Land use/land cover changes (LULCCs) are major environmental challenges in various parts of the world and are a continuing phenomenon (including Ethiopia) and adversely affecting ecosystem services. Thus, understanding the rate and process of change is, therefore, basic for managing the environment. The Central Rift Valley (CRV) of Ethiopia is a closed basin where questions on natural resources have strongly increased over the past decade as a result of over use of the resources: a clear symptom is the declining trend in the water level of the terminal Lake Abjiata. This study was aimed to analyze LULC changes on the ecological landscape of Ethiopia CRV from 1985 to 2015 based on multi-temporal Landsat Thematic Mapper plus Operational Land Imager (TM + OLI) images. Change analysis was carried out using post classification comparison in GIS environment and nine LULC changes were successfully evaluated. The classification result revealed that in 1985, 44.34% of the land was covered with small scale farming followed by mixed cultivated/acacia (21.89%), open woodland (11.96%), and water bodies (9.77%). Whereas for the same study year open grazing land, forest, degraded savannah and settlements accounted the smallest proportion. Though the area varied among land use classes, the order of proportion occupied by the LULC types in the study area remained the same in 1995 and 2015. The change result shows that an increase in small and large scale farming, settlements and mixed cultivation/acacia while a decrease in water bodies, forest and open woodlands. More specifically, Lake Abjiata showed a progressive decline mainly related to anthropogenic factors. Generally, analysis of the 30-year changes revealed that about 86.11% of the land showed major changes in land use/cover. Therefore, based on the DPSIR framework analysis, an integrated land use and development planning and policy reform are suggested for sustainable land use planning and management.
Keywords: CRV, Ethiopia, Landsat images, Lake, land use/cover