内蒙古西乌旗地区中——晚更新世孢粉记录及其古气候意义  

Sporopollen record during Mid-Late Pleistocene from West Ujimqin Banner,Inner Mongolia,and its paleoclimatic significance

作　　者：杨兵 陈喜庆 葛天助 韦一 刘迁 YANG Bing;CHEN Xiqing;GE Tianzhu;WEI Yi;LIU Qian(Cores and Samples Centre of Nature and Resources,Langfang 065201,Hebei,China;School of Safety Engineering,North China Institute of Science and Technology,Langfang 065201,Hebei,China)

机构地区：[1]自然资源实物地质资料中心,河北廊坊065201 [2]华北科技学院安全工程学院,河北廊坊065201

出　　处：《地质通报》2024年第6期1047-1058,共12页Geological Bulletin of China

基　　金：国家自然科学基金项目《青藏高原始新世—渐新世古海拔演化的介形类和同位素证据》(批准号:41702366);中国地质调查局项目《实物地质资料采集更新与数字化应用》(编号:DD20230138);中央高校基本科研业务费《古近纪华北—华南非海相介形类动物化石差异演化及其地质意义》(编号:3142018004)。

摘　　要：为重建内蒙古西乌旗地区巴音华盆地中—晚更新世之交古气候,探讨其变化规律及对全球古气候的响应,对该盆地ZK03钻孔和ZK04钻孔孢粉化石进行系统鉴定,利用有序聚类分析划分孢粉组合,结合共存因子分析法对孢粉组合定量化建立研究区的古气候参数值。鉴定出孢粉68个科属,自下而上划分出(Ⅰ)松属(Pinus)-桦属(Betula)-香蒲属(Typha)孢粉组合;(Ⅱ)栎属(Quercus)-麻黄属(Ephedra)-蒿属(Artemisia)孢粉组合;(Ⅲ)莎草科(Cyperaceae)-香蒲属(Typha)-水龙骨科(Polypodiaceae)孢粉组合。其中,组合Ⅰ、组合Ⅱ时代为中更新世,组合Ⅲ时代为晚更新世。植被类型经历了阔叶林-草原型兼有少量针叶林→阔叶林-草原型→稀树-草原型的转变。古气候经历了由相对温暖的湿润型气候到相对温凉的半干旱型气候再到相对温暖的湿润型气候的3期转变,各期分别对应的年均气温和年降雨量在数值上也体现了由高到低再到高的变化过程。其中,在中更新世/晚更新世之交,气候经历由凉到温的变化趋势,与格陵兰冰芯氧同位素所指示的全球平均温度变化趋势相耦合。In order to reconstruct the paleoclimate and explore its evolution model and response to the global paleoclimate during the Mid-Late Pleistocene in the Bayinhua Basin,West Ujimqin Banner,Inner Mongolia,the sporopollen of ZK03 and ZK04 in the basin were systematically identified.Combining Coniss analyze with Co-existence Approach,we quantitatively reconstruct the palaeoclimate parameters in research area.68 genera are identified and divided into 3 assemblages as:(Ⅰ)Pinus-Betula-Typha assemblage;(Ⅱ)Quercus-Ephedra-Artemisia assemblage;(Ⅲ)Cyperaceae-Typha-Polypodiaceae assemblage.The age of assemblageⅠand assemblageⅡwas Middle Pleistocene,while the age of assemblageⅢwas Late Pleistocene.The vegetation types experienced the transformation as broadleaved-steppe type with a small amount of coniferous forest vegetation→broadleaved-steppe type vegetation→savanna-steppe vegetation.Palaeoclimate experienced three periods of transition from relatively warm and humid climate to relatively warm and cool semi-arid climate and then to relatively warm and humid climate.The annual average temperature and annual rainfall corresponding to each period also showed a numerical process of change from high to low and then to high. The trendfrom cool to warm at the turn of the Middle Pleistocene/Late Pleistocene can be well coupled with the trend of global mean temperaturethat indicated by the oxygen isotopes of Greenland ice core.

关 键 词：西乌旗 更新世 孢粉组合 古气候 地质调查工程 共存因子分析 

分 类 号：P534.631[天文地球—第四纪地质学] P532[天文地球—古生物学与地层学]