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291.
292.
Gary L. Larson 《Environmental management》1980,4(2):105-110
Since the presentation of the Leopold Report (Leopold et al. 1963) to the United States Secretary of the Interior, recommendations in the document for managing natural park resources on the ecosystem level have been included in the management policies of the National Park Service. In many instances, however, management programs have continued to focus on individual resource problems, without apparent concern for the ecological consequences on ecosystems. Without knowledge of the interrelationships of ecosystem components, solving one problem may result in other resource problems. Graphic approaches are presented as potential tools to view these complex interrelationships relative to the needs of the resource manager. Interpreting the dynamics of aquatic systems is emphasized. 相似文献
293.
David M. Meko Charles W. Stockton William R. Boggess 《Journal of the American Water Resources Association》1980,16(4):594-600
ABSTRACT: Indices of annual diameter growth of trees were used to reconstruct drought in southern California back to A.D. 1700. A regional Palmer Drought Index served as predictand and tree-ring indices from eight sites as predictors in multiple linear regression analyses that yielded the prediction (reconstruction) equations. The regression explained 69 percent of the variance in Palmer Index in the period of calibration. The long-term reconstruction indicated that drought was rare in the first half of the current century relative to other discrete 50-year periods, and that based on evidence to date the last half of the 20th century may well turn out to be the most drought prone since A.D. 1700 in southern California. 相似文献
294.
Roger D. Hansen Michael F. Torpy Michael Kemp David Mills 《Journal of the American Water Resources Association》1980,16(5):862-865
ABSTRACT: The authors conducted a mail survey of 600 employers in the government and private sectors who were thought to hire water track environmental engineers. Of a total of 148 respondents, over 80 percent employed a combined total of over 2,800 environmental engineers. The survey addressed two basic questions: (1) what is the quality of graduate education recently trained engineers have received, and (2) what effect does a nonengineering undergraduate degree have on an engineering graduate student's employment potential. In answer to the first question, respondents indicated that engineering graduates were deficient in report writing, business law (contracts and specifications), economics and finance, and practical design. Many employers stated that students could better prepare themselves for employment by (1) obtaining professional experience through internships and summer or part-time jobs, and (2) learning to communicate effectively, both orally and in writing. In answer to the second question, 50 percent of the respondents indicated that engineers without an engineering undergraduate degree would not necessarily be limited in their abilities to perform engineering duties. 相似文献
295.
William B. Lord 《Journal of the American Water Resources Association》1981,17(6):1060-1065
ABSTRACT: The Water Resources Council's Principles and Standards stipulate that plans should be formulated to meet national, regional, state, and local needs or problems. It is not clear, however, how appropriate consideration can be given to both national objectives (NED and EQ) and local needs and problems. Two methods of incorporating national objectives and local problem solving into water resources planning are examined. They are plan formulation primarily in pursuit of national objectives, and plan formulation to solve local problems, but constrained by national objectives. The first of these methods is the approach which is becoming increasingly explicit in the development and elaboration of the Water Resources Council's Principles and Standards. The analysis indicates that the Water Resources Council's approach is neither the most practical nor the most desirable of the two methods examined. It creates unnecessary difficulties and fails to achieve its purpose. Plan formulation to solve local problems, but constrained by national objectives not only describes what field planners actually do, but is also more practial and more desirable. 相似文献
296.
Michael Donovan Charles A. Job William C. Sonzogni 《Journal of the American Water Resources Association》1981,17(1):23-28
ABSTRACT: The Illinois v. Milwaukee Federal District Court decision is the most far reaching application yet of the federal common law of nuisance to interstate water pollution conflicts. Although a Federal Appelate Court recently rescinded part of the district court decision, Milwaukee must still upgrade its metropolitan sewage system to a level beyond that required by federal and state regulations. The improvements must be completed with or without federal aid. The case points out the apparent inability of the Clean Water Act, the most comprehensive federal legislation affecting the nation's water quality, to deal with certain interstate water quality conflicts. The Milwaukee decision could set a precedent for similar settlements elsewhere which may in turn affect the U.S. Environmental Protection Agency's water quality clean up program. A more integrated, ecosystem conscious approach to management of shared water resources (e.g., the Great Lakes) would help reduce the need for court decisions like Illinois v. Milwaukee. 相似文献
297.
Harold E. Marshall Rosalie T. Ruegg 《Journal of the American Water Resources Association》1976,12(5):903-917
ABSTRACT: The Environmental Protection Agency administers a construction grant program to encourage abatement of wastewater pollution by sharing with municipalities the costs of wastewater treatment facilities. The enabling legislation (P.L. 92–500) specifies that EPA's cost share will be 75% of construction costs. It further requires municipalities to collect user fees from industrial users of the facilities to repay that part of the federal grant allocable to the treatment of industrial wastewater. The municipality must return half of the user fees collected to the U.S. Treasury; the municipality is allowed to retain the remaining half. Retention by municipalities of these user fees lowers their effective cost shares and results in the following consequences: (1) a bias for municipalities to select certain kinds of abatement techniques regardless of whether or not they are the least-cost techniques from the national perspective; (2) a bias for municipalities to select larger-than-optimal scales of abatement facilities; (3) a hidden federal subsidy to industry; and (4) grants that favor industrial communities. This article examines the legislative and regulatory requirements for user charges, derives the algebraic expressions for calculating the real federal, municipal, and industrial cost shares with user fees; computes municipal cost shares for selected values of the determinant factors; evaluates efficiency and other consequences of current user fee arrangements; and concludes that the efficiency distortions brought about by the impacts of user fees on cost sharing could be eliminated by requiring that all user fees collected from industry against the federal cost share be returned to the U.S. Treasury. 相似文献
298.
Leonard R. Brown 《Journal of the American Water Resources Association》1976,12(6):1181-1190
ABSTRACT: For many years, Federal water resources projects have been subjected to benefit-cost analysis to establish their economic feasibility. Several years ago social well-being was added as a consideration. This paper discusses the state-of-the-art in analyzing and evaluating aspects of social well-being. It stresses current short-falls and advocates a direction for further efforts. 相似文献
299.
Nnamdi Egbuniwe 《Journal of the American Water Resources Association》1976,12(2):393-398
ABSTRACT. The Governments of Nigeria have planned to build 395 dams in the next five years. Such water resources development may increase the incidence of Schistosomiasis, Malaria, Onchocerciasis, and Trypanosomiasis. Adequate measures should be taken to minimize adverse effects of the projects on the public health. 相似文献
300.
G. J. Kelnhofer 《Journal of the American Water Resources Association》1978,14(6):1423-1428
ABSTRACT: There are many factors, other than economic efficiency, which must be considered in judging the merits of proposed investments in the inland navigation system. No satisfactory formula exists for deciding the net worth of public investments in water resources projects. Such a measure would not be accepted because these investments can serve conflicting goals. Political, rather than technical, judgments are required to resolve these goal conflicts. 相似文献