首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 718 毫秒
1.
Concentrations of Cd, Cr, Cu, Pb, and Zn were determined in algae samples collected from the Rabta Bay in the Mediterranean Sea, Algeria. The levels of heavy metals in the macroalgae, Ulva lactuca, Codium fragile (green algae), Jania rubens (red algae), and Dictyota dichotoma (brown algae) recorded high concentrations except for Cd. Moreover, Zn was the most predominant metal in the seaweeds. The obtained HM contents indicate that different species demonstrate various degree of metal accumulation and the obtained higher values in site 1 of the studied zone can be attributed to the discharge influence of two rivers (Mouttas and Larayeche Rivers), entering the Mediterranean Sea and local pollutant emissions. The abundance of heavy metal concentrations in the macroalgae samples was found in the order below: Zn > Cu > Pb > Cr > Cd from the studied zone. The highest amounts of heavy metals in algae samples were Cd, Cu, and Pb in brown algae, and Cr and Zn in green and brown algae from the studied zone (Rabta Bay).  相似文献   

2.
The Bay of Gokova in Southeastern Aegean Sea (Turkey) is important by the potential of agricultural, municipal, and tourism activities. In addition, there is no industrial plant within the area in the Aegean Sea. Kad?n Creek (Azmak) and Ak?ap?nar Creek (Azmak) flowing into the inner Gokova Bay are one of the important factors in determining the character of the inner Gokova Bay. In this study, nine stations were selected in the inner Gokova Bay, Kad?n Creek, and Akcap?nar Creek. The concentrations of Cd, Cu, Fe, Pb, and Zn were measured in suspended particulate matter (SPM) and sediments. The samples of sediments and SPM were collected in between February 2008 and September 2008. The aim of the study is searching the change of concentrations of Cd, Cu, Fe, Pb, and Zn in suspended particulate matter and sediments in the inner Gokova bay, Kad?n Creek, and Ak?ap?nar Creek. It has been identified that the metal concentrations in the creeks are higher than the metal concentrations in the marine environment. It has also been observed that the concentrations of Pb, Cd, and Cu in summer season have been higher than in the winter season, but the concentrations of Fe and Zn have not shown a significant difference between in summer and winter seasons. The obtained results show that the some heavy metals are caused by the agricultural, municipal, and tourism activities operating in the coastal areas and terrestrial environment, and they are transported from the creeks to the Gokova Bay by suspended particulate matter.  相似文献   

3.
The extent of pollution with organotin compounds and Cd, Pb, Ni, Cu, Zn, Cr, Mn, V, Co and Al was investigated in sediments and mussels (Mytilus galloprovincialis) from the Slovenian costal area of the Northern Adriatic Sea. Sampling was performed in Marina Portorož, Dockyard Izola, non exposed area of the Bay of Mesečev zaliv and in Mariculture Sečovlje. Mussels were taken in the summer and winter time, while sediments were collected during the winter sampling. Organotin compounds were determined by gas chromatography—mass spectrometry and metals by flame or electrothermal atomic absorption spectrometry. The accuracies of the analytical procedures were checked by the analysis of standard reference materials CRM 477 mussel tissue and PACS 2 marine sediment (organotin compounds) and SRM 2976 mussel tissue and CRM 320 river sediment (metals). Good agreements between certified and determined values were obtained. Normalization procedure to Al was applied to estimate the anthropogenic inputs of metals in sediments. The analyses of sediments demonstrated moderate pollution with organotin compounds in Marina Portorož and in Dockyard Izola. Concentrations of tributyltin species were higher than those of dibutyltin and monobutyltin. In mussels substantial contamination with tributyltin was observed in Marina Porotrož and Dockyard Izola. The extent of pollution was higher in the winter time. The analysis of metals in sediments exhibited elevated concentrations in Marina Portorož and Dockyard Izola. Data from the normalization procedure indicated the anthropogenic inputs of Cu, Zn and Cr in Marina Portorož and Mn in Bay of Mesečev zaliv and Dockyard Izola. Mussels, as accumulators of pollutants, in general contained higher metal concentrations during winter time in Dockyard Izola.  相似文献   

