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91.
Brázová T Hanzelová V Miklisová D Salgovičová D Turčeková L 《Environmental monitoring and assessment》2012,184(11):6553-6561
The distribution and concentrations of polychlorinated biphenyls (PCBs) were determined in fish species (European perch Perca fluviatilis, northern pike Esox lucius, pike perch Sander lucioperca, wels catfish Silirus glanus, common carp Cyprinus carpio, European eel Anguilla anguilla, freshwater bream Abramis brama, goldfish Carassius auratus, and roach Rutilus rutilus) in a heavily polluted water reservoir Zemplínska ?írava (Slovakia). The study performed at two different time points 5?years apart (2004 and 2009) revealed serious PCB contamination of fish muscle tissue and significant interspecies as well as tissue-specific differences in PCB uptake by fish. Total PCBs broadly correlated with the trophic position of individual fish species within a food chain (P?0.01). The concentrations were particularly high in predatory fish species, perch, pike, and pike perch (108.0, 90.1, and 113.0?mg?kg(-1) lipid wt, respectively), but comparable PCB values were also found in non-predatory detrivorous freshwater bream (128.0?mg?kg(-1) lipid wt). The lowest PCB values were surprisingly assessed in European eel (17.1?mg?kg(-1) lipid wt). Tissue analysis showed the highest storage capacity of the liver (hepatopancreas in cyprinids) with maximum concentrations recorded found in northern pike (214.0?mg?kg(-1) lipid wt) and freshwater bream (163.0?mg?kg(-1) lipid wt). Negative correlations, mostly not significant, between the total PCB concentrations and fish weight were observed (P?>?0.05). The study has shown that the kind of fish, its feeding habit, and specific conditions of the habitat are mutually interrelated factors that are responsible for significant variations in fish body burdens. A tendency to PCB biomagnification was also proved in some fish species of this water reservoir. 相似文献
92.
Multivariate analysis of mixed contaminants (PAHs and heavy metals) at manufactured gas plant site soils 总被引:1,自引:0,他引:1
Principal component analysis (PCA) was used to provide an overview of the distribution pattern of polycyclic aromatic hydrocarbons
(PAHs) and heavy metals in former manufactured gas plant (MGP) site soils. PCA is the powerful multivariate method to identify
the patterns in data and expressing their similarities and differences. Ten PAHs (naphthalene, acenapthylene, acenaphthene,
fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo[a]pyrene) and four toxic heavy metals — lead (Pb), cadmium (Cd), chromium (Cr) and zinc (Zn) — were detected in the site soils.
PAH contamination was contributed equally by both low and high molecular weight PAHs. PCA was performed using the varimax
rotation method in SPSS, 17.0. Two principal components accounting for 91.7% of the total variance was retained using scree
test. Principle component 1 (PC1) substantially explained the dominance of PAH contamination in the MGP site soils. All PAHs,
except anthracene, were positively correlated in PC1. There was a common thread in high molecular weight PAHs loadings, where
the loadings were inversely proportional to the hydrophobicity and molecular weight of individual PAHs. Anthracene, which
was less correlated with other individual PAHs, deviated well from the origin which can be ascribed to its lower toxicity
and different origin than its isomer phenanthrene. Among the four major heavy metals studied in MGP sites, Pb, Cd and Cr were
negatively correlated in PC1 but showed strong positive correlation in principle component 2 (PC2). Although metals may not
have originated directly from gaswork processes, the correlation between PAHs and metals suggests that the materials used
in these sites may have contributed to high concentrations of Pb, Cd, Cr and Zn. Thus, multivariate analysis helped to identify
the sources of PAHs, heavy metals and their association in MGP site, and thereby better characterise the site risk, which
would not be possible if one uses chemical analysis alone. 相似文献
93.
