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1.
In this study, we compared the spatial distribution of total metals (Cu, Pb, and Zn) and bioaccessible metals, which were quantified by incubating sediments with the digestive fluid of sipunculans Sipunculus nudus, in natural sediments of the Pearl River Estuary (PRE). The spatial distribution of bioaccessible metal was not the same as that of total metals in PRE sediments, which were mainly controlled by fine-grained size, total organic carbon (TOC) and Fe. Geochemical factors were important in interpreting this different spatial variation. The similar spatial variations of bioaccessible Cu and total Cu were related to TOC in PRE sediments. Differently from the total Zn, a higher bioaccessible Zn was detected near the West Channel of PRE because of a lower TOC. However, the distribution of bioaccessible Pb was not significantly related to any sediment geochemistry. This study provides a more accurate view of metal pollution in the PRE natural sediments.  相似文献   

2.
Introduction Hailing Bay located in western Guangdong province is an important marine aquaculture base and a famous scenic spot. Moyang River which flows across Yangjiang is the major runoff and polluted source in the sea area of Hailing Bay. Hailing Bank ( approximately 5 000 m ) which was built to connect Hailing Island and the continent in 1964 has blocked the natural circulation of suspended sand and pollutants in seawater. Water flux through the Yangjiang harbor extensively decreases …  相似文献   

3.
通过现场调查研究报道了长江口及邻近海域表层沉积物中重金属、有机碳、石油类、硫化物以及氮磷的分布、来源以及沉积物环境质量.结果显示,长江口及邻近海域表层沉积物中重金属、有机碳、石油类、硫化物以及氮磷的分布很不均匀,除硫化物外,重金属、有机碳、石油类以及氮磷基本呈现长江口和杭州湾东北近岸的上海外海出现高值,其他区域浓度较低...  相似文献   

4.
红海湾底质重金属分布与背景值探讨   总被引:3,自引:0,他引:3  
红海湾表层沉积物中Zn,Cd,Cu,Pb含量呈湾顶高于湾中部和湾口的分布特征,在河口潮间带形成污染区。根据背景区沉积物重金属平均含量和2倍标准差,提出用红海湾表层沉积物中Zn,Cd,Cu,Pb,Ni,Cr的背景上限(分别为90,0.65,20,55,30,45mg·kg~-1干重)作为背景参考值。红海湾表层沉积物中Zn,Cd,Cu,Pb呈显著的正相关关系,推测四者具有相似的来源。  相似文献   

5.
为了解大亚湾沉积物中重金属分布及污染状况,于2016年8月对大亚湾海域表层沉积物中重金属元素(As、Cd、Cr、Pb、Zn和Cu)展开调查,并将获得的各元素含量与粒度、Fe、Mn和总有机碳(TOC)等相关理化要素进行相关性分析。结果表明:大亚湾沉积物中重金属受陆源输入影响较大,含量基本呈现为沿岸高、湾内低的趋势,总体质量较好,基本符合第一类海洋沉积物质量标准要求;澳头湾和范和港附近海域人类活动密集,重金属含量较高。通过相关性分析结果发现,大亚湾重金属主要来源为岩石的风化和侵蚀、工业污水排放和渔业养殖等;Cu与铁锰氧化物结合性弱于其他元素,在还原性环境中被沉积物吸附形成金属Cu硫化物可能是喜洲岛附近海域Cu元素含量异常高值的原因;作为湾内有机质主要来源的水生浮游生物的生长状态对Cr、Zn和Pb含量影响较大;Cr、As和Pb与粉砂结合为主,Zn与粘土结合为主。  相似文献   

