Impact of current and future climate change on the potential habitat suitability of Quercus coccifera L. in the Southern Mediterranean: Comparative study

Predicting spatial changes in plant species distribution under climate change remains a critical challenge in biogeography and ecology. The genus Quercus L. is notable for its high ecological diversity and substantial economic value, particularly for hardwood production. However, the natural distribution of oak species is severely threatened by anthropogenic activities, including overgrazing, urbanization, agriculture, and deforestation, which have led to widespread forest fragmentation. In this study, we employed the HadGEM3-GC31-LL global climate model and two Shared Socio-economic Pathway (SSP) scenarios to assess the current and future potential distribution of the Mediterranean species Quercus coccifera L. and its suitable habitats in North Africa. Predictive modeling was conducted using an ensemble approach integrating three Species Distribution Models (SDMs), Boosted Regression Trees (BRT), Generalized Linear Models (GLM), and Random Forests (RF), implemented in R version 1.1-8. Our findings indicate that under all evaluated climate scenarios for the 2050s and 2070s, habitat suitability and distribution range of Q. coccifera in North Africa will decline. Under both SSP scenarios, only marginal expansions (0.02%–0.07%) are projected in the northwestern sector of the study area. Overall, population declines are expected to be more pronounced in North Africa and the Eastern Mediterranean than in the Western Mediterranean basin. Considering the optimal growth conditions for Q. coccifera within the Mediterranean basin, targeted conservation efforts could help sustain this ecologically and economically valuable species. Beyond climate change, genetic variation among populations and disease pressures may further modulate its growth and spatial distribution across Mediterranean countries. These results underscore the urgent need for conservation strategies aimed at mitigating the decline of Q. coccifera populations in North African and Eastern Mediterranean regions.