Vegetation and climate changes during the last 8660 cal.a BP in central Mongolia,based on a high-resolution pollen record from Lake Ugii Nuur  

作　　者：WANG Wei MA YuZhen FENG ZhaoDong MENG HongWei SANG YanLi ZHAI XinWei 

机构地区：[1]Key Laboratory of Western China's Environmental Systems, Ministry of Education of China & College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China [2]Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China & State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China [3]Department of Geology, Baylor University, Waco, Texas 76798, USA

出　　处：《Chinese Science Bulletin》2009年第9期1579-1589,共11页

基　　金：Supported by National Natural Science Foundation of China (Grant Nos. 40331012, 40671190, 40421101);U.S. National Science Foundation (Grant Nos. NSF-ESH-04-02509, NSF-BCS-06-23478, NSF-BCS00-78557)

摘　　要：Based on modern pollen studies and reliable chronology of nine AMS 14C dates, a detailed history of vegetation and climate changes during the past 8660 cal. a BP was reconstructed by a high-resolution pollen record from Ugii Nuur in central Mongolia. Poaceae-steppe dominated the study area and the climate was mild and semi-humid before 7800 cal. a BP with a noticeable cool and humid interval at 8350―8250 cal. a BP. Xerophytic plant increased and the climate became warm and dry gradually since 7800 cal. a BP. From 6860 to 3170 cal. a BP, semi-desert steppe expanded, suggesting a prolonged warm and dry climate. Between 3170 and 2340 cal. a BP, regional forest steppe expanded whereas semi-desert steppe retreated, indicating the climate became cool and wet gradually and the humidity reached the maximum at the end of this stage. From 2340 to 1600 cal. a BP, a general cool and wet climate prevailed. And the climatic instability increased after 1600 cal. a BP. Review of regional pub-lished palaeoclimatic records implies that the mid-Holocene dry climate might have prevailed in vast areas from central Mongolia to arid areas of northwest China. Pollen-based climate reconstruction for UG04 core was well correlated with the result of climate model on Central Asia by Bush. In addition, several abrupt climatic events (cool and wet) were found and some could be broadly compared with the cool events in Atlantic.Based on modern pollen studies and reliable chronology of nine AMS ^14C dates, a detailed history of vegetation and climate changes during the past 8660 cal. a BP was reconstructed by a high-resolution pollen record from Ugii Nuur in central Mongolia. Poaceae-steppe dominated the study area and the climate was mild and semi-humid before 7800 cal. a BP with a noticeable cool and humid interval at 8350-8250 cal. a BP. Xerophytic plant increased and the climate became warm and dry gradually since 7800 cal. a BP. From 6860 to 3170 cal. a BP, semi-desert steppe expanded, suggesting a prolonged warm and dry climate. Between 3170 and 2340 cal. a BP, regional forest steppe expanded whereas semi-desert steppe retreated, indicating the climate became cool and wet gradually and the humidity reached the maximum at the end of this stage. From 2340 to 1600 cal. a BP, a general cool and wet climate prevailed. And the climatic instability increased after 1600 cah a BP. Review of regional published palaeoclimatic records implies that the mid-Holocene dry climate might have prevailed in vast areas from central Mongolia to arid areas of northwest China. Pollen-based climate reconstruction for UG04 core was well correlated with the result of climate model on Central Asia by Bush. In addition, several abrupt climatic events （cool and wet） were found and some could be broadly compared with the cool events in Atlantic.

关 键 词：气候变化 花粉记录 UGII BP 蒙古 植被 基础 荒漠草原 

分 类 号：P467[天文地球—大气科学及气象学] P532