4.
The contents of heavy metals (Fe, Mn, Pb, Cu, Cd, and Hg) dissolved in water and suspended solids of Gökova Bay—partly and fully sampled in 2005 and 2006, respectively—are quite higher than the average values encountered in uncontaminated sea water. The high concentrations are associated with terrestrial inputs from the mining zones and anthropogenic (domestic + industrial) sources. Moreover, the distribution of Fe and Cu is affected by primary production because these elements function as nutrients in biological activities. The Cr, Ni, and Fe concentrations of surface sediments are above the shale average. The Cr and Ni contents of surface sediments representative of river mouths strongly correlate with total phosphorus contents. In a sulfide-poor environment, Pb and Cu were concentrated at a higher ratio in surface sediments than Cd, probably due to higher stabilities of their surface complexes with amorphous iron oxides and clay minerals existing as major components in the sediments. The exceptional enrichment of Zn may be attributed to double oxide formation with amorphous iron oxides in sediments. The high metal values are most probably caused by terrestrial inputs from anthropogenic sources and the mining zones at the southeast part of the bay. The Al, Mn, Pb, Cu, Zn, and Hg contents are below the shale average. The low values have possibly originated from the coarse-grained sandy sediments having a low affinity for metals. There are no distinct differences in the metal distributions in water and suspended matter between the years 2005 and 2006 in the bay, probably due to low sedimentation rates.  相似文献   

5.
Suspended particulate matter (SPM), sediments and clams were collected at three sites in Jiaozhou Bay to assess the magnitude of trace metal pollution in the area. Metal concentrations in SPM (Cu: 40.11-203; Zn: 118-447; Pb: 50.1-132; Cd: 0.55-4.39; Cr: 147.6-288; Mn: 762-1670 microg/g), sediments (Cu: 17.64-34.26; Zn: 80.79-110; Pb: 24.57-49.59; Cd: 0.099-0.324; Cr: 41.6-88.1; Mn: 343-520 microg/g) and bivalves (Cu: 6.41-19.76; Zn: 35.5-85.5; Pb: 0.31-1.01; Cd: 0.51-0.67; Mn: 27.45-67.6 microg/g) are comparable to those reported for other moderately polluted world environments. SPM showed a less clear pattern. Metal concentrations in sediments displayed a clear geographical trend with values increasing with proximity to major urban centers. The clams (on dry weight) showed a complex pattern due to the variability introduced by age-related factors. Cd showed an apparent reverse industrial trend with higher concentrations in clams collected at distant stations. Zn, Pb and Mn showed no clear geographical pattern, whereas Cu increased in the clams collected in the most industrialized area. In addition, the bioaccumulation factors (BAF) were calculated. The result indicated that the studied Ruditapes philippinarum in Jiaozhou Bay possessed different bioaccumulation capacities for Cd, Zn, Cu, Pb and Mn, and Cd, Zn had a relatively high assimilation of those metals from sediment particles. A significant relationship with clam age was observed for Zn (positive) and Cu (negative) suggesting different physiological requirements for both metals with age. Trace metal concentrations measured in the tissue of the investigated clam were in the range considered safe by the WHO for human use.  相似文献   

6.
A combined approach consisting of monitoring and thermodynamic modeling was used in order to calculate the concentration of trace element species in water samples of a broad salinity range and to explain their chemical behaviour. The study was performed on water samples (fresh, marine, hyper-saline) taken from the area of Burgas Bay, Bulgaria. The ion association model based on Debye-Hückel theory using the sst2008.dat database and the ion interaction model based on Pitzer theory using a new pit2010.dat database were compared and combined for the purposes of this study. The new pit2010.dat database combines the sst2008.dat database and the pitzer.dat database of the PHREEQCI computer program as well as the thermodynamic data for the elements Fe, Mn, Cu, Zn, Cd and Pb and their Pitzer ion interaction parameters. The results showed that: (1) the predominant species in fresh waters were free ions of Mn(2+) (73.6%), Zn(2+) (58.0%) and Cd(2+) ions (78.3%) as well as carbonate species CuCO?? (81.8%), PbCO?? (77.2%) and hydroxy species Fe(OH) ??(55.2%) and Fe(OH)+?(35.6%); (2) an increase in chloride species MeCl2(n)-(n)(n = 1-4, Me = Mn, Zn, Cu, Pb and Cd) and of the hydroxy species Fe(OH)?? for Fe was calculated for sea and hyper-saline water.  相似文献   

7.
As part of an assessment of land-based sources of pollution in Jobos Bay, Puerto Rico, sediment samples were collected at 43 sites to characterize concentrations of a suite of pollutants, including metals. Fifteen major and trace metals (Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn Ni, Pb, Sb, Se, Sn, and Zn) were measured along with total organic carbon and grain size in surficial sediments. For most metals, maximum concentrations were seen in the eastern bay; however, values were still within concentration ranges found in other estuarine systems. In contrast, silver was higher in the western region. In general, metal distribution in the bay was positively correlated with grain size. Additionally, correlations between Al and other metals suggest natural sources for metals. The data presented here suggest that, although the Jobos Bay watershed contains both urban centers along with industrial and agricultural developments, anthropogenic inputs of metals may be negligible.  相似文献   

