Predicting Potential Distribution of the Acanthopanax Sessiliflorus in China Under Future Climate Scenarios Based the...

Acanthopanax sessiliflorus (Rupr. Maxim.) Seem. is an ecologically and medicinally important shrub in East Asian temperate forests, yet its habitat dynamics under climate change remain poorly quantified. In this study, an optimized Maximum Entropy (MaxEnt) model was developed using climatic, soil, and topographic variables to project habitat suitability under four future climate scenarios (SSP126, SSP245, SSP370, SSP585) from the 2040s to the 2100s. Model performance was high, with a mean training AUC of 0.9735 and a testing AUC of 0.9660. The current suitable habitat covers 89.97 × 10⁴ km², with a centroid at 118.800934° E, 39.230015° N. Highly suitable areas (3.05 × 10⁴ km²) are concentrated in Hebei, Beijing, Liaoning, and the Changbai Mountains. Temperature seasonality (Bio4, 41.5%) was identified as a dominant factor, while maximum temperature of the warmest month (Bio5) contributed important independent information. Future projections show strong scenario dependence. Based on projections for the 2100 time point, highly suitable habitat is predicted to decline across all scenarios: decreasing by 38.43% under SSP126, 62.15% under SSP245, 70.20% under SSP370, and 79.27% under SSP585. Total suitable habitat is projected to increase by 29.74% under SSP126, due to the expansion of marginally suitable areas. In contrast, SSP245, SSP370, and SSP585 show initial expansion followed by long-term contraction, with a 21.74% net loss under SSP585 by 2100. Habitat centroids are projected to shift northwestward, indicating spatial redistribution. Overall, intensive future emission scenarios will degrade core habitats and reorganize these temperate ecosystems. By identifying climatic sensitivities, this study provides a scientific foundation for optimizing cultivation, managing wild resources, and developing climate-adaptive conservation strategies to ensure the sustainable utilization of this medicinal shrub.