青藏高原沱沱河至昆仑河地区晚更新世以来孢粉记录的古环境信息  

Paleoenvironmental changes since the late Pleistocene based on sporopollen records in the area from the Tuotuo River-Kunlun River, Qinghai-Tibet Plateau

作　　者：赵振明[1] 彭伟[2] 邓中林[2] 李荣社[1] 王毅智[2] 朱迎堂[1] 

机构地区：[1]中国地质调查局西安地质矿产研究所,陕西西安710054 [2]青海省地质调查院,青海西宁810012

出　　处：《地质通报》2006年第12期1469-1474,共6页Geological Bulletin of China

基　　金：中国地质调查局<青藏高原北部空白区基础地质综合研究>项目(编号:1212010510110);1:25万沱沱河幅(编号:200213000001);1:25万可可西里幅(编号:20001300009211);"1:5万万宝沟等3幅(编号:20001300010071)区域地质调查"项目联合资助

摘　　要：根据对青藏高原沱沱河流域的雅西错湖湖相沉积、西金乌兰湖岸边的湖相沉积和昆仑河河流相沉积记录的晚更新世以来的孢粉资料的对比分析,该地区2种标志性花粉蒿属(Artemisia)、藜科(Chenopodiaceae)的百分含量表现出明显的负相关性,从南向北、从老到新,孢粉的种类、乔木花粉的数量逐渐减少,禾本科(Gramineae)花粉百分含量逐渐降低,蕨类孢子数量少;在研究区南部晚更新世早期出现了以白刺属(Nitraria)为代表的干旱灌丛草原植被,在研究区3～1万年之间出现了以蒿属、禾本科为代表的干偏湿的草原植被;总体上,根据晚更新世的孢粉恢复的古环境,南部地区比北部地区偏湿。这一特征对恢复青藏高原晚更新世的古环境具有重要的参考意义。Comparative study of the data of the late Pleistocene sporopollen in lacustrine deposits of Yaxi Co Lake in the reaches of the Tuotuo River and lacustrine deposits on banks of the Xijir Ulan Lake and fluvial deposits of the Kunhm River in the Qinghai-Tibet Plateau indicates that there is a pronounced negative correlation in percentages between the two pollen markers Artemisia and Chenopodiaceae in the area. From south to north and from older to younger strata, the species of sporopollen and number of arbores diminished gradually, the percentages of pollen of Gramineae decreased progressively and spores of fern were scarce. The dry shrubs-grassland vegetation represented by Nitraria appeared in the southern part of the study area during the early part of the late Pleistocene. Dry-wet grassland vegetation represented by Artemisia and Gramineae appeared at 30-10 ka BP in the area. In general, the southern part of the area was wetter than the northern part according to the paleoenvironment reconstructed by the late Pleistocene sporopollen analysis. This feature has great significance for the reconstruction of the paleovegetation and paleoenvironmental of the Qinghai-Tibet Plateau during the late Pleistocene.

关 键 词：青藏高原 沱沱河至昆仑河地区 孢粉记录 晚更新世 古环境 

分 类 号：P534.63[天文地球—第四纪地质学] Q914.81[天文地球—古生物学与地层学]