The use of Landsat time series for identification of forest degradation levels in the eastern Brazilian Amazon (Paragominas)

Forest degradation is the reduction of the capacity of a forest to provide goods and services. Degraded forests in the Brazilian Amazon region are dominant in the pioneer front landscapes where the economic growth and agricultural expansion has converted the primary forest to a mosaic of pastures, crop land and forests in various stages of degradation. Understanding spatial structure and temporal trajectories of forest degradation is important to support forest conservation and management, aiming at reducing greenhouse gas emissions, retrieving biomass, biological diversity and sustainable economic development. We present a method to evaluate and map different levels of forest degradation in Paragominas a county in the Arc of Deforestation in the Brazilian Amazon. We used Landsat time series (2000-2015) and the CLASlite software to calculated the fractional cover maps with three bands of Photosynthetic Vegetation (PV), NonPhotosynthetic Vegetation (NPV) and bare Soil (S) for each year and to produce annual maps of forest degradation. We analyzed the variance of each CLASlite band (PV, NPV, S) along the 2000-2015 period. Field observations of degraded forests, based on indicators of forest strncturc were used for the validation. The results showed that the CLASlite bands variances arc relevant indicators of the fore st degradation processes. (Résumé d'auteur