino acids onto fine sediments within the Amazon Basin}, journal = {Limnology and Oceanography}, year = {2001}, volume = {46}, number = {8}, pages = {1921--1935}, url = {://WOS:000172466500007} } |
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Atkin, O., Meir, P. and Turnbull, M. | Improving representation of leaf respiration in large-scale predictive climate-vegetation models [BibTeX] |
2014 | New Phytologist Vol. 202(3), pp. 743-748 |
article | |
BibTeX:
@article{atkin_improving_2014, author = {Atkin, O.K. and Meir, P. and Turnbull, M.H.}, title = {Improving representation of leaf respiration in large-scale predictive climate-vegetation models}, journal = {New Phytologist}, year = {2014}, volume = {202}, number = {3}, pages = {743--748} } |
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Assunção, L.M.F.d., Manzi, A.O., Higuchi, N., Candido, L.A. and Luizão, F. | Aplicação de modelo acoplado clima-vegetação em escala local [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 113-120 |
incollection | |
BibTeX:
@incollection{emilio_aplicacao_2014, author = {Assunção, Lilia M. F. de and Manzi, Antonio O. and Higuchi, Niro and Candido, Luiz A. and Luizão, Flávio}, title = {Aplicação de modelo acoplado clima-vegetação em escala local}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {113--120}, note = {Section: 10} } |
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Assis, F., Piedade, M., Haugaasen T., R. and Wittmann | Effects of hydroperiod and substrate properties on tree alpha diversity and composition in Amazonian floodplain forests [BibTeX] |
2014 | Plant Ecology Vol. 216, pp. 41-54 |
article | |
BibTeX:
@article{assis_effects_2014, author = {Assis, F; Piedade, MTF; Haugaasen, T., RL; Wittmann}, title = {Effects of hydroperiod and substrate properties on tree alpha diversity and composition in Amazonian floodplain forests}, journal = {Plant Ecology}, year = {2014}, volume = {216}, pages = {41--54} } |
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Assahira, C., Piedade, M.T.F., Trumbore, S.E., Wittmann, F., Cintra, B.B.L., Batista, E.S., Resende, A.F.d. and Schöngart, J. | Tree mortality of a flood-adapted species in response of hydrographic changes caused by an Amazonian river dam [BibTeX] |
2017 | Forest Ecology and Management Vol. 396, pp. 113-123 |
article | |
BibTeX:
@article{assahira_tree_2017, author = {Assahira, C. and Piedade, M. T. F. and Trumbore, S. E. and Wittmann, F. and Cintra, B. B. L. and Batista, E. S. and Resende, A. F. de and Schöngart, J.}, title = {Tree mortality of a flood-adapted species in response of hydrographic changes caused by an Amazonian river dam}, journal = {Forest Ecology and Management}, year = {2017}, volume = {396}, pages = {113--123} } |
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Asner, G.P. and Warner, A.S. | Canopy shadow in IKONOS satellite observations of tropical forests and savannas | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 521-533 |
article | DOI URL |
Abstract: The biological and structural complexity of tropical forests and savannas results in marked spatial variation in shadows inherent to remotely sensed measurements. While the biophysical and observational factors driving variations in apparent shadow are known, little quantitative information exists on the magnitude and variability of shadow in remotely sensed data acquired over tropical regions. Even less is known about shadow effects in multispectral observations from satellites (e.g., Landsat). The IKONOS satellite, with 1-m panchromatic and 4-m multispectral capabilities, provides an opportunity to observe tropical canopies and their shadows at spatial scales approaching the size of individual crowns and vegetation clusters. We used 44 IKONOS images from the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) data archive to quantify the spatial variation of canopy shadow fraction across a broad range of forests in the Brazilian Amazon and savannas in the Brazilian Cerrado. Forests had substantial apparent shadow fractions as viewed from the satellite vantage point. The global mean (+/-S.D.) shadow fraction was 0.25 +/- 0.12, and within-scene (e.g., forest stand) variability was similar to interscene (e.g., regional) variation. The distribution of shadow fractions for forest stands was skewed, with 30% of pixels having fractional shadow values above 0.30. Shadow fractions in savannas increased from 0.0 +/- 0.0 1 to 0.12 +/- 0.04 to 0.16 +/- 0.05 for areas with woody vegetation at low (textless25% cover), medium (25-75%), and high (textgreater75%) density, respectively. Landsat-like observations using both red (0.63-0.70 mum) and near-infrared (NIR) (0.76-0.85 mum) wavelength regions were highly sensitive to sub-pixel shadow fractions in tropical forests, accounting for similar to30-50% of the variance in red and NIR responses. A 10% increase in shadow fraction resulted in a 3% and 10% decrease in red and NIR channel response, respectively. The normalized difference vegetation index (NDVI) of tropical forests was weakly sensitive to changes in shadow fraction. For low-, medium-, and high-density savannas,a 10% increase in shadow fraction resulted in a 5-7% decrease in red-channel response. Shadows accounted for similar to15-50% of the overall variance in red-wavelength responses in the savanna image archive. Weak to no relationship occurred between shadow fraction and either NIR reflectance or the NDVI of savannas. Quantitative information on shadowing is needed to validate or constrain radiative transfer, spectral mixture, and land-surface models used to estimate material and energy exchanges between the tropical biosphere and atmosphere. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{asner_canopy_2003, author = {Asner, G. P. and Warner, A. S.}, title = {Canopy shadow in IKONOS satellite observations of tropical forests and savannas}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {521--533}, url = {://WOS:000186827400011 http://ac.els-cdn.com/S0034425703002104/1-s2.0-S0034425703002104-main.pdf?_tid=0f176630-03f2-11e2-94dc-00000aab0f6c&acdnat=1348235074_d54cd3d76ac6beae493a0ba96746ec6f}, doi = {https://doi.org/10.1016/j.rse.2003.08.006} } |
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Asner, G.P., Townsend, A.R., Riley, W.J., Matson, P.A., Neff, J.C. and Cleveland, C.C. | Physical and biogeochemical controls over terrestrial ecosystem responses to nitrogen deposition | 2001 | Biogeochemistry Vol. 54(1), pp. 1-39 |
article | DOI URL |
Abstract: Anthropogenic perturbations to the global nitrogen (N) cycle now exceed those to any other major biogeochemical cycle on Earth, yet our ability to predict how ecosystems will respond to the rapidly changing N cycle is still poor. While northern temperate forest ecosystems have seen the greatest changes in N inputs from the atmosphere, other biomes, notably semi-arid and tropical regions of the globe, are now experiencing increases in N deposition. These systems are even less well understood than temperate forests, and are likely to respond to excess N in markedly different ways. Here, we present a new integrated terrestrial biophysics-biogeochemical process model, TerraFlux, and use this model to test the relative importance of factors that may strongly influence the productivity response of both humid tropical and semi-arid systems to anthropogenic N deposition. These include hydrological losses of dissolved inorganic and organic N, as well as multiple nutrient interactions with deposited inorganic N along the hydrological pathway. Our results suggest that N-rich tropical forests may have reduced productivity following excess N deposition. Our simulations of semi-arid systems show increases in productivity following N inputs if water availability is sufficient and water losses are moderate. The most important model controls over the carbon cycle response in each simulation were interactions that are not represented in the most common terrestrial ecosystem models. These include parameters that control soil solute transport and nutrient resorption by plants. Rather than attempt prognostic simulations, we use TerraFlux to highlight a variety of ecological and biogeochemical processes that are poorly understood but which appear central to understanding ecosystem response to excess N. | |||||
BibTeX:
@article{asner_physical_2001, author = {Asner, G. P. and Townsend, A. R. and Riley, W. J. and Matson, P. A. and Neff, J. C. and Cleveland, C. C.}, title = {Physical and biogeochemical controls over terrestrial ecosystem responses to nitrogen deposition}, journal = {Biogeochemistry}, year = {2001}, volume = {54}, number = {1}, pages = {1--39}, url = {://WOS:000168666900001 http://www.springerlink.com/content/u27474h2h9370043/fulltext.pdf}, doi = {https://doi.org/10.1023/a:1010653913530} } |
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Asner, G.P., Townsend, A.R., Bustamante, M.M.C., Nardoto, G.B. and Olander, L.P. | Pasture degradation in the central Amazon: linking changes in carbon and nutrient cycling with remote sensing | 2004 | Global Change Biology Vol. 10(5), pp. 844-862 |
article | DOI URL |
Abstract: The majority of deforested land in the Amazon Basin has become cattle pasture, making forest-to-pasture conversion an important contributor to the carbon (C) and climate dynamics of the region. However, our understanding of biogeochemical dynamics in pasturelands remains poor, especially when attempting to scale up predictions of C cycle changes. A wide range of pasture ages, soil types, management strategies, and climates make remote sensing the only realistic means to regionalize our understanding of pasture biogeochemistry and C cycling over such an enormous geographic area. However, the use of remote sensing has been impeded by a lack of effective links between variables that can be observed from satellites (e.g. live and senescent biomass) and variables that cannot be observed, but which may drive key changes in C storage and trace gas fluxes (e.g. soil nutrient status). We studied patterns in canopy biophysical-biochemical properties and soil biogeochemical processes along pasture age gradients on two important soil types in the central Amazon. Our goals were to (1) improve our understanding of the plot-scale biogeochemical dynamics of this land-use change, (2) evaluate the effects of pasture development on two contrasting soil types (clayey Oxisols and sandy Entisols), and (3) attempt to use remotely sensed variables to scale up the site-specific variability in biogeochemical conditions of pasturelands. The biogeochemical analyses showed that (1) aboveground and soil C stocks decreased with pasture age on both clayey and sandy soils, (2) declines in plant biomass were well correlated with declines in soil C and with available phosphorus (P) and calcium (Ca), and (3) despite low initial values for total and available soil P, ecosystem P stocks declined further with pasture age, as did a number of other nutrients. Spectral mixture analysis of Landsat imagery provided estimates of photosynthetic vegetation (PV) and non-photosynthetic vegetation (NPV) that were highly correlated with field measurements of these variables and plant biomass. In turn, the remotely sensed sum PV+NPV was well correlated with the changes in soil organic carbon and nitrogen, and available P and Ca. These results suggest that remote sensing can be an excellent indicator of not only pasture area, but of pasture condition and C storage, thereby greatly improving regional estimates of the environmental consequences of such land-use change. | |||||
BibTeX:
@article{asner_pasture_2004, author = {Asner, G. P. and Townsend, A. R. and Bustamante, M. M. C. and Nardoto, G. B. and Olander, L. P.}, title = {Pasture degradation in the central Amazon: linking changes in carbon and nutrient cycling with remote sensing}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {844--862}, url = {://WOS:000221421600022 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00766.x/asset/j.1529-8817.2003.00766.x.pdf?v=1&t=h6hxh19c&s=02df04d4e7ad6351a91b82b0d030a6a16f918ada}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00766.x} } |
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Asner, G.P., Townsend, A.R. and Bustamante, M.M.C. | Spectrometry of pasture condition and biogeochemistry in the Central Amazon | 1999 | Geophysical Research Letters Vol. 26(17), pp. 2769-2772 |
article | DOI URL |
Abstract: Regional analyses of Amazon cattle pasture biogeochemistry are difficult due to the complexity of human, edaphic, biotic and climatic factors and persistent cloud cover in satellite observations. We developed a method to estimate key biophysical properties of Amazon pastures using hyperspectral reflectance data and photon transport inverse modeling. Remote estimates of live and senescent biomass were strongly correlated with plant-available forms of soil phosphorus and calcium. These results provide a basis for monitoring pasture condition and biogeochemistry in the Amazon Basin using spaceborne hyperspectral sensors. | |||||
BibTeX:
@article{asner_spectrometry_1999, author = {Asner, G. P. and Townsend, A. R. and Bustamante, M. M. C.}, title = {Spectrometry of pasture condition and biogeochemistry in the Central Amazon}, journal = {Geophysical Research Letters}, year = {1999}, volume = {26}, number = {17}, pages = {2769--2772}, url = {://WOS:000082391100034 http://www.agu.org/pubs/crossref/1999/1999GL900546.shtml}, doi = {https://doi.org/10.1029/1999gl900546} } |
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Asner, G.P., Townsend, A.R. and Braswell, B.H. | Satellite observation of El Nino effects on Amazon forest phenology and productivity | 2000 | Geophysical Research Letters Vol. 27(7), pp. 981-984 |
article | DOI URL |
Abstract: Climate variability may affect the functioning of Amazon moist tropical forests, and recent modeling analyses suggest that the carbon dynamics of the region vary interannually in response to precipitation and temperature anomalies. However, due to persistent orbital and atmospheric artifacts in the satellite record, remote sensing observations have not provided quantitative evidence that climate variation affects Amazon forest phenology or productivity. We developed a method to minimize and quantify non-biological artifacts in NOAA AVHRR satellite data, providing a record of estimated forest phenological variation from 1982-1993. The seasonal NDVI amplitude (a proxy for phenology) increased throughout much of the basin during El Nino periods when rainfall was anomalously low. Wetter La Nina episodes brought consistently smaller NDVI amplitudes. Using radiative transfer and terrestrial biogeochemical models driven by these satellite data, we estimate that canopy energy absorption and net primary production of Amazon forests varied interannually by as much as 21% and 18%, respectively. These results provide large-scale observational evidence for interannual sensitivity to El Nino of plant phenology and carbon flux in Amazon forests. | |||||
BibTeX:
@article{asner_satellite_2000, author = {Asner, G. P. and Townsend, A. R. and Braswell, B. H.}, title = {Satellite observation of El Nino effects on Amazon forest phenology and productivity}, journal = {Geophysical Research Letters}, year = {2000}, volume = {27}, number = {7}, pages = {981--984}, url = {://WOS:000086224500019 http://www.agu.org/pubs/crossref/2000/1999GL011113.shtml}, doi = {https://doi.org/10.1029/1999gl011113} } |
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Asner, G.P., Powell, G.V.N., Mascaro, J., Knapp, D.E., Clark, J.K., Jacobson, J., Kennedy-Bowdoin, T., Balaji, A., Paez-Acosta, G., Victoria, E., Secada, L., Valqui, M. and Hughes, R.F. | High-resolution forest carbon stocks and emissions in the Amazon | 2010 | Proceedings of the National Academy of Sciences of the United States of America Vol. 107(38), pp. 16738-16742 |
article | DOI URL |
Abstract: Efforts to mitigate climate change through the Reduced Emissions from Deforestation and Degradation (REDD) depend on mapping and monitoring of tropical forest carbon stocks and emissions over large geographic areas. With a new integrated use of satellite imaging, airborne light detection and ranging, and field plots, we mapped aboveground carbon stocks and emissions at 0.1-ha resolution over 4.3 million ha of the Peruvian Amazon, an area twice that of all forests in Costa Rica, to reveal the determinants of forest carbon density and to demonstrate the feasibility of mapping carbon emissions for REDD. We discovered previously unknown variation in carbon storage at multiple scales based on geologic substrate and forest type. From 1999 to 2009, emissions from land use totaled 1.1% of the standing carbon throughout the region. Forest degradation, such as from selective logging, increased regional carbon emissions by 47% over deforestation alone, and secondary regrowth provided an 18% offset against total gross emissions. Very high-resolution monitoring reduces uncertainty in carbon emissions for REDD programs while uncovering fundamental environmental controls on forest carbon storage and their interactions with land-use change. | |||||
BibTeX:
@article{asner_high-resolution_2010, author = {Asner, Gregory P. and Powell, George V. N. and Mascaro, Joseph and Knapp, David E. and Clark, John K. and Jacobson, James and Kennedy-Bowdoin, Ty and Balaji, Aravindh and Paez-Acosta, Guayana and Victoria, Eloy and Secada, Laura and Valqui, Michael and Hughes, R. Flint}, title = {High-resolution forest carbon stocks and emissions in the Amazon}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2010}, volume = {107}, number = {38}, pages = {16738--16742}, note = {Edition: 2010/09/09}, url = {://WOS:000282003700064 http://www.pnas.org/content/107/38/16738.full.pdf}, doi = {https://doi.org/10.1073/pnas.1004875107} } |
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Asner, G.P., Palace, M., Keller, M., Pereira, R., Silva, J.N.M. and Zweede, J.C. | Estimating canopy structure in an Amazon Forest from laser range finder and IKONOS satellite observations | 2002 | Biotropica Vol. 34(4), pp. 483-492 |
article | DOI URL |
Abstract: Canopy structural data can be used for biomass estimation and studies of carbon cycling, disturbance, energy balance, and hydrological processes in tropical forest ecosystems. Scarce information on canopy dimensions reflects the difficulties associated with measuring crown height, width, depth, and area in tall, humid tropical forests. New field and spaceborne observations provide an opportunity to acquire these measurements, but the accuracy and reliability of the methods are unknown. We used a handheld laser range finder to estimate tree crown height, diameter, and depth in a lowland tropical forest in the eastern Amazon, Brazil, for a sampling of 300 trees stratified by diameter at breast height (DBH). We found significant relationships between DBH and both tree height and crown diameter derived from the laser measurements. We also quantified changes in crown shape between tree height classes, finding a significant but weak positive trend between crown depth and width. We then compared the field-based measurements of crown diameter and area to estimates derived manually from panchromatic 0.8 m spatial resolution IKONOS satellite imagery. Median crown diameter derived from satellite observations was 78 percent greater than that derived from field-based laser measurements. The statistical distribution of crown diameters from IKONOS was biased toward larger trees, probably due to merging of smaller tree crowns, underestimation of understory trees, and overestimation of individual crown dimensions. The median crown area derived front IKONOS was 65 percent higher than the value modeled from field-based measurements. We conclude that manual interpretation of IKONOS satellite data did not accurately estimate distributions of tree crown dimensions in a tall tropical forest of eastern Amazonia. Other methods will be needed to more accurately estimate crown dimensions from high spatial resolution satellite imagery. | |||||
BibTeX:
@article{asner_estimating_2002, author = {Asner, G. P. and Palace, M. and Keller, M. and Pereira, R. and Silva, J. N. M. and Zweede, J. C.}, title = {Estimating canopy structure in an Amazon Forest from laser range finder and IKONOS satellite observations}, journal = {Biotropica}, year = {2002}, volume = {34}, number = {4}, pages = {483--492}, url = {://WOS:000180539800002 http://onlinelibrary.wiley.com/store/10.1111/j.1744-7429.2002.tb00568.x/asset/j.1744-7429.2002.tb00568.x.pdf?v=1&t=h6hxf88t&s=87a70255c1be67dc8ec73856d884c121aa740323}, doi = {https://doi.org/10.1111/j.1744-7429.2002.tb00568.x} } |
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Asner, G.P., Nepstad, D., Cardinot, G. and Ray, D. | Drought stress and carbon uptake in an Amazon forest measured with spaceborne imaging spectroscopy | 2004 | Proceedings of the National Academy of Sciences of the United States of America Vol. 101(16), pp. 6039-6044 |
article | DOI URL |
Abstract: Amazonia contains vast stores of carbon in high-diversity ecosystems, yet this region undergoes major changes in precipitation affecting land use, carbon dynamics, and climate. The extent and structural complexity of Amazon forests impedes ground studies of ecosystem functions such as net primary production (NPP), water cycling, and carbon sequestration. Traditional modeling and remote-sensing approaches are not well suited to tropical forest studies, because (i) biophysical mechanisms determining drought effects on canopy water and carbon dynamics are poorly known, and (ii) remote-sensing metrics of canopy greenness may be insensitive to small changes in leaf area accompanying drought. New spaceborne imaging spectroscopy may detect drought stress in tropical forests, helping to monitor forest physiology and constrain carbon models. We combined a forest drought experiment in Amazonia with spaceborne imaging spectrometer measurements of this area. With field data on rainfall, soil water, and leaf and canopy responses, we tested whether spaceborne hyperspectral observations quantify differences in canopy water and NIPP resulting from drought stress. We found that hyperspectral metrics of canopy water content and light-use efficiency are highly sensitive to drought. Using these observations, forest NIPP was estimated with greater sensitivity to drought conditions than with traditional combinations of modeling, remote-sensing, and field measurements. Spaceborne imaging spectroscopy will increase the accuracy of ecological studies in humid tropical forests. | |||||
BibTeX:
@article{asner_drought_2004, author = {Asner, G. P. and Nepstad, D. and Cardinot, G. and Ray, D.}, title = {Drought stress and carbon uptake in an Amazon forest measured with spaceborne imaging spectroscopy}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2004}, volume = {101}, number = {16}, pages = {6039--6044}, note = {Edition: 2004/04/09}, url = {://WOS:000220978000066 http://www.pnas.org/content/101/16/6039.full.pdf}, doi = {https://doi.org/10.1073/pnas.0400168101} } |
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Asner, G.P., Mascaro, J., Clark, J.K. and Powell, G. | Reply to Skole et al.: Regarding high-resolution carbon stocks and emissions in the Amazon [BibTeX] |
2011 | Proceedings of the National Academy of Sciences of the United States of America Vol. 108(4), pp. E13-E14 |
article | DOI URL |
BibTeX:
@article{asner_reply_2011, author = {Asner, Gregory P. and Mascaro, Joseph and Clark, John K. and Powell, George}, title = {Reply to Skole et al.: Regarding high-resolution carbon stocks and emissions in the Amazon}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2011}, volume = {108}, number = {4}, pages = {E13--E14}, url = {://WOS:000286594800002 http://www.pnas.org/content/108/4/E13.full.pdf}, doi = {https://doi.org/10.1073/pnas.1017675108} } |
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Asner, G.P., Knapp, D.E., Cooper, A.N., Bustamante, M.M.C. and Olander, L.P. | Ecosystem structure throughout the Brazilian amazon from Landsat observations and automated spectral unmixing | 2005 | Earth Interactions Vol. 9 |
article | URL |
Abstract: The Brazilian Amazon forest and cerrado savanna encompasses a region of enormous ecological, climatic, and land-use variation. Satellite remote sensing is the only tractable means to measure the biophysical attributes of vegetation throughout this region, but coarse-resolution sensors cannot resolve the details of forest structure and land-cover change deemed critical to many land-use, ecological, and conservation-oriented studies. The Carnegie Landsat Analysis System (CLAS) was developed for studies of forest and savanna structural attributes using widely available Landsat Enhanced Thematic Mapper Plus (ETM+) satellite data and advanced methods in automated spectral mixture analysis. The methodology of the CLAS approach is presented along with a study of its sensitivity to atmospheric correction errors. CLAS is then applied to a mosaic of Landsat images spanning the years 1999 - 2001 as a proof of concept and capability for large-scale, very high resolution mapping of the Amazon and bordering cerrado savanna. A total of 197 images were analyzed for fractional photosynthetic vegetation (PV), non-photosynthetic vegetation (NPV), and bare substrate covers using a probabilistic spectral mixture model. Results from areas without significant land use, clouds, cloud shadows, and water bodies were compiled by the Brazilian state and vegetation class to understand the baseline structural typology of forests and savannas using this new system. Conversion of the satellite-derived PV data to woody canopy gap fraction was made to highlight major differences by vegetation and ecosystem classes. The results indicate important differences in fractional photosynthetic cover and canopy gap fraction that can now be accounted for in future studies of land-cover change, ecological variability, and biogeochemical processes across the Amazon and bordering cerrado regions of Brazil. | |||||
BibTeX:
@article{asner_ecosystem_2005, author = {Asner, Gregory P. and Knapp, David E. and Cooper, Amanda N. and Bustamante, Mercedes M. C. and Olander, Lydia P.}, title = {Ecosystem structure throughout the Brazilian amazon from Landsat observations and automated spectral unmixing}, journal = {Earth Interactions}, year = {2005}, volume = {9}, url = {://WOS:000241212800001} } |
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Asner, G.P., Knapp, D.E., Broadbent, E.N., Oliveira, P.J.C., Keller, M. and Silva, J.N. | Selective logging in the Brazilian Amazon | 2005 | Science Vol. 310(5747), pp. 480-482 |
article | DOI URL |
Abstract: Amazon deforestation has been measured by remote sensing for three decades. in comparison, selective logging has been mostly invisible to satellites. We developed a large-scale, high-resolution, automated remote-sensing analysis of selective logging in the top five timber-producing states of the Brazilian Amazon. Logged areas ranged from 12,075 to 19,823 square kilometers per year (+/- 14%) between 1999 and 2002, equivalent to 60 to 123% of previously reported deforestation area. Up to 1200 square kilometers per year of logging were observed on conservation lands. Each year, 27 million to 50 million cubic meters of wood were extracted, and a gross flux of similar to 0.1 billion metric tons of carbon was destined for release to the atmosphere by logging. | |||||
BibTeX:
@article{asner_selective_2005, author = {Asner, G. P. and Knapp, D. E. and Broadbent, E. N. and Oliveira, P. J. C. and Keller, M. and Silva, J. N.}, title = {Selective logging in the Brazilian Amazon}, journal = {Science}, year = {2005}, volume = {310}, number = {5747}, pages = {480--482}, note = {Edition: 2005/10/22}, url = {://WOS:000232786000043 http://www.sciencemag.org/content/310/5747/480}, doi = {https://doi.org/10.1126/science.1118051} } |
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Asner, G.P., Keller, M. and Silva, J.N.M. | Spatial and temporal dynamics of forest canopy gaps following selective logging in the eastern Amazon | 2004 | Global Change Biology Vol. 10(5), pp. 765-783 |
article | DOI URL |
Abstract: Selective logging is a dominant form of land use in the Amazon basin and throughout the humid tropics, yet little is known about the spatial variability of forest canopy gap formation and closure following timber harvests. We established chronosequences of large-area (14-158 ha) selective logging sites spanning a 3.5-year period of forest regeneration and two distinct harvest methods: conventional logging (CL) and reduced-impact logging (RIL). Our goals were to: (1) determine the spatial characteristics of canopy gap fraction immediately following selective logging in the eastern Amazon; (2) determine the degree and rate of canopy closure in early years following harvest among the major landscape features associated with logging - tree falls, roads, skid trails and log decks; and (3) quantify spatial and temporal differences in canopy opening and closure in high- and low-damage harvests (CL vs. RIL). Across a wide range of harvest intensities (2.6-6.4 felled trees ha(-1)), the majority of ground damage occurred as skid trails (4-12%), whereas log decks and roads were only a small contributor to the total ground damage (textless2%). Despite similar timber harvest intensities, CL resulted in more ground damage than RIL. Neither the number of log decks nor their individual or total area was correlated with the number of trees removed or intensity of tree harvesting (trees ha(-1)). The area of skids was well correlated with the ground area damaged (m(2)) per tree felled. In recently logged forest (0.5 years postharvest), gap fractions were highest in log decks (mean RIL=0.83, CL=0.99) and lowest in tree-fall areas (RIL: 0.26, CL: 0.41). However, the small surface area of log decks made their contribution to the total area-integrated forest gap fraction minor. In contrast, tree falls accounted for more than two-thirds of the area disturbed, but the canopy gaps associated with felled trees were much smaller than for log decks, roads and skids. Canopy openings decreased in size with distance from each felled tree crown. At 0.5 years postharvest, the area initially affected by the felling of each tree was approximately 100 m in radius for CL and 50 m for RIL. Initial decreases in gap fraction during the first 1.5 years of regrowth diminished in subsequent years. Throughout the 3.5-year period of forest recovery, tree-fall gap fractions remained higher in CL than in RIL treatments, but canopy gap closure rates were higher in CL than in RIL areas. During the observed recovery period, the canopy gap area affected by harvesting decreased in radius around each felled tree from 100 to 40 m in CL, and from 50 to 10 m in RIL. The results suggest that the full spatial and temporal dynamics of canopy gap fraction must be understood and monitored to predict the effects of selective logging on regional energy balance and climate regimes, biogeochemical processes including carbon cycling, and plant and faunal population dynamics. This paper also shows that remote sensing of log decks alone will not provide an accurate assessment of total forest area impacted by selective logging, nor will it be closely correlated to damage levels and canopy gap closure rates. | |||||
BibTeX:
@article{asner_spatial_2004, author = {Asner, G. P. and Keller, M. and Silva, J. N. M.}, title = {Spatial and temporal dynamics of forest canopy gaps following selective logging in the eastern Amazon}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {765--783}, url = {://WOS:000221421600017 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00756.x/asset/j.1529-8817.2003.00756.x.pdf?v=1&t=h6hxdi7g&s=7099fb4af442690ee4f759484ef51c90df1d3d5b}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00756.x} } |
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Asner, G.P., Keller, M., Pereira, R., Zweede, J.C. and Silva, J.N.M. | Canopy damage and recovery after selective logging in Amazonia: Field and satellite studies | 2004 | Ecological Applications Vol. 14(4), pp. S280-S298 |
article | URL |
Abstract: We combined a detailed field study of canopy gap fraction with spectral mixture analyses of Landsat 7 ETM+ satellite imagery to assess landscape and regional dynamics of canopy damage following selective logging in an eastern Amazon forest. Our field studies encompassed measurements of ground damage and canopy gap fractions along multitemporal sequences of post-harvest regrowth of 0.5-3.5 yr. Areas used to stage harvested logs prior to transport, called log decks, had the largest forest gap fractions, but their contribution to the landscape-level gap dynamics was minor. Tree falls were spatially the most extensive form of canopy damage following selective logging, but the canopy gap fractions resulting from them were small. Reduced-impact logging resulted in consistently less damage to the forest canopy than did conventional logging practices. This was true at the level of individual landscape strata such as roads, skids, and tree falls as well as at the area-integrated scale. A spectral mixture model was employed that utilizes bundles of field and image spectral reflectance measurements with Monte Carlo analysis to estimate high spatial resolution (subpixel) cover of forest canopies, exposed norphotosynthetic vegetation, and soils in the Landsat imagery. The method proved highly useful for quantifying forest canopy cover fraction in log decks, roads, skids, tree fall, and intact forest areas, and it tracked canopy damage up to 3.5 yr post-harvest. Forest canopy cover fractions derived from the satellite observations were highly and inversely correlated with field-based canopy gap fraction. Subsequent regional-scale estimates of forest gap fraction were derived from the combination of field- and satellite-based measurements. A 450-km(2) study of gap fraction showed that approximately one-half of the canopy opening caused by logging is closed within one year of regrowth following timber harvests. This is the first regional-scale study utilizing field measurements, satellite observations, and models to quantify forest canopy damage and recovery following selective logging in the Amazon. | |||||
BibTeX:
@article{asner_canopy_2004, author = {Asner, G. P. and Keller, M. and Pereira, R. and Zweede, J. C. and Silva, J. N. M.}, title = {Canopy damage and recovery after selective logging in Amazonia: Field and satellite studies}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S280--S298}, url = {://WOS:000223269000023} } |
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Asner, G.P., Keller, M., Pereira, R. and Zweede, J.C. | Remote sensing of selective logging in Amazonia - Assessing limitations based on detailed field observations, Landsat ETM+, and textural analysis | 2002 | Remote Sensing of Environment Vol. 80(3), pp. 483-496 |
article | DOI URL |
Abstract: We combined a detailed Field study of forest canopy damage with calibrated Landsat 7 Enhanced Thematic Mapper Plus (ETM+) reflectance data and texture analysis to assess the sensitivity of basic broadband optical remote sensing to selective logging in Amazonia. Our Field study encompassed measurements of ground damage and canopy gap fractions along a chronosequence of postharvest regrowth of 0.5 - 3.5 years. We found that canopy damage and regrowth rates varied according to the logging method used, either conventional logging or reduced impact logging. Areas used to stage felled trees prior to transport, log decks, had the largest gap fractions immediately following cutting. Log decks were quickly colonized by early successional plant species, resulting in significant gap fraction decreases within 1.5 years after site abandonment. Although log decks were the most obvious damage areas on the ground and in satellite imagery, they accounted for only 1-2% of the total harvested area of the blocks studied. Other forest damage features such as tree-fall gaps, skid trails, and roads were difficult to recognize in Landsat reflectance data or through textural analysis. These landscape features could be only crudely resolved in the most intensively logged forests and within about 0.5 years following harvest. We found that forest damage within any of the landscape strata (decks, roads, skids, tree falls) could not be resolved with Landsat reflectance or texture data when the canopy gap fraction was textless 50%. The basic Landsat ETM+ imagery lacks the resolution of forest structural features required for quantitative studies of logging damage. Landsat textural analyses may be useful for broad delineation of logged forests, but detailed ecological and biogeochemical studies will probably need to rely on other remote sensing approaches. Until spatial gradients of canopy damage and regrowth resulting from selective logging operations in tropical forests in the Amazon region are resolved, the impacts of this land use on a continental scale will remain poorly understood. (C) 2002 Elsevier Science Inc. All rights reserved. | |||||
BibTeX:
@article{asner_remote_2002, author = {Asner, G. P. and Keller, M. and Pereira, R. and Zweede, J. C.}, title = {Remote sensing of selective logging in Amazonia - Assessing limitations based on detailed field observations, Landsat ETM+, and textural analysis}, journal = {Remote Sensing of Environment}, year = {2002}, volume = {80}, number = {3}, pages = {483--496}, url = {://WOS:000175757700011 http://ac.els-cdn.com/S0034425701003261/1-s2.0-S0034425701003261-main.pdf?_tid=027de3e0-03f2-11e2-a825-00000aacb360&acdnat=1348235053_21f031fcbddf3dba071cd7c41ea66c1e}, doi = {https://doi.org/10.1016/s0034-4257(01)00326-1} } |
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Asner, G.P., Keller, M., Lentini, M., Merry, F. and Souza Jr., C. | Selective Logging and Its Relation to Deforestation [BibTeX] |
2009 | (Geophysical Monograph 186)Amazonia and Global Change, pp. 25-42 | incollection | |
BibTeX:
@incollection{ed_m_keller_selective_2009, author = {Asner, Gregory P. and Keller, Michael and Lentini, Marco and Merry, Frank and Souza Jr., Carlos}, title = {Selective Logging and Its Relation to Deforestation}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, number = {Geophysical Monograph 186}, pages = {25--42} } |
