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1.
Progress in the greening of UK local government has been hampered by uncertainty about the relationship between resource use and environmental protection. Ecological modernizationmay offer the most appropriateparadigm to reconcile economic, social and environmentalinterpretationsof sustainability. The transition from corporate to strategic environmental management currently being attempted by some 'green' authorities can be construed as an attempt to promote ecological modernization in the form of institutional learning. Fife Council in Scotland provides an interesting case study. Progress with corporate environmental management has become bound up with a radical devolution of decision making. Efforts to link the authority's Sustainable Development Policy to a Local Agenda 21 programme have been initiated with the piloting of sustainability indicators.  相似文献   
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Abstract

Toxicity of heavy metals to living organisms is a worldwide research topic. Although, much has been discovered about cadmium and nickel impact on biological systems, a lot still remains unclear. We used inductively coupled plasma – optical emission spectroscopy to address the question of the effect of two different heavy metals nickel, and cadmium on intracellular ion balance. Increase or decrease of the content of several essential cations including Ca2+, Na+, K+, Mg2+, Cu2+, Fe3+ in the yeast Schizosaccharomyces pombe was determined. Our results revealed that the cell exposure to high nickel and cadmium concentrations led to significant elevation of Ca2+, Na+, Mg2+, Cu2+, Fe3+ levels in the yeast cell, while the content of K+ decreased. Correlation analyses showing in the presence of nickel and cadmium strong positive correlation among each tested element (Ca2+, Na+, Cu2+, Mg2+ and Fe3+) except for K+, demonstrate the significant impact of heavy metal treatment to ion homeostasis of the cell. Our data indicate that acute nickel and cadmium contamination leads to substantial ionome misbalance in yeast.  相似文献   
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Since 1994 the nickel-processing plant at the Cu-Ni smelter at Harjavalta, south-west Finland, has emitted considerable amounts of NH(3) into the atmosphere. The effects of NH(3) emissions on nitrogen and sulphur deposition in throughfall and the foliar nutrient status were investigated in a Scots pine stand at 0.5 km distance. Bulk deposition, stand throughfall and percolation water (20 cm depth) samples were collected at 4-week intervals during 1992-1998. pH and the Ca, Mg, K, NH(4) and SO(4) concentrations were determined on the samples. NH(3) emissions have strongly increased the scavenging of SO(2) from the air in the pine stand, and the increased levels of N and S deposition were clearly evident as increased foliar N and S concentrations and larger needle size. The increased input of SO(4) into the forest floor was not associated with an increase in the leaching of Ca and Mg from the surface soil layers.  相似文献   
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Mature specimens of Parasol Mushroom were collected annually in the outskirts of the Siemiany (2000-2003) and Rafa (2001-2003) sites in the northern part of Poland to examine temporal variations and similarities in the composition of 20 chemical elements. Analysis was done under the same condition and using well-validated analytical methods. Elements were determined by inductively coupled plasma-atomic emission spectroscopy and cold vapour-atomic absorption spectroscopy (Hg). The ranges of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn concentrations in the caps of fruiting bodies were similar (p > 0.05; Mann-Whitney U test) for both geographically distant sites, and these specimens from Rafa were more contaminated with Pb (p < 0.05; Mann-Whitney U test). The annual collections of caps in the Siemiany site varied in Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, Na, Rb and Sr and contents (0.05 < p < 0.001), while they were similar in Cr, K, Mg, Mn, Ni, P, Pb and Zn (p > 0.05; Mann-Whitney U test). The annual collections of specimens from the Rafa site varied in contents of Ag, Al, Ba, Ca, Fe, Hg, K, Mg, Mn, P, Rb and Zn (p > 0.05), while they were similar in Cd, Co, Cr, Cu, Na, Ni, Pb and Sr (p < 0.05). The results of this study imply that metallic elements content of Parasol Mushroom collected at the same undisrupted sites, and hence keeping the same geochemical condition for mushroom development and fructification (the same stands and probably the same mycelia), can fluctuate over the years or the life-span of mycelium. Hence, when assessing the nutritional value of essential metallic elements and status of non-essential or toxic metallic elements in Parasol's Mushroom caps (and probably also of other mushrooms species) to man, the possible fluctuation in contents over time have to be taken into account.  相似文献   
