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701.
Across the United Kingdom, the majority of local authoritieshave now completed their first phase of local air qualityreview and assessment work, as required under the AirQuality Strategy for England, Scotland, Wales and NorthernIreland (DETR, 2000a). Emerging from this first phasework is an anticipated suite of over 110 Air QualityManagement Areas (AQMAs). These areas are identifiedlocations where one or more of the national air qualityobjectives are predicted to exceed by specific target dates,and their spatial extent and shape is emerging as highlyvariable. Local authorities are guided to use a variety ofscientific tools to underpin the scientific assessments, anda consideration of uncertainty in both the tools used andsubsequent delineation of AQMAs is likely to affect theemerging management areas significantly. With subsidiarity underpinning the process of local air qualitymanagement (LAQM), local decision-making is anticipated toinfluence the outcome of the LAQM process in its entirety,with the declaration of AQMAs necessitating the preparationand implementation of air quality action plans. UKexperience of the effective management of local air quality,through the designation of AQMAs, demonstrates a valuableframework for other European countries developing mechanismsto manage air quality locally.  相似文献   
702.
Biological Pollutants: Alien Fishes in Mountain Lakes   总被引:2,自引:0,他引:2  
Many lakes in the national parks of the Canadian Rockies were stocked with alien fish species in the early to mid 20th century. Changes to Parks Canada's mandate require the original communities of these lakes to be restored. We document the changes to invertebrate communities caused by the stocking of alien fishes into three fishless alpine lakes, and describe the results of two restoration experiments, one the reintroduction of Hesperodiaptomus arcticus, a planktonic predator that had been eliminated from Snowflake Lake by stocked fish, and the other the removal of brook trout (Salvelinus fontinalis) from Bighorn Lake. In both cases, there were great changes to the zooplankton communities, which required several years to complete, probably because of the cold water and unproductive nature of the lakes. Many of the invertebrate species extirpated by stocked alien fishes co-exist with native fish species in nearby lakes. Possible reasons are discussed.  相似文献   
703.
The incorporation of sustainability assessment into decision-making processes is a key task for water service providers in the UK and elsewhere. This paper describes the development and application of a set of sustainability criteria, which have been developed and tested with project partners in the UK and Romania. They will be used in a 'guidebook' that will set out a framework to facilitate the inclusion of sustainability in the decision-making process. This work is part of the Sustainable Water Industry Asset Resource Decisions project to develop a multi-criteria analysis decision support system to assist water service providers to assess the relative sustainability of water/wastewater system asset development decisions.  相似文献   
704.
Trends in the Water Chemistry of High Altitude Lakes in Europe   总被引:2,自引:0,他引:2  
Mosello  R.  Lami  A.  Marchetto  A.  Rogora  M.  Wathne  B.  Lien  L.  Catalan  J.  Camarero  L.  Ventura  M.  Psenner  R.  Koinig  K.  Thies  H.  Sommaruga-Wögrath  S.  Nickus  U.  Tait  D.  Thaler  B.  Barbieri  A.  Harriman  R. 《Water, Air, & Soil Pollution: Focus》2002,2(2):75-89
Here we present the chemical trends of seven high altitude lakes, analysed within the AL:PE and MOLAR Projects of the EU (1999) and selected on the basis of the availability of complete and reliable data for the period 1984–1999. The lakes are representative of the Scandinavian Alps, the Cairngorm Mountains in Scotland, the Alps and the Pyrenees. Significant trends were identified for some indicators of acidification, for instance pH and alkalinity, but not all lakes reacted similarly to decreasing depositions of sulphate and base cations. Differences in lake response are discussed in relation to recent variations of atmospheric deposition chemistry and associated changes in climatic conditions. Beside individual variations of the studied lakes, depending, among other things, on altitude and morphology, catchment characteristics and climate trends play a major role for the reaction of high altitude lakes on changes in atmospheric depositions.  相似文献   
705.
