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1.
In cost-benefit analysis, natural resources, like other factors of production, should be costed as a mixture of marginal social cost of exploiting additional resources and lost marginal social benefit of forgone alternative uses, according to the way in which extra resources are made available to a project. For a nonrenewable resource, changes in future marginal social cost and marginal social benefit are likely to add significantly to the immediate elements of cost, as successively less tractable resource stocks are exploited. Of the several reasons given for ignoring these future costs, the most plausible is that technological advance justifies a heavy discount on the future. However, neither historical nor logical arguments demonstrate the inevitability of efficacious technological advance.  相似文献   

2.
We present a simple dynamic model to get some key insights about the substitution of renewable for nonrenewable resources and the consequences for sustainability. We highlight the role of the elasticity of substitution (technological component) to determine the adjustment of production as a response to scarcity and growing ability of resources (environmental component). In some cases, the model predicts a smooth substitution of renewable for nonrenewable resources, but this process could work in the opposite direction if renewable resources are temporarily beyond their maximum sustainable yield, so that their marginal natural growth is negative. If substitution possibilities are high enough, it may be optimal to suspend the extraction of a resource to allow the biomass to regenerate. A production process is more likely to be sustainable the more heavily it depends on renewable, rather than nonrenewable resources.  相似文献   

3.
The production of biodiesel using oleaginous microorganisms is investigated as promising alternative to produce a truly sustainable and renewable transportation fuel. While the feasibility of this approach has been shown on the laboratory scale, a commercial scale implementation is to date inhibited due to economic restraints. In order to evaluate the current cost situation and to develop suggestions to reduce production related costs, a simple cost analysis of the proposed microbial oil production process has been carried out. For closed fermentation in large-scale fermenters a break-even price of 2,350 US$ t–1 for microbial oil was calculated. In the context of a sensitivity analysis it was shown that especially alterations in capital cost can lead to overall cost reductions. Accordingly, an open pond cultivation approach was designed, cutting the cost for equipment almost in half and decreasing the break-even price to 1,723 US$ t–1. However, these reductions are only feasible when stable biomass and lipid yields can be ensured in open-pond systems, because the sensitivity analysis identified these yield parameters as leading factors influencing the break-even price. Even under very optimistic assumptions, it was not possible to reduce the break-even price below that of conventional plant oils as competitive products. Therefore, economic feasibility of the process will probably only occur if on one hand considerable technical development and efficiency improvements of the production process are made while on the other hand plant and crude oil prices are continuously increasing.  相似文献   

4.
The oil crisis has ended on a worldwide scale. Risks of excessive price rises have disappeared. Between now and the year 2000, oil resources costing less than $15/bbl (1988 dollars) will be abundant. Twenty to 25% of the oil consumed in 2000 for thermal uses will be replaced by less costly natural gas and coal. Consumption of these last two energy sources will increase if the cost of oil rises above $20/bbl (1988 dollars). The cost of oil will rise sharply when it becomes reserved for the uses for which it is irreplaceable, ie transport, petrochemicals, the Third World and non-energy uses — probably after 2010.  相似文献   

5.
This article documents, in the cases of Libya and Egypt, situations that occur in many other nations: conversion of farmlands to nonagricultural uses, exhaustion of nonrenewable water resources, irrigation leading to waterlogging and salinization of agricultural lands, development that does not benefit people in the regions being developed, etc. It is suggested that use of natural resources should be in accord with nationally determined priorities and should occur in a sustainable manner.  相似文献   

6.
本文采用能值分析和数据包络分析方法,构建了城市物质代谢生态效率的度量模型,从代谢流量和生态效率两个角度评价了南京市生态经济系统1990~2010年间的可持续发展情况。结果表明:(1)21年来,南京地区的能值产出率和可持续指标不断降低,环境负载率呈持续增长趋势;(2)南京城市系统生态效率总体呈波动上升趋势,1990~2006年间资源生态效率一直低于环境生态效率,2006年后开始有所提升。虽然南京市生态效率有所提高,但未来的发展面临快速增长的环境压力等阻碍。为此,南京应优化进口能值组成,加大可更新资源开发力度,提高不可更新资源利用率,实现废弃物资源化等。  相似文献   

7.
Based on the most comprehensive field research ever conducted in corporate environmental management, this article reports on the integration of environmental impacts into product costing and cost management practices in organizations. It examines approaches for identifying and tracking current environmental costs related to both current and past production. It also develops the need and prospects for a complete analysis of future environmental impacts, including both costs and benefits, and the integration of these elements into a life-cycle costing or full environmental cost accounting model. The prospects for full environmental cost accounting and the related accounting issues are analyzed. Finally, the importance of full environmental cost accounting for improving corporate environmental performance, reducing corporate environmental impacts, and increasing long-term corporate profitability is discussed.  相似文献   

