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951.
红厚壳野生资源的开发型保护途径分析 总被引:1,自引:0,他引:1
从红厚壳的生物学特性和具有的油用、药用、材用、观赏、生态保护等多种用途角度出发,针对砍伐严重的状况,提出通过驯化栽培、开发油脂应用范围和加强海岸防护林的设置来保护红厚壳;同时建议政府和科研部门重视并探索红厚壳在中药和油脂加工方面的价值。 相似文献
952.
运用不完全信息重复博弈的基本理论和分析方法,建立了地方政府与煤矿企业的多阶段动态博弈模型。不完全信息的引入改变了完全信息博弈中地方政府会随着从煤矿生产中获益越大对其提供的庇护程度越大,而企业必然选择干扰的结论。一旦地方政府的这种合作行为出现,国家在安全监察方面的成本和难度将会大大减低。 相似文献
953.
ABSTRACT. Planning an optimal system of activities for generating economic goods and services within an existing natural resource capacity is a difficult problem to solve. A mathematical programming model with the capacity to check multiple resource demand and supply compatibility over many time periods was developed for the solution to this type of problem. The characteristics of natural resource supply and the demand of activities were utilized to reduce the number of time periods and to minimize the loss of the dynamic reality of the problem. Reduction in the number of time periods extended the capability of the model to the solution of complex resource planning problems without oversimplification. 相似文献
954.
Andrew A. Dzurik 《Journal of the American Water Resources Association》1979,15(2):420-425
ABSTRACT: Methods of floodplain management are changing in the United States. There has been a gradual shift in emphasis from “flood control” to “management” of the floodplain. The complexities of multilevel governmental involvement in floodplain management demand an analysis of a new means to coordinate these efforts. It is the intent of this paper to discuss the role of the Corps of Engineers in this area and the problems the Corps has encountered in its endeavors. The occurrence of these problems indicates that there is a need to strengthen the federal role to ensure a comprehensive view of floodplain management. 相似文献
955.
James Fulton William L. Chase 《Journal of the American Water Resources Association》1979,15(2):426-435
ABSTRACT: The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the Nation for waste water reuse. Overriding all of these conditions is the long-term inadequacy of the existing water supplies. The Salt River Valley has a ground water overdraft of about 700,000 acre feet per year. To help alleviate this situation, the Corps of Engineers in conjunction with the MAG 208 is looking at ways to reuse a projected 2020 waste water flow of 340,000 acre feet per year. Reuse options identified include ground water recharge, agricultural irrigation, turf irrigation, recreational lakes, fish and wildlife habitats, and industrial cooling. These look nice on paper but before they can be implemented, some hard questions have to be answered, such as: How acceptable are local treatment plants when 15 years ago there was a major push to eliminate local plants; is the Phoenix area ready for reuse in urban areas; what are people willing to pay for water; who benefits if a city goes to ground water recharge; how much agriculture will be left in the area by 2020? These and other questions must be resolved if reuse is to become a viable option in water resource planning in the Phoenix area. Summary. Large scale reuse of waste water conforms with the national goal of better resource management through recycling. The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the nation for waste water reuse. Some of the most notable conditions are: the existence of a large and rapidly growing urban area which is in the process of planning for future waste water management systems; the existence of agricultural areas which are projected to be farmed well into the future, and the existence of constructed and planned major recreational systems such as Indian Bend Wash which can use recycled waste water; the existence of extensive depleted ground water aquifers; the need for a dependable source for the cooling of the Palo Verde Nuclear reactors; and finally, overriding all of this, the long-term inadequacy of the existing water supplies. Given this, one would expect to find total reuse within the Phoenix metropolitan area. Reuse is taking place with irrigation and nuclear power cooling to the west but there is no long term plan which looks at the Valley as a whole and considers waste water as part of the Valley's water resources. The Corps 208 plan is looking at waste water in this manner but initial analysis shows that although reuse is technically feasible there are many financial, social, institutional, and political questions still to be answered. These include: determining the value of existing diminishing water sources and what people are willing to pay for the next source of water; are people willing to identify priority uses of water for the area so that water of varying quality is put to its highest and best use; will the present institutional boundaries remain to create water-rich and water-poor areas; and will legislation be forthcoming to simplify the complex surface and ground water laws that presently exist? The Corps 208 study will not be able to answer these questions, but the goal at the moment is to identify feasible reuse systems along with decisions the public, owners, agencies, and politicians must make to select and implement them. If some sort of logical process is not developed and public awareness not increased, the chance for a long-term plan to utilize waste water as a major element in the Phoenix area water resource picture, may be missed. 相似文献
956.
