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1.
On their way from the Rhine estuary into the North Sea and Dutch Wadden Sea, Rhine sediments “lose” large portions of their
original heavy metal concentrations. Until now these losses were explained by a mobilization process, solubilization — the
decomposition products of organic matter form soluble organometallic complexes with the metals of the sediment.
Our investigations of the sediments of the Elbe clearly indicate that a mixing process, whereby highly polluted Elbe sediments
mix with relatively non-polluted North Sea sediments, rather than solubilization, is the cause of the dilution of heavy metals
in the sediments of the Elbe estuary. Because of the similarity of the Elbe data with those from the Rhine River, we propose
that a mixing process is also effective in the Rhine estuary and adjacent North Sea areas.
The mechanism by which heavy metals are “diluted” is important to the marine ecosystem. In the mixing process proposed in
this paper, the heavy metals fixed to the suspected material are trapped in bottom sediments of the marine environment, whereas
solubilization would increase the concentration of heavy metals in the sea water and thus they would be more available for
uptake by aquatic organisms. 相似文献
2.
西安市可吸入颗粒物中重金属分布规律 总被引：2，自引：0，他引：2
以西安市为例测定了大气可吸入颗粒物中铅（Pb）、镉（Cd）、铜（Cu）、铁（Fe）重金属含量。结果表明铁浓度明显要高于其它三种金属元素，而且工业区、商业区、文教区大气可吸入颗粒物中重金属浓度均显著高于相应对照区。其主要原因是西安市还是一个典型的燃煤城市，煤中矿物质燃烧释放出来的含有金属气体影响到了西安市的大气环境质量，得出了西安市大气中重金属元素的分布规律，结合实际初步分析了其影响因素、污染来源和发展趋势，为以后西安市的发展提供了一个参考。另外，西安市作为大城市，汽车消费的普及，交通量的增大是城市铅污染加重的主要原因，针对这些污染源提出了解决此问题的建议。 相似文献
3.
The methane concentration in the atmosphere andsurface water was surveyed along 58° N acrossthe North Sea. In addition, the vertical methanedistribution in the water column was determined at sixstations along the transect. The methane contents ofthe surface water as well as in the water column wereextremely inhomogeneous. Input by freshwater fromriver discharge and injection of methane from thesediment were both observed. The survey continued fromthe western side of the North Sea to the Elbe Riverestuary. The Elbe River appears to have low methaneconcentrations compared to other European rivers, itsaverage input into the North Sea is estimated to be70 nmol s-1 of methane. Near 58° N,1°40' E, an abandoned drill site releases about 25 % ofthe North Sea's emission of methane to the atmosphere.The advective methane transport induced by watercirculation was assessed for May 16, 1994, using a 3-DNorth Sea circulation model. For the period of thissurvey, the North Sea's source strength foratmospheric methane is estimated using in situwind velocities. In comparison to the advectivetransport by the water circulation, the gas flux tothe atmosphere appears to be the dominant sink ofNorth Sea methane. This flux is estimated to bebetween 1500 · 106 mol a-1 and 3100 ·106mol a-1, depending on the relationbetween wind speed and gas transfer velocity. 相似文献
4.
《Applied Geochemistry》2002,17(4):337-352
Organic C burial rates and C–S relationships were investigated in the Holocene sediment sequences of 3 shallow polymictic coastal lagoons in the southern Baltic Sea to better understand the biogeochemical cycling of C and S in these environmental systems. The results show that these lagoons may have a considerable influence on the environmental status of the southern Baltic Sea area in having the potential to act as a temporary sink or source for heavy metals. High organic C accumulation rates (Corg-AR) can be observed in the sediments due to a high organic matter supply from land and a high productivity of the water bodies as a result of eutrophication. However, organic C burial does not increase as a result of increasing sediment accumulation rates (SAR). Even when high sedimentation rates do occur, there appears to be a thorough recycling and resuspension of the sediment enhancing the biological decay of organic matter before burial or the removal of organic matter from the system by transport. That is why high SAR in the coastal lagoons do not enhance pyrite formation, and thereby permanent fixing of heavy metals in the sediments, to the extent that could be expected from their magnitude. Initially there is a high potential for a temporary binding of heavy metals, but the latter are likely to be subject to mobilization and redistribution within the sediments and the water column. The patterns of burial of organic and mineral matter are different from those observed in the present-day Baltic Proper, implying possible important links in deposition between the central and coastal areas of the Baltic Sea and implications for C cycling in the ecosystem of the Baltic Sea. 相似文献
5.