8.
Wildlife management is a large, complex, decisionoriented science. Information from research is needed to improve the decisions made by managers. The scope of the research needed to inform typical decisions far exceeds even the most optimistic assumptions about the available funds, time, or human resources. An argument is made that while changes within the current management structures are unlikely, continuing classical experimental research alone will not meet the timely needs of the field or of citizens dependent on wildlife resources. Continuing in such a no-win game seems to be a misallocation of time and funds. Significant changes are called for and suggestions for such changes are made: discussions with people in other broadly defined fields with a similar problem, new sampling strategies, increased use of computer models, use of geobased information systems, use of game theory, nonspecies research grouping, new funding structures, and sharing of facilities and of teams of specialists.  相似文献   

9.
The USSR has long been regarded as a resource-rich country with no need for external sources of non-fuel mineral resources. Increasingly, however, it is beginning to appear that such an assessment of the Soviet non-fuel mineral resource picture is overly optimistic. The Soviet mineral industry is beset by a variety of problems which complicate the extraction and utilization of needed minerals. The USSR remains a resource-rich country, but the difficulties it encounters exploiting its resources are multiplying. This article examines the Soviet aluminium, chromium, cobalt, copper, gold, iron, lead, manganese, platinum, titanium and zinc industries, and offers views of the Soviet resource future in each area.  相似文献   

10.
The Coase theorem depends on a number of assumptions, among others, perfect information about each other's payoff function, maximising behaviour and zero transaction costs. An important question is whether the Coase theorem holds for real market transactions when these assumptions are violated. This is the question examined in this paper. We consider the results of Danish waterworks' attempts to establish voluntary cultivation agreements with Danish farmers. A survey of these negotiations shows that the Coase theorem is not robust in the presence of imperfect information, non-maximising behaviour and transaction costs. Thus, negotiations between Danish waterworks and farmers may not be a suitable mechanism to achieve efficiency in the protection of groundwater quality due to violations of the assumptions of the Coase theorem. The use of standard schemes or government intervention (e.g. expropriation) may, under some conditions, be a more effective and cost efficient approach for the protection of vulnerable groundwater resources in Denmark.  相似文献   

11.
The objective of the study is to compare different development scenarios of a black water source-separation sanitation system (BWS) that could be environmentally and economically more viable than a conventional system (CONV). Scenarios performance is evaluated using life cycle assessment and environmental life cycle costing. System boundaries include the processes related to the collection and treatment of wastewater and organic kitchen refuse collection and the recycling of by-product (digestate/sludge and biogas) produced in the treatment step. The BWS scenario that entails a vacuum toilet flow-volume reduction to 0.5 L/flush results in significantly higher performances than the ones of CONV for the climate change and resources indicators, while involving a significantly lower performance with regards to human health and a comparable cost. The BWS scenario based on digestate mass reduction with reverse osmosis and acidification prior to its transport to farmland achieves comparable performances to the ones of CONV for all indicators. The BWS scenario with digestate treatment by means of phosphorus precipitation (struvite) and nitritation–anammox reactors gives performances that are comparable to the ones of CONV for all indicators, with the exception of climate change, for which this scenario has a significantly lower performance if the electricity is produced by hydropower. When single-pathway scenarios are combined, the multi-pathway scenarios thus created can produce results that are significantly superior to the CONV result for the climate change, resources and human health indicators although the cost remains comparable.  相似文献   

12.
Following the Boskin et al., (1996) report, it became widely recognized that price indexes in the U.S. and elsewhere overstate inflation. Svedberg and Tilton (2006) highlighted that this inflation bias may have important implications for estimated long-term trends in nonrenewable resource prices. ST construct an inflation-bias corrected CPI (and PPI) for the U.S. and use their corrected deflator(s) to define a so-called ‘real real’ price of copper. Their ‘real real’ price of copper is then used to re-estimate long-term trends in real copper prices. This paper proposes a quick method for obtaining inflation-bias-corrected estimates of long-run trends in real primary commodity prices directly from estimates in the published literature. Our approach obviates the need re-do existing empirical studies using a corrected or ‘real real’ price of nonrenewable resources. The two approaches are mathematically equivalent.  相似文献   

13.
World water dynamics: global modeling of water resources   总被引:19,自引:0,他引:19  
The growing scarcity of fresh and clean water is among the most important issues facing civilization in the 21st century. Despite the growing attention to a chronic, pernicious crisis in world's water resources our ability to correctly assess and predict global water availability, use and balance is still quite limited. An attempt is documented here in modeling global world water resources using system dynamics approach. Water resources sector (quantity and quality) is integrated with five sectors that drive industrial growth: population; agriculture; economy; nonrenewable resources; and persistent pollution. WorldWater model is developed on the basis of the last version of World3 model. Simulations of world water dynamics with WorldWater indicate that there is a strong relationship between the world water resources and future industrial growth of the world. It is also shown that the water pollution is the most important future water issue on the global level.  相似文献   

