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1.
Heavy metal deposition and changes in the deposition patterns were investigated on the basis of surveys carried out in 1985, 1990, 1995 and 2000. The concentrations of 10 elements (Cd, Cr, Cu, Fe, Ni, Pb, Zn and V; and As and Hg since 1995) were determined on moss (Hylocomium splendens, Pleurozium schreberi) samples collected from the same permanent sample plots in each survey. The heavy metal concentrations, apart from those in southernmost Finland and close to a number of major emission sources, were relatively low. The mean concentrations of all the heavy metals decreased during the period covered by the surveys. The metals that showed the strongest decrease in concentration since 1985 were Pb (78%), V (70%) and Cd (67%). The concentrations of the other heavy metals decreased by 16-34%. The concentrations of Cr, Cu and Ni were clearly associated with local emission point sources and changes in emission levels. The concentrations of As and Hg, which were measured for the first time during the 1995 survey, decreased on the average by 26% and 10%, respectively.  相似文献   

2.
The study of a Posidonia oceanica mat (a peat-like marine sediment) core has provided a record of changes in heavy metal abundances (Fe, Mn, Ni, Cr, Cu, Pb, Cd, Zn, As and Al) since the Mid-Holocene (last 4470 yr) in Portlligat Bay (NW Mediterranean). Metal contents were determined in P. oceanica. Both, the concentration records and the results of principal components analysis showed that metal pollution in the studied bay started ca. 2800 yr BP and steadily increased until present. The increase in Fe, Cu, Pb, Cd, Zn and As concentrations since ca. 2800 yr BP and in particular during Greek (ca. 2680-2465 cal BP) and Roman (ca. 2150-1740 cal BP) times shows an early anthropogenic pollution rise in the bay, which might be associated with large- and short-scale cultural and technological development. In the last ca. 1000 yr the concentrations of heavy metals, mainly derived from anthropogenic activities, have significantly increased (e.g. from ~ 15 to 47 μg g− 1 for Pb, ~ 23 to 95 μg g− 1 for Zn and ~ 8 to 228 μg g− 1 for As). Our study demonstrates for the first time the uniqueness of P. oceanica meadows as long-term archives of abundances, patterns, and trends of heavy metals during the Late Holocene in Mediterranean coastal ecosystems.  相似文献   

3.
To assess the feasibility of using animal excrement to biomonitor the extent of heavy metal contamination in the marine environment, concentrations of mercury (Hg), lead (Pb), copper (Cu) and zinc (Zn) in the fresh excrement of seabirds and marine mammals, along with other biomaterials, from the Arctic, Antarctica (West and East), and Xisha Archipelago of the South China Sea were determined. Results show that the excrement of marine animals at higher trophic levels generally contained high levels of Hg, demonstrating the biomagnification of Hg through food chains in different remote regions. Significant variations in metal accumulation in the excrements were observed among the distinctive geographical areas, with the highest Hg concentration in Xisha Archipelago and the highest Pb concentration in the Arctic, which reflects different levels of air metal pollution at various sampling locations. Concentrations of Cu in the excrements primarily correlate to the geochemical background levels in the regions. High Cu concentrations were found near the Great Wall Station in West Antarctica where a copper mineralized belt exists. No clear spatial variation pattern was found for Zn accumulation in the excrement. This study shows that animal excrement can be used as bioindicators for the level of metal contamination in the marine environment, with the advantages of easy sampling, accurate detection (i.e., with high levels of metal accumulation), and reconstructing historical metal contamination trends by long-term monitoring of sedimentary excrements.  相似文献   

