Mapping and monitoring land cover in Acre State, Brazilian Amazônia, using multitemporal remote sensing data

This paper presents the use of multitemporal remote sensing data for monitoring land cover changes in Acre State, Brazilian Amazonia. The 2000 Landsat ETM+, the 1990 Landsat TM, and 1980 Landsat MSS were used. The 2005 and 2007 MODIS images were also used to map deforestation occurred during the recent years and to map burned areas occurred in the 2005 dry year. The Landsat and MODIS images were converted to vegetation, soil, and shade fraction images. Then land cover maps were obtained by digital classification of these fraction images. The deforestation increased 7, 114 km² from 1980 to 1990, 4, 900 km² from 1990 to 2000, and 3, 258 km² from 2000 to 2007. It also showed that about 2, 815 km² of regrowth areas were observed in the 2000 ETM+ images. The analysis of MODIS images showed that 3, 700 km² of deforested areas and 2, 800 km² of forested areas were burned in Acre State in 2005. These information are critical for regional and global environmental studies and for efforts to control such burning and deforestation in the future.