An ice-core record of vegetation and climate changes in the central Tibetan Plateau during the last 550 years  

作　　者：YANG Bao TANG LingYu LI ChunHai SHAO YaJun TAO ShiCheng YANG LunQing 

机构地区：[1]Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China [2]MOE Key Laboratory of West China's Environmental System College of Earth and Environment Sciences, Lanzhou University, Lanzhou 730000, China [3]Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China [4]Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China

出　　处：《Chinese Science Bulletin》2010年第12期1169-1177,共9页

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 40871091 and 40671196);Hundred Talent Project of the CAS (Grant No. 29082672);CAREERI of CAS (Grant No. 51)

摘　　要：We present a 550-year ice-core pollen record with a 5-year resolution from the Puruogangri ice field in the central Tibetan Plateau.Analysis of the relationship between pollen record and instrumental observations suggests that the sum of the steppe and meadow pollen taxa is a good indicator of summer (June-August) temperature,whereas the ratios of Cyperaceae/(Gramineae+Artemisia) [Cy/(G+A)] as well as M/S (meadow to steppe percentages) are indicative of humidity changes in this region.Together with δ18O and glacial accumulation records,the response of vegetation to climate change over the past 500 years was revealed.Desert vegetation dominated during 1450-1640 AD,a time period characterized by cold-wet climate,while steppe vegetation expanded during 1640-1915 when warm-dry climate prevailed.Afterwards,during a cold and humid period,desert vegetation expanded again.Since 1980-2002,due to the increase of summer temperatures,steppe and meadow vegetation predominates,while areas with desert vegetation are reduced.This proxy series is the first high-resolution ice-core pollen record spanning the last 550 years for the central Tibetan Plateau.We present a 550-year ice-core pollen record with a 5-year resolution from the Puruogangri ice field in the central Tibetan Plateau. Analysis of the relationship between pollen record and instrumental observations suggests that the sum of the steppe and meadow pollen taxa is a good indicator of summer （June-August） temperature, whereas the ratios of Cyperaceae/（Grarmineae＋Artemisia） [Cy/（G＋A）] as well as M/S （meadow to steppe percentages） are indicative of humidity changes in this region. Together with δ18 O and glacial accumulation records, the response of vegetation to climate change over the past 500 years was revealed. Desert vegetation dominated during 1450-1640 AD, a time period characterized by cold-wet climate, while steppe vegetation expanded during 1640-1915 when warm-dry climate prevailed. Afterwards, during a cold and humid period, desert vegetation expanded again. Since 1980-2002, due to the increase of summer temperatures, steppe and meadow vegetation predominates, while areas with desert vegetation are reduced. This proxy series is the first high-resolution ice-core pollen record spanning the last 550 years for the central Tibetan Plateau.

关 键 词：沙漠植被 青藏高原 气候变化 中央 冰核 草甸草原 普若岗日冰原 夏季气温 

分 类 号：P467[天文地球—大气科学及气象学] S423.1[农业科学—植物保护]