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1.
Lake M?laren is the water supply and recreation area for more than 1 million people in central Sweden and subject to considerable environmental concern. To establish background data for assessments of contemporary levels of trophy and heavy metal pollution, sediment cores from the lake were analyzed. Diatom-inferred lake-water phosphorus concentrations suggest that pre-20th century nutrient levels in S?dra Bj?rkfj?rden, a basin in the eastern part of M?laren, were higher (c. 10-20 micrograms TP L-1) than previously assumed (c. 6 micrograms TP L-1). Stable lead isotope and lead concentration analyses from 3 basins (S. Bj?rkfj?rden, Gisselfj?rden and Ask?fj?rden) show that the lake was polluted in the 19th century and earlier from extensive metal production and processing in the catchment, particularly in the Bergslagen region. The lake has experienced a substantial improvement of the lead pollution situation in the 20th century following closure of the mining and metal industry. The lead pollution from the old mining industry was large compared to late-20th century pollution from car emissions, burning of fossil fuels and modern industries.  相似文献   

2.
Data from a large-scale foliar survey were used to calculate the extent to which N and S deposition determined the mineral composition of Scots pine and Norway spruce needles in Finland. Foliar data were available from 367 needle samples collected on 36 plots sampled almost annually between 1987 and 2000. A literature study of controlled experiments revealed that acidifying deposition mediates increasing N and S concentrations, and decreasing Mg:N and Ca:Al ratios in the needles. When this fingerprint for N and S elevated deposition on tree foliage was observed simultaneously with increased N and S inputs, it was considered sufficient evidence for assuming that acidifying deposition had altered the mineral composition of tree needles on that plot in the given year. Evidence for deposition-induced changes in the mineral composition of tree foliage was calculated on the basis of a simple frequency model. In the late eighties the evidence was found on 43% of the Norway spruce and 27% of Scots pine plots. The proportion of changed needle mineral composition decreased to below 8% for both species in the late nineties.  相似文献   

3.
In this study, the effect of mine work wastes on elemental composition (N, P, Ca, K, Mg, Fe, Mn, Cu, Zn) of some alpine and subalpine plant species and in soils were investigated in the surroundings of the Etibank Wolfram Mine Work in Uludag mountain. Soils and plant parts belonging to Thymus praecox Opiz., Acinos alpinus (L.) Moench, Plantago holosteum Scop and Festuca punctoria Sm species collected from three directions around Wolfram Mine Work were used for our investigations. All samples were analysed by flame atomic absorption spectrophotometer (FAAS) for Ca, K, Mg, Mn, Fe, Zn, and Cu. The significant differences among sample sites were in terms of pH, % CaCO3, % C, % N and % P contents of soil. The changes of Ca, Mg, Fe, Mn, Fe, Zn, and Cu contents in soil were determined to be due to mining activity. Of the four species examined, an important change was determined in concentrations of Mg, Mn, Fe and Zn although P. holosteum and F. punctoria were different in above- and below-ground parts, showing that plant element content is specific to species.  相似文献   

4.
Environmental Science and Pollution Research - Plastic pollution and the numerous consequences it has on aquatic life have become a huge concern in recent years. While many studies have been...  相似文献   

5.
Effects of heavy metals caused by urbanisation on soil nematode communities were investigated along an urban–suburban–rural gradient in southern Shenyang, China. The numbers of total nematodes increased significantly along the urban–rural gradient. Similar trends were observed in the values of Structure Index (SI), with lower values found in urban site and higher in the rural site. Generic richness and SI were sensitive indicators for assessing the effect of heavy metals on soil nematode communities. The Canonical Correspondence Analysis (CCA) indicated that copper concentration and Cation Exchange Capacity (CEC) were most important environmental parameters that influenced nematode distribution.  相似文献   

6.
In this paper the time evolution of heavy metal concentration of Pb, Zn, Cd and Hg, in the sediments of the Bay of Cádiz (southwest of Spain) is studied during the past century, as a result of the industrial influence in the zone. The study has been performed using sedimentary profiles that have been extracted from the seabed. The measurement of 210Pb and 137Cs radionuclides has provided the dating of the sediment layers, up to a depth corresponding to the age of 115 years. The relative sedimentation rates obtained are around 0.2 cm/year. The 137Cs activity profile reflects the concentration of this radionuclide in the atmosphere and into aquatic systems during the second half of the twentieth century. This profile has been used to ratify the results provided by the 210Pb dating method.  相似文献   

