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1.
Samples of atmospheric particulate matter obtained from representative areas of the city of Baghdad were collected on glass fiber filters using a high-volume sampler. Atomic absorption techniques were used to analyze the total suspended particulates (TSP) for the following trace metals; Fe, Cu, Zn, Pb, Mn, Cr, Cd, Co, and Hg. Sulfates were measured by turbidemetric method. Ion-selective electrodes was used for chloride analysis. It is concluded that the major components of TSP in the ambient air of Baghdad consist of mineral dust. Pb and Cd gave high enrichment factor values, which implies enrichment of these two metals from anthropogenic sources. High enrichment factors were also obtained for Zn and Cu. It is also concluded that in this arid area, the black smoke reflectance method is not suitable for measuring total suspended matter gravimetrically.  相似文献   

2.
江苏海港建设方兴未艾,赣榆港和大丰港发展速度尤为突出。分别选取赣榆港和大丰港海域的6个和8个沉积物调查站位,通过地统计分析探讨主要污染来源空间分布和来源组成特征,并对重金属污染现状进行评价。结果显示,赣榆港表层沉积物中Cd、As、Cu、Pb、Cr、Zn含量范围分别为0049 3~0098 7、73~178、199~412、132~192、275~542、438~812 mg/kg,空间分布上总体表现为近岸海域较离岸海域略高,沉积物重金属含量受到陆源影响,〖JP2〗其中重金属Zn与Cu存在相同或相似的来源,而As的来源与其他重金属差异均较大;大丰港表层沉积物中Cd、As、Cu、Pb、Cr、Zn含量范围分别为0037 8~0229 0、57~190、32~275、100~231、620~870、320~859 mg/kg,重金属空间上区域变异显著,除Cr外的重金属之间存在相同或相似来源。污染评价显示,赣榆港和大丰港整体污染程度总体较轻。港口建设初期的海洋沉积物调查与评价,不仅反映该海域初始的沉积环境状况,为沉积环境影响评价提供参考,还能为港口规模和产业选择提出限制条件  相似文献   

3.
滴水湖沉积物中重金属污染特征与评价   总被引:1,自引:0,他引:1  
分析滴水湖及其周边沉积物中Hg、As、Cu、Cd、Pb、Zn和Cr等7种重金属含量特征,并用地累积指数法、潜在生态风险指数法和主成分分析法对沉积物中的重金属污染状况进行了评价和分析。结果表明,滴水湖沉积物中As和Pb低于上海市潮滩背景值,Hg、Cd、Zn和Cr均高于潮滩背景值,50%样点的Cu高于潮滩背景值;地累积指数法评价结果表明滴水湖沉积物中Cr的平均污染水平为偏中污染,Hg、Cd和Zn为轻度污染,As、Cu和Pb为清洁水平;潜在生态风险指数法评价结果表明滴水湖沉积物重金属为中等生态风险,Hg和Cd是潜在生态风险的主要贡献元素;主成分分析结果表明,滴水湖沉积物中Hg、Cu、Cd、Pb、Zn和Cr主要来自于人为源,As主要来自底质滩涂  相似文献   

4.
The present geochemical analyses of Zn, Pb and Cd in eighteen subsurface sediment samples collected from two locations along the Jordan River show that Cd is anthropogenically enriched in these sediments. In the sediment column, the concentration of Zn, Pb and Cd decreases clearly with depth in the first location of the upper reach, due to the high rate of sedimentation in this location; whereas the enrichment of elements of the lower reach increases gradually towards the old sediments. The Anthropogenic factor of the studied metals lies in the sequence of Pb>Cd>Zn.  相似文献   

