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1.
The spatial distribution of selected metals (Fe, Ni, Mn, Zn, Cu, Pb, Hg and Cd) and their partition in the different chemical forms (speciation) were determined in benthic sediments from Mar Piccolo, Taranto (Ionic Sea, southern Italy). The aim of this study was to assess the degree of sediment contamination and bioavailability of metals, very important for Italian mussel culture, in a semi-enclosed marine ecosystem. In sediments, grain size distribution, total organic carbon (TOC), and humic (HA) and fulvic (FA) acids contents were also determined. The compounds TOC, HA and FA, in fact, have a great influence on metal complexation. High concentrations of copper, lead, zinc and mercury were found, especially in sediments of the first inlet of Mar Piccolo. Statistical analysis of results shows significant correlation among Cu, Pb and Zn concentrations and the influence of organic matter on the sediment distribution of Cu, Pb and Zn. Metal speciation analysis, carried out with sequential extraction method, shows that Fe and Ni are present in sediments mainly as sulphides. Mn and Pb are present principally in an ion-exchangeable form or bound to carbonate and Cu is associated to organic matter. Metal pollution index (MPI), calculated as a weighed mean of the metal contamination factors in each station, shows that with regard to Cu, Ni, Pb and Zn, some stations investigated are unpolluted (MPI <1), whereas in other areas, pollution level is not very high. On the contrary, for mercury, the pollution level in the first inlet of the basin is very high.  相似文献   

2.
Distributions of heavy metals in the sediments of South Korean harbors   总被引:1,自引:0,他引:1  
Bottom sediments of harbors in the South Korea have been long suspected for metal contamination due to ship-based and urban-based activities for the past several decades. A number of areas have been suspected to impair ecosystem services to the local residents and drawn complaints from main stakeholders. Twelve contamination suspected harbors were subject to evaluate the level of contamination of Cr, Ni, Cu, Zn, As, Cd, Pb and Hg. The level of sediment contamination for each metal was evaluated comparing the relative enrichment of a given metal to pollution-insensitive aluminum. Regional background concentration of a given metal was also determined based on its down core measurement and sediment texture. Ecological risk posed by the presence of heavy metals was evaluated using the sediment quality guidelines (SQGs) developed by United States National Ocean and Atmosphere Administration (US NOAA) as benchmarks for evaluating sediment chemistry to aquatic organisms. Cu, Zn, Cd, Pb and Hg in the surface sediment were found to be higher than a factor of 1.5 than background sediments, and the overall metal contaminations of surface sediment can be regarded as medium-high- to high-priority sites in the sense of SQGs.  相似文献   

3.
Bottom sediments of harbors in the South Korea have been long suspected for metal contamination due to ship-based and urban-based activities for the past several decades. A number of areas have been suspected to impair ecosystem services to the local residents and drawn complaints from main stakeholders. Twelve contamination suspected harbors were subject to evaluate the level of contamination of Cr, Ni, Cu, Zn, As, Cd, Pb and Hg. The level of sediment contamination for each metal was evaluated comparing the relative enrichment of a given metal to pollution-insensitive aluminum. Regional background concentration of a given metal was also determined based on its down core measurement and sediment texture. Ecological risk posed by the presence of heavy metals was evaluated using the sediment quality guidelines (SQGs) developed by United States National Ocean and Atmosphere Administration (US NOAA) as benchmarks for evaluating sediment chemistry to aquatic organisms. Cu, Zn, Cd, Pb and Hg in the surface sediment were found to be higher than a factor of 1.5 than background sediments, and the overall metal contaminations of surface sediment can be regarded as medium–high- to high-priority sites in the sense of SQGs.  相似文献   

4.
There is a recognised need to integrate multiple toxicity data deriving from battery bioassays into an easily understandable and single value, which may facilitate the decision-making process related to the management of contaminated sediments. In this study, two integration results systems were applied and compared: toxicity classification system (TCS) and Toxicity Test Battery integrated Index (TBI). The quality of sediments of the Taranto seas (Mar Grande and Mar Piccolo) was assessed by a battery of five test species representing different trophic levels (Dunaliella tertiolecta, Tigriopus fulvus, Corophium insidiosum, Mytilus galloprovincialis, and Anphibalanus amphitrite) and performed on three exposure phases (elutriate, porewater, and whole sediment). The integration of biological tests results with TBI showed that stations located in Mar Grande and one station in Mar Piccolo were in the high ecotoxicological risk level, according to the results obtained with TCS. The comparison of results deriving from two evaluation systems showed similarity in the ecotoxicological risk level. Only in one case there was a lack of concordance between two indices giving opposite judgments. The present study demonstrates that the use of one of the two indices can be useful to estimate and to rank hazard level for sediments.  相似文献   

