Soil erosion risk assessment for prioritization of sub-watershed: the case of Chogo Watershed, Horo Guduru Wollega, Ethiopia

Mis-management of agricultural land and overexploitation of natural resources like forest and grasslands accelerated the problem of soil erosion in developing countries, where agriculture plays an important role in the economy. Moreover, the rapid population growth and advancement in science and technology increased the risk of soil erosion and its associated problems. The overexploitations of natural resources by the local communities for the sake of agricultural expansions accelerated the problems of soil erosions in the highland areas of Ethiopia. Thus, soil erosion risk assessment is crucial to influence policy makers for mitigation measures. In the present study, soil data, satellite image, ASTER DEM, and rainfall data were collected from different sources to estimate the amount of soil loss per year in the study area. The Revised Universal Soil Loss Equation (RUSLE), and Geographic Information Systems (GIS) were used to estimate the mean annual soil loss in the study area. Results showed that the total annual soil loss in the sub-watershed was 377.26 tons hectare per year. The annual soil loss of Chogo watershed ranging from 0.00 at plain surface to 786.969 tons hectares per year. The reported results can support decision-makers for soil erosion risk prevention strategies and conservation measures.

Automated summary

This study estimated the annual soil loss in the study area through soil data and satellite images, revealing that soil erosion problems are mainly caused by mis-management of agricultural land and overexploitation of natural resources. The importance of soil erosion risk assessment was emphasized to influence policy makers in implementing effective mitigation measures.