Project Funding: 2012 - 2015

NRA: 2011 NASA: Terrestrial Ecology   

Funded by NASA

Abstract:
The recent expansion of pastures and agricultural monocultures has resulted in 730,000 km2 of the Amazon Basin being deforested. Despite recent declines in the rates of forest clearing, the deforested area of the Amazon Basin is projected to jump from ~18% today to as much as 40% by 2050 as the global demand for agricultural commodities continues to rise. Influences of land use change (LUC) on ecosystem processes are thus expected to become increasingly important for the region; forest conversion into pastures and crops tends to reduce evapotranspiration and albedo, altering the regional energy balance in ways that increase surface temperature and alter precipitation patterns. Until recently, our ability to quantify these LUC effects on ecosystem processes was constrained by the lack of spatial-temporal information that captured the complex land use transitions in Amazonia. However, with the high temporal resolution and decade-long span of the MODIS dataset, we have new opportunities to not only map these complex dynamics, in spatial as well as temporal detail, but also to quantify their consequences for the regional energy balance. Here we will use MODIS products combined with a dynamic vegetation model to quantify the influences of LUC on the albedo and latent and sensible heat fluxes in the southeastern Amazon, where deforestation rates are greatest. The overarching questions we address in this study are: How does LUC (historical and future) affect the regional energy balance and partitioning in Amazonia? How do these effects compare with those associated with changes in the radiative forcing from increased atmospheric CO2 concentration? To do so, we will use existing MODIS products to (i) map the spatial-temporal patterns of LUC from 2000-2012 in the Brazilian states of Mato Grosso and Pará and (ii) quantify LUC effects on the local and regional energy balance (latent heat, sensible heat, and albedo). This information will serve as the basis for predicting how future (2012-2050) land use transitions will alter the energy balance, using spatial models that simulate deforestation, cattle ranching, and soybean expansion. Future radiative forcing associated with these changes in land use will then be compared to the radiative forcing caused by increased atmospheric CO2, providing an estimate of future net radiative forcing in the region. Finally, we will scale up the analysis to the entire Amazon Basin, simulating combinations of several LUC and CO2 emissions scenarios. Global demand for agricultural products is expected to increase substantially in the next few decades and tropical regions such as Amazon are the only remaining areas with available land to meet these demands. This increased incentive for deforestation may be exacerbated by proposed changes in the Brazilian forest code, which currently requires private landowners to conserve substantial tracts of forest. The proposed research will provide critical insights into how these changes may impact radiative forcing and, ultimately, alter regional and global climate and carbon cycles.

Publications:

Arantes, A. E., Ferreira, L. G., Coe, M. T. 2016. The seasonal carbon and water balances of the Cerrado environment of Brazil: Past, present, and future influences of land cover and land use. ISPRS Journal of Photogrammetry and Remote Sensing. 117, 66-78. DOI: 10.1016/j.isprsjprs.2016.02.008

De Faria, B. L., Brando, P. M., Macedo, M. N., Panday, P. K., Soares-Filho, B. S., Coe, M. T. 2017. Current and future patterns of fire-induced forest degradation in Amazonia. Environmental Research Letters. 12(9), 095005. DOI: 10.1088/1748-9326/aa69ce

Dias, L. C. P., Macedo, M. N., Costa, M. H., Coe, M. T., Neill, C. 2015. Effects of land cover change on evapotranspiration and streamflow of small catchments in the Upper Xingu River Basin, Central Brazil. Journal of Hydrology: Regional Studies. 4, 108-122. DOI: 10.1016/j.ejrh.2015.05.010

Gouvello C, Soares Filho BS, Nassar A (coord.) 2010. Estudo de Baixo Carbono para o Brasil: uso da terra, mudanças do uso da terra e florestas - Relatório de Síntese Técnica. Washington, US: Banco Mundial. Disponível em: http://siteresources.worldbank.org/BRAZILEXTN/Resources/Brazil_LowcarbonStudy.pdf.

Panday, P. K., Coe, M. T., Macedo, M. N., Lefebvre, P., Castanho, A. D. D. A. 2015. Deforestation offsets water balance changes due to climate variability in the Xingu River in eastern Amazonia. Journal of Hydrology. 523, 822-829. DOI: 10.1016/j.jhydrol.2015.02.018

Silverio, D. V., Brando, P. M., Macedo, M. N., Beck, P. S. A., Bustamante, M., Coe, M. T. 2015. Agricultural expansion dominates climate changes in southeastern Amazonia: the overlooked non-GHG forcing. Environmental Research Letters. 10(10), 104015. DOI: 10.1088/1748-9326/10/10/104015

Soares-Filho BS, Lima L, Bowman M, Viana L, Gouvello C. 2012. Challenges for a low carbon agriculture and forest conservation in Brazil. Sustainability Report. IADB. Washington. Disponível em: http://www.iadb.org/sustainability/soares

Soares-Filho, B., Rajao, R., Macedo, M., Carneiro, A., Costa, W., Coe, M., Rodrigues, H., Alencar, A. 2014. Cracking Brazil's Forest Code. Science. 344(6182), 363-364. DOI: 10.1126/science.1246663

Soares-Filho, B., Rajao, R., Merry, F., Rodrigues, H., Davis, J., Lima, L., Macedo, M., Coe, M., Carneiro, A., Santiago, L. 2016. Brazil's Market for Trading Forest Certificates. PLOS ONE. 11(4), e0152311. DOI: 10.1371/journal.pone.0152311

Soares-Filho, B., Rodrigues, H., Follador, M. 2013. A hybrid analytical-heuristic method for calibrating land-use change models. Environmental Modelling & Software. 43, 80-87. DOI: 10.1016/j.envsoft.2013.01.010

Spera, S. A., Galford, G. L., Coe, M. T., Macedo, M. N., Mustard, J. F. 2016. Land-use change affects water recycling in Brazil's last agricultural frontier. Global Change Biology. 22(10), 3405-3413. DOI: 10.1111/gcb.13298

2015 NASA Carbon Cycle & Ecosystems Joint Science Workshop Poster(s)

• Deforestation offsets water balance changes due to climate variability in the Xingu River in eastern Amazonia   --   (Prajjwal K Panday, Michael T Coe, Marcia N Macedo, Paul Lefebvre, Andrea Castanho)   [abstract]
• Agricultural expansion reduces net radiation and water recycling in Amazonia   --   (Divino V Silvério, Paulo M Brando, Marcia N Macedo, Pieter S Beck, Michael T Coe)   [abstract]

More details may be found in the following project profile(s):

• NASA Terrestrial Ecology (TE) Project Profile