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1.
Hypogymnia physodes (L.) Nyl. andDicranoweisia cirrata (Hedw.) Lindb. were transplanted to 12 stations in the vicinity of the steelworks in Frederiksvaerk, Denmark. The transplants were exposed for 7 mo, and samples were taken after 31, 64, 104, 154, 184, and 214 days. Bulk precipitation was collected simultaneously. The concentrations of the metals Cd, Cr, Cu, Fe, Mn, Ni, Ph, V, and Zn were analyzed by atomic absorption spectrophotometry in both transplants and bulk precipitation. The amounts of accumulated metals in the transplants were linearly correlated with fallout from the atmosphere, the bryophytes accumulating the metals slightly faster than the lichens. The metal concentrations in the transplants, as well as the bulk precipitation, followed a decreasing power curve when the distance to the steelworks was increased. It was concluded that transplanted lichens and bryophytes can be applied as monitor organisms of heavy metal pollution from the air.  相似文献   

2.
Mosses, lichens and pine bark were compared as indicators of atmospheric heavy metal deposition in Finland. The samples were collected from the nationwide sampling network systematically covering the country as a whole. All three bioindicators showed a fairly similar result concerning heavy metal deposition. The major emission sources and the areas affected were reflected in the metal concentrations in the samples. However, there were differences between the accumulation of metals. The correlation between concentrations in mosses and lichens was generally higher than that between mosses and bark or lichens and bark. Concentrations in lichens were the highest and lichens reflected the regional differences in background areas as well as the local emission sources. The concentrations in the mosses were slightly lower than those in lichens and also the mosses pinpointed the emission sources and the extend of the areas polluted. Bark had the lowest concentrations and bark did not generally reveal regional differences as well as mosses and lichens. In spite of the differences, all three bioindicators proved to be suitable for monitoring atmospheric heavy metal deposition.  相似文献   

3.
Metal processing at a Cu-Cd refinery at Prescot in N.W. England has led to severe contamination of the surrounding soils and vegetation, although Cu and Cd in bulk deposition declined dramatically between 1975 and 1990. Despite high spatial and temporal variability in metal deposition, mean Cd concentrations in annual tree rings of sycamore (Acer pseudoplatanus L.), lime (Tilia europaea L.) and beech (Fagus sylvatica L.) at Prescot were correlated with annual bulk Cd deposition. In contrast, mean Cd concentrations in ash (Fraxinus excelsior L.) were unrelated to Cd deposition and there was no significant relationship between mean Cu concentrations in tree rings and Cu deposition in any species. Mean Pb concentrations in sycamore, lime and beech at Prescot and the reference site also decreased over time. At Prescot however, Cd concentrations in tree rings formed in the mid 1990s were up to 10-fold higher than the reference site despite Cd deposition values during this period that were typical of levels expected for urban areas in the UK. The high Cd concentrations in wood during this period indicate that the majority of Cd in tree rings at Prescot is derived from soil, limiting the usefulness of dendrochemistry for monitoring temporal changes in metal deposition. It appears that trees are not simply passive recorders of metal deposition and other possibilities, in addition to decreasing atmospheric deposition, may explain the patterns of Cd and Pb found in sycamore, lime and beech. More research on the physiology of metal cycling in trees is required before dendrochemical techniques can be applied with confidence in environmental monitoring programs.  相似文献   

4.
The lichens Ramalina stenospora and Parmotrema praesorediosum were collected from 30 stations in the greater metropolitan area of Baton Rouge, Louisiana and analyzed for Al, Cu, Fe, Zn, and Pb content. A univariate analysis of the data showed a significant difference between metal concentrations and sampling stations. When the stations were separated into two groups representing those in the industrial and urban zones, a discriminant analysis was over 90% successful in correctly assigning stations based solely on metal concentrations. No significant differences in metal concentration with species could be observed. Average metal concentrations for the two lichen species were used to construct contours and three-dimensional plots of metal distribution across the study area which clearly demonstrate the effects of the industrial zone on airborne metal levels.  相似文献   

