When Climate Changes, How Do Valuable Tree Species Distribution Change in the Sudanian Domain of Senegal?

Climate change is a growing concern, and its effects on biodiversity may depend largely on its consequences on the distribution of species that play a key role in communities. This study aims to determine whether forests in the Sudanian zone of Senegal will maintain the environmental conditions required for fifteen valuable species to persist under a range of climate change scenarios. We used forest inventory data from 2,398 plots and five bioclimatic variables as predictors. The distribution of the species was evaluated under three SSP scenarios (SSP2-4.5, SSP3-7.0 and SSP5-8.5) for the 2100 horizon by developing models for each species under each scenario using multiple logistic regression with a binomial distribution of the response. The findings indicate that the mean annual temperature is expected to increase in the region for all SSPs considered, while for precipitation metrics, some variability was observed depending on the scenarios. As demonstrated by our results, species distribution changes exhibited differences. Our models indicate a negative impact of climate for nine species, specifically Acacia macrostachya, Bombax costatum, Cordyla pinnata, Combretum micranthum, Detarium microcarpum, Prosopis africana, Pterocarpus erinaceus, Sterculia setigera and Terminalia avicennioides, under scenarios SSP2-4.5 and SSP3-7.0. These species would face significant declines under the most extreme scenario, scenario SSP5-8.5. The following species are predicted to decline significantly under the SSP2-4.5 and SSP3-7.0 scenarios: Pterocarpus erinaceus, Sterculia setigera, Terminalia avicennioides, and to be completely lost under the SSP5-8.5. Three species would maintain their distribution area under all scenarios SSP5-8.5. The results also indicate that species tend to move in a general west-southwest trajectory. Overall, the majority of high-value species are vulnerable to future climate, with a high risk of local extinction in the sudanian zone. This finding indicates the necessity for a reorientation of forest management strategies towards the implementation of adaptive management strategies to ensure the long-term resilience of forests. Urgent actions such as the development of specific management plans and monitoring schemes for vulnerable tree species, with the objective of minimizing their harvesting and promoting their regeneration, are required.