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1.
近年来由于环渤海经济圈的快速发展,渤海接受了来自周边河流、沿岸排污及海上油气开采所产生的大量的重金属等污染物质,使得渤海的生态环境系统面临前所未有的压力。本文采用电感耦合等离子质谱仪(ICP-MS)对采自渤海中部的25个表层沉积物样品中的Cu、Co、Ni、Zn、Pb、Cr、Cd等重金属元素的含量和赋存相态进行了分析,探讨了重金属分布规律、污染状况及来源。研究结果表明,Cu、Co、Ni、Zn、Cr在渤海湾的近岸区域和渤海中部泥质区有较高的含量,而Pb和Cd则在整个研究区的含量都较高;表层沉积物中Cu、Co、Ni、Zn、Cr主要以残渣态形式存在,而Pb和Cd则具有较高的非残渣态含量;生态风险评价结果表明该区表层沉积物未受到Co、Ni、Cr的污染,Cu、Zn、Pb和Cd则为未污染-中等程度污染。重金属元素Co、Ni、Cr以自然来源为主,在沉积物中的分布主要受沉积物物质组成的影响,而Cu、Zn、Pb,尤其是Cd,则受到了人类活动的显著影响。黄河沉积物是研究区表层沉积物中重金属的主要来源,影响范围涵盖了本区大部分区域,但在研究区的北端受到滦河来源物质的影响,渤海湾和研究区中部则受到海河物质和大气沉降来源重金属的一定影响。  相似文献   

2.
Cadmium, lead and copper have been determined in both dissolved and particulate phases for 130 surface-water samples from the coastal zone of Scotland and England in the western North Sea. The concentrations reported are, in general, lower than those published previously for the same area.The distribution of total metal concentration between the dissolved and particulate phases varies for the three elements. The lead distribution is dominated by its associations with particulate material while cadmium shows the reverse behaviour, existing almost totally in the dissolved phase. Copper is intermediate in behaviour, with the dissolved phase generally being dominant.An inverse relationship between salinity and dissolved copper concentration suggests a freshwater origin for this element. It is suggested that sedimentary and/or anthropogenic sources affect dissolved copper concentrations in coastal waters. The dissolved lead distribution reveals plumes of contaminated coastal water. The lead distribution is, however, dominated by associations with particulate material and sediments which produce a sharp concentration gradient close to the coast. The Humber estuary is identified as a significant source of cadmium to the North Sea.  相似文献   

3.
Announcement     
Cadmium, lead and copper have been determined in both dissolved and particulate phases for 130 surface-water samples from the coastal zone of Scotland and England in the western North Sea. The concentrations reported are, in general, lower than those published previously for the same area.The distribution of total metal concentration between the dissolved and particulate phases varies for the three elements. The lead distribution is dominated by its associations with particulate material while cadmium shows the reverse behaviour, existing almost totally in the dissolved phase. Copper is intermediate in behaviour, with the dissolved phase generally being dominant.An inverse relationship between salinity and dissolved copper concentration suggests a freshwater origin for this element. It is suggested that sedimentary and/or anthropogenic sources affect dissolved copper concentrations in coastal waters. The dissolved lead distribution reveals plumes of contaminated coastal water. The lead distribution is, however, dominated by associations with particulate material and sediments which produce a sharp concentration gradient close to the coast. The Humber estuary is identified as a significant source of cadmium to the North Sea.  相似文献   

4.
渤海莱州湾表层沉积物中金属元素分布及环境质量   总被引:3,自引:1,他引:2  
利用X-射线荧光光谱仪、等离子质谱仪或原子荧光光度计测定了莱州湾表层沉积物中金属元素的含量,探讨了它们的分布特征、来源及污染程度,结果表明,沉积物中铜、锌、铅、镉、砷、镍、铬、钴、钒、钪、铁、锰的含量由近岸向湾内递减,莱州湾北部海域的含量大于南部的。银含量高的沉积物主要分布在莱州湾中部偏西南的环流中心区。沉积物中砷和镍含量超过ERL值,潜在生态风险较高。富集系数和主成分分析显示,沉积物中铁、铜、锌、镉、砷、铬、镍、钴、锰、钒和钪为无富集,砷为轻度富集,铅和银为中度富集。铁、铜、锌、镉、铬、镍、钴、锰、钒、砷和钪主要来源于自然源,铅既有岩石和土壤风化产物硅酸盐矿物等自然源的贡献,又受到了人为活动的影响,银主要受人为活动的影响。聚类分析表明,可把莱州湾沉积物分为4类,其中黄河口西北缘沉积物中砷和镍污染生态风险最高,其次是莱州湾中部和北部。  相似文献   

