Predicting the potential distribution and climatic response of the endangered medicinal and edible species, Anoectochilus roxburghii, using an optimized MaxEnt model

Abstract

Assessing how the habitat suitability and distribution of endangered species may alter under future climate scenarios is essential for robust conservation strategies. Anoectochilus roxburghii, an endangered and medicinally important orchid, faces significant threats from climate change due to its specific habitat requirements. This study predicts its potential distribution dynamics from the Last Glacial Maximum to the 2070s to inform conservation. We employed an optimized Maximum Entropy (MaxEnt) model, using species occurrence records and environmental variables to project its suitable habitats under past, current, and future (SSP126 and SSP585 scenarios) climates. The model performed excellently (AUC = 0.965), identifying the Mean Temperature of the Coldest Quarter (bio11) and Annual Precipitation (bio12) as the primary limiting factors. Historical simulations revealed habitat contraction into southern refugia during glacial periods and expansion during warmer interglacials. Future projections indicate a significant northward expansion of suitable habitats, a shift that is substantially more rapid and extensive under the high-emissions SSP585 scenario. These findings provide a scientific basis for proactive conservation. We recommend strengthening in situ protection in stable southern refugia, prioritizing germplasm collection from contracting populations, and guiding artificial cultivation into newly suitable northern regions to mitigate climate change impacts and reduce pressure on wild populations.