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1.
China has embarked on major economic and social changes to revitalize the Chinese economy, increase labor productivity, and improve the material standard of living of the Chinese people. This paper assumes that China will achieve its goal of a per capita income of US$800 in 2000, open-door policies will be maintained, and nonfuel mineral commodity consumption will increase as GDP per capita increases. Projections are made of production, trade and consumption of 14 nonfuel minerals for the period 1985–2005. China is projected to increase its net imports to these 14 minerals from about US$5000 million in 1985 to about US$12000 million in constant dollars in 2005. China's investment climate will become more favorable for those multinational companies that bring with them clear comparative advantages in minerals exploration, mining and processing technologies and marketing, and are prepared to develop in-depth Chinese expertise.  相似文献   

2.
Yellow starthistle (Centaurea solsitialis L.) is an invasive weed that creates problems for the management of Idaho's rangelands. A bioeconomic approach combined with an input-output economic model is used to estimate direct and secondary economic costs of the weed in relation to its interference with agricultural and non-agricultural benefits that rangelands provide. Direct economic costs of the infestations were estimated to be of 8.2 million '05 dollars per year, and secondary costs of 4.5 million '05 dollars per year, for a total of 12.7 million '05 dollars; agricultural related economic impacts accounted for 79% of this total cost, and non-agricultural for 21%.  相似文献   

3.
A contingent valuation survey of users of the 140 km Ridgeway National Trail was undertaken to estimate the value that users place on access to the Trail. The survey found that users had a mean willingness to pay for access to the Ridgeway of £1.24 per visit (£1.13– £1.36 95% Confidence Limits). With around 150 000 visits to the Ridgeway each year, this gives an estimated annual aggregate benefit of £186 000 (£169 500– £204 000 95% Confidence Limits) plus the economic benefits to local economies of visitor spending of some £0.8 million. This compares with the costs of Trail maintenance of around £154 000 per year. The development of National Trails in England for recreation and tourism is also discussed.  相似文献   

4.
ABSTRACT The Colorado River Basin faces the dilemma of an increasing demand for water while presently struggling with salinity concentrations approaching critical levels for some water uses. Based upon projected development salinity concentrations are predicted to exceed 1200 mg/1 at Imperial Dam by the year 2010. Annual losses to the basin economy associated with increased salinity will exceed $50 million by the year 2010. Although methods of controlling salt discharges are relatively unrefined, certain conclusions, based upon Bayesian statistical methods, can be reached. Five basic alternatives for coping with the problem are presented and evaluated in this paper: (1) do nothing; (2) adopt arbitrary salinity standards; (3) limit development; (4) control salt discharges at a cost equal to the cost of doing nothing, or (5) minimize total costs to the basin. Total costs associated with any given alternative, or the given salinity resulting, are the sum of salinity detriments (cost to users for water of increased salinity plus economic multiplier effects) plus the cost of constructing salt discharge control works. These impacts upon basin economy and Colorado River water quality for each alternative are presented and related to questions of equity which will play a role in arriving at any long-term solution to the Basin's problem.  相似文献   

5.
A significant amount of mineral aggregates are used in constructing, rehabilitating and maintaining roads. As local (nearby) quarries get exhausted, aggregates need to be hauled from sources that are at ever-greater distances. Hence, over time the cost of trucking as well as the amount of emissions generated by trucking increases with a decrease of local natural aggregate stocks. The objectives of this study are to construct and utilize a system dynamics model of the depletion of a stock of natural aggregates due to pavement construction and maintenance, and determine the effect of using local and nonlocal aggregates, recycling and project cancellation (slowing growth) on the paving of roads. Long-term simulations are carried out with available aggregate stock, trucking distance and cost data. The quality of roads and a sustainability score, based on engineering, economic and environmental factors (emissions) are evaluated for different scenarios. An optimal combination of the use of local and nonlocal recycled aggregates, recycling and project cancellation is recommended. The proposed system dynamics model could be utilized by agencies to plan for the proper utilization of aggregate resources for road development and maintenance/rehabilitation projects.  相似文献   

