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931.
Robert H. Becker 《Journal of the American Water Resources Association》1981,17(4):623-626
: The National Wild and Scenic River Act of 1968 was designed to protect the nation's unique waterways. This Act, however, has been criticized for negatively affecting areas it was intended to protect. Findings, based on field investigation in the Upper Mississippi River basin suggest that designation may serve as a factor for increasing recreational use levels on the protected rivers. This study discusses the social and recreational consequences of designating rivers and the attitudes of river users regarding designation. 相似文献
932.
Dennis W. Callaghan Sara S. Callaghan Robert A. Comerford 《Environmental management》1977,1(3):227-234
Given the ecological burden imposed by power plants located in the coastal zone, efforts to improve the marginal benefits realized from their operation are warranted. Indeed, if this source of environmental pollution can be utilized to compensate for past ecological damage, then the benefits will be magnified many-fold.This study addresses the economic feasibility of utilizing heated effluent water from power plants to invigorate the growth of oysters raised under controlled conditions. The preliminary findings indicate that given proper combinations of system capacity, supplemental nutrient supplies, sea water flow and temperature gradients, such an operation is feasible.This is also a demonstration of a viable application of a sophisticated computer modeling approach to environmental problems. System Dynamics a technique pioneered at the Massachusetts Institute of Technology, is applied to evaluate the physical, biological, and economic interrelationships of the aquacultural system variables. It offers many advantages for the environmental manager and researcher, a number of which are realized in the present investigation. 相似文献
933.
We are often tempted to believe that a nation's resource policy is the result of careful deliberation and conscious design and is articulated in a relatively few statutes. This paper traces the history of percentage depletion in the USA and finds that this particular resource policy has evolved in the absence of a recognizable master plan. Percentage depletion has developed through a continuing political tug-of-war in the US Congress as a seemingly unending array of special interest groups sought and finally gained the prize of percentage depletion for their industry. 相似文献
934.
Robert Dyer 《Journal of the American Water Resources Association》1977,13(5):1069-1081
ABSTRACT: H2SO4 (sulfuric acid) is formed by a chemical process that occurs in unreclaimed coal mines. The highly toxic acid then flows into the lower swamp areas where it causes considerable damage to the ecosystem. The major effect of the acid is the mass destruction of thousands of trees and various other phreatophytic plants. The contamination is so serious that most of the wildlife has migrated out of the affected area of the swamp in order to survive. Certain geological features such as coal bearing monadanocks make the area somewhat sensitive to mining activities and related geologic hazards. New methods of mine acid abatement make the concept of mass reclamation more realistic than at any time in the past. The constant annihilation of swamp life and processes emphasizes the urgent need for reclamation of the swamp. 相似文献
935.
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
936.
Rand E. Eads Robert B. Thomas 《Journal of the American Water Resources Association》1983,19(2):289-292
ABSTRACT: A depth proportional intake boom for portable pumping samplers was used to collect suspended sediment samples in two coastal streams for three winters. The boom pivots on the stream bed while a float on the downstream end allows debris to depress the boom and pass without becoming trapped. This equipment modifies point sampling by maintaining the intake nozzle at the same proportion of water depth regardless of stage. Data taken by pumping samplers with intakes mounted on the boom were compared with depth integrated hand samples. Pumped samples showed higher concentrations than depth integrated hand samples. Results suggested that cross-sectional sampling can give high precision with proper placement and calibration of a boom mounted intake. 相似文献
937.
938.
Robert T. Lackey 《Environmental management》1979,3(2):109-112
Conclusion As a final thought, I want to conclude with the cliche that a problem recognized is half solved. Certainly, I cannot be accused of laying out a solution to solving the major fisheries management problems, but it is hoped that the problems managers face are now clearer. The complexity of fisheries assystems to be managed is clear to even the most casual observer. The second point, a broad theory of fisheries management, should provide a framework to categorize all of the disjointed activities that we associate with management of our fisheries resources. 相似文献
939.
Robert C. Ward 《Journal of the American Water Resources Association》1979,15(2):369-380
ABSTRACT: Regulatory water quality monitoring has evolved to the point where it is a rather complex system encompassing many monitoring purposes and involving many monitoring activities. Lack of a system's perspective of regulatory monitoring hinders the development of effective and efficient monitoring programs to support water quality management. In this paper the regulatory water quality monitoring system is examined in a total systems context. The purposes of regulatory monitoring are reviewed and categorized according to their legal evolution. The activities of regulatory monitoring are categorized and organized into a system which follows the flow of information through the monitoring program. The monitoring purposes and activities are combined to form a monitoring system matrix - a framework within which the total regulatory water quality monitoring system is defined. The matrix, by defining the regulatory monitoring system and clarifying many interactions within the system, provides a basis upon which a more thorough approach to managing, evaluating, and eventually optimizing regulatory monitoring can be developed. 相似文献
940.
Robert R. Lansford Shaul Ben-David Fred Roach Bobby J. Creel Thomas H. Stevens Raymond J. Supalla Lynn Gelhar William D. Gorman Richard W. Mead Donald B. Wilson 《Journal of the American Water Resources Association》1979,15(6):1589-1601
ABSTRACT: The economic feasibility of a large scale dual purpose (desalting water and power production) facility were evaluated. Although a site in the Tularosa basin of southern New Mexico was chosen as a case study for this analysis, it is believed that the approach and consequential results would be applicable to alternative sites in the Southwest. The basic project evaluated included: a) a ground water well field; b) a dual purpose, nuclear, desalination plant; c) a mineral recovery plant; and d) a reservoir for recreation and irrigation storage. Principle project outputs included electrical power, minerals, recreation, and water for either irrigated agricultural production or export to an adjoining river basin. Two alternative project designs were developed for detailed analysis. The first alternative encompassed all major project components. The results, in discounted net values used to assess the feasibility of the project, were essentially negative; that is, values were less than zero for full scale development. The net benefits ranged from $-986.57 million at a 5 percent discount rate, to $-1,137.528 million at a discount rate of 10 percent. In the second alternative, exportation of the desalted water from the Tularosa basin to two adjacent rivers was analyzed with somewhat better net benefits, ranging from $-382,527 million to $-478,612 million at the 5 and 10 percent discount rates. 相似文献