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71.
Applications of in situ agrobiodiversity conservation practices within agricultural production systems have the potential to reduce the risks of agricultural modernisation and enhance sustainable development. The aims and approaches for in situ conservation differ according to the requirements of communities and nations. Approaches to in situ conservation in the decade after the Convention of Biological Diversity are reviewed within the contexts of marginal agricultural systems in Nepal, Turkey and Switzerland. Numerous approaches are currently utilised, including: the informal de facto retention of agrobiodiversity; the provision of state assistance; the marketing of agrobiodiversity products; the use of technological innovations to develop local diversity; the establishment of conservation reserves; community assistance programmes and the raising of awareness of the issue amongst all sectors of societies. Emerging complementary in situ approaches applicable in the rural margins suggest a framework for effectively conserving agrobiodiversity by working with local people.  相似文献   
72.
The environmental impact of loss of natural stream and riparian habitat is of concern throughout the United States and Europe. Environmental impacts related to such activities as channelization of and levee construction along streams and rivers are particularly apparent in the Midwestern United States. The objective of the research presented here was to delineate the extent, relative degree of impact, and implications for management of channelization and levee construction along watercourses located in the state of Illinois. According to records maintained through the Illinois Streams Information System data base (Illinois Department of Conservation), nearly 25% of surface water resources in the state have been modified directly by channelization and/or levee construction. Reviews of agency records, elaboration of case histories, interviews with agency personnel, and inspections of impacted sites indicated that these alterations have occurred without the benefit of effective mitigation. Although permit records may provide suggestions for mitigation to be incorporated in the design of a particular project, permits issued generally do not require even minimal instream habitat and bank stabilization efforts in conjunction with channel alteration. Information derived from policy and case study analyses suggests that institutional constraints, rather than lack of particular understanding about mitigation, provide major barriers to protecting the state's surface water resources in terms of regulatory review, policy interpretation and implementation, and project evaluation. Recommendations for environmental management efforts regarding these and similar channel alterations are elaborated from these findings.  相似文献   
73.
The traditional approach to water resources management for urban areas has been based on the examination of needs and the design of separate facilities for water supply, drainage, and waste water collection and treatment. The complexity and interaction among the separate systems required by a metropolitan area has complicated their management and promoted research interest in developing a methodology for better coordination. However, a more thorough evaluation of the problem reveals the real research need to be both more complicated and different in character than the problem in systems analysis suggested by the first superficial glance. Water management relates to the much broader problem of community design; when, where, and in what manner should new urban development take place. Furthermore, the character and needs of areas within the metropolis are constantly changing. The key distinctiveness of urban water management is the imperative for design and operation flexibility. The key research need is to develop new designs, operation procedures, and institutional arrangements to make the flexibility demanded by a dynamic urban community possible.  相似文献   
74.
Biological plugs are an innovative, low-intervention, in-situ bioremediation methodology for both saturated and unsaturated contaminated soils. They are modular in-ground immobilized microbe bioreactors designed to rapidly increase the oxidation of organic contaminants by placing an adapted consortia of microorganisms in close proximity to the contaminants of concern. The approach is versatile, in that contaminants can be remediated in-situ without the removal of existing structures as well as being able to efficiently and economically treat contaminants over a large area. Amine- and glycol-contaminated soils at gas sweetening plants, represent a significant problem in magnitude, prevalence, and risk along pipelines stretching through Canada's western provinces. A field pilot study was conducted at an isolated former gas sweetening plant in northwestern Alberta. Monoethyamine (MEA) and several glycols were successfully remediated in situ in a 138-day time frame. Soil toxicity was significantly reduced. The engineering challenges and associated economics of remediating such isolated sites are also presented.  相似文献   
75.
Odors emananting from animal production facilities are the primary environmental cause for complaint resulting in great corrective expense and, in many instances, facility closure. The current state-of-the-art of odor control technology ranges from intensive waste management and good housekeeping practices to chemical treatment and facility isolation. These controls at best only limit the generation and/or quality of animal production odors. The most effective odor limiting technologies are the most cost intensive. Therefore, methods used are dependent upon the seriousness of the situation and the cost-benefit that may be derived from their use.Original facility design and site selection consideration are of great importance to the existence of confined animal feeding enterprises with a non-farm population which is encroaching at increasing rates into rural areas. Land use planning and zoning restrictions for agricultural/animal feeding purposes may well be the ultimate odor control tool of the future for newly instituted facilities. Extensive basic and applied research is required to provide adequate technology for use by existing facilities.  相似文献   
76.
This paper aims to present an assessment of the environmental radiological exposure at a Brazilian area of high natural radiation and discusses the indoor radon exposure risk. A survey of inhabitant exposures arising from the inhalation of radon progeny and external gamma exposure was conducted in urban and rural areas of the Po?os de Caldas Plateau, which is recognized worldwide as a high natural radiation region. The results of this survey indicated that highest radiation exposure was restricted to the rural area of Po?os de Caldas. The radiation exposure in urban locations was quite similar to the values observed in normal background areas in some Brazilian counties. By the application of a constant relative risk model, an additional 20% in the lifetime risk of lung cancer mortality due to the exposure to radon progeny was estimated at Po?os de Caldas. It was also estimated that 16% of all lung cancer deaths at Po?os de Caldas county could be attributable to radon exposure.  相似文献   
77.
Exposure of workers in mineral processing industries in Brazil   总被引:2,自引:0,他引:2  
The mining, milling and processing of uranium and thorium bearing minerals may result in radiation doses to workers. A preliminary survey pilot program, that included six mines in Brazil (two coal mines, one niobium mine, one nickel mine, one gold mine and one phosphate mine), was launched in order to determine the need to control the radioactive exposure of the mine-workers. Our survey consisted of the collection and analysis of urine samples, complemented by feces and air samples. The concentrations of uranium, thorium and polonium were measured in these samples and compared to background data from family members of the workers living in the same dwelling and from residents from the general population of Rio de Janeiro. The results from the coal mines indicated that the inhalation of radon progeny may be a source of occupational exposure. The workers from the nickel, gold and phosphate mines that were visited do not require a program to control internal radiological doses. The niobium mine results showed that in some areas of the industry exposure to thorium and uranium might occur.  相似文献   
78.
Many empirical environmental justice (EJ) studies lack a systematic framework in which to undertake research and interpret results. This paper characterizes the conventional EJ study and examines how results can be influenced by the choice of the spatial scale and scope of analysis. After thoroughly reviewing a sample of prominent EJ studies, a conventional EJ study was performed for (Superfund) National Priorities List sites at multiple scales and scopes. It was found that evidence of environmental injustice could be sensitive to scale and scope chosen, which partly explains the observed inconsistency in the empirical literature. Implications for interpreting existing EJ research and conducting future EJ research are discussed.  相似文献   
79.
80.
ABSTRACT This paper describes the development and use of a mixed integer programming model for the planning of land disposal wastewater treatment facilities. Consideration is given to relevant construction and operating costs for land sites, transmission arteries, land acquisition costs, tangible benefits from land use, controls on aquifers, and various other engineering and technical constraints The model is used to determine which land disposal sites should serve which treatment plants, when initial construction should be initiated and completed, and when capacity expansion should occur. The model's application to the St. Louis Standard Metropolitan Statistical Area is illustrated and discussed.  相似文献   
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