Predicting the Implications of Climatic Alterations on the Distribution of Endangered Species: A Case Study of Saxifragaceae on the Qinghai-Xizang Plateau.

Understanding the potential impacts of climate change on species distribution is crucial for the conservation of threatened taxa. The Saxifragaceae family, known for its susceptibility to habitat disturbance, exhibits a diverse distribution across multiple regions. While a significant proportion of this family is found on the Qinghai-Xizang Plateau (QXP), nearly half of the Saxifraga species are native to Europe, with other genera, such as , showing centers of diversity in North America and Japan. This study applies the Maximum Entropy (MaxEnt) model in combination with Shared Socioeconomic Pathways (SSPs) to assess the potential influence of climate change on the distribution and species richness of four endangered Saxifragaceae species ( L., Engl., Engl. ex-Maxim., Engl.) on the QXP, spanning from the Last Glacial Maximum to 2080. Our findings reveal that key environmental factors, including elevation, slope, mean annual temperature, isothermality, precipitation seasonality, and precipitation during the wettest quarter, significantly influence species distribution patterns. Historical climate models suggest that approximately 30% of the QXP provided highly suitable habitat for Saxifragaceae species, a proportion that has increased to over 30% in current projections, with this trend expected to persist across the next three time intervals. Optimal habitats were identified in the southeastern QXP, western Sichuan, and northern Yunnan. Projections indicate that these taxa will likely shift southward in response to ongoing climate changes. These results highlight the need for targeted conservation strategies, emphasizing the establishment of protected areas in southeastern QXP to preserve these vulnerable species of Saxifragaceae.