中德联合冬给措纳湖地区寒区环境变迁研究进展

Sino-Germany Joint Investigated Environmental Changes in Donggi Conag Lake Area on Qinghai-Tibet Plateau

青藏高原腹地的内陆湖及其湖相沉积物能够较真实地反映气候变化特征，在高原环境变迁研究中备受中外科学家的关注,2006年8月15日～9月10日，中德联合考察小组对青藏高原东北部的冬给措纳湖一带进行了第四纪冻土、地貌和地质学考察，并对湖岸阶地做了初步的数字高程分析,调查了冬给措纳湖底地形、地貌，采集了湖相沉积物样本,在湖的东岸和西岸发现多年冻土，湖泊西北山谷观察到古冰川活动遗迹,初步推测该湖是由断陷沉降形成,为进一步分析湖区气候和环境变迁，联合小组拟定2007年3月份钻取湖芯．

Inland lakes and lacustrine sediments on the Qinghai-Tibet Plateau can provide reliable proxy records for paleoenvironmental reconstruction and are therefore studied by increasingly more researchers. A Sino-Germany joint team investigated topography, geomorphology and sedimentology in the Donggi Conag Lake （220 km^2; 98°21＇ -98°43＇E, 35°13＇-35°23＇N; 4081m） area on northeastern Qinghai-Tibet Plateau from 15 August to 10 September 2006. The lake terraces were analyzed by digital elevation model （DEM）. The lake bottom profiles were preliminarily studied using shallow seismic, sonar and GPS instruments and several core samples of lake sediments up to 1.9 ;n in length were taken for further analyses. Permafrost was found along the eastern and western banks of this lake. Sediment analysis and geomorphology indicate the existence of Quaternary glaciations in a valley to the northeast of the Lake. It is preliminarily concluded that the Donggi Conag Lake was formed by fault settlement. To further understand climatic and environmental changes in this area, the Sino-German joint research team is planning to core lake sediments in March 2007.