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根据洱海湖泊沉积物有机碳稳定同位素记录,结合硅藻分析资料,恢复了近8ka来云南洱海地区的气候演化序列。结果表明:8.1kaB.P.来的气候演化分为9个阶段,伴随湖泊水位波动变化。不同区域的全新世环境演化对比显示洱海气候演变主要受季风的强弱转换和时空变迁的控制,5.9kaB.P.以前气候偏暖,与太阳辐射增强引起的北半球季风环流加强有关。洱海湖泊沉积记录的暖(温)干期对应西南季风萎缩、东亚夏季风加强;相反,温(暖)湿期对应东亚夏季风减弱、西南季风加强。洱海湖泊沉积记录中三个冷事件出现在:7.2kaB.P.、5.3kaB.P.和3.7kaB.P.左右,冷干(湿)期受亚洲冬季风加强的影响。
According to the records of organic carbon stable isotopes in the sediments of Erhai Lake and the data of diatoms, the sequence of climate evolution in Erhai Lake, Yunnan Province, was restored in the past 8 ka. The results show that: 8.1kaB. P. The evolution of the climate is divided into nine stages, accompanied by changes in lake water level fluctuations. The comparison of the Holocene environmental evolution in different regions shows that the climate change in Erhai Lake is mainly controlled by the strength and weakness of the monsoon and the change of the time and space, 5.9kaB. P. In the past, the warmer climate was associated with stronger monsoon circulation in the northern hemisphere caused by enhanced solar radiation. The warm (warm) dry period recorded in sedimentary records of Lake Erhai corresponds to the shrinkage of the southwest monsoon and the strengthening of the East Asian summer monsoon. On the contrary, the warm (warm) wet period corresponds to the weakened easter monsoon in East Asia and the enhanced southwest monsoon. Three cold events in the sedimentary records of Lake Erhai appear at 7.2 kaB. P. , 5.3kaB. P. And 3.7kaB. P. Around the cold dry (wet) by the strengthening of the Asian winter monsoon.