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1.
The macrobenthic community structure and characteristics of sediments were studied in samples collected seasonally at five stations in the lower mesotidal Douro estuary, Portugal. Sediment characterisation included grain size distribution, total-recoverable metals (Al, Fe, Mn, Zn, Cu, Cr, Pb, Ni and Cd), acid-volatile sulphides (AVS) and simultaneously extracted metals (SEM) and total organic matter contents. Spatial variation surpassed temporal variation both in terms of environmental parameters and community structure. Clear anthropogenic contamination in terms of Zn, Cr, Cu and Pb, and a positive SEM-AVS, indicating the potential bioavailability of these metals, were detected on the north bank of the estuary. Multivariate analysis revealed that in addition to natural sediment characteristics, the anthropogenic metal contamination was influencing the macrobenthic community structure. In fact, greater concentrations of Zn, Cr, Cu and Pb were associated with lower number of species and/or diversity. Finally, the dry weight-normalised metal concentrations appeared as a more useful tool than the SEM-AVS model in predicting disturbance of the macrobenthic community in the studied area.  相似文献   

2.
Spatial distribution of metal concentrations in the surface sediment samples collected from 16 marine locations covering different coastal ecosystems such as mangroves, seagrasses, dead coral and sandy beaches of the Andaman islands, India was studied. pH, EC, sediment grain size and heavy metal (Al, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn) concentrations were determined and contamination factor (CF) and geo-accumulation index (Igeo) were calculated to understand the pollution status of the study area based on the background values. CF of different heavy metals has revealed that different metals have different levels of accumulation viz. Al: 0.01–0.22, Mg: 0.38–1.85, Fe: 0.06–0.74, Mn: 0.04–1.18, Cu: 0.18–2.93, Cr: 0.52–12.6, Zn: 0.3–1.39, Ni: 0.06–0.89, Pb: BDL–0.74, Co: 0.1–0.35 and Cd: 2.3–12.9. In general the metal concentration was less in these ecosystems when compared to similar ecosystems of mainland of India. Concentration of some metals like Cr and Cd was comparatively higher than the background values which is an important issue of concern to the coastal managers of the region. Spatial data on heavy metals, collected now, would help the coastal zone managers to identify the vulnerable sites and take remedial actions.  相似文献   

3.
This paper presents the geochemical study of sediments along Ube, Suo-Oshima, and Kasado Bays in the Seto Inland Sea of Japan. We examined the distribution and abundances of 13 elements (As, Pb, Zn, Cu, Ni, Cr, Sr, Ca, Fe, Ti, P, Mn, and total S) in 40 coastal and river sediment samples, to evaluate the factors controlling their abundances, possible sources, and environmental implications. Average concentrations of As, Pb, Zn, Cu, Ni, and Cr at Ube were 12, 26, 86, 16, 43, and 92?mg/kg, 6, 25, 31, 8, 9, and 29?mg/kg at Kasado, and 5, 20, 28, 3, 5, and 18?mg/kg at Suo-Oshima, respectively. Average As, Pb, Zn, and Cr concentrations at Ube were comparable or enriched relative to those of the upper continental crust and Japan upper crust, whereas most major elements, Cu, and Ni were depleted at Kasado and Suo-Oshima. Enrichment factor values show low to moderate enrichment of Zn, Ni, and Cr, whereas As and Pb show significant contamination at some sites, suggesting contributions from anthropogenic sources. Anthropogenic contributions of most metals mainly originate from natural processes; however, As and Pb ranges of 73–79 and 66–81?%, respectively, confirm their anthropogenic contribution. Factor analysis and correlation matrices suggest that elevated metal concentrations at Ube, especially in samples located in the river basin, may be controlled by Fe–Mn oxy-hydroxides. Deposition of metals at Kasado and Suo-Oshima might be controlled by non-ferrous metal (i.e., aluminosilicates), sediment grain size, or source rock composition (granite and gneiss).  相似文献   

4.
Total metal concentrations in sediments from within Ensenada and El Sauzal Harbors are generally higher than at the mouths. Grain-size analyses suggested that this enrichment could be due to the presence of fine-grained sediments in the inner part of the harbors rather than to anthropogenic perturbations. The (Me/Al)(sample) ratios for Pb, Co, Ni and Fe were significantly higher for Ensenada Harbor relative to El Sauzal Harbor, whereas the ratios for Cd, Mn, Zn and Cu were statistically equivalent for both harbors. Calculated enrichment factors [EF(Me)=(Me/Al)(sample)/(Me/Al)(shale)] indicated that the metals showing slight enrichment were those associated with anthropogenic contamination (Pb, Zn), or probably related to primary productivity in the water column (Cd, Co). The levels of most of the metals were not greatly enriched, a consideration that is of the utmost importance when contamination issues are at stake.  相似文献   