Bethan J. Davies David H. Roberts David R. Bridgland Colm Ó Cofaigh James B. Riding 《第四纪科学杂志》2011,26(1):59-75
As the majority of the data on Quaternary sediments from the North Sea Basin are seismostratigraphical, we analysed the Elsterian Swarte Bank Formation, the Late Saalian Fisher Formation and the Late Weichselian (Dimlington Stadial) Bolders Bank Formation in order to determine genesis and provenance. The Swarte Bank Formation is a subglacial till containing palynomorphs from the Moray Forth and the northeastern North Sea, and metamorphic heavy minerals from the Scottish Highlands. The Fisher Formation was sampled from the northern and central North Sea. In the north, it is interpreted as a subglacial till, with glaciomarine sediments cropping out further south. These sediments exhibit a provenance signature consistent with the Midland Valley of Scotland, the Eocene of the North Sea Basin, the Grampian Highlands and northeast Scotland. The Bolders Bank Formation is a subglacial till containing palynomorphs from the Midland Valley of Scotland, northern Britain, and a metamorphic heavy‐mineral suite indicative of the Grampian Highlands, Southern Uplands and northeast Scotland. These data demonstrate that there was repeated glaciation of the North Sea Basin during the Middle and Late Pleistocene, with ice sheets originating in northern Scotland. There was no evidence for a Scandinavian ice sheet in the western North Sea basin. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
6.
本文目的在于说明有限区域内潮坪小环境沉积物的矿物学和地球化学特点及沉积过程的改造作用。沉积物样品取自汪额诺格岛与联邦德国的德国湾南岸之间的障壁潮坪。粒度分析表明,障壁潮坪由大体平行于大陆的泥坪、混合坪到砂坪三个带组成。粘土矿物以伊利石为主,其次为蒙脱石、高岭石和绿泥石,与北海粘土矿物组合一致。粘土矿物组成和重金属Fe、Mn、Cu、Pb、Zn含量在潮坪不同部位相差无几,说明沉积物受到潮汐水流反覆侵蚀和再沉积作用的混合作用。近潮口附近有机碳含量增高是潮汐水流从北海通过进潮口携入有机物的结果。 相似文献
7.
潮滩沉积物重金属累积特征研究进展 总被引：21，自引：1，他引：21
在分析总结国内外潮滩重金属研究现状和成果的基础上，指出潮滩重金属来源的定量分析尚很不完整；沉积物的物质组成、粒径、水动力作用、潮滩生物、河流输入量、人类活动等都对重金属在潮滩的分布有着重要影响。在垂岸方向，重金属从高潮滩到低潮滩含量逐渐降低，反应了水动力以及粒径对潮滩重金属的分布的控制；沿岸方向，淤涨岸段，重金属含量低，排污口严重影响着重金属的沿程分布，重金属含量随离排污口的距离增大而呈指数减少；垂向方向，在许多地方重金属分布与人类活动、经济发展状况相吻合。生物活动使潮滩重金属的累计特征变得复杂，改变了潮滩局部的微环境。与国内外河口重金属研究相比，潮滩重金属的研究远远不足。沉积物中重金属常用研究方法，如Tes sier地球化学相连续提取法、Meso cosm模型，以及数值和现场模拟的方法的应用，对潮滩重金属的研究将有很大帮助。在潮滩重金属的污染评价中，生物标准较其它标准更为适合。 相似文献
8.
空气滤膜吸附采集甘肃某农场大气粉尘样品,采用盐酸—硝酸—氢氟酸—高氯酸溶解,电感耦合等离子体质谱法（ICP-MS）同时测定溶液中铬、铜、砷、镉、铅等重金属元素含量,分析农田环境大气颗粒中的重金属元素对农作物的影响,同时验证不同仪器工作参数对测定结果的影响。实验表明：在选定的实验条件下,分析元素的检出限低,准确性和精密度... 相似文献
9.
