Climatic and Environmental Changes in More Than the Past 1800 Years as Recorded by Isotopic Carbon and Nitrogen in Organic Matter of Sediments from Western Foye Chi (Buddha Pond) on Taibai Mountain

GAO Yishen, WANG Hongya†, CHENG Ying, LIU Hongyan, ZHU Chenyi

Key Laboratory for Earth Surface Processes (MOE), School of Urban and Environmental Sciences, Peking University, Beijing 100871; † Corresponding author, E-mail: why@urban.pku.edu.cn

Abstract A 50-cm core (hereafter referred to as “XFYC12-2”) was retrieved from western Foye Chi (Buddha Pond), a glacier-scour lake on southern slope of Taibai Mountain that is the main massif and peak of Qinling Mountain Range. Accelerator mass spectrometry (AMS) 14C dating and analyses of isotopic carbon and nitrogen of organic matter were performed on samples from XFYC12-2. Climatic and environmental changes occurring around this alpine during over the past ~1800 years were therefore reconstructed. Climatic and environmental conditions were still fairly cool and arid during 18111380 (or 1440) ABP. In 1380 (or 1440)840 ABP, the climate and environment were warm and humid. This episode is probably corresponding to Medieval Warm Period (MWP). 840‒460 Climatic and environmental conditions deteriorated subsequently and were thus cold and dry over the period of

(or 520) ABP. This phase may correspond to Little Ice Age (LIA). Climatic and environmental conditions have turned to be warm and wet again during 460 (or 520)100 ABP. The aforementioned process of climatic and environmental changes appears quite similar to what was reconstructed around another two lakes at the high altitudes of Taibai Mountain, what was generalized for eastern China and what was identified at another four study areas in eastern China. Key words Taibai Mountain; western Foye Chi (Buddha Pond); carbon and nitrogen isotopes of organic matter; climatic and environmental changes