内蒙古克什克腾旗浩来呼热古湖泊全新世以来的环境演变

Environmental evolution since the Holocene in the Haolaihure ancient lake,Keshiketengqi,Inner Mongolia,China

利用位于中国北方季风尾闾区的浩来呼热古湖泊沉积物中的硅藻化石重建了全新世以来的环境演变历史。根据硅藻组合的变化,可将浩来呼热古湖泊全新世以来的环境演变过程划分为6个阶段:阶段Ⅰ(12.1～11.5cal ka BP),气候以寒冷为主;阶段Ⅱ(11.5～8.6cal ka BP),温度有所回升,但存在一定的冷暖波动;阶段Ⅲ(8.6～6.7cal ka BP),气候仍相对偏凉,且比较干燥;阶段Ⅳ(6.7～5.8cal ka BP),气候开始转温;阶段Ⅴ(5.8～2.9cal ka BP),气候温暖偏湿,为全新世气候最适宜期;阶段Ⅵ(2.9～0.2cal ka BP),气候趋于凉干,湖水也越来越浅,最终在0.2cal ka BP前后干涸消失。

Through the analysis of fossil diatom in the sediments of Haolaihure ancient lake, which is located in the monsoon fringe area in North China, the environmental evolution has been reconstructed since the Holocene. According to the variations of the diatom assemblages, the environmental evolution of Haolaihure ancient lake since the Holocene has been divided into 6 stages. Ⅰ （12.1- 11.5 cal. ka B.P.）, the climate was cold; Ⅱ （11.5-8.6 cal. ka B.P.）, the temperature increased, but still with cold and hot fluctuation; Ⅲ （8.6-6.7 cal. ka B.P.）, the climate was still relatively cool and dry; Ⅳ（6.7-5.8 cal. ka B.P.）, the climate began to be warm; Ⅴ（5.8-2.9 cal. ka B.P.）, the climate was warm and humid, and it was the Holocene optimum; Ⅵ（2.9-0.2 cal. ka B.P.）, the climate trended to be cool and dry, and the lake level decreased gradually and finally dried out at about 0.2 cal. ka B.P..