5.
长江口潮滩沉积物中活性重金属的空间分异及控制机制   总被引:1,自引:0,他引:1  
利用盐酸羟氨-25%醋酸溶液,提取了长江口潮滩沉积物中活性重金属含量。研究发现,长江口潮滩沉积物中活性重金属占总量的百分含量依次为Cu 26%,Pb 36%,Fe 7%,Mn 49%,Zn 32%,Cr 14%和Al 16%,沉积物基本未受到Cr污染,其余重金属污染程度处于中等偏下水平。除Zn、Cr外,其余活性重金属在夏季沉积物中的含量明显低于春季,其主要原因是夏季风暴潮将大量细颗粒泥沙及其富集的重金属带离潮滩进入了河口水体中。受点源污染排放及沉积物粒度影响,活性重金属在长江口南岸的浒浦、顾路和浦东机场出现峰值含量,且高潮滩含量明显高于中、低潮滩。在垂向上,重金属一般在沉积物表层或亚表层形成富集。在口门附近的滨岸潮滩沉积物中,Cu、Pb的空间分异主要受早期成岩作用的控制,在污染较为严重、水动力作用相对较弱的潮滩沉积物中,Cu、Pb的空间分异主要受沉积物中有机质含量变化的控制.  相似文献   

6.
鄱阳湖水土环境及其水生维管束植物重金属污染   总被引:24,自引:1,他引:23  
位于鄱阳湖流域乐安河中下游的德兴铜矿,是我国著名的大型铜业基地,是鄱阳湖流域重金属污染的主要来源之一。2003年7月至8月对鄱阳湖部分流域的水质、沉积物、底泥及水生维管束植物等样品的重金属污染进行了研究调查,采用原子吸收分光光度法分别对样品中的Cu、Zn、Pb、Cd等重金属含量进行了测定,并对测定结果进行了评价。研究结果表明,鄱阳湖流域水体中的重金属含量均达到地表水评价标准中的Ⅰ类标准,底泥、土壤等已受到了一定程度的重金属污染。而水生植物对重金属元素都具有不同程度的富集能力,植物对重金属的富集作用与土壤背景值有一定的相关性,土壤中重金属的背景值越高,植物对重金属的富集量也相应增加。  相似文献   

7.
Components and quantity of street dust are environmental pollution indicators especially in big cities. Street dust is generally composed of car exhaust gas originated particles and wind-transported particles. Heavy metals, which are found in street dust, such as Pb, Cu, Mn, Zn, Cd and Ni are significant for environmental pollution. According to the kind of vehicle in traffic, quantity and type of heavy metals vary in street dust. The use of leaded gasoline gives a boost to the importance of lead level especially in street dust even at the start of 21st century. These metals possess bioaccumulation property, and the possibility of the amount of these metals reaching a critical value and threatening human health increases the importance of this issue. In this study, street dusts have been collected from E-5 Highway from Topkapi to Avcilar regions that spans about 18 km in Istanbul, Turkey, and Pb, Cu, Mn, Zn, Cd and Ni concentrations have been detected in street dust. Twenty-two street dust samples were taken from a total of 22 different points at previously decided 14 main areas. Analyses were conducted using Leeds Public Analyst method. According to the results of this study, Pb, Cu and Zn concentrations in E-5 Highway between Topkapi and Avcilar region in Istanbul were higher than maximum concentration levels of these heavy metals in normal soil. This situation indicates that there is heavy metal pollution in the inspected area in E-5 Highway in Istanbul.  相似文献   

8.
长三角典型城郊农田土壤-浙贝母重金属迁移特征研究   总被引:1,自引:0,他引:1  
城郊生态系统中土壤重金属分布及其在土壤—植物系统的迁移和富集特征是城乡共生体土壤安全研究的热点问题。以典型经济作物浙贝母(Fritillaria thunbergii)为例,基于野外采样和实验分析,对长三角代表性城郊农田中土壤—植物系统重金属的分布、富集和迁移特征开展研究。结果表明:受人类活动的影响,城郊农田土壤中重金属除Cr外,Cu、Zn、As、Cd和Pb的平均含量超过土壤背景值,并且不同重金属在空间分布上表现较高的空间异质性。除Cd和Cr外,浙贝母植株不同部位重金属含量表现为叶、茎显著高于鳞茎,叶中重金属含量可达到鳞茎的5~10倍,表明叶比鳞茎更易富集重金属。重金属迁移系数分析表明,Cr、Cu、Zn、As、Cd和Pb主要富集在浙贝母植株的地上部分,且不同重金属在植株中的迁移和富集能力具有较大的差异。浙贝母地上部分对Cr、As和Pb的富集能力较低,对Cu、Zn和Cd的富集能力相对较强。相比而言,鳞茎对不同重金属的富集能力均较弱,综合污染评价也表明,浙贝母鳞茎中重金属含量并未超过污染标准。  相似文献   

