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841.
Comparison between the accumulation capacity of four lichen species transplanted to a urban site 总被引:1,自引:0,他引:1
Bergamaschi L Rizzio E Giaveri G Loppi S Gallorini M 《Environmental pollution (Barking, Essex : 1987)》2007,148(2):468-476
The capacity to accumulate trace elements from the atmosphere of the lichens Hypogymnia physodes, Parmelia sulcata, Pseudevernia furfuracea and Usnea gr. hirta transplanted to an urban site of N Italy was compared. Twenty-nine elements (Al, As, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hg, I, K, La, Mg, Mn, Ni, Pb, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Zn) were analyzed by Instrumental Neutron Activation Analysis (INAA) and Electro-Thermal Atomic Absorption Spectroscopy (ET-AAS). The ratio between the concentrations of each element in exposed samples to that of control samples (exposed-to-control ratio and EC ratio) was used to investigate the accumulation rates of lichen thalli. The results showed that in general elements did not exhibit well defined trends, but rather showed fluctuations, and indicated that H. physodes, P. furfuracea and U. gr. hirta have a similar accumulation capacity, while that of P. sulcata is lower. 相似文献
842.
Mayer T Bennie D Rosa F Rekas G Palabrica V Schachtschneider J 《Environmental pollution (Barking, Essex : 1987)》2007,147(3):683-690
Occurrence and fate of alkylphenols (APs), known endocrine disruptors, were investigated in a Great Lakes coastal wetland, Cootes Paradise, ON. The wetland, which receives discharges from a Wastewater Treatment Plant (WTP) and several Combined Sewer Overflows (CSOs), is an important spawning ground for fish and crucial habitat for other fauna. Elevated concentrations of nonylphenol ethoxylates (NPEs) and their degradation product nonylphenol (NP) were found in water and sediment samples near the sources. Since transfer of APs through the food chain is of concern, we compared their concentrations in invertebrates from clean and contaminated sites. The results reveal transfer of alkylphenolics from sediments to biota and their accumulation in the invertebrate tissue, particularly the highly hydrophobic 4-NP, whose concentrations ranged from 1.9 to 6.3 microg g(-1). To our knowledge, this is the first study to evaluate AP concentrations in tissue of benthic invertebrates under real environmental conditions. 相似文献
843.
Rao PS Ansari MF Gavane AG Pandit VI Nema P Devotta S 《Environmental monitoring and assessment》2007,128(1-3):323-328
Petroleum refineries are largest chemical industries that are responsible for the emission of several pollutants into the
atmosphere. Benzene is among the most important air pollutants that are emitted by petroleum refineries, since they are involved
in almost every refinery process. Volatile organic compounds (VOCs) are a major group of air pollutants, which play a critical
role in atmospheric chemistry. These contribute to toxic oxidants, which are harmful to ecosystem, human health and atmosphere.
The variability of pollutants is an important factor in determining human exposure to these chemicals. The ambient air concentrations
of benzene were measured in several sites around the Digboi petroleum refinery, near the city of Gowahati in northeast India,
during winter and summer 2004. The seasonal and spatial variations of the ambient air concentrations of this benzene were
investigated and analyzed. An estimation of the contribution of the refinery to the measured atmospheric levels of benzene
was also performed. The ambient air mixing ratios of benzene in a large area outside the refinery was generally low, in ppbv
range, much lower than the ambient air quality standards. This article presents the temporal and spatial variation of air
pollution in and around petroleum refinery and showed that no health risk due to benzene is present in the areas adjacent
to the refinery. 相似文献
844.
Validation of a European standard for the determination of hexavalent chromium in solid material 总被引:1,自引:0,他引:1
Tirez K Scharf H Calzolari D Cleven R Kisser M Lück D 《Journal of environmental monitoring : JEM》2007,9(7):749-759
A European standard for the determination of Cr(vi) in solid material has been elaborated in the framework of an international co-operation and finally validated in the course of an interlaboratory comparison. The procedure is based on the alkaline digestion prescribed by EPA method 3060A followed by ion chromatography and determines an operationally defined content of Cr(vi), including water-soluble and insoluble chromates. A preliminary robustness study was carried out in order to compare different extraction methodologies and to study the equivalency of different analytical methods for the determination of Cr(vi) in alkaline extracts of soil and waste materials. During an interlaboratory validation trial with 19 European laboratories a set of 4 samples (2 soil and 2 waste samples) was analysed to determine performance characteristics for different combinations of digestion and detection methods. With the procedures prescribed by the new European standard (EN 15192) acceptable results were obtained for both soil samples and one of the waste samples (sludge). However, for the second waste sample (fly ash) a large deviation in analytical results was observed. This indicates that particularly for waste materials a possible occurrence of strong matrix effects has to be considered and supplementary quality control data are needed in order to assess the validity of analytical results. The accuracy of the determination of Cr(vi) in solid matrices remains a challenging field in terms of maximum extraction efficiency and minimum species interconversion. 相似文献
845.
Martínez-Carballo E Sitka A González-Barreiro C Kreuzinger N Fürhacker M Scharf S Gans O 《Environmental pollution (Barking, Essex : 1987)》2007,145(2):489-496
A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl quaternary ammonium compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19ng/L for the enrichment of 500mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target compounds. 相似文献
846.
