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641.
The air quality management (AQM) framework in the UK is a risk management approach using effects-based objectives for air pollutants to determine the need for action. The Environment Act 1995 required a National Air Quality Strategy to be published, setting out health-based standards and objectives for eight pollutants, of which seven are to managed at a local scale. Because of the variety of sources of air pollution, if the AQM process is to succeed in the long term, solutions to identified problems will be required from transport, land use and economic planning sectors of local government in liaison with various other agencies, regulators and outside bodies. As such the task is inherently multi-disciplinary and an integrated, collaborative approach will be necessary. Although this observation is now fairly well documented, there is still little guidance relating to how, in relation to air quality management, integration can actually be accomplished. This paper presents some observations from case studies undertaken as part of a longer-term research study and in particular focuses on the identified problems of involving non-air-quality professionals in a highly technical scientific process. Various approaches to the collaborative aspects of air quality management will be presented. These case studies represent local authorities of different sizes in different political and organisational situations facing a range of air quality challenges. The creation of project teams or task forces is judged particularly useful for local air quality management. Methods that could be applied more widely include appointing individuals as integrators, and rotation of key personnel.  相似文献   
642.
ABSTRACT: As part of the Comprehensive Everglades Restoration Plan (CERP), various water supply projects have been proposed in a region located between the Miami metropolitan area and the extensive regional wetland systems that are part of the Everglades or remnant Everglades. A ground water flow model of the surficial aquifer within northern Miami‐Dade County was constructed using MODFLOW to evaluate the effects of these projects on water levels in the wetlands and the underlying surficial aquifer. The new Wetlands package was used to conjunctively simulate overland flow through these wetlands and the shallow ground water system. Comparisons of simulated to measured ground water levels and wetland stages were very satisfactory, where computed and measured water levels agreed within 0.5 ft over most of the period of record at nearly all of the monitoring sites. Temporal trends in water levels were also replicated. It was concluded that the assumptions and methodologies inherent to the Wetlands package were suitable for simulating regional wetland hydrology within the Everglades area.  相似文献   
643.
The BIOMASS Theme 1 project has developed a methodology for the logical and defensible construction of 'assessment biospheres': mathematical representations of biospheres used in the total system performance assessment of radioactive waste disposal. The BIOMASS Methodology provides a systematic approach to decision making, including decisions on how to address biosphere change. The BIOMASS Methodology was developed through consultation and collaboration with many relevant organisations, including regulators, operators and a variety of independent experts. It has been developed to be practical and to be consistent with recommendations from ICRP and IAEA on radiation protection in the context of the disposal of long-lived solid radioactive wastes. The five main steps in the methodology are described in this paper. The importance of a clear assessment context, to clarify intentions and to support a coherent biosphere assessment process within an overall repository performance assessment, is strongly emphasised. A well described assessment context is an important tool for ensuring consistency across the performance assessment as a whole. The use of interaction matrices has been found to be helpful in clarifying the interactions between different habitats within the biosphere system and the significant radionuclide transfer pathways within the biosphere system. Matrices also provide a useful means of checking for consistency.  相似文献   
644.
Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses.  相似文献   
645.
The objectives of this study were to evaluate metal contamination of drinking water resulting from the corrosion of distribution pipes and its significance to human health. A community in Dhahran, which is served from its own desalination facilities, was chosen for this study. About 150 drinking water samples were collected and analyzed for metal concentrations using an inductively coupled argon plasma analyzer. It was found that copper, iron and zinc in the drinking water increased during its transportation from the desalination plant to the consumers. This increase was related to the length and material of distribution pipes. Concentrations of copper and zinc were increased during overnight storage of water in the appliances. Metal concentrations found in this study are discussed with reference to human health.  相似文献   
646.
The environmental degradation caused by industrial agriculture, as well as the resulting social and health consequences, creates an urgency to rethink food production by expanding the moral imagination to include agricultural practices. Agricultural practices presume human use of the earth and acknowledge human dependence on the biotic community, and these relations mean that agriculture presents a separate set of considerations in the broader field of environmental ethics. Many scholars and activists have argued persuasively that we need new stories to rethink agricultural practice, however, the link—the story that does and can shape agricultural practice—has not yet been fully articulated in environmental discourse. My analysis explores how language has shaped existing agricultural models and, more important, the potential of story to influence agricultural practice. To do this, I draw upon cognitive theory to illustrate how metaphoric and narrative language structures thought and influences practice, beginning with my contention that industrial agriculture relies on a discourse of mechanistic relations between humans and a passive earth, language that has naturalized the chemically intensive monocultures prevalent in much of the American Midwest. However, alternative agricultures, including organic agriculture, agro-ecology, and ecological agriculture, emphasize qualities such as interdependence and reciprocity and do so as a deliberate response to the perceived inadequacies of industrial agriculture and its governing narrative. Exploring the different discourses of agricultural systems can help us think through different modalities for human relations with the biotic community and demonstrate story’s potential role in altering practice.  相似文献   
647.
