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1.
The purpose of the United Nations' mineral exploration activities is to assist the developing countries in identifying, evaluating and developing their mineral resources as a means of stimulating their economic development. Since 1978, these programmes have been executed by the Natural Resources and Energy Division of the Department of Technical Co-operation for Development (DTCD) with the United Nations Development Programme (UNDP) providing the bulk of the financing. In the past 30 years, more than 450 projects in some 100 developing countries have been executed at a cost estimated at US$600 million. This input has contributed to the discovery of deposits valued at billions of dollars, many of which are now being mined.  相似文献   

2.
Financial markets recognise maximisation of expected value (E), in an essentially risk-neutral context, as the main corporate financial objective of private enterprise. This may be valid for large, integrated mining companies. Yet, most junior and middle-size exploration companies behave in a risk-averse fashion when making decisions about progressively more expensive exploration programs. From their perspective, a potential increase in expected value from either an increase in target value or related probability of discovery, or both, may not be a sufficient incentive to embark in an exploration programme if the resultant increase in expected value is accompanied by a significant increase in possible maximum loss. Risk-averse explorers may be unwilling to bear larger, albeit less probable losses, when the cost of successive exploration programmes is taken into account. The paper provides a practical methodology for such explorers to optimise the decision whether to progress to the next stage of exploration or to farm out a risky project. It uses a decision-tree model incorporating the effectiveness of the proposed exploration programme, the explorer's risk tolerance and related utility values and the probability distribution of the possible value of the exploration target.  相似文献   

3.
Countries that rely on private investors to find and exploit their mineral resources need reliable indicators of their investment attractiveness. This study explores the use of exploration expenditures for this purpose, focusing primarily on Chile.  相似文献   

4.
In this paper, a standard exploration activities model is modified and applied to time series, data from deep seabed mining of a group of minerals where the number of patents is used as a proxy, for the level of mineral exploration activities. In addition to the rational expectations model, price, expectations formation for mineral prices is decomposed into trend and cyclical components using the, HP-filter method. Estimated parameters from the supply and cost functions are used to determine the, shadow price of the minerals. The non-linear instrumental variables estimator is employed to estimate, the exploration activities function. While the rational expectations model shows the importance of, current prices on exploration efforts, the HP-filter model suggests that firms concentrate on the trend, in prices rather than the short-run cyclical fluctuations. Also, while the U.S. refusal to ratify the LOSC, has increased the legal uncertainties surrounding the management of ocean resources and reduced the, incentive to engage in exploration activities, the passage of the ISA's main legislative accomplishment, regarding regulation of the explorations for polymetallic nodules appear to have made a positive effect.  相似文献   

5.
The EU is committed to encourage biological treatments of organic waste as an alternative to landfill and also to enhance organic matter recycling. When these wastes are composted, the composition of the initial raw materials is very important in order to obtain a good quality product. In this article, the mineral composition of the organic fraction obtained from source-sorted collection (SC) and the organic fraction mechanically separated (MS) from mass-collected municipal solid waste was evaluated. Also, the compositions of these 2 raw materials that are used in the current Spanish municipal solid waste biological treatment facilities were compared. The mineral elements analyzed were the total content of the heavy metals Zn, Cu, Ni, Cr, Pb and Cd, and the plant nutrients P, K, Na, Ca, Mg, Fe and Mn. The results obtained were expressed on dry matter basis and on mineral matter basis. Important differences were detected between SC and MS samples, on both dry and mineral matter basis. In general, nutrient contents are higher in SC than in MS, and heavy metal contents are significantly lower in SC. Our results also support the idea that the heavy metal migration from the non-compostable materials to the decomposable matrix takes place from the beginning of the process while both types of materials are in contact.  相似文献   