5.
Concentrations of zinc, cadmium, copper, manganese, iron, cobalt, nickel and molybdenum are examined in brown algae, Fucus serratus and F. vesiculosus, from Cardigan Bay, Irish Sea, Great Britain. In both species a seasonal variation in metal content was observed. Zinc, cadmium, copper, iron nickel and cobalt concentrations were highest in the spring and lowest in the autumn, probably reflecting levels of metabolic activity and climatic factors. All the studied elements, except nickel, reached highest concentrations in harbour specimens from Aberystwyth and Aberaeron where rivers draining mineralized areas enter the sea. Outside harbours, marked regional variations were observed in most of the studied elements. Zinc values were highest in the Aberystwyth area while copper and manganese were highest in the northeast part of the bay.Trace-element concentrations varied among different species from the same locality and also varied according to position on the shore.Marine algae may be used to monitor coastal-water trace-metal concentrations, provided a careful sampling procedure is adopted.  相似文献   

6.
Dissolved trace element (copper, nickel, cadmium, zinc, cobalt, and iron) concentrations were measured in surface water samples collected from 27 stations in the San Francisco Bay and Sacramento—San Joaquin Delta during April, August and December of 1989. The trace element distributions were relatively similar for all three sampling periods, and evidenced two distinct biogeochemical regimes within the estuarine system. The two regimes were comprised of relatively typical trace element gradients in the northern reach and anthropogenically perturbed gradients in the southern reach of the estuary. These dichotomous trace element distributions were consistent with previous reports on the distributions of nutrients and some other constituents within the estuary.In the northern reach, trace element and dissolved phosphate concentrations were non-conservative. Simple estuarine mixing models indicated substantial internal sources of dissolved copper (46–150%), nickel (250–500%) and cadmium (630–780%) relative to riverine inputs in April and August, and sizable internal sinks for dissolved cobalt (> 99%) and iron (> 70%) during the same periods. Dissolved zinc fluxes varied temporally, with a relatively large (135%) internal source in April and a relatively small (29%) internal sink in August.Concentrations of many trace elements (copper, nickel, cadmium, zinc, and cobalt) in the southern reach were anomalously high relative to concentrations at comparable salinities in the northern reach. Mass balance calculations indicated that those excesses were primarily due to anthropogenic inputs (waste-water discharges and urban runoff) and diagenetic remobilization from benthic sediments. The magnitude of these excesses was amplified by the long hydraulic residence time of dissolved constituents within the South Bay.The influence of other factors was evident throughout the system. Notably, upwelling appeared to elevate substantially dissolved cadmium concentrations at the mouth of the estuary and authigenic flocculation appeared to dominate the cycling of dissolved iron in both the northern and southern reaches of the system. Biological scavenging, geochemical scavenging and diagenic remobilization were also found to be important in different parts of the estuary. Additional complementary information is required to quantify accurately these processes.  相似文献   

7.
Heavy metal concentrations were measured in the Changjiang Estuary and its adjacent waters. Results from a systematic survey in April 2002 to March 2003 indicate that the ranges of the concentrations of dissolved copper, lead, zinc and cadmium in the study waters are 1.01 - 6.86, 0. 10 - 0.39,3.17 - 9.12 and 0.011 - 0. 049 μg/dm^3 , respectively. Similar to zinc, the behavior of dissolved copper was essentially conservative, but high scatter has been observed for high salinity samples, which can be attributed to the decomposition or mineralization of organic matter by bacteria. Dissolved lead may have active behavior with an addition at high salinity. Overall concentrations of dissolved cadmium increase with salinity. The mean values of these dissolved metals calculated for the surface waters were higher than those for the middle and bottom ones. External inputs of dissolved heavy metals to the surface waters were the likely explanation for these higher values. The maximum seasonal average values of dissolved copper and zinc were found in summer, reflecting higher amounts of riverine input in this season. In contrast, the maximum seasonal average values of dissolved lead and copper were found in winter and the lowest ones in summer, respectively, which might be asso- ciated with a combination of low concentration with heterogeneous scavenging. Concentrations of these dissolved metals found for the Changjiang Estuary fall in the range observed for the other estuaries but are noticeably higher than those from uncontaminated rivers, except for cadmium. Compared with observations for the Changjiang Estuary in the last two decades, it is clear that the Changjiang estuarine waters has been contaminated with copper, lead, zinc and cadmium during China' s industrialization, but concentrations of them have decreased in the last few years.  相似文献   