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Asner, G.P., Hughes, R.F., Vitousek, P.M., Knapp, D.E., Kennedy-Bowdoin, T., Boardman, J., Martin, R.E., Eastwood, M. and Green, R.O. | Invasive plants transform the three-dimensional structure of rain forests | 2008 | Proceedings of the National Academy of Sciences of the United States of America Vol. 105(11), pp. 4519-4523 |
article | DOI URL |
Abstract: Biological invasions contribute to global environmental change, but the dynamics and consequences of most invasions are difficult to assess at regional scales. We deployed an airborne remote sensing system that mapped the location and impacts of five highly invasive plant species across 221,875 ha of Hawaiian ecosystems, identifying four distinct ways that these species transform the three-dimensional (3D) structure of native rain forests. In lowland to montane forests, three invasive tree species replace native midcanopy and understory plants, whereas one understory invader excludes native species at the ground level. A fifth invasive nitrogen-fixing tree, in combination with a midcanopy alien tree, replaces native plants at all canopy levels in lowland forests. We conclude that this diverse array of alien plant species, each representing a different growth form or functional type, is changing the fundamental 3D structure of native Hawaiian rain forests. Our work also demonstrates how an airborne mapping strategy can identify and track the spread of certain invasive plant species, determine ecological consequences of their proliferation, and provide detailed geographic information to conservation and management efforts. | |||||
BibTeX:
@article{asner_invasive_2008, author = {Asner, Gregory P. and Hughes, R. Flint and Vitousek, Peter M. and Knapp, David E. and Kennedy-Bowdoin, Ty and Boardman, Joseph and Martin, Roberta E. and Eastwood, Michael and Green, Robert O.}, title = {Invasive plants transform the three-dimensional structure of rain forests}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2008}, volume = {105}, number = {11}, pages = {4519--4523}, note = {Edition: 2008/03/05}, url = {://WOS:000254263300079 http://www.pnas.org/content/105/11/4519.full.pdf}, doi = {https://doi.org/10.1073/pnas.0710811105} } |
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Asner, G.P., Elmore, A.J., Olander, L.P., Martin, R.E. and Harris, A.T. | Grazing systems, ecosystem responses, and global change | 2004 | Annual Review of Environment and Resources Vol. 29, pp. 261-299 |
article | DOI URL |
Abstract: Managed grazing covers more than 25% of the global land surface and has a larger geographic extent than any other form of land use. Grazing systems persist under marginal bioclimatic and edaphic conditions of different biomes, leading to the emergence of three regional syndromes inherent to global grazing: desertification, woody encroachment, and deforestation. These syndromes have widespread but differential effects on the structure, biogeocheimistry, hydrology, and biosphere-atmosphere exchange of grazed ecosystems. In combination, these three syndromes represent a major component of global environmental change. | |||||
BibTeX:
@article{asner_grazing_2004, author = {Asner, G. P. and Elmore, A. J. and Olander, L. P. and Martin, R. E. and Harris, A. T.}, title = {Grazing systems, ecosystem responses, and global change}, journal = {Annual Review of Environment and Resources}, year = {2004}, volume = {29}, pages = {261--299}, url = {://WOS:000225744400009}, doi = {https://doi.org/10.1146/annurev.energy.29.062403.102142} } |
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Asner, G.P., Bustamante, M.M.C. and Townsend, A.R. | Scale dependence of biophysical structure in deforested areas bordering the Tapajo's National Forest, Central Amazon | 2003 | Remote Sensing of Environment Vol. 87(4), pp. 507-520 |
article | DOI URL |
Abstract: Spatial variation of land-surface properties is a major challenge to ecological and biogeochemical studies in the Amazon basin. The scale dependence of biophysical variation (e.g., mixtures of vegetation cover types), as depicted in Landsat observations, was assessed for the common land-cover types bordering the Tapajos National Forest, Central Brazilian Amazon. We first collected hyperspectral signatures of vegetation and soils contributing to the optical reflectance of landscapes in a 600-km(2) region. We then employed a spectral mixture model AutoMCU that utilizes bundles of the field spectra with Monte Carlo analysis to estimate sub-pixel cover of green plants, senescent vegetation and soils in Landsat Thematic Mapper (TM) pixels. The method proved useful for quantifying biophysical variability within and between individual land parcels (e.g., across different pasture conditions). Image textural analysis was then performed to assess surface variability at the inter-pixel scale. We compared the results from the textural analysis (inter-pixel scale) to spectral mixture analysis (sub-pixel scale). We tested the hypothesis that very high resolution, sub-pixel estimates of surface constituents are needed to detect important differences in the biophysical structure of deforested lands. Across a range of deforestation categories common to the region, there was strong correlation between the fractional green and senescent vegetation cover values derived from spectral unmixing and texture analysis variance results (r(2) textgreater 0.85, p textless 0.05). These results support the argument that, in deforested areas, biophysical heterogeneity at the scale of individual field plots (sub-pixel) is similar to that of whole clearings when viewed from the Landsat vantage point. (C) 2003 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{asner_scale_2003, author = {Asner, G. P. and Bustamante, M. M. C. and Townsend, A. R.}, title = {Scale dependence of biophysical structure in deforested areas bordering the Tapajo's National Forest, Central Amazon}, journal = {Remote Sensing of Environment}, year = {2003}, volume = {87}, number = {4}, pages = {507--520}, url = {://WOS:000186827400010 http://ac.els-cdn.com/S0034425703002098/1-s2.0-S0034425703002098-main.pdf?_tid=fae5aeba-03f1-11e2-a982-00000aacb35f&acdnat=1348235040_cda9c27012d38c752cd81d63cf45424f}, doi = {https://doi.org/10.1016/j.rse.2003.03.001} } |
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Asner, G., Broadbent, E., Oliveira, P.J.C., Keller, M., Knapp, D.E. and Silva, J.N.M. | Condition and fate of logged forests in the Brazilian Amazon | 2006 | Proceedings of the National Academy of Sciences of the United States of America Vol. 103(34), pp. 12947-12950 |
article | DOI URL |
Abstract: The long-term viability of a forest industry in the Amazon region of Brazil depends on the maintenance of adequate timber volume and growth in healthy forests. Using extensive high-resolution satellite analyses, we studied the forest damage caused by recent logging operations and the likelihood that logged forests would be cleared within 4 years after timber harvest. Across 2,030,637 km(2) of the Brazilian Amazon from 1999 to 2004, at least 76% of all harvest practices resulted in high levels of canopy damage sufficient to leave forests susceptible to drought and fire. We found that 16 +/- 1% of selectively logged areas were deforested within 1 year of logging, with a subsequent annual deforestation rate of 5.4% for 4 years after timber harvests. Nearly all logging occurred within 25 km of main roads, and within that area, the probability of deforestation for a logged forest was up to four times greater than for unlogged forests. In combination, our results show that logging in the Brazilian Amazon is dominated by highly damaging operations, often followed rapidly by deforestation decades before forests can recover sufficiently to produce timber for a second harvest. Under the management regimes in effect at the time of our study in the Brazilian Amazon, selective logging would not be sustained. | |||||
BibTeX:
@article{asner_condition_2006, author = {Asner, Gr.P. and Broadbent, E.N. and Oliveira, P. J. C. and Keller, M. and Knapp, D. E. and Silva, J. N. M.}, title = {Condition and fate of logged forests in the Brazilian Amazon}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2006}, volume = {103}, number = {34}, pages = {12947--12950}, note = {Edition: 2006/08/12}, url = {://WOS:000240035900054 http://www.pnas.org/content/103/34/12947.full.pdf}, doi = {https://doi.org/10.1073/pnas.0604093103} } |
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Asner, G.P. and Alencar, A. | Drought impacts on the Amazon forest: the remote sensing perspective | 2010 | New Phytologist Vol. 187(3), pp. 569-578 |
article | DOI URL |
Abstract: PtextgreaterDrought varies spatially and temporally throughout the Amazon basin, challenging efforts to assess ecological impacts via field measurements alone. Remote sensing offers a range of regional insights into drought-mediated changes in cloud cover and rainfall, canopy physiology, and fire. Here, we summarize remote sensing studies of Amazonia which indicate that: fires and burn scars are more common during drought years; hydrological function including floodplain area is significantly affected by drought; and land use affects the sensitivity of the forest to dry conditions and increases fire susceptibility during drought. We highlight two controversial areas of research centering on canopy physiological responses to drought and changes in subcanopy fires during drought. By comparing findings from field and satellite studies, we contend that current remote sensing observations and techniques cannot resolve these controversies using current satellite observations. We conclude that studies integrating multiple lines of evidence from physiological, disturbance-fire, and hydrological remote sensing, as well as field measurements, are critically needed to narrow our uncertainty of basin-level responses to drought and climate change. | |||||
BibTeX:
@article{asner_drought_2010, author = {Asner, Gregory P. and Alencar, Ane}, title = {Drought impacts on the Amazon forest: the remote sensing perspective}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {569--578}, note = {Edition: 2010/06/08}, url = {://WOS:000280122500006 http://onlinelibrary.wiley.com/store/10.1111/j.1469-8137.2010.03310.x/asset/j.1469-8137.2010.03310.x.pdf?v=1&t=h6hxc10c&s=b2761b08b0c1cc2f4364510177d361f9a35278aa}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03310.x} } |
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Asner, G.P. | Cloud cover in Landsat observations of the Brazilian Amazon | 2001 | International Journal of Remote Sensing Vol. 22(18), pp. 3855-3862 |
article | DOI URL |
Abstract: High spatial resolution Landsat imagery is employed in efforts to understand the impact of human activities on ecological, biogeochemical and atmospheric processes in the Amazon basin. The utility of Landsat multi-spectral data depends both on the degree to which surface properties can be estimated from the radiometric measurements and on the ability to observe the surface through the atmosphere. Clouds are a major obstacle to optical remote sensing of humid tropical regions, therefore cloud cover probability analysis is a fundamental prerequisite to land-cover change and Earth system process studies in these regions. This paper reports the results of a spatially explicit analysis of cloud cover in the Landsat archive of Brazilian Amazonia from 1984 to 1997. Monthly observations of any part of the basin are highly improbable using Landsat-like optical imagers. Annual observations are possible for most of the basin, but are improbable in northern parts of the region. These results quantify the limitations imposed by cloud cover to current Amazon land-cover change assessments using Landsat data. They emphasize the need for improved radar and alternative optical data fusion techniques to provide time-series analyses of biogeophysical properties for regional modelling efforts. | |||||
BibTeX:
@article{asner_cloud_2001, author = {Asner, G. P.}, title = {Cloud cover in Landsat observations of the Brazilian Amazon}, journal = {International Journal of Remote Sensing}, year = {2001}, volume = {22}, number = {18}, pages = {3855--3862}, url = {://WOS:000172088800015 http://www.tandfonline.com/doi/abs/10.1080/01431160010006926}, doi = {https://doi.org/10.1080/01431160010006926} } |
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Artaxo, P., Silva Dias, M., Nagy, L., Luizão, F., Cunha, H., Quesada, C., Marengo, J. and Krusche, A. | Perspectivas de pesquisas na relação entre clima e o funcionamento da floresta amazônica [BibTeX] |
2014 | Ciência & Cultura Vol. 66(3), pp. 41-46 |
article | |
BibTeX:
@article{artaxo_perspectivas_2014, author = {Artaxo, P. and Silva Dias, M.A.F.S. and Nagy, L. and Luizão, F.L. and Cunha, H.B. and Quesada, C.A.N. and Marengo, J.A. and Krusche, A.}, title = {Perspectivas de pesquisas na relação entre clima e o funcionamento da floresta amazônica}, journal = {Ciência & Cultura}, year = {2014}, volume = {66}, number = {3}, pages = {41--46} } |
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Artaxo, P., Rizzo, L.V., Paixão, M., Lucca, S.d., Oliveira, P.H., Lara, L.L., Wiedemann, K.T., Andreae, M.O., Holben, B., Schafer, J., Correia, A.L. and Pauliquevis, T.M. | Aerosol Particles in Amazonia: Their Composition, Role in the Radiation Balance, Cloud Formation, and Nutrient Cycles [BibTeX] |
2009 | Vol. 1(Geophysical Monograph 186)Amazonia and Global Change, pp. 233-250 |
incollection | |
BibTeX:
@incollection{m_keller_aerosol_2009, author = {Artaxo, Paulo and Rizzo, Luciana V. and Paixão, Melina and Lucca, Silvia de and Oliveira, Paulo H. and Lara, Luciene L. and Wiedemann, Kenia T. and Andreae, Meinrat O. and Holben, Brent and Schafer, Joel and Correia, Alexandre L. and Pauliquevis, Theotônio M.}, title = {Aerosol Particles in Amazonia: Their Composition, Role in the Radiation Balance, Cloud Formation, and Nutrient Cycles}, booktitle = {Amazonia and Global Change}, publisher = {American Geophysical Union}, year = {2009}, volume = {1}, number = {Geophysical Monograph 186}, pages = {233--250} } |
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Artaxo, P., Rizzo, L.V., Brito, J.F., Barbosa, H.M.J., Arana, A., Sena, E.T., Cirino, G.G., Bastos, W., Martin, S.T. and Andreae, M.O. | Atmospheric aerosols in Amazonia and land use change: from natural biogenic to biomass burning conditions [BibTeX] |
2013 | Faraday Discussions Vol. 165, pp. 203-235 |
article | DOI |
BibTeX:
@article{artaxo_atmospheric_2013, author = {Artaxo, P. and Rizzo, L. V. and Brito, J. F. and Barbosa, H. M. J. and Arana, A. and Sena, E. T. and Cirino, G. G. and Bastos, W. and Martin, S. T. and Andreae, M. O.}, title = {Atmospheric aerosols in Amazonia and land use change: from natural biogenic to biomass burning conditions}, journal = {Faraday Discussions}, year = {2013}, volume = {165}, pages = {203--235}, doi = {https://doi.org/10.1039/C3FD00052D} } |
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Artaxo, P., Martins, J.V., Yamasoe, M.A., Procopio, A.S., Pauliquevis, T.M., Andreae, M.O., Guyon, P., Gatti, L.V. and Leal, A.M.C. | Physical and chemical properties of aerosols in the wet and dry seasons in Rondonia, Amazonia | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20), pp. 8081 - 8095 |
article | DOI URL |
Abstract: As part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), a large study of aerosol and trace gas properties was conducted in Amazonia during the dry and wet seasons and for pasture and primary forest sites. Aerosol mass and elemental composition were measured on filters for both fine (d(p) textless2.0 mu m) and coarse (2.0 textless d(p) textless10 m m) modes using polycarbonate filters mounted in stacked filter units (SFU). Measurements with real-time aerosol and trace gas monitors were made, parallel to the collection of filter samples to obtain high time resolution (1-30 min). Black carbon equivalent (BCE) was determined with a multiwavelength Aethalometer as well as by reflectance in the fine-mode SFU samples. Elemental carbon as well as total and organic carbon was measured using an R&P 5400 real-time carbon monitor. PM(10) aerosol mass concentrations were determined with a Tapered Element Oscillating Monitor (TEOM) monitor every 5 min. CO, O(3), NO, and NO(2) were analyzed with Thermo Environment monitors with trace level capabilities for NO(x). A TSI 3010 particle counter measured the total particle number concentration (d(p) textgreater 10 nm) every minute. A 55-m tower in a primary forest in Rondonia and a facility built on a pasture site were used to operate the instrumentation for 4 months in the wet season and 3 months in the dry season of 1999. Particle-Induced X-Ray Emission (PIXE) was used to measure the concentration of 22 trace elements for fine- and coarse-mode aerosol. During the wet season, very clean atmospheric conditions were observed at both sites. Particle concentration averaged 900 cm 3, black carbon averaged 250 ng m(-3), and mean fine- mode mass concentration was 2.9 mug m(-3). In sharp contrast, very high concentrations were observed in the dry season for all the parameters at both sampling sites. Aerosol mass concentrations up to 250 mug m 3 and particle number concentrations of more than 40,000 cm(-3) were observed, while the CO peaked at 8 ppm and NO(2) reached 16 ppb. High correlation was observed between BCE, NO(2), CO, aerosol particle number, mass, aerosol optical thickness, and other properties linked to biomass-burning emissions. Relatively large concentrations of phosphorus in the coarse-mode particles were observed, especially at nighttime. The emission of biogenic particulate P could have an effect in the nutrient cycling of this essential and key nutrient, which is present almost exclusively in the form of aerosol particles. Phosphorus is exchanged in the aerosol phase and mostly for coarse-mode particles and during nighttime. | |||||
BibTeX:
@article{artaxo_physical_2002, author = {Artaxo, P. and Martins, J. V. and Yamasoe, M. A. and Procopio, A. S. and Pauliquevis, T. M. and Andreae, M. O. and Guyon, P. and Gatti, L. V. and Leal, A. M. C.}, title = {Physical and chemical properties of aerosols in the wet and dry seasons in Rondonia, Amazonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, pages = {8081 -- 8095}, url = {://WOS:000180466200053 http://www.agu.org/journals/jd/jd0219/2001JD000666/2001JD000666.pdf}, doi = {https://doi.org/10.1029/2001jd000666} } |
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Artaxo, P., Hansson, H.-C., Andreae, M., Bäck, J., Alves, E., Barbosa, H., Bender, F., Bourtsoukidis, E., Carbone, S., Chi, J., Decesari, S., Despres, V., Ditas, F., Ezhova, E., Sandro, F., Hasselquist, N., Heintzenberg, J., Holanda, B., Guenther, A. and Makshtas, A. | Tropical and Boreal Forest – Atmosphere Interactions: A Review [BibTeX] |
3 | Tellus B Vol. 74, pp. 24-163 |
article | DOI |
BibTeX:
@article{artaxo_tropical_3, author = {Artaxo, Paulo and Hansson, Hans-Christen and Andreae, Meinrat and Bäck, Jaana and Alves, Eliane and Barbosa, Henrique and Bender, Frida and Bourtsoukidis, Efstratios and Carbone, S. and Chi, Jinshu and Decesari, Stefano and Despres, Viviane and Ditas, Florian and Ezhova, Ekaterina and Sandro, Fuzzi and Hasselquist, Niles and Heintzenberg, Jost and Holanda, Bruna and Guenther, Alex and Makshtas, A.}, title = {Tropical and Boreal Forest – Atmosphere Interactions: A Review}, journal = {Tellus B}, year = {3}, volume = {74}, pages = {24--163}, doi = {https://doi.org/10.16993/tellusb.34} } |
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Artaxo, P., Forsberg, B.R. and Nagy, L. | Amazonia in Perspective as a Changing Environment [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 465-469 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_amazonia_2016, author = {Artaxo, Paulo and Forsberg, Bruce R. and Nagy, Laszlo}, title = {Amazonia in Perspective as a Changing Environment}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {465--469}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Artaxo, P., de Campos, R.C., Fernandes, E.T., Martins, J.V., Xiao, Z.F., Lindqvist, O., Fernandez-Jimenez, M.T. and Maenhaut, W. | Large scale mercury and trace element measurements in the Amazon basin | 2000 | Atmospheric Environment Vol. 34(24), pp. 4085-4096 |
article | DOI URL |
Abstract: Large emissions of mercury (Hg) occur in the Amazon Basin as a result of gold mining activities. Mercury and aerosol particles were collected in the Amazon basin, as part of the SCAR-B-Smoke Clouds and Radiation - Brazil experiment in August and September 1995. Three airplanes were used to collect total mercury and aerosol particles. Sampling was performed with the University of Washington Lockheed C131A airplane, as well as in two Brazilian Bandeirante EMB 120 planes. Atmospheric mercury was sampled using two gold traps in series for each sampling line and measured with atomic fluorescence spectrometer (AFS). Aerosols were collected on Teflon and polycarbonate filters and analyzed by particle-induced X-ray emission (PIXE) for up to 20 elements, and by instrumental neutron activation analysis (INAA) for up to 39 elements. Absorbing aerosols expressed as black carbon (BC), and aerosol gravimetric mass were also determined. Sampling time was 2-4 h. The sampling period was at the peak of the biomass burning season, when most of the Hg is emitted. Concentrations for total Hg in this study were as high as 14.8 ng m(-3). Factor analysis was performed for the combined (aerosol and Hg) data set and six factors were observed: A soil dust component; a biomass-burning factor (with fine mode mass concentration, BC, K, Cl, Zn and others); a natural biogenic component (P, K, S, Ca, Mn, Zn); a second soil dust factor (enriched in Si); a sea-salt aerosol component, with NaCl; and a factor related to gold mining activities, with Hg, Pb and other elements. Hg was also clearly associated with the biomass-burning component, in addition to the gold mining activities component. An average of 63% of the Hg concentrations was associated with the gold mining activities. About 31% of the Hg concentration was associated with the biomass-burning component, the soil dust accounted for 4% and the NaCl component for 2.1% of the airborne Hg concentrations. The high association between Hg and biomass burning can be caused by at least three mechanisms: (1) adsorption of gaseous Hg on existing biomass burning particles; (2) direct release of Hg from the vegetation to the atmosphere during forest burning; (3) evaporation of Hg from soil during the forest burning. Three-dimensional long-range air mass trajectory analyses show the possibility that Hg exits the Amazon Basin over two main routes: to the South Atlantic, and to the Tropical Pacific, over the Andes. (C) 2000 Elsevier Science Ltd. All rights reserved. | |||||
BibTeX:
@article{artaxo_large_2000, author = {Artaxo, P. and de Campos, R. C. and Fernandes, E. T. and Martins, J. V. and Xiao, Z. F. and Lindqvist, O. and Fernandez-Jimenez, M. T. and Maenhaut, W.}, title = {Large scale mercury and trace element measurements in the Amazon basin}, journal = {Atmospheric Environment}, year = {2000}, volume = {34}, number = {24}, pages = {4085--4096}, url = {://WOS:000088818200004 http://ac.els-cdn.com/S1352231000001060/1-s2.0-S1352231000001060-main.pdf?_tid=f6e43408-03f1-11e2-a639-00000aacb361&acdnat=1348235033_104bd9aa434c250901a427692883ef2d}, doi = {https://doi.org/10.1016/s1352-2310(00)00106-0} } |
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Artaxo, P. and Coutinho, S. | Complexidade científica das mudanças climáticas e os acordos internacionais [BibTeX] |
2015 | Temas atuais em mudanças climáticas: para os ensinos fundamental e médio, pp. 7-11 | incollection | |
BibTeX:
@incollection{pedro_roberto_jacobi_complexidade_2015, author = {Artaxo, P. and Coutinho, S.M.V.}, title = {Complexidade científica das mudanças climáticas e os acordos internacionais}, booktitle = {Temas atuais em mudanças climáticas: para os ensinos fundamental e médio}, publisher = {IEE - USP}, year = {2015}, pages = {7--11} } |
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Artaxo, P. | Working together for Amazonia [BibTeX] |
2019 | Science Vol. 363, pp. 323-323 |
article | |
BibTeX:
@article{artaxo_working_2019, author = {Artaxo, P.}, title = {Working together for Amazonia}, journal = {Science}, year = {2019}, volume = {363}, pages = {323--323} } |
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Artaxo, P. | Break down boundaries in climate research [BibTeX] |
2012 | Nature Vol. 481(7381), pp. 239 |
article | DOI URL |
BibTeX:
@article{artaxo_break_2012, author = {Artaxo, P.}, title = {Break down boundaries in climate research}, journal = {Nature}, year = {2012}, volume = {481}, number = {7381}, pages = {239}, note = {Edition: 2012/01/20}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22258570}, doi = {https://doi.org/10.1038/481239a} } |
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Artaxo, P. | Riscos e desafios: O aquecimento global não é o fim [BibTeX] |
2011 | Mudanças climáticas e mudanças socioambientais globais: reflexões sobre alternativas de futuro, pp. 184pp. | incollection | |
BibTeX:
@incollection{unescoibecc_riscos_2011, author = {Artaxo, P.}, title = {Riscos e desafios: O aquecimento global não é o fim}, booktitle = {Mudanças climáticas e mudanças socioambientais globais: reflexões sobre alternativas de futuro}, publisher = {Coordenação de Eda Terezinha de Oliveira e Emília Wanda Rutkowiski.}, year = {2011}, pages = {184pp.}, note = {Section: Pag. 11-14.} } |
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Artaxo, P. | O papel dos aerossóis no sistema climático [BibTeX] |
2011 | O futuro da Terra, pp. 312 | incollection | |
BibTeX:
@incollection{moyses_nussenzveig_o_2011, author = {Artaxo, P.}, title = {O papel dos aerossóis no sistema climático}, booktitle = {O futuro da Terra}, year = {2011}, pages = {312}, note = {Section: 167-194} } |
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Artaxo, O., Lara, P.H., Pauliquevis, L.L., Rizzo, T.M., Junior, LV., Paixão, C.P., Longo, M.A., Freitas, K.M., Correia, S. and P, A.L. | Efeitos climáticos de partículas de aerossóis biogênicos e emitidos em queimadas na Amazônia [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3a), pp. 168-189 |
article | |
BibTeX:
@article{artaxo_efeitos_2006, author = {Artaxo, Oliveira, P.H., Lara, L.L., Pauliquevis, T.M., Rizzo, LV., Junior, C.P., Paixão, M.A., Longo, K.M., Freitas, S., Correia, A.L., P}, title = {Efeitos climáticos de partículas de aerossóis biogênicos e emitidos em queimadas na Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3a}, pages = {168--189} } |
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Artaxo, G., Leal, L.V., A.M.C., L., Freitas, K.M., Lara, S.R., Pauliquevis, L.L., Procópio, T.M., Rizzo, A.S. and P., L.V. | Química atmosférica na Amazônia: A Floresta e as emissões de queimadas controlando a composição da atmosfera amazônica. [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 185-196 |
article | |
BibTeX:
@article{artaxo_quimica_2005, author = {Artaxo, Gatti, L.V., Leal, A.M.C., Longo, K.M., Freitas, S.R., Lara, L.L., Pauliquevis, T.M., Procópio, A.S., Rizzo, L.V., P.}, title = {Química atmosférica na Amazônia: A Floresta e as emissões de queimadas controlando a composição da atmosfera amazônica.}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {185--196} } |
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Arruda, .P.H.Z.D., Vourlitis, .G.L., Santanna, .F.B., Pinto Jr., .O.B., Lobo, .F.d.A. and Nogueira, J.d.S. | Large net CO2 loss from a grass-dominated tropical savanna in south-central Brazil in response to seasonal and interannual drought [BibTeX] |
2016 | JGR | article | DOI |
BibTeX:
@article{arruda_large_2016, author = {Arruda, Paulo Henrique Zanella De and Vourlitis, George Louis and Santanna, Franciele Bomfiglio and Pinto Jr., Osvaldo Borges and Lobo, Francisco de Almeida and Nogueira, José de Souza}, title = {Large net CO2 loss from a grass-dominated tropical savanna in south-central Brazil in response to seasonal and interannual drought}, journal = {JGR}, year = {2016}, doi = {https://doi.org/10.1002/2016JG003404} } |
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Arruda, J., Filho, A., Nogueira, N.P., Almeida Filho, J.S., Campelo Júnior, E.O., Vourlitis, J.H. and J.C., G.L. | Aplicação de três metodologias para estimar o fluxo de calor latente em floresta de transição [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3b), pp. 233-240 |
article | |
BibTeX:
@article{arruda_aplicacao_2006, author = {Arruda, Jorge, A., Filho, N.P., Nogueira, J.S., Almeida Filho, E.O., Campelo Júnior, J.H., Vourlitis, G.L., J.C.}, title = {Aplicação de três metodologias para estimar o fluxo de calor latente em floresta de transição}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3b}, pages = {233--240} } |
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Arima, E., Walker, R., Sales, M.H., Souza Jr., C. and Perz, S.G. | The fragmentation of space in the Amazon basin: Emergent road networks | 2008 | Photogrammetric Engineering and Remote Sensing Vol. 74(6), pp. 699-709 |
article | URL |
Abstract: In this article, we simulate forest fragmentation patterns by reference to the actual decision-making of the agents engaged in the fragmentation process itself. We take as our empirical case fragmentation in the Brazilian Amazon basin associated with road-building by loggers. Roads built by the private sector, particularly loggers, play a decisive role in the dynamics of frontier expansion in the Amazon. Our objective is to explain the manner in which logging roads manifest spatially, thereby creating fragmented landscapes in a small portion of the so-called "Terra do Meio," a region of 300,000 km(2) in the heart of the Amazon basin. We combine geostatistical methods with GIS to replicate a common fragmentation pattern found in tropical forests known as dendritic. Such fragmentation has been identified as one of the three most common types observed in the Amazon basin. The model replicates the general dendritic pattern and many branching points of the network, although segments do not overlay precisely. The paper concludes with a discussion of steps necessary to develop a model that is fully effective in describing the spatial decision-making of loggers. | |||||
BibTeX:
@article{arima_fragmentation_2008, author = {Arima, E.Y. and Walker, R.T. and Sales, M. H. and Souza, Jr., Carlos and Perz, S. G.}, title = {The fragmentation of space in the Amazon basin: Emergent road networks}, journal = {Photogrammetric Engineering and Remote Sensing}, year = {2008}, volume = {74}, number = {6}, pages = {699--709}, url = {://WOS:000256695900004} } |
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Arima, E.Y., Walker, R.T., Perz, S.G. and Caldas, M. | Loggers and forest fragmentation: Behavioral models of road building in the Amazon basin | 2005 | Annals of the Association of American Geographers Vol. 95(3), pp. 525-541 |
article | DOI URL |
Abstract: Although a large literature now exists on the drivers of tropical deforestation, less is known about its spatial manifestation. This is a critical shortcoming in our knowledge base since the spatial pattern of land-cover change and forest fragmentation, in particular, strongly affect biodiversity. The purpose of this article is to consider emergent patterns of road networks, the initial proximate cause of fragmentation in tropical forest frontiers. Specifically, we address the road-building processes of loggers who are very active in the Amazon landscape. To this end, we develop an explanation of road expansions, using a positive approach combining a theoretical model of economic behavior with geographic information systems (GIS) software in order to mimic the spatial decisions of road builders. We simulate two types of road extensions commonly found in the Amazon basin in a region showing the fishbone pattern of fragmentation. Although our simulation results are only partially successful, they call attention to the role of multiple agents in the landscape, the importance of legal and institutional constraints on economic behavior, and the power of GIS as a research tool. | |||||
BibTeX:
@article{arima_loggers_2005, author = {Arima, E. Y. and Walker, R. T. and Perz, S. G. and Caldas, M.}, title = {Loggers and forest fragmentation: Behavioral models of road building in the Amazon basin}, journal = {Annals of the Association of American Geographers}, year = {2005}, volume = {95}, number = {3}, pages = {525--541}, url = {://WOS:000231225400003 http://www.tandfonline.com/doi/abs/10.1111/j.1467-8306.2005.00473.x}, doi = {https://doi.org/10.1111/j.1467-8306.2005.00473.x} } |
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Arima, E.Y., Simmons, C.S., Walker, R.T. and Cochrane, M.A. | Fire in the Brazilian amazon: A spatially explicit model for policy impact analysis | 2007 | Journal of Regional Science Vol. 47(3), pp. 541-567 |
article | DOI URL |
Abstract: This article implements a spatially explicit model to estimate the probability of forest and agricultural fires in the Brazilian Amazon. We innovate by using variables that reflect farm-gate prices of beef and soy, and also provide a conceptual model of field management and deforestation fires to simulate the impact of road-paving, cattle exports, and conservation area designation on the occurrence of fire. Our analysis shows that fire is positively correlated with the price of beef and soy, and that the creation of new conservation units may offset the negative environmental impacts caused by the increasing number of fire events associated with early stages of frontier development. | |||||
BibTeX:
@article{arima_fire_2007, author = {Arima, Eugenio Y. and Simmons, Cynthia S. and Walker, Robert T. and Cochrane, Mark A.}, title = {Fire in the Brazilian amazon: A spatially explicit model for policy impact analysis}, journal = {Journal of Regional Science}, year = {2007}, volume = {47}, number = {3}, pages = {541--567}, url = {://WOS:000248150500005 http://onlinelibrary.wiley.com/store/10.1111/j.1467-9787.2007.00519.x/asset/j.1467-9787.2007.00519.x.pdf?v=1&t=h6hxb9c2&s=982b53148cc41da399965f37ed34490541bbf5bb}, doi = {https://doi.org/10.1111/j.1467-9787.2007.00519.x} } |
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Arima, E.Y., Richards, P., Walker, R. and Caldas, M.M. | Statistical confirmation of indirect land use change in the Brazilian Amazon | 2011 | Environmental Research Letters Vol. 6(2) |
article | DOI URL |
Abstract: Expansion of global demand for soy products and biofuel poses threats to food security and the environment. One environmental impact that has raised serious concerns is loss of Amazonian forest through indirect land use change (ILUC), whereby mechanized agriculture encroaches on existing pastures, displacing them to the frontier. This phenomenon has been hypothesized by many researchers and projected on the basis of simulation for the Amazonian forests of Brazil. It has not yet been measured statistically, owing to conceptual difficulties in linking distal land cover drivers to the point of impact. The present article overcomes this impasse with a spatial regression model capable of linking the expansion of mechanized agriculture in settled agricultural areas to pasture conversions on distant, forest frontiers. In an application for a recent period (2003-2008), the model demonstrates that ILUC is significant and of considerable magnitude. Specifically, a 10% reduction of soy in old pasture areas would have decreased deforestation by as much as 40% in heavily forested counties of the Brazilian Amazon. Evidently, the voluntary moratorium on primary forest conversions by Brazilian soy farmers has failed to stop the deforestation effects of expanding soy production. Thus, environmental policy in Brazil must pay attention to ILUC, which can complicate efforts to achieve its REDD targets. | |||||
BibTeX:
@article{arima_statistical_2011, author = {Arima, Eugenio Y. and Richards, Peter and Walker, Robert and Caldas, Marcellus M.}, title = {Statistical confirmation of indirect land use change in the Brazilian Amazon}, journal = {Environmental Research Letters}, year = {2011}, volume = {6}, number = {2}, url = {://WOS:000295326800010 http://iopscience.iop.org/1748-9326/6/2/024010/pdf/1748-9326_6_2_024010.pdf}, doi = {https://doi.org/10.1088/1748-9326/6/2/024010} } |
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Arieira, J., Karssenberg, D., de Jong, S.M., Addink, E.A., Couto, E.G., Nunes da Cunha, C. and Skøien, J.O. | Integrating field sampling, geostatistics and remote sensing to map wetland vegetation in the Pantanal, Brazil | 2011 | Biogeosciences Vol. 8(3), pp. 667-686 |
article | DOI URL |
Abstract: Development of efficient methodologies for mapping wetland vegetation is of key importance to wetland conservation. Here we propose the integration of a number of statistical techniques, in particular cluster analysis, universal kriging and error propagation modelling, to integrate observations from remote sensing and field sampling for mapping vegetation communities and estimating uncertainty. The approach results in seven vegetation communities with a known floral composition that can be mapped over large areas using remotely sensed data. The relationship between remotely sensed data and vegetation patterns, captured in four factorial axes, were described using multiple linear regression models. There were then used in a universal kriging procedure to reduce the mapping uncertainty. Cross-validation procedures and Monte Carlo simulations were used to quantify the uncertainty in the resulting map. Cross-validation showed that accuracy in classification varies according with the community type, as a result of sampling density and configuration. A map of uncertainty derived from Monte Carlo simulations revealed significant spatial variation in classification, but this had little impact on the proportion and arrangement of the communities observed. These results suggested that mapping improvement could be achieved by increasing the number of field observations of those communities with a scattered and small patch size distribution; or by including a larger number of digital images as explanatory variables in the model. Comparison of the resulting plant community map with a flood duration map, revealed that flooding duration is an important driver of vegetation zonation. This mapping approach is able to integrate field point data and high-resolution remote-sensing images, providing a new basis to map wetland vegetation and allow its future application in habitat management, conservation assessment and long-term ecological monitoring in wetland landscapes. | |||||