6.
Effect of mineral and manure phosphorus sources on runoff phosphorus   总被引:3,自引:0,他引:3  
Concern over nonpoint-source phosphorus (P) losses from agricultural lands to surface waters has resulted in scrutiny of factors affecting P loss potential. A rainfall simulation study was conducted to quantify the effects of alternative P sources (dairy manure, poultry manure, swine slurry, and diammonium phosphate), application methods, and initial soil P concentrations on runoff P losses from three acidic soils (Buchanan-Hartleton, Hagerstown, and Lewbeach). Low P (12 to 26 mg kg(-1) Mehlich-3 P) and high P (396 to 415 mg kg(-1) Mehlich-3 P) members of each soil were amended with 100 kg total P ha(-1) from each of the four P sources either by surface application or mixing, and subjected to simulated rainfall (70 mm h(-1) to produce 30 min runoff). Phosphorus losses from fertilizer and manure applied to the soil surface differed significantly by source, with dissolved reactive phosphorus (DRP) accounting for 64% of total phosphorus (TP) (versus 9% for the unamended soils). For manure amended soils, these losses were linearly related to water-soluble P concentration of manure (r2 = 0.86 for DRP, r2 = 0.78 for TP). Mixing the P sources into the soil significantly decreased P losses relative to surface P application, such that DRP losses from amended, mixed soils were not significantly different from the unamended soil. Results of this study can be applied to site assessment indices to quantify the potential for P loss from recently manured soils.  相似文献   

7.
Pietro Guj   《Resources Policy》2011,36(1):80-90
Although the “real option valuation” (ROV) methodology offers extremely valuable insights in optimising investment decisions in the face of uncertainty, its practical acceptance in the mining industry has until recently been slow because of its perceived computational complexity. Recent conceptual advances in the use of binomial lattices and software developments in the areas of decision trees and dynamic programming, have significantly simplified ROV analysis and made it of practical application in day-to-day financial evaluations and decisions involving uncertainty. This paper provides general background on the ROV methodology and an example of how a typical farm-in/out agreement, as a preliminary to the establishment of a joint venture (JV), can be valued as a series of sequential and compound real options. For illustrative and quality assurance purposes, a simple farm-in/out agreement is valued from the point of view of the party acquiring equity in the project (the farm-inee) using two distinct methods, i.e. (a) a binomial lattice and (b) a decision tree in combination with binomial stochastic processes, in both cases neutralising risk using the user-friendly “risk-neutral probability”. The fact that exactly the same ROV is obtained by both methods provides confidence in the modified decision tree approach, which opens up the capacity to value the more complex sequential/compound real options inherent in real-life farm-in/out agreements. The model is then modified to incorporate a number of realistic contractual conditions often encountered in typical exploration and mining farm-in/out deals. The paper demonstrates how the increased complexity of the model can be relatively easily addressed using a decision tree with dynamic programming capability.  相似文献   

8.
9.
The degree of security of investment afforded by the applicable legal regime is one of the most important factors affecting minerals projects. This article outlines the deep-sea mining regime contained in the recently adopted Law of the Sea Convention. A history of subsea mining, including petroleum mining, is presented and the events leading to adoption of the Convention are described. Those parts of the Convention relating to deep-sea mining are analysed, and the International Sea-Bed Authority is examined. It is concluded that deep-sea mining on a commercial scale is unlikely before the end of the decade.  相似文献   

10.
本文在介绍加拿大开发生态旅游模式和经验的基础上,对我国生态旅游的发展提出了转变开发模式,科学测定旅游环境生态承载力,建立以政府为主导的旅游机构等具体建议。  相似文献   

11.
12.
Resource-rich states throughout the developing world are prone to rent-seeking, excessive borrowing, wasteful spending, and unbalanced growth as well as states with weak institutions and authoritarian regimes. Are the five energy-rich Soviet successor states necessarily doomed to repeat this experience, often referred to as the “resource curse”? This paper advances and tests the hypothesis that Russia and Kazakhstan are more likely to avoid the “resource curse” than Uzbekistan, Turkmenistan, and Azerbaijan because they privatized their energy sectors. Specifically, we find that privatization offers a potential path out of the “resource curse” when it involves a transfer of ownership to domestic actors. Although Kazakhstan initially appeared to be developing a viable tax regime in response to foreign investors, over the long term Kazakhstan’s tax regime has become increasingly volatile and dependent upon these foreign investors. In contrast, domestic oil companies are helping to foster the development of an increasingly viable tax regime in Russia.  相似文献   

