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391.
Arsenic distribution in water/sediment system of Sevojno   总被引:1,自引:0,他引:1  
Arsenic is a toxic and carcinogenic element. Its toxicity depends on its oxidation state and its concentration. The aim of this paper is to determine, for the first time, the concentration levels of arsenic in water and sediment during the spring/summer period of 2009 in Sevojno, a region in West Serbia with a long industrial tradition, as well as to determine the model of arsenic distribution in water/sediment system and the level of its compatibility with the existing theoretical model. Adsorption is a continual process in the environment. It plays a very important role in the transport and fate of pollutants, especially in sediment. The adsorption of arsenic was examined using the Freundlich adsorption isotherm.  相似文献   
392.
Considering growing population and decreasing mineral resource reserves, the issue of undermining has been and shall remain very topical. This study aims to identify the mutual connections between mined out panels of a deposit and the final manifestations on the ground surface related to deep black coal mining. On the grounds of the identified connections, the study describes a method to simplify a common evaluation of undermined areas according to building site categories. Within the study, a demarcation of the areas was conducted in two localities in Czech Republic influenced by the effects of undermining in the Upper-Silesian Basin. In the allotment of the CSM Mine, an area unsuitable for founding structures was defined from the centre of the worked out workings to the distance of 175 m from the panel's edge, for which the corresponding break angle is 78.3°. Similarly, in the allotment of the Paskov Mine, an area unsuitable for founding structures was determined to the distance of 500 m from the panel's edge, for which the corresponding break angle is 50.2°. This demarcation may be implemented prior to deposit mining being aware of several physical-mechanical parameters of rocks in the deposit's overburden. Having mined out a particular section of a deposit, it is recommended to verify the values of break angle using the method described herein. The study may be applied as a relatively fast and effective method to evaluate future land use for planning.  相似文献   
393.
Environmental Science and Pollution Research - In this work, we present the application of solar photocatalysis for air purification including toxic substances such as ammonia and methane normally...  相似文献   
394.
PBDEs were measured in air and soil across Azerbaijan to establish contemporary concentrations at 13 urban and rural sites. Polyurethane foam passive air samplers (PUF-PAS) were deployed for a period of a month with surface soil samples collected at the same sites. Unlike organochlorine pesticides previously surveyed by our group, PBDE concentrations in both contemporary air and soil were low in comparison to recent European and Asian studies. For example, mean ∑9PBDE concentrations in air and soil were 7.13 ± 1.66 pg m?3 and 168 ± 57 pg g?1, respectively. The fully brominated BDE-209 was the most abundant congener observed in soil (174.8 ± 58.5 pg g?1), comprising ~ 96% of ∑10PBDE. However, the PAS-derived air concentrations for highly brominated congeners must be viewed with caution as there is uncertainty over the uptake rates of particle-bound chemicals using these devices. Some of the highest concentrations in air were observed at sites with the highest wind speeds and at several remote locations in the north of the country and this requires further research. Levels of BDE-47 and 99 (the two most abundant congeners in the widely used penta-formulation) were lower than levels reported elsewhere suggesting limited use/import of the penta-BDE formulation in Azerbaijan.  相似文献   
395.
The structure and design of future urban development can have significant adverse effects on air pollutant emissions as well as other environmental factors. When considering the future impact of growth on mobile source emissions, we generally model the increase in vehicle kilometers traveled (VKT) as a function of population growth. However, diverse and poorly planned urban development (i.e., urban sprawl) can force higher rates of motor vehicle use and in return increase levels of pollutant emissions than alternative land-use scenarios. The objective of this study is to develop and implement an air quality assessment tool that takes into account the influence of alternative growth and development scenarios on air quality.The use of scenario-based techniques in land use planning has been around since the late 1940s and been tested in many different applications to aid in decision-making. In this study, we introduce the development of an advanced interactive scenario-based land use and atmospheric chemistry modeling system coupled with a GIS (Geographical Information System) framework. The modeling system is designed to be modular and includes land use/land cover information, transportation, meteorological, emissions, and photochemical modeling components. The methods and modularity of the developed system allow its application to both broad areas and applications.To investigate the impact of possible land use change and urbanization, we evaluated a set of alternative future patterns of land use developed for a study area in Southwest California. Four land use and two population variants (increases of 500k and 1M) were considered. Overall, a Regional Low-Density Future was seen to have the highest pollutant emissions, largest increase in VKT, and the greatest impact on air quality. On the other hand, a Three-Centers Future appeared to be the most beneficial alternative future land-use scenario in terms of air quality. For all cases, the increase in population was the main factor leading to the change on predicted pollutant levels.  相似文献   
396.
We assessed human impacts on ecosystems by calculating the proportion of aboveground net primary production appropriated by humans (aHANPP) in the territory of the Czech Republic. The human appropriation of aboveground net primary production reached 21.5 Tg C per year in 2006 or 56% of the annual potential natural productivity. Harvested productivity equivalent aNPPH is contributing to the overall appropriation of photosynthetic production by 80%. Considerable productivity losses have been induced by agricultural land conversion and urbanization. While artificial surfaces are responsible for the appropriation of whole ecosystem production, productivity of urban green areas and managed forests can even exceed natural productivity levels. In the period 1990–2000, the aHANPP dropped by 7%, but the indicator shows an increase by over 2% in the period 2000–2006. The indicator of human appropriation of net primary production enables translation of land cover changes into measures of ecosystem services affected by human activities. We found aHANPP to be a suitable indicator of human impacts on ecosystems, as it detects trends and enables spatial mapping of human impacts.  相似文献   
397.
