Periglacial Lake Environments in Eastern Siberia
作者单位：Alfred Wegener Institute for Polar and Marine ResearchResearch Station Potsdam Department of EcologyYakutsk State University Institute of LimnologyRussian Academy of Sciences
会议名称：《Asian Conference on Permafrost》
会议日期：2006年
学科分类：07[理学] 0705[理学-地理学] 070501[理学-自然地理学]
关 键 词：East Siberia holocene climate limnogeology thermokarst alass lake status
摘 要：Research work during the last decades highlighted the role of the northern high-latitude regions for global climate *** climatic influence arising from the vast periglacial regions of eastern Eurasia is poorly *** regions were only affected by regional mountain glaciations,are covered by Taiga and Tundra vegetation and are characterized by deep-reaching frozen *** particular,Yakutia in the northeastern part of Eurasia represents one of Earth’s most extreme climate regions with semiarid continental climate and coldest winter temperatures on the northern *** landscape of Yakutia is occupied by widespread lake *** sediment records of these lakes provide the basis for palaeolimnological reconstructions of former environmental and climate conditions of the periglacial realm in eastern *** using sedimentological,geochemical,and micropalaeontological proxy records,including the application of ecological transfer functions,an interdisciplinary approach is followed to characterize the dynamics of lacustrine systems related to Holocene climate *** lakes of tectonic-glacial origin are located at the Verkhoyansk Mountain *** mostly oligotrophic lakes are dominated by siliciclastic muds with low abundances of organic *** in grain-size characteristics indicate variations in fluvial sediment runoff,possibly related to spring snow *** majority of Yakutian lakes are eutrophic and occur in shallow closed to semiclosed thermokarst depressions and in deep alass *** of the semiarid climate setting,the lakes respond very sensitively to perturbations in the hydrological balance,driven by summer precipitation and *** longer time scale,pollen and chironomid records in the lacustrine sediments document an early Holocene climate optimum between 8.0 and 4.5 ka BP with generally warm and wet summer *** the same time,a marked variability in the proportions of pe