4.
Ample evidence exists that exposure to high noise levels acts as a stressor, which over a long period may result in pathological side-effects. Studies also exist which indicate that the exposure of construction site workers to noise pollution is significantly greater than that of the public at large. Despite the enormous post-invasion growth in the construction of residential projects in the State of Kuwait, no study of construction noise pollution and workers' perceptions and awareness levels of this pervasive urban problem has been performed in Kuwait or in the Middle-East region. This research project has attempted to narrow this information gap. A systematic-randomly selected sample of 26 construction projects were monitored for noise pollution levels. More than 500 workers at the selected sites were also person-surveyed for their perceptions and awareness of construction noise. Although the measured noise levels were frequently and significantly above standard outdoor noise levels (especially the highest 10 percentile level, L 10) during most of the monitoring periods, a large percentage of the surveyed workers – particularly the labourers and those with low education – did not perceive noise as a problem, and were not aware of its impacts. During the 10-month noise measurement period, no one was seen to be equipped with a hearing protection device. A number of recommendations end the article.  相似文献   

5.
This paper reports a study of pollution in the coastal waters of Jijel, Algeria, using algae Ulva lactuca and Corallina officinalis as bioindicators. Samples of seawater and algae were collected at four different stations from the coast of Jijel, during the period of April–June 2014. The heavy metal content (Pb and Zn) was determined in seawater and in the algae tissue by the technique of atomic absorption spectrophotometry. In seawater, the contents of heavy metals vary from 0.017 to 0.03 mg/l (Pb) and 0.235 to 0.873 mg/l. In the algae tissues, metals concentrations vary between 1.88 to 6.25 μg g?1 dry weight (Pb), and from 92 to 178.9 μg g?1 dry weight (Zn). These levels differ by site and species. The calculation of the bioconcentration factor (BCF) leads us to conclude that algae bioaccumulate significant levels of Pb and Zn metals in their tissues. Our results shows that the species of C. officinalis bioaccumulate the metals Pb and Zn more than U. lactuca, where, high biosorption of Zn was observed with BCF values between 203.21 and 238.40. Zn content in seawater and algae tissues appear higher than standards set by USEPA and guides values of Certified Reference Materials, but Pb levels appear lower than this standard.  相似文献   

6.
Numerical taxonomy has been applied to explain the behaviour of macroconstituents (Na, K, Ca, Mg) and heavy metals (Cr, Mn, Fe, Co, Ni, Pb, Cu, Zn, Cd) in different ecological sections (mollucs, plants, rain, drv deposition, soils, airborne dust, lixiviates through soils, springs) in the industrialized area near Bilbao (Spain). Distances based on correlation coefficients and mean Euclidean distances have been used for drawing dendrograms of metals and sections. Three types of effects may be distinguished, due to potassium, other macrocomponents (Na, Ca, Mg) and heavy metals as a result of the accumulation of these constituents in specific sections of the environment.  相似文献   

7.
In this study the Pb concentration in honeybees was determined by graphite furnace AAS after peroral administration of PbCl2. The Pb concentration, expressed on a dry weight base was determined in relation to the distribution over the body, the accumulation time, the clearance and the exposure dose. Pb is concentrated in the digestive system with the midgut accounting for 67% and the rectum for 27% of the accumulated metal. The barrier function of this system is thus corroborated in honeybees. Pb accumulation happens slowly in young bees which feed mainly on pollen; once they switch from pollen to nectar there is a sharp rise in their Pb content. After the 26th day a limit of tissue accumulation seems to be reached. Pb accumulation is equally efficient when the contamination starts at a forager age. Pb clearance is slower than expected; after 12 days only one third of the initial lead burden has been cleared. The Pb concentration in the animals increases significantly with the Pb concentration in the sugar syrup which they are fed, except at the highest dose of 50 mg/l. The possible use of honeybees as biomonitors for Pb pollution seems promising from these results.  相似文献   

