FIGURE 3 The potential distribution ranges for four Lamiaceae species from the past to the future in the Third Pole. The color gradient from green to red represents low to high suitability. LIG, Last Interglacial (116-129 ka); LGM, Last Glacial Maximum (18-26.5 ka); SSP126 and SSP585 represent two Shared Socio-economic Pathways (SSPs) in the year 2090.
Simulations indicate that the species’ potential distribution areas shifted upwards and northwards, expanding significantly from LIG to LGM. During the LGM, species held continuous potential distribution areas along the HHM corridor. Following the post–LGM climate warming, the suitable habitats for the species migrated towards higher altitudes (Table 1). Consequently, their low–altitude distributions disappeared, resulting in isolated distributions in the Himalayas and Hengduan Mountains ( Figure 3 and Figure 4). Meanwhile, species have acquired new distribution areas and successfully established populations on the Qinghai Tibet Plateau. From LGM to current, the diffusion forElsholtzia eriostachya and Marmoritis complanata has been accompanied by significant distribution area migration, with over 60% loss and new acquisition. The distribution changes of Eriophyton wallichii and Phlomoides rotata are less pronounced, but they exhibit a contraction trend, at least 27% lost.