赛里木湖沉积物有机质变化特征及其环境信息

在分析赛里木湖湖泊沉积物中氮含量(TN)、有机碳含量(TOC)及其碳同位素(δ~(13)C_(org))以及色素等指标的变化特征的基础上,结合沉积物中有机指标的环境意义的探讨,揭示了新疆赛里木湖湖泊沉积物中有机质所蕴含的环境信息.赛里木湖沉积物中总有机碳含量、总氮含量的变化反映了流域初级生产力的变化,沉积物色素变化是有机质保存条件的指标,间接指示了湖泊-流域水热配置环境.有机碳同位素(δ~(13)C_(org))反映了湖泊内外源的混合信息.结合有序样品聚类分析方法,可以将赛里木湖近代环境划分为四大发展阶段:1、各有机指标相对稳定;2、各有机指标明显波动;3、各有机指标显著增加;4、各有机指标快速增加.

Variation of the organic matter content of the sediment abstracted from Sayram Lake and its environmental significance

Using the organic indexes of sediment abstracted from Sayram Lake,including total nitrogen,pig-ment,total organic carbon and its isotope,in combination with the environmental significance of sediment organ-ic indexes,the environmental information contained in the organic matter is revealed.The variation of the total organic carbon content and total nitrogen content in Sayram Lake sediment show the fluctuation of lake′s primary productivity.The pigment indicates the preservation conditions of organic matter,which indirectly indicates the water-heat allocation in the lake-watershed;Organic carbon isotope reflect the lake mixture information of inter-nal and external sources.Combined with the orderly sample clustering analysis,the modern Sayram Lake envi-ronment can be divided into four stages.In the first stage,every organic index was relatively stable;in the second stage,every organic index fluctuated obviously;in the third stage,every organic index increased signifi-cantly;in the fourthly stage,every organic index increased rapidly.