Modélisation de la distribution potentielle de Cedrus atlantica Manetti au Maroc et impacts du changement climatique

Climate change is a major challenge for public policies and the management of natural areas. Understanding its impacts on forest ecosystems is essential to undertake any policy-making for their conservation and preservation of their ecosystem services. This study focused on modelling the potential distribution of Cedrus atlantica Manetti, by identifying the environmental variables governing its distribution and defining the geographical extent of areas favourable to its presence in past, present and future climatic conditions. The study was based on the Maximum Entropy Principle. Mapping of the potential areas of distribution showed the sensitivity of this cedar species to past climate changes and suggests that bioclimatically suitable zones for the development of this species under current climatic conditions cover a large area (four times the current area of occurrence of the species). However, the potential future distribution of the species seems to be dependent on certain specific sites and is liable to be negatively affected by future climatic conditions. Our results show the scale of the projected shrinking of areas suitable for this cedar species in the future, which could have a considerable impact on the functions and services provided by this ecosystem and worsen the risks of local extinction. They also make up a useful decision-support tool for the management of this valuable forest ecosystem to ensure its conservation and avoid the risk of extinction of this locus of biodiversity in Morocco.