Évaluation par analyse multicriteres de la vulnérabilité des sols a l'érosion : cas du bassin versant de l'Isser – Tlemcen – Algérie |Full article

The drainage basin of Isser, space weakened by the periods of drought and characterized by exposures of marls and very fragile clays, prese nts a high sensitivity to erosion. In addition to the deterioration of the quality of water, the eros ion phenomenon in this zone presents risks of depletion of topsoil, loss of fertility, loosening of plants and pollution by pesticides dissolved in surface water runoff. The erosion results from the conjunction of many pe rmanent factors (as those related to the soil or to the topography), that are evolving o r presenting a random character (such as precipitations) and intervene at different levels i n erosion processes. The purpose of the work is to produce a map of soil vulnerability to the erosion by integrating field data, different thematic maps and satellite images through GIS solution. This map sho uld be a basis for the development of the anti-eros ive land use plan adapted to the specific context of th e drainage basin of Isser. We do integrate four factors which determine the erosion: precipitations , topography, lithology, and vegetation cover. For combining these different factors, we use a cut ting space in regular meshes. The resulting map of the vulnerability to the erosion should reveal homo geneous areas for priority interventions.