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1.
2.
The crab Carcinus maenas (L.) and the barnacle Elminius modestus Darwin were exposed to a range of dissolved concentrations of Zn, Cu and Cd for 21 days in artificial seawater. Accumulation of Zn and Cu by crabs has been interpreted in terms of the presence of a regulation mechanism to maintain constant body concentrations (83·2 ± 19·4 μg Zn g?1 dry wt.; 39·8 ± 9·8 μg Cu g?1 dry wt.) under varying external dissolved metal levels, until a threshold dissolved metal concentration (c. 400 μg Zn l?1; c. 170 μg Cu l?1) beyond which net accumulation of metal begins. Cadium appears to be accumulated by C. maenas at all exposures with no evidence for regulation of body cadmium concentrations. Exposure of E. modestus to Zn, Cu or Cd caused net accumulation of the respective metal in the bodies of the barnacles, with no evidence for regulation of body metal concentrations.  相似文献   

3.
- Five experiment ecosystems (MEEE) were employed in April, 1985 to test the effects of a mixture of Cu, Cd, Hg, Pb and Zn on a subtropical planktonic ecosystem in Xiamen Bay, Xiamen, China. The results indicated that the ppb-level of the mixture could suppress the planktonic production. Zooplankton in Xiamen were very sensitive to the metal contamination, especially the larvaceans.  相似文献   

4.
In order to identify the major sources of trace metals (TM) in the Portuguese coastal waters, 58 surface water samples were collected during September 1988. The area sampled extended from the Tagus Estuary (down to a salinity of 25) to cape Ste Marie on the southern coast of Portugal. Dissolved metal concentrations in the fully marine waters ranged from 30 to 250 pM for Cd, 0.7–15 nM for Cu, 0.9–20 nM for Zn and 1.8–4.5 nM for Ni. Within the Tagus Estuary (salinity 25), concentrations increased to 3400 pM for Cd, 26 nM for Cu, 14 nM for Ni and 230 nM for Zn.The large-scale distribution of these metals is dominated by two strong continental sources, both probably linked to the exploitation of pyrite ores. In the Tagus Estuary, TM enrichments can be mostly attributed to a pyrite roasting plant located on the shore in front of Lisbon. Concerning the south Portuguese shelf waters, several hypotheses are proposed to explain their elevated metal concentrations. We particularly discussed the likely influence of the Tinto/Odiel rivers located 100 km eastward, an influence well known in the shelf waters of the Gulf of Cadiz. These rivers are extremely metal-rich because of acid mine tailings originating from their catchment. Between these two regions, upwelling of relatively metal-poor water largely contributes to the dilution of the continental inputs. Indeed, water exchanges on the shelf linked to the upwelling involve water fluxes 500 times higher than the Tagus River flow, and renew the coastal waters that are thus cleaned from terrestrial contamination. Contrary to many other upwelling systems in non-contaminated areas, the Portuguese upwelling does not act as a source of trace-metal enrichment of the continental margin waters.  相似文献   

5.
厦门-金门海域表层沉积物中重金属铜铅锌镉的含量分布   总被引:7,自引:0,他引:7  
1995年 1 0月调查研究了厦门 金门海域表层沉积物中重金属Cu、Pb、Zn、Cd的含量 ,Cu、Pb、Zn、Cd的平均浓度分别为 1 6 .6、5 2 .6、1 0 4、0 .2 0 5 (× 1 0 -6m/m ,干重 )。根据底质标准 ,Pb、Zn明显超标。从平面分布看 ,厦门岛南部海区(XJ1~XJ4号站 )的重金属含量高于北部海区 (XJ5~XJ7号站 ) ,北部海区又高于东部海区 (XJ9、R1、R2号站 ) ,尤其是南部海区的XJ1、XJ2、XJ3号站其含量明显较高。这一分布特征表明除了九龙江河流对该海域的贡献外 ,西海域的输入也是一个重要的因素。位于东部海区的XJ9、R1、R2号站 ,从XJ9至较靠近金门的R1、R2号站 ,重金属Cu、Pb、Zn、Cd的含量略有回升 ,其来源有待于进一步分析探讨。  相似文献   

6.
The Bering Sea is an area of high biological productivity, with large populations of sea-birds, demersal and pelagic fishes, so it seemed desirable to assess the bioaccumulation of trace metals in the ...  相似文献   

7.
The understanding of the distribution of trace heavy metals in the world ocean has greatlyimProved in the past decades. But most of the data are of vertical profiles of certain stations(Bruland, l980; Paul et al., l992; RObert et al., l990) and large--scale study of temporaland spatial variability of trace heaVy metals in the ocean is rather few. In fact, affected by ver-tical mixing by upwelling or convection, biogenic removal, atmospheric fallout and continentalinput frorn rivers, the dist…  相似文献   