5.
Z. Seisuma  I. Kulikova 《Oceanology》2012,52(6):780-784
The comparison of spatial and temporal distribution of Hg, Cd, Pb, Cu, Ni, Zn, Mn and Fe concentrations in sediments from the Gulf of Riga and open Baltic Sea along the coastal zone is presented for the first time. There were considerable differences in Pb, Zn, Mn and Fe levels in sediment at various stations of the Gulf of Riga. A significant difference of Cd, Pb, Cu, Ni, Zn levels was found in sediments of various stations in the open Baltic coast. The amount of Cd, Pb, Cu, Ni, Zn and Fe levels also differed significantly in the sediments of the Gulf of Riga in different years. A considerable yearly difference in amount of Hg, Cd, Pb, Cu, Ni and Mn levels was found in sediments in the open Baltic coast. The essential highest values of Pb and Zn in coastal sediments of the open Baltic Sea are stated in comparison with the Gulf of Riga. The concentrations of other metals have only a tendency to be higher in coastal sediments of the open Baltic Sea in comparison with the Gulf of Riga. Natural and anthropogenic factors were proved to play an important role in determining resultant metals concentrations in the regions.  相似文献   

6.
Distribution and sources of heavy metals in the sediment of Xiangshan Bay   总被引：2，自引：0，他引：2  
Heavy metals in the surface sediments and sediment core from the Xiangshan Bay, a mariculture base on the coast of the East China Sea, were determined by inductively coupled plasma mass spectrometry(ICP–MS) in order to evaluate their levels and sources. The results showed that the levels of Cu, Pb, Zn, and Cr in the sediments of the bay have been generally influenced by anthropogenic inputs since the founding of the People's Republic of China. In particular, Cu and Zn were polluted to some extent, as evidenced by high enrichment factors. Organic matter, grain size, wastewater discharge, and low energy hydrodynamic environment played dominant roles in the heavy metal enrichment in the sediments. The ratio of terrigenous source to marine biogenic deposit of trace metals in the sediments was calculated, revealing that terrigenous inputs were the main source of Cu, Pb, and Zn, while biological pellets contributed much more to the enrichment of Cr and Cd. Considering the influence of biological sources on the enrichment of Cd and Cr, and the fact that the sediment has been polluted by Cu and Zn, the development of mariculture and discharge of wastewater into the Bay should be restricted.  相似文献   

7.
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   

8.
烟台近岸典型生态区沉积物重金属形态分布及其污染状况   总被引：3，自引：0，他引：3  
运用Tessier连续提取法,对烟台海岸带3个典型生态敏感区表层沉积物重金属Cr、Cu、Cd、Pb、Zn、Ni的形态分布和污染状况进行了分析研究。结果表明,研究区域中河口区与排污口区重金属Cr、Cu、Cd、Zn和Ni的含量较高,尤其是Cd污染严重。养殖区基本符合海洋沉积物质量第1类标准;重金属Cr、Cu、Pb、Zn和N...  相似文献   

9.
The range and spatial distribution of metal concentrations in the Chiloé Interior Sea were investigated from 37 surface sediment samples collected during the ‘CIMAR 10 Fiordos’ cruise. Grain size distribution, total organic carbon and nitrogen, δ13C, major (Al, Fe, and biogenic opal) and trace (Cd, Co, Cu, Ni, Pb, and Zn) elements were determined. Metal background concentrations of each metal in sediment were defined from linear regression equations of metal versus Al, as baseline information for future research on the status of sediment contamination in the Northern Patagonian marine area. Metal levels in Chiloé sediments were of the same order of magnitude as uncontaminated sediments around the world and contamination can be considered negligible-moderate (normalized enrichment factors lower than 3) in this Southern Pacific Region. The Chiloé Interior Sea can be segregated into two zones on the basis of metal content by applying a principal component analysis. The first pertains to inner fjords and it has terrestrial origin (associated to Co, Cu, Pb, Zn) and the second zone features channels and gulfs of a predominantly marine source (Cd, Cu). Nevertheless, only one background equation is needed to predict metal concentrations in the natural sediment of the Chiloé Interior Sea.  相似文献   