Hayes F Jones ML Mills G Ashmore M 《Environmental pollution (Barking, Essex : 1987)》2007,146(3):754-762
This study identified 83 species from existing publications suitable for inclusion in a database of sensitivity of species to ozone (OZOVEG database). An index, the relative sensitivity to ozone, was calculated for each species based on changes in biomass in order to test for species traits associated with ozone sensitivity. Meta-analysis of the ozone sensitivity data showed a wide inter-specific range in response to ozone. Some relationships in comparison to plant physiological and ecological characteristics were identified. Plants of the therophyte lifeform were particularly sensitive to ozone. Species with higher mature leaf N concentration were more sensitive to ozone than those with lower leaf N concentration. Some relationships between relative sensitivity to ozone and Ellenberg habitat requirements were also identified. In contrast, no relationships between relative sensitivity to ozone and mature leaf P concentration, Grime's CSR strategy, leaf longevity, flowering season, stomatal density and maximum altitude were found. The relative sensitivity of species and relationships with plant characteristics identified in this study could be used to predict sensitivity to ozone of untested species and communities. 相似文献
847.
Linking stress with macroscopic and microscopic leaf response in trees: new diagnostic perspectives 总被引:1,自引:0,他引:1
Günthardt-Goerg MS Vollenweider P 《Environmental pollution (Barking, Essex : 1987)》2007,147(3):467-488
Visible symptoms in tree foliage can be used for stress diagnosis once validated with microscopical analyses. This paper reviews and illustrates macroscopical and microscopical markers of stress with a biotic (bacteria, fungi, insects) or abiotic (frost, drought, mineral deficiency, heavy metal pollution in the soil, acidic deposition and ozone) origin helpful for the validation of symptoms in broadleaved and conifer trees. Differentiation of changes in the leaf or needle physiology, through ageing, senescence, accelerated cell senescence, programmed cell death and oxidative stress, provides additional clues raising diagnosis efficiency, especially in combination with information about the target of the stress agent at the tree, leaf/needle, tissue, cell and ultrastructural level. Given the increasing stress in a changing environment, this review discusses how integrated diagnostic approaches lead to better causal analysis to be applied for specific monitoring of stress factors affecting forest ecosystems. 相似文献
848.
Pilkington MG Caporn SJ Carroll JA Cresswell N Lee JA Emmett BA Bagchi R 《Environmental pollution (Barking, Essex : 1987)》2007,148(1):191-200
On an upland moor dominated by pioneer Calluna vulgaris and with an understorey of mosses and lichens, experimental plots were treated with factorial combinations of nitrogen (N) at +0 and +20kg Nha(-1)yr(-1), and phosphorus (P) at +0 and +5kg Pha(-1)yr(-1). Over the 4-year duration of the experiment, the cover of the Calluna canopy increased in density over time as part of normal phenological development. Moss cover increased initially in response to N addition but then remained static; increases in cover in response to P addition became stronger over time, eventually causing reductions in the cover of the dominant Calluna canopy. Lichen cover virtually disappeared within 4 years in plots receiving +20kg Nha(-1)yr(-1) and also in separate plots receiving +10kg Nha(-1)yr(-1), but this effect was reversed by the addition of P. 相似文献
849.
Characterization of gas/particle concentrations and partitioning of polychlorinated biphenyls (PCBs) measured in an urban site of Turkey 总被引:2,自引:0,他引:2
Air concentrations of polychlorinated biphenyls (PCBs) in both gas and particle phases were measured in an urban site (BUTAL-Merinos) of the city of Bursa, Turkey between August 2004 and May 2005. The mean of total (particle+gas) PCB concentrations was about 491.8+/-189.4pg/m(3). The main contributors for PCBs in the sampling site were the local sources and long-range atmospheric transport supported by back trajectory analysis. Lower molecular weight PCB congeners generally dominated in the samples. The particle phase of the measured PCBs accounted for 15% of the total PCB concentrations. Gas/particle distribution was investigated using different approaches such as log K(P)-log P(L)(o), log K(P)-log K(OA) and the Junge-Pankow model. Regression analysis among log K(P), log P(L)(o) and log K(OA) exhibited significant correlation at p<0.05. Correlation between PCB homologs and meteorological parameters was formed to investigate the possible relationships. 相似文献
850.
Dynamic responses of photosystem II in the Namib Desert shrub, Zygophyllum prismatocarpum, during and after foliar deposition of limestone dust 总被引:1,自引:0,他引:1
van Heerden PD Krüger GH Kilbourn Louw M 《Environmental pollution (Barking, Essex : 1987)》2007,146(1):34-45
The effects of limestone dust deposition on vegetation in desert ecosystems have not yet been reported. We investigated these effects in a succulent shrub from the Namib Desert at a limestone quarry near Skorpion Zinc mine (Namibia). Effects of limestone dust were determined in Zygophyllum prismatocarpum (dollar bush) plants with heavy, moderate and no visible foliar dust cover by means of chlorophyll a fluorescence measurements. Limestone dust deposition decreased overall plant performance through loss of chlorophyll content, inhibition of CO(2) assimilation, uncoupling of the oxygen-evolving complex and decreased electron transport. Importantly, dynamic recovery occurred after termination of limestone extraction at the quarry. Recovery was accelerated by rainfall, mainly because of dust removal from leaves and stimulation of new growth. These results indicate that limestone dust has severe effects on photosynthesis in desert shrubs, but that recovery is possible and that, in arid environments, this process is modulated by rainfall. 相似文献