BibTeX:
@article{arieira_integrating_2011, author = {Arieira, J. and Karssenberg, D. and de Jong, S. M. and Addink, E. A. and Couto, E. G. and Nunes da Cunha, C. and Skøien, J. O.}, title = {Integrating field sampling, geostatistics and remote sensing to map wetland vegetation in the Pantanal, Brazil}, journal = {Biogeosciences}, year = {2011}, volume = {8}, number = {3}, pages = {667--686}, url = {://000288911300010 http://www.biogeosciences.net/8/667/2011/bg-8-667-2011.pdf}, doi = {https://doi.org/10.5194/bg-8-667-2011} } |
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Araujo-Murakami, A., Doughty, C.E., Metcalfe, D.B., Silva-Espejo, J.E., Arroyo, L., Heredia, J.P., Flores, M., Sibler, R., Mendizabal, L.M., Pardo-Toledo, E., Vega, M., Moreno, L., Rojas-Landivar, V.D., Halladay, K., Girardin, C.A., Killeen, T.J. and Malhi, Y. | The productivity, allocation and cycling of carbon in forests at the dry margin of the Amazon forest in Bolivia [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 55-69 |
article | |
BibTeX:
@article{araujo-murakami_productivity_2014, author = {Araujo-Murakami, Alejandro and Doughty, Christopher E. and Metcalfe, Daniel B. and Silva-Espejo, Javier E. and Arroyo, Luzmila and Heredia, Juan P. and Flores, Marcio and Sibler, Rebeca and Mendizabal, Luz M. and Pardo-Toledo, Erwin and Vega, Meison and Moreno, Luzmarina and Rojas-Landivar, Victor D. and Halladay, Kate and Girardin, Cecile A.J. and Killeen, Timothy J. and Malhi, Yadvinder}, title = {The productivity, allocation and cycling of carbon in forests at the dry margin of the Amazon forest in Bolivia}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {55--69} } |
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Araujo, Y., Luizao, F.J. and Barros, E. | Effect of earthworm addition on soil nitrogen availability, microbial biomass and litter decomposition in mesocosms | 2004 | Biology and Fertility of Soils Vol. 39(3), pp. 146-152 |
article | DOI URL |
Abstract: The aim of the study was to determine the effect of adding two tropical earthworm species, Rhinodrilus contortus and Pontoscolex corethrurus, to mesocosms on the availability of mineral N (NH4+ and NO(3)(-)concentrations), soil microbial biomass (bio-N), and the decomposition rates of three contrasting leaf litter species, in a glasshouse experiment. The mesocosms were filled with forest soil and covered with a layer of leaf litter differing in nutritional quality: (1) Hevea brasiliensis (C/N=27); (2) Carapa guianensis (C/N=32); (3) Vismia sp., the dominant tree species in the second growth forest (control, C/N= 42); and, (4) a mixture of the former three leaf species, in equal proportions (C/N=34). At the end of the 97-day experiment, the soil mineral N concentrations, bio-N, and leaf litter weight loss were determined. Both earthworm species showed significant effects on the concentrations of soil NO3-(ptextless0.01) and NH4+ (ptextless0.05). Bio-N was always greater in the mesocosms with earthworms (especially with R. contortus) and in the mesocosms with leaf litter of H. brasiliensis (6 mug N g(-1) soil), the faster decomposing species, than in the other treatments (0.1-1.6 mug N g(-1)). Thus, earthworm activity increased soil mineral-N concentrations, possibly due to the consumption of soil microbial biomass, which can speed turnover and mineralization of microbial tissues. No significant differences in decomposition rate were found between the mesocosms with and without earthworms, suggesting that experiments lasting longer are needed to determine the effect of earthworms on litter decomposition rates. | |||||
BibTeX:
@article{araujo_effect_2004, author = {Araujo, Y. and Luizao, F. J. and Barros, E.}, title = {Effect of earthworm addition on soil nitrogen availability, microbial biomass and litter decomposition in mesocosms}, journal = {Biology and Fertility of Soils}, year = {2004}, volume = {39}, number = {3}, pages = {146--152}, url = {://WOS:000189001700003 http://www.springerlink.com/content/efuh7rcdgvtg07am/fulltext.pdf}, doi = {https://doi.org/10.1007/s00374-003-0696-0} } |
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Araujo, R.F., Nelson, B.W., Celes, C.H.S. and Chambers, J.Q. | Regional distribution of large blowdown patche sacross Amazonia in 2005 caused by a single convective squall line [BibTeX] |
2017 | Geophys. Res. Lett. Vol. 44, pp. 7793-7798 |
article | |
BibTeX:
@article{araujo_regional_2017, author = {Araujo, R. F. and Nelson, B. W. and Celes, C. H. S. and Chambers, J. Q.}, title = {Regional distribution of large blowdown patche sacross Amazonia in 2005 caused by a single convective squall line}, journal = {Geophys. Res. Lett.}, year = {2017}, volume = {44}, pages = {7793--7798} } |
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Araújo, R., Castro, E., Rocha, G., Sá, M.E., Mathis, A., Monteiro, M., Puty, C., Monteiro, R., Canto, O. and Bennatti, J. | Estado e Sociedade na BR163: desmatamento, conflitos e processos de ordenamento territorial [BibTeX] |
2008 | Vol. 1Sociedade, Território e Conflitos: BR-163 em questão |
incollection | |
BibTeX:
@incollection{castro_estado_2008, author = {Araújo, R. and Castro, E. and Rocha, G. and Sá, M. E. and Mathis, A. and Monteiro, M. and Puty, C. and Monteiro, R. and Canto, O. and Bennatti, J.}, title = {Estado e Sociedade na BR163: desmatamento, conflitos e processos de ordenamento territorial}, booktitle = {Sociedade, Território e Conflitos: BR-163 em questão}, publisher = {NAEA / UFPA}, year = {2008}, volume = {1}, note = {Section: 13-84} } |
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Araujo, A.C.d., Kruijt, B., Nobre, A.D., Dolman, A.J., Waterloo, M.J., Moors, E.J. and de Souza, J.S. | Nocturnal accumulation of CO(2) underneath a tropical forest canopy along a topographical gradient | 2008 | Ecological Applications Vol. 18(6), pp. 1406-1419 |
article | URL |
Abstract: Flux measurements of carbon dioxide and water vapor above tropical rain forests are often difficult to interpret because the terrain is usually complex. This complexity induces heterogeneity in the surface but also affects lateral movement of carbon dioxide (CO(2)) not readily detected by the eddy covariance systems. This study describes such variability using measurements of CO(2) along vertical profiles and along a toposequence in a tropical rain forest near Manaus, Brazil. Seasonal and diurnal variation was recorded, with atmospheric CO(2) concentration maxima around dawn, generally higher CO(2) build-up in the dry season and stronger daytime CO(2) drawdown in the wet season. This variation was reflected all along the toposequence, but the slope and valley bottom accumulated clearly more CO(2) than the plateaus, depending on atmospheric stability. Particularly during stable nights, accumulation was along lines of equal altitude, suggesting that large amounts of CO(2) are stored in the valleys of the landscape. Flushing of this store only occurs during mid-morning, when stored CO(2) may well be partly transported back to the plateaus. It is clear that, for proper interpretation of tower fluxes in such complex and actively respiring terrain, the horizontal variability of storage needs to be taken into account not only during the night but also during the mornings. | |||||
BibTeX:
@article{araujo_nocturnal_2008, author = {Araujo, Alessandro C. de and Kruijt, Bart and Nobre, Antonio D. and Dolman, Albertus J. and Waterloo, Maarten J. and Moors, Eddy J. and de Souza, Juliana S.}, title = {Nocturnal accumulation of CO(2) underneath a tropical forest canopy along a topographical gradient}, journal = {Ecological Applications}, year = {2008}, volume = {18}, number = {6}, pages = {1406--1419}, url = {://WOS:000258413600009} } |
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Araújo, A.C.d., Dolman, A.J., Waterloo, M.J., Gash, J.H.C., Kruijt, B., Zanchi, F.B., de Lange, J.M.E., Stoevelaar, R., Manzi, A.O. and Nobre, A.D. | The spatial variability of CO2 storage and the interpretation of eddy covariance fluxes in central Amazonia | 2010 | Agricultural and Forest Meteorology Vol. 150(2), pp. 226-237 |
article | DOI URL |
Abstract: The landscape of central Amazonia is composed of plateaus and valleys. Previous observations have shown preferential pooling of CO(2) in the valleys, suggesting that the change in CO(2) storage in the canopy air space (S) will be spatially variable at the scale of the topography. This may affect the interpretation of the net ecosystem CO(2) exchange (NEE) rates measured on the plateaus if they have used one single atmospheric CO(2) concentration ([CO(2)]) vertical profile measurement system. We have measured the diel, spatial and seasonal variation of S along the topography by using a set of automated [CO(2)] vertical profile measurement systems. In addition, NEE, the above-canopy turbulent exchange of CO(2) (F(C)) and meteorological variables were also measured on a micrometeorological tower located on the plateau. The nocturnal accumulation of CO(2) was larger on the slopes and in the valleys than on the plateau and was larger in the dry period than in the wet period. In addition, the release of this CO(2) occurred later in the day on the slopes and in the valleys than on the plateau. Differences in the flow regime above the canopy along the topographical gradient, lateral drainage of respired CO(2) downslope, and temporal, spatial, and seasonal variation of soil CO(2) efflux (R(soil)) are thought to have contributed to this. These conditions cause S to be higher in magnitude on the slopes and in the valleys than on the plateau during midmorning hours. We demonstrate that there is a larger underestimation of R(eco) by nighttime eddy covariance (EC) measurements in the dry period than in the wet period. In addition, R(eco) - as derived from measurements only on the plateau (F(C) + S(P)) - does not agree with that derived by an independent method. Yet S fluxes peaked at about 18:00-20:00 on the slopes and in the valleys, following a continuous decrease after this period until reaching a minimum just after dawn. NEE derived from F(C) measured on the plateau and S measured on the plateau, slope and valley increased the estimates of R(eco) on the plateau by about 30% and 70% in the wet and dry periods, respectively. Particularly for flux-tower sites over complex terrain, we recommend measuring the spatial variability of CO(2) at, at least two, more points along the topography to determine to what extent horizontal gradients and storage changes may contribute to tower fluxes. Finally, for sites that present topographical characteristics similar to that described in this study, care must be taken with the use of single in-canopy profiles of [CO(2)] to correct EC fluxes. (C) 2009 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{araujo_spatial_2010, author = {Araújo, A. C. de and Dolman, A. J. and Waterloo, M. J. and Gash, J. H. C. and Kruijt, B. and Zanchi, F. B. and de Lange, J. M. E. and Stoevelaar, R. and Manzi, A. O. and Nobre, A. D.}, title = {The spatial variability of CO2 storage and the interpretation of eddy covariance fluxes in central Amazonia}, journal = {Agricultural and Forest Meteorology}, year = {2010}, volume = {150}, number = {2}, pages = {226--237}, url = {://WOS:000274871800010 http://ac.els-cdn.com/S0168192309002706/1-s2.0-S0168192309002706-main.pdf?_tid=eb3f1e56-03f1-11e2-8da7-00000aab0f27&acdnat=1348235014_912ce2e8ff5e6b483508d45f1226355c}, doi = {https://doi.org/10.1016/j.agrformet.2009.11.005} } |
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Araújo, A.C., Randow, C.v. and Restrepo-Coupe, N. | Ecosystem-Atmosphere Exchanges of CO2 in Dense and Open ‘Terra Firme’ Rainforests in Brazilian Amazonia [BibTeX] |
2016 | Vol. Ecological Studies(Analysis and Synthesis 227)Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin, pp. 149-169 |
incollection | DOI |
BibTeX:
@incollection{nagy_lazlo_ecosystem-atmosphere_2016, author = {Araújo, Alessandro C. and Randow, Celso von and Restrepo-Coupe, Natalia}, title = {Ecosystem-Atmosphere Exchanges of CO2 in Dense and Open ‘Terra Firme’ Rainforests in Brazilian Amazonia}, booktitle = {Interactions between Biosphere, Atmosphere and Human Land Use in the Amazon Basin}, publisher = {Springer Verlag}, year = {2016}, volume = {Ecological Studies}, number = {Analysis and Synthesis 227}, pages = {149--169}, doi = {https://doi.org/10.1007/978-3-662-49902-3} } |
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Araujo, A.C., Ometto, J.P.H.B., Dolman, A.J., Kruijt, B., Waterloo, M.J. and Ehleringer, J.R. | Implications of CO(2) pooling on delta(13)C of ecosystem respiration and leaves in Amazonian forest | 2008 | Biogeosciences Vol. 5(3), pp. 779-795 |
article | URL |
Abstract: The carbon isotope of a leaf (delta(13)C(leaf)) is generally more negative in riparian zones than in areas with low soil moisture content or rainfall input. In Central Amazonia, the small-scale topography is composed of plateaus and valleys, with plateaus generally having a lower soil moisture status than the valley edges in the dry season. Yet in the dry season, the nocturnal accumulation of CO(2) is higher in the valleys than on the plateaus. Samples of sunlit leaves and atmospheric air were collected along a topographical gradient in the dry season to test whether the delta(13)C(leaf) of sunlit leaves and the carbon isotope ratio of ecosystem respired CO(2) (delta(13)C(Reco)) may be more negative in the valley than those on the plateau. The delta(13)C(leaf) was significantly more negative in the valley than on the plateau. Factors considered to be driving the observed variability in delta(13)C(leaf) were: leaf nitrogen concentration, leaf mass per unit area (LMA), soil moisture availability, more negative carbon isotope ratio of atmospheric CO(2) (delta(13)C(a)) in the valleys during daytime hours, and leaf discrimination (Delta(leaf)). The observed pattern of delta(13)C(leaf) might suggest that water-use efficiency (WUE) is higher on the plateaus than in the valleys. However, there was no full supporting evidence for this because it remains unclear how much of the difference in delta(13)C(leaf) was driven by physiology or delta(13)C(a). The delta(13)C(Reco) was more negative in the valleys than on the plateaus on some nights, whereas in others it was not. It is likely that lateral drainage of CO(2) enriched in (13)C from upslope areas might have happened when the nights were less stable. Biotic factors such as soil CO(2) efflux (R(soil)) and the responses of plants to environmental variables such as vapor pressure deficit ( D) may also play a role. The preferential pooling of CO(2) in the low-lying areas of this landscape may confound the interpretation of delta(13)C(leaf) and delta(13)C(Reco). | |||||
BibTeX:
@article{araujo_implications_2008, author = {Araujo, A. C. and Ometto, J. P. H. B. and Dolman, A. J. and Kruijt, B. and Waterloo, M. J. and Ehleringer, J. R.}, title = {Implications of CO(2) pooling on delta(13)C of ecosystem respiration and leaves in Amazonian forest}, journal = {Biogeosciences}, year = {2008}, volume = {5}, number = {3}, pages = {779--795}, url = {://WOS:000257303400012} } |
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Araujo, A.C., Nobre, A.D., Kruijt, B., Elbers, J.A., Dallarosa, R., Stefani, P., von Randow, C., Manzi, A.O., Culf, A.D., Gash, J.H.C., Valentini, R. and Kabat, P. | Comparative measurements of carbon dioxide fluxes from two nearby towers in a central Amazonian rainforest: The Manaus LBA site | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Forests around Manaus have staged the oldest and the longest forest-atmosphere CO2 exchange studies made anywhere in the Amazon. Since July 1999 the exchange of CO2, water, and energy, as well as weather variables, have been measured almost continuously over two forests, 11 km apart, in the Cuieiras reserve near Manaus, Brazil. This paper presents the sites and climatology of the region based upon the new data sets. The landscape consists of plateaus dissected by often waterlogged valleys, and the two sites differ in terms of the relative areas of those two landscape components represented in the tower footprints. The radiation and wind climate was similar to both towers. Generally, both the long-wave and short-wave radiation input was less in the wet than in the dry season. The energy balance closure was imperfect (on average 80%) in both towers, with little variation in energy partitioning between the wet and dry seasons; likely a result of anomalously high rainfall in the 1999 dry season. Fluxes of CO2 also showed little seasonal variation except for a slightly shorter daytime uptake duration and somewhat lower respiratory fluxes in the dry season. The net effect is one of lower daily net ecosystem exchange (NEE) in the dry season. The tower, which has less waterlogged valley areas in its footprint, measured a higher overall CO2 uptake rate. We found that on first sight, NEE is underestimated during calm nights, as was observed in many other tower sites before. However, a closer inspection of the diurnal variation of CO2 storage fluxes and NEE suggests that at least part of the nighttime deficits is recovered from either lateral influx of CO2 from valleys or outgassing of soil storage. Therefore there is a high uncertainty in the magnitude of nocturnal NEE, and consequently preliminary estimates of annual carbon uptake reflecting this range from 1 to 8 T ha(-1) y(-1), with an even higher upper range for the less waterlogged area. The high uptake rates are clearly unsustainable and call for further investigations into the integral carbon balance of Amazon landscapes. | |||||
BibTeX:
@article{araujo_comparative_2002, author = {Araujo, A. C. and Nobre, A. D. and Kruijt, B. and Elbers, J. A. and Dallarosa, R. and Stefani, P. and von Randow, C. and Manzi, A. O. and Culf, A. D. and Gash, J. H. C. and Valentini, R. and Kabat, P.}, title = {Comparative measurements of carbon dioxide fluxes from two nearby towers in a central Amazonian rainforest: The Manaus LBA site}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200112 http://www.agu.org/journals/jd/jd0220/2001JD000676/2001JD000676.pdf}, doi = {https://doi.org/10.1029/2001jd000676} } |
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Arana, A., Loureiro, A.L., Barbosa, H.M.J., Van Grieken, R. and Artaxo, P. | Optimized energy dispersive X-ray fluorescence analysis of atmospheric aerosols collected at pristine and perturbed Amazon Basin sites [BibTeX] |
2014 | X-Ray Spectrom, pp. 10p | article | DOI |
BibTeX:
@article{arana_optimized_2014, author = {Arana, A. and Loureiro, A. L. and Barbosa, H. M. J. and Van Grieken, R. and Artaxo, P.}, title = {Optimized energy dispersive X-ray fluorescence analysis of atmospheric aerosols collected at pristine and perturbed Amazon Basin sites}, journal = {X-Ray Spectrom}, year = {2014}, pages = {10p}, doi = {https://doi.org/10.1002/xrs.2544} } |
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Arana, A. and Artaxo, P. | Composição elementar do aerossol atmosférico na região central da bacia amazônica [BibTeX] |
2014 | Quimica Nova Vol. 37(2), pp. 268-276 |
article | DOI |
BibTeX:
@article{arana_composicao_2014, author = {Arana, A. and Artaxo, P.}, title = {Composição elementar do aerossol atmosférico na região central da bacia amazônica}, journal = {Quimica Nova}, year = {2014}, volume = {37}, number = {2}, pages = {268--276}, doi = {https://doi.org/10.5935/0100-4042.20140046} } |
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Aragao, L., Shimabukuro, Y.E., Santo, F. and Williams, M. | Landscape pattern and spatial variability of leaf area index in Eastern Amazonia | 2005 | Forest Ecology and Management Vol. 211(3), pp. 240-256 |
article | DOI URL |
Abstract: Uncertainties about the implications of land-cover heterogeneity on the Amazonian carbon (C) and water cycles are, in part, related to the lack of information about spatial patterns of key variables that control these fluxes at the regional scale. Leaf area index (LAI) is one of these key variables, regulating a number of ecosystem processes (e.g. evaporation, transpiration and photosynthesis). In order to generate a sampling strategy for LAI across a section of Amazonia, we generated a landscape unit (LU) map for the Tapajos region, Eastern Amazonia, as a basis for stratification. We identified seven primary forest classes, stratified according to vegetation and/or terrain characteristics, and one secondary forest class, covering 80% of the region. Primary forest units were the most representative, covering 62% of the total area. The LAI measurements were carried out in 13 selected LUs. In each LU, we marked out three 50 m x 50 m plots giving a total number of 39 plots (9.75 ha). A pair of LAI-2000 plant canopy analysers was used to estimate LAI. We recorded a total of 25 LAI measurements within each plot. We used the field data to verify the statistical distribution of LAI samples, analyse the LAI variability within and among sites, and show the influence of sample size on LAI variation and precision. The LAI showed a high coefficient of variation at the plot level (0.25 ha), from 5.2% to 23%, but this was reduced at the landscape unit level (three co-located plots, 1.8-12%). The level of precision was textless 10% and 15% at the plot and landscape unit level, respectively. The LAI decreased from a dense lowland forest site (5.10) to a secondary forest (3.46) and to a pasture site (1.56). We found evidence for differences in the scale of spatial heterogeneity of closed canopy forest versus open canopy forest and palm forests. Landscape variables could, in part, explain differences in LAI among forest sites, and land use is an important modifier of LAI patterns. The stratified LAI sampling proposed in the present study could cope with three important aspects of C and water fluxes modelling: (1) optimise the information obtained from field measurements, which is an advance for models parameterisation, compared to the usual random sampling; (2) generate information for a subsequent scaling up of point field | |||||
BibTeX:
@article{aragao_landscape_2005, author = {Aragao, L.E.O.C. and Shimabukuro, Y. E. and Santo, Fdbe and Williams, M.}, title = {Landscape pattern and spatial variability of leaf area index in Eastern Amazonia}, journal = {Forest Ecology and Management}, year = {2005}, volume = {211}, number = {3}, pages = {240--256}, url = {://WOS:000229876000002 http://ac.els-cdn.com/S0378112705001088/1-s2.0-S0378112705001088-main.pdf?_tid=e6ff1cc4-03f1-11e2-8dd3-00000aab0f02&acdnat=1348235007_83a80c094db5e1bbffd03ecdcb6ce686}, doi = {https://doi.org/10.1016/j.foreco.2005.02.062} } |
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Aragao, L., Shimabukuro, Y.E., Espirito-Santo, F.D.B. and Williams, M. | Spatial validation of the collection 4 MODIS LAI product in eastern amazonia (vol 43,pg 2526, 2005) [BibTeX] |
2005 | Ieee Transactions on Geoscience and Remote Sensing Vol. 43(12), pp. 2973-2973 |
article | URL |
BibTeX:
@article{aragao_spatial_2005, author = {Aragao, L.E.O.C. and Shimabukuro, Y. E. and Espirito-Santo, F. D. B. and Williams, M.}, title = {Spatial validation of the collection 4 MODIS LAI product in eastern amazonia (vol 43,pg 2526, 2005)}, journal = {Ieee Transactions on Geoscience and Remote Sensing}, year = {2005}, volume = {43}, number = {12}, pages = {2973--2973}, url = {://WOS:000233479000029} } |
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Aragao, L.E.O.C., Malhi, Y., Roman-Cuesta, R.M., Saatchi, S., Anderson, L.O. and Shimabukuro, Y.E. | Spatial patterns and fire response of recent Amazonian droughts | 2007 | Geophysical Research Letters Vol. 34(7) |
article | DOI URL |
Abstract: There has been an increasing awareness of the possibility of climate change causing increased drought frequency in Amazonia, with ensuing impacts on ecosystems and human populations. This debate has been brought into focus by the 1997/1998 and 2005 Amazonian droughts. We analysed the spatial extent of these droughts and fire response to the 2005 drought with TRMM and NOAA-12 data, respectively. Both droughts had distinct fingerprints. The 2005 drought was characterized by its intensification throughout the dry season in south-western Amazonia. During 2005 the annual cumulative number of hot pixels in Amazonia increased 33% in relation to the 1999 - 2005 mean. In the Brazilian state of Acre, at the epicentre of the 2005 drought, the area of leakage forest fires was more than five times greater than the area directly deforested. Fire leakage into flammable forests may be the major agent of biome transformation in the event of increasing drought frequency. | |||||
BibTeX:
@article{aragao_spatial_2007, author = {Aragao, Luiz Eduardo O. C. and Malhi, Yadvinder and Roman-Cuesta, Rosa Maria and Saatchi, Sassan and Anderson, Liana O. and Shimabukuro, Yosio Edemir}, title = {Spatial patterns and fire response of recent Amazonian droughts}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {7}, url = {://WOS:000245578300004 http://www.agu.org/pubs/crossref/2007/2006GL028946.shtml}, doi = {https://doi.org/10.1029/2006gl028946} } |
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Aragao, L.E.O.C., Malhi, Y., Metcalfe, D.B., Silva-Espejo, J.E., Jimenez, E., Navarrete, D., Almeida, S., Costa, A.C.L., Salinas, N., Phillips, O.L., Anderson, L.O., Alvarez, E., Baker, T.R., Goncalvez, P.H., Huaman-Ovalle, J., Mamani-Solorzano, M., Meir, P., Monteagudo, A., Patino, S., Penuela, M.C., Prieto, A., Quesada, C.A., Rozas-Davila, A., Rudas, A., Silva Jr., J.A. and Vasquez, R. | Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils | 2009 | Biogeosciences Vol. 6(12), pp. 2759-2778 |
article | URL |
Abstract: The net primary productivity (NPP) of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and below-ground components and the main environmental drivers of these patterns. In this study we quantify the above- and below-ground NPP of ten Amazonian forests to address two questions: (1) How do Amazonian forests allocate productivity among its above- and below-ground components? (2) How do soil and leaf nutrient status and soil texture affect the productivity of Amazonian forests? Using a standardized methodology to measure the major elements of productivity, we show that NPP varies between 9.3 +/- 1.3 Mg C ha(-1) yr(-1) (mean +/- standard error), at a white sand plot, and 17.0 +/- 1.4 Mg C ha(-1) yr(-1) at a very fertile Terra Preta site, with an overall average of 12.8 +/- 0.9 Mg C ha(-1) yr(-1). The studied forests allocate on average 64 +/- 3% and 36 +/- 3% of the total NPP to the above- and below-ground components, respectively. The ratio of above-ground and below-ground NPP is almost invariant with total NPP. Litterfall and fine root production both increase with total NPP, while stem production shows no overall trend. Total NPP tends to increase with soil phosphorus and leaf nitrogen status. However, allocation of NPP to below-ground shows no relationship to soil fertility, but appears to decrease with the increase of soil clay content. | |||||
BibTeX:
@article{aragao_above-_2009, author = {Aragao, L. E. O. C. and Malhi, Y. and Metcalfe, D. B. and Silva-Espejo, J. E. and Jimenez, E. and Navarrete, D. and Almeida, S. and Costa, A. C. L. and Salinas, N. and Phillips, O. L. and Anderson, L. O. and Alvarez, E. and Baker, T. R. and Goncalvez, P. H. and Huaman-Ovalle, J. and Mamani-Solorzano, M. and Meir, P. and Monteagudo, A. and Patino, S. and Penuela, M. C. and Prieto, A. and Quesada, C. A. and Rozas-Davila, A. and Rudas, A. and Silva, Jr., J. A. and Vasquez, R.}, title = {Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {12}, pages = {2759--2778}, url = {://WOS:000273060100003} } |
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Aragao, L.C., Malhi, Y., Barbier, N., Lima, A., Shimabukuro, Y., Anderson, L.O. and Saatchi, S. | Interactions between rainfall, deforestation and fires during recent years in the Brazilian Amazonia | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1779-1785 |
article | DOI URL |
Abstract: Understanding the interplay between climate and land-use dynamics is a fundamental concern for assessing the vulnerability of Amazonia to climate change. In this study, we analyse satellite-derived monthly and annual time series of rainfall, fires and deforestation to explicitly quantify the seasonal patterns and relationships between these three variables, with a particular focus on the Amazonian drought of 2005. Our results demonstrate a marked seasonality with one peak per year for all variables analysed, except deforestation. For the annual cycle, we found correlations above 90% with a time lag between variables. Deforestation and fires reach the highest values three and six months, respectively, after the peak of the rainy season. The cumulative number of hot pixels was linearly related to the size of the area deforested annually from 1998 to 2004 (r2=0.84, p=0.004). During the 2005 drought, the number of hot pixels increased 43% in relation to the expected value for a similar deforested area (approx. 19000km2). We demonstrated that anthropogenic forcing, such as land-use change, is decisive in determining the seasonality and annual patterns of fire occurrence. Moreover, droughts can significantly increase the number of fires in the region even with decreased deforestation rates. We may expect that the ongoing deforestation, currently based on slash and burn procedures, and the use of fires for land management in Amazonia will intensify the impact of droughts associated with natural climate variability or human-induced climate change and, therefore, a large area of forest edge will be under increased risk of fires. | |||||
BibTeX:
@article{aragao_interactions_2008, author = {Aragao, L.E.O. C. and Malhi, Y. and Barbier, N. and Lima, A. and Shimabukuro, Y. and Anderson, L. O. and Saatchi, S.}, title = {Interactions between rainfall, deforestation and fires during recent years in the Brazilian Amazonia}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1779--1785}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500009 http://rstb.royalsocietypublishing.org/content/363/1498/1779.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0026} } |
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Aragão, L.E.O.C., Anderson, L.O., Fonseca, M.G., Rosan, T.M., Vedovato, L.B., Wagner, F.H., Silva, C.V.J., Silva Junior, C.H.L., Arai, E., Aguiar, A.P., Barlow, J., Berenguer, E., Deeter, M.N., Domingues, L.G., Gatti, L., Gloor, M., Malhi, Y., Marengo, J.A., Miller, J.B., Phillips, O.L. and Saatchi, S. | 21st Century drought-related fires counteract the decline of Amazon deforestation carbon emissions [BibTeX] |
2018 | Nature Communications Vol. 9, pp. 1-12 |
article | |
BibTeX:
@article{aragao_21st_2018, author = {Aragão, Luiz E. O. C. and Anderson, L. O. and Fonseca, M. G. and Rosan, T. M. and Vedovato, Laura B. and Wagner, Fabien H. and Silva, Camila V. J. and Silva Junior, Celso H. L. and Arai, E. and Aguiar, A. P. and Barlow, J. and Berenguer, E. and Deeter, Merritt N. and Domingues, L. G. and Gatti, L. and Gloor, M. and Malhi, Y. and Marengo, J. A. and Miller, J. B. and Phillips, O. L. and Saatchi, S.}, title = {21st Century drought-related fires counteract the decline of Amazon deforestation carbon emissions}, journal = {Nature Communications}, year = {2018}, volume = {9}, pages = {1--12} } |
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Aragão, L., Poulter, B., Barlow, J., Anderson, L., Malhi, Y., Saatchi, S., Phillips, O. and Gloor, E. | Environmental change and the carbon balance of Amazonian forests. [BibTeX] |
2014 | Biological Reviews Vol. 89(4), pp. 913-931 |
article | DOI |
BibTeX:
@article{aragao_environmental_2014, author = {Aragão, LEOC. and Poulter, B. and Barlow, JB. and Anderson, LO. and Malhi, Y. and Saatchi, S. and Phillips, OL. and Gloor, E.}, title = {Environmental change and the carbon balance of Amazonian forests.}, journal = {Biological Reviews}, year = {2014}, volume = {89}, number = {4}, pages = {913--931}, doi = {https://doi.org/10.1111/brv.12088} } |
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Aquino, M., Marques Júnior, J., Oliveira, I., Mantovanelli, B., Soares M.D.R., R. and Campos | Geoestatística na avaliação dos atributos físicos em latossolo sob floresta nativa e pastagem na Região de Manicoré, Amazonas [BibTeX] |
2014 | Revista Brasileira de Ciência do Solo Vol. 38, pp. 397-406 |
article | |
BibTeX:
@article{aquino_geoestatistica_2014, author = {Aquino, M.C.C.; Marques Júnior, J.; Oliveira, I.A.; Mantovanelli, B.C.; Soares, M.D.R., R.E.; Campos}, title = {Geoestatística na avaliação dos atributos físicos em latossolo sob floresta nativa e pastagem na Região de Manicoré, Amazonas}, journal = {Revista Brasileira de Ciência do Solo}, year = {2014}, volume = {38}, pages = {397--406} } |
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Aquino, M., Oliveira I.A., R. and Campos | Atributos Físicos do Solo em Áreas de Terra Preta Arqueológica na Região Amazônica [BibTeX] |
2013 | Vol. 1(1ed.)Atributos Físicos do Solo em Áreas de Terra Preta Arqueológica na Região Amazônica., pp. 90-106 |
incollection | |
BibTeX:
@incollection{org_atributos_2013, author = {Aquino, M.C.C.; Oliveira, I.A., R.E.; Campos}, title = {Atributos Físicos do Solo em Áreas de Terra Preta Arqueológica na Região Amazônica}, booktitle = {Atributos Físicos do Solo em Áreas de Terra Preta Arqueológica na Região Amazônica.}, publisher = {FUNEP}, year = {2013}, volume = {1}, number = {1ed.}, pages = {90--106}, note = {Section: 1} } |
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Aquino, R., Campos, M., Marques Junior, J., Oliveira, I., Teixeira, D. and Cunha, J. | Use of scaled semivariograms in the planning sample of soil physical properties in southern amazonas, Brazil [BibTeX] |
2015 | Revista Brasileira de Ciência do Solo Vol. 39, pp. 21-30 |
article | |
BibTeX:
@article{aquino_use_2015, author = {Aquino, R.E and Campos, M.C.C. and Marques Junior, J. and Oliveira, I.A. and Teixeira, D.B. and Cunha, J.M.}, title = {Use of scaled semivariograms in the planning sample of soil physical properties in southern amazonas, Brazil}, journal = {Revista Brasileira de Ciência do Solo}, year = {2015}, volume = {39}, pages = {21--30} } |
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Antonucci, B., Camatta Barbino, G., Reis de Andrade, N.L. and Dresch Webler, A. | Efeito de um evento de friagem no cenário de mudança no uso e cobertura da terra no Sudoeste da Amazônia | 7 | Revista Brasileira de Climatologia Vol. 33(19), pp. 149 - 168 |
article | DOI URL |
Abstract: <p>A conversão de florestas altera o microclima. A entrada de massas polares ocorre na América do Sul, no entanto, na Amazônia o efeito é diferente, com quedas da temperatura no inverno e chuvas de convecção no verão. Diante disso, caracterizou a friagem em áreas com coberturas de floresta, pastagem e cidade na região central do estado de Rondônia, bem como, entender a atuação dos fenômenos em cada cobertura. Foram utilizados dados das torres micrometeorológicas do Programa de Grande Escala da Biosfera-Atmosfera na Amazônia na cidade acima de um prédio, e os dados da floresta e pastagem foram coletados em torre com alturas de 62m e 08m, respectivamente. No ano de 2017 foi identificado a entrada de um evento de friagem nos quais a redução média de 31% na temperatura mínima ocorreu para as 03 coberturas. Como característica da massa polar, a umidade especifica nas localidades reduziu na passagem dos eventos, no entanto, somente na floresta ocorreu chuva com características frontais. Notou-se uma duplicação no valor da velocidade do vento e predominância do vento Sul. Após a passagem da friagem, o reestabelecimento da temperatura média ocorreu em 03 dias. De maneira geral, as condições micrometeorológicas locais são alteradas pela entrada da massa de ar fria e seca, sendo que os impactos são mais intensos nas áreas antropizadas. No entanto, são necessários mais estudos para avaliar a influência da cobertura do solo nessa resposta e possíveis impactos na vida da população.</p> | |||||
BibTeX:
@article{antonucci_efeito_7, author = {Antonucci, Bárbara and Camatta Barbino, Gutieres and Reis de Andrade, Nara Luísa and Dresch Webler, Alberto}, title = {Efeito de um evento de friagem no cenário de mudança no uso e cobertura da terra no Sudoeste da Amazônia}, journal = {Revista Brasileira de Climatologia}, year = {7}, volume = {33}, number = {19}, pages = {149 -- 168}, note = {Section: Artigos}, url = {https://ojs.ufgd.edu.br/index.php/rbclima/article/view/16675}, doi = {https://doi.org/10.55761/abclima.v33i19.16675} } |
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Antonucci, B., AGuiar, R., Aguiar, L.J.G. and Andrade, N.L.R. | Fluxos de CO2 em uma Área de Floresta Tropical Úmida na Amazônia Ocidental em um Ano de El Niño [BibTeX] |
2018 | Ciência e Natura Vol. 40, pp. 119-125 |
article | |
BibTeX:
@article{antonucci_fluxos_2018, author = {Antonucci, B. and AGuiar, R.G.. and Aguiar, L. J. G. and Andrade, N. L. R.}, title = {Fluxos de CO2 em uma Área de Floresta Tropical Úmida na Amazônia Ocidental em um Ano de El Niño}, journal = {Ciência e Natura}, year = {2018}, volume = {40}, pages = {119--125} } |
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Ansmann, A., Baars, H., Tesche, M., Mueller, D., Althausen, D., Engelmann, R., Pauliquevis, T. and Artaxo, P. | Dust and smoke transport from Africa to South America: Lidar profiling over Cape Verde and the Amazon rainforest | 2009 | Geophysical Research Letters Vol. 36 |
article | DOI URL |