8.
基于2010年10月国家自然科学基金委东海调查公共航次所获得的数据和悬浮体样品,使用ICP-AES、ICP-MS仪器对悬浮体中的主、微量元素含量进行了测定,对悬浮体中元素组成、空间分布及其影响因素进行了研究,结果表明:长江口及邻近海域悬浮体中主量元素铝、镁、铁、钙等含量为1%~30%,含量以铝为主;微量元素镉、铬、钴、铜、锰、镍、铅、钒等含量为n×10-6~n×10-9,以锰最高;铝与铁、锰以及大部分的微量元素都有良好的相关性,指示这些主量元素以陆源输入为主和微量元素被细颗粒物质吸附为主的特征。水团对长江口及邻近海域颗粒态地球化学组分的空间分布具有重要的影响,其中铝、铁及铬、钴、铜、锰、镍、钒等元素受水团的制约更加显著。  相似文献   

9.
The use of selected organisms as biomonitors of trace metal bioavailabilities allows comparisons to be made over space and time. The concentrations of 11 trace metals (arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel, silver, zinc) were measured in the bodies of two barnacle species, Balanus amphitrite and Tetraclita squamosa, from up to 18 littoral sites from Hong Kong coastal waters in April 1998. These data provide evidence on the geographical variation in metal bioavailabilities at this time, and are compared selectively against historical data sets for 1986 and 1989. Geographical variation in bioavailabilities is clear for several metals, with hotspots for arsenic, copper, nickel and silver at Chai Wan Kok, and for lead in Junk Bay. Victoria Harbour sites head the rankings for silver and arsenic, and Tolo Harbour sites exhibit relatively elevated cobalt, manganese and zinc. Many bioavailabilities of trace metals to barnacles are lower in Hong Kong coastal waters in 1998 than in 1986. The two barnacle species are widespread and the extensive data set presented is a benchmark which can be compared to the results of similar biomonitoring programmes elsewhere in the Indo-Pacific and beyond.  相似文献   

10.
汕头湾表层沉积物重金属元素含量和分布特征研究   总被引:16,自引:0,他引:16  
乔永民  黄长江 《海洋学报》2009,31(1):106-116
于2002年9月在汕头湾采集了13个表层沉积物样品,测定了它们的细粒级组分、总有机质、铝、铁、锰、铜、锌、铅、镉、铬、镍、钴的含量,对其分布特征及其彼此之间相关性进行了分析,并以南海陆架区重金属含量为背景值计算了汕头湾表层沉积物重金属元素的富集系数,结果表明,铁、锰、铜、锌、铅、镉、铬、镍、钴的含量范围分别为2.91%~3.94%,427.85~810.96,24.43~79.49,84.83~248.50,35.56~50.25,0.30~1.75,36.11~74.22,16.99~31.69,8.22~10.87 mg/kg,其分布由汕头湾上游的榕江口至湾口呈波浪状递减(锰除外)。汕头湾表层沉积物中各重金属的富集系数均大于1,其中富集系数从大到小的重金属元素是铜、镉、铅、锌、镍、铬和锰。人为排污、水动力作用、黏土含量、盐度是多数重金属元素分布特征的控制因素。锰的分布特征更多地取决于汕头湾水域的氧化还原条件。  相似文献   

11.
Field sampling of the dissolved and particulate material field downstream of a large volume bucket dredge operating in the lower Thames River estuary near New London, Connecticut, was conducted in order to examine the magnitude and character of the dredge-induced resuspension. These data indicate that large amounts of dissolved phosphate, ammonia, silica, manganese, copper and particulate materials are released into the water column, whereas cadmium concentrations were unaffected. Concentrations in the vicinity of the dredge exceed background levels by two to nine times for the dissolved materials and by two orders of magnitude for particulates. During the ebb cycle, downstream material concentrations decrease rapidly to background within approximately 180 m for dissolved materials and 700 m for particulates.Two mechanisms were found to control the distribution of materials downstream of the dredge: (a) physical transport, including advection, turbulent mixing and diffusion, and (b) geochemical processes (i.e. adsorption, desorption, precipitation, dissolution, etc.). The concentration of dissolved materials downstream of the dredge decrease at a first order exponential rate. The downstream distribution of the dissolved ammonia and silica was found to be consistent with the reactivity experiments (Figure 8) which predicted that PO4 would undergo a decay in concentration in the presence of suspended sediments. Absorption of phosphate onto suspended sediments and gravitational settling of the suspended particulates were the processes. Manganese and copper underwent a dual transformation which involved an initial dissolution, followed by flocculation and possible coprecipitation as MnO2. Cadmium concentrations in the water column were unaffected by the dredging process due to low pore water concentrations.The observed spatial distribution indicates that dredge-induced injection of dissolved and particulate materials is primarily a near field phenomenon producing relatively minor variations as compared to those caused by naturally occurring storm events. These latter systems have been shown (Tramontano, 1978; Bohlen et al., 1979) to produce estuary-wide variations in suspended materials, PO4 and NH4 concentrations increasing the mass of materials in suspension by at least a factor of two. This increase in total suspended load, PO4 and NH4, is nearly an order of magnitude larger than that produced by the dredge.  相似文献   

