Anthropogenic pressure in East Africa-Monitoring 20 years of land cover changes by means of medium resolution satellite data

The East Africa IGAD (Intergovernmental Authority on Development in Eastern Africa) region with its great variety of ecological regions experienced major changes during the last decades. This study assesses and quantifies the land cover dynamics in the region by applying a systematic sampling of medium resolution Landsat and DMC Deimos imagery. 445 samples covering about 3% of the study area taken as a box of 20 km x 20 km around each 1 degree latitude and longitude intersects are processed and analyzed. Statistical estimates of land cover change are produced by means of an automatic object-based classification in seven broad classes for the years 1990-2000 and 2000-2010. Figures of change for the East Africa IGAD region are presented and land cover change processes such as loss of natural vegetation and increase of agriculture areas are analyzed. Results highlight the geographical distribution of land cover dynamics and show a 28% increase in agriculture area over the analyzed 20-year time frame. The yearly agriculture area increase rate is around 1.4% for both assessed decades, however a strong increase in yearly deforestation rate - from 0.2% in the first period to 0.4% in the second period - has been observed. These figures are discussed within the context of the drivers of changes and the resulting impact to the natural ecosystem. (C) 2013 Elsevier B.V. All rights reserved.