Reconstruction of the Hydrological Cycle in the Nam Co Area Utilizing Sediment Records and Cllimate Models

以西藏中部纳木错地区为例，对该地区的水文循环进行了时空分析，以定量重建过去亚洲季风变化及其对湖泊沉积动力学的影响。已经进行的海底剖面和试验性取芯提供了对湖泊沉积历史的第一次深入了解。此外，地震和沉积物地层学（沉积岩石学、无机/有机化学）可用于确定沉积状况的变化。此外，还进行了实验和建模工作，以重建湖泊的同位素含量。因此，在一个自下而上的多代理方法，包括特定的陆地和水生生物标志物的同位素比值的湖水和降水的同位素含量重建直接和独立于环境条件。一个补充自上而下的方法，侧重于区域古气候模拟重建湖水的同位素含量的初始化。所有这些方法的紧密结合允许定量的理解和重建的降水和蒸发通量的变化，以及它们与沉积系统的纳木错集水区的相互作用。一个综合与支持代理数据的合作伙伴，这一联合研究计划以及C测年将有助于解释的结果与当地和全球方面的晚第四纪气候变化。

The hydrological cycle in the Nam Co area, Central Tibet is spatio-temporally assessed in order to quantitatively reconstruct the past Asian Monsoon variability and its influence on lake sediment dynamics. The already conducted sub bottom profiling and pilot coring provide a first insight into the sedimentary history of the lake. Furthermore, seismic and sediment stratigraphy (sedimentary petrology, inorganic/organic chemistry) allows identifying changes in the sedimentary regime. Additionally experimental and modelling work is carried out to reconstruct the isotopic content of the lake. Therefore, in a bottom-up multi proxy approach including isotope ratios of specific terrestrial and aquatic biomarkers the isotopic content of the lake water and precipitation is reconstructed directly and independently from environmental conditions. A complementing top-down approach focussing on regional palaeoclimate simulations to reconstruct the isotopic content of the lake water is initialised. Tight integration of all these methods allows a quantitative understanding and reconstruction of precipitation and evaporation flux changes as well as their interaction with the sedimentary system of the Nam Co catchment. A synthesis with supporting proxy data from the partners of this joint research initiative as well as C dating will serve to interpret the results with regard to local and global aspects of Late Quaternary climate change.