E. Dimitrakakis J. Hahladakis E. Gidarakos 《International Journal of Environmental Science and Technology》2014,11(5):1421-1432
In the “Sea Diamond” shipwreck, it is estimated that almost 1.7 tons of batteries/accumulators and approximately 150 cathode ray tube technology televisions have gone to the bottom of the sea. Under these circumstances, all the aforementioned materials will eventually undergo severe accelerated corrosion. Consequently, a variety of heavy metals will either be released in seawater or precipitate in the form of salts resulting in contamination of the sea sediments. According to the ship data, and the aforementioned quantities of batteries and televisions, it is estimated that approximately 75–80 g of mercury, 630–1,050 g of cadmium and 1.14–1.26 tons of lead exist in the wreck only due to the electrical and electronic equipment present in the ship, not to mention the significant amount of heavy metals such as copper, nickel, ferrous and chromium that exist in the hulk. Four series of seawater sampling (n = 85) were conducted in different stations surrounding the wreck area in order to assess the overall impact from the release of heavy metals in the surrounding aquatic environment. The analysis indicated that there were stations where lead, zinc and cadmium were present in concentrations higher than the permissible limits set by the Unites States Environmental Protection Agency for seawater. Furthermore, the analysis of three series of sediment sampling (n = 31) from the wreck area showed elevated but expected concentration values for ferrous and manganese, considering the geological background of the area and contamination with lead, copper and cadmium. 相似文献
10.
Three soil profiles taken from the Hartwood Research Station in Central Scotland have been analyzed using chemical digestion and extraction techniques to investigate the chemical association of heavy metals deposited from the atmosphere. Total digestion, EDTA extraction and the BCR (Bureau Communitaire de Reference) sequential extraction procedure were used. In addition, lead isotope ratios in the whole soils and in the fractions from the sequential extraction procedure were measured using thermal ionisation mass spectrometry. All the digestion and extraction procedures gave clear indication of enhanced concentrations of heavy metals in surface soils, in particular for lead and zinc. Whereas total digestion gave a good indication of the heavy metal status of the soils, the extraction procedures were necessary to provide information on chemical association of the metals with soil components, information needed to understand the soil processes involved in mobilization of metals. Lead isotope analysis of the whole soils revealed a consistent picture of lower 206Pb/207Pb ratios in surface soils (1.140-1.147) than in soils at 20-30 cm depth (1.182-1.190). The steady progression from the lower to higher ratios down the profile was clear indication that anthropogenic lead had penetrated to some degree into the deeper soils. The combination of sequential extraction and lead isotope analysis proved to be a powerful approach to studying this effect in more detail and showed that the fractions extractable from 20 to 30 cm soils contained lead with much lower 206Pb/207Pb ratios (1.174-1.178) than the residual fraction (1.196-1.200). As the extractable fractions contained ≥85% of the lead in the soil, a substantial portion of lead at 20-30 cm depth was of anthropogenic origin. The 206Pb/207Pb ratios of 1.174-1.178 found in the extractable fractions suggested that the mobile component of the anthropogenic lead was that deposited before the introduction of leaded petrol. 相似文献
11.
《Chemical Geology》2002,182(2-4):377-394
Bulk heavy metal (Fe, Mn, Zn, Cu, Pb, Cd), Al, organic carbon and carbonate concentrations, grain sizes, and δC13 of the organic carbon distributions were studied in sediments collected throughout the East China Sea continental shelf and the Yangtze River Delta. The results demonstrated that terrigenous sediments from the Yangtze River is a dominating factor controlling the spatial variations of heavy metals and organic carbon concentrations on the East China Sea continental shelf. In addition, grain size and recent anthropogenic influences are also major factors modifying the spatial and vertical variations of heavy metals.Large spatial variations with a band type distribution of heavy metals, grain size, organic carbon and carbonate were observed. Higher concentrations of heavy metal and light δC13 of the organic carbon were found primarily in the Deltaic and inner shelf sediments. The band type distribution generally followed the coastline with little variations in the north–south direction. Away from the Delta and inner shelf (west–east direction), most heavy metal concentrations decreased rapidly with the exception of Cd where high concentrations of Cd were also found in the carbonate-rich shelf break sediments. Coarse-grained relict sediments and biogenic carbonate are two primary diluting agents for the fine-grained aluminosilicate sediments from the Yangtze River with high concentrations of heavy metals.Unusually high concentrations of Cu, Pb, and Cd showed both spatially and vertically that more pollution prevention measures are needed in the Yangtze River drainage basin in order to prevent further heavy metal pollution of the East China Sea inner continental shelf. 相似文献
12.
