辽东湾北部地区海洋沉积物中PAHs分布特征研究

发布时间：2018-03-08 04:08

本文选题：多环芳烃　切入点：海洋沉积物　出处：《大连海事大学》2016年硕士论文　论文类型：学位论文

【摘要】：多环芳烃(PAHs)是广泛存在于环境中的一种典型的持久性有机污染物。虽然它在环境中的含量很低,但由于它可以长时间富集在人体内,且具有三致作用,因而日渐受到人们的关注,特别是其中有些物质有较强的致癌性。随着人类社会的发展,海洋污染越来越严重。PAHs作为其中一种难降解易富集的污染物,特别容易通过食物链富集在整个生态系统中,威胁生物种群,特别是容易威胁到人类自身的生命健康。辽东湾作为工业区,在我国的经济发展中发挥着重要的作用,长期受到人类生产生活的影响。本文以大凌河口、双台子河口柱状沉积物为研究对象,研究PAHs在辽东湾北部地区的污染状况,希望能够为辽东湾区域的环境监测提供科学依据。通过对实验的结果分析与讨论得到以下主要结论:(1)经210Pb定年法估算,辽东湾北部地区沉积物的沉积速率为1.12cm/a。PAHs的时间分布情况与经济发展趋势基本符合,近年来有明显增长趋势。其中中双台子河口 2个海洋沉积柱中多环芳烃含量分别在39.79～503.52ng/g、98.14～388.78ng/g之间,平均值分别为155.81ng/g、182.35ng/g。大凌河口海洋沉积柱中多环芳烃含量在207.13～882.15ng/g之间,平均值为484.76ng/g。大凌河口污染程度要高于双台子河口。组成特征中均表现四环、五环占优,但大凌河口多环比重高。与同类文献比较,辽东湾北部地区PAHs总体污染情况远小于国外一些污染严重的地区,略高于我国长江、渤海等地,处在比较低的水平。(2)低分子量PAH化合物与高分子量PAH化合物之间的比值(LMW/HMW值均小于1),可以初步推测本区多环芳烃的来源主要为高温燃烧过程。通过特征分析法比较 Ant/(Ant+Phe)、BaA/(BaA+Chy)、Fth/(Fth+Pyr)、Indeo/(Indeo+Bghip)的比值范围,以及进一步的主成分分析法判断PAHs的污染来源,3个海洋沉积柱得到的结果基本相同,即大辽河北部地区多环芳烃污染主要来源为煤、木材燃烧,小部分来自石油及其精炼产品的燃烧,也有来自汽车尾气的排放。但大凌河口污染来源更加复杂。(3)通过效应区间低、中值法,平均效应中值商法量等方法的研究结果可以看出,辽东湾北部地区海洋沉积物PAHs的生态风险很弱,总体有上升趋势。其中苊、芴、茚苯[1,2,3-cd]芘可能存在对生物的负影响。但通过毒性当量分析表明,PAHs毒性当量高于荷兰土壤标准,存在生态风险。分析结果的差异需要进一步的研究。且大凌河口地区的生态风险要高于双台子河口地区,需要引起关注。
[Abstract]:Polycyclic aromatic hydrocarbons (PAHs) is a typical persistent organic pollutant widely found in the environment. Although its content in the environment is very low, it can be enriched in human body for a long time and has three effects. With the development of human society, the marine pollution becomes more and more serious. It is particularly easy to enrich in the whole ecosystem through the food chain, threatening the biological population, especially the life and health of mankind itself. As an industrial zone, Liaodong Bay plays an important role in the economic development of our country. In this paper, the columnar sediments of Daling River estuary and Shuangtaizi estuary are taken as research objects to study the pollution status of PAHs in the northern part of Liaodong Bay. It is hoped to provide scientific basis for environmental monitoring in Liaodong Bay. By analyzing and discussing the experimental results, the following main conclusions: 1) have been estimated by 210Pb dating method. The time distribution of sediment deposition rate of 1.12cm / a.PAHs in the northern part of Liaodong Bay is basically consistent with the trend of economic development, and there is an obvious increasing trend in recent years. The polycyclic aromatic hydrocarbons (PAHs) in the two marine sediment columns in the Zhongshuangtaizi estuary are between 39.79 ~ 503.52 ng / g ~ (-1) ~ 98.14 ~ 388.78 ng 路g ~ (g / g), respectively. The average value is 155.81 ng / g / g 182.35 ng / g respectively. The polycyclic aromatic hydrocarbons (PAHs) content in the Daling River estuary marine sediment column is between 207.13 and 882.15 ng / g, and the average value is 484.76 ng / g. The pollution level in the Daling River mouth is higher than that in the Shuangtai River estuary. Compared with the similar literature, the overall PAHs pollution in the northern part of Liaodong Bay is much smaller than that in some foreign regions, and is slightly higher than that in China's Yangtze River and Bohai Sea. The ratio of low molecular weight PAH compounds to high molecular weight PAH compounds is less than 1%. It can be preliminarily speculated that the origin of polycyclic aromatic hydrocarbons in this area is mainly high temperature combustion process. Compared to the ratio range of Baa / Baa / Baa / Fth / Fth Pyrr / Indeo Bghipp, The results obtained from the three marine sediment columns are basically the same, that is, the main sources of PAHs pollution in the northern part of the Daliaohe River are coal and wood combustion. A small part comes from the combustion of petroleum and its refined products, as well as from automobile exhaust emissions. However, the pollution sources in the Daling River mouth are more complicated. (3) the results of research on the low effect range, the median method, the average effect median quotient method and other methods can be seen. The ecological risk of PAHs in marine sediments in the northern part of Liaodong Bay is very weak, and there is a general upward trend, in which acenaphthene, fluorene and indenyl pyrene may have negative effects on organisms, but the toxicity equivalent of PAHs is higher than that of Dutch soil standards. There are ecological risks. The difference of the analysis results needs further study, and the ecological risk in Daling River estuary is higher than that in Shuangtaizi estuary, which needs to be paid attention to.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：X55

【相似文献】