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1.
于2008年3月至2009年1月用电感耦合等离子体质谱法(ICP-MS)对湛江港海水中的铜(Cu)、锌(Zn)、铅(Pb)、镉(Cd)进行调查。分析结果表明:2008年湛江港湾海水中Cu、Zn、Pb、Cd含量较低,年平均含量分别为4.46×10-3mg/L、14.2×10-3mg/L、0.795×10-3mg/L、0.588×10-3mg/L,总体上表层海水中Cu、Zn、Pb、Cd的含量均略低于底层海水。各季度海水中重金属含量的比较结果为:Cu的含量秋季>春季>夏季>冬季,Zn的含量夏季>春季>秋季>冬季,Pb的含量秋季>夏季>春季>冬季,Cd的含量冬季>夏季>秋季>春季。湛江港湾的Cu、Zn、Pb、Cd的含量均在中部水域湛江港码头核心作业区最高,港湾外较低;Zn、Cd在港湾内的含量较高。按照单因子污染指数法评价,湛江港湾海水中的Cu、Zn、Pb、Cd含量均低于国家二类海水水质标准规定的限值,水质较好。  相似文献   

2.
At present, the methods widely applied to assess ecological risk of heavy metals are essentially single-point estimates in which exposure and toxicity data cannot be fully used and probabilities of adverse biological eff ects cannot be achieved. In this study, based on investigation of concentrations of six heavy metals (As, Hg, Pb, Cd, Cu, and Zn) in the surface seawater and sediment near the outlet of a zinc factory, located in Huludao City, Liaoning Province, China, a tiered approach consisting of several probabilistic options was used to refine ecological risk assessment for the individuals. A mixture of various heavy metals was detected in the surface seawater, and potential ecological risk index (PERI) was adopted to assess the potential ecological risk of heavy metals in the surface sediment. The results from all levels of aquatic ecological risk assessment in the tiered framework, ranging from comparison of single eff ects and exposure values to the use of distribution-based Hazard Quotient obtained through Monte Carlo simulation, are consistent with each other. Briefly, aquatic Zn and Cu posed a clear ecological risk, while Cd, Pb, Hg, and As in the water column posed potential risk. As expected, combined ecological risk of heavy metal mixture in the surface seawater was proved significantly higher than the risk caused by any individual heavy metal, calculated using the concept of total equivalent concentration. According to PERI, the severity of pollution by the six heavy metals in the surface sediment decreased in the following sequence: Cd>Hg>As>Pb>Cu>Zn, and the total heavy metals in the sediment posed a very high risk to the marine environment. This study provides a useful mathematical framework for ecological risk assessment of heavy metals.  相似文献   

3.
Twenty-nine samples of surface sediments from tidal flats in the Northern Shandong Province were collected for grain size, heavy metal(Hg, Cu, Pb, Zn, Cd, and Cr), and oil pollution analyses. The geoaccumulation index(Igeo) and factor analysis were introduced to evaluate sediment quality and source of contaminants. The mean concentrations of Hg, Cu, Pb, Zn, Cd, Cr, and oil in the surface sediments in the study area are 0.033, 17.756, 19.121, 55.700, 0.291, 59.563, and 14.213 μg g-1, respectively. The heavy metal contamination in the old delta lobe is slightly higher than that in the abandoned delta lobe; however, the opposite was observed for oil pollution. The Igeo results revealed that the overall quality of the surface sediments in the study area is in good condition. The heavy metal pollution levels show a descending order: Cd Hg Cr Cu Zn Pb, Cd being the main pollutant. The contamination level for in the study area is relatively lower than those for China's other tidal flats. Heavy metals are mainly derived from natural sources of rock weathering and erosion, partly influenced by industrial and agricultural discharge. However, oil pollution is mainly from runoff input, motorized fishing boat sewage, and oil exploitation.  相似文献   