7.
Selected pharmaceuticals, among them analgesics, ss-blockers and anti-depressants as well as caffeine, the anti-bacterial triclosan and the insect repellent N,N-diethyl-3-toluamide (DEET) were determined in different sewage samples (sewage treatment plants, hospital effluents) from Troms?/Norway and in seawater from Troms?-Sound, into which the sewage is discharged. While caffeine, triclosan, ibuprofen and its major metabolites hydroxy- and carboxy-ibuprofen were present in all sewage samples, additional pharmaceuticals were observed in sewage containing hospital effluents. Concentrations were in the range of 20-293 microg/l (caffeine), 0.2-2.4 microg/l (triclosan) and 0.1-20 microg/l (sum ibuprofen + metabolites). In seawater, only caffeine (7-87 ng/l), DEET (0.4-13 ng/l) and ibuprofen + metabolites (sum concentration < LOQ-7.7 ng/l) were detected. Ibuprofen and its metabolites hydroxy- and carboxy-ibuprofen were quantified individually by use of the respective reference compounds. Relative amounts of the three compounds were determined in different types of water showing characteristic patterns, with hydroxy-ibuprofen being the major component in sewage whereas carboxy-ibuprofen was dominant in seawater samples. The patterns which were compared to those observed in similar samples from Germany indicated different transformation behaviour under limnic and marine conditions.  相似文献   

8.
Water quality was measured at eight stations on the Buyuk Menderes River in Turkey (Ad?güzel dam, Yenice regülator, Sarayköy bridge, Feslek regülator, Yenipazar bridge, Ayd?n bridge, Koçarl? bridge, Söke regülator) between 2000 and 2013 in February, April, June, August, October and December. The resulting data were evaluated in terms of biochemical oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO), ammoniac–nitrogen (NH3–N), nitrite–nitrogen (NO2–N), nitrate–nitrogen (NO3–N) and orthophosphate (o-PO4) aquaculture. According to the analysis, while river water pollution generally varied during each year, samples from certain measurement points demonstrated high pollution levels throughout the year. In this study, water parameters were classified according to the “Turkish water pollution control regulation.” The studied parameters are also compared with TS 266 and WHO guidelines. While levels at Sarayköy station were generally higher than other stations, values at Ad?güzel dam were the lowest, giving it the best water quality of the eight stations. The highest values on a yearly basis were obtained in 2007 due to the severe drought in the Menderes basin within which irrigation water levels fell to 4255 m3/ha. The BOD, COD levels are the lowest in 2009 and highest in 2007; the DO level is lowest in 2007 and highest in 2009; NH3–N, NO2–N, and NO3–N parameters are the lowest in 2007 and highest in 2009; and the o-PO4 are at the lowest level in 2004 and seen as the highest in 2007. Analysis of the data was performed by SPSS 21 statistics program. One direction ANOVA was applied to the data, which were also subject to Tukey multiple comparison tests. Differences between groups were evaluated at p?<?0.05. Box–plot graphs were used to demonstrate the data distribution. In the study, it was analyzed, the effect of fish species and pollution involved in the Büyük Menderes River so far on fish species.  相似文献   

9.
Environmental Science and Pollution Research - Heavy metals is a collective term describing metals and metalloids with a density higher than 5&nbsp;g/cm3. Some of them are essential...  相似文献   

10.
Laboratory-reared grey garden slugs, Deroceras reticulatum, were exposed to soil and food treated with solutions of three metal salts (CdCl2, ZnCl2, PbCl2) in three environmentally relevant concentrations, each for 21 days. Metal concentrations were determined in the soil, food and slugs by atomic absorption spectrophotometry (AAS). Zinc was localized ultrastructurally in the hepatopancreatic cells by means of energy-filtering transmission electron microscopy (EFTEM). Zinc, and also high amounts of copper, could be detected by electron spectroscopical imaging (ESI) and electron energy loss spectroscopy (EELS) in spherites of the basophilic cells. Ultrastructural responses to metal impact were investigated in two cell types of the hepatopancreas (digestive and basophilic cells) and the cellular responses were found to be dose- and metal-dependent. In order to evaluate the toxicity of the respective metal concentrations to the slugs, the ultrastructural reactions were semi-quantified and summarized as complex reaction patterns of numerous organelles. This novel approach provides a basis for the use of data from standardized tests as a background for risk assessment studies in the field.  相似文献   

