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通过对藏南沉错湖芯TC1孔的研究,分析了TC1孔的粒度、TOC、TN、C/N、Fe/Mn、Sr/Ba以及环境磁学参数等环境代用指标,基本上获得了这一地区2万年以来的环境变化记录。结果显示约19 800~18 000 Cal aBP的温度下降在各指标中具有明显的反映;约16 000 Cal aBP左右,温度在一次跃动上升之后,随即出现急剧下降;约15 200~12 000 Cal aBP,是降温之后的缓慢回升过程;约12 000~9 500 Cal aBP,各种指标均显示湖区环境处于不适宜阶段,特别是11 600~10 400 Cal aBP,湖区环境显著恶化。进入全新世后,湖区环境经历了3次明显的暖期(约9 500~7 600 Cal aBP、约6 800~5 800 Cal aBP、约4 800~3 800 Cal aBP) 和2次冷期(约7 600~6 800 Cal aBP、约5 800~4 800 Cal aBP),呈现出暖干/冷湿的交替规律,具有南亚季风(西南季风) 区气候变化的特征。沉错湖区2万年来的气候环境变化序列中的某些特征时段与格陵兰冰芯记录和青藏高原其他记录相比具有较好的一致性,反映了湖区及藏南地区的气候环境演变特征具有全球性特征。
Based on the study of the TC1 pore in the core of the Shennan Lake in southern Tibet, the environmental proxy indexes such as grain size, TOC, TN, C / N, Fe / Mn, Sr / Ba and environmental magnetic parameters of TC1 pore were analyzed. Environmental records of changes in a region over 20000 years. The results show that the temperature drop from about 19 800 to 18 000 Cal aBP is obviously reflected in all the indexes; about 16 000 Cal a BP, the temperature drops sharply immediately after a rise in temperature; about 15 200 ~ 12 000 Cal aBP , Which is a slow recovery after cooling; about 12 000 ~ 9 500 Cal aBP. Various indicators show that the lake environment is in an unfit stage, especially 11 600 ~ 10 400 Cal aBP, and the lake environment is significantly deteriorated. After entering the Holocene, the lake environment experienced three distinct warm periods (about 9 500 ~ 7 600 Cal a BP, about 6 800 ~ 5 800 Cal aBP, about 4800 ~ 3800 Cal aBP) and two cold periods 7 600-8 800 Cal aBP, about 5 800-4 800 Cal aBP), showing the alternating law of warm-dry / cold-wetness and having the characteristics of climate change in the South Asian monsoon (southwest monsoon). Some characteristics of climate change sequences in the Changchu Lake region over 20000 years have some consistency with those of the Greenland ice core record and other records of the Qinghai-Tibet Plateau, reflecting the evolution of climate and environment in the lake and southern Tibet. Sexual characteristics.