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1.
Cadmium, zinc and lead concentrations in soils and plants near a smelter at Avonmouth are reported for samples collected in May 1979 and in May 1980. The total metal soil concentrations fall as distance from the smelter increases and decrease rapidly with depth for cadmium and zinc. The concentrations of these two metals are highly correlated at all depths. Near the smelter, where the carbon content and pH values of the soils are lowest, almost all the cadmium, as measured by EDTA extraction, is available. Concentration of metals in plants also decrease with distance from the smelter, with concentrations being lower in samples collected in 1980. This is possibly due to a seasonal variation in biomass, producing a dilution effect. We conclude that uptake of cadmium and that of zinc by grass species have different relationships to the carbon content of the soil.  相似文献   

2.
Freshly deposited surface sediments from the Alexandria coastal zone were collected and analysed in 1995 for their trace metal concentrations. Metal concentrations in the sediments vary between sites within a wide range for copper, zinc, iron, lead, chromium and cadmium. the statistical analysis between the metal concentrations and the different constituents (organic carbon, total nitrogen, silt, clay and total iron) showed significant correlations. the enrichment factors for the sediments ranged between 3 and 4-fold for copper, chromium and zinc and reached up to 9-fold for lead and 113-fold for cadmium. the highest index for cadmium and lead may be attributed to the anthropogenic inputs from the surrounding area, where they are highest in lower discharge areas.  相似文献   

3.
Freshly deposited surface sediments from the Alexandria coastal zone were collected and analysed in 1995 for their trace metal concentrations. Metal concentrations in the sediments vary between sites within a wide range for copper, zinc, iron, lead, chromium and cadmium. the statistical analysis between the metal concentrations and the different constituents (organic carbon, total nitrogen, silt, clay and total iron) showed significant correlations. the enrichment factors for the sediments ranged between 3 and 4-fold for copper, chromium and zinc and reached up to 9-fold for lead and 113-fold for cadmium. the highest index for cadmium and lead may be attributed to the anthropogenic inputs from the surrounding area, where they are highest in lower discharge areas.  相似文献   

4.
A general model TOHM was developed to predict the terrestrial fate of zinc, cadmium, chromium, lead and mercury emitted by the operation of a coal-fired electric generating facility. The general model consisted of interfacing submodels describing atmospheric dispersion, precipitation, soil chemistry, and soil erosion. The models were developed from input data from a semi-arid region of the southwest United States, and except for the climatic and topographic constraints, are not site specific. TOHM was found to predict no substantial increase in indigenous levels of zinc, chromium and lead in the impact (deposition) area. However, both mercury and cadmium were predicted to be emitted and eroded to the environmental sink (receiving lake) in concentrations exceeding that naturally present in the system. TOHM is currently unvalidated, though comparison of soil erosion predictions with erosion quantities measured in the impact area gives good agreement.  相似文献   

5.
The levels of lead and cadmium were determined in deciduous teeth of children from different areas of Northrhine-Westfalia, Germany. The children were born in 1968–1973 and 1979–1986. The levels of lead and cadmium in deciduous teeth show a significant decrease within this time interval. Lead decreases about 50 %, cadmium about 60 %. Since tooth lead and tooth cadmium may be used as indicators of the lead and cadmium body burden, the results of this study indicate a significant decrease of population exposure to lead and cadmium in West-Germany during the past 20–25 years, which is a consequence of pollution control and the increasing use of unleaded fuel.  相似文献   

