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811.
Icko Iben 《Journal of the American Water Resources Association》1969,5(2):51-58
The ages-old and ever-growing need for communication and information retrieval among scientists has found expression in the development of indexes, abstracts, reviews and combinations or variations of such. A short review of such efforts is followed by a discussion of efforts along these lines in the new field of water resources science and technology. Such undertakings as the Information Retrieval System of the American Society of Civil Engineers and of the U.S. Water Resources Research Office are compared with that of the American Water Resources Association. 相似文献
812.
813.
淡水是人类赖以生存的资源,淡水的短缺已成为制约经济发展的重要因素之一,并危及人类的生存。解决淡水危机,加强淡水资源利用和管理已刻不容缓。对城市进行分流供水,对产生的废水进行分流回收处理,是实现淡水资源的持续利用,满足城市用水需要的新思路 相似文献
814.
The use of terrestrial ecoregions as a regional-scale screen for selecting representative reference sites for water quality monitoring 总被引:3,自引:0,他引:3
A process has been developed to select watersheds that are representative of terrestrial ecoregions and that are relatively
undisturbed by human activity. Using an existing land classification system at two hierarchical levels of resolution, representative
subsets (ecodistricts) of large-scale ecoregions were selected, on the basis of their physiographic, biological, and climatological
attributes, to represent the ecoregions. This was achieved using a frequency distribution analysis of existing attribute data
and choosing the ecodistrict most closely resembling the most common set of conditions for that ecoregion. Within each ecodistrict,
river basins were selected through a best-judgement evaluation of land use, coupled with an assessment of the size and location
of each river basin, in order to meet the condition of minimal human impact. Preliminary assessment of water quality data
collected from six watersheds selected in this way suggests that the process is effective in targeting regional scale river
basins exhibiting the desired characteristics. 相似文献
815.
Methods for determination of minimum pool levels in reservoirs that consider sport fishery values are being sought by managers.
We developed a technique for assessing the effects of incremental changes in minimum pool levels on potential salmonid abundance
in small (<100 surface hectares at full pool) reservoirs in Wyoming managed for irrigation and municipal water supplies. The
method has two components. One component is used to determine the minimum pool level needed to eliminate the risk of overwinter
loss of salmonids due to low dissolved oxygen concentrations. The other component predicts the potential biomass of salmonids
in reservoirs as a function of water depth and total dissolved solids concentration of the reservoir water. Application of
the method is demonstrated for two reservoirs in Wyoming.
The unit is jointly supported by the University of Wyoming, the Wyoming Game and Fish Department, and the US Fish and Wildlife
Service. 相似文献
816.
As complex social phenomena, public involvement processes are influenced by contextual factors. This study examined agency
goals for public involvement and assessed the importance of local context in remedial action planning, a community-based water
resources program aimed at the cleanup of the 42 most polluted locations in the Great Lakes Basin. Agency goals for public
involvement in remedial action plans (RAPs) were agency-oriented and focused on public acceptance of the plan, support for
implementation, and positive agency-public relations. Corresponding to these goals, citizen advisory committees were created
in 75% of the RAP sites as a primary means for public input into the planning process. Factors that influenced the implementation
of public involvement programs in remedial action planning included public orientation toward the remediation issue, local
economic conditions, the interaction of diverse interests in the process, agency and process credibility, experience of local
leadership, and jurisdictional complexity. A formative assessment of “community readiness” appeared critical to appropriate
public involvement program design. Careful program design may also include citizen education and training components, thoughtful
management of ongoing agency-public relations and conflict among disparate interests in the process, overcoming logistical
difficulties that threaten program continuity, using local expertise and communication channels, and circumventing interjurisdictional
complexities. 相似文献
817.
Kurt J. Robinson Robert M. Ragan 《Journal of the American Water Resources Association》1993,29(6):1003-1008
ABSTRACT: The reauthorization of the Clean Water Act reemphasizes the need for regional scale monitoring and management of nonpoint pollution loads. The magnitude of the task will require that local governments and their consultants integrate information systems and modeling if they are to manage the massive data sets and conduct the array of simulations that will be needed to support the decision making processes. Interfacing geographic information systems (GIS) and nonpoint pollution modeling is a logical approach. The objective of the present study was to use the 37,000-acre area defined by the Kensington Quadrangle sheet in Montgomery County, Maryland, to show that GIS-supported nonpoint pollution modeling is practical and economically attractive. The purpose of the GIS is to estimate the spatial distribution of nonpoint nitrogen, phosphorous, zinc, lead, BOD, and sediment using a model developed by the Northern Virginia Planning District Commission. The system allows the user to change land uses in subareas to simulate the consequences of additional development or alternate management strategies. The tests show that in-house development of this type of special purpose GIS is a practical alternative to vendor supplied systems and that the required databases can be developed quite reasonably. 相似文献
818.
Water samples from streams and springs in the Great Smoky Mountains National Park were analyzed for fecal coliform, fecal streptococcus, and total coliform bacteria. Levels of bacteria were found to be highly variable but related to elevation, time of year, type of water source, and water level of the streams. Visitors did not seem to be major contributors to bacterial contamination. Levels of fecal coliform and total coliform in most water samples were unsuitable for drinking without treatment. Tennessee state standards for body contact recreation (swimming and wading) were exceeded in a few samples but none from streams suitable for swimming. As a result of these findings, park managers increased efforts to inform visitors of the need to treat drinking water and removed improvements at backcountry springs which tended to give the springs the image of safe, maintained water sources. 相似文献
819.
Creg S. Bishop Glen T. Broach Wendell H. Hester Vincent A. Sikora 《Journal of the American Water Resources Association》1982,18(2):189-195
ABSTRACT: The importance of water conservation was emphasized by a proposed National Water Policy which was established during the previous Carter Administration. This policy stressed water conservation on a national scale. Such a policy sought to apply one program to all water resources problems. Before implementation of this or another such policy, consideration must be given to those vast areas of the country which in reality do not have a shortage of water. One of these areas is the French-Broad River basin in Tennessee. This report was formulated in an effort to describe both the positive and negative effects of water policies which would bring about either a 10 percent or 30 percent reduction in water usage in this basically water rich area. The parameters used in the evaluation included selected economic, sociological, legal, and environmental impacts. 相似文献
820.