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1.
Aerosol samples were collected at two coastal suburban stations, Qingdao (China) in 1995-1996 and Liverpool (U.K.) in 1995, respectively. The samples were analyzed to determine the concentrations of trace metals (Cr, Zn, Cu, Co, Ni, Pb, V, and Cd) as well as A1, Fe and Mn. Data were examined to understand the difference of trace metals in aerosols between coastal zones downwind the developing area (near the Yellow Sea) and developed region (near the Irish Sea). The results show that most elements at Qingdao have levels 4-5 times higher than those at Liverpool, particularly for the crust-dominated elements (e.g. Al, Fe and Mn). Moreover, the aerosol composition at Qingdao is higher in spring than in summer, underlying the influence of westerlies and local emissions in combination, whereas seasonal change of aerosol composition is not significant at Liverpool. The enrichment factors for the crustal source elements (EFcrust) at Liverpool are much higher than those at Qingdao. The contributions from the pollutant source (Rp) for some trace metals like Cu, Pb, Zn and Cd are 〉90% at Qingdao and Liverpool, suggesting overwhelming anthropogenic contributions to these metals. The contributions from crustal source (Re) for trace metals tend to increase with higher aerosol levels and Al concentration at Qingdao, indicating a good correlation between the crust-dominated component and the air mass. At Liverpool, the Rc values for trace metals are positively correlated with Al concentrations instead of with aerosol mass, suggesting that Al in aerosols represents the crustal component even though the aerosols come from different sources.  相似文献   

2.
The distribution of trace metals in remote alpine region is an effective way to understand the impacts of regional human activity and vegetation on the alpine ecosystem. In this study, the concentrations of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the soils of Gongga Mountain, Eastern Tibetan Plateau, were investigated to reveal their seasonal and spatial distribution and enrichment state, and to decipher the effects of atmospheric deposition and vegetation on their distributions among five vegetation zones. The results showed that the concentrations of Cd, Pb, and Zn were higher in the O horizon than in other horizons despite the seasonal changes, whereas Cu was enriched in the C horizon. The enrichment states of the metals studied in the soils decreased in the order of Cd > Pb > Zn > Cu. Cd and Pb were mainly sourced from atmospheric deposition; Zn was from both atmospheric deposition and parent materials, whereas Cu was mainly from parent materials. Seasonally, the trace metals were generally higher in May and December but lower in September, implying the impact of vegetation on the distribution of trace metals under the plant uptake and the litter decomposition. Spatially, the higher enrichment of Cu, Pb, and Zn in the soils existed in the mixed broadleaf-coniferous forests and coniferous forests (approximately 3000 m above sea level). The results suggested that atmospheric deposition and biological processes are main factors controlling the seasonal and spatial distribution of trace metals in the soils of the remote alpine ecosystem.  相似文献   

3.
This paper reported the results of the determination of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (0-10 cm) underneath the fruiting bodies. Mushrooms and soils were collected from a lowland site in the Hel Peninsula (Baltic Sea coast) and a high mountain site in the Tatra Mountains. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES). Common Chanterelles that emerged at sites poor in mineral nutrients podzols of the Hel Peninsula forests efficiently bioconcentrated several essential trace elements (K, P, Co, Cu, Mn, Na, Zn), while the abundance of those elements in carpophores was around half less compared to specimens from Zakopane region and which emerged in soils much richer in minerals. Common Chanterelles collected at two spatially distant background areas in Poland were only weakly contaminated with metals such as Ag, Cd, Hg and Pb. The maximum tolerable Cd and Pb contents of certain cultivated mushrooms are regulated in the European Union by law and these hazardous metals in C. cibarius were far below tolerance limits set.  相似文献   

