末次盛冰期以来青藏高原东北部共和盆地气候与环境变化研究进展

青藏高原东北部共和盆地气候与环境变化文献分析认为:末次盛冰期(14 C年龄14ka BP或16cal ka BP之前)地层沉积主要为风成砂和黄土,冰缘地貌发育,气候寒冷干燥,植被可能为干旱荒漠或荒漠草原;末次冰消期(14 C年龄14ka BP或16 cal ka BP-Younger Dryas,缩写YD事件)地层发育古土壤,湖泊水位明显上升,并显著的捕捉到冷暖事件(Blling-Allerd,缩写B/A、YD)的信息,气候趋于温暖湿润,对应植被为荒漠草原;全新世8.5ka BP(14 C年龄)之前区域温度和湿度不同程度增加,湖泊水位较高,地层发育古土壤,植被为荒漠草原或干草原;8.5～7.0ka BP(14 C年龄)风成砂出现,古土壤发育中断,气候寒冷干燥,为全新世新冰期第一期;7.0～3.0ka BP(14 C年龄)古土壤显著发育,高水位湖面出现,水热组合达到全新世最佳,植被向干草原方向演化,但期间也存在千–百年尺度的冷事件(全新世新冰期第二期);3.0ka BP(14 C年龄)以来气候向温凉(寒冷)干燥方向发展.太阳辐射等外部因素变化并触发地球系统内部各个圈层之间相互作用是区域气候、环境变化的主要驱动力.同时,对研究现状进一步剖析,阐明其存在的问题,并提出气候、环境变化研究的发展方向.

Progress of Studies of Climate and Environment Changes in Gonghe Basin,Northeastern Tibetan Plateau,since the Last Glacial Maximum Period

The literatures about the climate and environment changes of Gonghe basin in northeastern Tibetan Plateau indicate that the climate was cold and dry in the Last Glacial Maximum before the 14 ka BP(14C age) or the 16 ka cal BP,with the stratum deposit consisted of aeolians and loess,well-developed periglacial landform and vegetation dominated by the arid desert and desert steppe.During the last Deglaciation period(14 ka BP 14C age) or 16 ka cal BP to the Younger Dryas Event,abbreviated as the YD),the climate became warm and wet,with obviously risen lake level and well-developed paleosol.The warm and cold climate information(the Blling-Allerd and the YD) was found and the vegetation was dominated by the desert steppe.The warm and humid degree increased in Holocene before 8.5 ka BP 14C age,accompanying with higher lake level and developed paleosol.The vegetation was dominated by the desert steppe or the dry steppe.The climate was cold and dry in the First Neoglaciation in Holocene from 8.5 to 7.0 ka BP.The development of palesol was interrupted and the aeolian sand was formed.The optimum warm and humid degree was found in 7.0~3.0 ka BP,but cold events of millennial-centennial scale also can be seen,that is,the Second Neoglaciation in Holocene,accompanying with prominently developed paleosol,higher lake level and dry steppe vegetation.Climate has become arid and cools(cold) since 3.0 ka BP(14C ages).The primary driving force is the variation of the external factors,e.g.,the solar radiation and,as a result,induced the interaction of different circles in earth system.Meanwhile,the existing problems are discussed and the future research direction of the climate change is proposed.