Soil erosion assessment using the erosion potential method – Case of Boussekour watershed, Central Rif, Morocco

Abstract

The human impact, combined with the geomorphological, lithological, and climatic specificities of northern Morocco, makes the soils highly vulnerable to the risk of water erosion. The primary purpose of this research is to map and assess the soil water erosion vulnerability in the Boussekour watershed, located in the Rif Mountain chain in northern Morocco, by applying the erosion potential method (EPM) developed by Gavrilović. It is an approach that involves integrating, within a Geographic Information System (GIS) environment, six parameters involved in the erosive phenomenon: temperature, rainfall, slope, soil erodibility, current erosion, and soil protection. The input data necessary for applying this model were derived from satellite images, digital elevation models (DEMs), granulometric and physico-chemical analyses of soil samples, and local rainfall data. Results show that the high erosion class (from 20 to 40 Mg∙ha−1∙yr−1) is prevalent and acts on 45% of the watershed, while the low (from 5 to 10 Mg∙ha−1∙yr−1) and very low (from 0 to 5 Mg∙ha−1∙yr−1) erosion classes account for just 6.98% and 1.44% of the area, respectively. This result demonstrates that the Boussekour watershed is profoundly threatened by soil water erosion, and an effort ought to be made to promote operative soil conservation efforts.