4.
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   

5.
Episodic deposition has been recognized as a major factor affecting the decomposition rate of detrital material in salt marshes. In this paper, three one-off burial treatments, no burial treatment(0 cm, NBT), current burial treatment(10 cm, CBT) and strong burial treatment(20 cm, SBT), were designed in intertidal zone of the Yellow River Estuary to determine the potential influences of episodic deposition on nutrient(C, N) and heavy metal(Pb, Cr, Cu, Zn, Ni, Mn, Cd, V and Co) variations in decomposing litters of Suaeda glauca. Results showed that although various burial treatments showed no statistical difference in decomposition rate of S. glauca, the values generally followed the sequence of CBT(0.002 403/d) SBT(0.002 195/d) NBT(0.002 060/d). The nutrients and heavy metals in decomposing litters of the three burial treatments exhibited different variations except for N, Cu, Cr, Ni and Co. Except for Mn, no significant differences in C, N, Pb, Cr, Cu, Zn, Ni, V and Co concentrations occurred among the three treatments(P 0.05). With increasing burial depth, Cr and Cd levels generally increased while Cu, Ni and Mn concentrations decreased. Although episodic deposition was generally favorable for C and N release from S. glauca, its influence on release was insignificant. In the three burial treatments, Pb, Cr, Zn, Ni, Mn, V and Co stocks in S. glauca generally evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. The S. glauca were particular efficient in binding Cd and releasing Pb, Cr, Zn, Ni, Mn, V and Co, and, with increasing burial depth, stocks of Cu in decomposing litters generally shifted from release to accumulation. The experiment indicated that the potential eco-toxic risk of Pb, Cr, Zn, Ni, Mn, V and Co exposure would be serious as the strong burial episodes occurred in S. glauca marsh.  相似文献   

6.
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   

7.
Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium(Cr), copper(Cu), molybdenum(Mo), manganese(Mn), lead(Pb), tin(Sn), titanium(Ti), vanadium(V), and yttrium(Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea(SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events.  相似文献   

8.
Based on the field data obtained during cruises on the shelf of the East China Sea from 1997 to 1999, seasonal variations of coastal upwelling on the inner shelf are discussed by using cross-shelf transect profiles and horizontal distributions of chemical and hydrographic variables. Results show that the coastal upwelling was year-round, but the areas and intensities of the upwelling were quite different in season. The coastal upwelling occurred in all of the coastal areas of the region in spring and summer, but in autumn only in the area off Zhejiang Province, and in winter in the area off Fujian Prov- ince. It was the strongest in summer and the weakest in winter. Geographically, it was the strongest in the area off Zhejiang Province and the weakest in the southmost or northmost parts of the East China Sea. The estimated nutrient fluxes upward into euphotic zone through coastal upwelling were quite large, es- pecially for phosphate, which contributed significantly to primary production and improved the nutrient structure of the coastal ecosystem in the East China Sea.  相似文献   

9.
Aerosol samples were collected with a Sierrer Model 235 cascade impactor in the marine atmosphere over the Kuroshio area in consecutive four seasons from 1987 to 1988. Na, G, Al, V, and water soluble and acid soluble Mn, Fe, Pb, Cu, V, Cd were determined by neutron activation analysis and atomic absorption spectrophotometry, respectively. Seawater source chemical species in the aerosols appeared in high content in large over 3.6um diameter particles, and crustal source vanadium appeared in 3.6um diameter particles, but pollution source vanadium appeared in less than 0.52um diameter particles. Trace metals in the aerosols mostly had the highest concentration of water soluble metals on fine particles, and acid soluble metals on large particles. The concentrations of trace metals in the aerosols were higher in autumn and winter, lower in spring and summer.  相似文献   

10.
Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium (Cr), copper (Cu), molybdenum (Mo), manganese (Mn), lead (Pb), tin (Sn), titanium (Ti), vanadium (V), and yttrium (Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea (SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events.  相似文献   