8.
The bioaccumulation and retention capacities of some key local contaminants of the New Caledonia lagoon (Ag, As, Cd, Co, Cr, Cu, Mn, Ni and Zn) have been determined in the oyster Isognomon isognomon and the edible clam Gafrarium tumidum during transplantation experiments. In a first set of experiments, oysters and clams from a clean site were transplanted into contaminated sites. Uptake kinetics determined in the field indicated that for Cr and Cu in oysters and Co, Ni, and Zn in clams, concentrations in transplanted bivalves reached those of resident organisms after 100d, whereas for the other elements, it would require a longer time for transplanted bivalves to reach the same levels as in the resident populations (e.g., up to 3 years for Cd). However, the slow uptake rate for metals observed in the latter transplantation is rather related to low bioavailability of metals at the contaminated sites than to low bioaccumulation efficiency of the organisms. Indeed, results of a second transplantation experiment into two highly contaminated stations indicated a faster bioaccumulation of metals in both bivalves. Results of both transplantations point out that the clam G. tumidum is a more effective bioindicator of mining contamination than I. isognomon, since it is able to bioaccumulate the contaminants to a greater extent. However the very efficient metal retention capacity noted for most elements indicates that organisms originating from contaminated sites would not be suitable for monitoring areas of lower contamination. Hence, geographical origin of animals to be transplanted in a monitoring perspective should be carefully selected.  相似文献   

9.
The suitability of using helminth communities as bioindicators of environmental quality of the Yucatan coastal lagoons status was tested on the checkered puffer (Spheroides testudineus) in four coastal lagoons along the Yucatan coast. The concentration of chemical pollutants in sediments, water quality parameters, helminth infracommunity characteristics, as well as fish physiological biomarkers, including EROD (7-ethoxyresorufin-O-deethylase) and catalase activities, were measured. Results from sediment analyses demonstrated the presence of hydrocarbons, organochlorine pesticides and polychlorinated biphenyls at varying concentrations, some of which exceeded the Probability Effect Level (PEL). Significant negative associations among organochlorine pesticides, infracommunity characteristics and fish physiological responses were observed in most of the lagoons. Results suggest that EROD activity and parasite infracommunity characteristics could be useful tools to evaluate the effects of chemical pollutants on the fish host and in the environment. Importantly, certain parasites appear to influence biomarker measurements, indicating that parasites should be considered in ecotoxicological studies.  相似文献   

10.
11.
This paper presents, the concentrations of total Hg, Cd and Zn in edible muscle tissue, and in the liver of the fish Micropogonias furnieri and Mugil liza from the Samborombon Bay, La Plata river estuary, Argentina. The highest accumulation of the three metals was observed in liver samples, whereas in muscle tissue concentrations they were always lower, values even lower than the detection limit of the analytical method used. A marked relationship between metal contents of the studied species and their trophic and ecological habits was observed. In all cases, metal levels found in edible muscle tissue were lower than the international standards of reference for organisms directed to human consumption. Finally, the validity of using these two species as bioindicators of heavy metal pollution in the assessed ecosystem was discussed.  相似文献   

12.
Levels of eleven trace metals (Ag, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg) and four macronutrients (Na, K, Ca and Mg) were estimated in the edible muscle of six commercially exploited fish species using the atomic absorption spectrophotometric method. The fish included in the study were: Argyrops spinifer, Fistularia petimba, Bramnoplaties suppositus, Lepidotriqla omaneaisis, Pampus argentus and Sphyraena obtusata harvested from the south‐west coast of the Arabian Sea along the Karachi coast, Pakistan. All metals have shown substantial increase in their average levels over the past few years. Pampus argentus was found undesirable for human consumption as it contained elevated levels of five metals (As, Cr, Pb, Zn and Hg). This species could be used to monitor marine trace metal pollution since it was found to contain consistently enhanced levels of the industrial metals.  相似文献   

13.
Inductively coupled plasma atomic emission spectrophotometry (ICP-AES) was used to determine heavy metal concentrations in the shells and soft tissues of the periwinkle Littorina littorea, collected at seven sites along the Scheldt estuary. Several metals accumulate in the animals soft body parts, and are related to the seawards decreasing pollution gradient. No clear correlation with a previously detected shell size patterning could be established.  相似文献   

