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51.
Despite enthusiasm about new gas reserves, shale gas has not come to Poland without controversies. This study examines how shale gas has been framed as a public issue by political and business elites, experts, local communities and civil society organizations. Through a frame analysis, we found three main frames about shale gas: shale gas as a novel economic resource, as a strategic resource for energy security and as a threat. However, only the first two frames, proposed by political and business elites, have shaped the policy process. The third frame, constructed by local actors and civil society groups, has had minimal impact. We explain this exclusion drawing on the deficit model of risk communication. This approach reveals that Polish experts, and business and political actors, during their interactions with local groups, have framed proponents of the threat frame as ‘incompetent actors’ effectively excluding the threat frame from policy processes. 相似文献
52.
The secondary cell wall structure of tracheids of Scots pine (Pinus sylvestris L.), especially the angle of microfibrils in the S(2) layer, was examined in wood deposited prior to and after the Chernobyl accident in 1986. Microscopic analysis was carried out on wood samples collected in October 1997 from breast height of three pine trees 16, 30 and 42 years old. The polluted site was located in a distance of 5 km south from the Chernobyl nuclear power plant where radioactive contamination in 1997 was 3.7 x 10(5) kBq m(-2). Anatomical analysis showed that the structure of the secondary cell wall in tracheids formed after the Chernobyl accident was changed. Changes occurred both in S(2) and S(3) layers. The angle of microfibrils in S(2) layer in wood deposited after the Chernobyl accident was different in comparison to this measured in wood formed prior to the disaster. The intensity of the changes, i.e. alteration of the microfibrils angle in S(2) layer and unusual pattern of the S(3) layer, depended on the age of the tree and was most intensive in a young tree. 相似文献
53.
Fox A Harley W Feigley C Salzberg D Sebastian A Larsson L 《Journal of environmental monitoring : JEM》2003,5(2):246-252
Our group previously demonstrated that carbon dioxide (CO2) levels in heavily occupied schools correlate with the levels of airborne bacterial markers. Since CO2 is derived from the room occupants, it was hypothesized that in schools, bacterial markers may be primarily increased in indoor air because of the presence of children; directly from skin microflora or indirectly, by stirring up dust from carpets and other sources. The purpose of this project was to test the hypothesis. Muramic acid (Mur) is found in almost all bacteria whereas 3-hydroxy fatty acids (3-OH FAs) are found only in Gram-negative bacteria. Thus Mur and 3-OH FA serve as markers to assess bacterial levels in indoor air (pmol m(-3)). In our previous school studies, airborne dust was collected only from occupied rooms. However, in the present study, additional dust samples were collected from the same rooms each weekend when unoccupied. Samples were also collected from outside air. The levels of dust, Mur and C10:0, C12:0, C14:0, and C16:0 3-OH FAs were each much higher (range 5-50 fold) in occupied rooms than in unoccupied school rooms. Levels in outdoor air were much lower than that of indoor air from occupied classrooms and higher than the levels in the same rooms when unoccupied. The mean CO2 concentrations were around 420 parts per million (ppm) in unoccupied rooms and outside air; and they ranged from 1017 to 1736 ppm in occupied rooms, regularly exceeding 800-1000 ppm, which are the maximum levels indicative of adequate indoor ventilation. This indicates that the children were responsible for the increased levels of bacterial markers. However, the concentration of Mur in dust was also 6 fold higher in occupied rooms (115.5 versus 18.2 pmole mg(-1)). This further suggests that airborne dust present in occupied and unoccupied rooms is quite distinct. In conclusion in unoccupied rooms, the dust was of environmental origin but the children were the primary source in occupied rooms. 相似文献
54.
The Baltic Sea spring phytoplankton bloom in a changing climate: an experimental approach 总被引:1,自引:0,他引:1
Ulrich Sommer Nicole Aberle Kathrin Lengfellner Aleksandra Lewandowska 《Marine Biology》2012,159(11):2479-2490
The response of the Baltic Sea spring bloom was studied in mesocosm experiments, where temperatures were elevated up to 6°C above the present-day sea surface temperature of the spring bloom season. Four of the seven experiments were carried out at different light levels (32–202?Wh?m?2 at the start of the experiments) in the different experimental years. In one further experiment, the factors light and temperature were crossed, and in one experiment, the factors density of overwintering zooplankton and temperature were crossed. Overall, there was a slight temporal acceleration of the phytoplankton spring bloom, a decline of peak biomass and a decline of mean cell size with warming. The temperature influence on phytoplankton bloom timing, biomass and size structure was qualitatively highly robust across experiments. The dependence of timing, biomass, and size structure on initial conditions was tested by multiple regression analysis of the y-temperature regressions with the candidate independent variables initial light, initial phytoplankton biomass, initial microzooplankton biomass, and initial mesozooplankton (=copepod) biomass. The bloom timing predicted for mean temperatures (5.28°C) depended on light. The peak biomass showed a strong positive dependence on light and a weaker negative dependence on initial copepod density. Mean phytoplankton cell size predicted for the mean temperature responded positively to light and negatively to copepod density. The anticipated mismatch between phytoplankton supply and food demand by newly hatched copepod nauplii occurred only under the combination of low light and warm temperatures. The analysis presented here confirms earlier conclusions about temperature responses that are based on subsets of our experimental series. However, only the comprehensive analysis across all experiments highlights the importance of the factor light. 相似文献
55.