12.
Dissolved electroactive concentrations of zinc, cadmium, lead and copper in river Rhine and North Sea samples have been measured at natural and lower pH values by differential pulsed anodic stripping voltammetry using a Kemula-type hanging mercury drop electrode. Average concentrations detected in North Sea samples at salinities ? 32‰ S and their range are (in μgl?1): 3.9 (2.0–7.5) for zinc, 0.23 (0.13–0.31) for cadmium, 0.3 (0.1–0.6) for lead and 0.3 (0.25–0.60) for copper (pH 8.1). The APDC-MIBK extracting/concentrating method, followed by AAS measurement applied to the same samples, resulted in 3.9 (2.0–7.5) for zinc, 0.11 (0.01–0.27) for cadmium, 0.5 (0.2–0.9) for lead and 1.6 (0.7–3.2) for copper. A fraction of the electroactive concentrations at pH 2.7 (6.1 for Zn) is electroactive at pH 8.1. The fractions are 100% for Cd, 20% for Cu, 13% for Pb and 40% for Zn. The remaining fractions are partly composed of organically bound species in solution. The low value for lead may be caused by the presence of particulate lead that is dissolved at low pH.Ionic copper and lead species, added separately to seawater at pH 8.1 are removed from the electroactive form, and taken up in (organic) complexes in the same ratio (at least for copper) as the species already present. Added ionic zinc is not removed within the time scale of the measurements (30 min). North Sea water at the natural pH has a complexing capacity, probably due to the presence of dissolved organic compounds, in a concentration equivalent to 3.10?7M copper. The complexing capacity is zero at pH 2.7. The usual method of standard addition for the determination of electroactive copper and lead concentrations may lead to erroneous results in samples where complexation of this type occurs.  相似文献   

13.
The mechanisms of incorporation of minor transition metals into marine manganese nodules are discussed on the basis of differential chemical leaching.A small portion of iron and manganese in deep-sea nodules was dissolved in dilute acetic acid. Hydrogenous cobalt and nickel in nodules were also slightly leached with the acid solution, while 50–60 % of hydrogenous copper and zinc were leached. This difference suggests that the greater parts of hydrogenous cobalt and nickel are present in the lattices of manganese oxide phases, while the major parts of hydrogenous copper and zinc are present in the sorption sites of manganese oxide phases.The enrichment of minor transition metals in manganese nodules may be controlled by their substitution for manganese atoms in manganese oxide lattices after their sorption on manganese oxide phases.  相似文献   

14.
Concentrations of cadmium, copper, iron, lead, manganese, nickel and zinc were investigated in two species of mussel from the Kuril Islands in the north-western Pacific Ocean: the short-lived mussel Mytilus trossulus and the much larger and longer-lived Crenomytilus grayanus. The concentrations of most elements were low, and these reported levels are believed to reflect background values for pristine locations. However, both iron and zinc concentrations were elevated in some samples taken from areas of hydrothermal vent activity, and these are believed to reflect the enrichment of the two metals in solution at such sites. Furthermore, the concentrations of cadmium were unusually elevated in both species of mussel, especially in the longer-lived C. grayanus. The high accumulation of cadmium in mussels from the Kuril Islands is believed to reflect regional upwelling, but it is also postulated that filtration rates of the mussels are high due to low levels of suspended matter, and this leads to a high assimilation efficiency for cadmium. The distribution of cadmium amongst the tissues of C. grayanus is also reported, and the need for further ecotoxicological studies in the area is proposed.  相似文献   

