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采用索氏抽提法提取纳木错NMLC-1孔湖芯沉积物中的正构烷烃,利用GC/MS进行了测试.在已经建立的深度-年代曲线基础上,通过分析正构烷烃的组成与含量,结合TOC,TN和CaCO3等环境代用指标,重建了纳木错湖区约8.4ka以来的环境变化历史.结果表明:约8.4~6.7kaBP期间,环境较温暖,降水呈增加趋势,末期变冷干.约6.7~2.9kaBP期间可分为两个亚期,早期温暖湿润,至6.0kaBP左右达到环境最适宜期;晚期温度波动降低,陆生植被和沉水植物退化,以3.0kaBP左右的冷事件结束.约2.9kaBP~现在,冷暖交替,1.4kaBP左右开始趋于干燥,600~400aBP间的降温体现了小冰期特征.
Soxhlet extraction was used to extract the n-alkanes in the core deposits of NMLC-1 pore in the Nam Co. The GC / MS was used to test the n-alkanes. Based on the established depth-age curves, by analyzing the composition and content of n-alkanes, , The history of environmental changes since the last 8.4 ka in the Nam Co Lake region was reconstructed by using environmental proxy indexes such as TOC, TN and CaCO3.The results show that the environment is warm during the period of 8.4 ~ 6.7kaBP, the precipitation tends to increase, 6.7 ~ 2.9kaBP period can be divided into two sub-periods, the early warm and humid, to 6.0kaBP or so to reach the most appropriate environment; late temperature fluctuations decreased, terrestrial vegetation and submerged macrophytes degenerated, with about 3.0kaBP cold end of the event. About 2.9kaBP ~ Now, alternating between warm and cold, 1.4kaBP or so began to dry, cooling between 600 ~ 400aBP reflects the characteristics of the Little Ice Age.