Karla Ili&cacute &Dstrok ur&dstrok i&cacute Raluca Ostafe Olivera Prodanovi&cacute Aleksandra &Dstrok ur&dstrok evi&cacute &Dstrok elma Nikolina Popovi&cacute Rainer Fischer Stefan Schillberg Radivoje Prodanovi&cacute 《Frontiers of Environmental Science & Engineering》2021,15(2):19
56.
Aleksandra Wilk Elżbieta Kalisińska Danuta I. Kosik-Bogacka Maciej Romanowski Jacek Różański Kazimierz Ciechanowski Marcin Słojewski Natalia Łanocha-Arendarczyk 《Environmental geochemistry and health》2017,39(4):889-899
Heavy metals, including cadmium (Cd), lead (Pb) and mercury (Hg) act as nephrotoxic agents, particularly in the renal cortex. The aim of the study was to determine the concentrations of Cd, Pb and Hg in kidneys removed from patients due to lesions of various etiologies and from patients after the rejection of transplanted kidneys. Additionally, we determined the influence of selected biological and environmental factors on the concentrations of toxic metals. The study material consisted of kidneys with tumor lesions (n = 27), without tumors (n = 7) and its extracted grafts (n = 10) obtained from patients belongs to the north-western areas of Poland. The determined metal concentrations in the renal cortex and medulla may be arranged in the following descending order: Cd > Pb > Hg. The highest concentrations of Cd and Hg were found in the cortex, while the maximum content Pb was observed in the medulla. Significant correlations were found in the concentrations of the same metals between cortex and medulla and between Pb and Hg in the renal medulla. Pb content was higher in the renal medulla of men than in the cortex of the elderly (above 60 years of age). The highest concentrations of Pb and Hg were found in the cortex and medulla, of the kidneys had not neoplastic changes, and lower content of these metals were found in the extracted kidney grafts. In summary, renal grafts accumulate less heavy metals than cancerous kidneys, what could have been caused by immunosuppressors taken by the graft recipients. Moreover, sex, age and smoking are key factors responsible for xenobiotics concentrations. 相似文献
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58.
Vasić MV Mihailović A Kozmidis-Luburić U Nemes T Ninkov J Zeremski-Škorić T Antić B 《Chemosphere》2012,86(6):585-592
Snow samples were collected near crossroads in Novi Sad, Serbia, during December 2009 to assess metal concentrations (Ca, K, Zn, Fe, Cu, Mn, Al, Pb and Na), fine particle distribution and pH value. The filtered samples of melted snow were analysed, with a focus on particles smaller than a few μm. The most common values of the frequency number distribution curve were either in the range of 0.05-0.07 μm or one order of magnitude higher (0.2-0.5 μm). At examined locations metal concentrations varied from 0.0004 mg L−1 for Pb to 18.9 mg L−1 for Na. Besides Na, which mostly originated from de-icing salt, Ca is found to be the most abundant element in snow indicating the dominant influence of natural factors on snow chemistry. No significant difference was found in concentration of the elements at locations near crossroads with either low or high traffic volume, except for Na and Zn.To investigate how metals were related a correlation analysis was done for the concentrations of metals and with respect to the particle size distribution parameters and pH values. The major influence on the fine particle volume (mass) was concluded to be due to the elements from anthropogenic sources. This conclusion was based on the significant positive correlation between Fe, Zn and Al and the fine particle volume based distribution parameters. 相似文献
59.
Samecka-Cymerman A Kolon K Mróz L Kempers AJ 《Environmental monitoring and assessment》2012,184(10):6357-6365
Concentrations of the elements Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in the fronds of the fern Athyrium distentifolium from the Sudety and Tatra mountains (Poland). The A. distentifolium sites in the Sudety mountains which were influenced by long-range metal transport from the former Black Triangle were distinguished by the principal component and classification analysis (PCCA). These sites were situated on the west side slopes of one of the ranges in the Sudety mountains (within a 150-km radius of the heart of the former Black Triangle) at an altitude of 700 m asl, and exposed to prevailing winds. This most affected area had significantly higher foliar concentrations of Cu, Cr and Ni which are typical for long-range transported airborne elements occurring in coal fly ash emitted by lignite combustion industry. 相似文献
60.
Zujić AM Radak BB Filipović AJ Marković DA 《Environmental monitoring and assessment》2009,156(1-4):539-549
Although there are tendencies to develop a single common index which would describe an overall air quality status within an area, constructed from a choice of measurements of individual pollutants, indices describing individual pollutants themselves have several potentials which can be used in ways which are not possible with pollutant concentrations. On the case of Belgrade, Serbia, we investigated possibilities of using such indices for comparisons between pollutants, characterization of monitoring sites, and extending their use to include elements of population exposure. A methodology of adjusting the results obtained at monitoring stations located in severe pollution conditions, like street canyons, is proposed and used. 相似文献