6.
Projected increases in demand and thus increasing metal prices have brought the exploration and exploitation of marine mineral resources back into focus. The Atlantis II Deep, located in the central Red Sea between Saudi Arabia and Sudan, is one of the largest marine sulfide deposits known, with high concentrations of metals such as zinc, copper, silver and gold. However, little is known about the economic potential of marine minerals as well as the legal constraints. Our geological assessment shows that the deep is similar in grades and scale to large land-based deposits. Its economic potential is far from negligible. The total present value of possible gross revenues for the four metals zinc, copper, silver and gold ranges from 3.03 to 5.29 billion US$, depending on the assumptions made concerning future price development, mass calculation and discount rate. From a legal perspective, a general duty to cooperate in the exploration and exploitation of non-living resources located in disputed maritime areas is identified in both customary international law and in UNCLOS. It is submitted that a joint development agreement is one means of ensuring compliance with this duty in general and in the case of the Atlantis II Deep in particular.  相似文献   

7.
The US Bureau of Mines has determined the potential availability of nickel from 36 deposits or districts in 16 market economy countries (MECs). More than 95% of production in MECs was analysed. The study indicates the quantity of nickel available in resources and potential annual production at net production costs and on a total cost basis with a 0% and a 10% discounted cash flow rate of return (DCFROR). The properties included in this study contain approximately 33 million tonnes of recoverable nickel. About 26 million tonnes of nickel is potentially recoverable from nickel laterite deposits, of which 4.5 million tonnes can be produced at $2.50/lb or less with a 0% DCFROR. Approximately 7 million tonnes of nickel is potentially recoverable from nickel sulphide deposits of which about 6.3 million tonnes could be produced at $2.50/lb or less at a 0% DCFROR. Sensitivity studies indicate that the total cost of producing nickel from laterite deposits is most sensitive to increases in energy costs, and that the total costs of producing nickel from sulphide deposits is most sensitive to increases in labour costs and by changes in byproduct revenues.  相似文献   

8.
To mitigate the adverse environmental impact of forest roads, especially degradation of endangered salmonid habitat, many public and private land managers in the western United States are actively decommissioning roads where practical and affordable. Road decommissioning is associated with reduced long-term environmental impact. When decommissioning a road, it may be possible to recover some aggregate (crushed rock) from the road surface. Aggregate is used on many low volume forest roads to reduce wheel stresses transferred to the subgrade, reduce erosion, reduce maintenance costs, and improve driver comfort. Previous studies have demonstrated the potential for aggregate to be recovered and used elsewhere on the road network, at a reduced cost compared to purchasing aggregate from a quarry. This article investigates the potential for aggregate recycling to provide an economic incentive to decommission additional roads by reducing transport distance and aggregate procurement costs for other actively used roads. Decommissioning additional roads may, in turn, result in improved aquatic habitat. We present real-world examples of aggregate recycling and discuss the advantages of doing so. Further, we present mixed integer formulations to determine optimal levels of aggregate recycling under economic and environmental objectives. Tested on an example road network, incorporation of aggregate recycling demonstrates substantial cost-savings relative to a baseline scenario without recycling, increasing the likelihood of road decommissioning and reduced habitat degradation. We find that aggregate recycling can result in up to 24% in cost savings (economic objective) and up to 890% in additional length of roads decommissioned (environmental objective).  相似文献   

