博斯腾湖-罗布泊流域生物分子标志物记录的全新世气候水文变化

全球变暖背景下水资源分布不均正严重威胁亚洲中部干旱区生态环境安全，并制约了区域可持续发展。研究过去气候变化对水文系统的调控作用可以为科学评估未来水资源空间分布提供历史参照。但目前对亚洲中部干旱区全新世气候-水文变化特征及其地带性差异的认识并不一致，阻碍了深入理解气候变化对水资源时空分配的影响。本项目拟选择塔里木盆地东部同处于孔雀河流域不同地貌类型的博斯腾湖和罗布泊为研究对象，在开展GDGTs化合物现代过程研究的基础上，建立适用于不同湖泊的温度转换方程；分别利用叶蜡氢同位素和GDGTs重建两个地区全新世大气降水与古温度变化序列；综合对比周缘典型山地气候记录，探讨局地水热配置差异对盆-山耦合地区全新世千年尺度和关键时期气候-水文变化的影响。本研究将为理解亚洲中部干旱区不同地貌单元气候-水文变化特征异同及其驱动机制提供关键证据，同时也为研究过去东西方交流与丝路文明演化提供气候变化背景。

The uneven distribution of water resources seriously threatens the ecological and environmental security in the arid central Asia (ACA), as well as the regional sustainable development of human society under the background of global warming. Studying the effect of past climate change on the regulation of hydrological systems can provide historical reference for scientific assessment of water resources on space in the future. However, the Holocene evolution of hydroclimate changes in ACA is increasing debated, and the knowledge about the zonal difference in this region is still controversy, hindering the comprehensive understanding of the impact of climate changes on the spatial-temporal distribution pattern of water resources. Bosten Lake and Lop Nur in the eastern Tarim basin belong to different geomorphic units within the Konqi River catchment, representing the typical lakes of intermountain basin and inland basin. Lake sediments from Bosten and Lop Nur provide us to investigate the Holocene hydroclimate variations and the mechanisms. This proposal intends to establish the GDGTs-temperature transfer functions according to modern process, to reconstruct past precipitation and temperature variability for the two lakes by using leaf wax hydrogen isotope ratios and GDGTs, respectively. A comparison study combined with the published records from the surrounding mountain areas, to demonstrate the hydroclimate changes during Holocene at different geomorphic units and related influence factors on millennium timescale, as well as the HTM, MWP and LIA periods. This study provides a comprehensive interpretation of the heterogeneity of hydroclimate variations at different geomorphic units, together with the associated mechanisms for understanding spatial distribution of water resources in ACA. In addition, it helps reveal the climatic background for the cultural exchange and development of ancient Silk Road civilization.