Natural and anthropogenic sources of Hg,Cd, Pb,Cu and Zn in seawater and sediment of Mljet National Park,Croatia

Distributions of Hg, Cd, Pb, Cu and Zn in seawater and sediment from Mljet National Park, Adriatic Sea are presented for the first time. Natural and anthropogenic factors play an important role in determining resultant trace metals' concentrations in the region. We place particular emphasis on the saline “lakes” of Malo Jezero and Veliko Jezero, which have restricted flows of seawater. In Malo Jezero lake, fresh karstic spring water generated by flooding, and weathering of dolomites are the main sources of naturally elevated Cd, Pb and Zn concentrations (20.7 ± 1.6, 289 ± 19, 1260 ± 0.08 ng L^?1, respectively); anthropogenic input is negligible. In Veliko Jezero lake enhanced Cu and Zn contents originate from anthropogenic input (tourism and agriculture). Distributions of the Pb and Zn in the water columns of both lakes are influenced by natural aragonite precipitation and sedimentation. Exceptionally high total Hg concentrations of 24.2 and 33.7 ng L^?1 in the water column of Malo Jezero, sampled during periods of high rainfall associated with strong eastern winds, suggest an airborne input. Total Hg concentrations in waters of both lakes are elevated because of inefficient mixing. Two different metal distribution patterns exist in the sediment columns. First, Hg, Pb, Cu and Zn show elevated concentrations in recent sediments due to anthropogenic input. Second, Cd content increases with depth due to reprecipitation via a downward redox boundary shift.Described natural processes, as well as anthropogenic influence, enhance levels of trace metals. Careful study followed by suitable interpretation based on geochemical data were necessary to distinguish natural from anthropogenic sources.     

Dissolved Cu, Pb, Zn and Cd in the South China Sea surface waters

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…     

南海表层水中的溶解态Cu,Pb, Zn,Cd

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.     

Distribution and stoichiometry of Al,Mn, Fe,Co, Ni,Cu, Zn,Cd, and Pb in seawater around the Juan de Fuca Ridge

A central theme of the ongoing GEOTRACES program is to improve the understanding of processes occurring at ocean interfaces with continents, sediments, and ocean crust. In this context, we studied the distributions of Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb around the Juan de Fuca Ridge (JdFR) in total dissolvable (td), dissolved (d), and labile particulate (lp) fractions, which represent a fraction in unfiltered samples, filtered samples through an AcroPak capsule filter, and the difference between td and d, respectively. Al and Fe were dominated by lp-species, while Ni, Zn, and Cd were dominated by d-species with undetectable amounts of lp-species. Major findings in this study are as follows: (1) The continental margin (CM) provided large sources of Al, Mn, Fe, and Co from the surface to ~2000 m in depth. The supply from CM caused high surface concentrations of dMn and dCo, a subsurface (100–300 m depth) maximum of dCo, and intermediate (500–2000 m depth) maxima of lpAl and lpFe. The supply of dFe from CM was ~10 times that from the high-temperature hydrothermal activity at station BD21, which is located at ~3 km from the Middle Valley venting site and ~ 200 km from Vancouver Island. (2) DPb was maximum at the top layer of North Pacific Intermediate Water, probably owing to isopycnal transport of anthropogenic Pb via advection of subducted surface waters. Although dCo and dPb had different sources in the upper water, they showed a strong linearity below 300 m (r ² = 0.95, n = 38), indicating concurrent scavenging. (3) A high-temperature hydrothermal plume occurred at a depth of 2300 m at BD21, accounting for maxima of dAl, dMn, dFe, lpCu, and lpPb and a minimum of dCu. (4) Strong bottom maxima of lpAl, lpMn, lpFe, lpCo, and lpPb occurred above the abyssal plain at the western foot of the JdFR, indicating resuspension of sediments. However, bottom maxima of d-species were apparent only for dAl and dCu.     