4.
Historical records of metal inputs were studied by using a sediment core collected from a sand-rich mudflat in the Qinjiang River estuary, China. 210Pb chronology was used to reconstruct the fluxes of Hg, Cu, Pb, Zn, Cd, Cr and As to the core site during the last 86 years. Based on the constant initial concentration model, the sedimentation rates are 1.18 cm year-1 in the top 30 cm sandy layer and 0.92 cm year-1 in the muddy bottom layer. To compensate for grain-size and mineralogy effects on metal concentra-tions, aluminum was used as the normalizing element. The enrichment factors (EF) indicate that the natural inputs had prevailed up to the early 1980s. After this period, the intensity of human activities has resulted in continual increasing trend of metals towards the surface. Recent sediment samples from the Qinjiang River estuary are found moderately enriched by Cd (EF>1.5) and slightly enriched by other metals (EF<1.5). Considering that the drainage area of the Qinjiang River is mostly agricultural land, the increased Cd may be due to the usage of fertilizers and pesticides in agricultural activities and the combustion of fossil fuels.  相似文献   

5.
The southern sea area of the Huludao City, Liaoning Province might be polluted by heavy metals because it is close to the Jinzhou Bay, one of the heaviest sea area polluted by heavy metals in China. The undisturbed modern sediment core can be used to analyze the accumulation and source of the pollutants using 137 Cs and 210 Pb ex . Thirty-five samples of surface sediment and two core sediments were collected from the southern sea area of Huludao City. The concentrations of copper (Cu), lead (Pb), chrome (Cr), zinc (Zn), arsenic (As) and mercury (Hg) in the surface sediments as well as Cu, Pb, Zn, Cr, 137 Cs and 210 Pb ex in the core sediments were determined to research the spatial distribution and accumulation characteristics, and to analyze the sources and the potential risks of heavy metals. The results show that the pollution levels of Zn and Hg are serious, and 26 stations are at moderate or heavy ecological risks. The concentrations of the heavy metals increase from east to west, as well as from open sea to offshore marine area. The concentrations of heavy metals are not high in the sediments adjacent to the Jinzhou Bay, and the influence caused by the seawater exchange with the Jinzhou Bay is little. The concentrations of the heavy metals in the core sediments show low-high-low characteristic, and it coincides with the pollution history of Huludao City. The atmospheric deposition of heavy metals from the Huludao Zinc Plant is likely to be the main source of pollution without direct discharge of wastewater. The high concentrations of heavy metals appear on the upper sediment of 20 cm. The shallow sediment with high heavy metal contents might be exposed to surface when it was disturbed by the ocean engineering and big storm surge, then cause risk to the safety of aquaculture and human healthy.  相似文献   

6.
Accumulation of metals in both sediments and Phragmites australis organs was studied. Samples were collected from seven stations located in Anzali wetland, Iran. The samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that concentration of the studied metals (except As and Cd) were higher in sediments than in P. australis organs. Metal accumulation was found to be significantly (P <0.05) higher in roots than in above-ground organs of P. australis. The bioaccumulation factor (BAF) and the transfer factor (TF) also verified the highest rate of metal accumulation in roots and their reduced mobility from roots to the above-ground organs. Pearson correlation coefficient showed significant relationships between metal concentrations in sediments and those in plant organs. It should be pointed out that sediment and plant samples exhibited higher metal concentrations in eastern and central parts than in western and southern parts of the wetland. The mean concentrations of all studied elements (except for Fe, V and Al) were higher in these sediment samples than in the Earth’s crust and shale. High accumulation of metals in P. australis organs (roots and shoots) is indicative of their high bioavailability in sediments of the wetland. The correlation between metal concentrations in sediments and in P. australis indicates that plant organs are good bioindicators of metal pollution in sediments of Anzali wetland.  相似文献   

7.
Metal pollution has become an major issue governing the wetland ecosystem health.The southern coastal wetland of the Qiangtang Estuary are facing unusual perturbation due to rapid development along the embayment in recent decades.This study evaluated the bioavailability of metals(Cu,Pb,Cd,Cr and Zn)in the sediment of the southern coastal wetland of the Qiangtang Es-tuary using diffusive gradients in thin films(DGT)techniques and compared with several methods based on total metal content.The results showed that the contents of Cr,Pb,Cd and Cu in sediment,as detected using DGT,were considerably correlated with the exchangeable fraction and the content in Phragmites australis roots,while a weak correlation was observed for Zn.Therefore,DGT analysis could be used to evaluate the bioavailability and potential risk of Cr,Cd,Pb and Cu for P.australis.Quantitative indices,such as DGT concentration,bioaccumulation in P.australis,geoaccumulation index(Igeo)and potential ecological risk index(RI),revealed that Cd was a major potential ecological risk factor along the southern coast wetland of the Qiantang Estuary,especially in the upstream region,which is potentially more vulnerable to the anthropogenic pollution.  相似文献   

