Land-use and land-cover dynamics and their drivers in the central highlands of Ethiopia with special reference to the Lake Wanchi watershed

Land-use and land-cover (LULC) changes have been recognized universally as fundamental constituents of global biodiversity and ecosystem services change driver. The objectives of this study were analyzing the spatial and temporal LULC dynamics over the past 44 years and identifying the major drivers of these changes. It was conducted in the central highlands of Ethiopia at the social-ecological Lake Wanchi watershed. The study triangulated data from Landsat images of four different time series, ground verifications, focus group discussions, key informants interview, and quantitative analytical approach. The Landsat imageries were processed and analyzed using ArcGIS 10.3 software. Supervised classification was executed using the maximum likelihood technique. The non-quantifiable data were analyzed using qualitative descriptions and the quantitative analytical approach was used to rank the degree of LULC change drivers. About 62% of the land area in the study watershed experienced LULC conversions. Wetlands, forest-cover, shrub-cover, and water body converted (declined) annually at a rate of 3.3%, 1.4%, 1.3% and 0.6%, respectively. Croplands, bare lands, agroforestry, and settlements, expanded annually at the rate of 10.2%, 5.7%, 2.6% and 2.1%, respectively. Agricultural activities, wood extraction, settlement expansion, and infrastructure constructions were proximate LULC change drivers, while, demographic changes, community conflict, and land tenure policy were the underlying change drivers. To mitigate the rapid LULC changes and safeguard the social-ecological benefits at the local watershed and distant downstream systems of Lake Wanchi, rehabilitation of the watershed specifically, the natural vegetation covers and environmentally sensitive areas, through the application of integrated watershed management strategies is critically important.