An in-depth understanding of the relationship between climate change and anthropogenic activities under extreme climate conditions could provide a scientific basis and historical reference for properly coping with future climate change and ensuring the sustainable development of ecology, environment, economy and society. Here, fecal stanols in the sediment core of Xiada Co on the western Tibetan Plateau was used to reconstruct changes in local human populations from 4700 cal years BP to the present. brGDGT and X-ray fluorescence (XRF) data in the same sediment core were used to reconstruct regional climate history. Some archaeological and documentary evidence from the Tibetan Plateau were also compiled. Our analysis indicates that the pattern of a warm and arid climate possibly facilitates the growth of human  population in the catchment area of the Xiada Co. During the past 2000 years, social factors had more and more influence on human activities. And the smallest human  population occurred after ~300 cal yr BP due to the integration influence of a cold and arid climate, wars, and conflicts. 

Tibetan Plateau,biomarkers,Faecal stanols,middle Holocene,human population,climate change