8.
Fractionation and elemental association of Zn, Cd, and Pb in soils near Zn mining areas were studied using a continuous-flow sequential extraction approach. The recently developed sequential extraction procedure not only gave fractional distribution data for evaluation of the mobility or potential environmental impact of the metals, but also the extraction profiles (extractograms) which were used for study of elemental association. In addition, the elemental atomic ratio plot extractogram can be used to demonstrate the degree of anthropogenic contamination. Seventy-nine soil samples were collected in the vicinity of a Zn mine and were fractionated into 4 phases i.e. exchangeable (F1), acid soluble (F2), reducible (F3) and oxidizable (F4) phases. Most samples were contaminated with Zn, Cd and Pb. The reducible phase is the most abundant fraction for Zn and Pb (>50%) while Cd is concentrated in the first 3 extraction steps. The distribution patterns of Cd were obviously affected by soil pH. 55% of Cd appears predominantly in the F1 fraction for acidic soils while in neutral and alkaline soils, it was mostly (70%) found in the F2 + F3 fractions. The extractograms obtained from the continuous-flow extraction system revealed close association between Zn, Cd, Pb and Fe in the acid soluble phase, Cd-Pb and Zn-Fe in the reducible phase for contaminated soils. A correlation study of the 3 metals using a correlation coefficient was also performed to compare the results with the elemental association revealed by the extractograms. Atomic ratio plot extractograms of Zn/Fe, Cd/Fe and Pb/Fe in the reducible phase, where contaminated metals are predominant, can be used to evaluate the degree of anthropogenic contamination. From the elemental atomic ratio plot, it is obvious that the contaminants Cd and Pb are mostly adsorbed on the surface of Fe oxides. Zn, which is present in an approximately 1 ratio 1 ratio with Fe in contaminated soils, does not show a similar trend to that found for Cd and Pb.  相似文献   

9.
Surface sediments collected from nine stations in Nemrut Bay, Aegean Sea were analyzed for trace metals (Hg, Cd, Pb, Cr, Cu, Zn, Mn, Ni, Fe, As, and Mg) and grain sizes. The results were compared with the numerical sediment guidelines used in North America as well as literature values reported for similar studies conducted in Izmit Bay and Izmir Bay. The metal levels were also evaluated according to the enrichment factor and contamination factor analyses. The analyses revealed significant anthropogenic pollution of Hg, Pb, Zn, and As in the surficial sediments of Nemrut Bay.  相似文献   

10.
The distribution and accumulation of trace metals in the sediments of the Cochin estuary during the pre-monsoon, monsoon and post-monsoon periods were investigated. Sediment samples from 14 locations were collected and analysed for the metal contents (Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb), organic carbon, total nitrogen, total sulphur and grain size. The data were processed using statistical tools like correlation, factor and cluster analysis. The study revealed an enrichment of Cd and Zn in the study area particularly at station 2, which is confirmed by enrichment factor, contamination factor and geoaccumulation index. The factor analysis revealed that the source of Cd and Zn may be same. The study indicated that the spatial variation for the metals like Mg, Cr, Fe, Co, Ni, Cu, Zn, Cd and Pb were predominant unlike Mn which shows a temporal variation. The strong association of trace metals with Fe and Mn hydroxides and oxides are prominent along the Cochin estuary. The anthropogenic inputs of industrial effluents mainly control the trace metals enrichment in the Cochin estuary.  相似文献   

