USE OF GIS FOR THE ASSESSMENT OF PHYSIOGRAPHIC CHARACTERISTICS OF THE WATERSHED OF OUISLANE, BOUFEKRANE AND TOULAL OUEDS

This article presents the interest of the use of geographic information systems (GIS) for the characterization of the morphometric aspects, and the relief of the watershed of the three oueds studied (Ouislane, Boufekrane and Toulal), because these parameters play an important role in the flow of watersheds and in the risks of erosion. For this, we have realized several thematic maps from the SRTM images, namely: the hypsometric map, the slopes map and their exposures, the sub - basins map, the river system map and its classification. From these t hematic maps produced for the watershed studied, several physical characteristics were extracted, such as the surface, the perimeter, the Gravelius compactness index, and the equivalent rectangle. These indices show that the sub - basins studied have an elon gated shape which causes a delay in the delivery of water to the outlet during the flood period