A. Das K V. S. S. Krishna R. Kumar M. C. Saha S. Sengupta J. G. Ghosh 《International Journal of Environmental Science and Technology》2018,15(1):159-172
Street dust from 29 locations, in some of the busiest parts of north and south Kolkata, was analysed for heavy metal composition. The decreasing order of average metal concentrations (mg kg?1) found was Mn (390) > Pb (380) > Zn (300) > As (96) > Cu (61) > Cr (40) > Co (13) > Ag (2.1). The heavy metal composition of the Kolkata dust was compared with reported data for other cities. Enrichment factors of Pb and As were high. Multivariate statistical analysis of the heavy metals and analysis of lead isotopic ratios of the dust revealed a predominant anthropogenic influence in the contamination. The range of lead isotopic ratios found in the dust was between 0.8789 and 0.8998 with a mean Pb concentration of 383 mg kg?1. The three Pb isotope plots of street dust, diesel and rainwater clustered linearly, while coal did not fit into this trend. The highest 207/206 lead isotopic ratio obtained was from diesel with a mean value of 0.9015, followed by the rainwater sample. The application of the binary mixing model showed that about 66.86% of lead contamination in the street dust was sourced from the atmosphere. The two components extracted by the principal component analysis explained 64.34% of the total variance. Vehicular and industrial emissions appeared to be an important contributor to the accumulation of heavy metals in the dust. The health risk assessment study of the dust indicated carcinogenic risk associated with As and Cr. 相似文献
13.
浙东沿海某地区大气干湿沉降对土壤重金属
元素含量的影响 总被引：7，自引：0，他引：7
基于对浙东沿海某典型固废拆解区重金属元素大气干湿沉降特征的研究,探讨了重金属元素干湿沉降输入对土壤环境的影响。结果表明,研究区露天焚烧等不规范的固废拆解行为造成大气质量恶化,对土地质量造成严重的负面影响。区内干、湿沉降中Cd、Cu、Pb、Zn、Ni等重金属元素的含量均远高于浙江省干、湿沉降平均值和其它相关标准值,并且其年沉降通量在省内居高,尤其是Cu、Zn两种元素每年每平方百米沉降通量分别达7108g、11420g。研究显示,大气沉降能大大增加研究区土壤重金属元素的含量水平,Cu、Zn、Cd、Pb平均年增加量分别达3426ng/g、5819ng/g、6.50ng/g、582ng/g,并且年增加率较大,Pb、Cu、Zn等重金属元素的年增加率达0.5%以上。 相似文献
14.
Partitioning of heavy metals in surface Black Sea sediments 总被引：1，自引：0，他引：1
Bulk heavy metal (Fe, Mn, Co, Cr, Ni, Cu, Zn and Pb) distributions and their chemical partitioning, together with TOC and carbonate data, were studied in oxic to anoxic surface sediments (0–2 cm) obtained at 18 stations throughout the Black Sea. TOC and carbonate contents, and available hydrographic data, indicate biogenic organic matter produced in shallower waters is transported and buried in the deeper waters of the Black Sea. Bulk metal concentrations measured in the sediments can be related to their geochemical cycles and the geology of the surrounding Black Sea region. Somewhat high Cr and Ni contents in the sediments are interpreted to reflect, in part, the weathering of basic-ultrabasic rocks on the Turkish mainland. Maximum carbonate-free levels of Mn (4347 ppm), Ni (355 ppm) and Co (64 ppm) obtained for sediment from the shallow-water station (102 m) probably result from redox cycling at the socalled ‘Mn pump zone’ where scavenging-precipitation processes of Mn prevail. Chemical partitioning of the heavy metals revealed that Cu, Cr and Fe seem to be significantly bound to the detrital phases whereas carbonate phases tend to hold considerable amounts of Mn and Pb. The sequential extraction procedures used in this study also show that the metals Fe, Co, Ni, Cu, Zn and Pb associated with the ‘oxidizable phases’ are in far greater concentrations than the occurrences of these metals with detrital and carbonate phases. These results are in good agreement with the recent studies on suspended matter and thermodynamic calculations which have revealed that organic compounds and sulfides are the major metal carriers in the anoxic Black Sea basin, whereas Fe-Mn oxyhydroxides can also be important phases of other metals, especially at oxic sites. This study shows that, if used with a suitable combination of the various sequential extraction techniques, metal partitioning can provide important information on the varying geological sources and modes of occurrence and distribution of heavy metals in sediments, as well as, on the physical and chemical conditions prevailing in an anoxic marine environment. 相似文献
15.
铅锌矿区地表环境中重金属元素的时空动态变化及生物有效性探讨 总被引：5，自引：0，他引：5
综述了近十年来国内外有关铅锌矿区重金属污染的一些研究进展。近十年来,国内外对铅锌矿山开发引起的重金属在土壤、植物、水和大气系统中的分布、形态、累积、迁移及转化机理等进行了广泛深入的研究,本文着重总结和探讨了铅锌矿区重金属的时空分布特征、生物有效性及其影响因素和机制等方面,以期能对这些方面有一个较为系统深入的理解并提出一些建设性意见。 相似文献
16.
