Approche, de la gestion intégrée du littoral et des bassins fluviaux « GILIF »

Abstract

Like many coastal areas around the world, Skikda coastline is subject to disturbances that threaten its balance at various levels; ecological, sedimentary, sociological, and economic. With 160 km of coastal lineage, a very strong coastal dynamics, and a great conflict of use, Skikda coastline is a complex system at the interface between land and sea. The watershed is a sedimentary source of supply necessary for coastal balance, and any activ ty that contributes to the disruption of this supply will lead to a morphodynamic imbalance. This observation was a starting point for a reflection on the space that must be retained to manage and protect Skikda coastline. The main objective of this disertation is to strengthen geomorphological knowledge in a context based on the link between the watershed and the coastline. In order to achieve this objective, two approaches were used. A systemic approach based on the concept of system, integrating the upper land which is the watershed with the coastline;and a morphodynamic approach that relies on the digital processing of satellite images (Landsat 8) and aerial photographs (1960, 1970, 1988, 2002) through the application of Geographic Information Systems. The results obtained in the two areas studied, which are the Saf-Saf watershed and the mouth, demonstrate a regressive situation of the mouth and its nearby beach L’arbi ben Mhidi. The interpretation and discussion of these results allow to identify the factors that explain this morphological evolution, such as the impact of sedimentary retention at the dam level, deve lopments on the shore, and weather-marine forcing.