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利用西藏南部普莫雍错深水湖区获取的3.8m长湖芯,对湖芯中25个样品的植物碎屑进行筛选和有机碳同位素测定,在确定植物来源的前提下进行了14C测定,结合表层样品的过剩210Pb衰变计算的沉积速率对整个湖芯的14C测年及其碳库效应进行了系统校正,结果显示该湖芯完整地覆盖了19calkaBP以来的时间尺度.通过对湖芯TOC,IC,粒度和孢粉的分析,发现该湖在16.2calkaBP之前为一个水深较浅的湖泊,尽管温度升高导致冰川开始融化,湖区环境仍然具有冷干的特征;16.2～11.8calkaBP,沉积环境剧烈而频繁的波动,14.2和11.8calkaBP左右的2次冷事件可能是老仙女木和新仙女木事件的反映.11.8calkaBP之后,已经形成了现今状态的深水湖泊,冰川融水的补给使得湖泊水温较低,受到湖泊水体影响的沉积物环境代用指标对温暖条件的响应并不明显.通过普莫雍错湖与西藏南部相同时代的不同湖泊沉积物记录的比较,发现末次冰消期开始的气候转暖对青藏高原东南部影响更加显著,反映了西南季风自冰消期以后逐渐加强、向高原内部推移的过程,以冰川融水补给为主的湖泊对冷事件的响应更加明显.全新世以来,西南季风对整个西藏南部区域发挥着控制性影响.
Based on the 3.8 m lake core obtained from the deep Puhuo Lake in the south of Tibet, 25 samples from the lake were screened and the organic carbon isotopes were determined. The 14C was determined on the basis of determining the source of plants. The surface layer Systematic calibration of the 14C dating of the entire lake core and its carbon pool effect has been systematically calibrated with the calculated 210Pb decay rate of the sample and the results show that the lake core completely covers the time scale since 19calkaBP.Through the analysis of TOC, IC, Particle size and sporopollen analysis showed that the lake was a shallow water lake before 16.2calkaBP. Although the glacier began to melt after the temperature rose, the lake environment still had the characteristics of cold and dry; 16.2 ~ 11.8calkaBP, the depositional environment was intense and frequent , The second cold events of 14.2 and 11.8calkaBP may be the reflection of the old fairy wood and the new fairy wood events.11.8 After the calkaBP, a deep-water lake has been formed in the current state. The supply of glacial meltwater makes the lake water temperature lower, Sediment environmental proxy indicators affected by lake water have no obvious response to warm conditions. Through the different lakes of the same age in Pumayongmao Lake and southern Tibet It is found that the climate warming at the beginning of the last ice-cooling period is more significant in the southeastern part of the Qinghai-Tibet Plateau, reflecting the gradual strengthening of the southwest monsoon since the disappearance of ice and the shift to the interior of the plateau, mainly by glacial melt recharge Responses by lakes to cold events became more pronounced, and since the Holocene, the southwest monsoon has had a controlling impact on the entire southern region of Tibet.