Abstract: Quasi-simultaneous vertically resolved multiwavelength aerosol Raman lidar observations were conducted in the near field (Praia, Cape Verde, 15 degrees N, 23.5 degrees W) and in the far field (Manaus, Amazon basin, Brazil, 2.5 degrees S, 60 degrees W) of the long-range transport regime between West Africa and South America. Based on a unique data set (case study) of spectrally resolved backscatter and extinction coefficients, and of the depolarization ratio a detailed characterization of aerosol properties, vertical stratification, mixing, and aging behavior during the long-distance travel in February 2008 (dry season in western Africa, wet season in the Amazon basin) is presented. While highly stratified aerosol layers of dust and smoke up to 5.5 km height were found close to Africa, the aerosol over Manaus was almost well-mixed, reached up to 3.5 km, and mainly consisted of aged biomass burning smoke. Citation: Ansmann, A., H. Baars, M. Tesche, D. Muller, D. Althausen, R. Engelmann, T. Pauliquevis, and P. Artaxo (2009), Dust and smoke transport from Africa to South America: Lidar profiling over Cape Verde and the Amazon rainforest, Geophys. Res. Lett., 36, L11802, doi: 10.1029/2009GL037923. | |||||
BibTeX:
@article{ansmann_dust_2009, author = {Ansmann, Albert and Baars, Holger and Tesche, Matthias and Mueller, Detlef and Althausen, Dietrich and Engelmann, Ronny and Pauliquevis, Theotonio and Artaxo, Paulo}, title = {Dust and smoke transport from Africa to South America: Lidar profiling over Cape Verde and the Amazon rainforest}, journal = {Geophysical Research Letters}, year = {2009}, volume = {36}, url = {://WOS:000266741500001 http://www.agu.org/pubs/crossref/2009/2009GL037923.shtml}, doi = {https://doi.org/10.1029/2009gl037923} } |
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Anhuf, D., Ledru, M.P., Behling, H., Da Cruz Jr., F.W., Cordeiro, R.C., Van der Hammen, T., Karmann, I., Marengo, J.A., De Oliveira, P.E., Pessenda, L., Siffedine, A., Albuquerque, A.L. and Dias, P.L.D.S. | Paleo-environmental change in Amazonian and African rainforest during the LGM | 2006 | Palaeogeography Palaeoclimatology Palaeoecology Vol. 239(3-4), pp. 510-527 |
article | DOI URL |
Abstract: The paper provides new and comparative insight into the ecological history of the two largest continental tropical forest areas during the Last Glacial Maximum (LGM). The tropical forest regions are of particular interest because they present a large source of heat and have been shown to have significant impact on the extra tropical atmospheric circulation. They are also the most intense land-based convective centers. Thus, especially from the tropics paleoecological information is needed as benchmarks for climate modeling. The African data for LGM climates were published earlier including the reconstructed paleoprecipitation patterns deduced from SSTs. The tropical South American LGM data were interpreted from pollen, geochemical, and delta O-18 (stable oxygen isotope) data from Brazil and selected surrounding areas. The available terrestrial data are consistent with the SST derived precipitation data for the tropical forests in Brazil and for Africa. However, the impact of LGM climate extremes was less severe in the Amazon than in the Congo basin. The LGM humid forest area (including evergreen and semi-deciduous forest types) in Africa was probably reduced by 84%. In contrast, the Amazon humid forest area probably shrank to 54% of their present-day extension. Still, there are different interpretations with respect to the amount of reduction of the Amazon forest area during the LGM. Although direct information about LGM climates in Amazonia is still limited the more detailed map obtained in the present work, however, allows a more reliable characterization of the last glacial tropical environment than previously published for the Amazon region. (c) 2006 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{anhuf_paleo-environmental_2006, author = {Anhuf, D. and Ledru, M. P. and Behling, H. and Da Cruz, Jr., F. W. and Cordeiro, R. C. and Van der Hammen, T. and Karmann, I. and Marengo, J. A. and De Oliveira, P. E. and Pessenda, L. and Siffedine, A. and Albuquerque, A. L. and Dias, P. L. Da Silva}, title = {Paleo-environmental change in Amazonian and African rainforest during the LGM}, journal = {Palaeogeography Palaeoclimatology Palaeoecology}, year = {2006}, volume = {239}, number = {3-4}, pages = {510--527}, url = {://WOS:000241047200015 http://ac.els-cdn.com/S0031018206000472/1-s2.0-S0031018206000472-main.pdf?_tid=dcbdd6e2-03f1-11e2-8733-00000aacb35d&acdnat=1348234991_ad9d07e3ec19025ef94793a23a572258}, doi = {https://doi.org/10.1016/j.palaeo.2006.01.017} } |
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Angelini, I.M., Garstang, M., Davis, R.E., Hayden, B., Fitzjarrald, D.R., Legates, D.R., Greco, S., Macko, S. and Connors, V. | On the coupling between vegetation and the atmosphere | 2011 | Theoretical and Applied Climatology Vol. 105(1-2), pp. 243-261 |
article | DOI URL |
Abstract: Recent studies suggest that vegetation can drive large-scale atmospheric circulations and substantially influence the hydrologic cycle. We present observational evidence to quantify the extent of coupling between vegetation and the overlying atmosphere. Within the context of vegetation-atmospheric interactions, we reanalyze existing climatological data from springtime leaf emergence, emissivity, dew point temperatures, and historical records of precipitation and forest coverage. We construct new rainfall transects based on a robust global climatology. Using isotopic analysis of precipitation, we find that rain in Amazonia comes primarily from large-scale weather systems coupling interior regions to the ocean and is not directly driven by local evaporation. We find that changes in vegetative cover and state influence the temperature and moisture content of the surface and atmospheric boundary layer but are not reflected in observable precipitation changes. This analysis reaffirms the view that changes in precipitation over continental reaches are a product of complex processes only partly influenced but not controlled by local water sources or vegetation. | |||||
BibTeX:
@article{angelini_coupling_2011, author = {Angelini, Isabella M. and Garstang, Michael and Davis, Robert E. and Hayden, Bruce and Fitzjarrald, David R. and Legates, David R. and Greco, Steven and Macko, Stephen and Connors, Vickie}, title = {On the coupling between vegetation and the atmosphere}, journal = {Theoretical and Applied Climatology}, year = {2011}, volume = {105}, number = {1-2}, pages = {243--261}, url = {://WOS:000293021500021 http://www.springerlink.com/content/k6p30u320r3786j7/fulltext.pdf}, doi = {https://doi.org/10.1007/s00704-010-0377-5} } |
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Andrews, A.E., Kofler, J.D., Trudeau, M.E., Williams, J.C., Neff, D.H., Masarie, K.A., Chao, D.Y., Kitzis, D.R., Novelli, P.C., Zhao, C.L., Dlugokencky, E.J., Lang, P.M., Crotwell, M.J., Fischer, M.L., Parker, M.J., Lee, J.T., Baumann, D.D., Desai, A.R., Stanier, C.O., De Wekker, S.F.J., Wolfe, D.E., Munger, J.W. and Tans, P.P. | CO2, CO, and CH4 measurements from tall towers in the NOAA Earth System Research Laboratory's Global Greenhouse Gas Reference Network: instrumentation, uncertainty analysis, and recommendations for future high-accuracy greenhouse gas monitoring efforts [BibTeX] |
2014 | Atmos. Meas. Tech. Vol. 7(2), pp. 647-687 |
article | DOI URL |
BibTeX:
@article{andrews_co2_2014, author = {Andrews, A. E. and Kofler, J. D. and Trudeau, M. E. and Williams, J. C. and Neff, D. H. and Masarie, K. A. and Chao, D. Y. and Kitzis, D. R. and Novelli, P. C. and Zhao, C. L. and Dlugokencky, E. J. and Lang, P. M. and Crotwell, M. J. and Fischer, M. L. and Parker, M. J. and Lee, J. T. and Baumann, D. D. and Desai, A. R. and Stanier, C. O. and De Wekker, S. F. J. and Wolfe, D. E. and Munger, J. W. and Tans, P. P.}, title = {CO2, CO, and CH4 measurements from tall towers in the NOAA Earth System Research Laboratory's Global Greenhouse Gas Reference Network: instrumentation, uncertainty analysis, and recommendations for future high-accuracy greenhouse gas monitoring efforts}, journal = {Atmos. Meas. Tech.}, year = {2014}, volume = {7}, number = {2}, pages = {647--687}, url = {https://amt.copernicus.org/articles/7/647/2014/}, doi = {https://doi.org/10.5194/amt-7-647-2014} } |
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Andreoli, R., Kayano, M., Candido L.A., R. and Souza | Seasonal anomalous rainfall in the central and eastern Amazon and associated anomalous oceanic and atmospheric patterns [BibTeX] |
2012 | International Journal of Climatology Vol. 32, pp. 1193-1205 |
article | |
BibTeX:
@article{andreoli_seasonal_2012, author = {Andreoli, R.A.F.; Kayano, M.T.; Candido, L.A., R.V.; Souza}, title = {Seasonal anomalous rainfall in the central and eastern Amazon and associated anomalous oceanic and atmospheric patterns}, journal = {International Journal of Climatology}, year = {2012}, volume = {32}, pages = {1193--1205} } |
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Andreae, M.O., Rosenfeld, D., Artaxo, P., Costa, A.A., Frank, G.P., Longo, K.M. and Silva-Dias, M.A.F. | Smoking rain clouds over the Amazon | 2004 | Science Vol. 303(5662), pp. 1337-1342 |
article | DOI URL |
Abstract: Heavy smoke from forest. res in the Amazon was observed to reduce cloud droplet size and so delay the onset of precipitation from 1.5 kilometers above cloud base in pristine clouds to more than 5 kilometers in polluted clouds and more than 7 kilometers in pyro-clouds. Suppression of low-level rainout and aerosol washout allows transport of water and smoke to upper levels, where the clouds appear "smoking" as they detrain much of the pollution. Elevating the onset of precipitation allows invigoration of the updrafts, causing intense thunderstorms, large hail, and greater likelihood for overshooting cloud tops into the stratosphere. There, detrained pollutants and water vapor would have profound radiative impacts on the climate system. The invigorated storms release the latent heat higher in the atmosphere. This should substantially affect the regional and global circulation systems. Together, these processes affect the water cycle, the pollution burden of the atmosphere, and the dynamics of atmospheric circulation. | |||||
BibTeX:
@article{andreae_smoking_2004, author = {Andreae, M. O. and Rosenfeld, D. and Artaxo, P. and Costa, A. A. and Frank, G. P. and Longo, K. M. and Silva-Dias, M. A. F.}, title = {Smoking rain clouds over the Amazon}, journal = {Science}, year = {2004}, volume = {303}, number = {5662}, pages = {1337--1342}, note = {Edition: 2004/02/28}, url = {://WOS:000189238600042 http://www.sciencemag.org/content/303/5662/1337}, doi = {https://doi.org/10.1126/science.1092779} } |
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Andreae, M.O. and Rosenfeld, D. | Aerosol-cloud-precipitation interactions. Part 1. The nature and sources of cloud-active aerosols | 2008 | Earth-Science Reviews Vol. 89(1-2), pp. 13-41 |
article | DOI URL |
Abstract: Atmospheric aerosol particles serve as condensation nuclei for the formation of both, cloud droplets and atmospheric ice particles. As a result, they exert a substantial influence on the microphysical properties of water and ice clouds, which in turn affect the processes that lead to the formation of rain, snow, hail, and other forms of precipitation. In recent years, considerable progress has been made in understanding the chemical composition of aerosols, their microphysical properties, and the factors that enable them to act as cloud condensation nuclei (CCN) and ice nuclei (IN). The first part of this review article will focus on the nature and sources of CCN and IN. We discuss the fundamentals of the cloud droplet and ice nucleation processes, and the role that the chemical composition and particle size play in this process. We show that, in many instances, the influence of chemical composition can be represented by a simple parameterization, which leaves particle size as the main variable controlling CCN efficiency. Aerosol particles are produced either directly by anthropogenic and natural sources (dust, sea salt, soot, biological particles, etc.), or they are formed in the atmosphere by condensation of low-volatility compounds (e.g., sulfuric acid or oxidized organic compounds). We discuss the magnitude of these sources, and the CCN and IN characteristics of the particles they produce. In contrast to previous assessments, which focused on the aerosol mass, we are emphasizing the number of particles being produced, as this is the key variable in cloud microphysics. Large uncertainties still exist for many aerosol sources, e.g., the submicron part of the seaspray aerosol, the particles produced by the biosphere, and the secondary organic aerosol. We conclude with a discussion on what particle concentrations may have been in the pristine atmosphere, before the onset on anthropogenic pollution. Model calculations and observations in remote continental regions consistently suggest that CCN concentrations over the pristine continents were similar to those now prevailing over the remote oceans, suggesting that human activities have modified cloud microphysics more than what is reflected in conventional wisdom. The second part of this review will address the effects of changing CCN and IN abundances on precipitation processes, the water cycle, and climate. (C) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{andreae_aerosol-cloud-precipitation_2008, author = {Andreae, M. O. and Rosenfeld, D.}, title = {Aerosol-cloud-precipitation interactions. Part 1. The nature and sources of cloud-active aerosols}, journal = {Earth-Science Reviews}, year = {2008}, volume = {89}, number = {1-2}, pages = {13--41}, url = {://WOS:000257534400002 http://ac.els-cdn.com/S0012825208000317/1-s2.0-S0012825208000317-main.pdf?_tid=d49fcfb0-03f1-11e2-9816-00000aacb35e&acdnat=1348234976_53361d59ada8bcbc299c83ef142a1f13}, doi = {https://doi.org/10.1016/j.earscirev.2008.03.001} } |
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Andreae, M.O., Jones, C.D. and Cox, P.M. | Strong present-day aerosol cooling implies a hot future | 2005 | Nature Vol. 435(7046), pp. 1187-1190 |
article | DOI URL |
Abstract: Atmospheric aerosols counteract the warming effects of anthropogenic greenhouse gases by an uncertain, but potentially large, amount. This in turn leads to large uncertainties in the sensitivity of climate to human perturbations, and therefore also in carbon cycle feedbacks and projections of climate change. In the future, aerosol cooling is expected to decline relative to greenhouse gas forcing, because of the aerosols' much shorter lifetime and the pursuit of a cleaner atmosphere. Strong aerosol cooling in the past and present would then imply that future global warming may proceed at or even above the upper extreme of the range projected by the Intergovernmental Panel on Climate Change. | |||||
BibTeX:
@article{andreae_strong_2005, author = {Andreae, M. O. and Jones, C. D. and Cox, P. M.}, title = {Strong present-day aerosol cooling implies a hot future}, journal = {Nature}, year = {2005}, volume = {435}, number = {7046}, pages = {1187--1190}, note = {Edition: 2005/07/01}, url = {://WOS:000230140500033 http://www.nature.com/nature/journal/v435/n7046/pdf/nature03671.pdf}, doi = {https://doi.org/10.1038/nature03671} } |
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Andreae, M.O., Artaxo, P., Fischer, H., Freitas, S.R., Gregoire, J.M., Hansel, A., Hoor, P., Kormann, R., Krejci, R., Lange, L., Lelieveld, J., Lindinger, W., Longo, K., Peters, W., de Reus, M., Scheeren, B., Dias, M., Strom, J., van Velthoven, P.F.J. and Williams, J. | Transport of biomass burning smoke to the upper troposphere by deep convection in the equatorial region | 2001 | Geophysical Research Letters Vol. 28(6), pp. 951-954 |
article | DOI URL |
Abstract: During LBA-CLAIRE-98, we found atmospheric layers with aged biomass smoke at altitudes textgreater10 km over Suriname. CO, CO2, acetonitrile, methyl chloride, hydrocarbons, NO, O-3, and aerosols were strongly enhanced in these layers. We estimate that 80-95% of accumulation mode aerosols had been removed during convective transport. Trajectories show that the plumes originated from large fires near the Brazil/Venezuela border during March 1998. This smoke was entrained into deep convection over the northern Amazon, transported out over the Pacific, and then returned to South America by the circulation around a large upper-level anticyclone. Our observations provide evidence for the importance of deep convection in the equatorial region as a mechanism to transport large amounts of pyrogenic pollutants into the upper troposphere. The entrainment of biomass smoke into tropical convective clouds may have significant effects on cloud microphysics and climate dynamics. | |||||
BibTeX:
@article{andreae_transport_2001, author = {Andreae, M. O. and Artaxo, P. and Fischer, H. and Freitas, S. R. and Gregoire, J. M. and Hansel, A. and Hoor, P. and Kormann, R. and Krejci, R. and Lange, L. and Lelieveld, J. and Lindinger, W. and Longo, K. and Peters, W. and de Reus, M. and Scheeren, B. and Dias, Mafs and Strom, J. and van Velthoven, P. F. J. and Williams, J.}, title = {Transport of biomass burning smoke to the upper troposphere by deep convection in the equatorial region}, journal = {Geophysical Research Letters}, year = {2001}, volume = {28}, number = {6}, pages = {951--954}, url = {://WOS:000167494200001 http://www.agu.org/pubs/crossref/2001/2000GL012391.shtml}, doi = {https://doi.org/10.1029/2000gl012391} } |
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Andreae, M.O., Artaxo, P., Brandao, C., Carswell, F.E., Ciccioli, P., da Costa, A.L., Culf, A.D., Esteves, J.L., Gash, J.H.C., Grace, J., Kabat, P., Lelieveld, J., Malhi, Y., Manzi, A.O., Meixner, F.X., Nobre, A.D., Nobre, C., Ruivo, M., Silva-Dias, M.A., Stefani, P., Valentini, R., von Jouanne, J. and Waterloo, M.J. | Biogeochemical cycling of carbon, water, energy, trace gases, and aerosols in Amazonia: The LBA-EUSTACH experiments | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: The biogeochemical cycling of carbon, water, energy, aerosols, and trace gases in the Amazon Basin was investigated in the project European Studies on Trace Gases and Atmospheric Chemistry as a Contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA-EUSTACH). We present an overview of the design of the project, the measurement sites and methods, and the meteorological conditions during the experiment. The main results from LBA-EUSTACH are: Eddy correlation studies in three regions of the Amazon Basin consistently show a large net carbon sink in the undisturbed rain forest. Nitrogen emitted by forest soils is subject to chemical cycling within the canopy space, which results in re-uptake of a large fraction of soil-derived NO(x) by the vegetation. The forest vegetation is both a sink and a source of volatile organic compounds, with net deposition being particularly important for partially oxidized organics. Concentrations of aerosol and cloud condensation nuclei (CCN) are highly seasonal, with a pronounced maximum in the dry (burning) season. High CCN concentrations from biomass burning have a pronounced impact on cloud microphysics, rainfall production mechanisms, and probably on large-scale climate dynamics. | |||||
BibTeX:
@article{andreae_biogeochemical_2002, author = {Andreae, M. O. and Artaxo, P. and Brandao, C. and Carswell, F. E. and Ciccioli, P. and da Costa, A. L. and Culf, A. D. and Esteves, J. L. and Gash, J. H. C. and Grace, J. and Kabat, P. and Lelieveld, J. and Malhi, Y. and Manzi, A. O. and Meixner, F. X. and Nobre, A. D. and Nobre, C. and Ruivo, Mdlp and Silva-Dias, M. A. and Stefani, P. and Valentini, R. and von Jouanne, J. and Waterloo, M. J.}, title = {Biogeochemical cycling of carbon, water, energy, trace gases, and aerosols in Amazonia: The LBA-EUSTACH experiments}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200022 http://www.agu.org/journals/jd/jd0217/2001JD000524/2001JD000524.pdf}, doi = {https://doi.org/10.1029/2001jd000524} } |
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Andreae, M.O., Artaxo, P., Beck, V., Bela, M., Freitas, S., Gerbig, C., Longo, K., Munger, J.W., Wiedemann, K.T. and Wofsy, S.C. | Carbon monoxide and related trace gases and aerosols over the Amazon Basin during the wet and dry seasons [BibTeX] |
2012 | Atmos. Chem. Phys. Vol. 12(13), pp. 6041-6065 |
article | DOI URL |
BibTeX:
@article{andreae_carbon_2012, author = {Andreae, M. O. and Artaxo, P. and Beck, V. and Bela, M. and Freitas, S. and Gerbig, C. and Longo, K. and Munger, J. W. and Wiedemann, K. T. and Wofsy, S. C.}, title = {Carbon monoxide and related trace gases and aerosols over the Amazon Basin during the wet and dry seasons}, journal = {Atmos. Chem. Phys.}, year = {2012}, volume = {12}, number = {13}, pages = {6041--6065}, url = {http://www.atmos-chem-phys.net/12/6041/2012/acp-12-6041-2012.pdf}, doi = {https://doi.org/10.5194/acp-12-6041-2012} } |
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Andreae, M.O., Acevedo, O.C., Araùjo, A., Artaxo, P., Barbosa, C.G.G., Barbosa, H.M.J., Brito, J., Carbone, S., Chi, X., Cintra, B.B.L., Silva, N.F.d., Dias, N.L., Dias-Júnior, C.Q., Ditas, F., Ditz, R., Godoi, A.F.L., Godoi, R.H.M., Heimann, M., Hoffmann, T., Kesselmeier, J., Könemann, T., Krüger, M.L., Lavric, J.V., Manzi, A.O., Lopes, A.P., Martins, D.L., Mikhailov, E.F., Moran-Zuloaga, D., Nelson, B.W., Nölscher, A.C., Santos Nogueira, D., Piedade, M.T.F., Pöhlker, C., Pöschl, U., Quesada, C.A., Rizzo, L.V., Ro, C.-U., Ruckteschler, N., Sá, L.D.A., Oliveira Sá, M.d., Sales, C.B., Santos, R.M.N.d., Saturno, J., Schöngart, J., Sörgel, M., Souza, C.M.d., Souza, R.A.F.d., Su, H., Targhetta, N., Tóta, J., Trebs, I., Trumbore, S., Eijck, A.v., Walter, D., Wang, Z., Weber, B., Williams, J., Winderlich, J., Wittmann, F., Wolff, S. and Yáñez-Serrano, A.M. | The Amazon Tall Tower Observatory (ATTO): overview of pilot measurements on ecosystem ecology, meteorology, trace gases, and aerosols [BibTeX] |
2015 | Atmos. Chem. Phys. Vol. 15, pp. 10723-10776 |
article | DOI |
BibTeX:
@article{andreae_amazon_2015, author = {Andreae, M. O. and Acevedo, O. C. and Araùjo, A. and Artaxo, P. and Barbosa, C. G. G. and Barbosa, H. M. J. and Brito, J. and Carbone, S. and Chi, X. and Cintra, B. B. L. and Silva, N. F. da and Dias, N. L. and Dias-Júnior, C. Q. and Ditas, F. and Ditz, R. and Godoi, A. F. L. and Godoi, R. H. M. and Heimann, M. and Hoffmann, T. and Kesselmeier, J. and Könemann, T. and Krüger, M. L. and Lavric, J. V. and Manzi, A. O. and Lopes, A. P. and Martins, D. L. and Mikhailov, E. F. and Moran-Zuloaga, D. and Nelson, B. W. and Nölscher, A. C. and Santos Nogueira, D. and Piedade, M. T. F. and Pöhlker, C. and Pöschl, U. and Quesada, C. A. and Rizzo, L. V. and Ro, C.-U. and Ruckteschler, N. and Sá, L. D. A. and Oliveira Sá, M. de and Sales, C. B. and Santos, R. M. N. dos and Saturno, J. and Schöngart, J. and Sörgel, M. and Souza, C. M. de and Souza, R. A. F. de and Su, H. and Targhetta, N. and Tóta, J. and Trebs, I. and Trumbore, S. and Eijck, A. van and Walter, D. and Wang, Z. and Weber, B. and Williams, J. and Winderlich, J. and Wittmann, F. and Wolff, S. and Yáñez-Serrano, A. M.}, title = {The Amazon Tall Tower Observatory (ATTO): overview of pilot measurements on ecosystem ecology, meteorology, trace gases, and aerosols}, journal = {Atmos. Chem. Phys.}, year = {2015}, volume = {15}, pages = {10723--10776}, doi = {https://doi.org/10.5194/acp-15-10723-2015} } |
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Andreae, M.O. | Correlation between cloud condensation nuclei concentration and aerosol optical thickness in remote and polluted regions [BibTeX] |
2009 | Atmos. Chem. Phys. Vol. 9(2), pp. 543-556 |
article | DOI URL |
BibTeX:
@article{andreae_correlation_2009, author = {Andreae, M. O.}, title = {Correlation between cloud condensation nuclei concentration and aerosol optical thickness in remote and polluted regions}, journal = {Atmos. Chem. Phys.}, year = {2009}, volume = {9}, number = {2}, pages = {543--556}, url = {https://acp.copernicus.org/articles/9/543/2009/}, doi = {https://doi.org/10.5194/acp-9-543-2009} } |
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Andreae, M.O. | A New Look at Aging Aerosols [BibTeX] |
2009 | Science Vol. 326(5959), pp. 1493-1494 |
article | DOI URL |
BibTeX:
@article{andreae_new_2009, author = {Andreae, Meinrat O.}, title = {A New Look at Aging Aerosols}, journal = {Science}, year = {2009}, volume = {326}, number = {5959}, pages = {1493--1494}, note = {Edition: 2009/12/17}, url = {://WOS:000272623600045 http://www.sciencemag.org/content/326/5959/1493}, doi = {https://doi.org/10.1126/science.1183158} } |
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Andrade, V.d., Silva, M., da Costa, J., Oliveira, E. and Malhi, Y. | Variação dos fluxos de CO2 e da radiação fotossinteticamente ativa (PAR) em ecossistema de manguezal amazônico na região de Bragança, PA [BibTeX] |
2007 | Revista Ciência e Natura Vol. Especial Micrometeorologia, pp. 121-124 |
article | |
BibTeX:
@article{andrade_variacao_2007, author = {Andrade, V.M.S. de and Silva, M.A.V. and da Costa, J.M.N. and Oliveira, E.C. and Malhi, Y.}, title = {Variação dos fluxos de CO2 e da radiação fotossinteticamente ativa (PAR) em ecossistema de manguezal amazônico na região de Bragança, PA}, journal = {Revista Ciência e Natura}, year = {2007}, volume = {Especial Micrometeorologia}, pages = {121--124} } |
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Andrade, N.L.R., Sanches, L., Aguiar, R.G., Ribeiro, J.G.S. and Pinto Junior, O.B. | Variabilidade sazonal e interanual do microclima em área de floresta no sudoeste da Amazônia [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 169-176 |
article | |
BibTeX:
@article{andrade_variabilidade_2016, author = {Andrade, Nara L R and Sanches, Luciana and Aguiar, Renata Gonçalves and Ribeiro, J. G. S. and Pinto Junior, O. B.}, title = {Variabilidade sazonal e interanual do microclima em área de floresta no sudoeste da Amazônia}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {169--176} } |
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Andrade Aguiar, R., Sanches, L., Alves, E. and Nogueira J.S., N. | Partição do Saldo de Radiação em Áreas de Floresta Amazônica e Floresta de Transição Amazônia-Cerrado [BibTeX] |
2009 | Revista Brasileira de Meteorologia Vol. 24, pp. 346-355 |
article | |
BibTeX:
@article{andrade_particao_2009, author = {Andrade, Aguiar, R.G.; Sanches, L.; Alves, E.C.R.F.; Nogueira, J.S., N.L.R.}, title = {Partição do Saldo de Radiação em Áreas de Floresta Amazônica e Floresta de Transição Amazônia-Cerrado}, journal = {Revista Brasileira de Meteorologia}, year = {2009}, volume = {24}, pages = {346--355} } |
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Andrade, S., Pinto Júnior, L., Dias, O.B., C.A.A., N. and N.L.R., J.S. | Macro-nutrientes no lençol freático em Floresta Intacta, Floresta de Manejo e Pastagem no norte de Mato Grosso [BibTeX] |
2008 | Acta Amazonica Vol. 38(4), pp. 667- 672 |
article | |
BibTeX:
@article{andrade_macro-nutrientes_2008, author = {Andrade, Sanches, L., Pinto Júnior, O.B., Dias, C.A.A., Nogueira, J.S., N.L.R.}, title = {Macro-nutrientes no lençol freático em Floresta Intacta, Floresta de Manejo e Pastagem no norte de Mato Grosso}, journal = {Acta Amazonica}, year = {2008}, volume = {38}, number = {4}, pages = {667-- 672} } |
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Andrade, N., Sandwiches, L., Zeilhofer, P., Ribeiro, J.S., Barbino, G. and DeMusis, C. | Different spatial and temporal arrangements for validating the latent heat flux obtained using the MOD16 product in a forest in the Western Amazon. [BibTeX] |
2023 | Int J Hydro. Vol. 7(1), pp. 18-25 |
article | DOI |
BibTeX:
@article{andrade_different_2023, author = {Andrade, NLR. and Sandwiches, L. and Zeilhofer, P. and Ribeiro, J.G.de S. and Barbino, G.C. and DeMusis, C.R.}, title = {Different spatial and temporal arrangements for validating the latent heat flux obtained using the MOD16 product in a forest in the Western Amazon.}, journal = {Int J Hydro.}, year = {2023}, volume = {7}, number = {1}, pages = {18--25}, doi = {https://doi.org/10.15406/ijh.2023.07.00335} } |
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Andrade, A.M.D.d. and Moura, M.A.L. | Condensação a Superfície na Amazônia em Área de Pastagem Durante O Experimento LBA/SMOCC: Estudo de Casos [BibTeX] |
2011 | Revista Brasileira de Meteorologia Vol. 26(3), pp. 339 - 348 |
article | |
BibTeX:
@article{andrade_condensacao_2011, author = {Andrade, A. M. D. de and Moura, M. A. L.}, title = {Condensação a Superfície na Amazônia em Área de Pastagem Durante O Experimento LBA/SMOCC: Estudo de Casos}, journal = {Revista Brasileira de Meteorologia}, year = {2011}, volume = {26}, number = {3}, pages = {339 -- 348} } |
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Andrade, A.M.D. and Moura. M. A., L. | Ocorrência de um evento de condensação à superfície em área de pastagem na Amazônia [BibTeX] |
2009 | Revista Ciência e Natura Vol. Edição Especial em Micrometeorologia, pp. 125-128 |
article | |
BibTeX:
@article{andrade_ocorrencia_2009, author = {Andrade, A. M. D and L., Moura. M. A.}, title = {Ocorrência de um evento de condensação à superfície em área de pastagem na Amazônia}, journal = {Revista Ciência e Natura}, year = {2009}, volume = {Edição Especial em Micrometeorologia}, pages = {125--128} } |
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Anderson, N.F., Grainger, C.A. and Stith, J.L. | Characteristics of strong updrafts in precipitation systems over the central tropical pacific ocean and in the Amazon | 2005 | Journal of Applied Meteorology Vol. 44(5), pp. 731-738 |
article | DOI URL |
Abstract: Airborne in situ measurements of updrafts in tropical convective storms were analyzed to determine the similarities and differences between updrafts in a tropical continental and a tropical oceanic region. Two hundred fifteen updraft cores from the Tropical Rainfall Measuring Mission (TRMM) component of the Large Scale Biosphere-Atmosphere (LBA) experiment (tropical continental wet season) and 377 updraft cores from the Kwajalein Experiment (KWAJEX) (tropical oceanic) were analyzed in a similar manner to that of previous studies of tropical updrafts. Average speed, maximum speed, width, and mass flux of the updraft cores from the TRMM-LBA and KWAJEX were generally similar to each other and also were similar to results from previous studies of tropical updrafts. | |||||
BibTeX:
@article{anderson_characteristics_2005, author = {Anderson, N. F. and Grainger, C. A. and Stith, J. L.}, title = {Characteristics of strong updrafts in precipitation systems over the central tropical pacific ocean and in the Amazon}, journal = {Journal of Applied Meteorology}, year = {2005}, volume = {44}, number = {5}, pages = {731--738}, url = {://WOS:000230003400013 http://journals.ametsoc.org/doi/pdf/10.1175/JAM2231.1}, doi = {https://doi.org/10.1175/jam2231.1} } |
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Anderson, L.O., Shimabukuro, Y.E., Defries, R.S. and Morton, D. | Assessment of deforestation in near real time over the Brazilian Amazon using multitemporal fraction images derived from terra MODIS | 2005 | Ieee Geoscience and Remote Sensing Letters Vol. 2(3), pp. 315-318 |
article | DOI URL |
Abstract: We present a methodology for rapidly assessing deforestation over the Amazon region needed for policy intervention. We use soil fraction images generated from Moderate Resolution Imaging Spectroradiometer (MODIS) data at 250-m spatial resolution. Results showed reasonable agreement with higher resolution Landsat data (r(2) = 0.73) for our study area. MODIS data are promising for near real-time deforestation monitoring, previously not practical with Landsat data. | |||||
BibTeX:
@article{anderson_assessment_2005, author = {Anderson, L. O. and Shimabukuro, Y. E. and Defries, R. S. and Morton, D.}, title = {Assessment of deforestation in near real time over the Brazilian Amazon using multitemporal fraction images derived from terra MODIS}, journal = {Ieee Geoscience and Remote Sensing Letters}, year = {2005}, volume = {2}, number = {3}, pages = {315--318}, url = {://WOS:000230796100016 http://ieeexplore.ieee.org/ielx5/8859/31483/01468089.pdf?tp=&arnumber=1468089&isnumber=31483}, doi = {https://doi.org/10.1109/lgrs.2005.850364} } |
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Anderson, L.O., Shimabukuro, Y.E. and Arai, E. | Multitemporal fraction images derived from Terra MODIS data for analysing land cover change over the Amazon region [BibTeX] |
2005 | International Journal of Remote Sensing Vol. 26(11), pp. 2251-2257 |
article | DOI URL |
BibTeX:
@article{anderson_multitemporal_2005, author = {Anderson, L. O. and Shimabukuro, Y. E. and Arai, E.}, title = {Multitemporal fraction images derived from Terra MODIS data for analysing land cover change over the Amazon region}, journal = {International Journal of Remote Sensing}, year = {2005}, volume = {26}, number = {11}, pages = {2251--2257}, url = {://WOS:000230646900001 http://www.tandfonline.com/doi/abs/10.1080/01431160310001620795}, doi = {https://doi.org/10.1080/01431160310001620795} } |
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Anderson, L.O., Malhi, Y., Ladle, R.J., Aragao, L.E.O.C., Shimabukuro, Y., Phillips, O.L., Baker, T., Costa, A.C.L., Espejo, J.S., Higuchi, N., Laurance, W.F., Lopez-Gonzalez, G., Monteagudo, A., Nunez-Vargas, P., Peacock, J., Quesada, C.A. and Almeida, S. | Influence of landscape heterogeneity on spatial patterns of wood productivity, wood specific density and above ground biomass in Amazonia | 2009 | Biogeosciences Vol. 6(9), pp. 1883-1902 |
article | URL |
Abstract: Long-term studies using the RAINFOR network of forest plots have generated significant insights into the spatial and temporal dynamics of forest carbon cycling in Amazonia. In this work, we map and explore the landscape context of several major RAINFOR plot clusters using Landsat ETM+ satellite data. In particular, we explore how representative the plots are of their landscape context, and test whether bias in plot location within landscapes may be influencing the regional mean values obtained for important forest biophysical parameters. Specifically, we evaluate whether the regional variations in wood productivity, wood specific density and above ground biomass derived from the RAINFOR network could be driven by systematic and unintentional biases in plot location. Remote sensing data covering 45 field plots were aggregated to generate landscape maps to identify the specific physiognomy of the plots. In the Landsat ETM+ data, it was possible to spectrally differentiate three types of terra firme forest, three types of forests over Paleovarzea geomorphologycal formation, two types of bamboo-dominated forest, palm forest, Heliconia monodominant vegetation, swamp forest, disturbed forests and land use areas. Overall, the plots were generally representative of the forest physiognomies in the landscape in which they are located. Furthermore, the analysis supports the observed regional trends in those important forest parameters. This study demonstrates the utility of landscape scale analysis of forest physiognomies for validating and supporting the finds of plot based studies. Moreover, the more precise geolocation of many key RAINFOR plot clusters achieved during this research provides important contextual information for studies employing the RAINFOR database. | |||||
BibTeX:
@article{anderson_influence_2009, author = {Anderson, L. O. and Malhi, Y. and Ladle, R. J. and Aragao, L. E. O. C. and Shimabukuro, Y. and Phillips, O. L. and Baker, T. and Costa, A. C. L. and Espejo, J. S. and Higuchi, N. and Laurance, W. F. and Lopez-Gonzalez, G. and Monteagudo, A. and Nunez-Vargas, P. and Peacock, J. and Quesada, C. A. and Almeida, S.}, title = {Influence of landscape heterogeneity on spatial patterns of wood productivity, wood specific density and above ground biomass in Amazonia}, journal = {Biogeosciences}, year = {2009}, volume = {6}, number = {9}, pages = {1883--1902}, url = {://WOS:000270321800005} } |
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Anderson, L.O., Malhi, Y., Aragao, L.E.O.C., Ladle, R., Arai, E., Barbier, N. and Phillips, O. | Remote sensing detection of droughts in Amazonian forest canopies | 2010 | New Phytologist Vol. 187(3), pp. 733-750 |
article | DOI URL |
Abstract: PtextgreaterRemote sensing data are a key tool to assess large forested areas, where limitations such as accessibility and lack of field measurements are prevalent. Here, we have analysed datasets from moderate resolution imaging spectroradiometer (MODIS) satellite measurements and field data to assess the impacts of the 2005 drought in Amazonia. We combined vegetation indices (VI) and climatological variables to evaluate the spatiotemporal patterns associated with the 2005 drought, and explore the relationships between remotely-sensed indices and forest inventory data on tree mortality. There were differences in results based on c4 and c5 MODIS products. C5 VI showed no spatial relationship with rainfall or aerosol optical depth; however, distinct regions responded significantly to the increased radiation in 2005. The increase in the Enhanced VI (EVI) during 2005 showed a significant positive relationship (P textless 0.07) with the increase of tree mortality. By contrast, the normalized difference water index (NDWI) exhibited a significant negative relationship (P textless 0.09) with tree mortality. Previous studies have suggested that the increase in EVI during the 2005 drought was associated with a positive response of forest photosynthesis to changes in the radiation income. We discuss the evidence that this increase could be related to structural changes in the canopy. | |||||
BibTeX:
@article{anderson_remote_2010, author = {Anderson, Liana O. and Malhi, Yadvinder and Aragao, Luiz E. O. C. and Ladle, Richard and Arai, Egidio and Barbier, Nicolas and Phillips, Oliver}, title = {Remote sensing detection of droughts in Amazonian forest canopies}, journal = {New Phytologist}, year = {2010}, volume = {187}, number = {3}, pages = {733--750}, note = {Edition: 2010/07/28}, url = {://WOS:000280122500017 http://onlinelibrary.wiley.com/store/10.1111/j.1469-8137.2010.03355.x/asset/j.1469-8137.2010.03355.x.pdf?v=1&t=h6hx987c&s=e8ae577d690b31432b76fbd6ee77e6d63c8aa0a4}, doi = {https://doi.org/10.1111/j.1469-8137.2010.03355.x} } |