8.
南海表层水中的溶解态Cu,Pb, Zn,Cd   总被引:9,自引:0,他引:9  
于1998年“南海海洋环境调查”外业工作期间在南海的各个站位,按照严格的防沾污措施采集了106个表层海水样品.采用溶剂萃取-石墨炉原子吸收法对样品中的痕量重金属Cu,Pb,Zn,Cd含量进行了分析测试.测得各重金属的平均值如下:Cu 0.100 μg/dm3,Pb 0.060μg/dm3,Zn 0.086 μg/dm3,Cd 0.007μg/dm3,接近世界大洋水的浓度水平.各重金属的空间分布呈现出海区周边含量高于中央,浓度有自近岸向远海逐渐减小的趋势.相关分析的结果表明各重金属夏季相关性优于冬季,Cu与Cd存在良好的正相关关系,并且首次在南海表层水发现Cu,Cd与营养盐的相关关系.将重金属浓度值作数理统计分析,得到它们在南海的基线值.  相似文献   

9.
In this paper, the samples of sediments collected from five sampling-stations in the river-sea water mixing zone of the Zhujiang Estuary have been determined by the sequencial extraction procedure, anodic stripping voltammetry and atomic emission spectrometry etc. The contents of the heavy metals Zn, Cu, Pb and Cd in the various phases which are dissolvable, ion-exchangeable, combined with carbonates, easily-reducible, reducible, combined with organic matters and sulfides and residue in the sediments, have been obtained.  相似文献   

10.
The resuspension of 65 marine sediments was simulated in the laboratory with elutriates from 30 different sites from the north coast of Spain. The partitioning of Cu, Pb and Zn between sediment and elutriate was studied as a function of different physicochemical characteristics of the sediment: organic matter (OM), fine fraction (FF), redox potential and acid volatile sulfides (AVS). Mean remobilization factors (RF) -calculated as metal concentration in the elutriate (μg/L) divided by metal concentration in the sediment (μg/g dry weight)- were 0.072 for Cu, 0.012 for Pb and 0.071 for Zn. Remobilization of Pb was significantly lower than that of Cu and Zn. Although AVS, OM and FF presented a strong intercorrelation, OM explained great part of the variability on Cu and Pb remobilization while AVS did it for Zn. A multiple regression model considering both OM and AVS explained slightly better the remobilization of Pb and Cu, but not that of Zn.  相似文献   

11.
重金属对扁额细首纽虫金属硫蛋白的影响   总被引:1,自引:0,他引:1  
生物体内金属硫蛋白含量变化,可作为环境中重金属污染的生物标志物.通过暴露实验研究了扁额细首纽虫Cephalothrix simula暴露在不同浓度的铜,锌和镉溶液96 h,其体内金属硫蛋白含量的变化规律.结果表明3种重金属离子的胁迫作用均导致金属硫蛋白含量增加,在实验初期(6~24 h),金属硫蛋白含量达到高峰;金属硫蛋白含量与暴露溶液金属浓度具有明显的剂量~效应关系,金属离子浓度越高,金属硫蛋白含量越高;锌离子诱导金属硫蛋白合成的作用大于铜、镉离子.  相似文献   

12.
董炜峰  苏荣 《海洋通报》2007,26(2):96-99
参考《海洋监测规范第6部分:生物体分析》(GB17378.6-1998)的规范方法,采用单一HNO3-HClO4常压方法消化贻贝成分分析分析标准物质(GBW08571)。取样量为0.500g时,在加热温度为160℃~210℃,加入10mL HNO3、2mLHClO4,加盖加热7h左右,最后的样品消化液赶酸赶净的条件下,样品消化液直接以原子吸收分光光度计测定,其中Cu,Pb,Zn,Cd,Cr的测定值都在标准值范围之内。并着重对比温度对消化效果的影响以及Cu,Cd以火焰法与无火焰法测定的差别。  相似文献   

13.
Cd, Cu, Fe, Ni, Pb and Zn were determined in 123 samples from the Baltic Sea proper. The trace metals were extracted directly on board the vessel, using a dithiocarbamate-Freon procedure. Final analyses of the extracts are performed onshore by atomic absorption spectrometry.Similar trace-metal concentrations are found in different areas of the Baltic proper. Most values fall in the following ranges: Cd, 30–60 ng 1?1; Cu, 0.6–1.0 μg 1?1; Fe, 0.3–0.9 μg 1?1; Ni, 0.6–0.9 μg 1?1; Pb, 0.05–0.2 μg 1?1; and Zn, 1.5–3.5 μg 1?1. The metal-concentrations are generally independent of depth. However, copper exhibits a small but significent decrease in concentration below 80 m.Filtration did not affect trace-metal concentrations, with the exception of iron in waters from lower layers. Similarly, storage under acid conditions was shown to affect only the concentration of iron. An electro-chemical technique was also used to determine Cu in some samples.  相似文献   

14.
A simple and rapid method has been proposed for direct determination of Cd, Pb, Cu in marine sediments and suspended matters by graphite furnace atomic absorption spectrometry, using the HNO_3-HClO_4-HF decomposition. The L'vov platform and matrix modiffer technique were used with peak-area measurement to effectively eliminate the matrix  相似文献   