11.
Aerosol samples were collected with a Sierrer Model 235 cascade impactor in the marine atmosphere over the Kuroshio area in consecutive four seasons from 1987 to 1988. Na, Cl, Al, V, and water soluble and acid soluble Mn, Fe, Pb, Cu, V, Cd were determined by neutron activation analysis and atomic absorption spectrophotometry, respectively. Seawater source chemical species in the aerosols appeared in high content in large over 3.6 μm diameter particles, and crustal source vanadium appeared in 3.6 μm diameter particles, but pollution source vanadium appeared in less than 0.52 μm diameter particles. Trace metals in the aerosols mostly had the highest concentration of water soluble metals on fine particles, and acid soluble metals on large particles. The concentrations of trace metals in the aerosols were higher in autumn and winter, lower in spring and summer. Funds from the National Natural Science Foundation of China.  相似文献   

12.
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   

13.
Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. Results revealed that the contents of elements (e.g., Fe, Mn, Cu, Zn, V, Co) were high in samples 22V-TVG10 and 26V-TVG05 from the sites near the hydrothermal areas, and low in sample 22V-TVG14, which was collected far from the hydrothermal areas. The contents of Ca, Sr and Ba in the samples showed opposite trends. A positive correlation between the concentrations of metallic elements (Cu, Zn, Co, Ni, Pb, V) and Fe in the samples were observed. These results are consistent with chemical evolution of the dispersing hydrothermal plume.  相似文献   

14.
In this paper, systematic studies on the changes in concentrations of the environmental factors and the net-phytoplankton community, and the relationship between them in the Liaodong Bay, Bohai Sea during 2013 are presented. The PCA results showed that higher levels of nutrients and dissolved heavy metals in the river-estuary-bay system were closely related to the river runoff. Since the influences of industrial and anthropogenic activities, the Liaodong Bay coastal areas are facing a huge environmental challenge of nutrients and heavy metal pollution. Net-phytoplankton community structure showed obvious seasonal succession, among which the dominant and (or) key species were the main factors affecting community structure change and stability. Under certain environmental conditions, the dominant species and (or) key species dominated the phytoplankton community structure succession. The Bio-ENV results suggested that the seawater temperature, nutrient, Cu, Pb, Zn, and Cd in Liaodong Bay are important environmental variables that affect the phytoplankton community structure. Anthropogenic activities have significantly contributed to the changes in concentrations of environmental factors and the net-phytoplankton community structure and stability, and the relationship between them.  相似文献   

15.
Concentrations of the trace metals Cu,Cd,Pb,and Zn were measured in seawater,rhizosphere sediments,interstitial water,and the tissues of three tropical species of seagrasses (Thalassia hemprichii,Enhalus acoroides and Cymodocea rotundata) from Xincun Bay of Hainan Island,South China.We analyzed different environmental compartments and the highest concentrations of Pb and Zn were found in the interstitial and seawater.The concentrations of Cd and Zn were significantly higher in blades compared with roots or rhizomes in T.hemprichii and E.acoroides,respectively.A metal pollution index (MPI) demonstrated that sediment,interstitial water,and seagrasses in the sites located nearest anthropogenic sources of pollution had the most abundant metal concentrations.There was obvious seasonal variation of these metals in the three seagrasses with higher concentrations of Cu,Pb and Zn in January and Cd in July.Furthermore,the relationships between metal concentrations in seagrasses and environmental compartments were positively correlated significantly.The bioconcentration factors (BCF) demonstrated that Cd from the tissues of the three seagrasses might be absorbed from the sediment by the roots.However,for C.rotundata,Zn is likely to be derived from the seawater through its blades.Therefore,the blades of T.hemprichii,E.acoroides and C.rotundata are potential bio-indicators to Cd content in sediment,and additionally Zn content (C.rotundata only) in seawater.  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.
Abstract Zinc (Zn) and copper (Cu) concentrations were determined in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five commercial fish species (mullet Liza haematocheilus, flathead Platycephalus indicus, mackerel Scomberomorus niphonius, silver pomfret Pampus argenteus, and sea bass Lateolabrax japonicus) from Laizhou Bay in the Bohai Sea. Metal bioaccumulation was highest in the metabolically active tissues of the gonads and liver. Bioconcentration factors for Zn were higher in all tissues (gonads 44.35, stomach 7.73, gills 7.72, liver 5.61, skin 4.88, and muscle 1.63) than the corresponding values for Cu (gonads 3.50, stomach 3.00, gills 1.60, liver 5.43, skin 1.50, and muscle 0.93). Mackerel tissues accumulated metal to higher concentrations than did other fish species, but bioaccumulation levels were not significantly correlated with the trophic levels of the fish. Zn and Cu concentrations in the tissues were generally negatively correlated with fish length, except for a few tissues of sea bass. Risk assessment based on national and international permissible limits and provisional tolerances for weekly intake of Zn and Cu revealed that the concentrations of these two metals in muscle were relatively low and would not pose hazards to human health.  相似文献   