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Anderson, L.O., Aragao, L.E.O.C., Shimabukuro, Y.E., Almeida, S. and Huete, A. | Fraction images for monitoring intra-annual phenology of different vegetation physiognomies in Amazonia | 2011 | International Journal of Remote Sensing Vol. 32(2), pp. 387-408 |
article | DOI URL |
Abstract: In this study we investigate the potential of fraction images derived from a linear spectral mixture model to detect vegetation phenology in Amazonia, and evaluate their relationships with the Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indices. Time series of MODIS 250-m data over three contrasting land cover types in the Amazon were used in conjunction with rainfall data, a land cover map and a forest inventory survey to support the interpretation of our findings. Each vegetation physiognomy was characterized by a particular intra-annual variability detected by a combination of the fraction images. Both vegetation and shade fractions were important to evaluate the seasonality of the open tropical forest (OTF). The association of these results with forest inventory data and the literature suggests that Enhanced Vegetation Index (EVI) and vegetation fraction images are sensitive to structural changes in the canopy of OTF. In cerrado grassland (CG) the phenology was better characterized by combined soil and vegetation fractions. Soybean (SB) areas were characterized by the highest ranges in the vegetation and soil fraction images. Vegetation fraction and vegetation indices for the OTF showed a significant positive relationship with EVI but not with Normalized Difference Vegetation Index (NDVI). Significant relationships for vegetation fraction and vegetation indices were also found for the CG and soybean areas. In contrast to vegetation index approaches to monitoring phenology, fraction images provide additional information that allows a more comprehensive exploration of the spectral and structural changes in vegetation formations. | |||||
BibTeX:
@article{anderson_fraction_2011, author = {Anderson, Liana O. and Aragao, Luiz E. O. C. and Shimabukuro, Yosio E. and Almeida, Samuel and Huete, Alfredo}, title = {Fraction images for monitoring intra-annual phenology of different vegetation physiognomies in Amazonia}, journal = {International Journal of Remote Sensing}, year = {2011}, volume = {32}, number = {2}, pages = {387--408}, url = {://WOS:000287026900006 http://www.tandfonline.com/doi/abs/10.1080/01431160903474921}, doi = {https://doi.org/10.1080/01431160903474921} } |
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Anderson, L.O., Aragão, L., Gloor, M., Arai, E., Adami, M., Saatchi, S., Malhi, Y., Shimabukuro, Y., Barlow, J., Berenguer, E. and Duarte, V. | Disentangling the contribution of multiple land covers to fire-mediated carbon emission in Amazonia during the 2010 drought [BibTeX] |
2015 | Global Biogeochemical Cycles Vol. 28, pp. 1739-1753 |
article | DOI |
BibTeX:
@article{anderson_disentangling_2015, author = {Anderson, Liana O. and Aragão, L.E.O.C. and Gloor, M. and Arai, E. and Adami, M. and Saatchi, S. and Malhi, Y. and Shimabukuro, Y. and Barlow, J. and Berenguer, E. and Duarte, V.}, title = {Disentangling the contribution of multiple land covers to fire-mediated carbon emission in Amazonia during the 2010 drought}, journal = {Global Biogeochemical Cycles}, year = {2015}, volume = {28}, pages = {1739--1753}, doi = {https://doi.org/10.1002/2014GB005008} } |
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Anderson, L. | Biome-Scale Forest Properties in Amazonia Based on Field and Satellite Observations [BibTeX] |
2012 | Remote Sensing Vol. 4(5), pp. 1245-1271 |
article | DOI URL |
BibTeX:
@article{anderson_biome-scale_2012, author = {Anderson, L.O.}, title = {Biome-Scale Forest Properties in Amazonia Based on Field and Satellite Observations}, journal = {Remote Sensing}, year = {2012}, volume = {4}, number = {5}, pages = {1245--1271}, url = {http://www.mdpi.com/2072-4292/4/5/1245/pdf}, doi = {https://doi.org/10.3390/rs4051245} } |
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Anderson, A., L.E.O.C., L., Shimabukuro, A. and L.O., Y.E. | Detecção de cicatrizes de áreas queimadas baseada no modelo linear de mistura espectral e imagens índice de vegetação utilizando dados multi-temporais do sensor MODIS/TERRA no estado do Mato Grosso, Amazônia brasileira [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 445-456 |
article | |
BibTeX:
@article{anderson_deteccao_2005, author = {Anderson, Aragão, L.E.O.C., Lima, A., Shimabukuro, Y.E., L.O.}, title = {Detecção de cicatrizes de áreas queimadas baseada no modelo linear de mistura espectral e imagens índice de vegetação utilizando dados multi-temporais do sensor MODIS/TERRA no estado do Mato Grosso, Amazônia brasileira}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {445--456} } |
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Anderson, L., Cheek, D., Aragão, L., Andere, L. and Duarte, B. | Development of a Point-based Method for Map Validation and Confidence Interval Estimation: A Case Study of Burned Areas in Amazonia [BibTeX] |
2017 | J Remote Sensing & GIS Vol. 6(193) |
article | DOI |
BibTeX:
@article{anderson_development_2017, author = {Anderson, LO. and Cheek, D. and Aragão, LE. and Andere, L. and Duarte, B.}, title = {Development of a Point-based Method for Map Validation and Confidence Interval Estimation: A Case Study of Burned Areas in Amazonia}, journal = {J Remote Sensing & GIS}, year = {2017}, volume = {6}, number = {193}, doi = {https://doi.org/10.4172/2469-4134.1000193} } |
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Ananias, D.S., Souza, E.B., Souza, P.F.S., Souza, A.M.l., Vitorino, M.I., Teixeira, G.M. and Ferreira, D.B.S. | Climatologia da estrutura vertical da atmosfera em novembro para Belém-PA [BibTeX] |
2010 | Revista Brasileira de Meteorologia Vol. 25, pp. 218-226 |
article | |
BibTeX:
@article{ananias_climatologia_2010, author = {Ananias, D. S. and Souza, E. B. and Souza, P. F. S. and Souza, A. M. l. and Vitorino, M. I. and Teixeira, G. M. and Ferreira, D. B. S.}, title = {Climatologia da estrutura vertical da atmosfera em novembro para Belém-PA}, journal = {Revista Brasileira de Meteorologia}, year = {2010}, volume = {25}, pages = {218--226} } |
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Anagnostou, E.N., Negri, A.J. and Adler, R.F. | Statistical adjustment of satellite microwave monthly rainfall estimates over Amazonia | 1999 | Journal of Applied Meteorology Vol. 38(11), pp. 1590-1598 |
article | DOI URL |
Abstract: A technique is described for quantifying nonlinear adjustment to the half-degree monthly rainfall estimates over land, derived from the Special Sensor Microwave Imager (SSM/I) observations. The technique uses a function that represents the distortion between the probability distributions of SSM/I and rain gauge half-degree monthly rainfall. The proposed adjustment procedure is assessed and evaluated with a 10-yr period (1988-97) of SSM/I observations over the northern South America region (15 degrees N-15 degrees S, 80 degrees-35 degrees W), which includes the Amazon basin. The rain estimates are derived from the National Aeronautics and Space Administration's Goddard Profiling (GPROF) algorithm instantaneous rain-rate retrievals, averaged in half-degree areas and aggregated into monthly accumulations. Monthly rain accumulations from a network of 650 rain gauges distributed across the Amazon basin and the state of Ceara in northeastern Brazil are used for calibration and validation, respectively. Assessment of the adjustment relationship with the validation dataset shows an overall 45% GPROF-gauge root-mean-square (rms) difference reduction with respect to no adjustment, which is due mainly to elimination of the mean bias, and a respective 10% increase in the GPROF-gauge correlation. The rms difference between 5 degrees gridbox monthly rain averages of adjusted GPROF and rain gauges is 23% of the mean rain, and the corresponding correlation coefficient is 0.94. | |||||
BibTeX:
@article{anagnostou_statistical_1999, author = {Anagnostou, E. N. and Negri, A. J. and Adler, R. F.}, title = {Statistical adjustment of satellite microwave monthly rainfall estimates over Amazonia}, journal = {Journal of Applied Meteorology}, year = {1999}, volume = {38}, number = {11}, pages = {1590--1598}, url = {://WOS:000083842200003 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0450%281999%29038%3C1590%3ASAOSMM%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0450(1999)038%3C1590:saosmm%3E2.0.co;2} } |
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Anagnostou, E.N., Negri, A.J. and Adler, R.F. | A satellite infrared technique for diurnal rainfall variability studies | 1999 | Journal of Geophysical Research-Atmospheres Vol. 104(D24), pp. 31477-31488 |
article | DOI URL |
Abstract: The development of a satellite infrared technique for estimating convective and stratiform rainfall area and volume and its application in studying the diurnal variability of rainfall in Amazonia are presented. Cloud systems are defined in the technique by the 253 K infrared (IR) temperature isotherm. The convective and stratiform rain areas within these cloud systems are then related to morphologic characteristics of the IR temperature fields. Rainfall rates are assigned to the defined convective and stratiform areas using IR-microwave-derived rain rate probability matching relationships. The training data set consists of three months of collocated IR observations and microwave (MW) rain rate retrievals over a region in the Amazon Basin. Evaluation of instantaneous rain rate estimates over a second independent region in the Amazon showed 25% (-40%) systematic error and 55% (70%) residual random error standard deviation in morning (evening) MW overpasses. The method is used to derive the mean diurnal cycle of rainfall and investigate the relative contribution from its convective and stratiform components. Finally, the technique is applied to study the time evolution of rainfall and the transition from convective to stratiform over selected sites in the Amazon. | |||||
BibTeX:
@article{anagnostou_satellite_1999, author = {Anagnostou, E. N. and Negri, A. J. and Adler, R. F.}, title = {A satellite infrared technique for diurnal rainfall variability studies}, journal = {Journal of Geophysical Research-Atmospheres}, year = {1999}, volume = {104}, number = {D24}, pages = {31477--31488}, url = {://WOS:000084692900044 http://www.agu.org/journals/jd/v104/iD24/1999JD900157/1999JD900157.pdf}, doi = {https://doi.org/10.1029/1999jd900157} } |
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Anagnostou, E.N., Morales, C.A. and Dinku, T. | The use of TRMM precipitation radar observations in determining ground radar calibration biases | 2001 | Journal of Atmospheric and Oceanic Technology Vol. 18(4), pp. 616-628 |
article | DOI URL |
Abstract: Since the successful launch of the Tropical Rainfall Measuring Mission (TRMM) satellite, measurements of a wide variety of precipitating systems have been obtained with unprecedented detail from the first space-based radar [precipitation radar (PR)]. In this research, a methodology is developed that matches coincident PR and ground-based volume scanning weather radar observations in a common earth parallel three-dimensional Cartesian grid. The data matching is performed in a way that minimizes uncertainties associated with the type of weather seen by the radars, grid resolution, and differences in radar sensitivities, sampling volumes, viewing angles, and radar frequencies. The authors present comparisons of reflectivity observations from the PR and several U.S. weather surveillance Doppler radars (WSR-88D) as well as research radars from the TRMM field campaigns in Kwajalein Atoll and the Large Biosphere Atmospheric (LBA) Experiment. Correlation values above 0.8 are determined between PR and ground radar matched data for levels above the zero isotherm. The reflectivity difference statistics derived from the matched data reveal radar systems with systematic differences ranging from +2 to -7 dB. The authors argue that the main candidate for systematic differences exceeding 1 to 1.5 dB is the ground radar system calibration bias. To verify this argument, the authors used PR comparisons against well-calibrated ground-based systems, which showed systematic differences consistently less than 1.5 dB. Temporal analysis of the PR versus ground radar systematic differences reveals radar sites with up to 4.5-dB bias changes within periods of two to six months. Similar evaluation of the PR systematic difference against stable ground radar systems shows bias fluctuations of less than 0.8 dB. It is also shown that bias adjustment derived from the methodology can have significant impact on the hydrologic applications of ground-based radar measurements. The proposed scheme can be a useful tool for the systematic monitoring of ground radar biases and the studying of its effect. | |||||
BibTeX:
@article{anagnostou_use_2001, author = {Anagnostou, E. N. and Morales, C. A. and Dinku, T.}, title = {The use of TRMM precipitation radar observations in determining ground radar calibration biases}, journal = {Journal of Atmospheric and Oceanic Technology}, year = {2001}, volume = {18}, number = {4}, pages = {616--628}, url = {://WOS:000168229400010 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0426%282001%29018%3C0616%3ATUOTPR%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0426(2001)018%3C0616:tuotpr%3E2.0.co;2} } |
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Anagnostou, E.N. and Morales, C.A. | Rainfall estimation from TOGA radar observations during LBA field campaign | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: The TRMM Large Scale Biosphere-Atmosphere (LBA) experiment, conducted between January and February of 1999 in Southwest Amazon, deployed among other instruments NASA's C-band Doppler radar (TOGA) and four dense rain gauge networks. This paper presents a procedure devised to derive surface rainfall rate estimates from combination of TOGA observations and the in situ rain gauge rainfall measurements. The spatial and temporal scales considered are 2 x 2 km(2) grids of instantaneous to hourly rain accumulations. The procedure includes evaluation of TOGA calibration through comparisons with TRMM Precipitation Radar (PR) data and implementation of an optimal quantitative precipitation estimation (QPE) algorithm. Comparisons with PR indicated a 4-dB calibration offset occurring in the later two thirds of the observation period. The implemented QPE algorithm applies a parameter that differentiates the Z-R conversion in convective and stratiform regimes and a stochastic filtering approach for estimation of mean-field bias on the basis of radar-rain gauge comparisons at the hourly timescale. The calibration of the algorithm parameter values is formulated as a global optimization problem, which is solved by minimizing the radar-rain gauge rainfall accumulation root-mean-square (rms) difference at the hourly timescale. A random resampling calibration/validation exercise is performed to evaluate the algorithm performance and its sensitivity to parameter values. Validation against gauges shows that the algorithm produces unbiased estimates with similar to57% relative RMS difference at the hourly scale. Comparison with S-POL rain estimates showed good correlation (0.9) but some overestimation (9%). Rainfall products are used to derive rainfall statistics for two distinct meteorological low-level wind regimes (easterly and westerly) that occurred during LBA. Finally, instantaneous rain estimates are compared against TRMM PR rainfall profiles for six coincident storm cases showing high correlation (0.9) and low (7%) systematic difference (PR overestimation). | |||||
BibTeX:
@article{anagnostou_rainfall_2002, author = {Anagnostou, E. N. and Morales, C. A.}, title = {Rainfall estimation from TOGA radar observations during LBA field campaign}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180466200024 http://www.agu.org/journals/jd/jd0217/2001JD000377/2001JD000377.pdf}, doi = {https://doi.org/10.1029/2001jd000377} } |
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Anacleto, F., Diniz-Filho, A.A., J.A.F., F. and T.C.S., L.G. | Seleção de áreas de interesse ecológico através de sensoriamento remoto e de otimização matemática: um estudo de caso no município de Cocalinho, MT [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 437 - 444 |
article | |
BibTeX:
@article{anacleto_selecao_2005, author = {Anacleto, Ferreira, A.A., Diniz-Filho, J.A.F., Ferreira, L.G., T.C.S.}, title = {Seleção de áreas de interesse ecológico através de sensoriamento remoto e de otimização matemática: um estudo de caso no município de Cocalinho, MT}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {437 -- 444} } |
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Anabor, A., Moraes, O.C. and O.L.L., V.O. | Variação rítmica dos sistemas convectivos na região Amazônica [BibTeX] |
2003 | Revista Ciência e Natura Vol. Especial, pp. 237 - 242 |
article | |
BibTeX:
@article{anabor_variacao_2003, author = {Anabor, Acevedo, O.C., Moraes, O.L.L., V. O.}, title = {Variação rítmica dos sistemas convectivos na região Amazônica}, journal = {Revista Ciência e Natura}, year = {2003}, volume = {Especial}, pages = {237 -- 242} } |
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Amaral, J.H.F., Melack, J.M., Barbosa, P.M., Borges, A.V., Kasper, D., Cortés, A.C., Zhou, W., MacIntyre, S. and Forsberg, B.R. | Inundation, Hydrodynamics and Vegetation Influence Carbon Dioxide Concentrations in Amazon Floodplain Lakes | 2022 | Ecosystems Vol. 25(4), pp. 911-930 |
article | DOI URL |
Abstract: Extensive floodplains and numerous lakes in the Amazon basin are well suited to examine the role of floodable lands within the context of the sources and processing of carbon within inland waters. We measured diel, seasonal and inter-annual variations of CO2 concentrations and related environmental variables in open water and flooded vegetation and estimated their habitat area using remote sensing in a representative Amazon floodplain lake, Lake Janauacá. Variability in CO2 concentrations in open water resulted from changes in the extent of inundation and exchange with vegetated habitats. Depth-averaged values of CO2 in the open water of the lake, 157 ± 91 µM (mean ± SD), were less than those in an embayment near aquatic vegetation, 285 ± 116 µM, and were variable over 24-h periods at both sites. Within floating herbaceous plant mats, the mean concentration was 275 ± 77 µM, while in flooded forests it was 217 ± 78 µM. The best statistical model that included CO2 in aquatic plant mats, water clarity, rate of change in water level and chlorophyll-a concentrations explained around 90% of the variability in CO2 concentration. Three-dimensional hydrodynamic modeling demonstrated that diel differences in water temperature between plant mats and open water as well as basin-scale motions caused lateral exchanges of CO2 between vegetated habitats and open water. Our findings extend understanding of CO2 in tropical lakes and floodplains with measurements and models that emphasize the importance of flooded forests and aquatic herbaceous plants fringing floodplain lakes as sources of CO2 to open waters. | |||||
BibTeX:
@article{amaral_inundation_2022, author = {Amaral, João Henrique Fernandes and Melack, John Michael and Barbosa, Pedro Maia and Borges, Alberto V. and Kasper, Daniele and Cortés, Alicia Cortes and Zhou, Wencai and MacIntyre, Sally and Forsberg, Bruce Rider}, title = {Inundation, Hydrodynamics and Vegetation Influence Carbon Dioxide Concentrations in Amazon Floodplain Lakes}, journal = {Ecosystems}, year = {2022}, volume = {25}, number = {4}, pages = {911--930}, url = {https://doi.org/10.1007/s10021-021-00692-y}, doi = {https://doi.org/10.1007/s10021-021-00692-y} } |
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Amaral, J.H.F., Borges, A.V., Melack, J.M., Sarmento, H., Barbosa, P.M., Kaspera, D., Melo, M.L., DanielaDe, F.-W., Silva, J.S. and Forsberg, B.R. | Influence of plankton metabolism and mixing depth on CO2 dynamics in an Amazon floodplain lake [BibTeX] |
2018 | Science of The Total Environment Volume Vol. 630, pp. 1381-1393 |
article | DOI |
BibTeX:
@article{amaral_influence_2018, author = {Amaral, João Henrique F. and Borges, Alberto V. and Melack, John M. and Sarmento, Hugo and Barbosa, Pedro M. and Kaspera, Daniele and Melo, Michaela L.de and DanielaDe, Fex-Wolf. and Silva, Jonismar S.da and Forsberg, Bruce R.}, title = {Influence of plankton metabolism and mixing depth on CO2 dynamics in an Amazon floodplain lake}, journal = {Science of The Total Environment Volume}, year = {2018}, volume = {630}, pages = {1381--1393}, doi = {https://doi.org/10.1016/j.scitotenv.2018.02.331} } |
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Amacher, G.S., Merry, F.D. and Bowman, M.S. | Smallholder timber sale decisions on the Amazon frontier | 2009 | Ecological Economics Vol. 68(6), pp. 1787-1796 |
article | DOI URL |
Abstract: We use data from a survey of 2401 households living along the Transamazon highway to study timber sales decisions of smallholders settling in Amazon native forests. We develop an econometric approach, to study both the decision to harvest timber and the volume of timber sold, that corrects for limited access to loggers leading to possible selection bias, incomplete labor markets, and differences in property rights regimes that characterize the area. We find that, irrespective of distance to markets, smallholders, that have either been settled by INCRA or have access to credit are more likely to sell wood, but those with outside income sources are less likely to sell. Higher timber prices decrease the likelihood of timber sales. The results suggest that timber sales are viewed only as a means for smallholders to reduce immediate cash constraints. With some exceptions these results hold across property rights regimes. (c) 2008 Published by Elsevier B.V. | |||||
BibTeX:
@article{amacher_smallholder_2009, author = {Amacher, Gregory S. and Merry, Frank D. and Bowman, Maria S.}, title = {Smallholder timber sale decisions on the Amazon frontier}, journal = {Ecological Economics}, year = {2009}, volume = {68}, number = {6}, pages = {1787--1796}, url = {://WOS:000265341600024 http://ac.els-cdn.com/S092180090800503X/1-s2.0-S092180090800503X-main.pdf?_tid=c11abf36-03f1-11e2-a196-00000aab0f26&acdnat=1348234943_779e71b03bfe0eb96c713d1fc763020b}, doi = {https://doi.org/10.1016/j.ecolecon.2008.11.018} } |
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Amacher, G.S. | Managing a global resource: Challenges of forest conservation and development [BibTeX] |
2006 | American Journal of Agricultural Economics Vol. 88(2), pp. 515-517 |
article | DOI URL |
BibTeX:
@article{amacher_managing_2006, author = {Amacher, G. S.}, title = {Managing a global resource: Challenges of forest conservation and development}, journal = {American Journal of Agricultural Economics}, year = {2006}, volume = {88}, number = {2}, pages = {515--517}, url = {://WOS:000236716200019 http://ajae.oxfordjournals.org/content/88/2/515.full.pdf}, doi = {https://doi.org/10.1111/j.1467-8276.2006.00876_1.x} } |
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Alves Senna, M.C., Costa, M.H. and Pires, G.F. | Vegetation-atmosphere-soil nutrient feedbacks in the Amazon for different deforestation scenarios | 2009 | Journal of Geophysical Research-Atmospheres Vol. 114(D4) |
article | DOI URL |
Abstract: In recent decades, large areas of the Amazon forest have been deforested and the rainforest's future may be dependent on climate and soil nutrient feedbacks associated with deforestation. This is a two-way biosphere-atmosphere interaction problem: the response of the regional climate system to the land cover varies with the forest growth, which, in turn, depends on climate and nutrient stress. Nutrient stress also varies with forest age, being most severe for young forests and declining as forests mature. Here we use a coupled climate-biosphere model to investigate how these feedbacks interact to control the secondary forest recovery after different deforestation scenarios, looking for a threshold of deforestation that could cause dangerous interference on the Amazon recovery. Results show that the reduction in rainfall is proportional to the amount of deforestation and is more drastic when the deforested area is higher than 40% of the original forest extent. In addition, this simulated precipitation reduction alone is not sufficient to prevent the rainforest regrowth. However, when the precipitation reduction is associated with a soil nutrient stress, a savannization process may start over southern Amazonia ( northern Mato Grosso state), no matter how much is deforested. In this region, a large precipitation reduction in the transition from the dry to the rainy season and an increase in the dry season duration are favorable to the savanna maintenance on nutrient-limited simulations. These results may be a valuable tool for prioritizing forest conservation in this region, which presently has the highest clearing rate in Amazonia. | |||||
BibTeX:
@article{alves_senna_vegetation-atmosphere-soil_2009, author = {Alves Senna, Monica Carneiro and Costa, Marcos Heil and Pires, Gabrielle Ferreira}, title = {Vegetation-atmosphere-soil nutrient feedbacks in the Amazon for different deforestation scenarios}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2009}, volume = {114}, number = {D4}, url = {://WOS:000263612200002 http://www.agu.org/journals/jd/jd0904/2008JD010401/2008JD010401.pdf}, doi = {https://doi.org/10.1029/2008jd010401} } |
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Alves Senna, M.C., Costa, M.H., Chipponelli Pinto, L.I., Acioli Imbuzeiro, H.M., Freitas Diniz, L.M. and Pires, G.F. | Vegetation Structure and Dynamics in Amazonia Using a Coupled Climate-Biosphere Model | 2009 | Earth Interactions Vol. 13(11), pp. 1-28 |
article | DOI URL |
Abstract: The Amazon rain forest constitutes one of the major global stocks of carbon. Recent studies, including the last Intergovernmental Panel on Climate Change report and the Coupled Climate Carbon Cycle Model Intercomparison Project, have suggested that it may reduce in size and lose biomass during the twenty-first century through a savannization process. A better understanding of how this ecosystem structure, dynamics, and carbon balance may respond to future climate changes is needed. This article investigates how well a fully coupled atmosphere-biosphere model can reproduce vegetation structure and dynamics in Amazonia to the extent permitted by available data. The accurate representation of the coupled climate-biosphere dynamics requires the accurate representation of climate, net primary production (NPP), and its partition among the several carbon pool components. The simulated climate is validated against precipitation (within 5% of four datasets) and incident solar radiation (within 7% of observations). The authors also validate (i) simulated land cover, which reproduces well the observed patterns; (ii) NPP, within 5% of observations; and (iii) respiration rates, within 15% of observations. The performance of simulated variables that depend on carbon allocation, like NPP partitioning, leaf area index, and aboveground live biomass, although good on a regional mean, is significantly low when spatial patterns are considered. These errors may be attributed to fixed carbon allocation and residence time parameters assumed by the model. Carbon allocation apparently varies spatially, and to simulate this spatial variability is quite a challenge. | |||||
BibTeX:
@article{alves_senna_vegetation_2009, author = {Alves Senna, Monica Carneiro and Costa, Marcos Heil and Chipponelli Pinto, Lucia Iracema and Acioli Imbuzeiro, Hewlley Maria and Freitas Diniz, Luciana Mara and Pires, Gabrielle Ferreira}, title = {Vegetation Structure and Dynamics in Amazonia Using a Coupled Climate-Biosphere Model}, journal = {Earth Interactions}, year = {2009}, volume = {13}, number = {11}, pages = {1--28}, url = {://WOS:000271090800002 http://journals.ametsoc.org/doi/pdf/10.1175/2009EI281.1}, doi = {https://doi.org/10.1175/2009ei281.1} } |
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Alves, N.d.O., Matos Loureiro, A.L., dos Santos, F.C., Nascimento, K.H., Dallacort, R., Vasconcellos, P.d.C., Hacon, S.d.S., Artaxo, P. and Batistuzzo de Medeiros, S.R. | Genotoxicity and composition of particulate matter from biomass burning in the eastern Brazilian Amazon region | 2011 | Ecotoxicology and Environmental Safety Vol. 74(5), pp. 1427-1433 |
article | DOI URL |
Abstract: In the present study Tradescantia pallida micronucleus (Trad-MCN) bioassay was used to assess the genotoxicity of particulate matter with a mass median aerodynamic diameter less than 10 pm (PM(10)) in Tangara da Serra (MT), a Brazilian Amazon region that suffers the impact of biomass burning. The levels of PM (coarse and fine size fractions) and black carbon (BC) collected were also measured. Furthermore, the alkanes and polycyclic aromatic hydrocarbons (PAHs) were identified and quantified in the samples taken during the burning period by gas chromatography with flame ionization detection (GC-FID). The PM and BC results for both fractions indicate a strong correlation (p textless 0.001). The analysis of alkanes indicates an anthropic influence. Retene was the most abundant PAH found, an indicator of biomass burning, and 12 other PAHs considered to be potentially mutagenic and/or carcinogenic were identified in this sample. The Trad-MCN bioassay showed a significant increase in micronucleus frequency during the period of most intense burning, possibly related to the mutagenic PAHs that were found in such extracts. This study demonstrated that Trad-MCN was sensitive and efficient in evaluating the genotoxicity of organic compounds from biomass burning. It further emphasizes the importance of performing chemical analysis, because changes in chemical composition generally have a negative effect on many living organisms. This bioassay (ex situ), using T. pallida with chemical analysis, is thus recommended for characterizing the genotoxicity of air pollution. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{alves_genotoxicity_2011, author = {Alves, Nilmara de Oliveira and Matos Loureiro, Ana Lucia and dos Santos, Fernando Cavalcante and Nascimento, Katia Halter and Dallacort, Rivanildo and Vasconcellos, Perola de Castro and Hacon, Sandra de Souza and Artaxo, Paulo and Batistuzzo de Medeiros, Silvia Regina}, title = {Genotoxicity and composition of particulate matter from biomass burning in the eastern Brazilian Amazon region}, journal = {Ecotoxicology and Environmental Safety}, year = {2011}, volume = {74}, number = {5}, pages = {1427--1433}, note = {Edition: 2011/04/19}, url = {://WOS:000291960600043 http://ac.els-cdn.com/S0147651311000911/1-s2.0-S0147651311000911-main.pdf?_tid=bc61a126-03f1-11e2-b374-00000aacb35e&acdnat=1348234935_628501f912530bac50272134403ca421}, doi = {https://doi.org/10.1016/j.ecoenv.2011.04.007} } |
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Alves, N.d.O., Galvao, M.F., Artaxo, P., Loureiro, A.L., Vasconcellos, P., Hacon, S. and Batistuzzo, S. | Analysis genotoxic and composition of organic particulate matter from biomass burning in Alta Floresta, a Brazilian Amazon region [BibTeX] |
2011 | Toxicology Letters Vol. 205, pp. S99-S100 |
article | DOI URL |
BibTeX:
@article{alves_analysis_2011, author = {Alves, Nilmara de Oliveira and Galvao, M. F. and Artaxo, P. and Loureiro, A. L. and Vasconcellos, P. and Hacon, S. and Batistuzzo, S.}, title = {Analysis genotoxic and composition of organic particulate matter from biomass burning in Alta Floresta, a Brazilian Amazon region}, journal = {Toxicology Letters}, year = {2011}, volume = {205}, pages = {S99--S100}, url = {://WOS:000293814500316 http://ac.els-cdn.com/S0378427411005625/1-s2.0-S0378427411005625-main.pdf?_tid=c6520aae-03f1-11e2-9d72-00000aab0f6c&acdnat=1348234952_c44070e0b48bac9039ac606807aabaff}, doi = {https://doi.org/10.1016/j.toxlet.2011.05.362} } |
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Alves, N.d.O., Brito, J., Caumo, S., Arana, A., Hacon, S.d.S., Artaxo, P., Hillamo, R., Teinilä, K., Medeiros, S.R.B.d. and Vasconcellos, P.d.C. | Biomass burning in the Amazon region: Aerosol source apportionment and associated health risk assessment [BibTeX] |
2015 | Atmospheric Environment Vol. 120, pp. 277-285 |
article | DOI |
BibTeX:
@article{alves_biomass_2015, author = {Alves, N. de O. and Brito, J. and Caumo, S. and Arana, A. and Hacon, S. de S. and Artaxo, P. and Hillamo, R. and Teinilä, K. and Medeiros, S. R. B. de and Vasconcellos, P. de C.}, title = {Biomass burning in the Amazon region: Aerosol source apportionment and associated health risk assessment}, journal = {Atmospheric Environment}, year = {2015}, volume = {120}, pages = {277--285}, note = {Edition: http://www.sciencedirect.com/science/article/pii/S1352231015303046}, doi = {https://doi.org/10.1016/j.atmosenv.2015.08.059} } |
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Alves, N.d.O., Batistuzzo, S., Artaxo, P., Loureiro, A.L., Vasconcellos, P. and Hacon, S. | Genotoxicity, quantification and composition of particulate matter from biomass burning in the eastern Brazilian Amazon region [BibTeX] |
2011 | Toxicology Letters Vol. 205, pp. S100-S100 |
article | DOI URL |
BibTeX:
@article{alves_genotoxicity_2011-1, author = {Alves, Nilmara de Oliveira and Batistuzzo, S. and Artaxo, P. and Loureiro, A. L. and Vasconcellos, P. and Hacon, S.}, title = {Genotoxicity, quantification and composition of particulate matter from biomass burning in the eastern Brazilian Amazon region}, journal = {Toxicology Letters}, year = {2011}, volume = {205}, pages = {S100--S100}, url = {://WOS:000293814500317 http://ac.els-cdn.com/S0378427411005637/1-s2.0-S0378427411005637-main.pdf?_tid=b9958b88-03f1-11e2-a1ac-00000aacb35e&acdnat=1348234931_6ea6ac2d9600ec532b3e7623db052d46}, doi = {https://doi.org/10.1016/j.toxlet.2011.05.363} } |
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Alves, M., L.A.T., P. and G.S.S.D., M. | Estudo da variabilidade da cobertura de nuvens altas na Amazônia Central [BibTeX] |
2007 | Acta Amazonica Vol. 37(1), pp. 71 - 80 |
article | |
BibTeX:
@article{alves_estudo_2007, author = {Alves, Machado, L.A.T., Prasad, G.S.S.D., M.A.S.}, title = {Estudo da variabilidade da cobertura de nuvens altas na Amazônia Central}, journal = {Acta Amazonica}, year = {2007}, volume = {37}, number = {1}, pages = {71 -- 80} } |
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Alves, L.M., Marengo, J.A., Fu, R. and Bombardi, R.J. | Sensitivity of Amazon Regional Climate to Deforestation [BibTeX] |
2017 | American Journal of Climate Change Vol. 6, pp. 75-98 |
article | |
BibTeX:
@article{alves_sensitivity_2017, author = {Alves, Lincoln Muniz and Marengo, Jose A. and Fu, Rong and Bombardi, Rodrigo J.}, title = {Sensitivity of Amazon Regional Climate to Deforestation}, journal = {American Journal of Climate Change}, year = {2017}, volume = {6}, pages = {75--98} } |
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Alves, L.M. and Marengo, J. | Assessment of regional seasonal predictability using the PRECIS regional climate modeling system over South America | 2010 | Theoretical and Applied Climatology Vol. 100(3-4), pp. 337-350 |
article | DOI URL |
Abstract: The purpose of this study was to evaluate the accuracy and skill of the UK Met Office Hadley Center Regional Climate Model (HadRM3P) in describing the seasonal variability of the main climatological features over South America and adjacent oceans, in long-term simulations (30 years, 1961-1990). The analysis was performed using seasonal averages from observed and simulated precipitation, temperature, and lower- and upper-level circulation. Precipitation and temperature patterns as well as the main general circulation features, including details captured by the model at finer scales than those resolved by the global model, were simulated by the model. However, in the regional model, there are still systematic errors which might be related to the physics of the model (convective schemes, topography, and land-surface processes) and the lateral boundary conditions and possible biases inherited from the global model. | |||||
BibTeX:
@article{alves_assessment_2010, author = {Alves, Lincoln M. and Marengo, Jose}, title = {Assessment of regional seasonal predictability using the PRECIS regional climate modeling system over South America}, journal = {Theoretical and Applied Climatology}, year = {2010}, volume = {100}, number = {3-4}, pages = {337--350}, url = {://WOS:000277098800008 http://www.springerlink.com/content/n91100k887275225/fulltext.pdf}, doi = {https://doi.org/10.1007/s00704-009-0165-2} } |
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Alves, K.S.d.S., Sanches, L., Andrade, N.L.R.d., Guariente, G.S.S. and Zeilhofer, P. | Estimation of rainfall based on remote sensing and observation fields in Jaru Biological Reserve at the Brazilian Amazonian forest [BibTeX] |
2021 | Theoretical and Applied Engineering Vol. 5, pp. 1-12 |
article | |
BibTeX:
@article{alves_estimation_2021, author = {Alves, Keylyane Santos da Silva and Sanches, Luciana and Andrade, Nara Luísa Reis de and Guariente, Gracyeli Santos Souza and Zeilhofer, Peter}, title = {Estimation of rainfall based on remote sensing and observation fields in Jaru Biological Reserve at the Brazilian Amazonian forest}, journal = {Theoretical and Applied Engineering}, year = {2021}, volume = {5}, pages = {1--12} } |
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Alves, F., Vendrame, G. and F.S.M., I.F. | Modificações do microclima e regime hidrológico devido ao desmatamento na Amazônia: estudo de um caso em Rondônia (RO), Brasil [BibTeX] |
1999 | Acta Amazonica Vol. 24(3), pp. 395-409 |