5.
Heavy-metal concentrations were measured in sediments and tissues of Posidonia oceanica seagrass from south-eastern Sicily (Italy) in order to assess the degree of metal pollution in the coastal area. Seagrasses and sediments were collected at four sites along the south-eastern coast of Sicily. Flame atomic absorption spectrophotometry (FAAS) was used to measure concentrations of Cu, Zn, Cd and Pb. Standard statistical analyses were used to assess significant differences among the levels of the elements measured in different tissues and sediment and spatial distribution. The greatest values of potentially toxic metal concentrations were observed at the station near the industrial sites of Augusta and Priolo. Comparisons with the concentrations of the same metals in other sites of north and western Sicily and with data from surveys in other areas of the Mediterranean Sea are shown.  相似文献   

6.
The aim of this study is to determine the contents of aluminum, iron, manganese, nickel, copper, zinc, chromium, cadmium, lead, and mercury in sediments at 1–30?m depths of the Band?rma and Erdek Gulfs in the Southern Inner Shelf of the Marmara Sea. Sediment samples were collected from different depths (1?m, 5?m, 10?m, 20?m, 30?m) at each region in February 2008. Primary hydrographic conditions, such as temperature (6.6–14.5°C), salinity (22.6–26.875 psu), percentage of dissolved oxygen saturation (35–83 %), and pH (8.0–8.4) were recorded for each sampling point. Moreover the total organic carbon (0.5–2.9%) and the total calcium carbonate contents (0.8–60%) of sediment samples were determined. In surface sediments of both gulfs, Pb (21–62?mg?kg?1) and Cd (0.52–0.86?mg?kg?1) contents were determined to be higher than the shale average (Pb 20?mg?kg?1, Cd 0.2?mg?kg?1) while the other metal contents were measured to be lower in general. On the other hand, generally Hg (0.06–1.1?mg?kg?1) contents were higher than the shale average (0.3?mg?kg?1)at all of the examined stations in the Band?rma Gulf and lower than the shale average in the Erdek Gulf.  相似文献   

7.
Concentration of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Pb, Se and Zn were determined in various fish species from the Marmara and Black Sea during 1987 and 1988. Neutron activation analysis, atomic absorption spectrophotometry and X‐ray fluorescence methods were used for analysis. No significant differences between metal values in fish collected in 1987 and 1988 were noted except As and Pb. The As and Pb concentrations in the same species of fish were higher in the eastern Black Sea compared with the other locations. The Hg concentration in Thunnus thynnus muscle ranged from 1.05–3.05 μg/g dry weight. On the other hand, the Hg levels in the other species were found below the detection limit. Comparison of the results obtained with data reported for the Mediterranean Sea shows an agreement in general for most of the metal levels.  相似文献   

8.
Amongst a plethora of threats to seagrass ecosystems, contamination with heavy metals may well be one of the most significant. We therefore set out to track contamination levels with Cu, Zn, Pb and Cd in the principal autotrophic compartments and sediments of a meadow of Posidonia oceanica in the Gulf of Naples, Mediterranean Sea. With respect to metal levels, leaves and their associated epibiota are certainly not a homogenous compartment, as might perhaps be inferred from the common use of the term “leaf–epiphyte complex” in the literature. Save for Cu, all metal species analysed showed appreciable differences in concentration between seagrass leaves and epibiota. These results give strength to our argument that in ecotoxicological work leaves and epibiota should not be treated as a single unit. Although absolute differences in trace-metal levels among sampling periods varied somewhat with the specific component analysed (i.e. macrophyte organs, epibiota, sediment), an overall trend of markedly higher heavy-metal levels during the winter season is a striking one. Whilst annual cycles in growth dynamics of the seagrasses explain a significant fraction of the temporal variance, seasonality in productivity is a doubtful explanation for similar patterns in non-living sedimentary components; consideration of additional variables therefore seems sensible. As variables with consistent explanatory powers we suggest: (1) seasonal cycles in storm frequency and amplitude which remobilise metals bound in the sediments of the sea floor, and (2) increased precipitation during the cold season which may significantly increase marine metal levels through elevated weathering of rocks and elevated fluvial inputs of anthropogenic contaminant loads. Whereas Cd and Pb concentrations in seagrass leaves from the Gulf of Naples fall within the range for coastal areas subjected to low levels of heavy-metal pollution, Cu and Zn reach levels typical of highly contaminated regions, such as the waters bordering major coastal cities. Any direct comparisons of the pollution status of seagrass beds between different geographic areas are, however, likely to be confounded by the indiscriminate application of the “leaf–epiphyte complex”: the magnitude of the confounding effect depends on the ratio of epibiota/leave biomass, time of sampling, and metal species analysed. Received: 15 May 1997 / Accepted: 2 February 1998  相似文献   