10.
粤西湛江港海底沉积物重金属的分布特征与来源   总被引：2，自引：0，他引：2  
2004年9月23日至10月5日对湛江港海洋沉积物中金属元素的含量及分布进行了调查。共采集样品20个,采用王水-氢氟酸消解,电感耦合等离子体发射光谱法测定样品中的金属元素As、Cd、Co、Cr、Cu、Ni、Pb、Zn、Al、Ca、Fe、Mg和Mn。结果发现,湛江港大多数区域的沉积物未受污染,但霞山区港务局码头附近海域受到Cd、Cu和Pb的轻度污染,特呈岛养殖区也受到Cu的轻度污染。主成分分析结果表明,Al、Cd、Co、Cr、Cu、Fe、Ni、Pb和Zn主要通过陆源输入进入近岸水域的沉积相中,Ca、As、Mg和Mn主要通过海洋环境中水相和沉积相的相互作用进入沉积相中。结合其它调查结果认为,湛江港的Cd污染在水相、沉积相和生物相中均已存在,应引起有关部门的高度重视。  相似文献   

11.
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   

12.
The distribution, partitioning and concentrations of trace metals (Cd, Cr, Cu, Fe, Mn, Pb and Zn) in seawater, including dissolved and particulate phases, and in copepods in the ocean outfall area off the northern coast of Taiwan were investigated. Normalization of metal concentrations to the background metal concentration to yield relative enrichment factors (EF), which were used to evaluate the contamination of dissolved and particulate trace metals in seawater around the ocean outfall. The EF results indicated that the outfall area was significantly contaminated by dissolved Fe and Zn, and by particulate Fe, Cr, Cu, Pb and Zn. In addition, most trace metals were chiefly in the particulate phase. The average percentage of total metal concentrations (dissolved plus particulate phases) bound by suspended particulate matter followed the sequence Al(95%) = Mn(95%) > Pb(88%) > Cu(86%) > Fe(72%) > Zn(32%) > Cr(17.5%) > Cd(3.4%). Therefore, metal contamination is better evaluated in solid phase than in the dissolved phase. The concentration ranges of trace metals in the copepods, Temora turbinata, Oncaea venusta and Euchaeta rimana, near the outfall were: Cd, 0.23-1.81 microg g(-1); Cr, 16.5-195 microg g(-1); Cu, 14-160 microg g(-1); Fe, 256-7255 microg g(-1); Mn, 5.5-80.8 microg g(-1); Pb, 2.6-56.2 microg g(-1); Zn, 132-3891 microg g(-1); and Al, 0.21-1.13%. Aluminum, and probably Fe, seemed to be the major elements in copepods. The concentrations of trace metals in copepods, especially Temora turbinata, near the outfall were generally higher than those obtained in the background station. The mean increase in bioconcentration factor of metals in copepods ranged from 4 to 7 and followed the sequence Al(6.4) > Cu(6.2) > Fe(6.0) > Zn(5.7) > Pb(5.6) > Cr(5.5) > Cd(5.1) > Mn(4.7). Therefore, marine copepods in the waters of northern Taiwan can accumulate trace metals over background concentrations and act as contamination indicators.  相似文献   

13.
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   

14.
Concentrations of Cd, Cu, Cr, Co, Ni, Zn, Fe, Mn, Pb, As, and Sb were determined in sediment trap and bottom sediment samples collected seasonally from a station on the eastern Turkish coast of the Black Sea. Cd, Pb and Mn concentrations were highest in the sediment trap samples except during the summer period, whereas Co, Ni, Zn and Fe levels were much lower than corresponding levels found in the surface sediments. Cu, Cr, As and Sb levels showed no definite trend with sediment type. In general, with the exception of Cr, relatively lower metal concentrations in the sediment trap material were determined in the summer period. The highest mass flux, 56.5 g m−2 day−1, was measured during autumn. The highest flux of heavy metals also occurred during autumn and was strongly dependent on particle mass flux. Based on these results, we suggest that the downward vertical transport of particulate heavy metals in this region is related to the high degree of land erosion and the resultant particulate flux dynamics, which occur here. It was noteworthy that the highest concentrations of Cd, Cu, Co, Zn, Fe and Sb in particles were measured during winter a finding which suggests that enhanced fossil fuel combustion, which occurs during this period in adjacent urban and industrial areas plays an important role in the metal composition of sinking particles in nearshore waters.  相似文献   

15.
Sediment of variable mineralogical, textural and metal contaminant composition was collected from 38 estuaries along the Atlantic and Gulf of Mexico coasts of the United States and analyzed for total Al, Ag, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Si, Sn, Tl and Zn concentrations. Based on observed covariation of elements at 15 estuaries remote from contaminant inputs, linear regressions of metals on Al were used to model the metal content in baseline sediments. A geochemical model for the covariation was developed, verified and used to guide the statistical modelling approach. Comparison of metal concentrations predicted by the models with those occurring in uncontaminated geological materials suggests that baseline relationships are valid for the entire region sampled. Using these baseline relationships, sediment metal concentrations can be partitioned into natural and anthropogenic fractions. Models improve the comparability of metal levels in sediments by correcting for variable background concentrations that, if left uncorrected, only serve to increase total data variability and reduce detection of spatial and temporal differences.Examples of the application of baseline models to pollution studies are provided. A continuing decline in Pb concentrations in Mississippi River delta sediments is observed consistent with the declining use of Pb additives in gasoline since 1970. Major spatial trends in contaminant metals in sediments along the Atlantic and Gulf of Mexico coasts are noted.  相似文献   

