Metabolism and phenology of Amazon rainforests significantly influence global dynamics of climate, carbon, and water, but remain poorly understood. Comparisons of models with carbon fluxes, and closely coupled water fluxes, suggest that in the Amazon basin the dynamics of wet-dry season differences in carbon and water exchange typically are not well represented by general circulation and ecosystem models.
Our goal is to link local to regional scale carbon flux measurements from flux-towers and forest plots to satellite data (Moderate Resolution Imaging Spectroradiometer, MODIS), and to rigorously test remote-sensing based predictions of Amazonian carbon dynamics. We are working on indices of seasonal and inter-annual variation in driving variables (e.g. sunlight and precipitation), and the associated response of key processes (e.g. carbon fluxes and foliar activity) on a regional basis (Huete et al., 2006; Saleska et al., 2007). We look at seasonality and inter-annual variability because ecosystem response to seasonal forcing provides a window onto mechanisms that also control their long-term responses and structure.
Huete, A.R., Didan, K., Shimabukuro, Y.E., Ratana, P., Saleska, S.R., Hutyra, L.R., Yang, W., Nemani, R.R., Myneni, R., 2006. Amazon rainforests green-up with sunlight in dry season. Geophys. Res. Lett. 33.
Saleska, S.R., Didan, K., Huete, A.R., da Rocha, H.R., 2007. Amazon Forests Green-Up During 2005 Drought. Science 318, 612.
Kenia Wiedemann, Post-doctoral Fellow, University of Arizona; Natalia Restrepo-CoupÃ©, Research Fellow, University of Technology, Sydney, Australia; Alfredo Huete, Professor, University of Technology, Sydney, Australia; Piyachat Ratana, Research Fellow, University of Technology, Sydney, Australia; Yosio Edemir Shimabukuro, Instituto Nacional de Pesquisas Espaciais â€“ INPE.