Estimation of Soil Loss Using Revised Universal Soil Loss Equation and Determinants of Soil Loss in Tiro Afeta and Dedo Districts of Jimma Zone, Oromiya National Regional State, Ethiopia

Abstract

Soil erosion is the principal cause of land degradation and a major constraint to agricultural development in developing countries like Ethiopia. Tackling the problem of soil erosion requires understanding of the rates of soil loss. In this study, an attempt is made to quantify soil loss due to water erosion at plot level in Dedo and Tiro Afeta district areas. The amount of soil loss was predicted using RUSLE model and adapted to Ethiopian conditions. Primary data were collected from 150 randomly selected farm households, managing about 750 plots through individual interviews using semi-structured questionnaires. The result of the study revealed that, the lowest soil loss is estimated on flat plains (<2% slope) to be about 1.59 t haG1 yearG1 , which is less than the minimum tolerable soil loss (2 t haG1 yearG1 ) for the country. However, the highest soil loss is from steep slopes (up to 35%) at about 31.7 t haG1 yearG1 , about twice the maximum tolerable soil loss (18 t haG1 yearG1 ). The average soil loss rates at cut-off point ranges on average from 1.59-31.7 t haG1 yearG1 . In order to reverse the soil loss into fertile soil, the farm households need to have a minimum of formal education for using soil and water conservation technologies and guaranteeing the sustainability of soil loss for enhancement of productivity of each plot. The study results suggest that selecting priority intervention areas and rehabilitating soil loss management strategies should consider the socio-economic characteristics and plot specific characteristics of the farm households.