article | |
BibTeX:
@article{alves_modificacoes_1999, author = {Alves, Fisch, G., Vendrame, I.F., F.S.M.}, title = {Modificações do microclima e regime hidrológico devido ao desmatamento na Amazônia: estudo de um caso em Rondônia (RO), Brasil}, journal = {Acta Amazonica}, year = {1999}, volume = {24}, number = {3}, pages = {395--409} } |
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Alves, E.G., Tóta, J., Turnipseed, A., Guenther, A.B., Vega Bustillos, J.O.W., Santana, R.A., Cirino, G.G., Tavares, J.V., Lopes, A.P., Nelson, B.W., de Souza, R.A., Gu, D., Stavrakou, T., Adams, D.K., Wu, J., Saleska, S. and Manzi, A.O. | Leaf phenology as one important driver of seasonal changes in isoprene emissions in central Amazonia [BibTeX] |
2018 | Biogeosciences Vol. 15(13), pp. 4019-4032 |
article | DOI URL |
BibTeX:
@article{alves_leaf_2018, author = {Alves, E. G. and Tóta, J. and Turnipseed, A. and Guenther, A. B. and Vega Bustillos, J. O. W. and Santana, R. A. and Cirino, G. G. and Tavares, J. V. and Lopes, A. P. and Nelson, B. W. and de Souza, R. A. and Gu, D. and Stavrakou, T. and Adams, D. K. and Wu, J. and Saleska, S. and Manzi, A. O.}, title = {Leaf phenology as one important driver of seasonal changes in isoprene emissions in central Amazonia}, journal = {Biogeosciences}, year = {2018}, volume = {15}, number = {13}, pages = {4019--4032}, url = {https://bg.copernicus.org/articles/15/4019/2018/}, doi = {https://doi.org/10.5194/bg-15-4019-2018} } |
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Alves, E.G., Tóta, J., Turnipseed, A., Guenther, A.B., Bustillos, J.O.W.V., Santana, R.A., Cirino, G.G., Tavares, J.V., Lopes, A.P., Nelson, B.W., Souza, R.A.d., Gu, D., Stavrakou, T., Adams, D.K., Wu, J., Saleska, S. and Manzi, A.O. | Leaf phenology as one important driver of seasonal changes in isoprene emissions in central Amazonia [BibTeX] |
2018 | Biogeosciences Vol. 15(13), pp. 4019-4032 |
article | DOI |
BibTeX:
@article{alves_leaf_2018-1, author = {Alves, Eliane G. and Tóta, Julio and Turnipseed, Andrew and Guenther, Alex B. and Bustillos, José Oscar W. Vega and Santana, Raoni A. and Cirino, Glauber G. and Tavares, Julia V. and Lopes, Aline P. and Nelson, Bruce W. and Souza, Rodrigo A. de and Gu, Dasa and Stavrakou, Trissevgeni and Adams, David K. and Wu, Jin and Saleska, Scott and Manzi, Antonio O.}, title = {Leaf phenology as one important driver of seasonal changes in isoprene emissions in central Amazonia}, journal = {Biogeosciences}, year = {2018}, volume = {15}, number = {13}, pages = {4019--4032}, doi = {https://doi.org/10.5194/bg-15-4019-2018} } |
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Alves, E.G., Jardine, K., Tota, J., Jardine, A., Yãnez-Serrano, A.M., Karl, T., Tavares, J., Nelson, B., Gu, D., Stavrakou, T., Martin, S., Artaxo, P., Manzi, A. and Guenther, A. | Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia [BibTeX] |
2016 | Atmos. Chem. Phys. Vol. 16, pp. 3903-3925 |
article | |
BibTeX:
@article{alves_seasonality_2016, author = {Alves, Eliane G. and Jardine, Kolby and Tota, Julio and Jardine, Angela and Yãnez-Serrano, Ana Maria and Karl, Thomas and Tavares, Julia and Nelson, Bruce and Gu, Dasa and Stavrakou, Trissevgeni and Martin, Scot and Artaxo, Paulo and Manzi, Antonio and Guenther, Alex}, title = {Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia}, journal = {Atmos. Chem. Phys.}, year = {2016}, volume = {16}, pages = {3903--3925} } |
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Alves, E.G., Harley, P., Gonçalves, J.F.d.C., Moura, C.E.d.S. and Jardine, K. | Effects of light and temperature on isoprene emission at different leaf developmental stages of Eschweilera coriacea in central Amazon [BibTeX] |
2014 | Acta Amazonica Vol. 44(1), pp. 9 - 18 |
article | |
BibTeX:
@article{alves_effects_2014, author = {Alves, E. G. and Harley, P. and Gonçalves, J. F. de C. and Moura, C. E. da Silva and Jardine, K.}, title = {Effects of light and temperature on isoprene emission at different leaf developmental stages of Eschweilera coriacea in central Amazon}, journal = {Acta Amazonica}, year = {2014}, volume = {44}, number = {1}, pages = {9 -- 18} } |
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Alves, D.S., Pereira, J.L.G., De Sousa, C.L., Soares, J.V. and Yamaguchi, F. | Characterizing landscape changes in central Rondonia using Landsat TM imagery [BibTeX] |
1999 | International Journal of Remote Sensing Vol. 20(14), pp. 2877-2882 |
article | DOI URL |
BibTeX:
@article{alves_characterizing_1999, author = {Alves, D. S. and Pereira, J. L. G. and De Sousa, C. L. and Soares, J. V. and Yamaguchi, F.}, title = {Characterizing landscape changes in central Rondonia using Landsat TM imagery}, journal = {International Journal of Remote Sensing}, year = {1999}, volume = {20}, number = {14}, pages = {2877--2882}, url = {://WOS:000082505200012 http://www.tandfonline.com/doi/abs/10.1080/014311699211859}, doi = {https://doi.org/10.1080/014311699211859} } |
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Alves, D.S., Morton, D.C., Batistella, M., Roberts, D.A. and Souza Jr, C. | The Changing Rates and Patterns of Deforestation and Land Use in Brazilian Amazonia [BibTeX] |
2009 | Vol. 186Amazonia and Global Change, pp. 11-24 |
incollection | DOI URL |
BibTeX:
@incollection{keller_changing_2009, author = {Alves, Diogenes S. and Morton, Douglas C. and Batistella, Mateus and Roberts, Dar A. and Souza Jr, Carlos}, title = {The Changing Rates and Patterns of Deforestation and Land Use in Brazilian Amazonia}, booktitle = {Amazonia and Global Change}, publisher = {Geophys. Monogr. Ser.}, year = {2009}, volume = {186}, pages = {11--24}, url = {http://onlinelibrary.wiley.com/book/10.1029/GM186}, doi = {https://doi.org/10.1029/GM186} } |
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Alves, D.S., Escada, M.I.S., Pereira, J.L.G. and Linhares, C.D. | Land use intensification and abandonment in Rondonia, Brazilian Amazonia | 2003 | International Journal of Remote Sensing Vol. 24(4), pp. 899-903 |
article | DOI URL |
Abstract: An analysis of the evolution of deforestation and secondary vegetation in abandoned areas in a region of Rondonia was based on classifications of 1985 and 1995 Landsat Thematic Mapper images. Secondary vegetation corresponded to 28% of the deforested area in both years. Deforested area and secondary vegetation were calculated for 2.5 km x 2.5 km cells. During the period of study, deforestation tended to increase in cells that showed the highest fractions of deforestation in 1985, particularly near the region's main road, where forest clearing may have exceeded frequently the 50% legal limits in force in 1995. The relative importance of secondary vegetation tended to decrease in cells with more deforestation and,increased near the edge of the deforestation process, in newly settled areas. Concentration of deforestation and the concurrent decrease of secondary vegetation suggest a scenario of land use intensification based on pasture expansion, where abandonment and large patches of secondary vegetation become infrequent. | |||||
BibTeX:
@article{alves_land_2003, author = {Alves, D. S. and Escada, M. I. S. and Pereira, J. L. G. and Linhares, C. D.}, title = {Land use intensification and abandonment in Rondonia, Brazilian Amazonia}, journal = {International Journal of Remote Sensing}, year = {2003}, volume = {24}, number = {4}, pages = {899--903}, url = {://WOS:000181422100025 http://www.tandfonline.com/doi/abs/10.1080/0143116021000015807}, doi = {https://doi.org/10.1080/0143116021000015807} } |
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Alves, D.S., Batistella, M. and Moran, E.F. | A Questão das Dimensões Humanas no Experimento de Grande Escala da Biosfera-Atmosfera na Amazônia – LBA [BibTeX] |
2008 | Vol. 1(1)Amazônia: Natureza e Sociedade em Transformação, pp. 15-34 |
incollection | |
BibTeX:
@incollection{batistella_questao_2008, author = {Alves, D. S. and Batistella, M. and Moran, E. F.}, title = {A Questão das Dimensões Humanas no Experimento de Grande Escala da Biosfera-Atmosfera na Amazônia – LBA}, booktitle = {Amazônia: Natureza e Sociedade em Transformação}, publisher = {Editora Universidade de São Paulo}, year = {2008}, volume = {1}, number = {1}, pages = {15--34}, note = {Section: 1} } |
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Alves, D. | Taking things public: a contribution to address human dimensions of environmental change | 2008 | Philosophical Transactions of the Royal Society B-Biological Sciences Vol. 363(1498), pp. 1903-1909 |
article | DOI URL |
Abstract: This paper addresses the question of environmental change in Amazonia, by looking at the experiences of the large-scale biosphere-atmosphere (LBA) experiment in the Amazon, and three other enterprises-the extractive reserves, the Pilot Programme to Conserve the Brazilian Rain Forest (PPG7) and ecological-economic zoning-that address questions of sustainable development in the region. The LBA experience shows how the integration with the social sciences can be critical for science to explore its own outcomes for society, while the other programmes expose environmental change as a problem with too many intersections within society, so the outcomes of any initiative depends on placing it before a complex, tense and wide arena. | |||||
BibTeX:
@article{alves_taking_2008, author = {Alves, D.S.}, title = {Taking things public: a contribution to address human dimensions of environmental change}, journal = {Philosophical Transactions of the Royal Society B-Biological Sciences}, year = {2008}, volume = {363}, number = {1498}, pages = {1903--1909}, note = {Edition: 2008/02/13}, url = {://WOS:000254577500024 http://rstb.royalsocietypublishing.org/content/363/1498/1903.full.pdf}, doi = {https://doi.org/10.1098/rstb.2007.0020} } |
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Alves, D. | Science and technology and sustainable development in Brazilian Amazon | 2007 | Stability of Tropical Rainforest Margins: Linking Ecological, Economic and Social Constraints of Land Use and Conservation, pp. 493-512 | incollection | URL |
Abstract: Deforestation in the Brazilian Amazon increased from 10 million hectares in the 1970s to more than 60 million hectares at the turn of the century, resulting in growing awareness about deforestation impacts like greenhouse-gas emissions, loss of biodiversity, and motivating a number of initiatives involving the science and technology (S&T) field to address the issues of deforestation and sustainable development in the Amazon. The present work summarizes part of the large-scale land cover-use changes that occurred in the region and then analyses the organization of four S&T programs carried out in the Amazon in the context of alarming deforestation rates and rapidly changing land use in the Amazonian frontier. The four programs include two major research programs - the Large-Scale Biosphere-Atmosphere Experiment in the Amazon (LBA) and the Science & Technology Subprogram (S&T) of the Pilot Program to Conserve the Brazilian Rain Forest (PPG7) - and two examples of environmental monitoring and management - the Ecological-Economic Zoning (ZEE) and deforestation monitoring programs. In the context of high rates of forest loss and generally very weak institutions, the initiatives organized with the concourse of the S&T field may have significantly contributed to advance the discussions of sustainable development and sustainable land use in the frontier, and to mature some ideas about the participation of civil society, national environmental policy and, also, international cooperation. These exercises also suggest that the tasks of reducing and mitigating deforestation impacts and fostering sustainable land use are not to be engineered but, rather, negotiated, and that understanding how to contribute to such negotiations seems to be a major challenge for the science and technology field in Brazil. | |||||
BibTeX:
@incollection{tscharntke_science_2007, author = {Alves, D.S.}, title = {Science and technology and sustainable development in Brazilian Amazon}, booktitle = {Stability of Tropical Rainforest Margins: Linking Ecological, Economic and Social Constraints of Land Use and Conservation}, year = {2007}, pages = {493--512}, url = {://WOS:000248525000023} } |
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Alves, D.S. | Space-time dynamics of deforestation in Brazilian Amazonia | 2002 | International Journal of Remote Sensing Vol. 23(14), pp. 2903-2908 |
article | DOI URL |
Abstract: Deforestation maps derived from Landsat Multi-Spectral Scanner (MSS) and Thematic Mapper (TM) imagery were used to analyse spatial patterns of deforestation in the 1970s and the 1991-1997 period in Brazilian Legal Amazonia. Nearly 90% of the deforestation has occurred within 100 km from major roads established under federal development programmes. Clearings larger than 50 ha and 200 ha accounted, respectively, for 74% and 50% of the total deforestation in the 1991-1997 period. Results show that more intense deforestation has been concentrated over some regions, leading to the continuous enlargement of forest clearings and contributing to aggravate deforestation impacts in such areas. | |||||
BibTeX:
@article{alves_space-time_2002, author = {Alves, D. S.}, title = {Space-time dynamics of deforestation in Brazilian Amazonia}, journal = {International Journal of Remote Sensing}, year = {2002}, volume = {23}, number = {14}, pages = {2903--2908}, url = {://WOS:000176948800011 http://www.tandfonline.com/doi/abs/10.1080/01431160110096791}, doi = {https://doi.org/10.1080/01431160110096791} } |
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Alves de Oliveira, B.F., Ignotti, E. and Hacon, S.S. | A systematic review of the physical and chemical characteristics of pollutants from biomass burning and combustion of fossil fuels and health effects in Brazil | 2011 | Cadernos De Saude Publica Vol. 27(9), pp. 1678-1698 |
article | URL |
Abstract: The aim of this study was to carry out a review of scientific literature published in Brazil between 2000 and 2009 on the characteristics of air pollutants from different emission sources, especially particulate matter (PM) and its effects on respiratory health. Using electronic databases, a systematic literature review was performed of all research related to air pollutant emissions. Publications were analyzed to identify the physical and chemical characteristics of pollutants from different emission sources and their related effects on the respiratory system. The PM(2.5) is composed predominantly of organic compounds with 20% of inorganic elements. Higher concentrations of metals were detected in metropolitan areas than in biomass burning regions. The relative risk of hospital admissions due to respiratory diseases in children was higher than in the elderly population. The results of studies of health effects of air pollution are specific to the region where the emissions occurred and should not be used to depict the situation in other areas with different emission sources. | |||||
BibTeX:
@article{alves_de_oliveira_systematic_2011, author = {Alves de Oliveira, Beatriz Fatima and Ignotti, Eliane and Hacon, Sandra S.}, title = {A systematic review of the physical and chemical characteristics of pollutants from biomass burning and combustion of fossil fuels and health effects in Brazil}, journal = {Cadernos De Saude Publica}, year = {2011}, volume = {27}, number = {9}, pages = {1678--1698}, url = {://WOS:000295723800003} } |
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Alvala, R.C.S., Gielow, R., da Rocha, H.R., Freitas, H.C., Lopes, J.M., Manzi, A.O., von Randow, C., Dias, M., Cabral, O.M.R. and Waterloo, M.J. | Intradiurnal and seasonal variability of soil temperature, heat flux, soil moisture content, and thermal properties under forest and pasture in Rondonia | 2002 | Journal of Geophysical Research-Atmospheres Vol. 107(D20) |
article | DOI URL |
Abstract: Soil temperatures depend on the soil heat flux, an important parameter in meteorological and plant growth-energy balance models. Thus, they were measured, together with soil moisture contents, within the LBA program at forest (Reserva Jaru) and pasture (Fazenda Nossa Senhora) sites in Rondonia, Brazilian Amazonia during wet (February) and dry (August) periods of 1999. The wet period showed maxima of the heat flux into the soil around five to six times smaller at the forest than at the pasture, except for some spikes that are related to stronger solar forcing, such as those due to sunspecks in the forest. This pattern remained during the dry period, but with doubled maximum values. Also, the soil heat flux and the soil temperatures responded very significantly to the passage of cold fronts in both periods at both sites. Temperature profiles measured in the 0.10-0.40 m soil layer showed daily averages and ranges smaller at the forest than at the pasture. The daily average of the soil moisture content in the same layer, during the wet season, increased with depth at both sites, with consistently lower values at the forest. However, their ranges were smaller at the pasture, except for the 0.40 m depth. During the dry period, these ranges were much higher at the pasture, but with nearer average values. Finally, the computed daily apparent soil thermal diffusivities, volumetric heat contents, and thermal conductivities are presented, with the first ones crossed with the measured soil moisture content. | |||||
BibTeX:
@article{alvala_intradiurnal_2002, author = {Alvala, R. C. S. and Gielow, R. and da Rocha, H. R. and Freitas, H. C. and Lopes, J. M. and Manzi, A. O. and von Randow, C. and Dias, Mafs and Cabral, O. M. R. and Waterloo, M. J.}, title = {Intradiurnal and seasonal variability of soil temperature, heat flux, soil moisture content, and thermal properties under forest and pasture in Rondonia}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2002}, volume = {107}, number = {D20}, url = {://WOS:000180367300002 http://www.agu.org/journals/jd/jd0216/2001JD000599/2001JD000599.pdf}, doi = {https://doi.org/10.1029/2001jd000599} } |
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Alsdorf, D.E., Melack, J.M., Dunne, T., Mertes, L.A.K., Hess, L.L. and Smith, L.C. | Interferometric radar measurements of water level changes on the Amazon flood plain | 2000 | Nature Vol. 404(6774), pp. 174-177 |
article | DOI URL |
Abstract: Measurements of water levels in the main channels of rivers, upland tributaries and floodplain lakes are necessary for understanding flooding hazards, methane production, sediment transport and nutrient exchange. But most remote river basins have only a few gauging stations and these tend to be restricted to large river channels. Although radar remote sensing techniques using interferometric phase measurements have the potential to greatly improve spatial sampling, the phase is temporally incoherent over open water and has therefore not been used to determine water levels. Here we use interferometric synthetic aperture radar (SAR) data(1-3), acquired over the central Amazon by the Space Shuttle imaging radar mission(4), to measure subtle water level changes in an area of flooded vegetation on the Amazon flood plain. The technique makes use of the fact that flooded forests and floodplain lakes with emergent shrubs permit radar double-bounce returns from water and vegetation surfaces(5,6), thus allowing coherence to be maintained. Our interferometric phase observations show decreases in water levels of 7-11 cm per day for tributaries and lakes within similar to 20 km of a main channel and 2-5 cm per day at distances of similar to 80 km. Proximal floodplain observations are in close agreement with main-channel gauge records, indicating a rapid response of the flood plain to decreases in river stage. With additional data from future satellite missions, the technique described here should provide direct observations important for understanding flood dynamics and hydrologic exchange between rivers and flood plains. | |||||
BibTeX:
@article{alsdorf_interferometric_2000, author = {Alsdorf, D. E. and Melack, J. M. and Dunne, T. and Mertes, L. A. K. and Hess, L. L. and Smith, L. C.}, title = {Interferometric radar measurements of water level changes on the Amazon flood plain}, journal = {Nature}, year = {2000}, volume = {404}, number = {6774}, pages = {174--177}, note = {Edition: 2000/03/21}, url = {://WOS:000085870900048 http://www.nature.com/nature/journal/v404/n6774/pdf/404174a0.pdf}, doi = {https://doi.org/10.1038/35004560} } |
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Alsdorf, D., Han, S.-C., Bates, P. and Melack, J. | Seasonal water storage on the Amazon floodplain measured from satellites | 2010 | Remote Sensing of Environment Vol. 114(11), pp. 2448-2456 |
article | DOI URL |
Abstract: The amount of water stored and moving through the Amazon floodplain is not known, yet is necessary for understanding the role of the wetland in the regional carbon balance and the sediment and nutrient exchanged with the main river channel. Here, we separate the Amazon floodplain into six 330 km x 330 km areas and use gravimetric and imaging satellite methods (i.e., GRACE, SRTM, GPCP and JERS-1) to estimate the amounts of water filling and draining from the mainstem Amazon floodplain. We show that the amount of water stored on and subsequently drained from the mainstem Amazon floodplain each year represents about 5% of the total volume of water discharged from the Amazon River into the Atlantic Ocean. Despite a five-fold increase in mainstem discharge from upstream to downstream, the floodplain water volume exchanged with the river only doubles (based on all six 330 km reach lengths). Rates of exchange along the 330 km reach lengths vary from 5500 m(3)/s during floodplain infilling to -7500 m(3)/s during drainage. The contribution to the floodplain from local upland runoff represents less than 20% of the floodplain water volume for any given time. (C) 2010 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{alsdorf_seasonal_2010, author = {Alsdorf, Douglas and Han, Shin-Chan and Bates, Paul and Melack, John}, title = {Seasonal water storage on the Amazon floodplain measured from satellites}, journal = {Remote Sensing of Environment}, year = {2010}, volume = {114}, number = {11}, pages = {2448--2456}, url = {://WOS:000282242000006 http://ac.els-cdn.com/S0034425710001768/1-s2.0-S0034425710001768-main.pdf?_tid=aead60a6-03f1-11e2-a982-00000aacb35f&acdnat=1348234912_a1f1bd14e001b53b4aad9f33bc25d2fb}, doi = {https://doi.org/10.1016/j.rse.2010.05.020} } |
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Alsdorf, D., Dunne, T., Melack, J., Smith, L. and Hess, L. | Diffusion modeling of recessional flow on central Amazonian floodplains | 2005 | Geophysical Research Letters Vol. 32(21) |
article | DOI URL |
Abstract: We present a continuity-based approach for calculating flow delivered to a main channel from an adjacent floodplain and use the values in a linear diffusion model to generalize fluxes across a floodplain. Using interferometric synthetic aperture radar (SAR) measurements of floodplain water level changes and the continuity equation, we demonstrate that flow rates are not the same throughout Amazonian floodplains. Also, rates of floodplain storage change are found to be least in areas of greatest distance from a main channel which suggests a long residence time. Linear diffusion modeling of floodplain drainage represents the composite behavior of flow through channels, swamps and lakes and provides a simple method of defining storage changes. The key parameter necessary for diffusion modeling is floodplain conductivity which can be constrained by a simple description of floodplain topography and measurements of temporal changes in floodplain water levels. | |||||
BibTeX:
@article{alsdorf_diffusion_2005, author = {Alsdorf, D. and Dunne, T. and Melack, J. and Smith, L. and Hess, L.}, title = {Diffusion modeling of recessional flow on central Amazonian floodplains}, journal = {Geophysical Research Letters}, year = {2005}, volume = {32}, number = {21}, url = {://WOS:000233159900008 http://www.agu.org/pubs/crossref/2005/2005GL024412.shtml}, doi = {https://doi.org/10.1029/2005gl024412} } |
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Alsdorf, D., Birkett, C., Dunne, T., Melack, J. and Hess, L. | Water level changes in a large Amazon lake measured with spaceborne radar interferometry and altimetry | 2001 | Geophysical Research Letters Vol. 28(14), pp. 2671-2674 |
article | DOI URL |
Abstract: We demonstrate that interferometric processing of JERS-1 SAR data over an Amazon lake containing similar to 1500 islands yields centimeter-scale changes in the height of the water surface from February 14 to March 30, 1997. For the method to work, we qualitatively find that inundation of about one or two leafless trees per 25 m(2) multi-look SAR pixel is sufficient to return the radar pulse to the side-looking antenna. Validation is provided by multi-temporal TOPEX-POSEIDON altimetry profiles, which directly measure surface heights relative to a fixed datum. Because SAR provides an image, the water height changes (similar to 12 cm) can be converted to a net volume measurement (280 million m(3)) over the 44 days separating the JERS-1 acquisitions. Compared to historical gauge records, removal of this volume from the lake required a similar to 50% greater flow. | |||||
BibTeX:
@article{alsdorf_water_2001, author = {Alsdorf, D. and Birkett, C. and Dunne, T. and Melack, J. and Hess, L.}, title = {Water level changes in a large Amazon lake measured with spaceborne radar interferometry and altimetry}, journal = {Geophysical Research Letters}, year = {2001}, volume = {28}, number = {14}, pages = {2671--2674}, url = {://WOS:000169849500001 http://www.agu.org/pubs/crossref/2001/2001GL012962.shtml}, doi = {https://doi.org/10.1029/2001gl012962} } |
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Alsdorf, D., Bates, P., Melack, J., Wilson, M. and Dunne, T. | Spatial and temporal complexity of the Amazon flood measured from space | 2007 | Geophysical Research Letters Vol. 34(8) |
article | DOI URL |
Abstract: Floodplain processes are driven by water flows that seasonally change in direction and consist of a myriad of interacting streams of varying depth, velocity, source, sediment concentration and chemistry. Here we show, using spaceborne interferometric synthetic aperture radar (SAR) JERS-1 measurements, the first spatially dense hydraulic mapping of the passage of a flood wave through a large, topographically complex floodplain. We find that temporal changes in flood water heights(partial derivative h/partial derivative t) are more complex than typically assumed. During the passage of a flood wave, sharp variations in partial derivative h/partial derivative t are localized along some floodplain channels. These channels separate adjacent locations with different rates of infilling. Near the peak of the flood wave, some of the channels are no longer evident as controls on partial derivative h/partial derivative t. During the passage of the flood wave, flow paths change from bathymetrically influenced to hydraulically controlled ( and back again), thus it is difficult to know the flow path a-priori from bathymetry alone. | |||||
BibTeX:
@article{alsdorf_spatial_2007, author = {Alsdorf, Doug and Bates, Paul and Melack, John and Wilson, Matt and Dunne, Thomas}, title = {Spatial and temporal complexity of the Amazon flood measured from space}, journal = {Geophysical Research Letters}, year = {2007}, volume = {34}, number = {8}, url = {://WOS:000245951100003 http://www.agu.org/pubs/crossref/2007/2007GL029447.shtml}, doi = {https://doi.org/10.1029/2007gl029447} } |
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Almeida, R., Silva, R., da Costa, A., Ferreira, L., Meir, P. and Ellison, A. | Induced drought strongly affects richness and composition of ground-dwelling ants in the eastern Amazon | 2023 | Oecologia Vol. 201(2), pp. 299-309 |
article | DOI URL |
Abstract: Species loss in tropical regions is forecast to occur under environmental change scenarios of low precipitation. One of the main questions is how drought will affect invertebrates, a key group for ecosystem functioning. We use 1 year of data from a long-term rainwater exclusion experiment in primary Amazonian rainforest to test whether induced water stress and covarying changes in soil moisture, soil respiration, and tree species richness, diversity, size, and total biomass affected species richness and composition (relative abundance) of ground-dwelling ants. Data on ant abundance and environmental variables were collected at two sites (control and experimental) in the Eastern Amazon. Since 2002, drought has been induced in the experimental plot by excluding 50% of normal rainfall. Ant species richness in the experiment plot was reduced and some generalist species responded positively. Ant species richness also increased in the experimental plot with increasing diversity of the plant species of the leaf litter. The relative abundance of ants differed between plots. The experimental plot was characterized by a higher frequency of generalist and other species that appeared to be favored by the reduction in rainfall. Between-plot comparisons suggested loss and changes in ant species composition in tropical forests were affected by increasing dryness. These changes could ultimately lead to cascading effects on ecosystem processes and the services they mediate. | |||||
BibTeX:
@article{almeida_induced_2023, author = {Almeida, R.P.S. and Silva, R.R. and da Costa, A.C.L. and Ferreira, L.V. and Meir, P. and Ellison, A.M.}, title = {Induced drought strongly affects richness and composition of ground-dwelling ants in the eastern Amazon}, journal = {Oecologia}, year = {2023}, volume = {201}, number = {2}, pages = {299--309}, note = {Edition: 2023/01/17}, url = {https://www.ncbi.nlm.nih.gov/pubmed/36645473}, doi = {https://doi.org/10.1007/s00442-023-05316-x} } |
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Almeida, R. and Shimabukuro, Y.E. | Monitoring biomass burning in the Brazilian Amazonia [BibTeX] |
2004 | International Journal of Remote Sensing Vol. 25(24), pp. 5537-5542 |
article | DOI URL |
BibTeX:
@article{almeida_monitoring_2004, author = {Almeida, R. and Shimabukuro, Y. E.}, title = {Monitoring biomass burning in the Brazilian Amazonia}, journal = {International Journal of Remote Sensing}, year = {2004}, volume = {25}, number = {24}, pages = {5537--5542}, url = {://WOS:000225687200001 http://www.tandfonline.com/doi/abs/10.1080/0143116031000075143}, doi = {https://doi.org/10.1080/0143116031000075143} } |
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Almeida, R., Roskenqvist, A., Shimabukuro, Y.E. and dos Santos, J.R. | Evaluation and perspectives of using multitemporal L-band SAR data to monitor deforestation in the Brazilian Amazonia | 2005 | Ieee Geoscience and Remote Sensing Letters Vol. 2(4), pp. 409-412 |
article | DOI URL |
Abstract: Japanese Earth Resources Satellite 1 (JERS-1) synthetic aperature radar (SAR) data were evaluated to map areas of deforestation in a Brazilian Amazonia test-site. The results were compared with information derived from a Landsat (TM) multitemporal series. Unambiguous detection of deforested areas was observed only when the entire deforestation process (slash, burning, and terrain clearing) had already occurred. This result recommends further investigations on the effectiveness of horizontal polarization SAR data to map deforestation in a consistent basis. The cross-polarized (horizontal-vertical) channel designed to be in the ALOS/PALSAR system is expected to improve the distinction between forested and recently deforested areas. | |||||
BibTeX:
@article{almeida_evaluation_2005, author = {Almeida, R. and Roskenqvist, A. and Shimabukuro, Y. E. and dos Santos, J. R.}, title = {Evaluation and perspectives of using multitemporal L-band SAR data to monitor deforestation in the Brazilian Amazonia}, journal = {Ieee Geoscience and Remote Sensing Letters}, year = {2005}, volume = {2}, number = {4}, pages = {409--412}, url = {://WOS:000232897100008 http://ieeexplore.ieee.org/ielx5/8859/32554/01522211.pdf?tp=&arnumber=1522211&isnumber=32554}, doi = {https://doi.org/10.1109/lgrs.2005.856679} } |
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Almeida, M.E., de Souza, R.A., Godoi R. H. M., G.P. and Santana | Aircraf observation of the ineraction of the Manaus plume with aerosol forest during rainy season: a case study [BibTeX] |
2016 | Ciência e Natura Vol. 38, pp. 510-516 |
article | |
BibTeX:
@article{almeida_aircraf_2016, author = {Almeida, M. E. ; de Souza, Rodrigo A.F. ; Godoi R. H. M., G. P. ; Santana}, title = {Aircraf observation of the ineraction of the Manaus plume with aerosol forest during rainy season: a case study}, journal = {Ciência e Natura}, year = {2016}, volume = {38}, pages = {510--516} } |
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Almeida, E., Rodrigues, D. and Luizão, F. | Produção de serrapilheira de florestas intactas e exploradas seletivamente no sul da Amazônia em função da área basal da vegetação e da densidade de plantas [BibTeX] |
2015 | Acta Amazonica Vol. 45(2) |
article | DOI |
BibTeX:
@article{almeida_producao_2015, author = {Almeida, E.J. and Rodrigues, D.J. and Luizão, F.J.}, title = {Produção de serrapilheira de florestas intactas e exploradas seletivamente no sul da Amazônia em função da área basal da vegetação e da densidade de plantas}, journal = {Acta Amazonica}, year = {2015}, volume = {45}, number = {2}, doi = {https://doi.org/10.1590/1809-4392201402543} } |
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Almeida, D.R.A.d., Stark, S.C., Shao, G., Schietti, J., Nelson, B.W., Silva, C.A., Gorgens, E.B., Valbuena, R., Papa, D.d.A. and Brancalion, P.H.S. | Optimizing the Remote Detection of Tropical Rainforest Structure with Airborne Lidar: Leaf Area Profile Sensitivity to Pulse Density and Spatial Sampling [BibTeX] |
2019 | Remote Sensing Vol. 11, pp. 92 |
article | |
BibTeX:
@article{almeida_optimizing_2019, author = {Almeida, D. R. A. de and Stark, S. C. and Shao, G. and Schietti, J. and Nelson, Bruce Walker and Silva, Carlos Alberto and Gorgens, Eric Bastos and Valbuena, Ruben and Papa, Daniel de Almeida and Brancalion, Pedro Henrique Santin}, title = {Optimizing the Remote Detection of Tropical Rainforest Structure with Airborne Lidar: Leaf Area Profile Sensitivity to Pulse Density and Spatial Sampling}, journal = {Remote Sensing}, year = {2019}, volume = {11}, pages = {92} } |
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Almeida, D.R.A., Stark, S.C., Schietti, J., Camargo, J.L.C., Amazonas, N.T., Gorgens, E.B., Rosa, D.M., Smith, M.N., Valbuena, R., Saleska, S., Andrade, A., Mesquita, R., Laurance, S.G., Laurance, W.F., Lovejoy, T.E., Broadbent, E.N., Shimabukuro, Y.E., Parker, G.G., Lefsky, M., Silva, C.A. and Brancalion, P.H.S. | Persistent effects of fragmentation on tropical rainforest canopy structure after 20 years of isolation [BibTeX] |
2019 | Ecological Applications Vol. 29(6), pp. e01952 |
article | DOI |
BibTeX:
@article{almeida_persistent_2019, author = {Almeida, D. R. A and Stark, S. C. and Schietti, J. and Camargo, J. L. C. and Amazonas, N. T. and Gorgens, E. B. and Rosa, D. M and Smith, M. N. and Valbuena, R. and Saleska, S. and Andrade, A. and Mesquita, R. and Laurance, S. G and Laurance, W. F. and Lovejoy, T. E and Broadbent, E. N. and Shimabukuro, Y. E. and Parker, G. G. and Lefsky, M. and Silva, C. A. and Brancalion, P. H. S}, title = {Persistent effects of fragmentation on tropical rainforest canopy structure after 20 years of isolation}, journal = {Ecological Applications}, year = {2019}, volume = {29}, number = {6}, pages = {e01952}, doi = {https://doi.org/10.1002/eap.1952} } |
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Almeida, C., Silva, M., Lobo, F.d.L., Farias, T.P., Gomes, A., Costa, L.C. and Escada, M.I.S. | TerraClass: classificação dos padrões de uso e cobertura da terra da Amazônia Legal [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 137-148 |
incollection | |
BibTeX:
@incollection{emilio_terraclass_2014, author = {Almeida, Cláudio and Silva, Maurício and Lobo, Felipe de Lucia and Farias, Taise Pinheiro and Gomes, Alessandra and Costa, Lidiane Cristina and Escada, Maria Isabel Sobral}, title = {TerraClass: classificação dos padrões de uso e cobertura da terra da Amazônia Legal}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {137--148}, note = {Section: 12} } |
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Almeida, A.S.d., Vieira, I.C.G., Nazaré, M., Barros, R. and Rocha, D.d.P.N.d. | Áreas de endemismo Belém e Xingu: configuração e espacialização do uso da terra e da cobertura vegetal [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 57-66 |
incollection | |
BibTeX:
@incollection{emilio_areas_2014, author = {Almeida, Arlete Silva de and Vieira, Ima Célia Guimarães and Nazaré, Márcia and Barros, Rodrigues and Rocha, Danusa di Paula Nascimento da}, title = {Áreas de endemismo Belém e Xingu: configuração e espacialização do uso da terra e da cobertura vegetal}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {57--66}, note = {Section: 5} } |
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Almeida, A.S., Stone, T.A., Vieira, I.C.G. and Davidson, E.A. | Nonfrontier Deforestation in the Eastern Amazon | 2010 | Earth Interactions Vol. 14 |
article | DOI URL |
Abstract: While interest in Amazonian deforestation mostly focuses on frontier areas, the amount of forest cover in areas already dominated by human settlement is also changing. Secondary forests play an increasingly important role for maintaining genetic diversity, hydrological functioning, and greenhouse gas emissions of altered landscapes, but secondary forests are also being converted to more intensive agricultural uses. Five dates of Landsat imagery from 1984 to 2002 were analyzed, covering 8000 km(2) of the Zona Bragantina of the eastern part of the Brazilian state of Para, which underwent its most intensive wave of deforestation several decades ago. However, even in this area of relatively found, both in the small remaining areas of mature forest and in the more widespread areas of secondary forests, as human population increased and land use intensified. Although there was an initial increase in the area of secondary forest from 1984 to 1994, there has been a steady decline since then, from 75% secondary forest cover in 1994 to 54% in 2002. The amount of pasture was relatively stable from 1984 to 1994 but more recently has shown a steady increase, reaching 37% cover in 2002. The average rate of carbon loss over the 18-yr study period was 0.9 Mg C ha(-1) yr(-1) for the 8000 km(2) study area. Forests in this long-settled region of eastern Amazonia continue to be degraded, resulting in the loss of ecosystem services and carbon stocks due to continued land-use change. | |||||