The distribution of Mn,Fe, Zn,Cd and Cu in Baltic seawater; a study on the basis of one anchor station

A total of 150 samples were collected at a 10-days' anchor station in the Bornholm basin (55° 31.1′N, 15° 32.1′E) and analyzed for dissolved (< 0.4 μm) and particulate trace metals. For dissolved Mn, large gradients have been found in the vertical distribution with minimum concentrations (< 0.2 μgl^?1) in the halocline zone and considerably higher values in the deep waters (up to 50 μgl^?1). Ultrafiltration studies indicate that dissolved Mn is probably present as Mn²⁺ in the oxygenated bottom layer. The primary production process was not evident in the particulate Mn profile; the suspended particulate material (SPM), however, shows a considerable enrichment with depth, apparently due to Mn-oxide precipitation.The distribution of dissolved Fe was rather homogeneous, with average concentrations throughout the water column between 0.86 and 1.1 μgl^?1, indicating that the oxidation of Fe²⁺ ions released from the sediments must already be complete in the very near oxidation boundary layer. Relatively high concentrations of particulate Fe were actually measured in the bottom layer, with the maximum mean of 11.2 μgl^?1 at 72 m. Similarly to Mn, the profile of particulate Fe does not reflect the SPM curve of the eutrophic layer. On average, about 70% of the total Fe in surface waters was found to be particulate.The average concentrations of dissolved Zn, Cd and Cu were found to be rather homogeneous in the water column but showed a relatively high variability with time. A simplified model on trace-metal uptake by phytoplankton indicates no significant change in dissolved metal concentrations during the period of investigation. On average, only 1.7% Zn, 3.3% Cd and 9.8% Cu of the total metal concentrations were found in particulate form. SPM analyses showed significant correlations of Zn, Cd and Cu with Fe, indicating that particulate iron is an important carrier for particulate trace metals in Baltic waters.     

The determination of Cd,Cu, Fe,Ni, Pb and Zn in Baltic Sea water

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.     

HNO3-HClO4-原子吸收分光光度法测定海洋生物体中Cu,Pb,Zn,Cd,Cr

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。     

Zn, Pb, Cu AND Cd IN PHASES OF SEDIMENTS IN ZHUJIANG ESTUARY

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.     

A sample changer for automated seawater nutrient analysis systems

An automatic sample changer based upon a commercially available 20-port rotary valve has been developed for use in automated seawater nutrient analyses. All parts exposed to seawater are of stainless steel, Teflon®, or Kel-F®. The sampler has proven to be rugged and efficient in both shore and shipboard laboratories.     

厦门-金门海域表层沉积物中重金属铜铅锌镉的含量分布

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。     

DIRECT AND SIMULTANEOUS DETERMINATION OF Zn, Cd, Pb, Cu and Bi IN SEAWATER BY DERIVATIVE-VOLTAMMETRY

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.     

Distribution and partitioning of trace metals (Cd,Cu, Ni,Pb, Zn) in Galveston Bay waters

The distribution of several trace metals has been studied in the surface waters of Galveston Bay, Texas, in order to assess the impact of complexation with organic and reduced sulfur species on the partitioning of trace metals between particulate and aqueous species. The distribution of trace metals in the filter-passing fraction (<0.45 μm) showed two apparent trends: (1) the carrier phase metals (i.e., Fe and Mn) were largely removed in the Anahuac Channel region, which was dominated by direct Trinity River inputs; (2) the other metals (Cd, Cu, Ni, Pb, and Zn) showed non-conservative mixing behaviour, with mid-salinity maxima, within the estuarine regions of Galveston Bay. The average percentage of metal in the filter-passing fraction, as compared to the total metal load, decreased in that region from 95% to 9% in the order Ni>Cu>Cd>Zn>Pb>Mn>Fe, while an increasing trend was found in the same sequence for the acid-leachable fractions. The average values of K_d1, the particle-water partition coefficient, expressed as the ratio of weak acid-leachable particulate fractions to the filter-passing fractions, increased in the order Ni<Cu<Cd<Zn<Mn<Pb<Fe. This sequence is consistent with the relative importance of particulate transport of these trace metals from estuaries to coastal oceans. The observed decrease of K_d1 of Cu with increasing concentrations of suspended particulate matter (SPM), also called the “particle concentration effect” (PCE), can be eliminated when the free ionic, rather than the total concentration of Cu in the filter-passing fraction is used for calculating this ratio. A particle concentration effect would be expected if the binding of these trace metals by particles is mediated by solution (i.e., filter-passing) phase ligands. Complexation of Cd, Cu, Ni, Pb, and Zn with reduced sulfur species could be one of the causes for the observed linear correlations between metals and reduced sulfur species in both the filter-passing and filter-retained fractions. Significant correlations between Cu in the weak acid-leachable fraction and chlorophyll a (Chl a) concentrations suggest biological mediation of Cu uptake into the particulate fraction.     