8.
We analyzed heavy metal concentrations in a number of surface sediments and cores from the Qiongzhou Strait and surrounding marine areas.The areas of high concentrations are primarily outside the eastern mouth of the Qiongzhou Strait and on the west side of the Leizhou Peninsula,whereas the areas of low concentrations are located primarily in the eastern Qiongzhou Strait.The maximum Cd,Pb and Zn concentrations in the samples collected in our study do not exceed the official standards for marine sediments,whereas the concentrations of Cr and Cu slightly exceed the standards.Correlations exist between the concentrations of Cu,Pb,Zn,Cr and Cd,and the concentrations of these metals are positively correlated with the mean particle size(φ value),indicating that the finer sediments have adsorbed greater amounts of heavy metal elements than the coarser sediments.An evaluation of the potential environmental risks demonstrates that certain indices of heavy metal pollution and environmental risks are relatively low and may be assigned low risk levels,thereby indicating that,in terms of heavy metals,the marine sedimentary environment in this region is only mildly impacted.Our analysis of the contaminant origins shows that the heavy metals in this region primarily originate in the Pearl River Estuary and that a small amount of them is derived from local runoff.The elevated heavy metal concentrations from the upper sections of the cores started 130 years ago,which indicats that heavy metals in the surface sediments are primarily due to human activities associated with industrialization.  相似文献   

9.
The concentrations of Zn, Cd, Pb, Cu ions are shown to be similar in natural waters of Tianshan Mountains and Qinghai-Tibet plateau and to be similar in those of the sea water. The average and variability of concentraions of trace metal ions in fresh water are Zn 5.7±1.5, Cd 0.092±0.038, Pb 0.048±0.011, and Cu 1.1±0.20 ppb. The average concentrations in the East China Sea are Zn 7.3 (5.5 in 1976), Cd 0.12, Pb 0.036, and Cu 0.94 ppb. It proves that the homogeneous distribution of trace metal ions (free ion and unstable complexes) in natural waters is present in the nature as a rule. Contribution No. 985 from the Institute of Oceanology, Academia Sinica.  相似文献   

10.
The waters with salinity from 10 to 23 comprise the main removal region of ion and particulateforms of heavy metals in the Changjiang estuary.The positive correlationships between Zn,Cd,Pb,Cuand the reciprocal of transparency,COD and chlorophyll-a showed that the removal of heavy metalsclosely correlate with the distribution of suspensions,the adsorption of organic materials and theassimilation by organisms.The removal of heavy metals in the Changjiang estuary water were consistentwith the sedimentation rate of the sediments in these waters,sediment types and the distributions ofheavy metals contents in the sediments.  相似文献   

11.
Discharge of heavy metals from metal processing industries is known to have adverse effects on the environment. Biosorption of heavy metals by metabolically inactive biomass of microbial organisms is an innovative and alternative technology for removal of these pollutants from aqueous solution. The search of marine actinobacteria with potential heavy metal biosorption ability resulted in the identification of a novel alkalophilic Streptomyces VITSVK5 species. The biosorption property of Streptomyces VITSVK5 spp. was investigated by absorbing heavy metals Cadmium (Cd) and Lead (Pb). Physiochemical characteristics and trace metal concentration analysis of the backwater showed the concentrations of different metals were lead 13±2.1 μg L−1, cadmium 3.1±0.3μg L−1, zinc 8.4±2.6μg L−1 and copper 0.3±0.1μg L−1, whereas mercury was well below the detection limit. The effect of pH and biomass dosage on removal efficiency of heavy metal ions was also investigated. The optimum pH for maximal biosorption was 4.0 for Cd (II) and 5.0 for Pb (II) with 41% and 84% biosorption respectively. The biosorbent dosage was optimized as 3 g L-1 for both the trace metals. Fourier transform infrared absorption spectrum results indicated the chemical interactions of hydrogen atoms in carboxyl (-COOH), hydroxyl (-CHOH) and amine (-NH2) groups of biomass with the metal ions. This could be mainly involved in the biosorption of Cd (II) and Pb (II) onto Streptomyces VITSVK5 spp. The results of our study revealed Streptomyces metabolites could be used to develop a biosorbent for adsorbing metal ions from aqueous environments.  相似文献   

