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1.
2.
The distinction between an exploitable and a non-exploitable mineral deposit is dynamic, varying as a function of changing economic and technological factors. A conceptual framework is proposed: ‘reserves’ are restricted to known currently exploitable deposits; ‘known resources’ are reserves plus currently non-exploitable deposits; ‘total resources’ are known resources plus all deposits not yet discovered. The short-term inadequacy of some mineral reserves requites a policy of accelerated mineral exploration and rapid development of new exploration techniques. Future problems could be avoided if the nature of resources is recognized and new mineral extraction and processing techniques for lower grade and unconventional mineral deposits are developed.  相似文献   

3.
National reporting organizations and regulatory bodies for the minerals and mining sector are requiring publicly reported Ore-Reserve estimates to take account of uncertainties. Whilst methodologies that account for physical uncertainty appear relatively well developed, methodologies which can take account of economic uncertainty appear much less so. To counter this shortfall, we present an efficient and general methodology which can quantify the effect of price uncertainty within reserve estimates, providing both the expected reserve size and the associated distribution (box whisker plot). This statistical information can be used by interested parties to understand precisely where the reserve risks lie, which we highlight in a worked example.  相似文献   

4.
This article analyses the lifetimes of reserves of three dozen important minerals. Despite the high rate of their extraction in the past 30 years, the recorded reserves of these non-renewable materials were higher in 1981 than in 1950 and they seem to meet foreseeable demand for a long time to come, as indicated by the estimated static lifetime for each of the minerals covered. The dynamic nature of ‘reserves’ is emphasized: further exploration and scientific and technological advance will add to the present proven reserves, and at a higher price further resources will be ‘upgraded’ into commercially exploitable reserves. Apparent long-term security can be disturbed by natural disasters, political events or other factors, especially in the case of minerals whose reserves and production are highly concentrated in one country. However, any such interruption in the continuity of supply is likely to be short-lived.  相似文献   

5.
The development of Australia's North-West Shelf gasfield is the largest single private venture yet undertaken in Australia, with expenditure of around A$3000 million. Gas will be exported (primarily to Japan), and there will be local sales, at present confined to the state of Western Australia. Annual revenue is estimated to be A$743 million (in 1977 prices) over the life of the project, with annual tax and royalties rising to A$330 million once loans are repaid. The net effect on Australia's balance of payments is positive in most years. The project's apparent feasibility has provided an impetus to further offshore exploration in the West, with A$400 million now committed.  相似文献   

6.
A quantitative estimate of the petroleum reserves of the Middle East and North Africa is presented and analysed in terms of the region's ability to meet current market demand for a sweet light crude. Costs of Middle East production are compared with those of other oil-producing regions. With an average costs of US$4/bbl, the Middle East has both the largest oil reserves and the lowest cost oil in the world. While new and improved technology of exploration and production may lessen this price advantage in the future, it will not eliminate it. Because of these two factors, the Middle East will continue to play an important role on the world energy stage well into the next century.  相似文献   

7.
Fuzzy assessment of land suitability for scientific research reserves   总被引:1,自引:0,他引:1  
Evaluating the characteristics of a set of sites as potential scientific research reserves is an example of land suitability assessment. Suitability in this case is based upon multiple criteria, many of which can be linguistically imprecise and often incompatible. Fuzzy logic is a useful method for characterizing imprecise suitability criteria and for combining criteria into an overall suitability rating. The Ecosystem Management Decision Support software combined a fuzzy logic knowledge base we developed to represent the assessment problem with a GIS database providing site-specific data for the assessment. Assessment of sites as a potential natural reserve for the new University of California campus at Merced demonstrates the benefits of fuzzy suitability assessment. The study was conducted in three stages of successively smaller assessment regions with increasingly fine spatial resolution and specificity of criteria. Several sites were identified that best satisfy the suitability criteria for a reserve to represent vernal pool habitat.  相似文献   

8.
The quest for sustainable communities might be fostered by a new ‘place-based’ governing approach that engages civil society and other actors in local decision-making processes. In Canada, lessons can be learned from the establishment and maintenance of biosphere reserves by networks of local communities of interests and other organisations. Biosphere reserves are created to promote conservation, biodiversity and sustainable livelihoods. Municipal and public participation in these reserves can be encouraged, promoting a local sense of place as well as sustainable community and regional development. An examination of two Canadian biosphere reserves, Riding Mountain and Long Point, illustrates how local governments and these reserves might assist each other in their mutual goals of long-term sustainability while offering a worthwhile model of local collaborative, place-based governance.  相似文献   

9.
Ecological approaches to drawing boundaries for parks and reserves are developed, described as 15 guidelines. The five abiotic guidelines are designed with the principle objective of maintaining drainage basin integrity. The ten biotic guidelines are designed to reduce as little as possible the natural diversity of populations in both the total natural area and in the communities directly traversed by the boundary line. Three of the biotic guidelines apply to maintaining community diversity, the remainder to species diversity. These guidelines are applied to a 2500-km2 potential national park in a montane environment in the southwest Yukon Territory. They were successful in generating the conclusion that boundaries in the subalpine best satisfy the guidelines in this environment.  相似文献   

