Integrating Sentinel-2 Data and PAPCAR Model to Map Water Erosion: Case of Beni Boufrah Watershed

Abstract

Water erosion causes significant economic losses linked mainly to the silting up of dams and losses in soil productivity, these consequences will increase if soil and water conservation actions associated with development actions are not undertaken. The present work aims to evaluate the water erosion in the basin of the Beni Boufrah located in the Northern part of Morocco. The hierarchy of this basin in plot according to the degrees and the tendencies of the erosion was made using the qualitative PAP/CAR approach (Programme d’Actions Prioritaires/Centre d’Activités Regionales) which is based on the integration of the factors influencing the water erosion, such as the slope, lithology and/or pedology, vegetation cover and land use. This work was conducted in three stages, the first one being predictive based on the analysis of the natural factors influencing water erosion and the processing of databases of developed maps. The second so-called descriptive stage is based on the mapping of different forms and processes of soil loss that occur in the study area. The last step, it allows the integration and the combination of the results of the two previous steps. Its purpose is to provide a precise cartographic product that reflects the reality of the state of soil degradation and the future evolution of erosion. The consolidated erosion map shows that more than half of the basin area (53%) is affected by medium-level erosion, 13% is affected by high erosion level, and 15 % is affected by low-level water erosion. Low-intensity erosion occurs along the river in areas where the slope and lithology favour runoff. The trend map is the final result of the integration phase, it describes erosion trends in the different parts of the basin and is, therefore, a tool to guide decisions on land use planning and tillage methods to limit the risk of water erosion in the basin.

Keywords: Oued Beni Boufrah, water erosion, PAP/CAR, erosive states, erosion trend.