全新世湖泊沉积物TOC、C/N和δ^(13)C_(org)对千年尺度气候变化的响应  

The Response of Organic Geochemical Proxies in Holocene Lake Sediments to Millennial-scale Climate Change

作　　者：周雪花[1] 李育[1] 张成琦[1] 王岳[1] 

机构地区：[1]兰州大学资源环境学院干旱区水循环与水资源研究中心,甘肃兰州730000

出　　处：《盐湖研究》2013年第4期1-9,共9页Journal of Salt Lake Research

基　　金：国家自然科学基金项目(41371009;41001116);兰州大学中央高校基本科研业务费专项资金项目(LZUJBK-2013-127)共同资助

摘　　要：湖泊沉积物有机地化指标在古气候解释中具有复杂性和多解性。TOC、C/N和δ13C org作为3种常用的有机地化指标,现已广泛运用于东、中亚全新世气候变化研究中。以这3种指标为例综述了东、中亚全新世湖泊沉积有机地化指标的变化机制及影响因素。根据数据的综合分析与对比,大部分湖泊全新世沉积物TOC百分含量较高时,C/N比值也较高,这与沉积物有机质的来源有关,因两者TOC和C/N作用机制不同,也存在少数湖泊,其两者对应关系不明显;同一湖泊δ13C org与TOC及δ13C org与C/N对应关系相似;由于不同区域影响有机地化指标的因素不同,TOC、C/N和δ13C org间的关系存在区域差异,据此可将研究区分为中纬度地区、青藏高原区和低纬度季风区。上述区域规律存在于研究中所选的大部分湖泊,由于有机地化指标作用机理的复杂性,也存在不符合这种规律的湖泊,因而上述结论有待于进一步讨论。The explanation of organic geochemical proxies in lake sediments is complicated in reconstruc- tion of paleoclimate. TOC, C/N and δ13Corg are three frequently-used organic geochemical proxies, being used widely for studying Holocene climate change in East and Central Asia. This paper takes these three proxies for example to discuss the influencing factors and mechanisms of Holocene lacustrine geochemical processes in the study region. According to the results, TOC and C/N show simultaneous changes at a same lake,which is affected by sources of organic matter; relationship between δ13Corg and TOC is similar to that of δ13Corg and C/N,but there are some differences between different parts East and Central Asia, since the influencing factors of proxies are different. Based on the characteristics of the relationships between or- ganic geochemical proxies, the study region can be divided into three sub-regions： the mid-latitudes, the Qinghai-Tibet Plateau and the low-latitude monsoon region. The influencing factors of organic geochemical proxies are different among the three sub-regions.

关 键 词：湖泊沉积 全新世 有机地球化学指标 气候变化 东 中亚 

分 类 号：P534.63[天文地球—第四纪地质学]