Assessing Environmental Sensitivity Areas to Desertification in Eastern Algeria using Mediterranean Desertification and Land Use “MEDALUS” Model

Abstract

The sensitivity map to desertification of Eastern Algeria (Aures region) has been elaborated by the crossing of four thematic layers (vegetation, climate, soil and the socioeconomic states), which have the main impact on the evolutionary process of desertification. The followed methodology is inspired from the desertification model MEDALUS (Mediterranean Desertification And Land Use), which use qualitative index to define the land zones sensitive to desertification. Cartographical information of vegetation, climate variation, soil and the socioeconomic states obtained from cartographic data were transformed to numerical data then seized on, structured and managed by an algorithm dedicated to a geographical information system. Moreover, ALSAT-1 satellite images, geologic and soil maps were used as main sources for calculating the index of Environmental Sensitivity Areas (ESAI) for desertification. Besides, the main goal of this study is to identify places with different sensitivity to land degradation in Aures region (East Algeria) by means of a modeling approach developed in the European Commission funded MEDALUS project, which identifies such areas on the basis of an index (ESA index, Environmental Sensitive Area index) in which environmental quality (climate, vegetation, soil) as well as anthropogenic factors (management) are included as weighted layers.