14.
Manganese, Zn, Pb, Cu, Cr and Cd concentrations in snow collected in and around urban areas and from snow dumping stations in Hokkaido were determined by Zeeman-type atomic absorption spectrophotometry. We compared the heavy metal concentrations in the snow with background levels to see whether they could be used as an effective indicator of urban air pollution. The heavy metal concentrations in the snow clearly increased towards the center of the city of Sapporo; they were influenced by local pollution in the industrial area of the city and by the effect of the seasonal wind from the northwest. In the cities, we found the greatest influence on heavy metal concentrations was air pollution caused by industrial activities. The elemental concentrations in urban snow were from several to tens of times higher than background levels. The mean concentrations of the elements studied were in the order Mn greater than Zn greater than Pb greater than Cu greater than Cr greater than Cd, the same as in water except for Pb. We propose that data on trace metal concentrations in snow are a reliable guide to the degree of air pollution, and can be used as a simple and effective indicator of urban air pollution.  相似文献   

15.
This study reports on the concentration of both, toxic (Hg) and essential (Fe, Cu, Zn) metals in representative species, at four hydrothermal vents along the Mid-Atlantic Ridge (MAR) corresponding to the different exposure conditions that are the result of contrasted geological setting and different depths along the ridge axis. Macro fauna collected from these vent sites showed markedly different whole tissue concentration of metals reflecting exposure levels. Bio-transfer of metals within a typical hydrothermal food chain was investigated. There were trophic level-specific variations in essential metal accumulation showing a general trend within which the secondary consumers (predators/scavengers) and primary consumers (filter-feeder/symbiont reliant species like the mixotrophic mollusks and sponges all having metal concentrations above those in passive suspension-feeders such as echinoderms, gorgonians) accumulated highest concentrations of all elements followed by primary producers such as endosymbiont bacteria. Mercury accumulation followed a somewhat different sequence among the same taxonomic groups: top concentrations in the symbiont-bearing filter-feeder bivalves >crustaceans> sponges > bacteria > echinoderms, gorgonians and tunicates. There were no indications of biomagnification of Hg, Cu and Zn unlike Fe that showed positive transference factors (TF) along two trophic levels of a typical chain at Menez Gwen.  相似文献   

16.
Whole soft tissue concentrations of Mn, Co, Ni, Cu, Zn, Pb, Cd and U were measured in two species of freshwater (unionid) bivalves (Hyridella depressa and Velesunio ambiguus) from a minimally polluted site in the Hawkesbury-Nepean River, south-eastern Australia. Although the mean concentrations of metals in the tissue were similar for each bivalve species, their patterns of accumulation were dissimilar. For each metal, positive linear relationships between tissue concentration and shell length (r2 = 0.37-0.77; P < or = 0.001) and tissue dry weight (r2 = 0.29-0.51; P < or = 0.01) were found in H. depressa, but not in V. ambiguus. However, for both species, positive linear relationships were found between the tissue concentration of each divalent metal and Ca tissue concentration (r2 = 0.59-0.97; P < or = 0.001). For both bivalve species, the normalised rates of accumulation of the metals relative to increasing Ca concentration and/or size, were U approximately = Cd > or = Pb > or = Mn > Co > or = Zn > Cu > Ni. The differential rates of accumulation of divalent metals are interpreted as being predominantly governed by their varying loss rates, which are controlled by the differing solubilities (log Ksp values) of the metals in the phosphatic extracellular granules, the demonstrated major sites of metal deposition in the tissue of H. depressa and V. ambiguus. The rates of accumulation of Mn, Co, Zn, Cu and Ni were linearly and inversely related (r2 = 0.91-0.97; P < or = 0.001) to their solubilities as hydrogen phosphates, a finding consistent with the bioaccumulation model previously developed for the alkaline-earth metals. However, for U, Cd and Pb, this linear inverse relationship did not continue to hold, i.e. their rates of accumulation did not increase with decreasing solubility. However, these results are still consistent with the model if U, Cd and Pb are so insoluble in the granules of H. depressa and V. ambiguus over their lifetime (up to approx. 50 years) that there is effectively no loss of these metals, and hence, no differential between their rates of accumulation. The present results reaffirm the use of Ca tissue concentration to predict the tissue concentrations of other divalent metals by explaining up to 94 and 97% of the variability between individual bivalves of H. depressa and V. ambiguus, respectively. The use of Ca tissue concentration to effectively minimise the inherent variability between individuals in their metal tissue improves the ability of an investigator to discern smaller spatial and/or temporal differences in the metal tissue concentrations of these bivalves, and thus to detect metal pollution.  相似文献   