5.
Development of heavy-metal deposition by precipitation in West Germany. 1. Lead and cadmium Between 1984 and 1993 the deposition of Pb and Cd with bulk precipitation was measured on 25 open field sites in 4 German federal states. The absolute amount of Pb and Cd deposition varies according to field sites and annual precipitation. In all studied areas, however, Pb deposition via bulk precipitation decreased significantly during the observation period. Considering all research areas under study, the average Pb deposition with bulk precipitation fell from 142 g ha?1 in 1984 to 31 g ha?1 in 1993 (r = ?0.934***). This decrease in Pb deposition correlates with the prognosticated decline in Pb emissions that occurred in Germany during the same time period owing to the introduction of unleaded motor fuels in 1984. Average Cd deposition on all research stations fell from 3.4 g ha?1 in 1984 to 2.0 g ha?1 in 1993 (r = ?0.900***). However, in contrast to Pb, the reduction of Cd deposition was significant only at 11 of 25 research stations. The reduction in Cd deposition with precipitation is substantially lower than the reduction in Cd emissions prognosticated.  相似文献   

6.
Local variability in the heavy metal concentrations of precipitation and seepage water from forest sites in the Solling Concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb in precipitation and seepage water have been measured continuously with local replicates during a 6-months period at a beech and a spruce forest site. Variation coefficients of the avarage concentrations were, in most cases, well below 30 %, being mainly caused by local differences. Comparison of means showed a significant increase of heavy metal concentration in the canopy drip of beech (Mn, Fe, Pb) and spruce (Cr, Mn, Fe, Ni, Zn, Pb) compared to bulk precipitation measured in the open field. Concentration of Mn, Co, Ni, Zn and Cd in the seepage water is significantly higher under spruce compared to beech. These results point at higher filter efficiency of the spruce canopy, compared with beech, for air pollutants, but a smaller retention capacity of the soil under spruce for heavy metals.  相似文献   

7.
Concentrations of Cd, Cu, Ni, Pb and Zn were determined in bulk atmospheric deposition collected at five stations in the Seine River basin (France), to evaluate sources and fluxes of atmospheric trace metals. Bulk deposition (wet + dry) was sampled weekly from March 2001 to February 2002 for 4 sites and from March to December 2001 for the last one. The concentrations of the elements in bulk deposition (dissolved + particulate form) followed the order: Zn > Pb > Cu > Ni > Cd. Concentrations of Zn, Pb and Ni were highly correlated with one another, suggesting a common source, related to the combustion of coal and heavy fuel. Metal concentrations in bulk deposition did not exhibit a high degree of temporal variability over the annual cycle and were not obviously related to meteorological parameters (rainfall, wind). Estimates of the total annual direct atmospheric deposition of metals to the Seine Estuary ranged from 16 kg yr? 1 for Cd to 5600 kg yr? 1 for Zn. Loadings of Cd, Cu and Ni from direct atmospheric inputs were less than 1% of those contributed by the Seine River and loadings of Pb and Zn represented 1.27% and 1.56% of the Seine contribution. Direct atmospheric inputs are negligible compared to fluvial inputs, but the indirect atmospheric deposition to the estuary was not estimated. Based on these results, trace metal concentrations in Paris have decreased by a factor of 4.6 for Zn and by a factor of 50 for Ni from 1988 to 2001. Of particular interest is the continued decrease in bulk deposition of Pb during this period, underlining the impact of policy initiatives concerning the reduction of lead on emissions in France.  相似文献   

8.
Development of heavy-metal deposition by precipitation in West Germany. 2. Arsenic, chromium, cobalt, and nickel Between 1984 and 1993 the deposition of As, Cr, Co and Ni with bulk precipitation was measured on 6 open field sites in Northrhine-Westphalia/Germany. The absolute amount of As, Cr, Co and Ni deposition varies according to field sites and annual precipitation. In all studied areas, however, As deposition with bulk precipitation decreased significantly during the observation period. Considering all research stations under study, the average As deposition fell from 11.0 g ha?1 in 1984 to 3.0 g ha?1 (r = ?0.982***). The reduction in As deposition corresponds with the reduction in As emission within the same period of time prognosticated. Immission of Cr and Co also decreased significantly over the majority of the studied areas. The avarage Cr immission fell from 8.5 g ha?1 in 1984 to 3.5 g ha?1 in 1993 (r = ?0.888***), whereas the average Co immission decreased from 2.6 g ha?1 to 1.1 g ha?1 (r = ?0.869***). In contrast, no reduction in Ni deposition with precipitation was found on any of the studied areas under observation. Co shows the lowest deposition rates. On average, 2.2 times as much Cd, 2.7 times as much As, 3.2 times as much Cr, 6.5 times as much Ni, and 66 times as much Pb was deposited on the six open field sites in Northrhine-Westphalia in 1993.  相似文献   

