淮河中游（安徽段）微量元素的环境地球化学研究

发布时间：2018-01-01 18:09

  本文关键词：淮河中游（安徽段）微量元素的环境地球化学研究　出处：《中国科学技术大学》2017年博士论文　论文类型：学位论文

  更多相关文章： 淮河 水体 沉积物 微量元素 形态 铅同位素

【摘要】：本文以淮河中游(安徽段)寿县正阳关至蚌埠闸区段系统采集的211个水样品,54个表层沉积物样品,及两个沉积柱样品作为研究对象,综合利用混合酸消解,BCR连续形态提取及铅同位素定年等实验分析方法,应用电感耦合等离子体原子发射光谱和质谱等测定和分析了样品中微量元素(Cu,Pb,Zn,Ni,Co,Cr,Cd,As,Mn,Fe,Al,B,Ba,Mg)的总量,形态及铅稳定同位素(204Pb,206Pb,207Pb,208Pb),并结合多种污染和风险评价手段,及多元统计分析(相关性分析,主成分分析及聚类分析)等数据处理方法对淮河水体及沉积物中微量元素的分布规律与富集特征,赋存状态,潜在风险及来源进行了分析研究。本研究的主要结果如下:(1)系统分析了淮河水体溶解态微量元素的时空分布特征(垂向分布和水平分布),水质污染状况及微量元素的健康风险水平,研究发现Cu,Pb,Zn,Ni,Cr,Cd,Co,Mn污染主要发生在凤台和淮南地区,其中,Pb,Zn,Cd是淮河水体的主要污染元素,并且微量元素的健康风险评价揭示了元素Co,Cd,Pb会对人体健康产生潜在非致癌性风险;(2)基于表层沉积物理化性质,微量元素总量和赋存形态,结合多种污染和风险评价方法(地积累指数,富集因子,污染负荷指数及潜在生态风险指数)揭示了研究区沉积物中微量元素的分布规律,污染程度及风险水平,研究结果表明沉积物中微量元素的污染程度为AsZn,CdPb,MnCu,CrFe,NiA1;其中Cd,As及Pb对生态环境质量具有较高的潜在风险;Mn的生物可利用性最高,其次为:AsZnCuPbNiFeCr;沉积物中As和Pb的主要形态为铁锰氧化物结合态,Zn,Cu,Fe,Ni,Cr主要以残渣态存在;(3)基于相关性分析,主成分分析和聚类分析探讨了淮河水体及沉积物中微量元素的可能来源,研究发现淮河中游(安徽段)微量元素的来源复杂多样。B,Ba,Mg,A1主要为自然来源,Mn,Cu,Co,Ni,Cr,Fe受自然源及人为源的共同影响,而Cd,As,Pb,Zn主要来自人为源,通过分析发现水体及沉积物中微量元素的主要人为源有生活污水的排放,采矿活动,煤炭燃烧、电厂燃煤飞灰及汽车尾气的大气沉降,农药的使用,以及淮河支流(东淝河,茨淮新河及涡河)污水的汇入等;(4)利用210Pb同位素定年技术和Pb稳定同位素(204Pb,206Pb,207Pb,208Pb)示踪方法揭示了淮河沉积物中微量元素在1959至2014年间的分布规律,富集特征,赋存形态及来源,研究发现微量元素的历史分布特征与人类活动紧密相关,微量元素含量(Fe,Mn,Zn,Co,Cu.Ni,Pb,Cr,Cd,As)从1990s(1991-2014年)呈现逐渐增加的趋势,并且在1991,1994-1998及2004年出现微量元素峰值,表明微量元素分布可能受到了该地区的工农业发展及20世纪90年代及2004年水污染事故的影响。Pb稳定同位素示踪方法揭示了沉积物中Pb的来源变化,从1970年代中期以来,Pb主要来源于煤矿开采,煤炭燃烧,垃圾燃烧及汽车尾气(无铅汽油),1970年代中期以前,Pb含量可能受到大跃进时期冶金活动的影响。
[Abstract]:In this paper, the middle reaches of the Huaihe River (Anhui section) 211 water samples collected from Shouxian County Zhengyangguan to Bengbu gate section of the system, 54 surface sediment samples, and two sediment samples as the research object, the comprehensive utilization of mixed acid digestion, BCR continuous form extraction and lead isotopic dating and experimental analysis, determination and analysis of trace elements in samples by inductively coupled plasma atomic emission spectrometry and mass spectrometry (Cu, Pb, Zn, Ni, Co, Cr, Cd, As, Mn, Fe, Al, B, Ba, Mg) the amount, morphology and stable lead isotopes (204Pb, 206Pb, 207Pb, 208Pb), combined with a variety of pollution and the risk evaluation method, analysis and multivariate statistics (correlation analysis, principal component analysis and cluster analysis) data processing method of the distribution of trace elements in water and sediment of Huaihe and enrichment characteristics, occurrence, and potential risk sources are analyzed. The main results of this study Are as follows: (1) analyzed the temporal and spatial distribution of trace elements in Huaihe water dissolved (vertical distribution and horizontal distribution), the level of health risk of water pollution and trace elements. The study found that Cu, Pb, Zn, Ni, Cr, Cd, Co, Mn pollution mainly occurred in Fengtai and Huainan. Among them, Pb, Zn, Cd is the main