11.
The concentrations of Cr, Ni, Cu, Zn, Cd, and Pb in superficial sediment samples collected from three representative sites (Yuqiao Reservoir, Haihe River, and Haihe River Estuary) in Tianjin, North China, were analyzed using various single extraction and sequential extraction procedures to determine their remobilization, extractability, and distribution patterns. Sediments from the Haihe River had higher metal concentrations and geo-accumulation indices, especially for Cd and Zn, than sediments from the other two sites, suggesting that the Haihe River has been heavily influenced by anthropogenic activities. In addition, over 31% and 28.2% of the total Cd in the Haihe River and the Yuqiao Reservoir, respectively, and 18.2% of the total Zn in the Haihe River were found to be associated with the exchangeable form, indicating the significant remobilization of Cd and Zn when compared with Cr and Ni. However, over 98% of the Ni and 78% of the Cr were most closely associated with the residue and oxidizable fractions, which resulted in their becoming environmentally immobile. Based on the Environmental Protection Agency method 3050B, Cd and Zn had the greatest extraction efficiency when a single extraction procedure using 0.5-mol L???1 HCl, 0.43-mol L???1 HAcO, and 0.05-mol L???1 ethylene-diamine-tetra-acetic acid was conducted, with extraction yields of up to 72%, 68%, and 56% for Cd and 50%, 49%, and 29% for Zn, respectively, being obtained for the Haihe River sediments. This was followed by the yields of Cu and Pb and, finally, those of unpolluted metals such as Cr and Ni. HCl and acetic acid extraction provided equivalent information for predicting Cd and Zn mobility in the sediments studied and produced suitable results for quick screening.  相似文献   

12.
Concentrations of Cd, Cu, Co, Zn, Mn and Fe were determined in biota and sediment samples collected from the Eastern Harbour and El-Mex Bay in the Mediterranean Sea, Egypt. The levels of Cu, Co, Zn, Mn and Fe in the macroalgae, Ulva lactuca, Enteromorpha compressa (green algae) and Jania rubens (red algae), recorded high concentrations except for Cd. Moreover, Fe was the most predominant metal in the seaweed. The two species of bivalves, Donax trunculus and Paphia textile, showed different amounts of metals in their tissue. The abundance of heavy metal concentrations in the mussel samples was found in the order Fe> Zn> Mn> Cu> Co> Cd and Fe> Zn> Mn> Cu> Cd> Co, respectively for the two species. The metals concentrations were generally higher compared with the previous studies in mussels from the same area. The levels of metals accumulated in the investigated fish samples, Saurida undosquamis, Siganus rivulatus, Lithognathus mormyrus and Sphyraena sphyraena, were higher than those of Marmara Sea (Turkey), for Co and Cd and lower for Cu, Zn, Mn and Fe. El-Mex Bay having the highest metals concentration in sediments as their order of abundance were Fe> Zn> Mn> Cu> Cd> Co. Nevertheless, a high variability in the metal levels occurs among the studied algae and biota and also between the investigated Harbour. A significant correlations (p < 0.05) were found for each of Zn and Fe in P. textile and of Co in D. trunculus relative to their concentrations in surficial sediments.  相似文献   

13.
Thirty-nine samples of recent bottom sediments were collected from Mabahiss Bay, north of Hurghada City, Red Sea, Egypt. The collected samples were subjected to a total digestion technique and analyzed by absorption spectrometer for metals including Pb, Zn, Cd, Ni, Co, Cu, and Mn. Concentration data were processed using correlation analysis, principal component analysis, and hierarchical cluster analysis. Multivariate statistical analysis classified heavy metals in the study area into different groups. The pollution level attributed to these metals was evaluated using geoaccumulation index and contamination factor in order to determine anthropogenically derived sediment contamination. The results of both geoaccumulation index and contamination factor results reveal that the study area is not contaminated with respect to Zn, Ni, Cu, and Mn; uncontaminated to moderately contaminate with Pb; and moderately to strongly contaminate with Cd. The high contents of Pb, Cd, and Co in the study area result from various anthropogenic activities including dredging, land filling, localized oil pollution, using of antifouling and anticorrosive paints from fishing and tourist boats, and sewage discharging from various sources within the study area.  相似文献   

14.
Suspended particulate matter (SPM), sediments and clams were collected at three sites in Jiaozhou Bay to assess the magnitude of trace metal pollution in the area. Metal concentrations in SPM (Cu: 40.11–203; Zn: 118–447; Pb: 50.1–132; Cd: 0.55–4.39; Cr: 147.6–288; Mn: 762−1670 μg/g), sediments (Cu: 17.64–34.26; Zn: 80.79–110; Pb: 24.57–49.59; Cd: 0.099–0.324; Cr: 41.6–88.1; Mn: 343−520μg/g) and bivalves (Cu: 6.41–19.76; Zn: 35.5–85.5; Pb: 0.31–1.01; Cd: 0.51–0.67; Mn: 27.45−67.6 μg/g) are comparable to those reported for other moderately polluted world environments. SPM showed a less clear pattern. Metal concentrations in sediments displayed a clear geographical trend with values increasing with proximity to major urban centers. The clams (on dry weight) showed a complex pattern due to the variability introduced by age-related factors. Cd showed an apparent reverse industrial trend with higher concentrations in clams collected at distant stations. Zn, Pb and Mn showed no clear geographical pattern, whereas Cu increased in the clams collected in the most industrialized area. In addition, the bioaccumulation factors (BAF) were calculated. The result indicated that the studied Ruditapes philippinarum in Jiaozhou Bay possessed different bioaccumulation capacities for Cd, Zn, Cu, Pb and Mn, and Cd, Zn had a relatively high assimilation of those metals from sediment particles. A significant relationship with clam age was observed for Zn (positive) and Cu (negative) suggesting different physiological requirements for both metals with age. Trace metal concentrations measured in the tissue of the investigated clam were in the range considered safe by the WHO for human use.  相似文献   

