柘林湾养殖底泥中毒性污染物的生态风险及生物毒性评价

发布时间：2018-11-07 07:29

【摘要】：柘林湾是广东省较大规模的、典型半封闭的海水箱网养殖区。其沿岸工业污染物的陆源输入、港口通航影响和海水养殖自身污染等造成了柘林湾养殖区水体富营养化、沉积物底泥的硫化物污染和沉积物毒害污染物的富集。其中由于有机氯农药、多环芳烃和重金属污染的持久性、生态危害及人体健康风险而备受关注。本研究考察了柘林湾11个位点表层沉积物中20种有机氯农药含量分布及污染状况,采用风险商(RQ)和气象管理局(NOAA)基于沉积物质量基准(SQGs)沉积物质量标准评价了沉积物中有机氯农药的生态风险和各位点的综合生态风险,初步分析了沉积物中六六六、滴滴涕的来源以及沉积物中有机氯农药与沉积物性质参数的相关性。结果表明,柘林湾沉积物中滴滴涕的含量较高,尤其是p,p’-DDD,沉积物中滴滴涕含量超出中国海洋沉积物质量标准;沉积物中20种有机氯农药的总浓度(∑OCPs)在14.14~306.88 ng·g~(-1)之间,平均值为78.37 ng·g~(-1),其中S8位点的∑OCPs含量最高。p,p’-DDD、p,p’-DDT在多数研究位点具有必然的不利生物效应和高度生态风险,S8、S10位点处于强影响生态风险状态。柘林湾沉积物中HCHs主要来源于林丹类农药的使用;S1、S2、S10、S11位点近期均有滴滴涕的输入,其它位点滴滴涕的主要来源是早期残留或长期施用农药风化后的沉积物。沉积物中六六六、硫丹、氯丹、狄氏剂之间存在极显著正相关性,它们与沉积物TOC间存在负相关,TOC的存在促进了生物降解;p,p’-DDD与Ca的明显正相关揭示了早期施用滴滴涕随生物碳酸盐沉积;沉积物中的颗粒物逐渐增大对OCPs在沉积物中的积累和富集是不利的。定量分析柘林湾养殖区表层沉积物样品中的多环芳烃,采用RQ和SQG评价了沉积物中多环芳烃的生态风险和各位点的综合生态风险,初步分析了沉积物中多环芳烃的来源以及与沉积物相关参数的相关性,为有机污染物污染控制和环境管理等提供科学依据。结果表明,柘林湾表层沉积物各位点各类多环芳烃的含量范围是71.03-148.64 ng·g~(-1),平均值为107.87 ng·g~(-1),各PAHs的含量均值范围为0.50-18.49 ng·g~(-1)。多环芳烃的效应范围低值(ERL)的风险商(RQERL)值和各位点的根据效应范围中值(ERM)的计算得到的平均SQG商(mERM-Q)值均小于0.1,RQERL值绝大部分都小于0.1,数据结果表明,养殖区沉积物中各多环芳烃柘林湾养殖底泥中毒性污染物的生态风险及生物毒性评价在各位点处的生态风险并不明显。柘林湾养殖区底泥中多环芳烃的来源主要是木柴、煤等燃烧来源或与石油燃烧来源的混合,这也可能是由于人类活动与海航交通运输过程石油的排放。TOC、间隙水TOC、Ca的含量以及颗粒物粒径大小对多环芳烃积累和富集皆有中等以上程度的相关,且相近分子量PAHs之间存在显著相关。分析了养殖区沉积物中重金属的总量及形态分布,评价了重金属在研究区域的富集状况、生态风险、生物毒性风险、人体健康风险及其可能来源。结果显示,大部分研究位点Ni、Pb、As、Zn富集程度较大,属于污染较重的元素,在网箱和牡蛎养殖位点Ni的污染严重;采用SQGs评价法,结果显示As、Pb和Ni呈现出较高的生态风险,柘林湾西北湾口底泥中重金属处于最高生态风险;采用Hakanson指数法,结果显示Cd、As和Hg达到中度到强生态危害风险,汛洲岛周围位点底泥中重金属处于强生态危害风险;采用基于重金属形态的风险评估准则方法(RAC)评价,结果显示养殖区底泥中Cd存在很高生态危害风险,Ni主要为中等生态危害风险;通过非残留态硫化物与有机质含量的函数评价方法(∑NR-AVS)/?OC,结果表明,所有采样点沉积物中毒害重金属的风险值都小于150μmol/gOC,沉积物没有预期的不利影响;人体健康评价(HQ)结果显示,HQ值均低于1,没有潜在的健康风险暴露于金属通过摄入、吸入和非致癌风险的儿童;采用主成分分析方法分析其主要来源,结果表明,该研究区域中船只汽油和柴油的燃烧是主要的污染源。
[Abstract]:Linlin Bay is a large-scale, semi-closed mariculture area in Guangdong Province. The land-source input of the coastal industrial pollutants, the influence of the port navigation and the self-pollution of the seawater culture have resulted in the eutrophication of the water body in the culture area of the Erlin Bay, the sulfide pollution of the sediment in the sediments and the enrichment of the pollutant in the sediments. Among them, due to the persistent, ecological and human health risks of organochlorine pesticides, polycyclic aromatic hydrocarbons and heavy metal pollution. in that present study, the distribution of 20 organochlorine pesticides in the surface sediments of 11 site in the Bay of Chulin was investigated, and the pollution condition was investigated. Based on the quality standard of sediment quality (SQGs), the risk quotient (RQ) and the meteorological bureau (NOAA) were used to evaluate the ecological risk of organochlorine pesticides in the sediment and the comprehensive ecological risk of the various points. The source of DDT and the relationship between the organochlorine pesticides in the sediments and the properties of the sediment. The results showed that the content of DDT in the sediment of the sediments of the Ailin Bay was high, especially the content of the DDT in the sediments exceeded the quality standard of China's marine sediment. The total concentration of the 20 organochlorine pesticides in the sediment was between 14.14 and 306.88 ng 路 g ~ (-1), and the average value was 78. 37 ng 路 g ~ (-1). The content of OCPs in S8 is the highest. p, p '-DDD, p, p'-DDT have the necessary adverse biological effect and high ecological risk in most sites. The main source of HCHs in the sediments of the Ailin Bay is the use of the pesticides in the lindane. In the near term, the sites of S1, S2, S10, and S11 all have the input of DDT, and the main source of DDT is the early residual or long-term application of the sediments after weathering. There was a significant positive correlation between the contents of 6, 6, S, Cl, and D in the sediment, and there was a negative correlation between the TOC and TOC, and the existence of TOC promoted the biodegradation; p, p '-DDD and Ca were positively related to