6.
The net uptake of zinc, cadmium, lead and copper by the common mussel Mytilus edulis (L.) exposed to different conditions was investigated with a view to using this species as an indicator of contamination of the marine environment by these metals. The variables studied were season, position of the mussel in the water column, water salinity, water temperature, and the simultaneous presence of all four metals. Each of these 5 variables affected the net uptake of some or all of the metals studied under some conditions. Seasonal variation in concentrations of zinc, cadmium and copper was found in samples collected at three separate locations. The relationship of seasonal variation to tissue weight and absorption route of the metals is discussed. Near to freshwater inputs of trace metals, the concentrations of zinc, cadmium and lead in mussels were found to vary according to the depth at which the mussels were collected; in summer when freshwater run-off is less, this effect was absent. Low salinities did not affect the net uptake of zinc by mussels, but increased the net uptake of cadmium and decreased that of lead. Low temperatures had no effect on the net uptake of zinc or lead; the net uptake of cadmium was unaffected by low temperatures at high salinities but was decreased by low temperatures at low salinities. The presence of the other metals had no effect on the individual net uptake of either zinc, cadmium or lead. A sampling programme was devised to eliminate the effects of these environmental variables and to allow the use of M. edulis as an indicator of zinc, cadmium and lead in marine and estuarine environments. In contrast to the other metals, the net uptake of copper by the mussel was extremely erratic, and was affected by salinity and temperature changes and by the presence of the other metals and changes in their relative concentrations. The effects of other metals on the net uptake of copper cannot be easily eliminated or allowed for; it is, therefore, suggested that the mussel should not be used as an indicator of copper in the marine environment.  相似文献   

7.
Lead and cadmium concentrations in spontaneous vegetation and in soil sampled at various distances (0–208 m) from several motorways throughout Italy were measured. Lead and cadmium concentrations appear to be correlated to distance from the motorway and to traffic levels. A comparison with data from a remote and unpolluted site shows that foliar lead concentrations can be up to 40 times higher, and foliar cadmium concentrations up to 3 times higher. Plants behave differently in their accumulation of lead and cadmium; conifers present the highest levels. Also the various receptors and compartments of the roadside ecosystem differ in their accumulation of lead and cadmium; soil and bark have consistently higher concentrations, while the leaves and twigs of trees have consistently lower levels. the data recorded by ad hoc introduced bio-accumulating plants (Lolium multiflorum L.) are consistent with those of the spontaneous vegetation. the concentrations of both lead and cadmium in Lolium vary from June to November, following in part the fluctuation in traffic density.  相似文献   

8.
Concentrations of zinc and cadmium in whole soft parts of mussels, Mytilus edulis (L.), collected from 54 locations in Scandinavian waters were determined. Local variations in concentrations of the two metals found in samples taken close to industrial sources of zinc and cadmium confirmed the ability of the mussel to act as an accurate indicator of pollution by these metals over the entire range of salinities in which this species can exist. In addition, offshore samples remote from industrial discharges revealed higher concentrations of zinc and cadmium in mussels from lowsalinity areas (Gulf of Finland, Southern Bothnian Sea, Baltic proper) than in those from high-salinity areas (Kattegat, Eastern Skagerrak). Major decreases in metal concentrations present in the mussel were apparent in the regions of the Sound and the Great Belt, which are areas of rapid salinity change due to mixing of Baltic water with water from Kattegat. Comparison of these results with those reported for zinc and cadmium in water throughout the study area suggested the existence of a higher biological availability of these metals in regions of low salinity; possible reasons for this are discussed. Data from the present survey are also compared to those reported for mussels taken elsewhere. This comparison reveals the Baltic area to be considerably polluted by trace metals; in contrast, the waters of Kattegat and skagerrak are considered to be relatively unpolluted.  相似文献   

9.
Benthic organisms revealed enhanced uptake of mercury from polluted surface sediments (in the vicinity of a chlor‐alkali plant) which were enriched in mercury by up to 148 times relative to sediments from an unpolluted area. There is a strong correlation between the concentrations of mercury in the benthic organisms and sediments. No correlation was found between cadmium, lead, copper and zinc levels in the benthic fauna populations and the concentrations of these metals in the sediments. Ranges of concentrations (μg/g wet wt.) in the whole soft tissues varied: Hg, <0.005–3.31; Cd <0.018–1.99; Pb, <0.025–1.56; Cu, 0.242–28.8; and Zn, 9.75–310.2. The three gastropod molluscs show higher metal concentrations than do the bivalves.  相似文献   

