Integrated impact of land use/cover and topography on hydrological extremes in the Baro River Basin

Hydrological extremes can be influenced by climatic inputs (e.g., rainfall), but are controlled by topographical and anthropogenic factors. Note that the combined effect of topography and land use/cover on hydrological extremes is not fully explored and requires further research. This study considered five watersheds in the Baro River basin with varying topographic and land use/cover combinations to investigate the integrated impacts of topography and land use/cover on the hydrological extremes. The selected watersheds were classified as forest-dominated (i.e., Uka, Sor, and Gumero watersheds) and agriculturally dominated (i.e., Meti and Keto watersheds), as well as flat-to-gently sloped watersheds (Uka and Gumero) and moderate-to-sloped watersheds (Sor, Meti, and Keto). Google Earth Engine (GEE) was used to analyze the land-use/land-cover change from 1990 to 2018, and the topographical variables were quantified using the GIS tool. Finally, the elasticity approach was used to estimate the sensitivity of low and peak flow to the individual and combined impacts of land use/cover and topography. Generally, the results revealed that both low and peak flows were more sensitive to sloped watersheds with forest land-cover types, with elasticity's of 0-2.6% for low flow and 0-4.6% for peak flow, respectively.