9.
A field survey of higher terrestrial plants growing on Lanping lead-zinc mine, China were conducted to identify species accumulating exceptionally large concentrations of Pb, Cd, Cu and Zn of 20 samples of 17 plant species. Concentrations of Pb and Zn in soil and in plant were higher than that of Cu and Cd. Significant difference was observed among the average concentrations of four heavy metals in plants (except Cd and Cu) and in soil (except Pb and Zn) (P<0.05). For the enrichment coefficient of the four heavy metals in plant, the order of average was Pbtree>herbaceous, and herbaceous grew in soil with the highest concentrations of four heavy metals. In different areas, the concentrations of Pb, Cd, Cu and Zn in plants and soils and enrichment coefficient were different. Plants in Paomaping had more accumulating ability to Pb, Cd and Zn, and plants in Jinfeng River had more accumulating ability to Cu. Six plant species, i.e. S. cathayana, Lithocarpus dealbatus, L. plyneura, Fargesia dura, Arundinella yunnanensis and R. annae in Paomaping, had high accumulation capacity. R. annae in Paomaping had hyperaccumulating capacity to Pb, Cd and Zn, L. plyneura to Pb and Cd, and S. cathayana to Cd, respectively.  相似文献   

10.
Copper, zinc, lead and cadmium heavy metals were determined in sediments from the Kenyan Coast. Sediment samples were obtained from Makupa and Port Reitz Creek systems. The samples were digested using concentrated hydrochloric acid and the metal content determined using Atomic Absorption Spectrophotometer (AAS). The method of analysis was evaluated using Soil-7 certified reference material (International Atomic Energy Agency, IAEA). For comparison, sediment samples were also analysed using Energy Dispersive X-ray fluorescence technique and results obtained show good agreement. Higher metal concentrations were obtained in Makupa Creek sediments (Cu, 102+/-46.0; Zn, 1017+/-840; Pb, 103+/-35.8; Cd, 51.0+/-14.3) as compared to Port Reitz Creek system (Cu, 21.6+/-7.1; Zn, 57.1+/-17.9; Pb, 26.2+/-11.6; Cd, 1.38+/-0.7). There was significant (p=0.05) variation in the elemental concentrations between and within sites. Industrial activities and a nearby municipal dumpsite were associated with the higher elemental concentrations particularly in Makupa Creek.  相似文献   

11.
The relationship between Zn, Cu, Cd, Pb, and Ni concentrations in soft tissues of mussels and oysters and those in ambient sediments was examined. The study area was the coastal habitats of the northwestern Sea of Japan, which has a broad range of contamination due to urban sewage. Significant increases of all metals, except Ni, were observed in mussel Crenomytilus grayanus at concentrations of easily leachable metals in ambient sediments higher than 2, 100, and 800 microg/g for Cd, Cu, and Zn, respectively. Pb was accumulated by the mussels with no distinct threshold in Pb contamination of sediments. After 2 months, C. grayanus transplanted from a pristine to a contaminated locality increased in Pb up to 12%, and Cu up to 68% of concentrations of these metals in the contaminated local mussels, but Zn and Cd concentrations increased only in the excretory tissue, not in the somatic tissue, or in the soft tissue as a whole. Such regulation of metal accumulation puts limitations on the use of C. grayanus for monitoring of slightly and moderately contaminated localities. On the other hand, the oyster Crassostrea gigas showed definite accumulation of all metals, except Ni, at moderate contamination of ambient sediments. As contamination of sediments increased, increases of Pb, Zn and Cu concentrations in C. gigas slowed, possibly due to physiological control at very high metal concentrations in oyster soft tissue. Thus, the mussel C. grayanus should be used mainly for the monitoring of heavy contaminated localities, and the oyster C. gigas is more suitable as an indicator of low and moderate contamination.  相似文献   

