Lake system response of Nam Co area, central Tibet, to Late Quaternary Monsoon dynamics: Microfossils as recorders of environmental change

西藏中部纳木错地区湖泊系统对晚第四纪季风动力学的响应：微化石作为环境变化的记录者

• 批准号: 14456666
• 负责人: Professorin Dr. Antje Schwalb
• 金额: --
• 依托单位: Institut für Geosysteme und Bioindikation
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/14456666?language=en
• 关键词: Lake; system; response; Nam; Co

In August/September 2005, during the pilot phase of this project, we have carried out a limnological survey that included the collection of water column samples from Nam Co, water samples from tributaries, surface sediments and short cores. Long cores (max. 4.7 m) and outcrop sediments were collected in cooperation with partners. Preliminary analyses show that there are abundant microfossils, especially ostracodes that document the suitability of Nam Co sediments for an evaluation of the response of Nam Co and its catchment area to environmental dynamics and climate change. This proposal seeks funding for a detailed microfossil analysis of sediment cores and outcrop sediments in order to characterize the lake system response to climate change during (1) recent decades, and (2) during the Holocene, as well as to characterize the (3) dynamics of past lake level high stands. Fossil ostracode species assemblages and the oxygen and carbon isotopic signatures from their valves will provide information about, for example, the precipitation vs. evaporation ratio, lake level changes and water supply to the lake such as meltwater runoff that is controlled by monsoon dynamics and temperature. We also plan to carry out a second field work phase at Nam Co followed by an exploratory survey in S. Tibet together with cooperation partners.

2005年8月/9月，在该项目的试点阶段，我们进行了湖泊学调查，包括采集纳木错水柱样本、支流水样、表层沉积物和短岩芯。与合作伙伴合作收集长岩心（最大 4.7 m）和露头沉积物。初步分析表明，存在丰富的微化石，特别是介形类化石，证明纳木错沉积物适合评估纳木错及其流域对环境动态和气候变化的响应。该提案寻求资助对沉积物岩心和露头沉积物进行详细的微化石分析，以便表征（1）近几十年和（2）全新世期间湖泊系统对气候变化的响应，以及表征（3）过去湖水位高位的动态。化石介形类物种组合及其阀门的氧和碳同位素特征将提供有关降水与蒸发比、湖泊水位变化和湖泊供水（例如受季风动态和温度控制的融水径流）等信息。我们还计划在纳木错开展第二阶段实地工作，随后与合作伙伴一起在西藏南部进行探索性调查。