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利用活塞采样器在位于青藏高原西南部塔若错60 m水深处获得3.1 m沉积岩芯.通过AMS14C测年、花粉、粒度和无机碳分析,恢复了青藏高原西南部全新世以来的植被和气候变化.结果显示,全新世初期(10200~8900 cal a BP),植被由高寒草原向高寒草甸转换,气候由冷干向暖湿发展;全新世早期(8900~7400 cal a BP),植被由高寒草甸到高寒草原的转换,气候相对干旱,但偏暖;全新世中期(7400~3300 cal a BP),植被从高寒草原向高寒草甸或草甸化草原转换,气候以冷湿为主;全新世晚期(3300 cal a BP至今),植被逐渐被高寒草原取代,气候变得寒冷干旱.塔若错全新世早期和中晚期的特征气候事件表明,该地区明显受到西风区环境变化的影响,而在全新世中期更多受印度季风环流控制.尤其是中晚全新世塔若错的湖泊沉积环境记录对于进一步阐述西风/季风在该地区的影响程度具有非常重要的意义.
A 3.1 m sedimentary core was obtained using a piston sampler at a water depth of 60 m in Taro Wakuo, southwest of the Qinghai-Tibetan Plateau. Vegetation and climate changes since the Holocene in the southwestern Tibetan Plateau were restored by AMS14C dating, pollen, grain size and inorganic carbon analysis The results showed that during the early Holocene (10200 ~ 8900 cal a BP), the vegetation changed from alpine grassland to alpine meadow, and the climate developed from cold to warm. The early Holocene (8900 ~ 7400 cal a BP) In the mid-Holocene (7400-3300 cal BP), the vegetation changed from alpine grassland to alpine meadow or meadow steppe with the climate being mainly cold and humid. Vegetation was gradually replaced by alpine grasslands and the climate became cold and dry during the late Holocene (3300 cal a BP so far). The characteristic climate events in the early and late Holocene of the Tarim Basin show that the area is significantly affected by the environmental changes in the westerly region, And more controlled by the Indian monsoon circulation in the mid-Holocene, especially the record of the sedimentary environment of Lake Tazuo in the mid-late Holocene is of great significance for further elaborating the influence of the westerly / monsoon in this area.