12.
Nine chemical species of Zn, Cd, Pb and Cu in the Zhujiang River estuary were measured by using the technique of ion-exchange, ultraviolet irradiation and anodic stripping voltammetry. According to the distribution of the nine species in percentage an estuarine chemical pattern of the metal elements Zn, Cd, Pb and Cu in the Zhujiang River estuary was roughly made, and its is suggested that this estuary has relatively great self purifying ability in respect to heavy metal pollution. This paper was published in Chinese in theOceanologia et limnologia sinica 13(1): 19–25, 1983.  相似文献   

13.
Heavy metal pollutants are a worldwide concern due to slow decomposition, biocondensation, and negative effects on human health. We investigated seasonal and spatial variations of the five heavy metals and evaluated their health risk in the Liaohe River, Northeast China. A total of 324 surface water samples collected from 2009 to 2010 were analyzed. Levels (high to low) of heavy metals in the Liaohe River were: zinc (Zn) > chromium (Cr) > copper (Cu) > cadmium (Cd) > mercury (Hg). Spatial and seasonal changes impacting concentrations of Cu and Zn were significant, but not significant for Cr, Cd and Hg. The highest concentrations of heavy metals were: Hg at Liuheqiao, Cu at Fudedian, Zn at Tongjiangkou, Cr at Mahushan, and Cd at Shenglitang. The highest concentrations of Hg and Cr were found in the wet period, Cu and Cd in the level period, and Zn in the dry period. The surface water of a tributary was an important accumulation site for heavy metals. Health risks from carcinogens and non-carcinogens increased from upstream to downstream in the mainstream of the Liaohe River. The total health risk for one person in the Liaohe River exceeded acceptable levels. The total health risk was the greatest during the wet period and least in the dry period. Among the five heavy metals in the Liaohe River, Cr posed the greatest single health risk.  相似文献   

14.
于2005年8月对湛江港附近海域潮间带的海水、表层沉积物和贝类体内的重金属进行了分析,结果表明:海水中的砷优于海水水质Ⅰ类标准,而汞、铜、锌、铅、镉均有不同程度的污染,其中铜、铅、镉污染较为严重,均劣于海水水质Ⅳ类标准;表层沉积物中砷的含量低于全国海岸带背景值,而汞、铜、锌、铅、镉均高于全国海岸带背景值,其标准指数分别为1.35、1.66、1.50、2.08、3.10,汞、铜略高于海洋沉积物质量标准第一类标准,有轻微污染,砷、锌、铅均低于海洋沉积物质量标准第一类标准,未受污染,而镉略高于海洋沉积物质量标准第二类标准,环境受镉污染。各元素在各站点的分布没有规律性。牡蛎和蛤仔体内各重金属含量均优于海洋生物污染评价标准和人体消费卫生标准,其卫生质量良好。  相似文献   

15.
1IN T R O D U C T IO N With therapiddevelopment of urbanizatio,nurban land was exploitedand utilizetdoform differendtomains be- ing subjectto many potentialpollutionsourcessuch as vehicleemission, industrialactivitieasnd household garbage.Particularl, yur…  相似文献   

16.
A study was conducted on Cu, Zn, Cd, Fe, Co and Ni levels in Saanich Inlet anoxic seawater. Data on the concentration of these trace metals and H2S, and other oceanographic parameters were obtained in four cruises. Equilibrium models are presented together with in situ data. The results strongly support the assumption that the solubilities of Cu, Zn, Cd, Fe, Co and Ni are controlled by bisulfide and/or polysulfide complexes. The species of Cu, Zn, Cd and Ni are shown to be Cu(S4) 2 3− and Cu(Sn4S5)3−, Zn(HS) 2 0 and ZnHS 2 , Cd(HS) 2 0 and Ni(HS) 2 0 , respectively. The solid species controlling Fe2+ and Co2+ are respectively the pyrohotites FeS and CoS. The data illustrates that thermodynamic equilibrium has been established in the H2S-controlled seawater of Saanich Inlet, and that equilibrium has not been established in the H2S−O2-coexisted seawater of Saanich Inlet. The lack of equilibrium in the H2S−O2-coexisted seawater is a result of the flushing or mixing of oxygenated seawater with anoxic water. The new species of trace metals are still in the processes of reduction and precipitation. Contribution No. 1428 from Institute of Oceanology, Academia Sinica  相似文献   