9.
The value of several biological monitors of the distribution of airborne Cr and Ni dust was studied in the vicinity of ferrochrome and stainless steel works. The following indigenous biomonitors were compared: the forest mosses Pleurozium schreberi and Hylocomium splendens, the epiphytic lichen Hypogymnia physodes, bark of Scots pine (Pinus silvestris), needle litter, earthworms (Dendrobaena octaedra) and moths (mainly Xylena vetusta). Results were compared and related to the heavy metal deposition estimated by the vertical snow sampling method. The representative sampling size at different pollution levels was investigated. In Cr it varied from 1 to 300 mg m?2 a?1. Of the biomonitors studied, the mosses showed most effective accumulation of heavy metals, their results having a clear relationship to the deposition and good replicability. The lichen gave almost as good results as the mosses. Both mosses and lichens collected heavy metals more effectively at low to moderate pollution loads than near the pollution source. The accumulation of heavy metals in bark was lower than in the mosses or lichen. The heavy metal content of earthworms indicated the degree of pollution well, but the replicability of the method was poor. The accumulation of heavy metals in moths was low.  相似文献   

10.

Purpose

This study aimed at investigating correlations between heavy metal concentrations in mosses and modelled deposition values as well as other site-specific and regional characteristics to determine which factors primarily affect cadmium, lead and mercury concentrations in mosses. The resulting relationships could potentially be used to enhance the spatial resolution of heavy metal deposition maps across Europe.

Materials and methods

Modelled heavy metal deposition data and data on the concentration of heavy metals in naturally growing mosses were integrated into a geographic information system and analysed by means of bivariate rank correlation analysis and multivariate decision trees. Modelled deposition data were validated annually with deposition measurements at up to 63 EMEP measurement stations within the European Monitoring and Evaluation Programme (EMEP), and mosses were collected at up to 7,000 sites at 5-year intervals between 1990 and 2005.

Results and discussion

Moderate to high correlations were found between cadmium and lead concentrations in mosses and modelled atmospheric deposition of these metals: Spearman rank correlation coefficients were between 0.62 and 0.67, and 0.67 and 0.73 for cadmium and lead, respectively (p?<?0.001). Multivariate decision tree analyses showed that cadmium and lead concentrations in mosses were primarily determined by the atmospheric deposition of these metals, followed by emissions of the metals. Low to very low correlations were observed between mercury concentrations in mosses and modelled atmospheric deposition of mercury. According to the multivariate analyses, spatial variations of the mercury concentration in mosses was primarily associated with the sampled moss species and not with the modelled deposition, but regional differences in the atmospheric chemistry of mercury and corresponding interactions with the moss may also be involved.

Conclusions

At least for cadmium and lead, concentrations in mosses are a valuable tool in determining and mapping the spatial variation in atmospheric deposition across Europe at a high spatial resolution. For mercury, more studies are needed to elucidate interactions of different chemical species with the moss.  相似文献   

11.
Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses   总被引：1，自引：0，他引：1  
The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for 137Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil and to the soil contaminated with the metals. The exposition to the contaminated soil resulted in the statistically significant increase of metal concentrations in the gametophytes.  相似文献   