15.
This paper suggests direct and simultaneous determinations of the reducible species of Zn, Cd, Pb, Cu and Bi in seawater made by the derivative-differential pulse anodic stripping voltammetry with a hung mercury drop electrode. The influence of Cu on the determination of Zn in this experiment condition has been studied, of which both the accuracy and precision are satisfactory. The procedure of determination is so quick, simple and convenient that the background concentration of these five elements in coastal seawaters can be determined only by adjusting the acidity of seawater to pH 2.5 and by taking 10-minutes plating time. Actual measurement time of these five elements for every sample is approximately 25 min.  相似文献   

16.
图们江口水中Zn,Cd,Pb,Cu的形式分析   总被引:1,自引:0,他引:1  
本文用防吸附物理涂汞电极反问极谱对图们江口、东海及日本海水中Zn,Cd,Pb,Cu进行了形式分析,其不稳定态的平均浓度分别为5.9,0.071,0.039,0.69ug/L(占总量的15~27%),分布较为均匀,证实了痕量金属离子(自由离子及不稳定络离子的均匀分布规律。有机结合态Zn,Cd及Pb(10~30%)和颗粒态Zn,Cu和Cu(15~40%)的较高含量位于长江口、东海及图们江口。  相似文献   

17.
The short-term (5 day) accumulation of Cu and Zn in different tissues of the marine gastropod, Littorina littorea, has been studied in the presence of 10 mg l−1 of antifouling paint particles and pre- or simultaneously contaminated algal food (Ulva lactuca). Accumulation of Cu was observed in the head–foot, digestive gland–gonad complex and gills to extents dependent on how and when food was contaminated and administered. However, retention of Zn was only observed in the gills and only when L. littorea and U. lactuca were simultaneously exposed to paint particles. Relative to the alga, faecal material was highly enriched in Zn, suggesting that the animal is able to rapidly eliminate this metal, most likely through the formation and egestion of insoluble phosphate granules. Thus, L. littorea is a useful biomonitor of marine contamination by antifouling applications in respect of Cu but not Zn.  相似文献   

18.
In June 1981, dissolved Zn, Cd, Cu, Ni, Co, Fe, and Mn were determined from two detailed profiles in anoxic Baltic waters (with extra data for Fe and Mn from August 1979). Dramatic changes across the O2H2S interface occur in the abundances of Cu, Co, Fe, and Mn (by factors of ?100). The concentrations of Zn, Cd, and Ni at the redox front decrease by factors between 3 to 5.Equilibrium calculations are presented for varying concentrations of hydrogen sulfide and compared with the field data. The study strongly supports the assumption that the solubility of Zn, Cd, Cu, and Ni is greatly enhanced and controlled by the formation of bisulfide and(or) polysulfide complexes. Differences between predicted and measured concentrations of these elements are mainly evident at lower ΣH2S concentrations.Cobalt proved to be very mobile in anoxic regions, and the results indicate that the concentrations are limited by CoS precipitation. The iron (Fe2+) and manganese (Mn2+) distribution in sulfide-containing waters is controlled by total flux from sediment-water interfaces rather than by equilibrium concentrations of their solid phases (FeS and MnCO3). The concentrations of these metals are therefore expected to increase with prolonged stagnation periods in the basin.  相似文献   

19.
The forms distribution of Zn, Cd, Pb and Cu in waters of the Northwest Bohai Gulf is investigated by inverse polarography of anti-adsorption physically coated mercury film electrode, the higher content of most forms of trace metals is in polluted estuary water, and unstable Zn and Pb are in anomalous distribution. The average concentrations read ΣZn 20.0μg/1 (14.5-36.6 μg/l, ΣCd 0.11pg/1 (0.080-0.14μg/1), ΣPb 1.0μg/1 (0.58-1.6 μg/1), and ΣCu 5.2μg/1) (2.37-8.43 μ/1) respectively.  相似文献   

20.
In many aquatic organisms including Mytilus edulis, the role of temperature on bioaccumulation of metals is still not clearly understood. In this study, uptake and accumulation of Cu, Co, Cd and Pb in mussels were investigated at different temperatures (6-26 degrees C). Results from exposure of isolated gills showed a positive relationship between temperature and metal uptake. But in whole organism experiments, only the accumulations of non-essential metals (Cd, Pb) showed a similar trend while the two essential metals Co and Cu were independent and inversely related to temperature, respectively. With exception of Cu, elimination process appeared to be independent of temperature. The study also showed that neither changes in scope for growth (SFG) of mussels nor chemical speciation could fully account for the observed temperature-effects. Overall, these results suggest that fundamentally (i.e. at epithelial membranes), temperature-effects on uptake are largely due to changes in solution chemistry and physical kinetics, which favours higher uptake at high temperature. But at whole organism level, complex physiological responses appears to mask the relationship, particularly for biologically essential metals like copper.  相似文献   

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