17.
The tidal flat along the Changjiang(Yangtze) River estuary has long been reclaimed for the agricultural purposes, with the prevailing hydrological conditions during such pedogenic transformations being of great importance to their successful development. In this study, samples of surface sediment from Chongming Dongtan, situated at the mouth of the Changjiang River estuary, were collected and analyzed in order to understand how hydrological management can influence the concentrations of heavy metals and salt ions in pore water, and chemical fractionation of heavy metals during the reclamation process. We performed a series of experiments that simulated three dif ferent hydrological regimes: permanent flooding(R1), alternative five-day periods of wetting and drying(R2), continuous field capacity(R3). Our results exhibited good Pearson correlations coefficients between heavy metals and salt ions in the pore water for both R1 and R2. In particular, the concentrations of salt ions in the pore water decreased in all three regimes, but showed the biggest decline in R2. With this R2 experiment, the periodic concentration patterns in the pore water varied for Fe and Mn, but not for Cr, Cu, Pb and Zn. Neither the fractionation of Ni nor the residual fractions of any metals changed significantly in any regime. In R1, the reducible fractions of heavy metals(Cr, Cu, Zn and Pb) in the sediment decreased, while the acid extractable fractions increased. In R2, the acid extractable and the reducible fractions of Cr, Cu, Zn and Pb both decreased, as did the oxidizable fraction of Cu. These data suggest that an alternating hydrological regime can reduce both salinity and the availability of heavy metals in sediments.  相似文献   

18.
Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values,concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4^-, NO3^-, PO43^-, SiO32^-) were performed.Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2-3 times higher than that in the southern Yellow Sea. In individual, Pb and PO4^3- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions.  相似文献   

19.
The sea fluxes of trace metals, POC, and settled material were studied in anoxic seawater, Saanich Inlet, B. C., Canada with sediment traps. This paper discusses the change of mass fluxes of sediment, trace metals and POC for various seasons and depths. The annual mean of settled material is 1.56 g.m−2.a−1, 84.6 mg. m−2.a−1 for POC, 60.0 mg. m−2.a−1 for Cu, 16.5 mg.m−2.a−1 for Pb, 189 mg.m−2.a−1 for Zn, 2.20 mg.m−2.a−1 for Cd, 699 mg.m−2.a−1 for Fe, 38.8 mg.m−2.a−1 for Co, and 84.6 mg.m−2.a−1 for Ni. The relations between the average fluxes of trace metals and POC, the fluxes of trace metals and settled matter, and the sea fluxes of trace metals and Fe are in linear progression. The resident times of elements as calculated from sea flux, are 1.1 a. for Cu, 0.014 a. for Pb, 0.50 a. for Zn, 3.8 a. for Cd, 0.16 a. for Fe, 0.39 a. for Co, and 1.14 a. for Ni. The order of resident times is as follows: Pb−Fe−Co−Zn−Cu−Ni−Cd. The metal resident times in Saanich Inlet are shorter than the values estimated for the open ocean. It illustrates that the biochemical processes in shallow Saanich Inlet are faster than those in the open ocean, and that debries of plankton and fecal pellets of zooplankton play an important role in vertical transport of organic carbons. Contribution No. 1650 from the Institute of Oceanology, Academia Sinica.  相似文献   

20.
Core sediments from the Muthupettai mangroves on the southeast coast of India were analyzed for soil texture,total nitrogen,organic carbon,phosphorus and heavy metals(Fe,Mn,Cr,Cu,Ni,Pb,Zn and Cd).The distinct seasonal variation in the distribution of metals in the sediments was observed.The minimum concentration was recorded in river mouth and the maximum was in lagoon.High metal concentration in sediment was observed during monsoon and low concentration in summer.The total nu-trient in lagoon and river mouth was recorded in the range of 4.528 to 8.526 mg g-1 for organic carbon,2.213 to 10.5 mg g-1 for nitro-gen and 0.824 to 7.22 mg g-1.  相似文献   

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