15.
Foliar Cd and Zn concentrations of hybrid poplars commonlyplanted on sediment-derived soils were assessed in field circumstances. Selected sites covered a range of soil types andplantation characteristics. Reference data for foliar concentrations were established from samples taken in a tree-nursery. Even in the reference situation a large variationin foliar Cd and Zn concentrations was observed, with relative standard deviations in the order of 15%. Foliar concentrations of Cd and Zn in poplars growing on sediment-derived soils increased during the growing season. The accumulation rate was markedly higher on polluted sediment-derived soils than in thereference situation. Poplars grown on polluted sedimentderived soils showed elevated and deviating foliar Cd and Znconcentrations (>7.5 mg Cd kg-1 DW and 320 mg Zn kg-1 DW). A thin unpolluted covering layer did not influence foliarconcentrations. Regardless of site characteristics, poplarage, species or clone, a significant positive relation wasfound between soil and foliar concentration for Zn and to alesser extent for Cd. Bioconcentration factors for Cd and Znwere higher than one in baseline situations, but mostly lowerthan one on polluted sediment-derived soils. Cd:Zn ratio wason the average twice as high as in the soil. Leaf beetlesshowed normal body concentrations for Zn, but higher Cdconcentrations than in reference situations. BCFs were lowerthan one on sediment-derived soils. Foliar results indicateda possible threat in long-term habitat development of poplarplantations. This conclusion was confirmed by the significanthigher Cd concentrations in leaf beetles grown on poplarswith deviant foliar concentrations. However, litterdecomposition rates were generally evaluated as normal.  相似文献   

16.
A detailed investigation was conducted to evaluate heavy metal sources and their spatial distribution in agricultural fields in the south of Tehran using statistics, geostatistics, and a geographic information system. The content of Cd, Cu, Co, Pb, Zn, Cr, and Ni were determined in 106 samples. The results showed that the primary inputs of Cr, Co, and Ni were due to pedogenic factors, while the inputs of Zn, Pb, and Cu were due to anthropogenic sources. Cd was associated with distinct sources, such as agricultural and industrial pollution. Ordinary kriging was carried out to map the spatial patters of heavy metals, and disjunctive kriging was used to quantify the probability of heavy metal concentrations higher than their recommended threshold values. The results show that Cd, Cu, Ni, and Zn exhibit pollution risk in the study area. The sources of the high pollution levels evaluated were related to the use of urban and industrial wastewater and agricultural practices. These results are useful for the development of proper management strategies for remediation practices in the polluted area.  相似文献   

17.
The sea bream??s nematode and Sparus aurata, sampled from the Iskenderun Bay, Mediterranean, in March 2008 were analyzed by inductively coupled plasma?Catomic emission spectrometry for their some heavy metal (Cd, Cr, Cu, Fe, Hg, Mn, Mg, Pb, and Zn) levels. The metal concentrations of the parasites were compared to different organs (liver, muscle, gill, intestine, and skin) of the fish hosts. There were significant differences in Cd, Cr, Cu, Fe, Mn, Zn, Hg, Mg, and Pb concentrations in tissues of fish and its parasite. The parasite Cd, Cu, and Pb concentration was higher than the other tissues. Furthermore, significant differences were detected in the heavy metal accumulations between the parasitized and unparasitized fish tissues in Cd, Cu, Hg, and Pb concentrations. The Cd, Hg, and Pb concentrations were found in fish muscle at mean concentrations over the permissible limits proposed by the Food and Agriculture Organization.  相似文献   

