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131.
袁兴中  刘红 《资源开发与市场》1995,11(4):162-164,173
山东省自然条件优越,生态环境多样,因而具有极其丰富的生物多样性,本文初步研究了山东省生物多样性现状,保护与经济协调发展对策。  相似文献   
132.
The concern of this paper is with the spatial consequences of development in a given rural setting and the way in which physical planning fits into the revival of a dying rural area, particularly in Third World Countries. It is based on experience derived from Dekinal in Benue State, Nigeria and endeavours to define a rural area by briefly discussing its characteristics and highlighting its problems. It proposes a comprehensive development planning process to induce development based on available resources.  相似文献   
133.
ABSTRACT: Tradeoffs between regional economic development and resource use is a question often confronting local decisionmakers. A resource-interindustry model can be used to depict the interrelationships between regional economic sectors as to household income and/or employment and resource use. A resource-interindustry model was developed for Humboldt and Lander Counties in Nevada which shows the tradeoffs between regional household income (wages, salaries, profits, and rents) and/or employment and water usage. Water income and water employment multipliers can be ranked, enabling decisionmakers to realize sectors which require greatest regional water usage to regional household income and/or employment.  相似文献   
134.
Across the globe, continued policy debates regarding the management of old-growth forests center around the difficult task of balancing economic and ecological considerations. Though the forests of the Pacific Northwest United States are among the most studied old-growth ecosystems, ecological and economic analyses have yielded public land management directives that remain controversial. Specifically, the recently adopted Northwest Forest Plan lacks explicit goals for maintaining intergenerational equity for the use of forest resources and the diversity of old-growth ecosystems. Unlike previous studies which rely on monetary quantification of costs and benefits, this study develops and applies a conceptual framework for evaluating socially optimal Pacific Northwest old-growth forest utilization strategies. Conditions for the optimal management of old-growth forests are derived using dynamic programming. The objective function synthesizes relevant biological and economic attributes of the old-growth allocation problem. Results in the form of extraction paths are compared given social pressure for consumptive and non-consumptive benefits, as well as different planning horizons, rates of social time preference, and environmental variance. Lengthening the planning horizon results in a vast divergence of optimal policies in the absence of discounting. Extraction rates appear to approach zero as the planning horizon approaches infinity. While higher rates of social time preference increase the rate of extraction, forest stocks remaining at the terminal time period equal levels remaining with a lower discount rate. Increasing environmental variance results in a higher level of stock remaining at the terminal time period. This analysis, while specific to the old-growth controversy of the Pacific Northwest, does provide general guidelines for addressing similar problems of multiple uses of natural areas, particularly where such uses are mutually incompatible, or where one use may be irreversibly destructive to another.  相似文献   
135.
This paper presents an integrated system for the assessmentof technical and non-technical measures that are putforward in order to reduce air pollution levels in urbanareas. In contrast to the majority of the currentlyemployed assessment tools, this system allows for theevaluation of any proposed air pollution control measure interms of its combined impact on air quality and socialwelfare, by correlating the environmental and economicaspects of alternative air pollution abatement solutions.Based on the multi-pollutant, multi-effect concept, thesystem presented aims in providing policy-makers with areliable tool for the objective assessment of the mostcost-effective packages of measures, the latter beingallocated according to the particular features and needs ofthe areas examined.  相似文献   
136.
以地市州为基本经济单元,以1999年主要相对指标为依据,通过综合值测算法,将全省划分为四类经济发展水平不同的地区,对四类地区平均总量指标、相对指标进行了对比分析,并揭示了其空间分布特征,简要分析了各类地区经济发展的条件和方向;以1999年、1978年各地市州GDP为例,对比分析了四川省区域经济不平衡发展的动态性特征。  相似文献   
137.
This paper presents result from an economic and technical point of view evaluation study, which has sought to establish the potential for replacing well-water that is currently used at the Piaggio industrial plant in Pontedera with recycled wastewater. The study is based upon a pilot wastewater treatment plant, which has been used to test wastewater treatment processes and to compare with achieved quality of recycled waters with that of water drawn on-site from physical/chemical pre-treatment and end with a reverse osmosis and air stripping stage. However, after the physical/chemical pre-treatment, the first option uses oxidation with ozone followed by activated carbon filtration, whereas the second method uses ultrafiltration. The first method is more effective at reducing chemical oxygen demand (COD) whereas the second method is more effective in removing bacteria. Nonetheless, both methods deliver water for re-use of a quality comparable with or better than that of well-water. In principle, the reverse osmosis permeate from either process could be re-used in all production phases at the industrial plant. However, the method base upon oxidation with ozone followed by activated carbon filtration is preferred, because, the process is simpler and continuous. The economic analysis of this process gives an estimated cost of Euro 0.55 per m3 for treated water. This compares favorably with other treatment processes and with the cost of other forms of water supply, which are projected to increase in any case.  相似文献   
138.
关于环境保护的可持续发展   总被引:2,自引:0,他引:2  
阐述了可持续性发展的定义和内涵,介绍了可持续性发展概念产生的历史背景和该概念不断完善和补充的过程。并论述了经济增长、环境保护与可持续性发展的关系,最后,提出了实施可持续发展战略应注意的一些问题。  相似文献   
139.
水资源供需平衡的安全分析   总被引:5,自引:1,他引:5  
从中国发展的区域基础角度,考察经济核心区和6个大区在未来经济发展中的水资源供需安全问题.在分析中应用一般均衡的分析技术和线性规划逆问题分析技术相结合,研究表明,在未来发展中水资源最紧缺的地区是华北和西北,作为经济核心区的京津唐地区水资源问题最为严重.研究提出,只有结合开源节流和调整产业结构才能保证经济发展中的水资源供应安全.  相似文献   
140.
ABSTRACT: Bringing water from Colorado River via the Central Arizona Project was perceived as the sole solution for Tucson Basin's water problem. Soon after Central Arizona Project's water arrived in Tucson in 1992, its quality provoked a quarrel over its use for potable purposes. A significant outcome of that quarrel was the enactment of the 1995 Proposition 200. The Proposition 200 precludes the use of Central Arizona Project's water for potable purposes, unless it is treated. Yet, it encourages using it for non‐potable purposes and for replenishing the Tucson aquifer through recharge. This paper examines the economic issues involved in utilizing Central Arizona Project's water for recharge. Four planning scenarios were designed to measure and compare the costs and benefits with and without Central Arizona Project's water recharge. Cost‐benefit analysis was utilized to measure recharge costs and benefits and to derive a rough estimate of cost savings from preventing land subsidence. The results indicate that the institutional requirements can be met with Central Arizona Project's water recharge. The economic benefits from reducing pumping cost and saving groundwater are not economically significant. Yet, when combining the use of Central Arizona Project's water for recharge and non‐potable purposes, it demonstrates positive net economic benefits.  相似文献   
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