Using RUSLE and GIS for the soil loss assessment in arid regions: The case of the Ain Sefra catchment in the Ksour Mountains, Algeria

The loss of soil quality due to erosion is a global problem, particularly affecting natural resources and agricultural production in Algeria. In this study, the Revised Universal Soil Loss Equation (RUSLE) is applied to estimate the risk of water erosion in the Ain Sefra arid watershed (Algeria). The coupling of this equation with Geographic Information Systems (GIS) allows to assess and map the soil loss rates. The land erosion is influenced by many control variables, such as the topographic factor of the terrain and the length of slope (LS factor), rainfall erosivity (R factor), sensitivity of soil to erosion (K factor), presence of vegetation (C factor) and the antierosion cultivation techniques (P factor). To calculate the average annual soil loss, these five factors were considered and multiplied in the RUSLE Equation. The result shows that the average rate of soil loss is estimated at about 5.2 t·ha–1·y–1 over the whole watershed. This study is the first of its kind in the region and aims to assess the soil loss caused by water erosion processes in this arid zone. Consequently, it is essential to take real intervention measures in these upstream areas in order to combat this scourge, based on priorities ensuring the sustainable management of natural resources in the study area.