12.
Impacts of heavy metal concentrations in sediments on the gastropod community structure were assessed in the coastal waters of Dumai, Sumatra, Indonesia. The objective of this study was to relate the levels of heavy metal pollution with the changes of gastropod community structure in the study area. Concentrations of Cd, Cu, Pb, Zn, Ni, and Fe in surface sediments collected from five sampling stations were analyzed and correlated with the abundance, species richness, and diversity of gastropod populations. Sediments at stations with more anthropogenic activities accumulated higher concentrations of heavy metals and consequently displayed lower abundances, lower species richness and diversity; while stations with lower heavy metal concentrations in sediments showed the opposite pattern in gastropod community metrics. The above findings are complemented by significant negative correlations p?<?0.05–0.01) between concentrations of Cd, Cu, Pb, Zn, and Ni in the sediments and gastropod abundance and species richness. Among the metals analyzed, Cu and Zn had strongest negative correlations with the gastropod diversity which suggests that these metals may be the most detrimental to gastropod populations in the mangrove area of Dumai coastal waters.  相似文献   

13.
Abstract

Thalli of the lichens Pseudevernia furfuracea, Usnea longissima, Lobaria pulmonaria, and Peltigera praetextata were taken from unpolluted areas and transplanted to a downtown site in Erzurum, Turkey. Heavy metals copper (Cu), chromium (Cr), zinc (Zn), lead (Pb), nickel (Ni), and iron (Fe) were measured after an 8 month exposure period. Changes in the heavy metal concentrations were observed during the exposure period in lichen species and in both locations. Heavy metal concentrations were significantly higher in Peltigera praetextata than the other species at the location nearest to the junction crossroads. Peltigera praetextata may be considered a good indicator. These results can be attributed to the effect of atmospheric pollutants on the transplanted lichens.  相似文献   

14.
As part of a survey of patterns of disease in relation to air pollution in various towns, atmospheric concentrations of metals were measured in Armadale, West Lothian. The first survey of metallic pollutants in the environment consisted of measuring selected metal concentrations in indigenous Hypnum cupressiforme throughout Armadale. As in other surveys using this moss, Hypnum proved to be most useful in collecting at least 9 metals from the atmosphere. Some values, such as Fe, were significantly lower in Armadale, than those levels found in a similar survey sited around a steelworks in Consett, England. However, other metals such as Cu were present in much higher concentrations. All metals measured (apart from Pb values, which showed the influence of traffic routes) revealed an increasing concentration from the periphery of the town towards the vicinity of Armadale's steel foundry.  相似文献   

15.
The influence of a change from daily to weekly sampling of bulk precipitation on the obtained deposition values was studied with parallel sampling for 8 months at the station of Virolahti in 2004. Due to dry deposition, the deposition values of the whole period were found to be 5–70% higher from weekly sampling than from daily sampling, the biggest difference being for K+, Ca2+, Mg+ and Na+. The collection efficiencies of the summer sampler and the winter sampler compared to the standard rain gauge were studied from daily sampling in 1991–2003 and weekly sampling in 2004–2008. The performance was best in summer and in winter with rain samples (median value 85–88%), while the median value for daily snow samples was 72%. In winter, the total sum of precipitation collected in the daily sampler and the weekly sampler was 78% and 69%, respectively. The deficit in the weekly sampler in winter was concluded to be due to evaporation, while from the summer sampler no evaporation seemed to occur. Use of the precipitation amount measured by the standard rain gauge when calculating annual precipitation-weighted mean values gave higher mean concentrations than the use of the precipitation measured by the deposition sampler itself, the biggest difference of 8–11% being in the sea-salt ions Cl?, Mg+ and Na+. It was concluded that the concentration and deposition values measured by daily and weekly bulk sampling are incompatible, and should not be combined into the same time series.  相似文献   

16.
Sulphur and heavy metal deposition in northern Finland (= in Lapland) and the Kola Peninsula were surveyed using Scots pine bark samples. Sulphur concentrations in bark close to the Kola smelters were on an average twice as high as on the Finnish side of the border. The Cu and Ni concentrations near the smelters were almost 100-fold the mean values in northern Finland. There was a marked decrease in the sulphur and heavy metal concentrations with increasing distance from the emission sources. The effects of emission from the Kola Peninsula were evident in Finland only close to the border, especially in the eastern parts of Inari (NE corner of Lapland) where the Cu and Ni concentrations were 2- to 6-fold those in western Lapland. The sulphur and heavy metal concentrations in most of northern Finland were low. However were the concentrations of Cr in bark in the SW corner of Lapland considerably high, due to the emissions from the Tornio refined steel plants.  相似文献   