9.
This article presents results on heavy metal (Fe, Mn, Cr, Ni, Cu, Cd, Pb and Zn) speciation in the coastal sediments of Albania. Sediment samples were collected within the framework of the activities of the Interreg Italia–Albania Project, carried out in the Southern Adriatic Sea in 2000–01. This study shows that Albanian coastal sediments are highly influenced by river input, as the decreasing concentrations from coast to offshore confirm. Pb represents an exception of the general trend; meteoric inputs are prevalent for this metal. Ni, Cr, Fe, Zn and Cu correlate significantly and positively in the entire area, indicating a common origin for these metals in the analyzed sediments. All metals result mostly associated to the most refractory phases, which constitute up to 80% of the total concentration. Nevertheless a recent input of Cr, Ni, Cu and Mn can be observed, as the result of mining and industrial activities, in some selected areas, such as the Drin Bay and Durres. Their high concentration in the bioavailable phase can determine toxic effect upon biota.  相似文献   

10.

The paper reports heavy metal accumulation in algae collected at four stations and in sediments at three stations on the Black Sea coast of Turkey. The metals analysed are Cd, Co, Cr, Cu, Fe, Pb, Sb and Zn. The metal content of algae increased generally (with some exceptions) from 1991 till 1993 in ?ile and Sinop. In the sediments Sb in ?ile, As in Riva, Fe, Zn in Sinop are high. According to these findings the metal pollution increased in Turkish area of the Black Sea during the years investigated.  相似文献   

11.
The barnacle Balanus improvisus and the mussel Mytilus trossulus have been used as biomonitors of the trace metals Cu, Zn, Cd, Fe, Pb, Mn and Ni at five sublittoral sites in the Gulf of Gdansk (Baltic Sea) between February 2000 and September 2001. The study has established a benchmark against which future biomonitoring programmes will be able to establish changes in local metal pollution, particularly if metal loadings in the river Vistula (draining into the Gulf) alter in the future. The study highlighted differences in trace metal bioavailabilities to both barnacles and mussels, geographically and over time. Accumulated metal concentrations of Cu, Zn, Fe, Pb and Ni, but not Cd or Mn, were correlated in the barnacles and mussels, suggesting that the bioavailabilities of the former metals to the two biomonitors were similar. The barnacles showed greater discriminatory power than the mussels as trace metal biomonitors. Concentrations of trace metals in surficial sediments (<63 m) did not correlate significantly with accumulated metal concentrations in either barnacles or mussels, indicating that sediment metal concentrations are not necessarily good proxy measures of ambient trace metal bioavailabilities to the local coastal filter feeders.Communicated by J.P. Thorpe, Port Erin  相似文献   

12.
Methylation experiments of the metals Sn, Pb and Hg were carried out using representative terrestrial and marine sediment samples from the Axios river and Thermaikos Gulf in northern Greece. GC-FID, GC-TCD and GC-MS were used. The experiments were carried out on sterilised and bioactive samples by adding pure metals and metal salts (chloride, nitrate, oxalate, acetic, penicillaminic, methioninic and cysteinic). Except for sterilised HgCl2, methylated derivatives of Sn, Pb and Hg were produced only from bioactive sediments, and therefore higher yields were measured when nutrients were added to the sediments. Volatile products (CH4, CO2, H2S) of biological activity range between 35 and 250 mg l-. The correlation of methylation yield with organic sediment index (OSI), determined as the wt% product of [organic carbon] × [organic nitrogen], is positive for all the metals and metal salts added in the sediments. Methylation yields for Hg are found to be four orders of magnitude higher than those of Pb and Sn. In low OSI (terrestrial) sediments, the rate of Hg-methylation is higher than those of Pb and Sn. In high OSI (marine) sediments, where methylation of most of the contained Hg has taken place, methylation of Pb is slightly faster than Sn.  相似文献   