12.
江阴市典型河流沉积物重金属污染和风险评价   总被引:1,自引:0,他引:1  
在摸清河流表层沉积物重金属(Cu、Zn、Pb、Cr、As)含量的基础上,利用综合污染指数和地累积指数评价其污染状况,计算潜在生态风险和人体健康风险。结果表明,江阴市河流沉积物已经受到重金属污染企业和城市径流双重影响,Cu、Zn、Pb峰值在汛期,As、Cr峰值在非汛期;污染负荷指数和地累积指数评价结果显示非汛期污染略轻,地累积指数法引入背景波动参数而使其评价结果较乐观。重金属潜在生态风险都为轻微风险级别;致癌风险处于10~(-3)数量级,非致癌风险数量级为10~(-7),致癌风险为人体健康风险主要承担者。潜在生态风险汛期高,人体健康风险非汛期高,这可能是重金属元素对致癌风险以及生态风险的贡献不同所致。  相似文献   

13.
Temporal changes in the amounts of trace elements (As, Co, Cu, Mn, Ni, Pb, and Zn) and their correlations with temporal changes in charcoal abundance in age-dated sediments collected from Lake Thompson in Patagonia, Chile, attest to the substantial pyrogenic remobilization of contaminants that occurred in Patagonia during the mid-1900s. This remobilization was concurrent with the extensive slash and burn period in the region during that period. The changes in concentrations of Co, Cu, and Ni in relation to charcoal abundance in the lacustrine sediments over time were small compared to those of As, Mn, Pb, and Zn. However, the relatively low enrichment factors of all those trace elements, normalized to Fe, indicate that they were predominantly derived from local, natural sources impacted by fires rather than industrial sources. The primarily local source of Pb in the sediments was corroborated by the temporal consistency of its isotopic ratios (206Pb/207Pb:208Pb/206Pb), which were similar to previously reported values for natural lead in Central and Southern Chile. However, the pyrogenic remobilization of both natural and industrial trace elements by forest fires in Chile and elsewhere is expected to rise as a consequence of climate change, which is projected to increase both the frequency and intensity of forest fires on a global scale.  相似文献   

14.
In this study, metals (Be, Cr, Mn, Fe, Ni, Cu, Zn, Ag, Cd, Pb and Hg) in the fine-grained fraction (<63 microm) from 12 sites at different locations in northern San Francisco Bay over a year period from March 2000 to March 2001 were analyzed after acid extraction. The results showed that metal concentrations in the sediments varied from site to site, whereas some of them were found elevated with respect to the sediment of Tomales Bay, CA, which has little contamination history, indicating an enrichment of the metals in the sediment samples analyzed. Sediment toxicity and bioaccumulation evaluation by a clam species, Macoma nasuta, exposed to the sediment samples collected from the six sampling sites was carried out. The results showed that the sediment samples tested significantly reduced clam survival. Toxicity of the sediments to the clam was, in part, related to elevated metal concentrations in the sediments. In order to examine geochemistry of the metals and to understand potential correlations between metal concentrations and geochemical matrix elements of the sediments, bioavailability and toxicity of the metals, detailed analysis of metal concentrations associated with total organic carbon and the Fe-oxy-hydroxides in the sediment samples was performed. The analysis showed that sediment geochemistry appeared to influence metal bioavailability and may have important impacts on the toxicity of these metals to the clam.  相似文献   