18.
The suitability of Mazzaella laminarioides and Sarcothalia crispata as heavy metal biomonitors of Cd, Cu, Hg, Pb, and Zn was assessed by comparing bioaccumulation of these elements in different life stages and frond sizes in samples from three locations, San Vicente Bay (industrial area), Coliumo, and Quidico (the latter as a reference station), where different degrees of heavy metal pollution are recorded. Bioaccumulation and bioconcentration factors of Cd, Cu, Hg, Pb, and Zn were evaluated. The two macroalgae species showed similar patterns, with higher values of Cu, Hg, Pb, and Zn in polluted areas. M. laminarioides bioaccumulated higher concentrations of all metals assessed than S. crispata, independent of life stage and frond size. The results also showed significantly higher Cu, Hg, Pb, and Zn concentrations (p < 0.05) in water samples from San Vicente Bay than those measured in Coliumo and Quidico. Concentrations of Cd, Hg, Pb, and Zn in San Vicente Bay and Cd, Hg, and Pb in Coliumo and Quidico exceed the mean values considered to represent natural concentrations (Cu = 3.00 μg L?1; Zn = 5.00 μg L?1; Pb = 0.03 μg L?1; Cd = 0.05 μg L?1; Hg = 0.05 μg L?1); however, the concentrations recorded do not cause negative effects on the growth and survival of macroalgae. The assessment of heavy metals bioaccumulated in M. laminarioides and S. crispata, particularly Hg, Pb, and Zn, offers a reliable approach for pollution assessment in rocky intertidal environments. Cu and Cd concentrations in seawater samples from San Vicente and Coliumo Bays were significantly higher than in those from Quidico (p value < 0.05); no significant differences in Cd concentrations were observed between San Vicente and Coliumo Bays (p < 0.05). Exceptionally, Cd is bioaccumulated at high levels independent of its availability in the water, thus reaching high concentrations in control areas. High concentrations of metals like Cu and Zn may limit or inhibit Cd uptake in macroalgae, since the transport channels are saturated by some metals, reducing the accumulation of others. These macroalgae species offer good potential for the development of suitable heavy metal pollution survey tools in rocky intertidal environments.  相似文献   

19.
Heavy Metals Monitoring using Bivalves from Mediterranean Sea and Red Sea   总被引:1,自引:0,他引:1  
The concentrations of heavy metals (Cd, Co, Cu, Fe, Mn, Ni, Pd and Zn) were measured in the Bivalves (Modiolus auriculatus and Donax trunculus) collected from the Egyptian coasts of Mediterranean Sea and Brachiodonates sp. from the Egyptian coasts of Red Sea. The average concentrations of the heavy metals analyzed exhibited the following decreasing order: Fe > Zn > Cu > Mn > Ni > Co > Pb > Cd for both Mediterranean Sea and Red Sea. The analyses of Cd, Co, Ni, Pb, and Zn showed higher average concentrations for samples collected from Red Sea than that collected from Mediterranean Sea, while Fe, Cu and Mn showed the reverse results. Fe was used as a normalizing agent for all studied metals and exhibited presence of two locations from each of Mediterranean Sea and Red Sea have anthropogenic inputs of heavy metals. These results suggest that the coastal area in both Mediterranean Sea and Red Sea of Egypt might be considered relatively unpolluted with heavy metal.  相似文献   

20.
This study was conducted to investigate the pollution load index, fraction distributions, and mobility of Pb, Cd, Cu, and Zn in garden and paddy soils collected from a Pb/Zn mine in Chenzhou City, China. The samples were analyzed using Leleyter and Probst’s sequential extraction procedures. Total metal concentrations including Pb, Cd, Cu, and Zn exceeded the maximum permissible limits for soils set by the Ministry of Environmental Protection of China, and the order of the pollution index was Cd > Zn > Pb > Cu, indicating that the soils from both sites seriously suffered from heavy metal pollution, especially Cd. The sums of metal fractions were in agreement with the total contents of heavy metals. However, there were significant differences in fraction distributions of heavy metals in garden and paddy soils. The residual fractions of heavy metals were the predominant form with 43.0% for Pb, 32.3% for Cd, 33.5% for Cu, and 44.2% for Zn in garden soil, while 51.6% for Pb, 40.4% for Cd, 40.3% for Cu, and 40.9% for Zn in paddy soil. Furthermore, the proportions of water-soluble and exchangeable fractions extracted by the selected analytical methods were the lowest among all fractions. On the basis of the speciation of heavy metals, the mobility factor values of heavy metals have the following order: Cd (25.2–19.8%) > Cu (22.6–6.3%) > Zn (9.6–6.0%) > Pb (6.7–2.5%) in both contaminated soils.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号