10.
为探讨深圳市农林土壤重金属的污染现状,系统采集了深圳市菜地、果园、林地和荒地4种土地利用的52个土壤样品,测定了Cu、Pb、Cd、Zn、Cr、Ni6种重金属的全量,对深圳市农林土壤重金属20余年来的累积状况进行了分析并进行了初步的风险评价.结果发现,深圳农林土壤均存在不同程度的重金属累积,总体而言,Cu、Pb、Zn、Cr和Ni的累积较轻,Zn的最大含量尚未超过其80年代末背景值的最大值;Cd的累积最为严重,其最大含量已为背景最大值的16倍.以GB15618-1995为标准,对深圳农林土壤的重金属风险进行评价后发现,Cu的污染最轻,仅20%的菜地土壤超过国家一级标准,Pb50%超过国家一级标准,但尚未超过二级标准;Zn、Cr和Ni均有一定比例的样点超过二级标准,最少4%,最高50%,但未有超过三级标准的样点;Cd的风险最大,不仅有大量超过一、二级标准的样点,而且超过三级标准的样点也占有一定的比例(菜地、果园、林地和荒地土壤中Cd含量超过三级标准的比例分别为10%、23%、29%和50%).深圳农林土壤中的Cd污染应该引起相关部门的重视.  相似文献   

11.
Concentrations of mercury, cadmium, copper, zinc and iron were determined in the carapace, hepatopancreas, gills, tail muscle, ovary and eggs of 288 Norway lobsters, Nephrops norvegicus, caught in the Clyde Sea area, south of the Isle of Cumbrae, Scotland. Metal levels in males and females were examined separately in relation to size and the season in which the animals were caught.

Cadmium, copper and zinc concentrations were highest in the hepatopancreas whereas mercury and iron concentrations were highest in the gill. Levels of metals showed variations between months, with highest levels tending to occur during molt. Metal levels were influenced by lobster size with pronounced size-related increases in mercury levels in the tail muscle and cadmium levels in the hepatopancreas. Levels of several metals in the various tissues differed between the sexes.  相似文献   

12.
Nitrogen fixation by free-living non-symbiotic bacteria has been qualitatively estimated in several surface soils and mine wastes from mineralised areas in Derbyshire and Cornwall, using a technique based on acetylene reduction. Fresh samples contaminated with varying amounts of one or more of the metals lead, zinc, cadmium and copper, together with appropriate controls, showed no ability to reduce acetylene, indicating an absence of nitrogen fixation. Addition of activeAzotobacter chroococcum resulted in acetylene reduction in the majority but not all of the samples. The effects of varying concentrations of lead, zinc, cadmium and copper on the growth ofAzotobacter chroococcum andBeijerinckia lactogenes were tested in laboratory culture.  相似文献   

13.

Goal and Scope

This study was undertaken to investigate the differences in heavy metal burden between the organisms and environmental compartments and to evaluate the role of Dreissena polymorpha as a bioindicator organism.

Methods

The concentrations of zinc, copper, cadmium and lead in whole soft body and selected tissues of D. polymorpha at two river habitats in Austria were examined using atomic absorption spectroscopy (AAS). Concentrations in organisms were compared to those in sediment and water.

Results and Conclusion

Zebra mussels of the river Drau showed generally higher heavy metal concentrations as compared to mussels of the river Danube and contained elevated zinc and cadmium levels as compared to metal concentrations found in soft tissues of zebra mussels from uncontaminated sites in Germany and The Netherlands. The essential metals zinc and copper were mainly accumulated in gills, foot and byssal gland tissue of the mussel, in contrast to the non-essential metals cadmium and lead which were found predominantly in the midgut gland. The heavy metal concentrations in both, sediments and mussel tissue, were higher than in water samples. There was no correlation between the concentrations in water and in the organisms except for zinc. In contrast, correlations were found between concentrations in sediments and mussel soft tissue.