17.
Factors influencing the impact of highway lead on the quality of water resources are discussed, and the available information on each factor critically evaluated. Hence, the sources of lead input to the highway environment are described and the subsequent airborne and waterborne dispersal to the receiving waters discussed in detail. It appears that the impact on surface waters is confined to the lead contained in surface runoff, as the lead dispersed to roadside soils is effectively immobilized in the top 10 cm of soil. The concentration of lead in highway runoff can reach levels far in excess of those normally encountered in surface waters. However, when evaluating the impact on the receiving waters, the importance of considering both the lead mass discharge from the highway and the subsequent dilution by the receiving water is stressed. Finally, the present inadequate understanding of the physiochemical forms of lead in polluted and natural waters is highlighted.  相似文献   

18.
Aquatic plants have been used as hydrological tracers in groundwater fed river systems. In nature, patterns in plant distribution have been attributed to ammonium (NH4) toxicity and phosphate (PO4) limitation, while some laboratory studies have focused on the role of the partial pressure of CO2 (pCO2). The aims of this study were (i) to test whether plant distribution was more related to pCO2 than NH4 and PO4 in nature, (ii) to develop and test the predictive power of new plant indices for pCO2, NH4 and PO4, and (iii) to test the potential causality of the relationships using species eco-physiological traits. These tests were carried out with field data from the Rhine, Rhône and Danube river basins. Species composition was best related to the effect of pCO2. The pCO2 plant index was well calibrated (r= 0.73) and had the best predictive power (r= 0.47) of the three indices tested on independent datasets. The plant-pCO2 relationship was supported by a biological mechanism: the ability of strictly submerged species of aquatic vascular plants to use HCO3 under low pCO2. This was not the whole story: the effects of pCO2, NH4 and PO4 on plant distribution were partially confounded and interacted all together with temperature. However, neither NH4 toxicity nor P limitation could be asserted using species eco-physiological traits. Moreover, the predictive power of the NH4 and PO4 plant indices was not as strong as pCO2, at r= 0.24 and r= 0.27, respectively. Other potentially confounding variables such as spatial structure, biotic and physical factors were unlikely to confound the findings of this study.  相似文献   

19.
Concentrations of Al, Fe, Mn, Cu, Zn, V, Ni, Co, Cr, Cd and Pb in the Asian periwinkle Littorina brevicula were determined from 39 sampling locations along the whole Korean coast. Metal concentrations in the periwinkle varied highly with sampling stations, but the variations could be well explained by the body size after eliminating the data exceeding the 'High' criteria. Among the stations exceeding the 'High' criteria corresponding to mean plus one standard deviation of the logarithms of the individual site mean, some stations exhibited values higher than expected from the relationship between metal body burden and body size, indicating that these locations were polluted with metals. However, several 'High' stations followed the trends of the curve, suggesting that they resulted from the effect of their small body size, not from environmental contamination. Periwinkles of similar body sizes exhibited same range of metal concentrations in their body, independent of geographical position.  相似文献   

20.
This study was specifically aimed to determine the levels of beryllium in environmental samples near the vicinity of the beryllium metal plant (BMP). Air particulate samples collected at the BMP site, in the non-monsoon and monsoon seasons, showed an average beryllium concentration of 0.3 and 0.1 ng m(-3) respectively, where as rain water samples showed the beryllium values in the range of 0.01-0.2 ng ml(-1). The suspended particulate matter (dust load) at the site studied was 570 and 250 microg m(-3) in the non-monsoon and monsoon seasons respectively. The results obtained show that, in the environment, 80% of the total beryllium present is removed by rain.  相似文献   

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