9.
Emergy evaluation perspectives of a multipurpose dam proposal in Korea   总被引:1,自引:0,他引:1  
The 'emergy' concept was used to evaluate the economy of Korea and the contributions of a multipurpose dam proposal to the real wealth of the Korean economy. Emergy is defined as the available energy of one kind previously used up directly and indirectly to make a product or service. The indices for Korea calculated from the emergy evaluation were close to those of developed countries. Even though its monetary balance of payments was negative in 1997, the economy of Korea showed positive balance in trade when exports and imports were expressed in emergy. The emergy evaluation showed that the Korean economy places a large stress on its environment. Water supply and generation of electricity were the most important contributions of the proposed dam in terms of emergy; 46.5 and 45.1% of the total benefit, respectively. Flood control contributed 8.4% of the total benefit. Major costs associated with the proposed dam were from sediments (33.2% of the total cost), construction services (22.8%), and social disruption of the region (21.6%). In terms of emergy, the ratio of benefits to costs of the proposed dam was 2.78 if sediments are not included, and 1.86 if sediments are included, which result in more benefits than costs in both cases. The benefit to cost ratio of the dam was larger than that of the current system (1.42) without the dam whether sediments are included in the total cost or not. The environmental stress of the proposed dam was considerably lower than that of the Korean economy, but the dam might increase stress on local environment.  相似文献   

10.
Economic theory asserts that to achieve maximum conservation benefits land acquisition needs to be cost effective. Yet the most common planning technique used by land conservation organizations is ‘benefit-targeting’ that focuses only on acquiring parcels with the highest benefits and ignores costs. Unlike most of the literature which focuses on covering problems, this research applies optimization techniques to achieve maximum aggregate conservation benefits for an ongoing land acquisition effort in the Catoctin Mountain Region in central Maryland. For this case study, optimization yields additional conservation benefits worth an estimated $3.1–$3.9 million or achieves the same level of conservation benefits but at a cost savings ranging from $0.9 to $3.5 million, depending on the initial budget size. Finally, the highest efficiencies are achieved in low budget scenarios, like those most prevalent in conservation efforts.  相似文献   

11.
The invasion spread of the emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is characterized by the formation of satellite populations that expand and coalesce with the continuously invading population front. As of January 2010, satellite infestations have been detected in 13 states and two Canadian provinces. Understanding how newly established satellite populations may affect economic costs can help program managers to justify and design prevention and control strategies. We estimate the economic costs caused by EAB for the 10-yr period from 2010 to 2020 for scenarios of fewer EAB satellite populations than those found from 2005 to 2010 and slower expansion of satellite populations found in 2009. We measure the projected discounted cost of treatment, removal, and replacement of ash trees (Fraxinus spp.) growing in managed landscapes in U.S. communities. Estimated costs for the base scenario with the full complement of satellites in 2005-2010 and no program to mitigate spread is $12.5 billion. Fewer EAB satellites from 2005 to 2010 delay economic costs of $1.0 to 7.4 billion. Slower expansion of 2009 satellite populations delays economic costs of $0.1 to 0.7 billion. Satellite populations that are both distant from the core EAB infestation and close to large urban areas caused more economic costs in our simulations than did other satellites. Our estimates of delayed economic costs suggest that spending on activities that prevent establishment of new satellite EAB populations or slow expansion of existing populations can be cost-effective and that continued research on the cost and effectiveness of prevention and control activities is warranted.  相似文献   

12.
The impact of commodity price risk management on the profits of a company   总被引:1,自引:0,他引:1  
It is well recognized that for the producing companies hedging the commodity price using financial products like forwards or futures has become an important part of the company's production process. But apart from the direct impacts of hedging on the production and hedging costs the use of financial products affects the financing of the company: hedging the volatile commodity prices leads to a reduction of the risk premium the company has to pay for its debt capital, since hedging contributes to more confidence of the investors in the redemption of the debt. In this paper we therefore analyze this dependency of hedging and financing and derive optimal hedging extents for companies in different market situations based on a long-term model. By hedging the commodity price, companies can realize a surplus in profits. Thereby, the optimal hedging extent for a monopolist is often up to 100%, whereas for companies in a polypolistic market the optimum is always less than 100%. These results are illustrated by examples for a producing company.  相似文献   