/ The Galilee region on the northern edge of Israel constitutes more than 15% of the state's territory, supplies more than half of its drinking water needs, and is an important recreational resource and destination for Israelis. One of the main objectives of the plan for the Galilee was to devise a regional physical and economic development strategy for the years 1992-2007 that would arrest the trend of emigration of its residents, attract newly arrived immigrants to the region, and at the same time protect natural resources and environmental quality. This paper is limited to discussion of the environmental aspects of the plan. It analyzes spatial concepts for distribution of projected population growth, evaluates environmental impacts of alternative plans, and proposes a decision-making framework and tools for minimizing natural resources loss from development at the local level. Assessment of potential environmental impacts generated quantitative data of natural resources areas. Application of the data in the plan evaluation stage showed that the alternative that concentrated most of the new development in central Galilee was the second-best choice environmentally, but was preferred as the best choice for overall qualities. The planning study offers an alternative environmental impact assessment (EIA) process to the one presently used in Israel by incorporating environmental considerations at the initial plan-making stage and not at the plan-approval stage. It demonstrated that in order to be effective, environmental assessment and land-use planning should be seen as one effort that is integrated from the start and in each stage of the plan-making process.KEY WORDS: Environmental assessment; Development planning; Galilee  相似文献   
706.
Car manufacturers must eliminate automotive shredder residues (ASR). Two ways of incineration are of interest: at 850°C in municipal waste incinerators or at higher temperatures, above 1100°C in cement plants. These processes reduce the mass and the volume of waste to be disposed of in landfills and energy recovery might be possible. Regulations govern the emission of gaseous effluents to control environmental risk. To determine gaseous effluents from a pilot sacle or an industrial incineration plant, an artificial ASR was made by mixing three representative organic polymers present in the real ASR, namely polyvinylchloride, polyurethane and rubber. This mixture was incinerated at 850 and 1100°C in laboratory experiments and the analyses of the principal gaseous effluents such as carbon oxides, nitrogen oxides, volatile organic compounds, hydrochloric and hydrocyanic acids and sulphur compounds are presented and discussed. Lastly, in order to simulate artificial ASR behaviour, the composition of the combustion gases at equilibrium was calculated using a Gibbs energy minimisation code.  相似文献   
707.
Agricultural economics has, until the 1990s, enjoyeda reputation for relevance and usefulness to theagri-food industry and policy-makers. Thatreputation has been jeopardized by a growinginfatuation with models and quantification, and aconcomitant underemphasis placed on many complexproblems and issues of society. An illustrativeexample is explored, using agriculturalactivity-related damage to the natural resourcebase, environment and ecology. Agriculturaleconomists are urged to respond by broadening theirterms of reference and joining forces with otherdisciplines.  相似文献   
708.
Groundwater was being remediated with pump and treat technology at a facility where the groundwater was contaminated with commonly used degreaser solvents. Hydraulic conductivity of the heterogeneous residuum was beneficiated by applying pneumatic fracturing technology. The remedial system was controlled and monitored by a sophisticated remote telemetry system. A case history follows.  相似文献   
709.
The South Florida Water Management District (SFWMD) constructed a wetland south of Lake Okeechobee to begin the process of removing nutrients (especially phosphorus) from agricultural stormwater runoff entering the Everglades. The project, called the Everglades Nutrient Removal (ENR) project, is a prototype for larger, similarly constructed wetlands that the SFWMD will build as part of the Everglades restoration program. This innovative project is believed to be one of the largest agricultural stormwater cleanup projects in the United States, if not in the world. This publication describes the ENR project's design, construction, and proposed operation, as well as the proposed research program to be implemented over the next few years.  相似文献   
710.
For about 50 years the desertion of areas by traditional activities has led to an important evolution of landscapes and environments on the island of Ouessant. The study of this evolution has been undertaken at different spatial and temporal scales. On one part of the island, a scientific investigation carried out at the scale of the parcel enabled the form of the landscape in 1850 to be compared with that of 1985. On the whole island, the evolution of spatial organization and land use was compared between 1950 and 1985. For each of three main ecological environments, vegetational successions after the decrease of agriculture have been studied along with their future potential changes. This work highlights some considerations about the present management of the environment in relation to the major objectives of island environmental policies.  相似文献   
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