Field investigations were performed in 1984-1985 on the effects of acidity level in simulated rain on disease dynamics in four pathosystems: alfalfa leaf spot (ALS), peanut leaf spot (PLS), potato late blight (PLB), and soybean brown spot (SBS). Studies were performed in an ambient rain exclusion apparatus with simulated rain acidity levels of pH 2.8, 3.6, 4.2, 4.8, or 5.6 and four plots per pH level. In 1984 for ALS and PLB, rain was simulated three times a week at 6-8 mm per event. For PLS and SBS in 1984 and for PLB, PLS, and SBS in 1985, rain was simulated twice a week at 13-16 mm per event with a 10 min pause halfway through each event. Disease was assessed three times a week. In 1984, no significant effect of acidity level in simulated rain on disease severity was detected in any pathosystem. Severity of PLB differed among treatments in 1985 with significant quadratic and cubic components for the dose-response relationship. PLS severity decreased with increasing level of acidity in simulated rain in 1985 and the dose-response relationship was linear. No differences in severity of ALS or SBS due to acidity of simulated rain were found. Thus, disease response to acidity of simulated rain is system dependent.  相似文献   
648.
Laboratory experiments to quantify the global production of NOx (NO + NO2) in the troposphere due to atmospheric lightning and biogenic activity in soil are presented. These laboratory experiments, as well as other studies, suggest that the global production of NOx by lightning probably ranges between 2 and 20 MT(N)y-1 of NO and is strongly dependent on the total energy deposited by lightning, a quantity not well-known. In our laboratory experiments, nitrifying micro-organisms is soil were found to be a significant source of both NO and nitrous oxide (N2O). The measured production ratio of NO to N2O averaged 2-3 for oxygen partial pressures of 0.5-10%. Extrapolating these laboratory measurements to the global scale, which is somewhat risky, suggests that nitrifying micro-organisms in soil may account for as much as 10 MT(N) y-1 of NO. Additional experiments with denitrifying micro-organisms gave an NO to N2O production ratio ranging from 2 to 4 for an oxygen partial pressure of 0.5% and a ratio of less than unity for oxygen partial pressures ranging from 1 to 20%. The production of NO and N2O, normalized with respect to micro-organism number indicates that the production of both NO and N2O by denitrifying micro-organisms is at least an order of magnitude less than production by nitrifying micro-organisms for the micro-organisms studied.  相似文献   
649.
In the periods of summer and autumn bloom of the Stephanodiscus hantzschii Crun. in recreational water bodies, studies on the vertical distribution of chlorophyll a, its contents per unit biomass, efficiency in using photosynthetically active radiation (EPhAR), and assimilative activity of microalgae were performed. The results confirmed the existence of two ecophysiological forms of St. hantzschii and provided evidence that both forms are typically autotrophic and can efficiently use low-intensity PhAR for photosynthesis.  相似文献   
650.
Activity development of key groups of enzymes involved in municipal refuse decomposition was measured in laboratory landfill bioreactors with and without leachate recycling and inoculation for about 210 days.The results showed that the enzymes(amylase,protease,cellulase,lipase and pectinase)were present in fresh refuse but at low values and positively affected by leachate recycling and refuse inoculation.The total average of cellulase activity in digesters D3 operated with leachate recycling but no inoculation,D4 and D5 operated with leachate recyling and inoculation was much higher than that in digesters D1 and D2 without leachate recycling and inoculation by 88%-127%,117%-162%and 64%-98%.The total average of protease activity was higher in digester D4 than that in digesters D1,D2,D3and D5 by 63%,39%,24%and 24%,respectively,and the positive effect of leachate recycling and inoculation on protease activity of landfilled refuse mainly was at the first two months.The total average of amylase activity was higher in digesters D3,D4 and D5 than that in digesters D1 and D2 by 83%-132%,96%-148%and 81%-129%.During the early phase of incubation,the stimulatory effect of inoculation on lipase activity was measured,but refuse moisture was the main factor affecting lipase activity of landfilled refuse.The inoculation,initial and continuous inoculation of microorganisms existing in leachate,was the mainly stimulatory factor affecting pectinase activity of landfilled refuse.  相似文献   
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