Assessment of Soil Loss by Water Erosion at a Large Basin Scale: A Case Study of the Cheliff Basin, Algeria

Water erosion is the main driver of soil loss in semi-arid mountainous regions, particularly in Algeria. Identifying the spatial distribution of erosion is a crucial first step, providing decision-makers with essential information to develop effective mitigation strategies. The main objective of this study is to apply the Revised Universal Soil Loss Equation (RUSLE) to estimate soil loss and rank the sub-basins of the Wadi Cheliff Basin (43,750 km²). Different geographical and non-spatial data sets have been employed to develop different thematic layers of the RUSLE factors such as: rainfall erosivity factor (R), soil erodibility factor (K), topographic factor (LS), crop management factor (C), and support practice factor (P). The soil erosion in the Wadi Cheliff basin in the current study ranges considerably from a minimum of 0 to a maximum of tons per hectare per year. Estimated average annual erosion rates were 0.70 t/ha in autumn 2017 and ranged between 0.00 and 0.57 t/ha in spring 2018. Information on soil erosion patterns at the sub-basin level can guide the planning of effective conservation practices. Such information is helpful for the implementation of erosion control practices and improving overall environmental management in the basin.