11.
The impact of heavy metal levels (Cd, Cu, and Zn) on the reproductive parameters in natural populations of the Mediterranean killifish Aphanius fasciatus was monitored in four sites of the Tunisian coast. Our study covered a period of the reproductive cycle, from April to November 2009. The significantly higher levels of Cd, Cu, and Zn in the liver and gonads for both sexes (p?<?0.05) were observed in the most polluted site (Sfax coast). During the reproductive cycle of A. fasciatus, an unbalanced sex ratio in favor to females was observed for all the studied populations. The progression of the hepato- (HSI), gonadosomatic (GSI), and K-factor revealed a spatio-temporal variation between populations during the sampling period. Estradiol-17β amounts in the gonad tissues of females captured from the studied sites showed a significant difference, and the highest concentrations were noticed in the control site (Luza). Taking together, our data provide the first evidence of a physiologically stress and a disturbance of the reproductive status in natural populations of A. fasciatus.  相似文献   

12.
This study was designed to evaluate the impact of sewage sludge spreading on tropical soilborne heavy metal speciation. Sludgeborne heavy metal speciation was also assessed, and the potential mobility of the elements was classified as follows: Zn>Ni>Cu approximately Cr. Two sequential extraction procedures were applied to study Cr, Cu, Ni and Zn speciation in control soils and sludge-amended soils. We demonstrated that sewage sludge spreading over a 2-year period did not have an impact on soilborne heavy metal concentrations but affected speciation of the most mobile fractions of Ni and Zn. Both protocols were consistent for the organic matter fractions, with an increase in Cu, Zn and Cr concentrations in the amended soil as compared to the control soil. In addition, we highlighted that the two protocols characterized different pools of organic matter and that organic compounds remained in the solid matrix after extraction. With respect to the reducible fraction, completely opposite results were obtained with the two protocols and the solid residue study revealed that the two schemes were ineffective in characterizing iron and manganese fractions.  相似文献   

13.
This study characterizes over 5 years of high time resolution (5 min), airborne black carbon (BC) concentrations (July 2003 to December 2008) measured over Ahmedabad, an urban region in western India. The data were used to obtain different time averages of BC concentrations, and these averages were then used to assess the diurnal, seasonal, and annual variability of BC over the study region. Assessment of diurnal variations revealed a strong association between BC concentrations and vehicular traffic. Peaks in BC concentration were co-incident with the morning (0730 to 0830, LST) and late evening (1930 to 2030, LST) rush hour traffic. Additionally, diurnal variability in BC concentrations during major festivals (Diwali and Dushera during the months of October/November) revealed an increase in BC concentrations due to fireworks displays. Maximum half hourly BC concentrations during the festival days were as high as 79.8 μg m?3. However, the high concentrations rapidly decayed suggesting that local meteorology during the festive season was favorable for aerosol dispersion. A multiple linear regression (MLR) model with BC as the dependent variable and meteorological parameters as independent variables was fitted. The variability in temperature, humidity, wind speed, and wind direction accounted for about 49% of the variability in measured BC concentrations. Conditional probability function (CPF) analysis was used to identify the geographical location of local source regions contributing to the effective BC measured (at 880 nm) at the receptor site. The east north-east (ENE) direction to the receptor was identified as a major source region. National highway (NH8) and two coal-fired thermal power stations (at Gandhinagar and Sabarmati) were located in the identified direction, suggesting that local traffic and power plant emissions were likely contributors to the measured BC.  相似文献   

14.
Water samples were collected at monthly intervals during 1 year of monitoring from Kralk?z?, Dicle and Batman dam reservoirs in the Tigris River basin to assess the concentrations of dissolved heavy metals and to determine their spatial and seasonal variations. The results indicated that dissolved heavy metal concentrations in the reservoirs were very low, reflecting the natural background levels. The lowest total metal concentrations in the three dam reservoirs were detected at sampling sites close to the dam wall. However, the highest total concentrations were observed at sites, which are located at the entrance of the streams to the reservoirs. Fe, Cr and Ni were the most abundant elements in the reservoirs, whereas Cd and As were the less abundant. The mean concentrations of dissolved metals in the dam reservoirs never exceeded the maximum permitted concentrations established by EC (European Community), WHO and USEPA drinking water quality guidelines. All heavy metals showed significant seasonal variations. As, Cd, Cr, Cu, Fe, Ni and Pb displayed higher values in the dry season, while higher values for Zn in the wet season. Cluster analysis grouped all ten sampling sites into three clusters. Clusters 1 and 2, and cluster 3 corresponded to relatively low polluted and moderate polluted regions, respectively. PCA/FA demonstrated the dissolved metals in the dam reservoirs controlled by natural sources.  相似文献   