6.
Between 1980 and 1984 extensive studies were carried out in the Baltic Sea on trace metals (Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb and Zn) in water, suspended matter and sediments. The results enabled the influence of different factors on metal distribution patterns to be considered. The vertical profiles of dissolved and particulate metals in waters of the central deep basins reflect influences caused by oxygen deficiency and anoxic conditions in near-bottom water layers. Peculiarities at Station BY15 in the Gotland Deep included high dissolved Fe, Mn and Co concentrations and remarkable enrichment of Zn (0.64%), Cd (51 μg g−1) and Cu (0.15%) in particulate matter from the anoxic zone. Manganese-rich particles were accumulated above this layer.In fine-grained soft sediments below anoxic deep waters, maximum contents of Cd, Cu and Zn were observed, relative to other coring sites, between Bothnian Bay and Lübeck Bight. The Hg content in sediments probably reflects the joint flocculation with organic matter. Land-based sources seem to play the leading part for maximum lead contents.  相似文献   

7.
莱州湾沉积物粒度与重金属分布特征   总被引:1,自引:0,他引:1  
作者依据2019年8月份莱州湾海洋沉积物调查资料,分析了该海域表层沉积物粒径组成、重金属时空分布特征并评价了其生态风险。结果显示,莱州湾沉积物分为砂质粉砂、粉砂、粉砂质砂和砂4种类型,以砂质粉砂为主,其次为粉砂与粉砂质砂,再次为砂,中值粒径平均58.956μm;表层沉积物中Cr、Zn、Pb、Cu、As、Cd、Hg和TOC平均含量分别为57.6、52.6、18.7、15.3、9.14、0.130、0.0234 mg/kg和0.222%;由于河流排海物质和莱州湾内潮流运动,导致Cu、Pb、Zn、As、Cr和Cd基本呈现中部海域含量较高,西部海域高于东部海域的特征,东南部海域Cd、Hg与矿产资源的开发相关;14.3%的站位综合潜在生态风险属于中生态风险,Cd对综合潜在生态风险指数的贡献率最高,为主要潜在生态风险因子;研究区域中重金属Cu、Zn含量的分布与沉积物粒径和有机碳的含量密切相关。  相似文献   

8.
Heavy metal concentrations in the surface sediments of specially managed Ulsan Bay were investigated to determine metal distribution, pollution status and its ecological risk using pollution indices (enrichment factor and geo-accumulation index), potential ecological risk index and sediment quality guidelines (SQGs). The order of mean concentration (mg/kg) of metals was Zn (361.9) > Cu (95.6) > Pb (90.7) > Cr (64.7) > Ni (32.2) > Co (16.6) > As (15.8) > Cd (0.40) > Hg (0.16) in sediments of Ulsan Bay. Spatial distribution of metals in sediments showed a significantly higher concentration near industrial complexes, indicating that metal pollution is caused by anthropogenic sources. The results of enrichment factor (EF) and geo-accumulation index (Igeo) showed that sediments were significantly accumulated with Cu, Zn, As, Cd, Pb and Hg, indicating moderate to very severe enrichment (pollution) by these metals. Based on the potential ecological risk index, Hg and Cd posed a very high and a considerable potential ecological risk. Cu and As posed a moderate potential ecological risk, while, other metals (Cr, Co, Ni, Zn and Pb) rarely posed any potential ecological risk to the coastal environments. The sediments in Ulsan Bay showed a very high level of ecological risk, dominated by Hg and Cd. Metal concentrations in sediments were 80% for Cu, 96.7% for Zn, 50% for As, 70% for Pb and 50% for Hg above the threshold effects level (TEL), respectively.  相似文献   

9.
Concentrations of P and of heavy metals (Zn, Cd, Pb, Cu) were determined in sediment cores from the Peel-Harvey Estuary in Western Australia. Two cores were extracted, each representing one of the two basins of the estuary. Sediments were dated by surplus210Pb, by137Cs and by changes in the Fe/S ratio. Increasing exports of P from the mainly agricultural catchments have resulted in more than a doubling of both total P and acid extractable inorganic P in sediments of the estuary. Accumulation of P in the estuary is less than expected for complete retention of inputs of P from the major tributaries. Historical data show that since 1950 average concentrations of dissolved inorganic P have approximately doubled in the Peel Inlet and increased by times seven in the Harvey Estuary. Increases in concentrations in surface sediments of acid extractable Zn, Cd, Pb and Cu are noticeable in the Peel Inlet, and of Zn and Cd in the Harvey Estuary. The greatest increase, relative to background, is shown by Zn. Concentrations of extractable Zn and Cd in surface sediments are similar to those estimated from average concentrations in the water column for equilibrium adsorption to organic matter in sediments. Extractable Pb is greater than estimated for equilibrium adsorption to sediments. Extractable Cu is of the order of what can be expected for equilibrium adsorption to sediments in the Peel Inlet, but is less than expected in the Harvey Estuary.  相似文献   

