Landsat Sensitivity To Recovery from Burning and Clearcuts in Amazonia
A large fraction of tropical forests are undergoing forest regrowth from burning and clearcuts. Previous studies have shown that different land use practices will lead to different pathways of forest recovery. Yet studies on the rate of change of these pathways have not been presented, limiting our understanding of forest regrowth as well as the development and/or validation of forest successional models. We address this issue by using the time series from the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) that allows for the study of disturbance and regrowth. Time series of LEDAPS Landsat 5 Thematic Mapper (TM) from 1984 to 2012 of clearcuts and burning of old-growth forests in Central Amazon were selected for this study. NIR changes that were associated with forest succession displayed faster recovery over clearcuts than over burnings, consistent with observations. Since NIR is related with biomass, the rates of NIR changes could be introduced in the newly developed dynamic vegetation model, which is coupled to an Earth System Model: FATES (Functionally Assembled Terrestrial Ecosystem Simulator) to better represent forest succession and regrowth patterns. FATES currently allows for full removal of old-growth forest after clearcuts, however the speed of forest recovery is faster than the NIR band changes, and the trajectory of plant functional types needs to be improved.