13.
In 2007, in England, the Department of Environment, Food and Rural Affairs (Defra) published Waste Strategy 2007 for England. To help drive the required behaviour change for increased sustainable practice the Government in England signalled up in the Strategy the intention to launch a Zero Waste Places (ZWP) initiative to develop innovative and exemplary practice. By inviting places (including cities, towns and rural communities) to bid for ZWP status, the successful applicants were then expected to become exemplars of good environmental practice on all waste issues. The ZWP programme commenced in October 2008 with the selection of 6 distinct places based upon an application by a partnership containing a Local Authority or in one case a Regional Development Agency. The places ranged in size from the very small (one street of 201 properties) to a Region of England (5 million population). These 6 were chosen from an initial list of 12 applicants via a rigorous selection process against fixed criteria that were designed to support Zero Waste practice. The funding was £70,258 and the mean was £11,709. The overall assessment suggests that the Local Authorities and their project partners rose to the challenge of zero waste and in most cases met or even exceeded their objectives (meeting at least 80% of aims and planned actions) and achieved high value for money in terms of Government funded initiatives. Evaluation suggested that there is a requirement to link, in the future, ZWP initiatives with other recent developments such as Transition Towns, Eco-Town and Total Place developments within Local Authorities. A Certificated Standard for ZWP was developed and is perceived as being both useful and valuable and it is hoped that it will spur a large number of new ZWP applications.  相似文献   

14.
With China's rapid economic development, environmental problems have become more and more serious. Particulate air pollution is terrible in cities with large and dense population. It may lead to adverse health effects and economic costs. In this study, we calculated the health effects of pollution caused by particulate matter with aerodynamic diameters less than 10mum (PM(10)) in 111 Chinese cities in 2004 according to statistical data and epidemiological exposure-response functions. Using economic burden of disease analysis, an economic assessment of these health risks was also presented. In contrast to many previous studies that have examined individual cities, this study covered most large and medium-sized cities in China, which accounted for more than 70% gross domestic product (GDP) of China in 2004. The total economic cost caused by PM(10) pollution was estimated as approximately US$ 29,178.7 million. Mega cities such as Beijing, Shanghai, and Tianjin contribute relatively more to the total costs. The results will help policy makers in formulating more effective countermeasures and increasing public awareness to enhance environmental protection.  相似文献   

15.
Marine constructions are highly vulnerable to climate change and sea-level rise (SLR), leading to increased risk rates of destruction and the potential closure of ports, harbors, and marinas along the coast. We present a cost-adjustment analysis for such constructions along the south-eastern Mediterranean coast, which takes into account the physical characteristics of the constructions, and environmental uncertainty factors. At 0.5 m SLR, the estimated adjustment cost is USD 280 million, and at 1 m SLR, the estimated cost is USD 505 million. These costs are equivalent to 0.091% and 0.165% of the Israeli gross domestic production, respectively. Although high, these adjustment costs are lower than the costs of future damage that will accrue if we fail to act. This implies that the adaptation-policy approach to controlling for the risk of SLR will provide benefits to the economic marine sectors and the public at large.  相似文献   

16.
The paper describes a contingent valuation study of the benefits and costs of the Wildlife Enhancement Scheme (WES) (English Nature) on the Pevensey Levels Site of Special Scientific Interest in East Sussex, England. Using a conventional mean WTP value as the appropriate measure of benefits gave a benefit/cost (B/C) ratio of 0.497 for user value and 1.994 for user plus non-user values (households within 60 km of the site) for expenditure under WES. If a more rigorous and conservative truncated mean value was employed, then B/C ratios fell to 0.117 for user values and 0.758 for user plus non-user values. However, assuming the same level of passive use values are held by a similar proportion of all non-visiting households in the UK as observed in the sample survey, this would produce a B/C ratio for truncated mean user plus non-user benefits of 18.26. Even if the addition of further WES sites across the country led to a steep decline in mean marginal non-user WTP for the scheme in the Levels, the B/C ratio would still greatly exceed 1.0.  相似文献   

