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可以指示陆源和海源有机质的类脂生物标志物是重建晚第四纪海洋生态环境的良好指标.但目前为止,类脂生物标志物在东海水体及沉积物中的对比研究还很缺乏.针对这一问题,于2010年6月10日至6月20日在长江口及东海陆架区采集了表层颗粒物和沉积物.研究其所含类脂生物标志物的分布并对比分析.研究的类脂生物标志物包括长链奇碳数正构烷烃(主要来自陆源高等植物),长链烯酮(来自颗石藻),菜子甾醇(主要来自硅藻),甲藻甾醇(主要来自甲藻).研究结果表明表层颗粒物中的长链正构烷烃并未表现出奇偶优势(CPI25-33平均值为1.2),主要可能受到石油烃类的影响,从而使得长链奇碳数正构烷烃对陆源有机质的指示作用发生偏差.但是表层沉积物中的长链正构烷烃表现出明显的奇偶优势(CPI25-33平均值为2.9),并且长链奇碳数正构烷烃有近岸高离岸低的分布趋势.与长江陆源物质对东海的输入模式相似.颗粒物与沉积物中长链正构烷烃的分布特征不同,可能主要与石油污染、时间尺度和有机质来源的空间差异有关.研究结果表明东海表层颗粒物中海源生物标志物菜子甾醇和甲藻甾醇的分布与以往浮游植物调查结果基本一致,在研究区域中部南北各存在一高值区,主要受控于初级生产.表层沉积物中这两种海源生物标志物的分布与表层颗粒物不同.在研究区域内呈现近岸和外海高,中间低的趋势.导致表层颗粒物和沉积物中海源生物标志物不同分布的原因为:表层颗粒物中的有机质主要由某个季节在表层产生的.而表层沉积物中的有机质主要是反映了年或者几年平均的水柱输出生产力.此外,表层的有机质在输出到沉积物中的过程中还受到迁移、转化、降解以及粒度等沉积环境因素的影响.因此某个季节的表? “,”Lipid biomarkers indicating terrestrial and marine organic matter are usually used to reconstruct the changes of late Quaternary marine environment. However, there are few studies about lipid biomarkers in both seawater and sediments of the East China Sea. In this study, surface particulates and sediments were collected in Changjiang Estuary and the East China Sea shelf from June 10 to June 20, 2010, and lipid biomarkers from these samples were measured and compared. Analyzed biomarkers, included long-chain odd-carbon n-alkanes (mainly originated from terrestrial higher plants), long-chain alkenones (produced by coccolithophores), brassicasterol (mainly produced by diatoms), dinosterol (mainly produced by dinoflagellates ). The results show that long-chain n-alkanes from surface particulates have no obvious odd-even dominance (average CPI25-33 is 1.2), which could be affected by petroleum hydrocarbons and bias the indication of long-chain odd-carbon n-alkanes for terrestrial organic matter. However, long-chain n-alkanes from surface sediments have significant odd-even dominance (average CPI25-33 is 2.9 ), and long-chain odd-carbon n-alkanes have higher content near-shore and seaward low content, similar to the input pattern of Changjiang material into the East China Sea. The difference of long-chain n-alkanes CPI25_33 values in particulates and sediments is likely related to the influence of petroleum pollution, time scale of the samples and the space difference of organic matter source. The results indicate that the distribution of brassicasterol and dinosterol in surface particulates of the East China Sea is consistent with previous phytoplankton investigation, with high values in the north and the south of study area, mainly controlled by primary production. The contents of brassicasterol and dinosterol in surface sediments have high values in near-shore and open sea while have low values in the middle of study area, which is different from those in particulates. Different distributions