Highways and main roads are a potential source of contamination for the surrounding environment. High traffic rates result in elevated heavy metal concentrations in road runoff, soil and water seepage, which has attracted much attention in the recent past. Nonetheless, investigations of pollutants in roadside soils are still a subject of major interest due to the rapid development of traffic systems and increasing traffic all over the world. The accumulation of the heavy metals Pb, Cd, Cu and Zn in soils along the oldest federal highway of the world has been studied by sampling a roadside transect of 125 by 10?m. In addition, heavy metal concentrations of Pb, Cd, Zn, Cu, Ni and Cr in soil solutions from different distances (2.5, 5 and 10?m) from the hard shoulder of the highway and from three soil depths (10, 30, and 50?cm) were investigated. The results show that heavy metal concentrations are up to 20 times increased compared to the geochemical background levels and a reference site of 800-m distance from the roadside. Soil matrix concentrations in the topsoil (0-10?cm) mostly exceeded the precautionary values of the German Federal Soil Protection and Contamination Ordinance (BBodSchV). The concentrations of Cd, Pb and Zn in the soil matrix tended to decrease with distance from the roadside edge, whereas the concentrations in the soil solution increased at a distance of 10?m onwards due to a lower soil pH. Because of both high pH values and a high sorption capacity of the soils, soil solution concentrations seldom exceeded the trigger values of the German Federal Soil Protection and Contamination Ordinance (BBodSchV) for transferring soil solution to groundwater. 相似文献
94.
95.
The concentrations of heavy metals and metals (Zn, Pb, Bi, Cd, Ni, Co, Fe, Mn, Mg, Cu, Cr, Ca, Sr, Na, Li, K) were measured in muscle of five species Cyprinus carpio (from I??kl? dam), Scardinius erythrophthalmus (from I??kl? dam), Tinca tinca (from I??kl? dam), C. carpio (from Karaca?ren dam), Carassius carassius (from Karaca?ren dam) caught from I??kl? and Karaca?ren. The highest metal was Na (466.95 μg/g) in C. carassius, while the lowest levels were Fe (0.37 μg/g) and Cu (0.37 μg/g) in C. carpio from I??kl? dam. The mean concentrations μg/g d.w. some of heavy metals in muscle of C. carpio (from I??kl? dam), S. erythrophthalmus (from I??kl? dam), T. tinca (from I??kl? dam), C. carpio (from Karaca?ren dam), C. carassius (from Karaca?ren dam) were as follows: Cd 2.00-2.10-1.95-2.06-2.27, Zn 4.36-2.64-13.13-13.33-24.47, Pb 1.65-1.24-1.90-2.37-2.41, Co 2.46-2.37-2.48-2.58-2.80, Mg 138.51-154.35-218.59-204.58-202.16, Fe 0.37-2.62-3.17-3.01-12.33, respectively. 相似文献
96.
Jürgens N Schmiedel U Haarmeyer DH Dengler J Finckh M Goetze D Gröngröft A Hahn K Koulibaly A Luther-Mosebach J Muche G Oldeland J Petersen A Porembski S Rutherford MC Schmidt M Sinsin B Strohbach BJ Thiombiano A Wittig R Zizka G 《Environmental monitoring and assessment》2012,184(2):655-678
The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1?km2 and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects. 相似文献
97.
Giuseppa Di Bella Vincenzo Lo Turco Angela Giorgia Potortì Rossana Rando Patrizia Licata Giacomo Dugo 《Environmental monitoring and assessment》2013,185(9):7517-7525
Our study was carried out on two species of clams, Venerupis aurea laeta and Cerastoderma edule glaucum, from Ganzirri Lake considered as “environmental biomarkers” for their changes in physiology, morphology or distribution under the influence of substances in the environment. The aim of the present study was to conduct a statistical analysis on Venerupis and Cerastoderma to investigate the difference between the two autochthonous clams according to the presence of metals, and to link metal concentrations to the reproductive cycle of clam during 2009–2010. Metal analysis was carried out with inductively coupled plasma mass spectrometry (ICP-MS). Accuracy and precision were assessed by analyzing the certified standard matrix: mussel tissue NIST SRM 2976. The multivariate analysis was made using the SPSS 13.0 software package for Windows (SPSS Inc., Chicago, IL). In this study, the concentrations of some metals found in clam tissues showed seasonal cycles with higher values in summer than in winter. The significances of metal concentrations differences between Venerupis and Cerastoderma samples were estimated with Mann–Whitney U-test. The concentrations of Ag, As, Cd, Mn, Se and Zn show a significant p-level that suggests a difference between the two group samples. Statistical analysis showed that the link of metal concentrations to the reproductive cycles of Venerupis and Cerastoderma was not evident. 相似文献
98.