10.
The Neuse River estuary is part of the large Albemarle/Pamlico estuarine/lagoonal system (APES) of North Carolina. Exchange between the APES and the open ocean is restricted to inlets in the Outer Banks barrier islands. Freshwater discharge of the Neuse River is low in relation to the size of its estuary, so that the estuary is normally brackish over most of the area which accumulates fine-grained sediments. Mud (silt + clay) accumulation rates are low ( 6 mm year−1).From the mud distribution and the dynamics of suspended sediment in the estuary it has been inferred that the Neuse retains fines efficiently, with probable episodic (high discharge) losses seaward, to Pamlico Sound.As part of a study of particle transport, deposition, and accumulation in the Neuse estuary, we have collected radiochemical data (10 cores) and chemical data (seven cores) on sediment cores from the main channel of the estuary between New Bern, North Carolina and the estuary mouth. K/Al increases in the lower estuary, consistent with earlier reports of increasing illite in the clay fraction. Landward transport of sediment from Pamlico Sound is the most plausible explanation for the increasing K/Al (illite). A marine sediment source may, therefore, be important for the lower estuary.The distribution of sediment inventories (quantities per cm2 of sediment column) of particle-reactive radionuclides is consistent with the hypothesis of landward sediment transport. Inventories of excess 210Pb, 137Cs, and 239,240Pu are coherent through the estuary and show the effects of particle redistribution processes on regionally uniform inputs. To obtain excess (anthropogenic) Zn and Cu, we use metal/Al normalization to estimate natural backgrounds. Anthropogenic metal inputs are concentrated at the head of the estuary, and sediment inventories of excess Zn and Cu generally decrease seaward. Normalization of the excess Zn and excess Cu inventories to excess 210Pb inventories corrects the raw metal inventories for effects of lithology and sediment redistribution. The normalized excess Zn inventory decreases smoothly seaward, while the normalized excess Cu inventory shows an unexplained mid-estuary maximum. Low normalized inventories of anthropogenic metals at the estuary mouth indicate that little modern riverine sediment is stored there.Increasing K/Al (illite) and decreasing anthropogenic Zn and Cu in the lower estuary are thus both consistent with a predominantly marine sediment source. We conclude that landward transport of muds from Pamlico Sound has contributed significantly to the sediment balance of the lower Neuse estuary.  相似文献   

11.
泉州大港湾海水、沉积物及水产生物体内重金属的含量分布   总被引:14,自引:1,他引:14  
根据1997年7月大港湾海域环境调查资料,着重分析了大港湾海水、表层沉积物及水产生物体内重金属的含量及分布。结果表明:大港湾海水中Cu,Pb,Cd,Zn的含量均低于渔业水质标准,大港湾湾顶水域,海水和表层沉积物中Cu,Pb,Cd,Zn的含最明显高于湾口水域:湾南部水域高于北部水域。文中还根据《海洋沉积物质量》、《无公害食品》、《食品中锌限量卫生标准》、《海洋生物质量》标准对表层沉积物和6种水产生物的重金属污染程度进行评价,结果大港湾的水产生物体内的重金属含量均未超标,但沉积物中的Cd含量已超标。  相似文献   

