Soil loss estimation using the revised universal soil loss equation and a GIS-based model: a case study of Jijel Wilaya, Algeria

The wilaya of Jijel with sylvo-agricultural vocation is considered to be the most degraded region of northern Algeria and the Maghreb, which makes it very sensitive to water erosion phenomena. To characterize the stage of physical degradation of the study area, this study attempts to estimate and map potential soil loss of the wilaya using the revised universal soil loss equation (RUSLE). In order to achieve this, our methodology was to overlay data representing the various factors of the RUSLE equation. The result highlighted the high erosivity of the study area where soil loss greater than 100 t/ha/year occupies 68.63% of its area with a loss rate average of 286.4 t/ha/year and a total loss of 688,219 t/year. These high rates are due to a very steep terrain, an aggressive climate, a high soil erodibility, and a vegetation cover degraded by repeated summer fires. Remote sensing data used in a GIS allowed the quantification of potential soil loss and the determination of priority protection areas on a regional scale; this was a great benefit for this sector as it has a high proportion of steep slope areas that makes it almost inaccessible.