Assessing Niche Dynamics and Population Connectivity in an Endangered Tree Species, Emmenopterys henryi: Implications for Conservation and Management

Understanding the niche dynamic among distinct populations and delineating the dispersal corridors that exist between them under current climates is critical for elucidating the contemporary forces driving genetic divergence, facilitating population connectivity, and informing targeted conservation efforts, particularly for species exhibiting pronounced intraspecific lineages. In this study, we focus on evaluating the range and niche dynamics of the intraspecific lineages of Emmenopterys henryi and exploring potential patterns of population connectivity both within and across these lineages. Our findings unveiled a significant niche divergence between the two intraspecific lineages, characterized by limited overlap in climatic conditions and suitable ranges. Furthermore, our analysis of population connectivity revealed the presence of dispersal routes with varying degrees of connectivity within each lineage, while low connectivity was observed between the two lineages. Our results highlight the critical role of fine-scale ecological niche models (ENMs) and genetic connectivity analyses in elucidating the complexities of niche evolution and genetic connectivity, particularly for species with discrete intraspecific lineages. In addition, given the fact that rapid genetic erosion of species inhabiting the regions we focus on in this study is often associated with habitat loss and fragmentation, our findings will also offer valuable insights for designing targeted conservation strategies aimed at restoring connectivity and increasing local population sizes for this endangered species.