15.
Dissolved and total dissolvable manganese concentrations have been measured at four stations in the western North Atlantic Ocean. Total dissolvable manganese concentrations are high in surface waters, decrease to uniformly low levels throughout the bulk of the water column, and increase in the bottom nepheloid layer. Dissolved Mn (Mnd) concentrations follow the total dissolvable concentrations throughout the surface and deep waters but do not increase in the near-bottom waters.Deep water concentrations of Mnd decrease from 30 ng l?1 in the Newfoundland Basin to 20 ng l?1 in the Sargasso Sea. This change and other features of the deep water distribution of dissolved manganese could be associated with the slow oxidation of Mn2+ to MnO2. There is also evidence at one station of scavenging of manganese from the dissolved phase in the near-bottom layer which may again be related to the kinetics of manganese oxidation.  相似文献   

16.
On the basis of the generalized data of multiannual observations (1985–1994), we analyze the seasonal variability of the vertical and spatial distributions and composition (Csos, Nsos, Csos/cha, and C/N) of suspended organic substances (SOS) in the shelf zone and in the upper active layer of the abyssal part of the Black Sea. The results of our analysis enable us to conclude that only a narrow coastal band of the shelf in the northwest and west parts of the sea suffers to an extremely pronounced anthropogenic impact, which manifests itself in a significant increase in the mass of suspended organic substances. The formation of new organic substances and, hence, the mass of suspended organic substances in these regions attain the level of eutrophic waters in the late-spring and summer periods. In the open-sea region, the anthropogenic impact is less pronounced and the spatial distribution of suspended organic substances is determined by the general dynamics of waters and the intensity of phytoplankton production. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

17.
Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows: Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer (SSL) in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complex- ing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China's coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly.  相似文献   

18.
To establish a base line against which future pollution may be measured, eight common commercial species of New Zealand sea fish were analysed for cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc. One sample of edible muscle tissue was analysed for each of 70 samples of each species. The internal organs of up to five specimens of each species were also analysed. The fish studied were: kahawai, Arripis trutta, trevally, Caranx lutescens, tarakihi, Cheilodactylis macropterus, snapper, Chrysophrys auratus, moki, Latridopsis ciliaris, hapuku, Polyprion oxygeneios, kingfish, Seriola grandis and gurnard, Trigla kumu.

Although, none of the edible parts of the fish appeared to have trace element levels likely to be a public health problem (cadmium 0.002–0.02 ppm, chromium 0.01–0.04 ppm, copper 0.04–0.95 ppm, iron 0.9–13.5 ppm, lead ‘ 0.14–0.95 ppm, manganese 0.04–2.00 ppm, nickel 0.01–0.08 ppm, zinc 2.0–36.0 ppm), some of the organs (particularly the liver) had relatively high concentrations of elements such as cadmium (up to 54 ppm). Only if some industry were to seek to exploit internal organs of fish for human consumption would such levels become important. There was some evidence for a relationship between trace element concentrations and fish size for copper in kingfish and snapper, iron in hapuku, manganese in gurnard, and for zinc in kingfish and tarakihi. Some element pairs such as copper and zinc, iron and manganese, appeared to have concentrations which were mutually related. It was assumed that the elemental concentrations reported represent natural levels and are not the result of significant man‐made pollution because there are no major industries or large urban centres adjacent to the fishing grounds.  相似文献   

19.
Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows: Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer (SSL) in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complexing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China' s coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly.  相似文献   

20.
Specimens of Bathymodiolus azoricus were sampled along the Mid-Atlantic Ridge at the Menez Gwen, Lucky Strike and Rainbow hydrothermal fields. Individual shells (n = 51), through the weight range 0.62 to 15.70 g, were analyzed for their magnesium, strontium, iron, manganese, copper, zinc and cadmium concentrations. Amongst the marine molluscs the shell of B. azoricus is confirmed as being particularly impoverished in strontium (mean 943 microg g(-1)). Trace metal concentrations in the shells decreased in the order Fe> Mn> Zn> Cu> Cd. Despite originating from trace metal rich environments mean concentrations were low (37.9, 13.2, 10.7, 1.1 and 0.7 microg g(-1), respectively). Irrespective of geographical origin magnesium, strontium and copper concentrations were primarily dictated by shell weight. In contrast cadmium concentrations were elevated in shells from the Rainbow field and ambient seawater chemistry imparted site specific chemical fingerprints to the shells with respect to the iron to manganese ratio.  相似文献   

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