15.
The Pumicestone region is a unique catchment in northern Moreton Bay, southeast Queensland. The region supports a wide range of land-use activities as well as attractions such as nature conservation areas. One environmental aspect that has not previously been addressed in this area is the occurrence of minor and trace metals in estuarine sediments associated with the main estuaries of the region. The trace metals included in this investigation are: vanadium, chromium, molybdenum, cobalt, nickel, copper, zinc, cadmium, lead and arsenic. To determine and evaluate the occurrence and distribution of metals in the area, several components have been analysed: bedrock material, pre-industrial settings, recent estuarine sediments, soils of estuarine origin and mangrove pneumatophores. The 40 sites chosen for sediment and soil samples cover a variety of estuarine settings and represent a range of natural conditions in terms of channel and bank morphology, tidal energy, vegetation cover, relationship to bedrock, water salinity and land disturbance. The chemical, mineralogical and statistical analyses employed in this study enabled (a) establishment of background values for the area, (b) determination of relationships between metals and (c) identification of sites with anomalous metal concentrations. All the metals found in the sediments of the area are sourced from the geological bedrock. The dominant trace elements identified in sediments are Zn, V and Cr. The remaining metals are highly variable spatially. All trace metals are controlled by the presence of Fe and Mn oxides, and by the grainsize of the sediment. Typically, fine-grained Fe-rich materials tend to adsorb more trace metals than sandy sediments. In soils that have developed from estuarine muds, some metals such as Cr, Mo, Pb and As tend to be in larger quantities than in the estuarine counterparts. Some of the elements, which occur in significant amounts in the sediment, have been detected in mangrove tissue (Avicenniamarina) such as V, Cr, Zn, Fe and Mn. Of particular note is Cu, which is present in mangrove tissue in quantities many times exceeding the sediment concentration. The comparative analysis of pre-industrial settings and recent sediments and soils highlighted some areas of metal enrichment such as acid-affected sites where oxidation of pyrite has mobilised metals from sediments; these metals are then redistributed in Fe-rich surficial layers. Disturbed banks within the estuaries are also likely to have low levels of metal enrichment due to boating activities.  相似文献   

16.
盲数优化地积累模型是基于最大隶属度原则和隶属度加权相结合的一种不确定性评价方法。鉴于污染评价系统多种不确定信息共存的特点,将盲数优化地积累模型应用于长江中下游不同类型湖泊沉积物中重金属污染程度评价中。根据计算出的可能值区间及可信度看空间分布的均匀性,以及评价等级的可信度水平,辨识污染程度和等级,减小局部污染对区域整体污染程度的影响。结果表明:象湖、鄱阳湖、洞庭湖3个湖泊表层沉积物中的重金属的空间分布都不均匀,象湖表层沉积物中重金属的污染情况为:PbCuZn,其中Pb为中度污染,Cu为轻度污染,Zn为清洁;鄱阳湖沉积物中重金属污染评价结果为Cu﹥Pb﹥Zn,其中Cu为中度污染,Pb为偏中度污染,Zn为偏重污染;洞庭湖沉积物中重金属污染评价结果为Cu≈Pb≈Zn,且均为轻度污染。盲数优化地积累模型方法可行,与定性评价结果基本一致,但在对污染等级判定上更真实可靠。弥补了传统确定性方法的不足,更真实、更客观地表征了评价区域沉积物重金属的富集污染程度。  相似文献   