Recommendation and Perspective

Further investigations should include the examination of sediments and consider the mechanism of food uptake to assess the role of D. polymorpha as a bioindicator organism.  相似文献   

14.
The kilns used to manufacture Portland cement provide an excellent environment for the safe disposal of certain combustible, hazardous wastes. Moreover, the fuel value of these wastes may yield significant savings in fuel costs.In order to evaluate part of the air pollution potential associated with these fuels, spent solvents were analyzed for trace metals using flame atomic absorption spectroscopy. Lead, zinc, chromium, nickel, selenium, cadmium, beryllium and arsenic levels were examined in 55 samples of solvents that had been obtained by a single distillation of unblended spent solvents, 185 samples of undistilled solvents, and 10 samples of coal. All samples of distilled solvents showed metal concentrations near the limit of detection.The mixed, undistilled solvents showed metals concentrations that were relatively higher than the distilled product, and very scattered except for cadmium, beryllium and arsenic, which were always below the limit of detection. The average values (mg/l) for lead, zinc, chromium, nickel and selenium were 42, 58, 30, 14 and 4, respectively.In order to determine the potentialnet increase or decrease of trace metals in the stack gases, ten coal samples were tested. These coal samples were obtained from a nearby cement kiln. The average concentrations for coal were 20 mg/l lead, 38 mg/l zinc, 43 mg/l chromium (corrected), 60 mg/l nickel 2 mg/l beryllium, and <0.62 mg/l cadmium. No determinations were made for selenium and arsenic. Most of the metal content of the spent solvents was contained on or in the participate matter in the solvents. It follows that the supernatant liquid from a settling tank should be a relatively safe fuel for use at cement kilns.  相似文献   

15.
云南临沧地区公路两侧紫茎泽兰分布格局   总被引:6,自引:0,他引:6  
云南省临沧地区是我国紫茎泽兰(Eupatorium adenophorum)传入最早和入侵危害最严重的地区。文章在该地区选取典型路段并设置了10个样地,以等级、路宽、路面状况、路龄、人类活动干扰不同的7条公路为研究对象,分析了紫茎泽兰生物量、株高和株数与距公路距离、公路宽度、景观类型、坡向及海拔的关系。结果表明,公路对紫茎泽兰生物量和株高有显著影响的最远距离为24m,而对株数的影响达34m;6m宽的公路对紫茎泽兰生物量和株数影响最显著,且路龄越长、交通干扰越大的公路两侧的紫茎泽兰入侵危害越严重;紫茎泽兰在公路附近的撂荒地和次生林两个景观类型中入侵危害严重,景观类型对生物量与坡向对株高的影响不显著,位于南坡公路附近的紫茎泽兰生物量和株数最高,研究发现公路附近紫茎泽兰总生物量随海拔升高而增加,在1700m达最大,随后则降低。  相似文献   

16.
The present paper examines the degree of environmental contamination in areas covered by the Natura 2000 programme, located in north-western Poland, with selected heavy metals based on their concentration in target organs of roe and red deer. Lead, cadmium, copper, iron, and zinc concentrations were determined by inductively coupled plasma–atomic emission spectrometry. Residues of lead and cadmium were found in most of the analysed samples of roe and red deer organs The concentration of cadmium in the organs of the animals studied was much higher than that of lead. The median for Pb in liver and kidneys was 0.055 and 0.092 μg/g dry weight (d.w.) in roe deer, and 0.067 and 0.081 μg/g d.w. in red deer, respectively. The median for liver and kidney cadmium was 0.770 and 6.139 μg/g d.w. in roe deer, and 0.422 and 6.365 μg/g d.w. in red deer, respectively. Our study has demonstrated that this area is laden with lead and cadmium. This is evidenced by the fact that maximum permissible levels of these elements in the organs of red and roe deer, which were used as bioindicators of environmental contamination, were exceeded.  相似文献   

17.
The zinc, cadmium, copper and lead release from the uncontaminated and contaminated coastal sediments with aerated sea water was studied. the metals transfer to the dissolved forms was monitored during one-two months by differential pulse anodic voltammetry (DPASV). the sediments with different initial degree of contamination were sampled in the Peter the Great Bay, Sea of Japan around Vladivostok-the biggest city in Russian Far East. Sediment contamination by metals led to increased release to solution of zinc due to sulphide oxidation and cadmium on account of organic matter decomposition. the copper behaviour was complicated by strong binding with organic matter and enhancements of copper release can only be seen in sediment with a low organic matter content. Significant lead transfer to dissolved forms was not observed regardless of sediment contamination. the temperature affected the release of cadmium and copper through enhanced organic matter destruction. the dissolved metal fluxes from the sediment transformation are compared with metal fluxes towards bottom. Such comparisons show that second contamination by dissolved metals of the studied coastal environment may be important for cadmium only.  相似文献   