17.
Two species of lichen native to southwest Lousiana, Parmotrema praesorediosum (Nyl.) Hale and Ramalina stenospora, Mull. Arg. have been investigated as air pollution monitors. Over the period 1983–88 samples were collected at 18 stations in the Lake Charles/Westlake/Sulphur area. The samples were analyzed for A1, Fe, Cu, Pb, Cd, Hg, Cr, and Zn. When metal concentrations in lichens were plotted vs year for certain representative stations, a dramatic reduction in the concentrations of certain metals was seen after 1983. When the most recent data are compared with those previously obtained, the effects of the industrial zone, which was previously demonstrated, have now all but disappeared.  相似文献   

18.
This study investigated the effect of anions on the uptake of heavy metals and aluminum by Brassica rapa L. from non-contaminated, Cd-contaminated, and sewage sludge compost (SSC)-amended sandy soil. Four types of artificial precipitation were applied: deionized water (pH 5.7) as a control, and solutions of HNO3, H2SO4, and HCl prepared to pH 4.5. Precipitation was applied daily during the last 20 d of cultivation. The pH of the Cd-treated soil after harvest was not affected by any precipitation treatment. Shoot concentrations of heavy metals and Al were unaffected by any treatments on non-contaminated soil. In contrast, all acid treatments increased the Cd concentration in shoots grown on Cd-contaminated soil, but only HNO3 precipitation increased it in SSC-amended soil. These results indicate, even without large soil pH change, there is a possibility that the Cd uptake by B. rapa L. depends on anions in precipitation and chemical form of Cd in the soil under conditions of heavy metal enrichment.  相似文献   

19.
The present study is an attempt to assess the heavy metal contamination in the marine environment of the Arabian Gulf of Saudi Arabia. The concentrations of heavy metals in water and the soft tissues of the bivalve species Meretrix meretrix Linnaeus, 1758, from different stations along the Arabian Gulf coastline, were determined during the summer season of 2008. Bioaccumulation of some heavy metals (Cd, Pb, Cu, and Zn) in fresh parts of the clam (M. meretrix) was measured by an atomic absorption spectrophotometer. The average concentrations of heavy metals in the clam tissues were 0.224?C0.908, 0.294?C2.496, 3.528?C8.196, and 12.864?C24.56 mg/kg wet weight for Cd, Pb, Cu, and Zn, respectively. In water, the mean concentration values of these metals were arranged in the following descending order: Pb > Cu > Zn > Cd. The heavy metal concentrations in tissues of M. meretrix were within the acceptable standards set by the US Environmental Protection Agency, the Commission Européenne, and the Food and Drug Administration of the USA. From the human public health point of view, these results seem to show no possibility of acute toxicities of Cd, Cu, Pb, and Zn if the edible clam is consumed. It is recommended that relevant authorities should carry out a continual assessment on the levels of these pollutants in the studied area.  相似文献   

20.

Alpine areas in north-western Italy are subject to high deposition of atmospheric pollutants. Chemical investigations on high-altitude lakes indicate that most of them are recovering from acidification; however, they are still affected by the deposition of pollutants from the atmosphere, especially of heavy metals. This study compares the concentrations of heavy metals in alpine lake waters with those found in atmospheric depositions, to identify the possible contribution of deposition inputs to surface water ecosystems. The results were analysed by multivariate statistical techniques to identify the main emission sources of the various metals. Levels of trace metals in alpine lakes are generally low, and bedrock and surficial geology proved to be a major factor controlling metal concentrations in lake water. In fact, terrigenous elements show a wide range of concentrations while metals of anthropogenic origin, such as lead and cadmium, are often below the detection limits of the method; chrome and nickel are also present in very low concentrations. The median values of heavy metals in Italian alpine lakes are similar to those found in other lake surveys performed in remote areas, especially as regards metals of anthropogenic origin. The Visual MINTEQ model was applied to long-term chemical data of selected alpine lakes, to calculate aluminium speciation and to simulate its change in response to gradual modifications in a unit of pH. The ultimate aim of the modelling was to evaluate the possible threat to aquatic organisms of these highly toxic compounds.

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