Land use and land cover change in Ameleke Watershed, South Ethiopia

Abstract

This study investigated the land use and land cover change at Ameleke watershed, middle catchment of Gidabo River, South Ethiopia that occurred from 1986-2006. Landsat TM of 1986, Landsat ETM+ of 2000 and SPOT of 2006 were used to produce land use and land cover maps of the watershed. A pixel-based supervised image classification through decision rule of maximum likelihood classifier algorithm was used to map land use and land covers on ERDAS Imagine 8.6.  For land use and land cover maps of 1986, 2000 and 2006, error matrixes were produced and have an accuracy assessment of 80%, 85% and 85.71% respectively. Focused group discussions and key informant interviews were also used for land use and land cover reconstruction. The result showed from 1986 up to 2006, cropland and mixed cover increased from 23.33% to 31% and 7.26 to 15.68% of the watershed respectively. In contrast grass lands and shrub lands decreased from 25.9% to 14.96% and 30.3% and 24.25% of the watershed respectively in 1986 to 2006. There was also an increasing trend on agroforestry while there was a decreasing trend on riverine forests. This study recommends further assessment and monitoring of spatial and temporal based land use and land cover change at homestead level having high resolution satellite images.

Keywords: land use and land cover change, Ameleke watershed