17.
This paper presents a system dynamics computer model to evaluate alternative type of recycling center under different policy and economy environments through comparison on the economic feasibility of recycling centers and ratio of savings to costs in C&D waste management. A case study for the City of Chongqing, China is selected. Simulated results show three key factors can contribute to the economic feasibility of recycling and the ratio of savings to costs in C&D waste management: (a) profit; (b) unit recycling cost; (c) extra revenue from location advantage (It was assumed that the mobile centers can attain extra revenue from the location advantage compared with fixed recycling centers). The sensitive analysis and comparison on ratios between public and private sector indicate that to achieve the optimum ratio of savings to costs, design of recycling centers and selection of governmental instruments are determined by the priority list: (1) low extra revenue from location advantage; (2) low profit; (3) low unit recycling cost. Meanwhile, the fluctuation of the three factors must be prior to achieve economic feasibility of corresponding recycling centers.  相似文献   

18.
The Dutch disease is regularly evoked in the resource curse literature and remains a frequent explanation for the poor economic performance found in many resource-rich countries. Given Botswana's high rate of per capita GDP growth, it might seem superfluous at first glance to ask whether or not there is a Dutch disease in Botswana. Yet, Botswana merits study here both as a significant potential exception to any posited inevitability of the Dutch disease and also because the debate on whether or not Botswana has avoided the Dutch disease is far less settled than is indicated by its economic growth record. Botswana currently suffers from many of the symptoms of the Dutch disease but not for the causal reasons posited in the Dutch disease model. Indeed, many of the explanations for the lack of diversification found in Botswana's mineral-dependent economy have nothing to do with either diamond revenues or the Dutch disease. Botswana has done about as well managing its resource wealth as could realistically be expected but it is unlikely to succeed in diversifying its economy away from diamonds anytime soon.  相似文献   

19.
Although there is a burgeoning literature on the effects of international trade on the environment, relatively little work has been done on where trade most directly effects the environment: the transportation sector. This article shows how international trade is affecting air pollution emissions in the United States' shipping sector. Recent work has shown that cargo ships have been long overlooked regarding their contribution to air pollution. Indeed, ship emissions have recently been deemed "the last unregulated source of traditional air pollutants". Air pollution from ships has a number of significant local, national, and global environmental effects. Building on past studies, we examine the economic costs of this increasing and unregulated form of environmental damage. We find that total emissions from ships are largely increasing due to the increase in foreign commerce (or international trade). The economic costs of SO2 pollution range from dollars 697 million to dollars 3.9 billion during the period examined, or dollars 77 to dollars 435 million on an annual basis. The bulk of the cost is from foreign commerce, where the annual costs average to dollars 42 to dollars 241 million. For NOx emissions the costs are dollars 3.7 billion over the entire period or dollars 412 million per year. Because foreign trade is driving the growth in US shipping, we also estimate the effect of the Uruguay Round on emissions. Separating out the effects of global trade agreements reveals that the trade agreement-led emissions amounted to dollars 96 to dollars 542 million for SO2 between 1993 and 2001, or dollars 10 to dollars 60 million per year. For NOx they were dollars 745 million for the whole period or dollars 82 million per year. Without adequate policy responses, we predict that these trends and costs will continue into the future.  相似文献   

20.
Best management practices (BMPs) are widely used to mitigate impacts of increased impervious surfaces on stormwater runoff. However, there is limited detailed and up‐to‐date information available on the cost of designing, constructing, and maintaining BMPs over their lifetime. The objective of this study is to analyze BMPs recently constructed by the Virginia Department of Transportation (VDOT) to quantify their total cost per pound of phosphorus removed annually. A motivating factor for the study is recent changes to regulatory guidelines in Virginia which allow for full or partial substitution of purchased nutrient credits in lieu of constructing onsite BMPs to achieve compliance with stormwater quality regulations. Results of the analysis of nine BMPs found their cost ranged from $20,100 to $74,900, in 2014 dollars, per pound ($44,313‐$165,126 per kg) of phosphorus removed. Based on these results and assuming current credit prices procured by VDOT, purchasing nutrient credits is a cost‐effective option for the agency, especially when factoring in the cost of additional right of way for the BMP. Based on this finding, we expect compliance with stormwater quality regulations through credit purchases to become more widely used in Virginia. Moving forward, we suggest more direct tracking of BMP costs to support comparisons between BMP costs across a range of types and conditions to credit purchases for meeting stormwater regulations.  相似文献   

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