Erosion Sensitivity Mapping Using GIS-Based Multicriteria Analysis – Case Study of the Semiarid Macta Watershed, North-West of Algeria

Abstract

The exponential rise in the natural risk related to the soil erosion and important impacts on the human activities threatening the biological richness of different regions in Macta watershed located at the northwest of Algeria. This serious and complex situation has been an environmental concern in Algeria. Soil erosion is mainly due to a combination of factors such as climate (rainfall), topography, vegetation cover, type of soil and land use (agricultural activities). The study aimed to develop a methodological approach, based on the combined use of geographic information system (GIS), remote sensing and multicriteria analysis method (MCA), dedicated to the soil erosion sensitivity mapping. The different factors are involved in a geographical database as layers in order to make it easier to implement the decision aid dataset such as alternatives and criteria. The obtained results show that the most threatened areas by the soil erosion phenomena are situated, in general, in the south and the east. Areas of high vulnerability correspond to some sub-watershed with different degrees, i.e., Mezoua, Taria, Mekerra, and Fergoug.