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Surface soils were collected at remote, urban and industrial sites in the Southern of Italy in order to evaluate PAH concentrations and assess the toxic effects by a battery of ecotoxicological tests. The tests were performed on whole soils and on both organic and aqueous extracts. Further goal of this study was to integrate the results coming from each test and matrix in a synthetic toxicity index. The highest summation sigmaPAH concentrations were measured at the industrial soil, although this one did not show an high ecotoxicological risk. Among the performed tests, the phytotoxicity tests showed the highest sensitivity. For whole soil, the worst case always has been represented by test through bacteria. Our results could represent the first step toward the selection of a proper battery to characterize the soil ecotoxicological risk.  相似文献   
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ABSTRACT

This study investigated medical waste practices used by hospitals in Oregon, Washington, and Idaho, which includes the majority of hospitals in the U.S. Environmental Protection Agency's (EPA) Region 10. During the fall of 1993, 225 hospitals were surveyed with a response rate of 72.5%. The results reported here focus on infectious waste segregation practices, medical waste treatment and disposal practices, and the operating status of hospital incinerators in these three states. Hospitals were provided a definition of medical waste in the survey, but were queried about how they define infectious waste. The results implied that there was no consensus about which agency or organization's definition of infectious waste should be used in their waste management programs. Confusion around the definition of infectious waste may also have contributed to the finding that almost half of the hospitals are not segregating infectious waste from other medical waste. The most frequently used practice of treating and disposing of medical waste was the use of private haulers that transport medical waste to treatment facilities (61.5%). The next most frequently reported techniques were pouring into municipal sewage (46.6%), depositing in landfills (41.6%), and autoclaving (32.3%). Other methods adopted by hospitals included Electro-Thermal-Deac-tivation (ETD), hydropulping, microwaving, and grinding before pouring into the municipal sewer. Hospitals were asked to identify all methods they used in the treatment and disposal of medical waste. Percentages, therefore, add up to greater than 100% because the majority chose more than one method. Hospitals in Oregon and Washington used microwaving and ETD methods to treat medical waste, while those in Idaho did not. No hospitals in any of the states reported using irradiation as a treatment technique. Most hospitals in Oregon and Washington no longer operate their incinerators due to more stringent regulations regarding air pollution emissions. Hospitals in Idaho, however, were still operating incinerators in the absence of state regulations specific to these types of facilities.  相似文献   
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Surface ozone concentrations in southern Africa exceed air quality guidelines set to protect agricultural crops. This paper addresses a knowledge gap by performing a preliminary assessment of potential ozone impacts on vegetation in southern African. Maize (Zea mays L.) is the receptor of interest in the main maize producing countries, i.e. South Africa, Zambia and Zimbabwe. Surface ozone concentrations are estimated for the growing season (October to April) using photochemical modelling. Hourly mean modelled ozone concentrations ranged between 19.7 and 31.2 ppb, while maximums range between 28.9 and 61.9 ppb, and are near 30 ppb over South Africa and Zambia, while in Zimbabwe, they exceed 40 ppb and translate into monthly AOT40 values of over 3,000 ppb h in five of the seven months of the growing season. This study suggests that surface ozone may pose a threat to agricultural production in southern African, particularly in Zimbabwe.  相似文献   
10.
Odsjö T  Roos A  Johnels AG 《Ambio》2004,33(3):133-137
The tail feathers of 104 osprey nestlings (Pandion haliaetus) from Lake Asnen, southern Sweden, were analyzed for total mercury and selenium content. Concentrations of mercury in feathers from the western part of the lake fell during the period 1969-1998, when pollution from industrial mercury had decreased and a paper mill upstream of the lake was closed down in 1979. Nestlings from the eastern part of the lake had initially lower levels of mercury, predominantly from atmospheric fallout. The levels did not decrease during the period. The reason for the differences seems to be the limited water flow between the western and the eastern part of the lake. The selenium concentrations were constant over time and approximately the same in both parts of the lake. The total-Hg/Se ratio in the western part of the lake was 2.94, which is somewhat higher than the 1:1 molar ratio constant (2.54). This indicates that the bioaccumulated quantity of selenium which is thought to be protective for the organisms against the toxic effects of mercury, is somewhat insufficient to bind all body mercury.  相似文献   
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