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421.
422.
Melvin W. Anderson Ronald F. Giovannelli 《Journal of the American Water Resources Association》1980,16(1):93-99
ABSTRACT: A common problem encountered during regional planning and development of ground water dependent communities is the difficulty in deciding which areas should be preserved for aquifer recharge purposes. This paper describes the development and application of a digital overlay technique for objective evaluation and ranking of potential infiltration and potential recharge areas. Equations are developed which relate the hydrologic parameters pertaining to infiltration and recharge in a surface aquifer-confined aquifer system. These equations make use of discrete data, yet by application in a digital overlay technique results are obtained in the form of spatial distributions in order for regional trends and conditions to be examined. An application of this procedure to the 551,000 acre region of central Florida, known as the Green Swamp, is discussed. The results are presented in the form of computer generated maps which identify and rank areas of potential recharge to the aquifer system. 相似文献
423.
Ronald A. Chadderton Arthur C. Miller 《Journal of the American Water Resources Association》1980,16(2):235-242
ABSTRACT: Results of studies which have considered the relative merit of various friction slope averaging equations previously used in water surface profile computations are described. Limitations of the most accurate equation known for the M2 profile have indicated that a new equation which gives more emphasis to the upstream energy gradient is desirable. Based upon friction slope curves developed for M2 water surface profiles two new equations, one a parabolic and the other an elliptical approximation, are presented. The behavior of the new equations and of the previously most recommended equation is described by test calculations. The elliptical equation performed more satisfactorily than the harmonic method commonly recommended for M2 profile computations. Insertion of an additional cross-section about 50 feet upstream from a critical depth section was found to reduce computational errors for any energy gradient averaging method. 相似文献
424.
Jackie Sellers Ronald M. North 《Journal of the American Water Resources Association》1979,15(1):189-197
ABSTRACT: In this article a managerial approach to developing and implementing National Water Resources policy is suggested. Proper consideration can be given to national economic development (NED), environmental quality (EQ) and conservation and still result in an implementable policy at the operational level if proper incentives are built into the process with proper attention to alternate non-Federal cost sharing rates. Not only can these multiple objectives be entertained but the Administration and Congress will have a management tool that should ensure a certain probability of success. 相似文献
425.
Ronald C. Flemal Donovan C. Wilkin Ben B. Ewing 《Journal of the American Water Resources Association》1979,15(4):996-1003
ABSTRACT: A great deal of information can be derived from study of standard stream monitoring data, if these are properly ordered and organized. This information may then be used to make decisions about water quality management. Among critical information items are evaluation of performance to standards, determination of seasonality and time-trends of water quality conditions, and estimation of the effects on water quality to be expected from load reductions or standards modifications. Additional information on the magnitude of individual pollution sources is also critical to water quality management. Each of these items can be derived within the water quality information system which is currently under development for the State of Illinois. 相似文献
426.
Jayson K. Harper Ronald C. Griffin 《Journal of the American Water Resources Association》1988,24(6):1317-1327
ABSTRACT: Texas river authorities are a type of large, regional water district that must be financially self-sufficient. An institutional and historical study of Texas river authorities reveals the broad power of these organizations and their influence in water management. River authorities now control 25 percent of surface water deliveries in Texas. Over two-thirds of authority water was developed by river authorities; nearly one-third was purchased from private or public ventures. While river authority activities have been effective where these services are marketable, the provision of public good services is limited. Increased visibility of these organizations is paralleled by challenges to their traditional autonomy. 相似文献
427.
Ronald J. Deluga 《组织行为杂志》1988,9(4):359-366
The purpose of the present research was to investigate the political nature of leadership by examining the association of the task-people leadership approach with strategies used by subordinates to influence their superiors. Forty-eight faculty members (31 males and 17 females) from a school of higher education completed the T-P Leadership Questionnaire and Profile of Organizational Influence Strategies. Reponses were analyzed using Pearson product-moment correlations. The results indicated that as perceived task-centered leadership increased, employees reported a significantly greater use of bargaining, assertiveness, higher authority, and coalition as strategies to influence their superiors. The relationships were observed only during second influence attempts. Further, it was observed that as the perceived level of people-centered leadership behavior rose, subordinates reported a significantly decreased use of bargaining and higher authority as influence strategies during first influence attempts. The findings are discussed in terms of the reciprocal and political character of managerial- subordinate relationships. 相似文献
428.
The Shechter-Lucas wilderness use simulation model (WUSM) has been modified to quantify the effects of fluctuating Glen Canyon Dam releases on Grand Canyon river trips. The model now simulates changes in flow as predicted by the Streamflow Synthesis and Reservoir Regulation computer model for the Colorado River. This revised WUSM provides data on several flow-related effects, including delays at rapids, encounters with other parties, and the time available for visiting attraction sites. Nine flow alternatives are evaluated and compared. Analysis of these outputs provides useful information to the Bureau of Reclamation on how the operation of Glen Canyon Dam effects river trips through Grand Canyon National Park. 相似文献
429.
Ronald C. Griffin Bruce A. McCarl 《Journal of the American Water Resources Association》1989,25(1):175-186
ABSTRACT: Policies to encourage brush management are under consideration as a means to address the water scarcity issue in Texas. Additional water can be generated by treating some of the 100-million-plus acres of brush-infested rangelands in Texas. Evidence of water yield benefits are, however, tentative at this time. Economic investigations based on available data show the potential desirability of brush management but also show benefits to be critically dependent on added water yield, value, and cost-sharing policy. Wildlife, water rights, and environmental issues are also important considerations. The lack of research information on likely impacts makes it difficult to choose among alternative policies for encouraging brush management. More research on this potential opportunity is needed. 相似文献
430.