BibTeX:
@article{almeida_nonfrontier_2010, author = {Almeida, Arlete Silva and Stone, Thomas A. and Vieira, Ima Celia G. and Davidson, Eric A.}, title = {Nonfrontier Deforestation in the Eastern Amazon}, journal = {Earth Interactions}, year = {2010}, volume = {14}, url = {://WOS:000273886100001 http://journals.ametsoc.org/doi/abs/10.1175/2009EI290.1}, doi = {https://doi.org/10.1175/2009ei290.1} } |
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Alin, S.R., Rasera, M.d.F.F.L., Salimon, C.I., Richey, J.E., Holtgrieve, G.W., Krusche, A.V. and Snidvongs, A. | Physical controls on carbon dioxide transfer velocity and flux in low-gradient river systems and implications for regional carbon budgets | 2011 | Journal of Geophysical Research-Biogeosciences Vol. 116 |
article | DOI URL |
Abstract: Outgassing of carbon dioxide (CO(2)) from rivers and streams to the atmosphere is a major loss term in the coupled terrestrial-aquatic carbon cycle of major low-gradient river systems (the term "river system" encompasses the rivers and streams of all sizes that compose the drainage network in a river basin). However, the magnitude and controls on this important carbon flux are not well quantified. We measured carbon dioxide flux rates (F(CO2)), gas transfer velocity (k), and partial pressures (p(CO2)) in rivers and streams of the Amazon and Mekong river systems in South America and Southeast Asia, respectively. F(CO2) and k values were significantly higher in small rivers and streams (channels textless100 m wide) than in large rivers (channels textgreater100 m wide). Small rivers and streams also had substantially higher variability in k values than large rivers. Observed F(CO2) and k values suggest that previous estimates of basinwide CO(2) evasion from tropical rivers and wetlands have been conservative and are likely to be revised upward substantially in the future. Data from the present study combined with data compiled from the literature collectively suggest that the physical control of gas exchange velocities and fluxes in low-gradient river systems makes a transition from the dominance of wind control at the largest spatial scales (in estuaries and river mainstems) toward increasing importance of water current velocity and depth at progressively smaller channel dimensions upstream. These results highlight the importance of incorporating scale-appropriate k values into basinwide models of whole ecosystem carbon balance. | |||||
BibTeX:
@article{alin_physical_2011, author = {Alin, Simone R. and Rasera, Maria de Fatima F. L. and Salimon, Cleber I. and Richey, Jeffrey E. and Holtgrieve, Gordon W. and Krusche, Alex V. and Snidvongs, Anond}, title = {Physical controls on carbon dioxide transfer velocity and flux in low-gradient river systems and implications for regional carbon budgets}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2011}, volume = {116}, url = {://WOS:000286760300004 http://www.agu.org/pubs/crossref/2011/2010JG001398.shtml}, doi = {https://doi.org/10.1029/2010jg001398} } |
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Ali, A., Xu, C., Rogers, A., Fisher, R., Wullschleger, S., McDowell, N., Massoud, E., Vrugt, J., Muss, J., Fisher, J., Reich, P. and Wilson, C. | A global mechanistic model of plant photosynthesic capacity [BibTeX] |
2016 | Geoscientific Model Development Vol. 9(2), pp. 587606 |
article | |
BibTeX:
@article{ali_global_2016, author = {Ali, A. and Xu, C. and Rogers, A. and Fisher, R. and Wullschleger, S.D. and McDowell, N.G. and Massoud, E. and Vrugt, J.A. and Muss, J. and Fisher, J. and Reich, P.P. and Wilson, C.J.}, title = {A global mechanistic model of plant photosynthesic capacity}, journal = {Geoscientific Model Development}, year = {2016}, volume = {9}, number = {2}, pages = {587606} } |
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Alfaia, S.S., Ribeiro, G.A., Nobre, A.D., Luizao, R.C. and Luizao, F.J. | Evaluation of soil fertility in smallholder agroforestry systems and pastures in western Amazonia | 2004 | Agriculture Ecosystems & Environment Vol. 102(3), pp. 409-414 |
article | DOI URL |
Abstract: Agroforestry systems are often mentioned as a type of sustainable agriculture that is appropriate for the edapho-climatic conditions of Amazonia. However, long-term studies on the sustainability of this land use do not exist. This study evaluates the soil fertility in smallholder agroforestry systems in Western Amazonia, and compares the fertility of land under agroforestry with the fertility of neighboring land under pasture and native forest. Smallholdings located in Nova California, Rondonia, Brazil, were selected, with two different soil types. Soil pH, organic C, P, K, Ca, Mg and Al were determined. The soils of the agroforestry system maintained their improved chemical characteristics that originated in the burn, especially with respect to increased levels of exchangeable Ca and Mg and reduction of exchangeable Al, while maintaining stable levels of organic C, even when compared to adjacent primary forest soils. However, in the agroforestry system K and P fell to extremely low levels, below those considered to be critical for Amazonian soils. This reduction can reasonably be attributed to nutrient exports by consecutive harvests of cupuassu (Theobroma grandiflorum, Sterculiaceae) and pejibaye (Bactris gasipaes, Palmae) fruits. These nutrients can limit sustainable fruit yields in the agroforestry systems. (C) 2003 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{alfaia_evaluation_2004, author = {Alfaia, S. S. and Ribeiro, G. A. and Nobre, A. D. and Luizao, R. C. and Luizao, F. J.}, title = {Evaluation of soil fertility in smallholder agroforestry systems and pastures in western Amazonia}, journal = {Agriculture Ecosystems & Environment}, year = {2004}, volume = {102}, number = {3}, pages = {409--414}, url = {://WOS:000220873500014 http://ac.els-cdn.com/S0167880903003153/1-s2.0-S0167880903003153-main.pdf?_tid=aa53bae6-03f1-11e2-a1ac-00000aacb35e&acdnat=1348234906_36c038793158db929e5591de5bc942e3}, doi = {https://doi.org/10.1016/j.agee.2003.08.011} } |
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Alencar, A.A.C., Solorzano, L.A. and Nepstad, D.C. | Modeling forest understory fires in an eastern Amazonian landscape | 2004 | Ecological Applications Vol. 14(4), pp. S139-S149 |
article | URL |
Abstract: Forest understory fires are an increasingly important cause of forest impoverishment in Amazonia, but little is known of the landscape characteristics and climatic phenomena that determine their occurrence. We developed empirical functions relating the occurrence of understory forest fires to landscape features near Paragominas, a 35-yr-old ranching and logging center in eastern Amazonia. An historical sequence of maps of forest understory fire was created based on field interviews with local farmers and Landsat TM images. Several landscape features that might explain spatial variation in the occurrence of understory fires were also mapped and co-registered for each of the sample dates, including: forest fragment size and shape, forest impoverishment through logging and understory fire, sources of ignition (settlements and charcoal pits), roads, forest edges, and others. The spatial relationship between forest understory fire and each landscape characteristic was tested by regression analyses. Fire probability models were then developed for various combinations of landscape characteristics. The analyses were conducted separately for years of the El Nino Southern Oscillation (ENSO), which are associated with severe drought in eastern Amazonia, and non-ENSO years. Most (91%) of the forest area that burned during the 10-yr sequence caught fire during ENSO years, when severe drought may have increased both forest flammability and the escape of agricultural management fires. Forest understory fires were associated with forest edges, as reported in previous studies from Amazonia. But the strongest predictor of forest fire was the percentage of the forest fragment that had been previously logged or burned. Forest fragment size, distance to charcoal pits, distance to agricultural settlements, proximity to forest edge, and distance to roads were also correlated with forest understory fire. Logistic regression models using information on fragment degradation and distance to ignition sources accurately predicted the location of textgreater80% of the forest fires observed during the ENSO event of 1997-1998. In this Amazon landscape, forest understory fire is a complex function of several variables that influence both the flammability and ignition exposure of the forest. | |||||
BibTeX:
@article{alencar_modeling_2004, author = {Alencar, A. A. C. and Solorzano, L. A. and Nepstad, D. C.}, title = {Modeling forest understory fires in an eastern Amazonian landscape}, journal = {Ecological Applications}, year = {2004}, volume = {14}, number = {4}, pages = {S139--S149}, url = {://WOS:000223269000013} } |
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Alencar, A., Nepstad, D. and Vera Diaz, M.d.C. | Forest understory fire in the Brazilian Amazon in ENSO and non-ENSO years: Area burned and committed carbon emissions | 2006 | Earth Interactions Vol. 10 |
article | URL |
Abstract: Understory fires, which burn the floor of standing forests, are one of the most important types of forest impoverishment in the Amazon, especially during the severe droughts of El Nino - Southern Oscillation (ENSO) episodes. However, the authors are aware of no estimates of the areal extent of these fires for the Brazilian Amazon and, hence, of their contribution to Amazon carbon fluxes to the atmosphere. In this paper, the area of forest understory fires for the Brazilian Amazon region is calculated during an El Nino ( 1998) and a non - El Nino ( 1995) year based on forest fire scars mapped with satellite images for three locations in eastern and southern Amazonia, where deforestation is concentrated. The three study sites represented a gradient of both forest types and dry season severity. The burning scar maps were used to determine how the percentage of forest that burned varied with distance from agricultural clearings. These spatial functions were then applied to similar forest/climate combinations outside of the study sites to derive an initial estimate for the Brazilian Amazon. Ninety-one percent of the forest area that burned in the study sites was within the first kilometer of a clearing for the non-ENSO year and within the first four kilometers for the ENSO year. The area of forest burned by understory forest fire during the severe drought (ENSO) year (3.9 x 10(6) ha) was 13 times greater than the area burned during the average rainfall year (0.2 x 10(6) ha), and twice the area of annual deforestation. Dense forest was, proportionally, the forest type most affected by understory fires during the El Nino year, while understory fires were concentrated in transitional forests during the year of average rainfall. The estimate here of aboveground tree biomass killed by fire ranged from 0.049 to 0.329 Pg during the ENSO and from 0.003 to 0.021 Pg during the non-ENSO year. | |||||
BibTeX:
@article{alencar_forest_2006, author = {Alencar, A. and Nepstad, D. and Vera Diaz, M. del C.}, title = {Forest understory fire in the Brazilian Amazon in ENSO and non-ENSO years: Area burned and committed carbon emissions}, journal = {Earth Interactions}, year = {2006}, volume = {10}, url = {://WOS:000241360000001} } |
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Alencar, A., Asner, G.P., Knapp, D. and Zarin, D. | Temporal variability of forest fires in eastern Amazonia | 2011 | Ecological Applications Vol. 21(7), pp. 2397-2412 |
article | URL |
Abstract: Widespread occurrence of fires in Amazonian forests is known to be associated with extreme droughts, but historical data on the location and extent of forest fires are fundamental to determining the degree to which climate conditions and droughts have affected fire occurrence in the region. We used remote sensing to derive a 23-year time series of annual landscape-level burn scars in a fragmented forest of the eastern Amazon. Our burn scar data set is based on a new routine developed for the Carnegie Landsat Analysis System (CLAS), called CLAS-BURN, to calculate a physically based burn scar index (BSI) with an overall accuracy of 93% (Kappa coefficient 0.84). This index uses sub-pixel cover fractions of photosynthetic vegetation, non-photosynthetic vegetation, and shade/burn scar spectral end members. From 23 consecutive Landsat images processed with the CLAS-BURN algorithm, we quantified fire frequencies, the variation in fire return intervals, and rates of conversion of burned forest to other land uses in a 32 400 km 2 area. From 1983 to 2007, 15% of the forest burned; 38% of these burned forests were subsequently deforested, representing 19% of the area cleared during the period of observation. While 72% of the fire-affected forest burned only once during the 23-year study period, 20% burned twice, 6% burned three times, and 2% burned four or more times, with the maximum of seven times. These frequencies suggest that the current fire return interval is 5-11 times more frequent than the estimated natural fire regime. Our results also quantify the substantial influence of climate and extreme droughts caused by a strong El Nino Southern Oscillation (ENSO) on the extent and likelihood of returning forest fires mainly in fragmented landscapes. These results are an important indication of the role of future warmer climate and deforestation in enhancing emissions from more frequently burned forests in the Amazon. | |||||
BibTeX:
@article{alencar_temporal_2011, author = {Alencar, Ane and Asner, Gregory P. and Knapp, David and Zarin, Daniel}, title = {Temporal variability of forest fires in eastern Amazonia}, journal = {Ecological Applications}, year = {2011}, volume = {21}, number = {7}, pages = {2397--2412}, note = {Edition: 2011/11/12}, url = {://WOS:000296139200005} } |
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Aleixo, A., Peterson, A.T., Araújo-Silva, L.E., Bandeira, C.H.M.d.M., Batista, R., Burlamaqui, T.C.T., Dantas, S.d.M., Fernandes, A.M., Ferreira, M., Martins, D.M., Rêgo, P.S., Ribas, C.C., Rocha, T.C., Santos, M.P.S., Sardelli, C.H., Sequeira, F., Soares, L.M.d.S., Sousa, B.R.S.d., Sousa, S.d.A., Sousa-Neves, T. and Vallinoto, G.T.e.M. | Instabilidade climática e diversificação de espécies na Amazônia [BibTeX] |
2014 | Vol. 1(1)Cenários para a Amazônia: clima, biodiversidade e uso da terra, pp. 43-56 |
incollection | |
BibTeX:
@incollection{emilio_instabilidade_2014, author = {Aleixo, Alexandre and Peterson, A. Townsend and Araújo-Silva, Lucas Eduardo and Bandeira, Cinthia Helena Miléo de M. and Batista, Romina and Burlamaqui, Tibério Cesar Tortola and Dantas, Sidnei de Melo and Fernandes, Alexandre M. and Ferreira, Mateus and Martins, Denise Mendes and Rêgo, Péricles S. and Ribas, Camila C. and Rocha, Tainá C. and Santos, Marcos Pérsio Santas and Sardelli, Carla Haisler and Sequeira, Fernando and Soares, Leonardo Moura dos Santos and Sousa, Barbara Regina Silva de and Sousa, Shirliane de Araújo and Sousa-Neves, Tiago and Vallinoto, Gregory Thom e Marcelo}, title = {Instabilidade climática e diversificação de espécies na Amazônia}, booktitle = {Cenários para a Amazônia: clima, biodiversidade e uso da terra}, publisher = {Editora INPA}, year = {2014}, volume = {1}, number = {1}, pages = {43--56}, note = {Section: 4} } |
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Aldrich, S., Walker, R., Arima, E., Caldas, M., Browder, J. and Perz, S. | Land-cover and land-use change in the Brazilian Amazon: Smallholders, ranchers, and frontier stratification | 2006 | Economic Geography Vol. 82(3), pp. 265-288 |
article | URL |
Abstract: Tropical deforestation is a significant driver of global environmental change, given its impacts on the carbon cycle and biodiversity. Loss of the Amazon forest, the focus of this article, is of particular concern because of the size and the rapid rate at which the forest is being converted to agricultural use. In this article, we identify what has been the most important driver of deforestation in a specific colonization frontier in the Brazilian Amazon. To this end, we consider (1) the land-use dynamics of smallholder households, (2) the formation of pasture by large-scale ranchers, and (3) structural processes of land aggregation by ranchers. Much has been written about relation between smallholders and ranchers in the Brazilian Amazon, particularly those involving conflict over land, and this article explicates the implications of such social processes for land cover. Toward this end, we draw on panel data (1996-2002) and satellite imagery (1986-1999) to show the deforestation that is attributable to small- and largeholders, and the deforestation that is attributable to aggregations of property arising from a process that we refer to as frontier stratification. Evidently, most of the recent deforestation in the study area has resulted from the household processes of smallholders, not from conversions to pasture pursuant to the appropriations of smallholders' property by well-capitalized ranchers or speculators. | |||||
BibTeX:
@article{aldrich_land-cover_2006, author = {Aldrich, S.P. and Walker, R.T. and Arima, E.Y. and Caldas, M.M. and Browder, J.O. and Perz, S.}, title = {Land-cover and land-use change in the Brazilian Amazon: Smallholders, ranchers, and frontier stratification}, journal = {Economic Geography}, year = {2006}, volume = {82}, number = {3}, pages = {265--288}, url = {://WOS:000240013200002} } |
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Alcantara, E.d., Stech, J., Leao de Moraes Novo, E., Shimabukuro, Y. and Faria Barbosa, C. | Turbidity in the Amazon Floodplain Assessed Through a Spatial Regression Model Applied to Fraction Images Derived From MODIS/Terra | 2008 | Ieee Transactions on Geoscience and Remote Sensing Vol. 46(10), pp. 2895-2905 |
article | DOI URL |
Abstract: The objective of this paper was to estimate turbidity in the Curuai floodplain during the high water level period. Spatial regression models were developed by using fraction images derived from a linear spectral mixture model applied to a Moderate Resolution Imaging Spectroradiometer/Terra image and turbidity in situ data. As the turbidity in situ data showed spatial autocorrelation. they were divided into four spatial regimes (clusters). Thus, a spatial regression model was developed for each spatial regime. Through the Akaike information criterion, it was verified which spatial regime showed the best fit in the spatial regression model. The best fit was presented by the spatial regime 4 (R-2 = 0.80, p textless 0.05). Then. the spatial regression model developed for the spatial regime 4 was applied to all floodplain lakes. The spatial regression models show potential for assessing the water turbidity in aquatic systems by considering a spatial dependence between samples. | |||||
BibTeX:
@article{alcantara_turbidity_2008, author = {Alcantara, E.H. de and Stech, J.L. and Leao de Moraes Novo, E.M. and Shimabukuro, Y.E. and Faria Barbosa, C.C.}, title = {Turbidity in the Amazon Floodplain Assessed Through a Spatial Regression Model Applied to Fraction Images Derived From MODIS/Terra}, journal = {Ieee Transactions on Geoscience and Remote Sensing}, year = {2008}, volume = {46}, number = {10}, pages = {2895--2905}, url = {://WOS:000260000300015 http://ieeexplore.ieee.org/ielx5/36/4637826/04610925.pdf?tp=&arnumber=4610925&isnumber=4637826}, doi = {https://doi.org/10.1109/tgrs.2008.916648} } |
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Alcantara, E.H., Stech, J.L., Lorenzzetti, J.A., Bonnet, M.P., Casamitjana, X., Assireu, A.T. and Leao de Moraes Novo, E.M. | Remote sensing of water surface temperature and heat flux over a tropical hydroelectric reservoir | 2010 | Remote Sensing of Environment Vol. 114(11), pp. 2651-2665 |
article | DOI URL |
Abstract: Water temperature plays an important role in ecological functioning and in controlling the biogeochemical processes of a water body. Conventional water quality monitoring is expensive and time consuming. It is particularly problematic if the water bodies to be examined are large. Conventional techniques also bring about a high probability of undersampling. Conversely, remote sensing is a powerful tool to assess aquatic systems. The objective of this study was to map the surface water temperature and improve understanding of spatiotemporal variations in a hydroelectric reservoir. In this work, MODIS land-surface temperature (LST) level 2, 1-km nominal resolution data (MOD11L2, version 5) were used. All available clear-sky MODIS/Terra images from 2003 to 2008 were used, resulting in a total of 786 daytime and 473 nighttime images. Descriptive statistics (mean, maximum and minimum) were computed for the historical images to build a time series of daytime and nighttime monthly mean temperatures. The thermal amplitude and anomaly were also computed. In-situ meteorological variables were used from 2003 to 2008 to help understand the spatiotemporal variability of the surface water temperature. The surface energy budget and the depth at which the wind can distribute the heat input of a given surface were also measured. A correlation between daytime and nighttime surface water temperatures and the computed heat fluxes were made. These relationships and the causes of the water surface temperature variability are discussed. (C) 2010 Elsevier Inc. All rights reserved. | |||||
BibTeX:
@article{alcantara_remote_2010, author = {Alcantara, Enner Herenio and Stech, Jose Luiz and Lorenzzetti, Joao Antonio and Bonnet, Marie Paule and Casamitjana, Xavier and Assireu, Arcilan Trevenzoli and Leao de Moraes Novo, Evlyn Marcia}, title = {Remote sensing of water surface temperature and heat flux over a tropical hydroelectric reservoir}, journal = {Remote Sensing of Environment}, year = {2010}, volume = {114}, number = {11}, pages = {2651--2665}, url = {://WOS:000282242000022 http://ac.els-cdn.com/S0034425710001926/1-s2.0-S0034425710001926-main.pdf?_tid=9dfc823c-03f1-11e2-88f3-00000aab0f27&acdnat=1348234884_edb8b1ffb36fbe57a7874346eff3e5e8}, doi = {https://doi.org/10.1016/j.rse.2010.06.002} } |
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Alcantara, E., Novo, E., Stech, J., Lorenzzetti, J., Barbosa, C., Assireu, A. and Souza, A. | A contribution to understanding the turbidity behaviour in an Amazon floodplain | 2010 | Hydrology and Earth System Sciences Vol. 14(2), pp. 351-364 |
article | URL |
Abstract: Observations of turbidity provide quantitative information about water quality. However, the number of available in situ measurements for water quality determination is usually limited in time and space. Here, we present an analysis of the temporal and spatial variability of the turbidity of an Amazon floodplain lake using two approaches: (1) wavelet analysis of a turbidity time series measured by an automatic monitoring system, which should be improved/simplified, and (2) turbidity samples measured in different locations and then interpolated using an ordinary Kriging algorithm. The spatial and temporal variability of turbidity are clearly related to the Amazon River flood pulses in the floodplain. When the water level in the floodplain is rising or receding, the exchange between the Amazon River and the floodplain is the major driving force in turbidity variability. At high-water levels, turbidity variability is controlled by Lake Bathymetry. When the water level is low, wind action and Lake Morphometry are the main causes of turbidity variability. The combined use of temporal and spatial data shows a good potential for better understanding of the turbidity behaviour in a complex aquatic system such as the Amazon floodplain. | |||||
BibTeX:
@article{alcantara_contribution_2010, author = {Alcantara, E. and Novo, E. and Stech, J. and Lorenzzetti, J. and Barbosa, C. and Assireu, A. and Souza, A.}, title = {A contribution to understanding the turbidity behaviour in an Amazon floodplain}, journal = {Hydrology and Earth System Sciences}, year = {2010}, volume = {14}, number = {2}, pages = {351--364}, url = {://WOS:000274994800014} } |
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Alcantara, C.R., Silva Dias, M.A.F., Souza, E.P. and Cohen, J.C.P. | Verification of the role of the low level jets in Amazon squall lines | 2011 | Atmospheric Research Vol. 100(1), pp. 36-44 |
article | DOI URL |
Abstract: In this study we present a climatology of the Amazon squall lines (ASLs), between the years 2000 and 2008, using satellite imagery and European Centre for Medium-Range Weather Forecasts (ECMWF) reanalyses. The ASLs we are interested in are typically formed along the northern coast of Brazil and sometimes propagate for long distances inland. Results show that, on average, an ASL occurs every 2 days. ASLs are more frequent between April and June and less frequent between October and November. The years of 2005 and 2006 showed 25% more cases than the other years. This might be related to an increase of the Atlantic sea surface temperature. Of the total number of ASL cases, 54% propagated less than 170 km, 26% propagated between 170 and 400 km, and 20% propagated more than 400 km. We also studied the occurrence of low level jets (LLJs) associated with the coastal ASLs. Although LLJs are always present in the environment before the formation of the ASL and even on days without ASL cases, important differences were found, mainly related to the LLJ depths. (C) 2010 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{alcantara_verification_2011, author = {Alcantara, Clenia R. and Silva Dias, Maria A. F. and Souza, Enio P. and Cohen, Julia C. P.}, title = {Verification of the role of the low level jets in Amazon squall lines}, journal = {Atmospheric Research}, year = {2011}, volume = {100}, number = {1}, pages = {36--44}, url = {://WOS:000288770400004 http://ac.els-cdn.com/S0169809510003704/1-s2.0-S0169809510003704-main.pdf?_tid=96f0785e-03f1-11e2-a004-00000aacb362&acdnat=1348234872_2549640b7d0fac47995e956dcbeddf73}, doi = {https://doi.org/10.1016/j.atmosres.2010.12.023} } |
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Albrecht, R. and Silva-Dias, M. | Microphysical evidence of the transition between predominant convective/stratiform rainfall associated with the intraseasonal oscillation in the Southwest Amazon [BibTeX] |
2005 | Acta Amazonica Vol. 35, pp. 175-184 |
article | |
BibTeX:
@article{albrecht_microphysical_2005, author = {Albrecht, R.I. and Silva-Dias, M.A.F.}, title = {Microphysical evidence of the transition between predominant convective/stratiform rainfall associated with the intraseasonal oscillation in the Southwest Amazon}, journal = {Acta Amazonica}, year = {2005}, volume = {35}, pages = {175--184} } |
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Albrecht, R.I., Morales, C.A. and Dias, M.A.F.S. | Electrification of precipitating systems over the Amazon: Physical processes of thunderstorm development | 2011 | Journal of Geophysical Research-Atmospheres Vol. 116 |
article | DOI URL |
Abstract: This study investigated the physical processes involved in the development of thunderstorms over southwestern Amazon by hypothesizing causalities for the observed cloud-to-ground lightning variability and the local environmental characteristics. Southwestern Amazon experiences every year a large variety of environmental factors, such as the gradual increase in atmospheric moisture, extremely high pollution due to biomass burning, and intense deforestation, which directly affects cloud development by differential surface energy partition. In the end of the dry period it was observed higher percentages of positive cloud-to-ground (+CG) lightning due to a relative increase in +CG dominated thunderstorms (positive thunderstorms). Positive (negative) thunderstorms initiated preferentially over deforested (forest) areas with higher (lower) cloud base heights, shallower (deeper) warm cloud depths, and higher (lower) convective potential available energy. These features characterized the positive (negative) thunderstorms as deeper (relatively shallower) clouds, stronger (relatively weaker) updrafts with enhanced (decreased) mixed and cold vertically integrated liquid. No significant difference between thunderstorms (negative and positive) and nonthunderstorms were observed in terms of atmospheric pollution, once the atmosphere was overwhelmed by pollution leading to an updraft-limited regime. However, in the wet season both negative and positive thunderstorms occurred during periods of relatively higher aerosol concentration and differentiated size distributions, suggesting an aerosol-limited regime where cloud electrification could be dependent on the aerosol concentration to suppress the warm and enhance the ice phase. The suggested causalities are consistent with the invoked hypotheses, but they are not observed facts; they are just hypotheses based on plausible physical mechanisms. | |||||
BibTeX:
@article{albrecht_electrification_2011, author = {Albrecht, R. I. and Morales, C. A. and Dias, M. A. F. S.}, title = {Electrification of precipitating systems over the Amazon: Physical processes of thunderstorm development}, journal = {Journal of Geophysical Research-Atmospheres}, year = {2011}, volume = {116}, url = {://000289853400001 http://www.agu.org/journals/jd/jd1108/2010JD014756/2010JD014756.pdf}, doi = {https://doi.org/10.1029/2010jd014756} } |
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Albert, L.P., Wu, J., Prohaska, N., de Camargo, P.B., Huxman, T.E., Tribuzy, E.S., Ivanov, V.Y., Oliveira, R.S., Garcia, S., Smith, M.N., Oliveira Junior, R.C., Restrepo-Coupe, N., da Silva, R., Stark, S.C., Martins, G.A., Penha, D.V. and Saleska, S.R. | Age-dependent leaf physiology and consequences for crown-scale carbon uptake during the dry season in an Amazon evergreen forest | 2018 | New Phytologist Vol. 219(3), pp. 870-884 |
article | DOI URL |
Abstract: Summary Satellite and tower-based metrics of forest-scale photosynthesis generally increase with dry season progression across central Amazônia, but the underlying mechanisms lack consensus. We conducted demographic surveys of leaf age composition, and measured the age dependence of leaf physiology in broadleaf canopy trees of abundant species at a central eastern Amazon site. Using a novel leaf-to-branch scaling approach, we used these data to independently test the much-debated hypothesis – arising from satellite and tower-based observations – that leaf phenology could explain the forest-scale pattern of dry season photosynthesis. Stomatal conductance and biochemical parameters of photosynthesis were higher for recently mature leaves than for old leaves. Most branches had multiple leaf age categories simultaneously present, and the number of recently mature leaves increased as the dry season progressed because old leaves were exchanged for new leaves. These findings provide the first direct field evidence that branch-scale photosynthetic capacity increases during the dry season, with a magnitude consistent with increases in ecosystem-scale photosynthetic capacity derived from flux towers. Interactions between leaf age-dependent physiology and shifting leaf age-demographic composition are sufficient to explain the dry season photosynthetic capacity pattern at this site, and should be considered in vegetation models of tropical evergreen forests. | |||||
BibTeX:
@article{albert_age-dependent_2018, author = {Albert, Loren P. and Wu, Jin and Prohaska, Neill and de Camargo, Plinio Barbosa and Huxman, Travis E. and Tribuzy, Edgard S. and Ivanov, Valeriy Y. and Oliveira, Rafael S. and Garcia, Sabrina and Smith, Marielle N. and Oliveira Junior, Raimundo Cosme and Restrepo-Coupe, Natalia and da Silva, Rodrigo and Stark, Scott C. and Martins, Giordane A. and Penha, Deliane V. and Saleska, Scott R.}, title = {Age-dependent leaf physiology and consequences for crown-scale carbon uptake during the dry season in an Amazon evergreen forest}, journal = {New Phytologist}, year = {2018}, volume = {219}, number = {3}, pages = {870--884}, url = {https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.15056}, doi = {https://doi.org/10.1111/nph.15056} } |
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Ahlm, L., Nilsson, E.D., Krejci, R., Martensson, E.M., Vogt, M. and Artaxo, P. | A comparison of dry and wet season aerosol number fluxes over the Amazon rain forest | 2010 | Atmospheric Chemistry and Physics Vol. 10(6), pp. 3063-3079 |
article | URL |
Abstract: Vertical number fluxes of aerosol particles and vertical fluxes of CO(2) were measured with the eddy covariance method at the top of a 53 m high tower in the Amazon rain forest as part of the LBA (The Large Scale Biosphere Atmosphere Experiment in Amazonia) experiment. The observed aerosol number fluxes included particles with sizes down to 10 nm in diameter. The measurements were carried out during the wet and dry season in 2008. In this study focus is on the dry season aerosol fluxes, with significant influence from biomass burning, and these are compared with aerosol fluxes measured during the wet season. Net particle deposition fluxes dominated in daytime in both seasons and the deposition flux was considerably larger in the dry season due to the much higher dry season particle concentration. The particle transfer velocity increased linearly with increasing friction velocity in both seasons. The difference in transfer velocity between the two seasons was small, indicating that the seasonal change in aerosol number size distribution is not enough for causing any significant change in deposition velocity. In general, particle transfer velocities in this study are low compared to studies over boreal forests. The reasons are probably the high percentage of accumulation mode particles and the low percentage of nucleation mode particles in the Amazon boundary layer, both in the dry and wet season, and low wind speeds in the tropics compared to the midlatitudes. In the dry season, nocturnal particle fluxes behaved very similar to the nocturnal CO(2) fluxes. Throughout the night, the measured particle flux at the top of the tower was close to zero, but early in the morning there was an upward particle flux peak that is not likely a result of entrainment or local pollution. It is possible that these morning upward particle fluxes are associated with emission of primary biogenic particles from the rain forest. Emitted particles may be stored within the canopy during stable conditions at nighttime, similarly to CO(2), and being released from the canopy when conditions become more turbulent in the morning. | |||||
BibTeX:
@article{ahlm_comparison_2010, author = {Ahlm, L. and Nilsson, E. D. and Krejci, R. and Martensson, E. M. and Vogt, M. and Artaxo, P.}, title = {A comparison of dry and wet season aerosol number fluxes over the Amazon rain forest}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {6}, pages = {3063--3079}, url = {://WOS:000276182100032} } |
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Ahlm, L., Nilsson, E.D., Krejci, R., Martensson, E.M., Vogt, M. and Artaxo, P. | Aerosol number fluxes over the Amazon rain forest during the wet season | 2009 | Atmospheric Chemistry and Physics Vol. 9(24), pp. 9381-9400 |
article | URL |
Abstract: Number fluxes of particles with diameter larger than 10 nm were measured with the eddy covariance method over the Amazon rain forest during the wet season as part of the LBA (The Large Scale Biosphere Atmosphere Experiment in Amazonia) campaign 2008. The primary goal was to investigate whether sources or sinks dominate the aerosol number flux in the tropical rain forest-atmosphere system. During the measurement campaign, from 12 March to 18 May, 60% of the particle fluxes pointed downward, which is a similar fraction to what has been observed over boreal forests. The net deposition flux prevailed even in the absolute cleanest atmospheric conditions during the campaign and therefore cannot be explained only by deposition of anthropogenic particles. The particle transfer velocity v(t) increased with increasing friction velocity and the relation is described by the equation v(t) = 2.4x10(-3)xu(*) where u(*) is the friction velocity. Upward particle fluxes often appeared in the morning hours and seem to a large extent to be an effect of entrainment fluxes into a growing mixed layer rather than primary aerosol emission. In general, the number source of primary aerosol particles within the footprint area of the measurements was small, possibly because the measured particle number fluxes reflect mostly particles less than approximately 200 nm. This is an indication that the contribution of primary biogenic aerosol particles to the aerosol population in the Amazon boundary layer may be low in terms of number concentrations. However, the possibility of horizontal variations in primary aerosol emission over the Amazon rain forest cannot be ruled out. | |||||
BibTeX:
@article{ahlm_aerosol_2009, author = {Ahlm, L. and Nilsson, E. D. and Krejci, R. and Martensson, E. M. and Vogt, M. and Artaxo, P.}, title = {Aerosol number fluxes over the Amazon rain forest during the wet season}, journal = {Atmospheric Chemistry and Physics}, year = {2009}, volume = {9}, number = {24}, pages = {9381--9400}, url = {://WOS:000273060200004} } |
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Ahlm, L., Krejci, R., Nilsson, E.D., Martensson, E.M., Vogt, M. and Artaxo, P. | Emission and dry deposition of accumulation mode particles in the Amazon Basin | 2010 | Atmospheric Chemistry and Physics Vol. 10(21), pp. 10237-10253 |