13.
The purpose of this article is to broaden understanding of the factors which exert major influences on prices for industrial metals beyond the widely recognized tendency for prices and inventories to move in opposite directions. Specifically, the relationship between inventory levels and price volatility is examined. In addition, the relationship between prices and production costs is also examined. A few thoughts are expressed on the relationship between prices and industry structure. The paper includes a qualitative discussion about why a link should exist between prices and production costs, a graph illustrating the relationship between prices and inventories, and econometric equations quantifying the relationship between prices, production costs and inventories.  相似文献   

14.
结合全国以及福建省环境管理信息化的实践经验,提出了狭义的云概念和面向全省各级环境主管部门的基于云平台的信息化建设思路。将新一代信息技术充分融入到环境综合管理应用中去,并从架构、技术应用及效益几个方面进行了分析,是“十二五”期间福建省环境信息化大踏步迈进的有力探索。  相似文献   

15.
The sulphur dioxide and nitrogen oxides emissions from all sources in Alberta, Canada, during 1982 amounted to 488,297 and 353,511 tonnes, respectively. During this year deposition of wet sulphate from all stations in the province, 8 kg ha–1 yr–1, compares well with the five-year average (1978–1982) value of 10 kg ha–1 yr–1. These measurements are about one-half of the wet sulphate deposition criteria of 20 kg ha–1 yr–1 established for protecting the moderately sensitive aquatic ecosystem in eastern Canada. Due to dry, cold, continental climate conditions of Alberta, dry sulphate or sulphur deposition is equally or more important than wet deposition. No effects of the long-range transport of atmospheric pollutants (LRTAP) on the ecosystems in Alberta have been observed to date. Atmospheric deposition target loadings of SO4 –2, NO3 , and H+ for Alberta and western Canadian environmental conditions should be developed to protect the highly sensitive ecosystems. Some future research and monitoring priorities for Alberta and western Canada are outlined.  相似文献   

16.
A tax on waste-to-energy incineration of fossil carbon in municipal solid waste from households was introduced in Sweden on July 1, 2006. The tax has led to higher incineration gate fees. One of the main purposes with the tax is to increase the incentive for recycling of materials, including biological treatment. We investigate whether and to what extent this effect can be expected. A spreadsheet model is developed in order to estimate the net marginal cost of alternative waste treatment methods, i.e., the marginal cost of alternative treatment minus avoided cost of incineration. The value of the households’ time needed for source separation is discussed and included. The model includes the nine largest fractions, totalling 85% (weight), of the household waste currently being sent to waste incineration: food waste, newsprint, paper packaging, soft and hard plastic packaging, diapers, yard waste, other paper waste, and non-combustible waste. Our results indicate that the incineration tax will have the largest effect on biological treatment of kitchen and garden waste, which may increase by 9%. The consequences of an incineration tax depend on: (a) the level of the tax, (b) whether the tax is based on an assumed average Swedish fossil carbon content or on the measured carbon content in each incineration plant, (c) institutional factors such as the cooperation between waste incinerators, and (d) technological factors such as the availability of central sorting of waste or techniques for measurement of fossil carbon in exhaust gases, etc. Information turns out to be a key factor in transferring the governing force of the tax to the households as well improving the households’ attitudes towards material recycling.  相似文献   

