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931.
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   
932.
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   
933.
ABSTRACT: The Monte Carlo method is a procedure which takes advantage of the high speed of electronic computer in solving complex problems in physical and mathematical fields. A rigid technique to determine whether a random point falls within an arbitrary-shaped boundary is not available. This study is to present a new technique which can be used to determine whether a random point falls within any shape of boundary, together with its range of application. A modified fixed random walk procedure is also developed to solve the problems of groundwater movement. A flowchart and computer program are also demonstrated. Comparisons of this newly developed method are made with other approximate solutions. The results indicates that the new technique is more applicable and powerful than other methods.  相似文献   
934.
ABSTRACT The growing social consciousness and concern with human well-being has resulted in numerous water resource use and control programs, the results of which must be measured not in the customary monetary terms, but rather in terms of social and human welfare. Interdisciplinary research offers the greatest promise of yielding fruitful results in establishing planning methodology that would result in a maximum utilization of funds available for water resource programs. Working with the various social science disciplines, accountants have begun research in social measurement thus opening the door to a new field of accountancy known as socio-economic accounting. The development of social accounting systems will improve water resource management by projecting heretofore unmeasureable social values into the management decision making process.  相似文献   
935.
Decisions to develop water resources systems so far have been primarily taken on the basis of engineering and economic feasibilities. Very rarely, if ever, sociological feasibility has been considered, except in a very broad sense. Planning is for the people, and it should improve the quality of life. Hence, it is argued that water resources decisions ought to be primarily social ones, and that the success or failure of any resource development should not only be judged by its techno-economic excellence but also by its impact on people. Water resources planning process is discussed, and the difficulties associated with the evaluation of sociological feasibility of projects are enumerated. The social consequences of water development projects are traced through planning, construction, operation and management impacts. Finally, it is suggested that the foremost factor in the success of any water management program is the public understanding and acceptance of that program.  相似文献   
936.
937.
Environmental regulation of industrial activity is generally believed to have a negative impact on the industry. Recent literature has suggested, however, that reducing industrial waste outputs can, in some circumstances, result in a 'win-win', or at least 'win-draw', scenario for industry and the environment. The viability of using the abatement cost curve method as a management tool to enable the achievement of a 'win-win' state is investigated here. Copper pollution in the Humber Estuary is used as a case-study, and the abatement cost curve methodology proves to be a valuable tool in identifying barriers to achieving the win-win state, and also in providing future direction for the waste management strategy. Abatement cost curves are concluded to be powerful management tools which greatly improve the transparency of waste reduction information.  相似文献   
938.
Agricultural lands have the potential to contribute to greenhouse gas mitigation by sequestering organic carbon within the soil. Credible and consistent estimates will be necessary to design programs and policies to encourage management practices that increase carbon sequestration. Because a nationwide survey of soil carbon by the wide range of natural resources and management conditions of the United States is prohibitively expensive, a simulation modeling approach must be used. The National Nutrient Loss Database (NNLD) is a modeling and database system designed and built jointly by the USDA– Natural Resources Conservation Service (NRCS) and Texas A&M University to provide science-based inferences on environmental impacts from changes in agricultural management practices and programs at the regional and national level. Currently, the NNLD simulates 16 crops and covers 1.35 × 108 ha. For estimating soil carbon sequestration, the database will be populated with 1.5 × 106 field-level model runs using the EPIC (Environmental Policy Impact Calculator) model, which includes newly incorporated carbon equations consistent with those in the Century model. Each run will represent a unique situation defined by state, crop, climate, soil, irrigation type, conservation practice, tillage system, and nutrient management treatment (nutrient rate, application frequency, application timing, and manure category). Results are to be assigned to specific National Resource Inventory points (NRI) to simulate regional and national baselines. In this article we present the modeling approach and discuss the strengths and limitations. Published online  相似文献   
939.
Natural Resource Management to Offset Greenhouse Gas Emissions   总被引:1,自引:0,他引:1  
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940.
There have been no published performance evaluations of nongovernmental, voluntary habitat stewardship programs. The Operation Burrowing Owl (OBO) stewardship program, initiated in 1987, was evaluated for its effectiveness in conservation of grassland habitat during 1986–1993. The 108 OBO sites from 1987 to 88 and 98 randomly selected non-OBO sites that were grassland in 1986 in the Regina-Weyburn, Saskatchewan study area were classified by size and agricultural soil suitability. By 1993, 41 (38%) of the 108 OBO sites had been withdrawn from the program. The 1986 area of grassland was compared with grassland area calculated from digitized 1993 LANDSAT imagery. A correction for satellite inaccuracies was determined. Grassland retention in 1993 was significantly higher at OBO sites (66%) than at random sites (49%), demonstrating that the OBO voluntary program effectively conserved habitat. Also, grassland retention was significantly lower on sites with better agricultural soils, and for sites <12 ha in size. Site type (OBO or random), size and their interaction, followed by agricultural soil suitability, had the greatest effects on grassland retention. During an era of accelerated grassland loss, OBO strongly and positively (statistically significant) affected conservation of grassland sites most at risk: sites <12 ha in size and with good to excellent agricultural soils. This suggests that grassland conservation efforts focus on vulnerable sites (small size and/or good agricultural soils) to provide nesting habitat for burrowing owls. Our study demonstrates that a voluntary stewardship program can significantly increase conservation of habitat.  相似文献   
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