article | DOI URL |
Abstract: Size-resolved vertical aerosol number fluxes of particles in the diameter range 0.25-2.5 mu m were measured with the eddy covariance method from a 53 m high tower over the Amazon rain forest, 60 km NNW of Manaus, Brazil. This study focuses on data measured during the relatively clean wet season, but a shorter measurement period from the more polluted dry season is used as a comparison. Size-resolved net particle fluxes of the five lowest size bins, representing 0.25-0.45 mu m in diameter, were in general dominated by deposition in more or less all wind sectors in the wet season. This is an indication that the source of primary biogenic aerosol particles may be small in this particle size range. Transfer velocities within this particle size range were observed to increase linearly with increasing friction velocity and increasing particle diameter. In the diameter range 0.5-2.5 mu m, vertical particle fluxes were highly dependent on wind direction. In wind sectors where anthropogenic influence was low, net upward fluxes were observed. However, in wind sectors associated with higher anthropogenic influence, deposition fluxes dominated. The net upward fluxes were interpreted as a result of primary biogenic aerosol emission, but deposition of anthropogenic particles seems to have masked this emission in wind sectors with higher anthropogenic influence. The net emission fluxes were at maximum in the afternoon when the mixed layer is well developed, and were best correlated with horizontal wind speed according to the equation log(10)F = 0.48.U + 2.21 where F is the net emission number flux of 0.5-2.5 mu m particles [m(-2) s(-1)] and U is the horizontal wind speed [ms(-1)] at the top of the tower. | |||||
BibTeX:
@article{ahlm_emission_2010, author = {Ahlm, L. and Krejci, R. and Nilsson, E. D. and Martensson, E. M. and Vogt, M. and Artaxo, P.}, title = {Emission and dry deposition of accumulation mode particles in the Amazon Basin}, journal = {Atmospheric Chemistry and Physics}, year = {2010}, volume = {10}, number = {21}, pages = {10237--10253}, url = {://WOS:000284210400006 http://www.atmos-chem-phys.net/10/10237/2010/acp-10-10237-2010.pdf}, doi = {https://doi.org/10.5194/acp-10-10237-2010} } |
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Aguila-Pasquel, J.d., Doughty, C.E., Metcalfe, D.B., Silva-Espejo, J.E., Girardin, C.A., Gutierrez, J.A.C., Navarro-Aguilar, G.E., Quesada, C.A., Hidalgo, C.G., Huaymacari, J.M.R., Halladay, K., Dennis del Castillo Torres, Phillips, O. and Malhi, Y. | The seasonal cycle of productivity, metabolism and carbon dynamics in a wet aseasonal forest in north-west Amazonia (Iquitos, Peru) [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 71-83 |
article | |
BibTeX:
@article{aguila-pasquel_seasonal_2014, author = {Aguila-Pasquel, Jhon del and Doughty, Christopher E. and Metcalfe, Daniel B. and Silva-Espejo, Javier E. and Girardin, Cecile A.J. and Gutierrez, Jack A. Chung and Navarro-Aguilar, Gilberto E. and Quesada, Carlos A. and Hidalgo, Carlos G. and Huaymacari, Jose M. Reyna and Halladay, Kate and Dennis del Castillo Torres and Phillips, Oliver and Malhi, Yadvinder}, title = {The seasonal cycle of productivity, metabolism and carbon dynamics in a wet aseasonal forest in north-west Amazonia (Iquitos, Peru)}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {71--83} } |
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Aguiar, R.G., Musis, C.R.D., Aguiar, L.J.G., Martínez-Espinosa, M. and Fischer, G.R. | Energy balance closure in the Southwest Amazon forest site—a statistical approach [BibTeX] |
2019 | Theoretical and Applied Climatology Vol. 136(3–4), pp. 1209-1219 |
article | |
BibTeX:
@article{aguiar_energy_2019, author = {Aguiar, Renata Gonçalves and Musis, Carlo Ralph De and Aguiar, Leonardo José Gonçalves and Martínez-Espinosa, Mariano and Fischer, Graciela Redies}, title = {Energy balance closure in the Southwest Amazon forest site—a statistical approach}, journal = {Theoretical and Applied Climatology}, year = {2019}, volume = {136}, number = {3–4}, pages = {1209--1219} } |
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Aguiar, R., Priante-Filho, C., Manzi, N., Aguiar, A.O., L.J.G., C. and F.L ., R. | Fluxos de massa e energia em uma floresta tropical no sudoeste da Amazônia [BibTeX] |
2006 | Revista Brasileira de Meteorologia Vol. 21(3b), pp. 248-257 |
article | |
BibTeX:
@article{aguiar_fluxos_2006, author = {Aguiar, Randow, C., Priante-Filho, N., Manzi, A.O., Aguiar, L.J.G., Cardoso, F.L ., R.G.}, title = {Fluxos de massa e energia em uma floresta tropical no sudoeste da Amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2006}, volume = {21}, number = {3b}, pages = {248--257} } |
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Aguiar, L.J.G., Fischer, G.R., Ladle, R.J., Malhado, A.C.M., Justino, F.B., Aguiar, R.G. and Costa, J.M.N. | Modeling the photosynthetically active radiation in South West Amazonia under all sky conditions. [BibTeX] |
2011 | Theoretical and Applied Climatology, pp. DOI 10.1007/s00704-011-0556-z | article | |
BibTeX:
@article{aguiar_modeling_2011, author = {Aguiar, L. J. G. and Fischer, G. R. and Ladle, R. J. and Malhado, A. C. M. and Justino, F. B. and Aguiar, R. G. and Costa, J. M. N.}, title = {Modeling the photosynthetically active radiation in South West Amazonia under all sky conditions.}, journal = {Theoretical and Applied Climatology}, year = {2011}, pages = {DOI 10.1007/s00704--011--0556--z} } |
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Aguiar, L.J.G., da Costa, J.M.N., Aguiar, R.G. and Fischer, G.R. | Estimates and Measurements of Photosynthetically Active Radiation and Global Solar Irradiance in Rondonia | 2009 | Vol. 1100Current Problems in Atmospheric Radiation, pp. 435-438 |
incollection | URL |
Abstract: Measurements of photosynthetically active radiation (PAR) and global solar irradiance (R(s)) were made at a LBA (The Large Scale Biosphere-Atmosphere Experiment in Amazonia) experimental site, at Fazenda Nossa Senhora. (10 degrees 45' S 62 degrees 21' W), in Rondonia, in the years of 2004 and 2005. with the objective of estimating the seasonal variation of the ratio between the photosynthetically active radiation and the global solar irradiance. The relationship between PAR and R, were made by using linear regressions equations with data from year 2004 and tested with data from the year 2005. The seasonal variation of the ratio PAR/R(s) ranged from 0.43 (September) to 0.48 (January). The linear regression equations between PAR and R, obtained were: a) On an hourly basis: PAR=0.747+0.478*R(s), (R(2)= 0.99; wet season) and PAR=-4.578+0.452*R(s) (R(2)= 0.99; dry season); b) On a daily basis: PAR=4.956+0.466*R(s) (R(2)= 0.99: wet season) and PAR=-6.762+0.457*R(s) (R(2)= 0.96; dry season). | |||||
BibTeX:
@incollection{nakajima_estimates_2009, author = {Aguiar, Leonardo J. G. and da Costa, Jose M. N. and Aguiar, Renata G. and Fischer, Graciela R.}, title = {Estimates and Measurements of Photosynthetically Active Radiation and Global Solar Irradiance in Rondonia}, booktitle = {Current Problems in Atmospheric Radiation}, year = {2009}, volume = {1100}, pages = {435--438}, url = {://WOS:000265672300106} } |
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Aguiar, L.J.G., Costa, J.M.N.d., Fischer, G.R., Aguiar, R.G., da Costa, A.C.L. and Ferreira, W.P.M. | Estimativa da radiação de onda longa atmosférica em áreas de floresta e pastagem no sudoeste da amazônia [BibTeX] |
2011 | Revista Brasileira de Meteorologia Vol. 26, pp. 215 - 224 |
article | |
BibTeX:
@article{aguiar_estimativa_2011, author = {Aguiar, L. J. G. and Costa, José Maria Nogueira da and Fischer, G. R. and Aguiar, R. G. and da Costa, A. C. L. and Ferreira, W. P. M.}, title = {Estimativa da radiação de onda longa atmosférica em áreas de floresta e pastagem no sudoeste da amazônia}, journal = {Revista Brasileira de Meteorologia}, year = {2011}, volume = {26}, pages = {215 -- 224} } |
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Aguiar Jr., A., Barbosa, R.I., Barbosa, J.B. and Mourão Jr., M. | Invasion of Acacia mangium in Amazonian savannas following planting for forestry [BibTeX] |
2014 | PLANT ECOLOGY & DIVERSITY Vol. 7(1-2), pp. 359-370 |
article | |
BibTeX:
@article{aguiar_jr_invasion_2014, author = {Aguiar Jr., Agnaldo and Barbosa, Reinaldo I. and Barbosa, José B.F. and Mourão Jr., Moisés}, title = {Invasion of Acacia mangium in Amazonian savannas following planting for forestry}, journal = {PLANT ECOLOGY & DIVERSITY}, year = {2014}, volume = {7}, number = {1-2}, pages = {359--370} } |
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Aguiar, D.R., Oliveira Junior, R.C., Tapajós, R.P., Bareto, W.M., Silva, R.d. and Beldine, T.P. | Mecanismos de controle para fluxo de vapor d’água na FLONA Tapajós para o ano de 2002 [BibTeX] |
2013 | Revista Ciência e Natura Vol. Edição Esp. Dez. 2013(VIII Brazilian Micrometeorology Workshop), pp. 142 - 147 |
article | |
BibTeX:
@article{aguiar_mecanismos_2013, author = {Aguiar, Diego R. and Oliveira Junior, Raimundo C. and Tapajós, Raphael P. and Bareto, Wilderclay M. and Silva, Rodrigo da and Beldine, Troy P.}, title = {Mecanismos de controle para fluxo de vapor d’água na FLONA Tapajós para o ano de 2002}, journal = {Revista Ciência e Natura}, year = {2013}, volume = {Edição Esp. Dez. 2013}, number = {VIII Brazilian Micrometeorology Workshop}, pages = {142 -- 147} } |
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Aguiar, A.P.D., Ometto, J.P., Nobre, C., Lapola, D.M., Almeida, C., Vieira, I.C., Soares, J.V., Alvala, R., Saatchi, S., Valeriano, D. and Castilla-Rubio, J.C. | Modeling the spatial and temporal heterogeneity of deforestation-driven carbon emissions: the INPE-EM framework applied to the Brazilian Amazon [BibTeX] |
2012 | Global Change Biology Vol. 18(11), pp. 3346-3366 |
article | |
BibTeX:
@article{aguiar_modeling_2012, author = {Aguiar, Ana Paula Dutra and Ometto, Jean Pierre and Nobre, Carlos and Lapola, David Montenegro and Almeida, Claudio and Vieira, Ima Célia and Soares, João Vianei and Alvala, Regina and Saatchi, Sassan and Valeriano, Dalton and Castilla-Rubio, Juan Carlos}, title = {Modeling the spatial and temporal heterogeneity of deforestation-driven carbon emissions: the INPE-EM framework applied to the Brazilian Amazon}, journal = {Global Change Biology}, year = {2012}, volume = {18}, number = {11}, pages = {3346--3366} } |
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Adams, D.K., Fernandes, R.M.S. and Maia, J.M.F. | GNSS Precipitable Water Vapor from an Amazonian Rain Forest Flux Tower | 2011 | Journal of Atmospheric and Oceanic Technology Vol. 28(10), pp. 1192-1198 |
article | DOI URL |
Abstract: Understanding the complex interactions between water vapor fields and deep convection on the mesoscale requires observational networks with high spatial (kilometers) and temporal (minutes) resolution. In the equatorial tropics, where deep convection dominates the vertical distribution of the most important greenhouse substance water these mesoscale networks are nonexistent. Global Navigational Satellite System (GNSS) meteorological networks offer high temporal/spatial resolution precipitable water vapor, but infrastructure exigencies are great. The authors report here on very accurate precipitable water vapor (PWV) values calculated from a GNSS receiver installed on a highly nonideal Amazon rain forest flux tower. Further experiments with a mechanically oscillating platform demonstrate that errors and biases of approximately 1 mm (2%-3% of PWV) can be expected when compared with a stable reference GNSS receiver for two different geodetic grade receivers/antennas and processing methods [GPS-Inferred Positioning System (GIPSY) and GAMIT]. The implication is that stable fixed antennas are unnecessary for accurate calculation of precipitable water vapor regardless of processing techniques or geodetic grade receiver. | |||||
BibTeX:
@article{adams_gnss_2011, author = {Adams, David K. and Fernandes, Rui M. S. and Maia, Jair M. F.}, title = {GNSS Precipitable Water Vapor from an Amazonian Rain Forest Flux Tower}, journal = {Journal of Atmospheric and Oceanic Technology}, year = {2011}, volume = {28}, number = {10}, pages = {1192--1198}, url = {://WOS:000296658000002 http://journals.ametsoc.org/doi/abs/10.1175/JTECH-D-11-00082.1}, doi = {https://doi.org/10.1175/jtech-d-11-00082.1} } |
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Adams, D.K., Fernandes, R.M.S., Kursinski, E.R., Maia, J.M., Sapucci, L.F., Machado, L.A.T., Vitorello, I., Galera Monico, J.F., Holub, K.L., Gutman, S.I., Filizola, N. and Bennett, R.A. | A dense GNSS meteorological network for observing deep convection in the Amazon | 2011 | Atmospheric Science Letters Vol. 12(2), pp. 207-212 |
article | DOI URL |
Abstract: A dense Global Navigation Satellite System (GNSS) meteorological network (similar to 20 stations) in the central Amazon Basin in Brazil is being developed for long-term studies of deep convection/water vapor interactions and feedback. In this article, the network is described and preliminary results are presented: GNSS-derived precipitable water vapor is useful for tracking water vapor advection and in identifying convective events and water vapor convergence timescales. Upon network completion (early 2011), 3D water vapor field analyses and participation in the intensive field campaign GPM-CHUVA will provide unique data sets for initializing, constraining or validating high-resolution models or refining convective parameterizations. Copyright (C) 2011 Royal Meteorological Society | |||||
BibTeX:
@article{adams_dense_2011, author = {Adams, David K. and Fernandes, Rui M. S. and Kursinski, E. Robert and Maia, Jair M. and Sapucci, Luiz F. and Machado, Luiz A. T. and Vitorello, Icaro and Galera Monico, Joao Francisco and Holub, Kirk L. and Gutman, Seth I. and Filizola, Naziano and Bennett, Richard A.}, title = {A dense GNSS meteorological network for observing deep convection in the Amazon}, journal = {Atmospheric Science Letters}, year = {2011}, volume = {12}, number = {2}, pages = {207--212}, url = {://WOS:000289649200009 http://onlinelibrary.wiley.com/store/10.1002/asl.312/asset/312_ftp.pdf?v=1&t=h6hx2rry&s=2a52f3ac8c67f102b74ba0354f22ba12e3671e61}, doi = {https://doi.org/10.1002/asl.312} } |
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Adams, D.K., Fernandes, R.M.S., Holub, K.L., Gutman, S.I., Barbosa, H.M.J., Machado, L.A.T., Calheiros, A.J.P., Bennett, R.A., Kursinski, E.R., Sapucci, L.F., DeMets, C., Chagas, G.F.B., Arellano, A., Filizola, N., Amorim Rocha, A.A., Silva, R.A., Assunção, L.M.F., Cirino, G.G., Pauliquevis, T., Portela, B.T.T., Sá, A., de Sousa, J.M. and Tanaka, L.M.S. | The Amazon Dense GNSS Meteorological Network: A New Approach for Examining Water Vapor and Deep Convection Interactions in the Tropics [BibTeX] |
2015 | Bulletin of the American Meteorological Society Vol. 96(12), pp. 2151-2165 |
article | DOI URL |
BibTeX:
@article{adams_amazon_2015, author = {Adams, David K. and Fernandes, Rui M. S. and Holub, Kirk L. and Gutman, Seth I. and Barbosa, Henrique M. J. and Machado, Luiz A. T. and Calheiros, Alan J. P. and Bennett, Richard A. and Kursinski, E. Robert and Sapucci, Luiz F. and DeMets, Charles and Chagas, Glayson F. B. and Arellano, Ave and Filizola, Naziano and Amorim Rocha, Alciélio A. and Silva, Rosimeire Araújo and Assunção, Lilia M. F. and Cirino, Glauber G. and Pauliquevis, Theotonio and Portela, Bruno T. T. and Sá, André and de Sousa, Jeanne M. and Tanaka, Ludmila M. S.}, title = {The Amazon Dense GNSS Meteorological Network: A New Approach for Examining Water Vapor and Deep Convection Interactions in the Tropics}, journal = {Bulletin of the American Meteorological Society}, year = {2015}, volume = {96}, number = {12}, pages = {2151--2165}, url = {https://journals.ametsoc.org/view/journals/bams/96/12/bams-d-13-00171.1.xml}, doi = {https://doi.org/10.1175/bams-d-13-00171.1} } |
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Adams, D.K., Barbosa, H.M.J. and De Los Rios, K. | A spatiotemporal water vapor/deep convection correlation metric derived from the Amazon Dense GNSS Meteorological Network [BibTeX] |
2016 | Monthly Weather Review | article | DOI |
BibTeX:
@article{adams_spatiotemporal_2016, author = {Adams, D. K. and Barbosa, H. M. J. and De Los Rios, K.}, title = {A spatiotemporal water vapor/deep convection correlation metric derived from the Amazon Dense GNSS Meteorological Network}, journal = {Monthly Weather Review}, year = {2016}, doi = {https://doi.org/10.1175/MWR-D-16-0140.1} } |
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Ackerman, I.L., Teixeira, W., Riha, S.J., Lehmann, J. and Fernandes, E.C.M. | The impact of mound-building termites on surface soil properties in a secondary forest of Central Amazonia | 2007 | Applied Soil Ecology Vol. 37(3), pp. 267-276 |
article | DOI URL |
Abstract: Termites are important components of biologically mediated feedback to land-use change in the tropics. In Central Amazonia, termite mounds are prevalent in post-clearing landscapes and appear to constrain re-colonization of the landscape by vegetation. To determine the most important constraints imposed by termite mounds on plant establishment, we investigated chemical, physical, and hydraulic properties of termite mounds at an 8-yearold secondary forest site, and their effects on the development of native plant species. Mounds contained only half of the root biomass found in neighboring soil in the surface 0.05 m. Carbon, nitrogen, and potassium levels in the termite mounds were significantly elevated, by 33, 28, and 38%, respectively (44 g kg(-1), 2.5 g kg(-1), and 33 mg kg(-1)), while no significant difference in phosphorus, magnesium, iron, zinc, or copper concentrations was observed. Calcium was depleted by 27% in the termite mounds at 0.026 g kg(-1). Aluminum concentrations and acidity were significantly higher in the termite mound material (0.23 g kg(-1), pH 4.3) than surrounding soils (0.15 g kg(-1), pH 4.4). Resistance to penetration was significantly higher in termite mounds, at 13.5 MPa. Termite mounds were on average 5 mm drier than the control soil in the surface 0.05 m, with a significantly higher median water infiltration rate through the termite mound than the adjacent soil (16 mm s(-1) vs. 3 mm s(-1)). Although drainage through the mounds in situ was faster, termite mound samples absorbed water significantly more slowly than control soil. Termite mound material retained significantly less water than control soil under the same suction. Plant assays ruled out an effect of aluminum toxicity on seed germination and seedling development in termite mounds over control soil. Water availability and mechanical impedance were the most important constraints for seed germination and seedling development. The abundance of termite mounds was 760 ha(-1) in the study site, but covered only 3% of the area. Complementing the results from this study with investigations of termite mounds and nutrient cycling, carbon storage, and biodiversity will further our understanding of the effects of mound-building termites in the pastures and secondary forests of Amazonia. (c) 2007 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{ackerman_impact_2007, author = {Ackerman, I. L. and Teixeira, W.G. and Riha, Susan J. and Lehmann, J. and Fernandes, E. C. M.}, title = {The impact of mound-building termites on surface soil properties in a secondary forest of Central Amazonia}, journal = {Applied Soil Ecology}, year = {2007}, volume = {37}, number = {3}, pages = {267--276}, url = {://WOS:000250668000011 http://ac.els-cdn.com/S092913930700090X/1-s2.0-S092913930700090X-main.pdf?_tid=907a6296-03f1-11e2-8a04-00000aacb360&acdnat=1348234862_951e8f9f80afd7af945fa4784fc97878}, doi = {https://doi.org/10.1016/j.apsoil.2007.08.005} } |
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Ackerman, I.L., Constantino, R., Gauch Jr., H.G., Lehmann, J., Riha, S.J. and Fernandes, E.C.M. | Termite (Insecta: Isoptera) Species Composition in a Primary Rain Forest and Agroforests in Central Amazonia | 2009 | Biotropica Vol. 41(2), pp. 226-233 |
article | DOI URL |
Abstract: Termites play important roles in organic matter decomposition, nutrient cycling, and soil structure in tropical rain forests. When forests are replaced by agriculture, termite species richness, abundance, and function often decline. We compared the termite assemblage of a primary forest site with that of a low plant diversity, palm-based agroforest (five plant species) and a high plant diversity, home-garden agroforest (10 plant species) using a rapid biodiversity assessment protocol. In comparing the primary forest termite species composition to previously published studies, we found soil feeders and the Apicotermitinae to be more dominant than previously reported in Amazonia. Thirty percent of the species belonged to the Apicotermitinae, and an unusually high percentage (57%) of species were soil feeders. Unexpectedly, the palm-based agroforest, despite its lower plant diversity, was closer to primary forest in termite species composition, rate of species accumulation, and proportions of species in taxonomic and functional classes than was the home-garden agroforest. This suggests that particular plant attributes may better determine the termite assemblage than plant diversity alone in these agroecosystems. Unlike other agroecosystems reported in the literature, Apicotermitinae and soil feeders were proportionally more abundant in these agroforests than in primary forest. The ability of agroforests to support populations of soil feeders has a potentially positive effect on soil fertility in these agroecosystems; insomuch as feeding guild is a proxy for function, these closed-canopy agroforests may be able to sustain the same termite-mediated functions as primary forest. | |||||
BibTeX:
@article{ackerman_termite_2009, author = {Ackerman, Ilse L. and Constantino, Reginaldo and Gauch, Jr., Hugh G. and Lehmann, Johannes and Riha, Susan J. and Fernandes, Erick C. M.}, title = {Termite (Insecta: Isoptera) Species Composition in a Primary Rain Forest and Agroforests in Central Amazonia}, journal = {Biotropica}, year = {2009}, volume = {41}, number = {2}, pages = {226--233}, url = {://WOS:000263747000013 http://onlinelibrary.wiley.com/store/10.1111/j.1744-7429.2008.00479.x/asset/j.1744-7429.2008.00479.x.pdf?v=1&t=h6hx2d0a&s=6f01a21e1b28f4fd7122ec32d683013718372cbd}, doi = {https://doi.org/10.1111/j.1744-7429.2008.00479.x} } |
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Acevedo, O.C., Moraes, O.L.L., Fitzjarrald, D.R., Sakai, R.K. and Mahrt, L. | Turbulent carbon exchange in very stable conditions | 2007 | Boundary-Layer Meteorology Vol. 125(1), pp. 49-61 |
article | DOI URL |
Abstract: Turbulent fluxes obtained using the conventional eddy covariance approach result in erratic results with large time fluctuations in extremely stable conditions. This can limit efforts to estimate components of the nocturnal energy budget and respiratory CO2 fluxes. Well-organized fluxes that show a clear dependence on turbulent intensity were obtained when multiresolution decomposition was used to estimate turbulent exchanges. CO2, heat and water vapour fluxes were observed at a site in the eastern Amazon basin that had been cleared for agricultural purposes. Temporal scales of the carbon transfer were determined and shown to be similar to those of latent heat, but as much as three times larger than those of sensible heat. CO2 eddy diffusivities at the temporal scales on which most of the vertical CO2 exchange occurs are shown to be 50 times larger than the eddy diffusivity for heat. A process associated with the vertical scale of the scalar accumulation layer is suggested to explain these different scales and turbulent diffusivities of carbon and sensible heat transfer. For an appreciable range of turbulence intensities, the observed vertical turbulent carbon exchange is insufficient to account for the locally respired CO2 estimated independently. Evidence that shallow drainage currents may account for this is given. | |||||
BibTeX:
@article{acevedo_turbulent_2007, author = {Acevedo, Otavio C. and Moraes, Osvaldo L. L. and Fitzjarrald, David R. and Sakai, Ricardo K. and Mahrt, Larry}, title = {Turbulent carbon exchange in very stable conditions}, journal = {Boundary-Layer Meteorology}, year = {2007}, volume = {125}, number = {1}, pages = {49--61}, url = {://WOS:000249204600004 http://www.springerlink.com/content/961w134r345r0281/fulltext.pdf}, doi = {https://doi.org/10.1007/s10546-007-9193-6} } |
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Acevedo, O.C., Moraes, O.L.L., Degrazia, G.A., Fitzjarrald, D.R., Manzi, A.O. and Campos, J.G. | Is friction velocity the most appropriate scale for correcting nocturnal carbon dioxide fluxes? | 2009 | Agricultural and Forest Meteorology Vol. 149(1), pp. 1-10 |
article | DOI URL |
Abstract: The use of friction velocity u. as the turbulence scale for correcting eddy-covariance carbon dioxide fluxes in low-mixing conditions is questioned. This is done because U. is, itself, a flux and, therefore, its value is highly dependent on the temporal scale used for the analysis. The multiresolution decomposition is applied to data from three different ecosystems in Brazil, to show that u. is well behaved and related to the turbulent mixing only up to the scale that separates the turbulent mixing from the low-frequency exchange. For larger temporal scales, mesoscale fluxes may induce large variability in the friction velocity, so that time series with low turbulent mixing may show an elevated value for u., and vice-versa. We propose, as an alternative, the use of sigma(omega), the standard-deviation of the vertical velocity fluctuations. It is shown that sigma(omega) has no variability within the mesoscale range and that, therefore, it is a much better scale to quantify the turbulent exchange than u. The relationship between the two velocity scales is shown to depend on the scale and to be universal for the scales of the turbulent exchange. It is shown that curves of the turbulent carbon dioxide fluxes as a function of the turbulence scale are smoothed when using the friction velocity. Using sigma(omega) instead of u. in data filtering procedures has two main consequences: easier determination of the threshold for filtering and larger respiration rates of the series classified as turbulent. The improvement is larger for sites where very stable conditions are common. (c) 2008 Elsevier B.V. All rights reserved. | |||||
BibTeX:
@article{acevedo_is_2009, author = {Acevedo, Otavio C. and Moraes, Osvaldo L. L. and Degrazia, Gervasio A. and Fitzjarrald, David R. and Manzi, Antonio O. and Campos, Jose G.}, title = {Is friction velocity the most appropriate scale for correcting nocturnal carbon dioxide fluxes?}, journal = {Agricultural and Forest Meteorology}, year = {2009}, volume = {149}, number = {1}, pages = {1--10}, url = {://WOS:000262053400001 http://ac.els-cdn.com/S0168192308001962/1-s2.0-S0168192308001962-main.pdf?_tid=8a189468-03f1-11e2-a4be-00000aacb35e&acdnat=1348234851_7cdf54e559c637ca00253ece907ac8cc}, doi = {https://doi.org/10.1016/j.agrformet.2008.06.014} } |
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Acevedo, O.C., Moraes, O.L.L., Da Silva, R., Fitzjarrald, D.R., Sakai, R.K., Staebler, R.M. and Czikowsky, M.J. | Inferring nocturnal surface fluxes from vertical profiles of scalars in an Amazon pasture | 2004 | Global Change Biology Vol. 10(5), pp. 886-894 |
article | DOI URL |
Abstract: Ecosystem carbon budgets depend on there being good representative surface flux observations for all land use types during the entire diurnal cycle. In calm conditions that often occur at night, especially in areas of small roughness (such as pastures), ecosystem respiration rate is poorly measured using the eddy covariance (EC) technique. Nocturnal vertical profiles of temperature, humidity and winds were observed using tethered balloon soundings in a pasture in the eastern Amazon during two campaigns in 2001. The site is characterized by very weak winds at night, so that there is insufficient turbulence for the EC technique to determine fluxes accurately. To compensate, the time evolution of the profiles is used to determine surface fluxes at early morning and these are compared with those observed by EC at a nearby micrometeorological tower. The nocturnal boundary layer thickness h is determined as the height to which the surface fluxes must converge so that energy budget closure is achieved. The estimated values range from 30 m, around 22:00 hours LST, to more than 100 m just before dawn. These are in good agreement with the observed thickness of a frequently observed fog layer during the middle of the night. During the early portion of the night, when the accumulation layer is shallow, there is appreciable decrease of dCO(2)/dt with height. On calm nights, CO2 accumulation rate is larger near the surface than at higher levels. On windier nights, this accumulation rate is vertically uniform. Hence, extrapolation of tower profiles for estimating fluxes must be done carefully. Although uncertainties remain large, an alternate approach to the EC method is described for measuring nighttime surface CO2 fluxes under stable atmospheric conditions. | |||||
BibTeX:
@article{acevedo_inferring_2004, author = {Acevedo, O. C. and Moraes, O. L. L. and Da Silva, R. and Fitzjarrald, D. R. and Sakai, R. K. and Staebler, R. M. and Czikowsky, M. J.}, title = {Inferring nocturnal surface fluxes from vertical profiles of scalars in an Amazon pasture}, journal = {Global Change Biology}, year = {2004}, volume = {10}, number = {5}, pages = {886--894}, url = {://WOS:000221421600025 http://onlinelibrary.wiley.com/store/10.1111/j.1529-8817.2003.00755.x/asset/j.1529-8817.2003.00755.x.pdf?v=1&t=h6hx1w4i&s=66663c36af73c0fd4b0f8ea70f3c3a7cde8cf5e1}, doi = {https://doi.org/10.1111/j.1529-8817.2003.00755.x} } |
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Acevedo, O.C. and Fitzjarrald, D.R. | In the core of the night - Effects of intermittent mixing on a horizontally heterogeneous surface | 2003 | Boundary-Layer Meteorology Vol. 106(1), pp. 1-33 |
article | DOI URL |
Abstract: Intermittent breakdowns that accompany wind gusts at the surface are responsible for a large fraction of the turbulent exchange between the surface and the upper boundary layer in the core of clear nights. Vertical and horizontal structure of the breakdowns are investigated using data from a network of 26 stations in an area of 30 km x 30 km. Surface heterogeneity in the area includes complex terrain with different types of land cover. We treat the fine-scale landscape structure near sensors ('sheltering') as a separate component of heterogeneity. These features have important consequences on the spatial distribution of mean variables and surface fluxes. We found that breakdowns connect the surface layer to a higher level (level H-C). Weak wind gusts below a threshold (approximately 1.5 m s(-1)) mix the air down to the colder ground, cooling the surface layer. On the other hand, wind gusts above this threshold promote mixing with upper levels, warming the surface layer. The spatial maximum of surface temperature over the network can be used as an estimate of the temperature at H-C, allowing vertical gradients and stability to be approximated. Minimum temperature is a function of topography and sheltering. Appreciable surface fluxes at night occur primarily at high, open locations, and can be large enough there to influence area-averaged values. Surface-flux parameterizations currently used in mesoscale models were tested first by estimating fluxes at each station and aggregating, and then by forming area-averages before estimating fluxes. Results show that these formulations underestimate the average surface fluxes over a region for most of the nights. | |||||
BibTeX:
@article{acevedo_core_2003, author = {Acevedo, O. C. and Fitzjarrald, D. R.}, title = {In the core of the night - Effects of intermittent mixing on a horizontally heterogeneous surface}, journal = {Boundary-Layer Meteorology}, year = {2003}, volume = {106}, number = {1}, pages = {1--33}, url = {://WOS:000178929700001 http://www.springerlink.com/content/r321836341u18526/fulltext.pdf}, doi = {https://doi.org/10.1023/a:1020824109575} } |
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Acevedo, O.C. and Fitzjarrald, D.R. | The early evening surface-layer transition: Temporal and spatial variability | 2001 | Journal of the Atmospheric Sciences Vol. 58(17), pp. 2650-2667 |
article | DOI URL |
Abstract: On clear nights with appreciable radiative cooling, rates of change of mean quantities observed in the first 1 or 2 h after sunset are many times larger than they are subsequently until sunrise. These variations include large temperature drops, specific humidity increases, and abrupt wind speed decay. The early evening transition (EET) is dominated by vertical surface flux convergence as the turbulent mixing layer becomes confined to a shallow stable layer near the surface. Effects of surface heterogeneities are enhanced by the subsequent small eddy size, so that spatial variability of mean variables peaks during the EET. Hilltops do not experience such large variations at EET, as turbulence persists longer at those locations. Wind speed decays faster at obstructed sites, which show earlier transitions. The Richardson number increases exponentially at the EET, and the rate of exponential increase is proportional to the rate of wind decay. Qualitative aspects of the EET at a single point are resolved by a two-layer model, similar to those currently used in parameterizations of the surface exchange in mesoscale simulations. However, in order to simulate the different behaviors observed in an area as big as one grid cell in a mesoscale model, very different values of the geostrophic wind need to be imposed. A large eddy model is used to verify that the specific humidity jump and maximum cooling rate during the EET are primarily the consequence of enhanced vertical flux divergence, though in later stages of the EET, advective effects become more important. | |||||
BibTeX:
@article{acevedo_early_2001, author = {Acevedo, O. C. and Fitzjarrald, D. R.}, title = {The early evening surface-layer transition: Temporal and spatial variability}, journal = {Journal of the Atmospheric Sciences}, year = {2001}, volume = {58}, number = {17}, pages = {2650--2667}, url = {://WOS:000171133200012 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%282001%29058%3C2650%3ATEESLT%3E2.0.CO%3B2}, doi = {https://doi.org/10.1175/1520-0469(2001)058%3C2650:teeslt%3E2.0.co;2} } |
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Acevedo, O.C., da Silva, R., Fitzjarrald, D.R., Moraes, O.L.L., Sakai, R.K. and Czikowsky, M.J. | Nocturnal vertical CO(2) accumulation in two Amazonian ecosystems | 2008 | Journal of Geophysical Research-Biogeosciences Vol. 113 |
article | DOI URL |
Abstract: [1] Observations of the nocturnal vertical profile of CO2, specific humidity, temperature, and winds over a forested and a deforested site in the Amazonian region are presented. This study aims to understand better how scalars accumulate vertically at these two distinct sites at night. The measurements also provide an alternate way to determine the nocturnal fluxes under extremely calm conditions that vex the eddy covariance method. A profiling system based on a low- cost Russian CO2 sensor aboard a tethered balloon, developed for this study, is described. At the deforested site, accumulation of scalars is restricted to a 100- m thick layer, above which background concentrations of CO2 and specific humidity remain unaffected during the night. Over the forest, most of the scalars accumulate within the canopy. At both sites, accumulation and cooling rates are larger during calm periods near the surface, with the scalars escaping to upper levels during windier episodes. At the deforested site, the surface fluxes estimated from the time change of the profiles are only comparable to those observed at the nearby micrometeorological tower under windier, less stable conditions. On extremely stable nights, CO2 accumulates uniformly throughout the accumulation layer, possibly indicating convergence from the nearby forest toward the deforested region. | |||||
BibTeX:
@article{acevedo_nocturnal_2008, author = {Acevedo, O. C. and da Silva, R. and Fitzjarrald, D. R. and Moraes, O. L. L. and Sakai, R. K. and Czikowsky, M. J.}, title = {Nocturnal vertical CO(2) accumulation in two Amazonian ecosystems}, journal = {Journal of Geophysical Research-Biogeosciences}, year = {2008}, volume = {113}, url = {://000258154000002 http://www.agu.org/pubs/crossref/2008/2007JG000612.shtml}, doi = {https://doi.org/10.1029/2007jg000612} } |
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Abril, G., Parize, M., Pérez, M. and Filizola, N. | Wood decomposition in Amazonian hydropower reservoirs: an additional source of greenhouse gases [BibTeX] |
2012 | Journal of South American Earth Sciences Vol. 44, pp. 104 |
article | |
BibTeX:
@article{abril_wood_2012, author = {Abril, G. and Parize, M. and Pérez, M.A.P. and Filizola, N.}, title = {Wood decomposition in Amazonian hydropower reservoirs: an additional source of greenhouse gases}, journal = {Journal of South American Earth Sciences}, year = {2012}, volume = {44}, pages = {104} } |
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Lages, A.S., S.A.F., M., S.J.F., F., Albuquerque, S.D., Cetauro, A., Lopes, A. and Silva, M.L. | Dynamics of Heavy Metals in the Waters of Iqarape do Quarenta: The Water Body that Crosses the Industrial Hub in the Brazilian Amazon [BibTeX] |
2022 | Open Science Journal Vol. 7(2) |
article | |
BibTeX:
@article{as_dynamics_2022, author = {A.S., Lages and S.A.F., Miranda and S.J.F., Ferreira and S.D., Albuquerque and A., Cetauro and A., Lopes and M.L., Silva}, title = {Dynamics of Heavy Metals in the Waters of Iqarape do Quarenta: The Water Body that Crosses the Industrial Hub in the Brazilian Amazon}, journal = {Open Science Journal}, year = {2022}, volume = {7}, number = {2} } |