Evolution of Mediterranean forest ecosystems. Case of the cork oak forest Tlemcen – Algeria

Abstract: Forest degradation poses a serious threat to the stability of the global climate because forests store more carbon than any other terrestrial ecosystem. Forest cover is one of the most important topics in global environmental discussions and negotiations. It is therefore essential to have reliable and up-to-date information on the status of forest resources. In North Africa, there is a broad consensus on forest decline, but available information on the extent and rate of degradation is far lower than needed. In this study, the goal is to fill a lack of information in a poorly studied area with limited data availability by determining the extent of changes in forest cover. The present study used the example of the cork oak forest of Tlemcen, North West Algeria, to provide spatially explicit and up-to-date information on forest cover changes. Land use and land cover maps of 1989, 1999, 2009 and 2019 were classified using Random Forest Algorithm in R software and changes assessed. The results revealed that the sparse vegetation was the dominant land cover at the end of the study period, although it decreased from 71.25% in 1989 to 65.24% in 2019. The lowest coverage was water body from 0.47% in 1989 to 0.18% in 2019. Sparse vegetation (-6.01%) and dense forest (-3.22%) experienced a major decline. On the other hand, open forest (6.96%), bare areas (0.37%), settlements (1.99%) and agricultural areas (0.21%) increased. For the entire 30-year study period, it is clear that the cork oak forest of Hafir-Zariffet has undergone changes in land cover as supported by the satellite images of 1989 and 2019. The information garnered from this study can serve as a guide for further studies on the drivers of the forest cover change for sustainable forest management interventions.