地质学报2017，Vol.91Issue(1)：266-286,21.
青藏高原东北缘共和—贵德盆地全新世气候变化
Loess Records of the Holocene Climate Change of Gonghe and Guide Basins in the Northeastern Boundary of the Tibet Plateau
摘要
Abstract
The northeastern margin of the Tibetan Plateau located at the northern boundary of modern Asian monsoon transition and transition zone of arid and semi-arid area in China,due to sediment sensitive to climate change,is an ideal place to study the plateau Holocene winter monsoon system response to global change.According to the dynamic principle of dusttransportation,by using characteristics of the combination of temperature and humidity,wind strength and dust source distance,the Holocene climatic fluctuations,regional environmental change and the relationship between winter and summer monsoons are analyzed in the study.The following conclusions are obtained:①The estimation methods of proxy indices of wind strength of atmospheric dust,dust transport distance,air-turbulence intensity,spring near-surface air temperature and humidity are established.②Southwest monsoon dominated Gonghe and Guide Basins during the Holocene period.Plateau winter monsoon is a key winter monsoon in the region and there has a different evolutionary pattern of near-surface wind field in the above region due to the effect of mountains.③Climatic change of the Holocene can be divided into four stages in Gonghe and Guide Basins,the first stage is about 6.5 ～ 4.2kaBP that is the Holocene Optimum,characterized by significantly increased humidity and slightly elevated temperature.The second stage is about 2.6～4.2kaBP and characterized by cold and dry climate,dust source expansion.Both winter and summer monsoon weakened in the stage.This cold and dry event was also appeared in the northwest dust source area of plateau monsoon system and dust source areas of Asian monsoon system.The third stage is about 1.2～2.6kaBP.In the period,dust source shrinked,eco-environment was improved and summer monsoon slightly enhanced.The fourth stage is after 1.2kaBP when humidity increased and climate tended to be cold and wet.关键词
青藏高原/全新世/共和盆地/贵德盆地/气候变化Key words
Tibet Plateau/Holocene Climate change/Gonghe and Guide Basin/loess and paleosol/dynamic mechanism of dust settlement引用本文复制引用
秦小光,殷志强,汪美华,赵无忌,穆燕,张磊..青藏高原东北缘共和—贵德盆地全新世气候变化[J].地质学报,2017,91(1):266-286,21.基金项目
本文为国家自然科学基金项目(No.41372333,41372187,41172158,40472094和40024202)、科技部973项目(2010CB950200)和中国科学院知识创新项目(KZCX2-YW-Q1-03)共同资助. （No.41372333,41372187,41172158,40472094和40024202）
