干旱区生态环境知识资源中心

According to analyze environmental proxies of Qinghai Lake in southwest China, e.g., the grain-size, low frequency magnetic susceptibility (x(lf)), CaCO3 and Total Organic Carbon (TOC), with the AMS C-14 datings and Principal Component Analysis (PCA), the evolution processes of climate environment was reconstructed since 15.0 cal. ka BP. The results show that during 12.7 to 9.6 cal. ka BP, the southwest monsoon was stronger. During 9.6 to 5.0 cal. ka BP, the lake water level was continued to rise, the southwest monsoon was further enhanced. During 5.0 to 0.26 cal. ka BP, the climate was arid gradually. The intensifying human activity and land-use in the lake catchment since 0.26 cal. ka BP were associated with the ancient culture within Qinghai's catchment.