【摘要】 根据新疆乌伦古湖钻孔剖面高分辨率的孢粉研究,得出全新世以来研究区的气候经历了四个大的阶段:约9.99—7.72cal.kaBP期间,气候温暖干旱;7.72—3.62cal.kaBP,气候由温和偏湿逐渐转向温暖偏干;3.62—1.24cal.kaBP,气候由寒冷干旱逐渐转向寒冷偏湿到温和湿润;1.24cal.kaBP至今,气候总体上温和干旱。在这四个大阶段的气候背景下,还存在8.90cal.kaBP和8.35cal.kaBP左右、3.62—2.80cal.kaBP期间、0.82—0.45cal.kaBP期间和约0.23cal.kaBP时的突然变冷事件。本剖面的孢粉组合在约9.99—7.72cal.kaBP期间反映的是湖区的植被,早期为以芦苇为主的水生植物群落,随后演替成以黑三棱为主的水生植物群落;自7.72cal.kaBP以后,孢粉组合反映的是区域植被,与气候相应的区域植被依次经历了荒漠草原→荒漠→荒漠草原→草原或荒漠草原→草原→荒漠→荒漠草原的多次演替。更多还原

【Abstract】 According to high resolution sporopollen analysis from a core of the Wulungu Lake, Xinjiang, we have discovered that the climate since Holocene in the research region can be divided into four stages. During about 9.99—7.72 cal. kaBP, climate was mild and dry. Stage of 7.72—3.62 cal. kaBP, climate gradually turned to warm and moderately dry condition from mild and moderately humid condition. In 3.62—1.24 cal. kaBP climate shifted from cool and dry condition into cool and moderately humid, and then to mild and humid condition. From 1.24 cal. kaBP to today, climate was generally mild and dry condition. During the four stages, some abrupt cooling events can be identified at time slices of 8.90, 8.35, 3.62? ?.80, 0.82—0.45 and 0.23 cal. kaBP. During about 9.99—7.72 cal. kaBP, sporopollen assemblage can only reflect aquatic vegetations around the Wulungu Lake which evolved from domination of Phragmites into aquatic flora dominated by Sparganium. Since 7.72 cal. kaBP, the assemblage can represent regional vegetation. Corresponding to climate, regional vegetation experienced several changes as following successionally: desert-steppe vegetation → desert vegetation → desert-steppe vegetation → steppe or desert vegetation → steppe vegetation → desert vegetation → desert-steppe vegetation.更多还原