一万多年来乌伦古湖地区花粉组合及其古环境

Pollen Assemblage And Environmental Changes In The Last 12000 Years In Wulungu Lake

本文通过对新疆乌伦古湖钻孔剖面进行孢粉分析研究，划分出５个花粉组合带及３个组合亚带。结合岩性特征，介形虫资料及１４Ｃ测年数据，详细讨论了一万多年来该区古气候变迁及湖泊环境演变历史，其古气候经历了由冷湿（１２～１０ｋａＢ．Ｐ．）、温干（１０～７ｋａＢ．Ｐ．）→温暖湿润（７～５ｋａＢ．Ｐ．）→温干（５～３ｋａＢ．Ｐ．）→温湿→温干→温湿（３～１ｋａＢ．Ｐ．）的变化过程。于晚冰期后期（１２～１０ｋａＢ．Ｐ．），乌伦古湖开始成湖，此后，随着气候的变化，湖泊曾出现两次较大规模的退缩，约７～５ｋａＢ．Ｐ，为一次明显的湖侵。

According to the pollen analysis from the core of Wulungu lake,.five pollen zones and three subzones have been distinguished. Accompanied with the 14C dating data and ostracode analysis, this paper concludes that the palaeoclimatic changes since late Late- pleistocene are as follow in ascending order:cold and moist (12～10ka B. P. )→temperate and dry (10～7ka B. P. )→warm and wet (7～5ka B. P. )→temperate and dry (5～3ka B. P. )→tem perate and moist (3～1ka B. P. ). Wulungu lake began to form in the later late-glacial with the climatic change followed two large scale regressions an obvious transgression occured in 7 ～5ka B. P.