湖泊沉积物中有机碳同位素特征及其古气候环境意义  

The Characteristics of Compositions of the Organic Matter δ^(13)C in Lake Sediments and Its Paleoclimatic Environmental Significance

作　　者：王秋良[1] 谢远云[1] 梅惠[1] 

机构地区：[1]中国地质大学地球科学学院,武汉430074

出　　处：《安全与环境工程》2003年第4期17-21,共5页Safety and Environmental Engineering

基　　金：国家自然科学基金 (编号 :40 172 0 61)资助

摘　　要：湖泊沉积物中有机碳同位素受到湖水化学性质 (pH值、硬度等 )、湖区气温和降水、光照条件、大气压力、CO2 分压、盐分及营养元素、有机质的来源、有机质的保存、后期改造及成岩作用等诸多因素的影响 ,其中有机质的来源、温度和大气压力是影响有机质δ13 C值的主导因素。有机质碳同位素与气候条件存在着一定联系。13 C值高 ,一般对应于气候的暖期 ;13 C值低则对应冷期。但实际中比较复杂 ,两者之间不存在固定的模式 ,因而 ,湖泊沉积物有机质13 C在指示古气候变化上存在多解性、复杂性和混乱性。本文利用国内外的一些研究成果 ,对湖泊沉积物有机质13 C的组成特征及其古气候环境意义的研究现状进行了详细论述。In this paper, the characteristics of compositions of organic matter δ 13C in lake sediments and its relation with the environment and climate are discussed. It is shown that the organic matter δ 13C remaining in lake sediments reveals some important environmental information, such as variations of CO 2 concentration in atmosphere, fluctuations of lake water level, changes of ecology and vegetation in the lake district and so on. There are many influential factors for this organic matter, such as chemical characteristics of lake water, temperature and precipitation in lake area, light conditions, atmospheric pressures, partial pressures of CO 2, salinity and nutritive elements, the reservation of lake sediments and so on; but among them, the source of organic matter, temperature and atmospheric pressures play the dominant role. The organic matter δ 13C is related to the weather to some extent. Generally, during the colder climatic episodes the δ 13C values are low. But actually there is a complex and inconstant relationship between them, and,therefore, the explanations of influence of the organic matter δ 13C in lake sediments on paleosclimatic variations are multiple,complex and confused. The composition features, influential factors and the paleoclimate environmental significance of the organic matter δ 13C in lake sediments are discussed in detail in this paper.

关 键 词：湖泊沉积物 有机质碳同位素 古气候 

分 类 号：X142[环境科学与工程—环境科学]