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在青海省西南部青藏公路东南侧的通天河支流——布曲北岸 (33°4 4′4 5 .2″N,92°11′2 8.1″E) ,发现一条拔河 0～ 18m的湖相沉积剖面。湖相沉积物的 U系测年结果为 88.9～ 5 6 .2 ka,确定其沉积时代为晚更新世早中期。结合孢粉分析结果 ,本文探讨了青海省西部地区通天河及布曲流域晚更新世早中期的古植被与古气候。初步研究表明 ,在该剖面的下部和上部沉积期间 ,当地生长松、桦、冷杉等乔木和蒿等草本植物 ,气候比较温暖湿润。剖面中部沉积期间 ,蒿、藜、禾本科和麻黄等草原植被明显增多 ,气候凉爽干燥。剖面沉积期间气候曾经历过温暖湿润和凉爽干燥的波动。植被与气候的变化具有从末次间冰期晚期经末次冰期早冰段到末次冰期间冰段中期的特征
In the northeastern Qinghai-Tibet Highway in the southwest Qinghai-Tibet Highway Tongtianhe tributary - Buqu north shore (33 ° 4 4’4 5 .2 “N, 92 ° 11’2 8.1” E), found that a tug of 0 ~ 18m lacustrine Sedimentary profiles. The U-series dating of lacustrine sediments was 88.9-5.62 ka, confirming that the sedimentary age was early-late Pleistocene. Based on the results of sporopollen analysis, the paper discussed the paleontology and palaeoclimate in the mid-late Pleistocene of Tongtianhe and Buqu Watersheds in western Qinghai Province. Preliminary studies have shown that during the deposition of the lower and upper parts of the profile, the herbaceous plants such as arbor and Artemisia grow pine, warm and humid climate locally. During the deposition in the middle part of the profile, the vegetation of Artemisia, Quinoa, Poaceae and Ephedra increased obviously and the climate was cool and dry. The climate during the profile deposition has experienced warm humid and cool dry fluctuations. Vegetation and climate changes have the characteristics of the mid-term of the ice from the last inter-ice age through the early ice last ice age to the last ice age