Synergizing climate dynamics, species distribution, and structural parameters for sustainable management of Pseudrocedrela kotschyi in Benin (West Africa)

Climate change poses significant threats to biodiversity, profoundly impacting plant species. Pseudocedrela kotschyi, a vital component of tropical ecosystems is experiencing severe population decline due to habitat degradation and regeneration issues. Understanding how climate change exacerbates these problems combined with assessment of its structural parameters is essential for developing conservation strategies and ensuring the survival of this species. Occurrence records and bioclimatic data were utilized for niche modeling. Additionally, forest inventories were conducted across various habitats of the species in Benin, to characterize the structural parameters of its populations. An ecological niche modeling approaches was used to depict niche differentiation among subpopulations of Pseudocedrela kotschyi and assess the climate change impacts on the sepecies in Benin. The Maximum Entropy Algorithm (MaxEnt) was used to simulate the species’ current and future distributions under different shared socio-economic pathway (SSP) climate scenarios. Three distinct populations of the species were identified. The populations exhibited no niche overlap among subpopulations indicating local adaptation. In non-protected areas, P. kotschyi individuals tend to be smaller in size. This trend is particularly pronounced in the Sudano-Guinean zone, where protected habitats benefit from a higher monthly thermal amplitude. In contrast, in the Guineo-Congolian zone, both protected and unprotected habitats are influenced by the minimum temperature of the coldest month and the mean annual temperature, leading to higher densities of regeneration and adults of P. kotschyi. In the Sudanian zone, regardless of the protection status, higher annual rainfall supports larger mean diameters for P. kotschyi and its population. This study underscores the importance of preserving the species' habitats, regulating potentially harmful human activities, and incorporating future climate forecasts into management plans to ensure the sustainable conservation of P. kotschyi.