Modelling the spatiotemporal dynamics of land susceptibility to desertification in Algeria

Abstract

Desertification is a significant environmental and socioeconomic issue that requires monitoring and early detection. In this context, holistic studies are more useful than localized ones in addressing this issue. In this study, we used the desertification sensitivity index (DSI) to pinpoint regions of Algeria that are at risk of desertification and to examine significant shifts in the sensitivity of land to desertification between 2000 and 2020, as well as the primary drivers of these shifts. Unlike the standard Mediterranean Desertification and Land Use (MEDALUS) approach, which uses equal weighting of parameters and quality indicators to construct the environmental sensitivity areas, the DSI applies statistically generated weights. Our results showed that approximately 106,000 km2 of the non-desert area was extremely susceptible to desertification in 2000, 83,200 km2 in 2010, and 98,200 km2 in 2020, with critical zones mainly located in the High Plains (steppe rangelands). Our analysis revealed that climate and vegetation quality indicators were the main drivers of the DSI, which showed a nonlinear trend during the study period. The analysis of changes in land sensitivity to desertification revealed that most of the changes were negative and occurred in the High Plains, as well as certain areas of the Tell Atlas Mountain ranges and the littoral fringe. However, some positive changes occurred due to the establishment of new forest plantations and croplands. The results provide a comprehensive overview of the risk of desertification in Algeria and its main drivers and can serve as a scientific basis for the development and implementation of necessary measures to interrupt and combat this destructive environmental phenomenon.