16.
Abstract

Surface sediment samples (60 μm‐2 mm, and < 60 μm fractions) from the Waiwhetu Stream, Lower Hutt City, New Zealand, were leached with dilute HCl to remove the mobile heavy‐metal fraction. Cd, Cr, Cu, Pb, Zn, Al, Fe, and Mn analyses of the leachates show that sediments of the upper reaches area of the stream are generally uncontaminated. In contrast, sediments in the lower reaches area are highly contaminated, despite clean‐up measures in the late 1970s. Lead and Zn are the most significantly enriched metals with concentrations over 1000 mg kg?1 adjacent to some drains. In the polluted zone, metals originate from either upward remobilisation from underlying sediment (contaminated in the early 1960s and 70s) or more recent industrial spillages. Similar trends exhibited by Cd, Cu, Cr, Zn, Pb, and Al indicate that a proportion of the metal enrichment downstream probably results from a naturally higher clay content of sediments near the mouth of the stream. Fe and Mn show reverse trends to the other metals, indicating that a high proportion of these two metals occurs in substrate different to that of the other metals. The orange brick‐coloured sediments of the upper reaches of the stream indicate oxides upstream; the black sediments in the lower reaches indicate sulphides downstream.  相似文献   

17.
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   

18.
Metal concentrations in sediments and clams in four Moroccan estuaries   总被引：2，自引：0，他引：2  
Metals (Cd, Cu, Ni, Zn, Mn and Fe) were analyzed seasonally over three years in sediments and in tissues of the clam Scrobicularia plana in four Moroccan Atlantic estuaries: Loukkos, Sebou, Bou Regreg and Oum er Rbia. Of these metals, Cd was at the lowest concentrations in sediment. Concentrations of Cu, Zn, and to a lesser extent Ni, in sediments suggest greater contamination in Sebou and Bou Regreg than in the other estuaries. The fluctuations of Mn and Fe concentrations in the fine surface sediments reflect their continental origin and show seasonal variations that indicate soil run-off following rain events. Concentrations of Cu, Zn, and especially Ni in clam tissues in these estuaries were generally higher than in some other common bioindicator bivalve species. The seasonal variations in S. plana's tissue metal concentrations are linked to patterns of reproductive activity for all metals except Cd and possibly Zn, whose tissue concentrations may be regulated. Mn and Fe concentrations in S. plana were positively correlated to sediment levels of these metals.  相似文献   

19.
We examined metal (Al, V, Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb) and particulate organic carbon (OC) concentrations of the marine vertical export flux at the DYFAMED time-series station in the Northwestern Mediterranean Sea. We present here the first data set of natural and anthropogenic metals from sediment trap moorings deployed at 1000 m-depth between 2003 and 2007 at the DYFAMED site. A highly significant correlation was observed between most metal concentrations, whatever the nature and emission source of the metal. Cu, Zn and Cd exhibit different behaviors, presumably due to their high solubility and complexation with organic ligands. The observed difference of atmospheric and marine fluxes in terms of temporal variability and elemental concentration suggests that dense water convection and primary production and not atmospheric deposition control the marine vertical export flux. This argument is strengthened by the fact that significant Saharan dust events did not result in concomitant marine vertical export fluxes nor did they generate significant changes in metal concentrations of trapped particles.  相似文献   

20.
文章于杭州湾南岸潮滩布设3个采样断面并采集沉积物样本,采用地质累积指数法和潜在生态危害指数法评价重金属污染状况及其生态风险。研究结果表明:沉积物基本为粗粉砂和细砂,由海向陆粒径逐渐变细且分选性逐渐转差;所有站位重金属含量均值从高到低依次为Pb、Zn、Cu、Cr、Cd和Hg,断面重金属含量从高到低依次为高潮滩、中潮滩和低潮滩,Cu、Hg和Pb的空间分布差异较大;本次采样调查结果与邻近区域数据和同区域历史数据相比有所不同;根据地质累积指数评价结果,Cu、Pb和Zn有不同程度的污染;根据污染指数和潜在生态危害指数评价结果,Zn、Cd和Cr与地质累积指数评价结果区别较大,研究区重金属总体污染程度为低度和中度,除Cd外其他重金属处于低生态危害水平,研究区重金属总体生态危害为低度。调查和研究成果可为分析区域重金属环境影响和制定污染控制对策提供科学依据。  相似文献   

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