There is a growing interest for the application of biomakers to field-collected earthworms. Therefore we have evaluated the usability of native populations of endogeic, widely distributed earthworm Aporrectodea caliginosa in the assessment of soil genotoxicity using the Comet assay. Validation of the Comet assay on earthworm coelomocytes has been established using commercially available Eisenia fetida exposed to copper, cadmium, and pentachlorophenol, along with A. caliginosa exposed to copper in a filter paper contact test. Neutral red retention time (NRRT) assay was conducted on copper exposed and field-collected earthworms. Significant DNA and lysosomal damage was measured using Comet and NRRT assays in native populations of A. caliginosa sampled from the polluted soils in the urban area in comparison to the earthworms from the reference site. The results of this study confirm the employment of A. caliginosa as a suitable species for the in situ soil toxicity and genotoxicity field surveys.  相似文献   
398.
Contamination by microscopic fungi and mycotoxins in different bee pollen samples, which were stored under three different ways of storing as freezing, drying and UV radiation, was investigated. During spring 2009, 45 samples of bee-collected pollen were gathered from beekeepers who placed their bee colonies on monocultures of sunflower, rape and poppy fields within their flying distance. Bee pollen was collected from bees' legs by special devices placed at the entrance to hives. Samples were examined for the concentration and identification of microscopic fungi able to grow on Malt and Czapek-Dox agar and mycotoxins content [deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZON) and total aflatoxins (AFL), fumonisins (FUM), ochratoxins (OTA)] by direct competitive enzyme-linked immunosorbent assays (ELISA). The total number of microscopic fungi in this study ranged from 2.98 ± 0.02 in frozen sunflower bee pollen to 4.06 ± 0.10 log cfu.g(-1) in sunflower bee pollen after UV radiation. In this study, 449 isolates belonging to 21 fungal species representing 9 genera were found in 45 samples of bee pollen. The total isolates were detected in frozen poppy pollen 29, rape pollen 40, sunflower pollen 80, in dried poppy pollen 12, rape pollen 36, sunflower 78, in poppy pollen after UV radiation treatment 54, rape 59 and sunflower 58. The most frequent isolates of microscopic fungi found in bee pollen samples of all prevalent species were Mucor mucedo (49 isolates), Alternaria alternata (40 isolates), Mucor hiemalis (40 isolates), Aspergillus fumigatus (33 isolates) and Cladosporium cladosporioides (31 isolates). The most frequently found isolates were detected in sunflower bee pollen frozen (80 isolates) and the lowest number of isolates was observed in poppy bee pollen dried (12 isolates). The most prevalent mycotoxin of poppy bee pollen was ZON (361.55 ± 0.26 μg.kg(-1)), in rape bee pollen T-2 toxin (265.40 ± 0.18 μg.kg(-1)) and in sunflower bee pollen T-2 toxin (364.72 ± 0.13 μg.kg(-1)) in all cases in frozen samples.  相似文献   
399.
This study aimed at investigating the cellular distribution of Hg in the lichens Cladonia arbuscula subsp. mitis and Peltigera rufescens treated with Hg2+ and at testing if Hg treatment affects selected physiological parameters. In both species, increasing Hg accumulation under increasing Hg supply in the treatment solutions was found. P. rufescens showed a higher intracellular accumulation. Photosynthetic parameters were negatively affected in both species, as indicated by the decrease in photosynthetic pigments content, photosynthetic efficiency and chlorophyll integrity. Cell membranes of both species endured damage as indicated by the increase in the concentration of products of lipid peroxidation and decrease in ergosterol content. Nevertheless, differences between the two species were found, suggesting a differential sensitivity to Hg.  相似文献   
400.
The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polybrominated diphenylethers (PBDEs) in 33 breast milk samples collected in 2006-2007 from primipara mothers close to four industrial areas of Slovak Republic were determined. The total PCDDs/PCDFs and dl-PCBs expressed as TEQ based on WHO TEFs 1998 in breast milk samples varied from 5.0 to 51.8 pg g−1 fat (median: 13.1 pg g−1 fat; mean: 18.0 pg g−1 fat). The measurements of seven PBDE congeners (IUPAC No. 28, 47, 99, 100, 153, 154, and 183) were performed for the first time in human milk from Slovakia. PBDE levels ranged between 0.22 and 1.62 ng g−1 fat, with median and mean value of 0.43 ng g−1 fat and 0.57 ng g−1 fat respectively. No statistically significant differences were observed between studied areas in total PBDE concentrations.Furthermore, this study presents first results concerning the daily intake (DI) of PCDDs/PCDFs and dioxin-like compounds for the most vulnerable breast-fed infant population in Slovakia. The total PCDD/PCDF and dl-PCB DI for an infant during the first 2 months of life was estimated in a range from 14.4 to 230 pg TEQ kg−1 b.w., with a median value of 58.9 pg TEQ kg−1 b.w.. The DI values substantially exceeded the tolerable daily intake (TDI) 1-4 pg TEQ kg−1 b.w. recommended by WHO. The dietary infant intake concerning PBDEs was estimated to be between 0.69 and 7.1 ng kg−1 b.w. d−1, with median value of 1.7 ng kg−1 b.w. d−1.  相似文献   
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