The present work aims to analyze the ground cover, of the Belo Monte Dam complex region using NDVI (Normalized Difference Vegetation Index), calculated from TM / Landsat 5 and OLI / Landsat 8 images from 2008 to 2018. The use of images over the 10-year period can continuously identify trends in the pixels due to the change in land use. The mapping consisted of a polygon (buffer) on each side of the Xingu River, the images obtained during the dry period, in the Imaging Division of the United States Geological Survey (USGS). The scenes were processed and the thematic maps generated in ArcGIS® 10.2.2. and the NDVI tool was applied for the mapping of areas and then a grid was generated with the processed values, than the creation of thematic classes based on intervals of index values, for the generation of thematic images, with associated defined value intervals to a color scale. The reduction in NDVI values in the years 2008, 2009, 2016 and 2017 shows the direct influence of the decrease in vegetation due to deforestation. It is checked that during the time series, that from 2013 to 2016 there was a constancy in the NDVI values, indicating that in those years there were no major losses of plant biomass. Thus, the application of the index shows an efficiency when analyzing the behavior of the vegetation made it possible to verify a huge loss of plant biomass and increase of exposed soil due to the implantation of the Belo Monte Dam.
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