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

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。

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

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 ...