MODELING AND ASSESSMENT OF THE IMPACT OF LAND USE IN THE WESTERN RIF REGION, MOROCCO, ON WATER QUALITY

Abstract. The Western Rif is a rural area characterized by rock extraction and agriculture. As a result, the surface of the land in the region is exposed to different sources of contamination which alters the quality of the soil. Leaching of the soil and runoff to surface water may impact the quality of surface water used by local people. A mapping of the land use by GIS of an area located at the level of the western Rif was carried out then an analysis of the interactions between the uses of the land; the practices, the quality of the surface layer of the soil and the quality of the water were made. Thanks to the processing of satellite images and to samples on the ground and assays of the physic-chemical parameters of soils and water (T °, pH, MES, turbidity, Nitrate, nitrite, phosphorus, nitrogen, etc.). The results of these analyzes revealed that these activities lead to an alteration in the quality of the surface layer of the soil, its characterization of which changes depending on the land use. Surface water is endowed with the components identified in the soil. This reveals that land use has generally negative physical and chemical impacts on surface waters.