pollution elements in Huaihe water, and health risk assessment of trace elements reveals the elements of Co, Cd, Pb have the potential non carcinogenic risk to human health; (2) the surface physical and chemical properties of the sediments based on the total amount of trace elements and speciation, combined with a variety of pollution and risk assessment methods (accumulation index, enrichment factor, pollution load index and the potential ecological risk index) reveals the distribution of trace elements in sediments in the study area, the pollution degree and the level of risk, the results show that the deposition of trace elements pollution in AsZn, CdPb, Mn Cu, CrFe, NiA1; Cd, As and Pb have high potential risk of ecological environment quality; Mn bioavailability is the highest, followed by: AsZnCuPbNiFeCr; main form of As and Pb in the sediments is bound to Fe Mn oxides, Zn, Cu, Fe, Ni, Cr are mainly in residual form; (3) based on the correlation analysis, principal component analysis and cluster analysis to explore the possible sources of trace elements in water and sediment of Huaihe, the study found that the middle reaches of the Huaihe River (Anhui section) sources of trace elements of the diversity of.B, Ba, Mg, A1 are mainly natural sources, Mn, Cu, Co, Ni, Cr, Fe from natural sources and anthropogenic influence, while Cd, As, Pb, Zn mainly from anthropogenic sources, through the analysis found that the major anthropogenic source of trace elements in water and sediment of sewage discharge, mining activities, coal combustion, coal-fired power plant fly ash deposition and automobile exhaust air, the use of pesticides, and Huaihe branch Flow (Dongfeihe River, cihuai New River River sewage inflow and vortex); (4) Pb isotope dating technique and using 210Pb (204Pb, 206Pb, 207Pb isotope tracer method, 208Pb) revealed in the sediments of Huaihe trace elements distribution in 1959 to 2014 years, the enrichment characteristics and morphology the occurrence of trace elements in historical sources, distribution is closely related to human activities is found, the contents of trace elements (Fe, Mn, Zn, Co, Cu.Ni, Pb, Cr, Cd, As) from 1990s (1991-2014) increases gradually, and the trace element peak in 19911994-1998 and 2004, suggesting that the trace elements distribution may be in the area of industrial and agricultural development and water pollution accident in 1990s and 2004 of.Pb stable isotope tracer method reveals the sources of variation of Pb in sediments from the middle of 1970s, since the Pb comes mainly from coal mining, coal combustion. The combustion and vehicle exhaust (unleaded gasoline), before mid 1970s, the content of Pb may be affected by the metallurgical activities during the great leap forward.

【学位授予单位】：中国科学技术大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：X142
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本文编号：1365611