Late Glacial to Middle Holocene climate and environmental changes as recorded in Lake Dood sediments, Darhad Basin, northern Mongolia

摘要

The paper presents new data on climatic, lake level and environmental changes in the Darhad Basin, northern Mongolia, during the Late Glacial and Early to Middle Holocene. Two cores, DN1 and DN2, from Lake Dood were investigated using the following proxies: grain size, total carbon (TC), total inorganic carbon (TIC), total organic carbon (TOC), total nitrogen (TN), total sulfur (TS), δ~(13)C, δ~(18)O and diatom. Our reconstructions indicate that dramatic climatic and environmental changes occurred several times since ca 14 ka cal BP. A cold and dry climate of the Late Glacial changed to a relatively cold and wet climate starting around 9.5 ka cal BP in response to an Early Holocene humidization. A generally warm and humid climate prevailed in the region at ca. 7.8-5.8 ka cal BP. Later on after 5.8 ka cal BP the climate became cooler and drier. The Darhad paleolake, the predecessor of Lake Dood, disappeared during the Late Glacial to Early Holocene times and started to reappear since ca. 9.5 ka cal BP. Lake Dood fluctuated considerably in response to changes in precipitation or/and in ground ice melting between 9.5 and 5.8 ka cal BP and started to decrease at 5.8 ka cal BP.