A study of chemical and sedimentological parameters integrated with benthic foraminifera investigation was conducted along
the northern coast of Gabes Gulf. Thirty-two samples were studied and a total of 68 benthic foraminiferal species were identified.
Heavy metals enrichment factors and total hydrocarbon concentrations showed both metal and petrogenic pollution related mainly
to phosphogypsum, sewage, and fishing activities. Statistical analysis (bivariate correlation and hierarchical cluster analysis)
show a possible control of these pollutants on density, diversity, as well as the taxonomic composition of the benthic foraminiferal
assemblages. The extent to which the population was found less dense and less diversified corresponded to the degree to which
the sediment was contaminated. In these contaminated sites, an increase in relative abundance of opportunistic species such
Ammonia tepida and Haynesina germanica was found. Far from pollution, foraminiferal assemblages are dominated by species characteristic of Mediterranean shallow
water (Ammonia beccarii, Ammonia parkinsoniana, Elphidium crispum, Elphidium williamsoni, Elphidium advenum, Peneroplis planatus, Peneroplis pertesus). 相似文献
99.
Assessment of Spatiotemporal Varying Relationships Between Rainfall,Land Cover and Surface Water Area Using Geographically Weighted Regression 总被引:6,自引:0,他引:6
Stuart?BrownEmail author Vincent?L.?Versace Laurie?Laurenson Daniel?Ierodiaconou Jonathon?Fawcett Scott?Salzman 《Environmental Modeling and Assessment》2012,17(3):241-254
Traditional regression techniques such as ordinary least squares (OLS) are often unable to accurately model spatially varying
data and may ignore or hide local variations in model coefficients. A relatively new technique, geographically weighted regression
(GWR) has been shown to greatly improve model performance compared to OLS in terms of higher R
2 and lower corrected Akaike information criterion (AICC). GWR models have the potential to improve reliabilities of the identified relationships by reducing spatial autocorrelations
and by accounting for local variations and spatial non-stationarity between dependent and independent variables. In this study,
GWR was used to examine the relationship between land cover, rainfall and surface water habitat in 149 sub-catchments in a
predominately agricultural region covering 2.6 million ha in southeast Australia. The application of the GWR models revealed
that the relationships between land cover, rainfall and surface water habitat display significant spatial non-stationarity.
GWR showed improvements over analogous OLS models in terms of higher R
2 and lower AICC. The increased explanatory power of GWR was confirmed by the results of an approximate likelihood ratio test, which showed
statistically significant improvements over analogous OLS models. The models suggest that the amount of surface water area
in the landscape is related to anthropogenic drainage practices enhancing runoff to facilitate intensive agriculture and increased
plantation forestry. However, with some key variables not present in our analysis, the strength of this relationship could
not be qualified. GWR techniques have the potential to serve as a useful tool for environmental research and management across
a broad range of scales for the investigation of spatially varying relationships. 相似文献
100.
Mehmet Sinan Bilgili Gamze Varank Elif Sekman Selin Top Didem Özçimen Remziye Yazıcı 《Environmental Modeling and Assessment》2012,17(3):289-300
Since phenols and phenolic compounds in many industrial wastewaters are toxic organic contaminants for humans and aquatic
life, to remove these compounds via the most efficient way is very important for environmental remediation treatment. In this
context, almost all of the isotherm models (Freundlich, Langmuir, Temkin, Redlich–Peterson, Sips, and Khan) for adsorption
in the literature were applied to explain the adsorption mechanism of 4-chlorophenol on activated carbon in this study. Also
theoretical modeling data were obtained using model equations; interpolation and analysis of variance were made to compare
data by using statistics software. In addition, the thermodynamic and kinetic studies for adsorption mechanism were included
in the article. The adsorption of 4-chlorophenol on activated carbon fits well to the pseudo-first-order kinetic model than
the pseudo-second-order, intraparticular diffusion and Bangham models. It is also indicated that 4-chlorophenol adsorption
by granular activated carbon would be attributed to a type of transition between physical and chemical adsorption rather than
a pure physical or chemical adsorption process. As a result, an environmental remediation problem and the adsorption mechanism
on activated carbon that can be regarded as a solution to this problem are described and explained using the mathematical
models and calculations in this study. 相似文献