Impacts of Land Use Land Cover Change in Gidabo Sub-Basin: A Literature Review of the Case of Ethiopia Rift Valley Lake Basin

Lamiso Shura, Mihret Dananto*, Petros Yohannis, and Alemu O. Aga

Abstract

In the past 50 years, there have been tremendous changes in land use pattern which exerted significant influence on land resource of the Ethiopia. This paper comprehensively analysed the primary scientific issues about the impacts of land use and land cover change on the water resource and sedimentation of Gidabo River Basin (Ethiopia. So far LULC change was studied for full basin and, upper parts of the basin from the years 1985 to 2018 by using Landsat TM and Landsat ETM+ and Landsat OLI/TIRS images. As the result, agricultural land and urban settlement is increasing and forest and grassland is decreasing in the basin. The impact of land dynamics on the hydrological response of the basin is studied up the year 2006 and reported as the surface runoff and evapotranspiration increasing staring from the year 1986 to 2006. Sediment yield and hotspot erosion area is identified based on detected land use and available measured sediment data of the basin. In this review, it is analysed that, the detected soil loss rate of the basin is significantly different form study to study and no assessment is done for the last 15 years since the measured stream and sediment flow data is limited at the year 2006. The shortage of such data and empirical estimation of sediment and flow for huge ungauged part of the basin (lower parts) have led for variation of results via analyses. Although a wide watershed interventions activity was held for the last 15 years in the watershed, no study analysed its effect so far. Hence, we would like to recommend undertaking a new study that can alleviate the variation of the previous studies upon land used land cover change, stream and sediment flow, and erosion hot spot area. Since the availability of measured sediment yield of the basin is too low, it is good to develop an empirical model that can substitute the measured sediment by using other watershed parameters.