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991.
ABSTRACT: Findings of a national survey of the Corps of Engineers construction work force are presented. The purpose of the survey was to obtain information about the construction work force for use in estimating the demand on local community services associated with building Corps projects. Information on numbers of workers and dependents in-migrating to construction sites, the residential location preferences and commuting patterns of this group, and the intentions of this group to remain in local areas after project construction is presented in this paper. An example showing how this information can be used in a community service impact assessment is provided.  相似文献   
992.
A three-tiered structure of land-use and environmental management is here proposed for Australia. The structure is based on the idea that environment means the environment of people, and that environmental problems arise when a change in the interaction between people and their environment leads to conflicts about the use of land and resources. The heterogeneity of society means that a range of human aspirations and value systems must be satisfied by environmental managers. Existing methods of environmental management fail to achieve these objectives, due to inadequate perception of environmental problems by decision-makers, and the inability of currently available impact assessment techniques to resolve human conflicts associated with the use of land and resources. The main work of planning and managing land use and the environment would be carried out by regional authorities, supported by federal and state policy. Examples are given of moves towards regional administration in England and Wales, Western Australia, Australia and New Zealand. Community participation in the decision-making process is essential and can be achieved by electoral representation to the authoritative bodies and through procedures that ensure informed public comment on planning proposals.  相似文献   
993.
A Delphi survey, the Dade Toxics Community Assessment, was used to develop a consensus between citizen and professional members of the Dade TOXICS Task Force, as a part of a public participation project in Dade County, Florida. The results showed an agreement between the two groups on the ranking of the five major problems to be studied by the task force.  相似文献   
994.
ABSTRACT Both because of its effectiveness and ease in use, linear programming has become progressively popular in water resources planning problems. Yet, the assumptions of linear construction costs can be misleading. Diseconomies of scale in construction can be handled by successive approximations to the cost function but problems with economies of scale yield paradoxical results when piecewise approximations are used. If significant economies of scale exist in only one facility, the solution to problems of this nature can be found using normal linear programming codes by successively adjusting the unit construction cost on that single facility to iteratively work toward the true optimal solution.  相似文献   
995.
The communities of intestinal helminths found in the winter sample of ide (December–May, 45 fish) and in the summer sample (August–September, 42 fish) were compared. They consisted of 10 and 11 species, respectively, with Sphaerostomum globiporum being dominant in both communities. The species Parasymphylodora markewitschi and Capillaria tomentosa were found only in the summer community. Dominance and diversity (the Simpson and Brillouin indices) in the winter community were higher. All helminth species in the intestinal community of ide were of broad specificity. Therefore, host specialization does not play an important role in the forming of intestinal helminth community in this fish species.  相似文献   
996.
超大规模工业厂越来越多地应用于工业生产,但与我国现行防火技术规范存在突出的矛盾,有些地方甚至突破了我国现行防火技术规范。本文即对这一矛盾进行典型事例分析,并研究上应的安全措施。  相似文献   
997.
Problems of using food chain support as a functional attribute of a wetland are discussed. It is suggested that primary production may not be the metric that best evaluates food chain support. Environmental constructs of the wetland and resultant habitat variables appear to yield more information on life-support functions. A landscape-oriented approach is derived to separate hierarchically the wet-lands into ecological regions and landscape elements. This classification scheme allows for predetermination of environmental constraints and the possible natural limits of wetland food chain support. It is proposed that models derived from spatial location theory be used to determine the movement of animals from wetland patches experiencing impacts on food chain support. Patch size, distance between patches, habitat diversity, and environmental constraints are incorporated in these models.  相似文献   
998.
Community-based ecosystem monitoring activities in Canada are increasing in response to a number of factors including: (i) the needs of decision-makers for timely information on local environmental changes; (ii) limited use of government monitoring data and information by decision makers; (iii) government cuts to monitoring programs; (iv) the increasingly recognized need to include stakeholders in planning and management processes; and (v) the desire of citizens to contribute to environmental protection. To date there has been no network coordination of community based monitoring in Canada. This paper reports on the establishment of the Canadian Community Monitoring Network by Environment Canada's Ecological Monitoring and Assessment Network Coordinating Office and the Canadian Nature Federation. Information on research prepared in support of network establishment is presented along with a discussion of the potential of the network.  相似文献   
999.
The simultaneous behaviour of seven ecological indices(Hurlberts, Margalefs, Menhinicks, Shannons,species number, Jaccards and saprobic index) wasstudied based on phytoplankton data close to the shoreon the East coast of Sweden during the summer 1998.The sampling stations had a similar eutrophicationlevel and were located in bays. Standard phytoplanktondatabases were used in calculating the indices, whichwere later compared using cluster analysis.Hurlberts, Margalefs, Menhinicks, Shannons andspecies number indices, as measure of communitydiversity, produced similar trends which oftendiffered from those based on Jaccards index ofsimilarity. However, the simultaneous use of theseindices was found meaningful as a possible part of themonitoring close to the shore. The application of asaprobic index lead to erroneous conclusions in thestudied case.  相似文献   
1000.
Combating desertification requires the involvement of many people ranging from communities who experience the effects on a daily basis and scientists attempting to understand the biophysical and socio-economic causes and consequences of desertification, to developers and policy makers on all levels. In many instances, however, the understanding, approaches and actions of these different groups contradict rather than support one another. Over the period 2000 to 2002, a conference process undertaken in southern Africa brought together communities, scientists, and development workers to test the concept that they could connect and work together to combat desertification, given an appropriate framework. The conference was a success, and communities, scientists and developers did exchange experience, knowledge and information. Many lessons were learned, although some pitfalls were experienced. Time, funding, enhanced communication, and good will are the primary ingredients for ensuring that different sectors complement one another in their efforts to combat desertification.  相似文献   
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