Abstract: To explore the potential suitable distribution area of Xanthopappus subacaulis and to clarify the suitable environmental factors, we constructed the relationship model between the distribution of X. subacaulis and environmental factors based on the MaxEnt model and ArcGIS software. We simulated and verified the potential distribution of X. subacaulis in China for different periods of the Last Interglacial (LIG), Last Glacial Maximum (LGM), Mid-Holocene (MH), the current climate conditions, and different future Shared Socioeconomic Pathway (SSP) scenarios, aiming to provide a scientific basis for the protection and rational development and utilization of X. subacaulis. The results showed that: (1) altitude and mean temperature of the warmest quarter were the two most important environmental factors determining X. subacaulis distribution. The total suitable distribution area of X. subacaulis was mainly distributed in eastern Qinghai, southwest Gansu, north and west Sichuan, and east Xizang. (2) Under the climatic context of the LIG, the distribution of X. subacaulis was large-scale and continuous in the northwest of China. However, the whole distribution area mainly decreased towards the vicinity of Qinghai Lake under the climatic background of the LGM. Under the climatic context of the MH, the suitable distribution areas of X. subacaulis were consistent with those of the LGM, except that the highly suitable areas had significantly decreased compared to that of the LGM. (3) Under different CO₂ emission scenarios, the potential suitable habitats of X. subacaulis in 2050 and 2070 show significant differences in distribution patterns. However, the core distribution areas remain relatively stable across these two periods. The entire distribution area of X. subacaulis shows a trend of expansion towards the northeast of Haibei Tibetan Autonomous Prefecture in Qinghai Province. The Qinghai Lake area is projected to be the core expansion zone. However, intensive human activities and insufficient protection coverage in these regions would pose ecological conservation challenges. It is recommended to prioritizing the establishment of new protected areas in expansion hotspots and developing germplasm resource banks for X. subacaulis to reconcile resource utilization and ecological conservation.

Key words: Xanthopappus subacaulis, MaxEnt, ArcGIS, potential distribution area, climate factor