12.
胶州湾潮间带沉积物主要污染来源及分布特征   总被引:2,自引:0,他引:2       下载免费PDF全文
系统地在胶州湾潮间带获取表层沉积物样品,对沉积物中有机污染物(有机质、石油类),重金属(Hg,Cu,Pb,Zn,Cd,Cr,As)及硫化物进行了定量测定;对潮间带中各物质的主要污染来源和空间分布特征进行了分析。结果表明:胶州湾潮间带沉积物中主要污染分别来源于工业排污和生活污水的排放,交通污染的降水、降尘等。调查区重金属对该海域的生态危害程度从大到小为HgAsCuCdPbCrZn,与其他海域相比较,胶州湾潮间带中Hg和Cu的污染尤为突出。  相似文献   

13.
Marine surficial sediments, intertidal molluscs and reed leaves collected in the Bay of Follonica are slightly contaminated by Pb, Ni, Zn and Fe. The main pollution sources are the waste water and the atmospheric emission of industrial plants. Probably, the weathering of the pyrite deposits along the eastern coast of Elba Island and adsorption and coprecipitation with hydrous Fe-Mn oxides increase the trace metal concentrations in sediments from the Piombino Channel. Mussels and limpets are contaminated by Hg because of the higher background level of the northern Tyrrhenian Sea.  相似文献   

14.
The results of four MAFF surveys (1975–1980) of the sediments in and around the sewage sludge dumping site in Liverpool Bay are presented. Sediments were analysed for particle size distribution, organic carbon concentrations and concentrations of Hg, Cd, Cu, Zn, Pb, Ni and Cr. Concentrations of organic carbon and metals were found to be elevated in the fine ( < 90 μm) fraction in areas associated with the major inputs of these substances to the bay—near the mouth of the Mersey, near the sewage sludge dumping site and at the dredged spoil dumping site.In an attempt to determine any temporal trends between surveys, stations were grouped into four 8×8 km areas from offshore of the dumping ground to the mouth of the Mersey. Changes in the metal concentrations in sediments in the square nearest the sewage sludge dumping site were larger than in the other squares including that nearest the Mersey. Comparison of temporal trends near the sewage sludge site with the quantities actually dumped showed a correlation between the two, consistent with sewage sludge dumping being a major contributor to the metal levels in fine sediments near the dumping ground.  相似文献   

15.
根据2012年双岛湾海域环境调查资料,研究了海水和表层沉积物中重金属的分布特征以及生态风险。结果显示,双岛湾海域海水中的重金属Cu和Pb在湾中部和湾底的部分站位含量较高,Zn和Cr含量在湾底最高、湾外最低,Cd和Hg在湾底和湾外的含量均高于湾中部,As的分布比较均匀;除Zn和Pb外,其余重金属含量均高于周边其他海域。双岛湾海域沉积物中重金属含量较低,与区域背景值相近,其中重金属Hg和Cd在湾内沉积作用明显,而Cu、Pb和Cr在湾外沉积作用比较明显。相关性分析表明,有机碳含量对双岛湾沉积物中的重金属分布影响不大。生态风险评价结果表明,双岛湾海域海水未受到重金属的污染;表层沉积物中重金属存在中低度的生态风险,具有潜在的不利生物毒性效应,重金属毒性大小依次为Pb>As>Cu>Hg>Cr=Cd>Zn。  相似文献   

16.
Eighteen short cores were analyzed for major and trace metals (Al, Fe, Ca, Mg, Mn, Si, K, Ti, Pb, Zn, Cu, Ni, Cr), 210Pb, 137Cs, and other sediment characteristics, so as to describe the chronology of pollution and calculate metal concentration factors and fluxes. Substantial evidence was found that trace metal profiles are influenced by anthropogenic sources and by changes in sediment composition. Only Zn presents concentrations (up to 13.1 μmol g) and concentration factors (1.3 to 13.2) that can be attributed to heavy contamination. Pb, Cu and Ni, in this order, are less significant. The areal distribution of concentrations and inventories reflects the importance of direct sources, in particular the industrial area of Porto Marghera and the Dese river. The inventories of excess metals, above pre-industrial levels, were determined for each core and the three different parts of the study area, the amounts of Zn accumulated in sediments are 11.0 Mmol, 5.1 Mmol and 0.37 Mmol in the Campalto, S. Erasmo, and Palude di Cona areas, respectively. Ruxes were also calculated and compared with those suggested for the atmospheric delivery by Cochran et al. [(1995)b. Atmospheric fluxes of heavy metal contaminants to the Venice Lagoon, Rapp. Comm. Int. Mer Médit., 34, 136.], the atmospheric contribution is predominant or significant in many cases, especially at sites far from the major local inputs. Concentrations and fluxes show a significant increase in the anthropogenic metal supply starting from the second decade of this century, with maximum inputs in the period between the (1930)s and the (1970)s. At some stations a decrease in heavy metal contamination of surficial sediments was found and this could be ascribed to a reduced input of pollutants in recent years.  相似文献   

