The potential impact of glacier volume changes on biome dynamics in the southeastern margin of the Tibetan Plateau since the last deglaciation

The changing climate has clearly influenced the vegetation in southwestern China since the last deglaciation. However, the varying vegetation succession patterns and responses to large-scale climate events during this period have sparked debate. Here, we present a well-dated, continuous pollen record from Erhai (EH) lake on the southeastern margin of the Tibetan Plateau, to discuss biome variation and its relative forcings over the past 17.2 kyr. Our results indicate that evergreen sclerophyll Quercus forests (ESQF) were predominant surrounding the EH site during the early deglaciation (17.2–12.5 cal ka BP), and that the ESQF transitioned to deciduous broadleaved forest (DBLF) and Tsuga forest (TSUF) around 12.5 cal ka BP during the YD event. During the early to mid-Holocene, the mountain vegetation belts surrounding EH lake were likely similar to the original vegetation present in modern times. Since approximately 2 cal ka BP, a significant increase in anthropochorous taxa proportions has been recorded, largely attributed to early human activities and fire disturbances. Although the warming and wetting trends did not exceed the optimal growth range for Quercus (ES) during the last deglaciation, allowing ESQF to continue growing extensively on sunny mountain slopes, our findings clearly disclosed the regional disparities in vegetation responses to climate change across SW China. Moreover, millennial-scale glacier fluctuations on the southeastern margin of the Tibetan Plateau, influenced by monsoon precipitation, likely played a role in driving vegetation succession in the mountains surrounding the EH lake and other areas of the Hengduan region since the deglaciation.