柴达木盆地上新世晚期以来古气候演变的孢粉环境指标重建  

The Palaeoenvironmental Reconstruction on Pollen proxy in the Qaidam Basin since Late Pliocene

作　　者：孙非非[1] 张菀漪[1] 巩俊成[1] 张成君[1] 

机构地区：[1]兰州大学资源环境学院,兰州730000

出　　处：《地质论评》2010年第5期621-628,共8页Geological Review

基　　金：国家自然科学基金资助项目(编号40773064)的成果

摘　　要：本文根据柴达木盆地尕斯库勒湖、大浪滩、察汗斯拉图、昆特依、马海、一里坪、三湖地区15个钻孔岩芯孢粉种属鉴定统计,对其中的蒿属、藜科孢粉含量和蒿藜比值(A/C)进行分析,通过在干旱区该比值现代生态环境意义的了解,重建了柴达木盆地新近纪晚期以来古气候的演变特征。分析表明,柴达木盆地上新世晚期以来气候一直向干旱方向发展,但干湿波动较大,尤其从中更新世以来更为明显。盆地气候干湿变化的空间规律比较明显,总体上有从东部湿润到西部干旱的特征,这种空间规律在下更新世甚至更早时期就已经形成。盆地气候环境的干冷—暖湿气候演变规律说明盆地主要受冬季风和东南、西南季风,以及青藏高原和盆地周围的高山的影响,盆地各处干湿变化特征差异较大。Writers accounted the pollen species in the 15 cores of Lake Gasikule,Dalangtan,Chahansilatu,Kunteyi,Mahai,Yiliping,and Dabuxun Lake,Senie Lake,Taijinaier Lake （three lakes area） in the Qaidam Basin. Artemisia and Chenopodiaceae pollen content and the ratio （A/C） have been analyzed. And the palaeoclimatic change have been reconstructed in this basin since Late Pliocene based on analysesing the modern ecological environment characteristics about the A/C ratio. It was shown that the palaeoclimate was dry all through the late Pliocene to present but with a great dry—wet oscillation. This character was much obvious from middle Pleistocene. The spatial variation of dry and wet condition changed distinctively in this basin. It was more wet in the eastern part than to the western part. This spatial change characteristic had formed from early Pleistocene or earlier. As the climatic environment of dry and cold to warm and wet in Qaidam Basin has been controlled by the winter monsoon,southeast and southwest monsoon,and influenced by the Qinghai—Xizang（Tibet） Plateau and high mountain around the basin,the dry and wet climate condition has a great difference in the Qaidam basin.

关 键 词：柴达木盆地 蒿藜比值(A/C) 新近纪 古气候重建 

分 类 号：P532[天文地球—古生物学与地层学]