15.
Environmental Science and Pollution Research - Developing a novel, simple, and cost-effective analytical technique with high enrichment capacity and selectivity is crucial for environmental...  相似文献   

16.
We report the evaluation of changes in water quality, increasing pollution level, of a section of Suquía River basin (Córdoba, Argentina) by using Myriophyllum quitense as bioindicator in addition to the measurement of chemical parameters, combined with chemometrics (ANOVA, Cluster and Discriminant Analysis). Myriophyllum quitense was collected upstream from Córdoba city at an unpolluted site of Suquía River basin. After collection plants were transplanted to different sites with different pollution levels. Subsequent to transplantation plants were weekly collected from the original site as well as from transplantation stations. Water quality was evaluated throughout the transplantation experiment, while the use of this macrophyte as bioindicator was verified through the activation of its antioxidant defenses and biotransformation system. Myriophyllum quitense reacts to the pollution stress increasing the activity of glutathione-S-transferases (CDNB and Fluorodifen), glutathione reductase (GR) and peroxidase (POD). Elevated enzyme activities agreed to different pollution levels, especially inorganic nitrogen loads combined with elevated lead and aluminum concentrations, all of them originated by anthropogenic activities, thus presenting Myriophyllum quitense as a good biomonitor for assessment of water quality in this polluted aquatic ecosystem.  相似文献   

17.
Environmental Science and Pollution Research - This study investigated the human biomonitoring of heavy metals in the water, sediments, and tissues of mostly consumed fish species using Turkmen...  相似文献   

18.
Recent epidemiological and toxicological studies have shown associations between particulate matter and human health. However, the estimates of adverse health effects are inconsistent across many countries and areas. The stratification and interaction models were employed within the context of the generalized additive Poisson regression equation to examine the acute effects of fine particles on respiratory health and to explore the possible joint modification of temperature, humidity, and season in Beijing, China, for the period 2004–2009. The results revealed that the respiratory health damage threshold of the PM2.5 concentration was mainly within the range of 20–60 μg/m3, and the adverse effect of excessively high PM2.5 concentration maintained a stable level. In the most serious case, an increase of 10 μg/m3 PM2.5 results in an elevation of 4.60 % (95 % CI 3.84–4.60 %) and 4.48 % (95 % CI 3.53–5.41 %) with a lag of 3 days, values far higher than the average level of 0.69 % (95 % CI 0.54–0.85 %) and 1.32 % (95 % CI 1.02–1.61 %) for respiratory mortality and morbidity, respectively. There were strong seasonal patterns of adverse effects with the seasonal variation of temperature and humidity. The growth rates of respiratory mortality and morbidity were highest in winter. And, they increased 1.4 and 1.8 times in winter, greater than in the full year as PM2.5 increased 10 μg/m3.  相似文献   

19.
20.
The aim of the present study was to investigate whether exposure to high levels of persistent organic pollutants (POPs) affected a fish population in Lake Mjøsa. Lake Mjøsa is known to be contaminated by polybrominated diphenyl ethers (PBDEs), a subgroup of brominated flame retardants from local industrial activities. Fish from Lake Losna, a less contaminated lake located close to Lake Mjøsa, was used as reference (control).The sampling of burbot (Lota lota) was carried out between 2005 and 2008. Hepatic levels of POPs were analysed in burbot from the two lakes, and the fish were examined for bacterial- and parasite infection and histopathological changes. The levels of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), and PBDEs were about 10, 15 and 300 times higher in fish from Lake Mjøsa compared to fish from Lake Losna. Mycobacterium salmoniphilum was present in 7% and 35% of the fish from Lake Losna and Lake Mjøsa respectively. Significantly higher number of external and visceral macroscopic lesions, histopathological diffuse changes and granulomas were seen in fish from Lake Mjøsa compared to Lake Losna. Furthermore the parasite infection was higher and the hepatic lipid content was significantly lower in burbot from Lake Mjøsa. The results of the present study suggest that the high level of contamination in Lake Mjøsa could have a negative impact on the health status of wild fish inhabiting the lake.  相似文献   

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