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湖泊沉积有机质稳定碳同位素 (δ13Corg)在区域气候与环境变化方面的应用研究近年来发展迅速 ,成果令人瞩目 .保存在各类湖泊岩芯中的δ13Corg记录揭示了晚更新世以来大气CO2浓度的变化、湖泊水位波动、湖区生态与植被的变迁以及气温变化等重要环境信息 .由于造成δ13Corg值变化的影响因素较多 ,确定个湖与环境变化有关的主导因素时常有赖于其它证据的帮助 ,诸如地球化学、古湖沼学、孢粉学、分子同位素地层学等等 .前人通过研究来自不同类型湖泊、具不同曲线形态特征的δ13Corg记录 ,提出了多种环境解释模型 .本文对此作了归纳和评述 .鉴别和澄清湖泊沉积有机质的源物质以及有机物源随环境变化而发生过的变动 ,是研究δ13Corg记录环境意义至关重要的基础性工作 .由于有机质含量、碳氮比值、氢指数、生物残留物鉴别等常能提供有关湖泊有机质来源、产率、成岩作用等方面的有用信息 ,这方面的研究结果应该尽可能一并提供 ,以利于恰当地应用现有的环境解释模型 ,或者建立个湖新模型 .单体生物标志化合物鉴别通常也能为区分湖积有机质中陆生、水生、细菌生等不同碳的来源提供有用信息 .特定化合物同位素分析技术近年来成功地应用于建立单体生物标志化合物碳同位素地层学 ,为湖积有机碳同位素在生态环境演变?
The research on the application of δ13Corg to the changes of regional climate and environment in lacustrine sediments has witnessed remarkable achievements in recent years.The δ13Corg records preserved in various types of lake cores reveal the atmospheric CO2 concentrations since the late Pleistocene Changes in lake water level, changes in lake ecology and vegetation, and changes in temperature and other important environmental information.Due to the many factors that cause δ13Corg values change, determining the dominant factors associated with environmental changes in a lake often rely on other evidence, such as Geochemistry, Paleoemology, palynology, molecular isotopic stratigraphy, etc. Previous studies have proposed a variety of environmental interpretation models by studying δ13Corg records from different types of lakes and with different curve morphological features. And commentary.The identification and clarification of the source material of organic matter in lacustrine sediments and the change of organic source with the change of environment are the basic work to study the significance of δ13Corg environmental record.Because of organic matter content, C / N ratio, hydrogen index, Identification of residues and other often provide the lake organic matter , Yield, diagenesis and other useful information, the results of this research should be provided as much as possible, in order to facilitate the appropriate application of existing environmental interpretation model, or the establishment of a new lake model.Motile identification of biomarkers usually But also can provide useful information for distinguishing the different carbon sources of terrestrial, aquatic and bacterial organisms in lacustrine organic matter.Specific compounds isotope analysis techniques have been successfully applied in recent years to establish the carbon isotope stratigraphy of single biomarker compounds, Carbon isotopes in the evolution of the ecological environment?