Modeling the impacts of land use and land cover dynamics on hydrological processes of the Keleta watershed, Ethiopia

Abstract

Natural resource degradation resulting from inappropriate land use and subsequent hydrological change is one of the key problems threatening environmental welfare and sustainable development. This study investigates the changes in the hydrological process in response to the land use and land cover (LULC) dynamics of the Keleta watershed, Awash River basin, Ethiopia using the Soil and Water Assessment Tool (SWAT) model. The model was calibrated and validated using monthly observed stream flow data for the baseline year (1985) and performed well (NSE ≥ 0.74, RMS ≤ 0.51, and PBIAS ≤ 15.3). An overall increase in the amount of surface runoff and base flow (10.4%) and (0.6%) and a decline in groundwater flow (3.5%) were observed in 2010 compared with the baseline year (1985). The trend of increasing surface runoff and declining groundwater flow due to LULC changes has wider implications for environmental and water resource development. This is expected to exert a substantial adverse impact on ecosystems, hydraulic structures such as dams, reservoirs, and irrigation canals, and rural livelihoods unless appropriate integrated landscape management is implemented.