13.
利用地理信息系统(GIS)和地统计分析方法对宝山区农业用地土壤重金属(As,Cd,Cr,Hg,Pb)空间分异规律和分布特征进行研究.结果表明,区内农业用地土壤中5种重金属均表现为中等空间变异性;在全局趋势上,Cd为一次全局趋势,其余重金属元素都表现为二次趋势;5种元素在空间上均存在明显的方向效应;Cr,Hg和Pb具有强烈的空间相关性,As和Cd具有中等强度的空间相关性;5种重金属的空间变程由大到小分别为Hg,Pb,Cr,As和Cd.土壤重金属As,Cd,Cr,Hg和Pb平均含量分别为7.31mg.kg-1、0.24 mg.kg-1、107.89 mg.kg-1、0.15 mg.kg-1和38.54 mg.kg-1,分别是上海土壤背景值的0.80,1.81,1.44,1.43和1.51倍.宝山区南部农业用地土壤重金属污染程度普遍高于北部.从宝山区各镇农业用地土壤重金属污染看,Cr和Pb普遍污染严重,而基本不存在As污染.同期降尘污染调查表明,降尘重金属是本区土壤重金属污染的最重要来源.  相似文献   

14.
尽管针对洞庭湖沉积物中重金属的研究工作较多,但缺乏针对其主要入湖口的研究。基于2014年12月和2015年6月对洞庭湖主要入湖口表层沉积物中重金属调查,分析了重金属含量的时空分布特征,并采用一致性沉积物质量基准法对其生态风险进行了评价。结果表明,Cd、Hg、As、Cu、Pb和Zn的平均含量分别为3.27、0.190、27.10、39.8、38.0和157.8 mg·kg-1,其大小顺序为ZnCuPbAsCdHg,Cd和As含量出现超过土壤环境质量三级标准的现象,是主要的重金属污染物。Cd、As、Pb和Zn等4种重金属含量的最高值均出现在湘江入湖口,Cu含量的最高值出现在资水入湖口,Hg含量以沅江入湖口最高,除Pb外,其他5种重金属在湘江和资水入湖口的含量均大于平均值,表明湘江和资水入湖口污染较为严重;汛期与非汛期6种重金属的含量均无显著性差异(P0.05)。6种重金属生态风险大小顺序为AsCdZnPbCuHg,各入湖口生态风险大小顺序为湘江入湖口资水入湖口沅江入湖口汨罗江入湖口澧水入湖口长江"三口"新墙河入湖口,其中湘江和资水入湖口为较高生态风险,其他入湖口为较低生态风险。入湖河流是洞庭湖湖体沉积物重金属污染的主要来源,在一定程度上,入湖河流沉积物中重金属的含量对洞庭湖湖体沉积物中重金属污染状况起着决定性作用,因此,洞庭湖流域重金属污染防控应以入湖河流为主,其中尤以湘江和资水为重点。  相似文献   

15.
To assess the natural and anthropogenic radiocontamination, sediment samples were collected in the Tigullio Gulf (Ligurian Sea). the results presented here indicate a significant Cs-137 contamination (about 20 Bqkg-1 dry weight) while concentrations of “primordial” natural radioisotopes were similar to those detected in other coastal areas. Gross sedimentation rates, determined through measurements of Be-7 concentrations, were at about 4-5 cm in the last 6 months. Natural and artificial radioactivity concentrations have been compared with data obtained in other Mediterranean areas. Heavy metals (Cu, Cr, Mn, Ni, Zn, Pb, Cd, Hg) concentrations were also determined inside the bay. Most elements displayed quite constant concentrations through the sediment core, except for copper which had showed highest concentrations in the top 16 cm of the sediment.  相似文献   