18.
INTRODUCTIONTheYellowSeaandtheEastChinaSea (ECS)aremarginalseasofthenorthwestPacificandhaveexpansivecontinentalshelves .TheuniqueandstrikingfeaturesoftheYellowSeaandtheECSarethattheyhavestrongtidalcurrent;aresubjecttostrongmonsooninfluence ;andreceiveinflowfromthebiggestriverinChina ,theChangjiangRiver ;andthatthefamouswesternboundarycurrent,theKuroshio ,passesthroughtheECS ,withitsbranchesintrudingupwardintothecontinentalshelfareas.Generallyspeaking ,thewaterexchangecapacityofthe…  相似文献   

19.
In the current study, we determined concentrations and transfer rates of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn to Brown Birch Scaber Stalks (Leccinum scabrum) mushrooms emerged in the area of Sudety Mountains (Sudetes) in Poland. Fruiting bodies and topsoil samples beneath L. scabrum were collected form the K odzka Dale. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES) for final measurement. Mushrooms contained Ag, Cr, Hg, Co, Ni and Sr at < 1.0 μg/g dry weight; Ba and Pb at ~1.0 μg/g dw; Cd at < 5 μg/g dw; Cu and Mn at > 10 μg/g dw; Al and Ca at ~100 μg/g dw; Fe, Na, Rb and Zn at 100 to 500 μg/g dw, Mg at ~1,000 μg/g dw; P at ~5,000 μg/g dw and K at ~30,000 μg/g dw. Ca, Mn and Ni were nearly equally distributed between stipes and caps; stipes compared to caps were enriched in Ba, Na and Sr, while caps were enriched in Ag, Al, Cd, Co, Cr, Cu, Fe, K, P, Pb, Rb and Zn. The values of bioconcentration factor (BCF) varied highly depending on chemical element and were >1 for Ag, Cd, Cu, K, Mg, Na, P, Rb and Zn, while <1 for Al, Ba, Ca, Co, Cr, Fe, Mn, Ni, Pb and Sr. Topsoil showed elevated content of lead and mean concentration was 99 ± 32 μg/g dw, while cadmium was at 0.41 ± 0.15 and those two highly toxic to human elements occurred in edible caps of L. scabrum at 4.5 ± 2.2 and 2.9 ± 2.0 μg/g dw, respectively.  相似文献   

20.
A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sediment samples using fused glass disc by X-ray Fluorescence spectrometry. Calibration was made using marine sediment certified reference materials and the synthetic standard samples prepared by mixing several marine sediments with stream sediment and carbonate standard samples in different proportions. The matrix effect was corrected using theoretical alpha coefficients, experience coefficients and the scattered radiation as the internal standard (for the trace elements). The accuracy of the method was evaluated by analysis of certified reference materials GBW07314, GBW07334 and GSMS6. The results are in good agreement with the certified values of the standards with RSD less than 2.60%, except for Y, Cr, Ga, Ce, La, Nb, Rb, and V with RSD less than 9.0% (n=12).  相似文献   

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