基于重金属的区域健康风险评价——以成都经济区为例 总被引：10，自引：3，他引：7
开展重金属的区域健康风险评价,对于探讨重金属的风险及为区域的生态地球化学预测预警服务有重要的意义。以成都经济区植物和大气为研究对象,应用国外的风险评价理论对As、Cd、Hg和Pb 4种重金属进行了健康风险评价,探讨了区域风险评价的填图思路。对于非致癌效应,计算通过食物摄入和空气吸入2种暴露途径产生的危害指数。对于致癌效应,计算由吸入Cd引起的致癌风险。结果表明,对于非致癌效应,成都经济区生态风险较高的重金属为Cd和Pb,从总的风险来看,地域差别较明显,以德阳和成都存在的风险最高。谷类对总风险的贡献比例最高,其中又以Cd的贡献最大,其次为Pb。对于致癌效应,研究区的平均致癌风险为7.6×10-6,基本上处于可接受的风险水平,高风险区主要为德阳西部的什邡、广汉和乐山市周围地区,这些地区的大气环境问题应该引起更多的关注。 相似文献
17.
湖州市不同土壤重金属的污染现状 总被引：3，自引：1，他引：3
湖州市是主要的农产品基地，其主要土壤类型有四种，即黄泥土、青紫泥、白泥土和湖松土。样品分析表明重金属元素在黄泥土和青紫泥中较高，白泥土和湖松土中较低。大多数重金属元素相对下蜀土是富集的，超过自然背景值的元素有Cu,Cd及部门土壤中的Pb和Hg。有机质、pH值和Eh值对重金属的含量和化学形态有影响，有机质愈高，重金属的含量愈高；pH值接近中性，重金属的含量亦高。土壤的氧化条件可使大多数重金属变为高价离子，它们的化合物活性较低，但Cr^6 易被植物吸收。湖州土壤中重金属的高值点与工业污水排放和大气沉降有关。土壤中对农作物有危害的重金属元素为Cd和Hg，局部地方为Pb。 相似文献
18.
Bioaccumulation of heavy metals in some fauna and flora 总被引：1，自引：2，他引：1
B. C. Gbaruko M.Sc Ph.D. O. V. Friday M.Sc Ph.D. 《International Journal of Environmental Science and Technology》2007,4(2):197-202
Bioaccumulation of heavy metals in fauna and flora in the Ijaw area of the Niger Delta of Nigeria were investigated. The fauna-molluscs and Crustacea, and flora Hibiscus esculentus and vernonia amygdalina were selected for this study. Results show that Molluscs and Crustacea accumulate considerable amounts of heavy metals. Higher levels of all the metals determined Hg, Pb, Cr, Cu, Ni, and Zn were observed in the shells than in the fleshly tissues. Hibiscus esculentus and vernonia amygdalina also accumulated these heavy metals. The mercury levels in the roots of Hibiscus esculentus and vernonia amygdalina is 0.010 μg/g ± 0.00, while the stem 0.17 ± 0.03 μg/g and leaves 0.25 ± 0.02μg/g was recorded for the v. amygdalina. The H. esculenta fruit has lead levels of 0.22 ± 0.03 μg/g. The levelsof Cu, Ni, and Zn are generally higher than those of Hg, Pb and Cr in all the samples analyzed. There is a growing concern about the physiological and behavioral effects of environmental trace metals in human population. The toxicity of lead at high levels of exposure is well known but of a major concern is the possibility that continual exposure to relatively low levels of these heavy metals through the consumption of these fauna and flora may entail adverse health effects. 相似文献
19.
20.
The contents of Pb, Cd, Cr, As, and Hg was investigated in the neighboring areas of a lead smelting enterprise and the metals contamination of soil was evaluated with the methodologies of the single factor index and Nemerow integrated index. It is found that the content of heavy metals in the neighboring areas has no obvious difference from the reference points. And the soil contamination of heavy metals varies by elements, the contamination index follows the pollution order： Cd〉Hg〉Cr〉As〉Pb. The pollution degree of Cd is at high level and Hg at low level, but Cr and As reached the warning level. Therefore, the lead smelting enterprises should not only control lead but also other heavy metals as Cd. 相似文献