17.
对丹江口水库上游汉江支流及库湾沉积物中6种重金属元素的污染特征进行分析,采用效应阈值标准(NYSDEC)和Lars Hkanson潜在生态风险指数评价重金属的污染程度和环境风险。研究表明,库湾沉积物与支流沉积物中Ni、Pb含量较为接近;库湾沉积物中Cd、Cr、Cu、Zn含量分别高达186、2712、9991、4783 mg/kg,均超过支流沉积物中相应重金属含量2倍以上。各采样点表层(0~10 cm)沉积物中Pb含量均低于LEL值(最低效应阈值),Cd、Ni含量均介于LEL值和SEL值(最高效应阈值)之间,而Cr、Cu、Zn含量均有超过SEL值的现象发生。考察沉积物重金属的富集程度发现各采样点表层沉积物中Ni和Pb均未发生富集,而Cd、Cr、Cu和Zn均存在不同程度的富集,其平均富集系数分别为712、180、163和284。根据重金属含量的相关性可知Ni和Pb主要来自于天然地球化学来源,而Cd、Cr、Cu和Zn则主要受人为源影响。以丹江口库区土壤(黄棕壤)中重金属背景值为参比,发现表层沉积物总体处于高生态风险,且以Cd生态风险为主;参与评价的5种重金属潜在生态风险程度顺序为Cd>Cu>Cr>Zn>Pb  相似文献   

18.
根据长江口洋山海域表层沉积物监测资料,利用变异系数法和富积系数法,对表层沉积物中重金属的空间波动程度及富积程度进行了分析,并采用Hakanson潜在生态危害指数法对其潜在生态危害程度进行了评价。结果表明:在表层沉积物所监测的重金属中,Pb元素的空间波动程度最高,其它重金属元素的空间波动程度较低,各重金属空间波动程度的顺序依次为Pb>Cd>Hg>Cu>Cr>As>Zn;沉积物中Cu元素的富积程度最高,Pb元素次之,其它重金属元素的富积程度较低,各重金属富积程度的顺序依次为Cu>Pb>Zn>As>Cr>Cd>Hg。潜在生态危害评价结果显示:洋山海域表层沉积物中的重金属对海洋生态系统的潜在生态危害较轻微,均属于轻微潜在生态危害程度,其轻微潜在生态危害程度顺序为Cu>As>Hg>Pb>Cd>Cr>Zn。  相似文献   

19.
Trace metals (Fe, Mn, Cu, Co, Ni. Pb, Cd and Cr) analyses in particulate matter and sediments were carried out at 16 different stations in the Godavari mangrove ecosystem covering the three regions viz., Kakinada (KKD) bay, Goutami-Godavari estuary (GGE) and Coringa and Gaderu mangrove environments (CGME). Higher concentrations of trace metals in particulate matter and in sediments were noticed in the mangrove environment compared to the KKD bay and GGE region. The significant correlations observed between several couples of metals in different regions as well as between numbers of heavy metals (Fe, Mn, Zn) with Total Suspended Matter (TSM) in particulate organic matter could be an indication of the role of the complexation with organic matter in the distribution pattern of these metals. Further significant correlations between organic carbon (OC) and Cr, Co, Pb, Cu and Mn in sediments of all the three regions indicate that organic matter acts as a metal carrier. The values of Pollution Load Index (PLI) were low and varied between 0.34 and 0.68 in KKD bay, 0.47 and 0.49 in GGE and, from 0.62 to 1.03 in CGME area, which indicate that the estuarine ecosystem is not of pollution concern under the present scenario.  相似文献   

20.
The concentration of Fe, Mn, Zn, Cu, Pb, Ni, Cr, Cd, and Ag were determined in the brown alga Fucus vesiculosus and intertidal surface sediments from coastal locations of northeast England. Levels of heavy metals similar to those of polluted areas of the British coastline were detected. There is evidence of contamination (especially with Zn and Pb) in sediments from sites affected by colliery spoil and from the Wear estuary. The pelitic fraction ( < 63 microm) is usually more enriched in heavy metals, but it represents a very small percentage of the bulk samples. The fine-grained sand is a very important repository of contaminants especially where particles of colliery spoil, secondary mineral, and amorphous phases are present. Aqua regia-extracted Zn, Cu, and Pb in sediments are significantly correlated with those in seaweed. Despite the closure of all base metal and coal mines, and the cessation of many industrial activities in the region, sediments and brown algae are contaminated with heavy metals. The control site (Holy Island) and the Tees estuary appear to be the least affected.  相似文献   

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