Marshall Flug Wynn R. Walker Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1979,15(4):964-973
ABSTRACT: The Upper Colorado River Basin contains appreciable amounts of undeveloped fuel resources. Large quantities of oil shale, coal, and uranium have attracted recent economic and commercial interests. Development of these resources and subsequent conversion to alternative energy forms require an adequate supply of water. Water use for large scale energy development will place increasing demands on an already overstressed allocation of Colorado River water. Present water quality is at a concentration where increased salinity will result in economic detriments to holders of downstream water rights. The salt and water exchange in mining, processing, and spent fuel disposal processes has been incorporated as part of a two-level minimum cost linear programming algorithm. Mathematical simulation results provide an optimal use of Upper Colorado River water for levels of energy output such that salinity concentrations are maintained below predetermined levels. 相似文献
957.
Judith A. Pickering Richard A. Andrews 《Journal of the American Water Resources Association》1979,15(4):1039-1049
ABSTRACT: The objective of the study was to evaluate alternative land developments around New Hampshire lakes. Alternative development patterns, evaluated by their impacts on the lake area environment and area economy, included residential patterns, commercial patterns, and combinations of these two types. Phosphorus loading of the lake water was used as a proxy variable for changes in the lake water quality. Commercial developments yielded the highest revenues to the town and the local area. It also attracted the most lake users to the area as well as contributing the largest phosphorus loading in the lake waters. Residential developments, although contributing high revenues to the businessmen in the area, yielded less net income to the town. Phosphorus loading levels from residential developments were much lower than lake phosphorus loading by commercial developments. 相似文献
958.
E. Susan Boydstun Terry Nelson Roger B. Long 《Journal of the American Water Resources Association》1979,15(4):1086-1095
ABSTRACT: Public investments in water resource development projects are continually under scrutiny in terms of economic, environmental, and social impacts. Results of an analysis of a water development project that supplies irrigation water in Idaho are discussed in terms of the impact on income distribution and income growth 44 to 64 years after the project was initiated. Gini ratios for the rural farm population of these counties were consistently lower than they were for the United States as a whole and for the state of Idaho. In addition, income distributions tended to become more equitable over time in the water project counties. Rural farm population income growth rates were found to be similar to those for the nation as a whole. Some of the reasons for these results may be related to the tendency for income distribution to become more equitable as income increases, and the fact that average farm size is relatively small. 相似文献
959.
Earl C. Leatherberry 《Journal of the American Water Resources Association》1979,15(5):1281-1292
ABSTRACT: During the past 15 years a number of methods have been developed that purport to evaluate the amenity values of rivers. Most methods are designed to identify the physical, biological, cultural, and esthetic features of a river or river corridor that are conducive to recreation, preservation, and other amenity values. This paper reviews and comments on 13 methods that evaluate amenity values. The methods are reviewed and discussed under three general headings: River Recreation Potential Evaluation, River Esthetic Evaluation, and River Preservation Evaluation. A final section of the paper identifies areas where improvements and further research are needed. 相似文献
960.
William E. Hammitt 《Environmental management》1980,4(5):425-431
Bogs are of interest to outdoor recreationists, but little information exists concerning how recreation resource managers might manage these areas to enhance visitor benefits. This study evaluates bog visitor characteristics and experiences, visual preferences, and reasons for visiting. Implications for recreational resource management of bogs include the location and design of boardwalk trails and management of understory vegetation to meet the visual preferences and motives of bog visitors. 相似文献