Research on the carbon isotopic composition of organic matter from Lake Chenghai and Caohai Lake sediments  

作　　者：ZHU Zhengjie CHEN Jing＇an ZENG Yan LI Hang YAN Hui REN Shicong 

机构地区：[1]The State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China [2]Chongqing Key Laboratory ofExogenic Minerallization and Mine Environment, Chongqing Institute of Geology and Mineral Resources, Chongqing 400042, China [3]Chongqing Research Center of State Key Laboratory of Coal Resources and Safe Mining, Chongqing 400042, China [4]Graduate School of Chinese Academy of Sciences, Beijing 100049, China [5]College of Urban Planning and Environment Science, Xuchang University, Xuchang 461000, China

出　　处：《Chinese Journal Of Geochemistry》2011年第1期107-113,共7页中国地球化学学报

基　　金：supported by the National Basic Research Program of China (Grant No. 2006CB403201);the National Natural Science Foundation of China (Grant No. 40673068)

摘　　要：The carbon isotopic composition of organic matter from lake sediments has been extensively used to infer variations in productivity. In this paper, based on the study of the contents and δ13C values of organic matter in different types of lakes, it has been found that δ13C values of organic matter have different responses to lake productivity in different lakes. As to the lakes dominated by aqutic macrophytes such as Lake Caohai, organic matter becomes enriched in 13C with increasing productivity. As to the lakes dominated by aquatic algae such as Lake Chenghai, δ13C values of organic matter decrease with increasing productivity, and the degradation of aquatic algae is the main factor leading to the decrease of δ13C values of organic matter with increasing productivity. Therefore, we should be cautious to use the carbon isotopic composition of organic matter to deduce lake productivity.The carbon isotopic composition of organic matter from lake sediments has been extensively used to infer variations in productivity. In this paper, based on the study of the contents and δ13C values of organic matter in different types of lakes, it has been found that δ13C values of organic matter have different responses to lake productivity in different lakes. As to the lakes dominated by aqutic macrophytes such as Lake Caohai, organic matter becomes enriched in 13C with increasing productivity. As to the lakes dominated by aquatic algae such as Lake Chenghai, δ13C values of organic matter decrease with increasing productivity, and the degradation of aquatic algae is the main factor leading to the decrease of δ13C values of organic matter with increasing productivity. Therefore, we should be cautious to use the carbon isotopic composition of organic matter to deduce lake productivity.

关 键 词：碳同位素组成 有机物质 澄海 海底泥 湖泊沉积物 水生植物 生产力 有机质 

分 类 号：P736.211[天文地球—海洋地质] X703[天文地球—海洋科学]