17.
利用 1 997年 7月的渔业环境监测资料 ,分析了福建省兴化湾海水、表层沉积物及水产生物体内重金属的含量及分布 ,重金属与有机质含量之间的相关关系和水产生物对重金属的富集情况。结果表明 ,兴化湾海水和水产生物体的重金属含量均未超标 ,但大部分沉积物Pb,Zn的含量超标。  相似文献   

18.
According to the results of the comparative study performed of the littoral sediments sampled in small inlets of Kandalaksha Bay (the White Sea in the Russian Arctic), the metals (Fe, Mn, Cu, Zn, Pb, Cr, and Li) occur mainly in a biogeochemical-stable mineral-incorporated form, which comprises 77–99% of the total metal content. The ratio of the liable form, which is easily extracted by a weak acid, is on average 3.2% for the total Fe, 2.0% for Mn, 1.7% for Cr, 5.6% for Pb, 5.8% for Zn, 6.5% for Cu, and is negligible for Li. The concentrations of the most studied trace metals are below the threshold level according to the environmental quality guidelines (the sediment analysis). The ratio of the metal forms evidences the natural origin of the elevated concentrations of both Zn and Cr in the sediments.  相似文献   

19.
《Marine Chemistry》1987,21(3):229-248
Surficial sediments of a Scottish sea loch exhibit enrichment profiles for the minor metals Cu, Pb and Zn. 137Cs data indicate enrichment during the last 20–40 years of deposition. Variations in the onset of enrichment between sites within the fjord, which have similar accumulation rates, infer that whilst the metal inputs may originally have been of an anthropogenic nature the present distribution of the metals in the sediments is controlled by organic matter diagenesis. These processes are especially important within the sulphate reducing zone. This suggestion is supported by the similar behaviour of the heavy metals and I/Corg ratios in the sediments. Diagenetic recycling of Pb may also explain discrepanceis that were observed between 210Pb and 137Cs chronologies. The source and diagenetic remobilisation of these elements is discussed with relation to the fate of anthropogenic metals in coastal sediments.  相似文献   

20.
Concentrations of heavy metals (Co, Cr, Cu, Fe, Ni, Pb and Zn), particulate organic (POC) and nitrogen (PON), particulate inorganic carbon (PIC) and opal content were measured in 35 surface sediment samples taken in the Ferrol Ria (Galicia, NW Spain). This ria is a semi-enclosed embayment receiving inputs from industrial and urban effluents. The restricted water exchange between the ria and the shelf has led to a significant accumulation of contaminants within the embayment. Two main factors controlled the metal distribution and concentrations in the bay: (1) contamination point sources and (2) distribution of the organic-rich sediments. Zn, Cu and, to a lesser extent Pb, were the metals most contaminated in the bay, with average enrichment factors (AEF)—defined as the mean metal concentration in the bay divided by the background value reported for this ria—of 4.7, 5.5 and 2.7, respectively. The highest concentrations for these metals were observed in the vicinity of the point sources. Values found for Zn, Cu and Pb are comparable to other industrialized coastal areas in the world. For Ni, Fe, Cr and Co a negligible to low contamination was found (AEF = 1–2), with the highest concentrations found in the organic-rich sediments.  相似文献   

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