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451.
Donald B. K. English J. M. Bowker 《Journal of the American Water Resources Association》1996,32(6):1319-1328
ABSTRACT: This paper presents estimates of the statewide economic impacts of guided whitewater rafting on five rivers in six states: the Nantahala (North Carolina), Gauley (West Virginia), Kennebec (Maine), Middle Fork of the Salmon (Idaho), and Chattooga (Georgia-South Carolina). Except for the Chattooga and Middle Fork, rafting is dependent on upstream dam releases. Guide fees range from about $15 per trip on the Nantahala to over $1,000 on the Middle Fork. Economic impacts per nonresident 1000 visitors increase along with length of the rafting trip and remoteness of the river. Total industrial output per 1000 nonresident visitors ranged from $95,000 on the Nantahala to over $2.5 million on the Middle Fork. However, because of differences in annual visitation levels, total impacts were greatest at the Nantahala, at over $14 million in 1993. Multipliers for all economic measures were relatively consistent over the rivers. Employment multipliers (Type III) ranged from 1.67 to 1.90, income multipliers from 2.0 to 2.4, and industrial output multipliers from 2.1 to 2.5. 相似文献
452.
葛曰刚 《中国环境管理干部学院学报》1999,(4)
环境保护与经济建设协调发展是实施可持续发展的重要环节。为使环境保护与经济建设协调发展,必须在发展社会经济中,建立并不断完善经济建设与环境保护综合决策机制。 相似文献
453.
Sarah Kandrot Val Cummins Declan Jordan Jimmy Murphy 《International Journal of Green Energy》2020,17(11):687-696
ABSTRACT The imminent development of a number of offshore wind farms in the Republic of Ireland presents a sizable opportunity to stimulate the Irish economy through the growth of an indigenous and globally competitive offshore wind supply chain. This study uses a value chain analysis to evaluate the economic and employment potential of the offshore wind sector for Ireland. The analysis is based on the expenditure on products and services required to develop an offshore wind farm, the planned capacity of projects in the pipeline, and the ability of Irish companies to supply the sector. Results suggest that by 2030, 2.5–4.5GW of domestic offshore wind development could create between 11,424 and 20,563 supply chain jobs and generate between €763 m and €1.4bn in gross value added. This is the first study to estimate domestic GVA potential for the sector. 相似文献
454.
James W. McFarland M. Leon Hyatt 《Journal of the American Water Resources Association》1973,9(4):755-767
Alternative futures are defined to be mutually consistent alternative combinations of assumed sets of future conditions. Alternative futures are employed in conjunction with the Wollman-Bonem model to project future water use. The model solutions under different alternative futures provide an indication of the direction and relative magnitude of changes in water use, both in quantity and quality, that may result from changes in policy-influenced variables, technology, and other data. The Wollman-Bonem model is employed in this paper as a tool to illustrate the alternative futures concept. The model can best be cast as an economic model. The model solutions are not given as a set of formal projections, but as various possible water-use-over-time curves. This should aid in disspelling the erroneous idea that it is possible to make distant projections of water use as a single curve. Multiple curves suggest that water use is really a function of many variables. 相似文献
455.
对地震保险体制改革的探索 总被引:1,自引:2,他引:1
从研究地震灾害规律和保险经营特点之间的矛盾入手,叙述地震保险经营的困难,剖析我国现行地震保险体制的缺陷,提出了建立一个新的,相对科学和合理的地震保险体制的若干建议。 相似文献
456.
The international minerals industry continues to have a substantial investment shortfall. The widening exploration and mineral development gaps, not only in the lesser developed countries but also in the developed nations, are sowing the seeds for future mineral supply disruptions and conflicts. Mutuality of interests demands concerted initiatives, individual as well as collective, to reverse the investment trends established by international mineral finance and the multinational corporations in order to pave the way for secure mineral supplies in the future at acceptable prices. 相似文献
457.
Courtland L. Smith 《Environmental management》1980,4(1):7-11
Fishery management concepts incorporate a number of value judgements about what social goals are right for a fishery. These value judgements result in optimizing some goals over others. Since the public, fishermen, and consumers weight goals differently than managers, frustration and conflict result. The correspondence between social goals specified by the public and those inherent in management concepts needs to be evaluated. 相似文献
458.
William C. Hughes 《Journal of the American Water Resources Association》1980,16(2):267-270
ABSTRACT: Errors inherent in the conputation of water surface profiles are magnified by the shallow lateral slopes typical of most flood-plains, producing significant floodplain mapping errors. An economic optimization procedure which weighs the cost of overstating the location of a floodplain boundary against the cost of understanding the location provides a means for establishing the boundary location. In most cases the cost of overstating the boundary location exceeds the cost of understating the location by several magnitudes so that the boundary location should coincide with the minimum water surface elevation which would be expected to result from a flood of specified recurrence interval. 相似文献
459.
Lewis A. Rossman Frank T. Vanecek 《Journal of the American Water Resources Association》1978,14(4):842-855
ABSTRACT: An improved computational procedure for solving water quality management models containing interacting pollutants and control policies is presented. The method is developed with respect to the specific problem of minimizing the costs of basin-wide thermal and organic pollution control to meet water quality standards. It views the problem in partitioned form where a master problem is used to find cooling levels for thermal polluters while subproblems determine optimal organic pollutant reductions for fixed cooling levels. A gradient based search procedure is used to solve the master problem. Computational results for several river systems are presented. Application of the method to other water quality management models is suggested. 相似文献
460.
Anthony S. Donigian Ray K. Linsley 《Journal of the American Water Resources Association》1979,15(1):1-16
ABSTRACT: This paper describes a methodology for the evaluation of water quality plans analogous to procedures used in flood control planning, where flood damage frequency curves provide the basis for determining flood control benefits. The proposed method uses continuous water quality simulation to develop long term information from which water quality frequency curves can be obtained. This frequency information allows the evaluation of the impact of proposed water quality control plans taking into consideration the variable nature of the water resource. Using treatment costs and other economic indicators of water quality, the frequency information can be used to estimate the cost-effectiveness and economic efficiency of alternative plans. The method is demonstrated in a semi-hypothetical environment; real hydrologic and climatic characteristics are assigned to a hypothetical watershed configuration. Alternative management plans are simulated and analyzed for both physical and economic impacts. The advantages of continuous simulation and its use in water quality planning are explored. 相似文献