Mapping of soil sensitivity to water erosion by RUSLE model: case of the Inaouene watershed (Northeast Morocco)

Abstract

The sources of land degradation in many watersheds are runoff and erosion. In order to delay this degradation resulting in the loss of soil fertility, a system for its quantification needs to be established. Erosion severely impacts our natural capital and requires several studies and prevention and management steps. This research focuses on validating the revised universal soil loss equation (RUSLE) method through evidence from remote sensing (RS) and the Geographic Information System (GIS) in the watershed of the Inaouene river upstream of the Idriss 1st dam in the Taza region (northeast of Morocco). In this context, the approach adopted was performed, consists in combining the revised universal soil loss equation (RUSLE) to quantify erosion and GIS to spatialize the factors responsible for water erosion and soil loss (climate, soil, vegetation, and topography) GIS to produce a map of erosion risk. The results achieved show that the Inaouene watershed is characterized by an average climatic aggressiveness, a sparse vegetation cover without any safeguards, moderate to high erodible soils with a maximum ranging from 50 to 150 t/h/year. Topography characterized by high (50%) to moderately broken reliefs. The human intervention remains the most mattering factor in the embrittlement and the accentuation of the soils vulnerability for erosion for every dominant natural factor. The results of this study could be of use in prioritizing areas for soil conservation measures and watershed development and management. It is a tool for decision-makers, planners, and decision-makers in soil and water conservation decision-making to implement anti-erosion strategies to reduce the impact of erosion.