Climate change and land degradation in Africa: a case study in the Mount Elgon region, Uganda

摘要

The aim of this study is to estimate and compare soil erosion,in the Mount Elgon region,eastern Uganda,during the last decade.Possible trends and changes in erosion are linked to precipitation/climate change as well as changes in land cover.Two different versions of the Revised Universal Soil loss Equation(RUSLE)are implemented and compared,one using slope length and the other using flow accumulation to estimate the slope length and steepness factor(LS).Comparisons of the modeled soil erosion vs.field data indicate that RUSLE based on flow accumulation is preferable.The modeling is carried out for the years 2000,2006,and 2012,and is based on ASTER remotely sensed data,digital elevation models,precipitation data from the study area,as well as existing soil maps.No significant trends in estimated soil erosion are found to be present during the last decade.Over exploitation of land is probably compensated by improved agricultural management and no significant increase in precipitation.Even if there are reports of more intense and increasing amounts of rainfall in the area,this could not be verified,neither through the analysis of climate data,nor by trends in the estimated soil loss.