18.
The zinc, cadmium, copper and lead release from the uncontaminated and contaminated coastal sediments with aerated sea water was studied. the metals transfer to the dissolved forms was monitored during one-two months by differential pulse anodic voltammetry (DPASV). the sediments with different initial degree of contamination were sampled in the Peter the Great Bay, Sea of Japan around Vladivostok-the biggest city in Russian Far East. Sediment contamination by metals led to increased release to solution of zinc due to sulphide oxidation and cadmium on account of organic matter decomposition. the copper behaviour was complicated by strong binding with organic matter and enhancements of copper release can only be seen in sediment with a low organic matter content. Significant lead transfer to dissolved forms was not observed regardless of sediment contamination. the temperature affected the release of cadmium and copper through enhanced organic matter destruction. the dissolved metal fluxes from the sediment transformation are compared with metal fluxes towards bottom. Such comparisons show that second contamination by dissolved metals of the studied coastal environment may be important for cadmium only.  相似文献   

19.
The relations between genetic variation, physiological condition, size and metal status in the shore crab Carcinus maenas (L.) were investigated. Shore crabs were collected at three sites around the island of Funen, Denmark, and carapace width, colour, moulting stage and major ions and protein in the haemolymph were determined. Concentrations of water, cadmium, copper and zinc in midgut glands, muscles and gills were measured, and allozyme variation at 15 loci was studied. Generally, tissue water content and copper, zinc and cadmium concentrations decreased from the moulting stages C3 over C4 to D crabs, whereas the opposite was true for copper and zinc concentrations in gills and muscle. However, the water content of the tissues increased with the size of the crabs. Since tissue water contents changed consistently over moulting stages, conclusions on changes in metal concentrations sometimes diverged when expressed on a dry versus wet weight basis. Regarding allozymes, esterase, malate dehydrogenase and phosphoglucomutase were polymorphic. The crabs showed a low level of genetic variability for both polymorphism (0.14) and for heterozygosity (0.07) at the three sites. Allelic frequencies showed very low levels of differentiation among the samples, no evidence of inbreeding and no population subdivision. Multilocus heterozygosity was positively correlated with size. Concentrations of copper and zinc in midgut gland, muscle tissue and gill were not correlated with genotype, whereas a weak correlation between phosphoglucomutase genotypes and concentrations of cadmium in the midgut gland was found.Communicated by M. Kühl, Helsingør  相似文献   

20.
Surface and profile Phaeozem soil samples from 31 locations affected by various anthropogenic activities such as mining, chemical manufacturing, traffic emission and pesticide application were collected in Heilongjiang Province and Jilin Province, northeast China. The range of total concentrations of four heavy metals Cd, Pb, Cu and Zn in the soil was 0.011–3.137, 10.31–62.34, 9.74–51.21 and 39.54–247.59 mg kg−1, respectively, determined using the acidic digestion procedure. Four methods including single contamination evaluation, background concentration comparison, surface/subsurface concentration comparison and exchangeable fraction evaluation were used to evaluate the extent of metal contamination in Phaeozem. The results indicated that different activities increased the concentrations of the heavy metals in surface soils, where high concentrations of cadmium and lead were found close to chemical plants and in the suburbs of the investigated cities. The four methods showed a general trend of increased soil contamination with heavy metals. Cadmium was of the most concern compared with the other contaminated elements in the study area, due to the long-term phosphatic fertilizer utilization and industrial activities. The proper evaluation method for cadmium contamination was the background concentration comparison, while for zinc and copper was the single contaminative index evaluation. Cadmium and lead could be the potential environmental risk in the Phaeozem area based on the different evaluations.  相似文献   

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