17.
Mining generates risk of environmental and social harm for Indigenous peoples but can also generate substantial revenues for them, creating opportunities for community development in a context where economic and social disadvantage is the norm. Especially as mining revenues should, in part, compensate for mining’s negative social and environmental impacts, it is vital that mineral taxation on Indigenous lands reflect a careful assessment of appropriate tax mechanisms and a matching of these with community priorities. Yet little has been written that could serve as a guide for Indigenous decision makers. This article contributes to an understanding of the issues and choices facing Indigenous communities in designing mineral taxation regimes, by focusing on the question of economic risk. Risk arises as a key variable in choosing or designing a mineral taxation regime in three ways. Different approaches to mineral taxation are inherently more or less risky, in the sense that they are more or less certain to generate tax revenues. A second aspect of risk involves the degree of economic certainty or predictability associated with different types of commodities and projects. Third, the risk tolerance of Indigenous peoples and communities can vary significantly. We show how Indigenous groups can integrate and address these different dimensions of risk, by recognising the ‘risk consequences’ associated with different approaches to mineral taxation and choosing an approach that reflects, as fully as possible, the group’s risk tolerance.  相似文献   

18.
Representative Landscapes in the Forested Area of Canada   总被引:1,自引:0,他引:1  
Canada is a large nation with forested ecosystems that occupy over 60% of the national land base, and knowledge of the patterns of Canada’s land cover is important to proper environmental management of this vast resource. To this end, a circa 2000 Landsat-derived land cover map of the forested ecosystems of Canada has created a new window into understanding the composition and configuration of land cover patterns in forested Canada. Strategies for summarizing such large expanses of land cover are increasingly important, as land managers work to study and preserve distinctive areas, as well as to identify representative examples of current land-cover and land-use assemblages. Meanwhile, the development of extremely efficient clustering algorithms has become increasingly important in the world of computer science, in which billions of pieces of information on the internet are continually sifted for meaning for a vast variety of applications. One recently developed clustering algorithm quickly groups large numbers of items of any type in a given data set while simultaneously selecting a representative—or “exemplar”—from each cluster. In this context, the availability of both advanced data processing methods and a nationally available set of landscape metrics presents an opportunity to identify sets of representative landscapes to better understand landscape pattern, variation, and distribution across the forested area of Canada. In this research, we first identify and provide context for a small, interpretable set of exemplar landscapes that objectively represent land cover in each of Canada’s ten forested ecozones. Then, we demonstrate how this approach can be used to identify flagship and satellite long-term study areas inside and outside protected areas in the province of Ontario. These applications aid our understanding of Canada’s forest while augmenting its management toolbox, and may signal a broad range of applications for this versatile approach.  相似文献   

19.
The objective of this paper is to compare the nature of the taxation schemes facing uranium mine operators in Australia's Northern Territory and in Canada's Province of Saskatchewan. The findings demonstrate that, although the Canadian system appropriates up to 85% of incremental sales revenue, it is extremely sensitive to industry profitability. Its Australian counterpart is, in contrast, a regressive scheme which, at the current selling price of yellowcake, captures a significantly larger proportion of available economic rent.  相似文献   

20.
Valuing freshwater salmon habitat on the west coast of Canada   总被引:3,自引:0,他引:3  
Changes in land use can potentially reduce the quality of fish habitat and affect the economic value of commercial and sport fisheries that rely on the affected stocks. Parks and protected areas that restrict land-use activities provide benefits, such as ecosystem services, in addition to recreation and preservation of wildlife. Placing values on these other benefits of protected areas poses a major challenge for land-use planning. In this paper, we present a framework for valuing benefits for fisheries from protecting areas from degradation, using the example of the Strait of Georgia coho salmon fishery in southern British Columbia, Canada. Our study improves upon previous methods used to value fish habitat in two major respects. First, we use a bioeconomic model of the coho fishery to derive estimates of value that are consistent with economic theory. Second, we estimate the value of changing the quality of fish habitat by using empirical analyses to link fish population dynamics with indices of land use in surrounding watersheds. In our example, we estimated that the value of protecting habitat ecosystem services is C$0.93 to C$2.63 per ha of drainage basin or about C$1322 to C$7010 per km of salmon stream length (C$1.00=US$0.71). Sensitivity analyses suggest that these values are relatively robust to different assumptions, and if anything, are likely to be minimum estimates. Thus, when comparing alternative uses of land, managers should consider ecosystem services from maintaining habitat for productive fish populations along with other benefits of protected areas.  相似文献   

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