14.
Effective assessment of nonrenewable resources depends on both the availability and the interpretation of basic data. The quality of these data directly affects resource policy decisions based on them. It is vital to bring information on reserves and resources into sharper focus, by clearer definition of what has been measured, by orderly classification and by identification of the results of assessment in a way that stimulates their proper understanding and application. As part of the overall programme of the United Nations Centre for Natural Resources, Energy and Transport in the field of natural resources, an Expert Group was convened in New York from 28 March to 4 April to discuss a series of such basic questions concerning the international classification and measurement of crude oil and natural gas resources. Key conceptual principles and definitions were agreed as a basic framework within which governments could work towards an internally consistent and comprehensive international exchange of information. The Group also examined problems of measurement and the manner in which existing national data would be incorporated into an international classification. The report of the Group is reproduced in full below.  相似文献   

15.
ABSTRACT Both because of its effectiveness and ease in use, linear programming has become progressively popular in water resources planning problems. Yet, the assumptions of linear construction costs can be misleading. Diseconomies of scale in construction can be handled by successive approximations to the cost function but problems with economies of scale yield paradoxical results when piecewise approximations are used. If significant economies of scale exist in only one facility, the solution to problems of this nature can be found using normal linear programming codes by successively adjusting the unit construction cost on that single facility to iteratively work toward the true optimal solution.  相似文献   

16.
不确定条件下矿产资源的最优开采   总被引:2,自引:0,他引:2  
通过一个连续时间的随机动态规划模型,探讨了市场需求、资源存量的不确定性以及勘探活动对矿产资源价格和开采速度的影响,并给出了随机条件下Hotelling法则的表达形式.模型结果显示:不确定性对资源价格变化速度的影响主要取决于开采成本,如果相对于资源存量来说开采成本是不变的或者开采的规模成本是不变的,则不确定性对资源价格的变化速度没有影响.反之,如果开采的规模成本是递增的,则不确定性会加速资源价格的变化.此外,不确定性的存在将加快资源的开采速度.至于勘探活动,它一方面降低了地质条件的不确定性,另一方面增加了资源的存量,所以勘探活动降低了资源价格和开采速度的变化率,减少了不确定性对资源开采的影响.  相似文献   

17.
Concern for the supply of resources—renewable and nonrenewable—has been evident during the 1970s. All countries seek to increase the economic and social returns from the exploration, processing and distribution of minerals so as to improve the quality of life of their people. Proper resource management is imperative because of the interdependence of the mineral sector with other leading sectors of the economy and also because of the importance of minerals in the web of international economics. This paper emphasises the significance of recent international events as they affect the mineral industry and the Canadian position in the ever changing world of resource diplomacy.  相似文献   

18.
As uranium has practically no other industrial uses besides electricity generation, demand is determined by the requirements and stockpiling policies of electric utilities. The uranium market has experienced strong fluctuations and is currently affected by the reductions in nuclear forecasts resulting from the slowdown in electricity demand. Analysing supply/demand indicators proves, however, that in retrospect the development has been relatively smooth and it appears that oversupply is more a consequence of overly optimistic short-term expectations. In the future, especially in the long term, nuclear power policies continue to be concerned with striking a proper balance between increasing production capability and development of new reactor technologies which would be less dependent on the availability of uranium. A bounding scenario approach is applied in this article to the assessment of adequacy of supply under varying assumptions on the total installed nuclear capacity, available resource base and attainable production capability.  相似文献   

19.
The separate effects of 50% increases in the prices of energy, renewable and nonrenewable natural resource inputs on factor demands and production costs are simulated for Canadian total manufacturing and six two-digit industries. Both renewable and nonrenewable natural resource price increases have a substantially greater effect upon the demands for other factors and upon production costs than a parallel energy price increase. These results are important from a policy perspective and justify the further disaggregation of inputs in this and in other models of input demand.  相似文献   

20.
中国煤电行业的发展伴随着各种环境风险,本文以典型煤电企业为例,在产能过剩、能效标准提高、环境保护税、全国碳市场、水资源税和非水可再生能源规划目标的风险约束下,建立环境成本内部化和环境风险分析工具,考虑不同压力情境下对煤电企业价值的影响,构建环境风险影响财务成本的压力测试框架。结果表明,对单个风险而言,产能过剩和碳市场风险对企业价值的影响是大多数地区在不同情景中面临的主要风险驱动因素。对于综合风险压力测试而言,各地区1 000MW超超临界机组乐观情景及悲观情景的企业价值距合理回报预期企业价值相差小,而300MW和600MW亚临界机组因能效水平低、经营成本高等原因在环境风险压力下企业价值偏离合理回报较多。随着环境风险严重程度的不断增加,环境压力测试有助于煤电企业和金融机构了解环境风险对企业财务状况的影响,从而对投资决策产生影响。  相似文献   

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