the early application of DDT with the biocarbonate deposition; the gradual increase of the particulate matter in the deposit is detrimental to the accumulation and enrichment of the ocps in the deposit. In this paper, the multi-cyclic aromatic hydrocarbons in the surface sediment samples in the culture area of the Ailin Bay were quantitatively analyzed. The ecological risk and the comprehensive ecological risk of the polycyclic aromatic hydrocarbons in the sediment were evaluated by RQ and SQG. The source of the polycyclic aromatic hydrocarbons and the correlation with the sediment-related parameters were preliminarily analyzed. and provides scientific basis for organic pollutant pollution control and environmental management and the like. The results showed that the content of all kinds of polycyclic aromatic hydrocarbons in the surface sediments of the Gulf of Linlin Bay was 71.03-148.64 ng 路 g ~ (-1), the average value was 107.87 ng 路 g ~ (-1), and the mean range of each PAHs was 0.50-18.49 ng 路 g ~ (-1). The average SQG quotient (mERM-Q) value obtained by the calculation of the risk quotient (RQERL) value of the multi-cyclic aromatic hydrocarbon and the value of the value (ERM) in the range of effect according to the effect range (ERM) is less than 0.1, the RQERL value is mostly less than 0.1, the data result shows that, The ecological risk and the biological toxicity of the toxic pollutants in the sediment of the culture area are not obvious at each point. The source of the polycyclic aromatic hydrocarbon in the bottom mud of the culture area in the Erlin Bay is mainly the combustion source of firewood, coal, or the mixture with the source of petroleum combustion, which may also be due to the human activity and the discharge of the oil in the transportation process of the HNA. The content of TOC, TOC, Ca and the particle size of the particulate matter are related to the accumulation and enrichment of polycyclic aromatic hydrocarbons, and there is a significant correlation between the similar molecular weight PAHs. The total amount and distribution of heavy metals in the sediment of the culture area were analyzed, and the enrichment status, the ecological risk, the biological toxicity risk, the human health risk and the possible sources of the heavy metals in the research area were evaluated. The results showed that the concentration of Ni, Pb, As and Zn in most of the sites was high, and it was a heavy element. The pollution of Ni in the cage and the oyster breeding site was serious. The SQGs were used to evaluate the results. As a result, the results showed that As, Pb and Ni exhibited higher ecological risk. The highest ecological risk of heavy metals in the sediment of the Bay of the northwest of the Yilin Bay is the highest ecological risk. The Hakanson index method is used to show that the Cd, As and Hg reach the risk of moderate to strong ecological harm, and the heavy metal in the bottom mud in the surrounding site of the flood island is at the risk of strong ecological harm; The method of risk assessment based on heavy metal form (RAC) was used to evaluate the risk of high ecological risk of Cd in the sediment of culture area, and the risk of medium ecological harm was mainly found in Ni. The method for evaluating the content of non-residual sulfide and organic matter (NNR-AVS)/? OC, the results show that the risk value of toxic heavy metals in all sampling point deposits is less than 150. m u.mol/ gOC, and that the sediment is not expected to be adversely affected; the results of the human health assessment (HQ) show that the HQ value is less than 1 and no potential health risk is exposed to the metal by ingestion, The primary source of the study was analyzed by the principal component analysis method. The results show that the combustion of the vessel gasoline and diesel oil in the study area is the main source of pollution.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X826;X55

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