16.
深圳市内某河表层沉积物重金属含量及污染评价   总被引:2,自引:0,他引:2  
2008年11月,从广东省深圳市内某河采集9个(0—5cm)表层沉积物样品,分析其Cu,Cd,Cr,Pb,Zn,Ni,As和Hg的含量和前6种元素的形态分布,并采用潜在生态风险指数法进行污染评价.结果表明,沉积物中Cu和Zn的含量普遍较高,为5.27—1865mg.kg-1和198.4—1275mg.kg-1,其次是Cr,Ni和Pb,为54.39—908.7mg.kg-1、31.3—445.5mg.kg-1和11.63—814.9mg.kg-1,As,Cd和Hg的含量较少;Cd的残余晶格态、Cr的铁/锰氧化态和残余晶格态、Cu的有机结合态和残余晶格态,以及Ni,Pb和Zn的铁/锰氧化态为各元素的主要存在形态;沉积物中Cd和Cu的潜在生态风险普遍较大,9个样品中6个达到Cd极强生态危害,4个达到Cu很强生态危害,有5个样品的重金属混合污染潜在生态风险达到极强生态危害.  相似文献   

17.
Rieselfelder     
Soils of the large sewage farm area south of Berlin are contaminated with heavy metals such as Cd, Cr, Cu, Hg, Ni, Pb, Zn. Based on earlier studies the total amount and the bioavailable proportions of heavy metals in soil samples were analysed. In some samples very high levels of total heavy metal concentrations were detected. For Pb, Cd, Cu and Hg the maximum values were 1360, 29.7, 817 and 40.8 mg/kg soil dry matter, respectively. The biovailable fractions of heavy metals which were found primarily in the acetate and EDTA fractions and to a lesser degree in the water extract account for about 50 % (Pb, Ni), 70 % (Cd) or 90% (Zn) of their total amount and may therefore pose a considerable environmental risk.  相似文献   

18.
利用物种敏感性分布(species sensitivity distribution,SSD)方法构建常见重金属元素对海洋生物的SSD曲线,在此基础上,结合实际调查数据,计算了中国近海7种重金属(As、Cd、Cr、Cu、Hg、Pb、Zn)和福建主要海湾6种重金属(As、Cd、Cu、Hg、Pb、Zn)对海洋生物的潜在影响比例(PAF),并分析了各种重金属在相应海区的联合生态风险(msPAF)。结果表明,中国近海水体重金属对海洋生物的生态风险大小顺序为:渤海(20.67%)>黄海(18.39%)>东海(15.94%)>南海(11.26%)。福建主要海湾水体重金属对海洋生物的生态风险大小顺序为:泉州湾(47.44%)>厦门湾(47.16%)>罗源湾(43.03%)>沙埕港(34.65%)>深沪湾(30.34%)>三沙湾(28.64%)>闽江口(20.55%)>诏安湾(20.42%)>兴化湾(18.37%)>湄洲湾(17.24%)。  相似文献   

19.
Concentrations of ten metals (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg) in the edible muscle of Arius maculatus captured from eight different near‐shore and off‐shore sites off the south west coast of the Arabian Sea, Pakistan, were determined by atomic absorption spectrophotometry. Relevant water and sediment samples from the sites were also analysed for the metals. Zinc showed the highest metal concentration (6.763 μg/g, wet weight) in the muscle of the fish, while Mn and Hg showed lowest level (0.019 μg/g, wet weight). Of all the metals investigated, largest scatter (measured as σ) was observed for Zn = 2.058 /μg/g) in fish muscle, for Fe and Mn in sediment (σ = 27481 and 44.50 μg/g) and for As in water (σ = 0.270 μg/L). The metal distribution data pertaining to water, fish and sediment were examined on the basis of simple metal correlations. The statistical study revealed that Ni, Cr, Pb and Cu had significant positive correlations (r > 0.830 at ρ = 0.01). The finding substantiated a trace metal concentration gradient in the area, thereby indicating that the local marine environment is contaminated by anthropogenic sources.  相似文献   

20.
Data on Cd, Pb and Cu concentrations in seawater referring to five years of field studies on the western Mediterranean Sea are reported in order to present a space and time integrated situation on the levels of these metals. Surface total metal concentrations present rather homogeneous distributions between the different areas considered, including the Tyrrhenian Sea. The metal concentrations in three areas affected by natural and industrial wastes are also discussed. The vertical distribution of the dissolved Cd, Pb and Cu in the Alboran Sea seems to be rather homogeneous, both vertically and among the stations chosen between the Strait of Gibraltar and the Island of Alboran.  相似文献   

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