图们江口水中Zn,Cd,Pb,Cu的形式分析

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。     

Accumulation of Zn,Cu and Cd by crabs and barnacles

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.     

FORM DISTRIBUTION OF Zn, Cd, Pb AND Cu IN WATERS OF THE NORTHWEST BOHAI GULF

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.     

东海—图们江水中Zn,Cd,Pb,Cu的形式分析

用防吸附物理涂汞电极反向极谱进行了东海至图们江水中Ｚｎ，Ｃｄ，Ｐｂ，Ｃｕ（１９９１年５－６月）的形式分析研究。结果表明，该４种元素不稳定态的平均浓度分别为５．７，０．０６０，０．０３５，０．６２μｇ／Ｌ，分布较为均匀。该结果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，Ｐｂ，Ｃｕ和颗粒态的Ｚｎ，Ｃｕ的较高含量，位于长江口及东海水中。     

RESEARCH ON THE DETERMINATION OF Pb, Cd, Cu AND Zn IN SEAWATER BY STRIPPING VOLTAMMETRY

In this paper, a comparison viral made between the two results of determining Pb, Cd, Cu and Zn in seawater by direct current (tripping voltammetry (DCS) with rotating glass carbon electrode and by differential pulse stripping voltammetry (DPS) with hanging mercury drop electrode (HMDE). By DCS, the range of linear calibration curves obtained was 4×10-3 M-2×10-7M for Cu, Zn and Cd, and 4× 10-9M-2×10-3M for Pb. By using DPS, the range of linear calibration curve was as follows: Cu 0.65-1.9 ppb; Pb 1.0-10 ppb; Zn 0.65-2.0 ppb; Cd 0.02-0.14 ppb. It was found that DCS could be used for determining Pb, Cu, Zn in coastal waters, but it is necessary to add gallium ion to it to eliminate the interference of Cu-Zn inter-metallic compound for determining Zn. The DPS is better for determinig Cd.     

离子交换—原子吸收光谱法测定海水中痕量铜、铅、锌、镉、铁、锰

本文介绍了用国产D401型螯合树脂分离富集海水中铜、铅、锌、镉、铁、锰等痕量元素,并用原子吸收光谱仪测定其含量的方法。讨论了各元素的分离条件选择及干扰元素的影响,并与溶剂萃取法的结果作了比较。各元素检测的定量下限为:铜0.5μg/L、铅0.1μg/L、锌1.0μg/L、镉0.01μg/L、铁2.0μg/L、锰2.0μg/L。方法精密度在4—8％之间,回收率为90—102％。     

阳极溶出伏安法测定生物体中镉,铅和铜

本文研究了生物样的较佳消化方法、测定方法和影响条件。采用差示脉冲阳极溶出伏安法测定生物体中Cd、Pb 和Cu。结果表明,所采用的HNO_3-HClO_4常压湿法消化法简便、可靠且重现性好。方法的精密度(以相对标准偏差表示,Cd 为8.6%,Pb为5.8%,Cu 为6.4%)和准确度(以回收率表示,Cd 为89.7%,Pb 为97.5%,Cu 为102.3%)显示出对生物体中Cd、Pb、Cu 连续测定的可靠性。