10.
Among the many factors that contribute to overexploitation of marine fisheries, the role played by uncertainty is important. This uncertainty includes both the scientific uncertainties related to the resource dynamics or assessments and the uncontrollability of catches. Some recent works advocate for the use of marine reserves as a central element of future stock management. In the present paper, we study the influence of protected areas upon fisheries sustainability through a simple dynamic model integrating non-stochastic harvesting uncertainty and a constraint of safe minimum biomass level. Using the mathematical concept of invariance kernel in a robust and worst-case context, we examine through a formal modeling analysis how marine reserves might guarantee viable fisheries. We also show how sustainability requirement is not necessarily conflicting with optimization of catches. Numerical simulations are provided to illustrate the main findings.  相似文献   

11.
In small populations the lack of mating individuals may cause a reduction in reproductive potential which can restrict population expansion or cause further population declines. This is especially true in outcrossing monoecious and self-incompatible dioecious plant species. Principles of pollen dispersal suggest that many small to medium size population reserves of round shape will maximize the pollen interaction within and between island reserves. Diverse and low-density ecosystems require more total area in reserves than low-diversity and high-density ecosystems.  相似文献   

12.
The establishment of forest reserves for the benefit of other resources and other land uses in areas where timber harvesting is taking place constitutes a significant withdrawal of wood fiber annually in Ontario.This article reports on a case study carried out on a representative forest area in northern Ontario where the primary land use is timber extraction. The results projected to the whole province show that the direct cost to the provincial economy of removing these forest lands from timber production is of the order of $2.5 million annually.  相似文献   

13.
自然资源资产仍然是一个新概念,还需要在理论和方法层面进行系统的研究。就当今及今后一个时期看,自然资源资产负债表的编制和自然资源资产审计,是亟需研究的理论和现实问题。在此,重点对自然资源资产的概念、属性、分类进行探讨,并就自然资源资产负债表及编制的重点与基础,自然资源资产审计及其重点与方式等,进行系统讨论。  相似文献   

14.
China has laid out an ambitious strategy for developing its vast shale gas reserves. This study developed an input–output based hybrid life-cycle inventory model to estimate the energy use, water consumption, and air emissions implications of shale gas infrastructure development in China over the period 2013–2020, including well drilling and operation, land rig and fracturing fleet manufacture, and pipeline construction. Multiple scenarios were analyzed based on different combinations of well development rates, well productivities, and success rates. Results suggest that 700–5100 petajoules (PJ) of primary energy will be required for shale gas infrastructure development, while the net primary energy yield of shale gas production over 2013–2020 was estimated at 1650–7150 PJ, suggesting a favorable energy balance. Associated emissions of CO2e were estimated at 80–580 million metric tons, and were primarily attributable to coal-fired electricity generation, fugitive methane, and flaring of methane during shale gas processing and transmission. Direct water consumption was estimated at 20–720 million metric tons. The largest sources of energy use and emissions for infrastructure development were the metals, mining, non-metal mineral products, and power sectors, which should be the focus of energy efficiency initiatives to reduce the impacts of shale gas infrastructure development moving forward.  相似文献   

15.
Summary Biosphere reserves are protected areas of representative environments internationally recognised for their value for conservation and for their ability to provide the scientific knowledge, skills and human values to support sustainable development. Biosphere reserves — as a part of the UNESCO programme Man and the Biosphere (MAB) — make up a world-wide network sharing research information on ecosystem conservation, management and development. They include strictly protected core-areas — representative examples of natural or minimally disturbed ecosystems. Core areas are surrounded by buffer zones in which research, environmental education and training and recreation can take place. Buffer zones are, in turn, surrounded by transition areas, large open areas where the aim is to ensure rational development of the natural resources of the region. At present, twelve biosphere reserves are designated in Germany, covering in all an area of 11,589 km2. The role of biosphere reserves to support sustainable development in Germany and Europe is discussed.Karl-Heinz Erdmann is a geographer and Deputy Secretary General at the Secretariat of the German National Committee for the UNESCO Programme on Man and Biosphere (MAB), Federal Agency for Nature Conservation. He is also a Committee Member of the Society for Man and Environment (GMU).  相似文献   

16.
《Resources Policy》2005,30(1):55-69
Studies by Nutting, Jacobson and Evans and Georgentalis et al. have all concluded, using panel data sets, that a number of metals appear to share a common demand curve that is stable over time. However, these studies have a number of theoretical and econometric limitations. This paper addresses these concerns and reassesses the hypothesis that some metals share such a common demand curve with the same price elasticity of demand. This is achieved within the framework of a random coefficients model. This model was applied to a dynamic metals demand function (DLR) and various estimation techniques were used including OLS, IV, Empirical Bayes (EB) and Instrumental Variables Empirical Bayes (IV-EB). It was found that each metal had its own individual short run demand function with statistically different own price and industrial activity elasticities of demand. In the long run, each metal appeared to be equally unresponsive to price changes, but had different industrial activity elasticities. The speeds of price adjustment to periods of market disequilibrium differed substantially between metals.  相似文献   

17.
Low wellhead domestic gas prices over the past few years have led to the beginning of a shortage in natural gas reserves and production in Pakistan. Gas demand steadily rises in all sectors for being an economical fuel as compare to substitutes. In the view of foregoing consumption trend, the demand for gas is expected to grow with a higher pace during the 2010s. On the contrary, indigenous gas reserves are running out and cannot keep up with the demand. This paper examines the extent of upstream activities in different petroleum policy regimes. The wellhead price for indigenous gas is compared with the prices of alternatives (for example, gas import prices). In order to put the problem in perspective, the relationship between wellhead gas price and cumulative gas reserves in Pakistan are analyzed and we find that the looming gas shortage can be ameliorated in the short-run and eliminated in the long-run through incentivized wellhead price. To put it briefly, the idea is mooted to first take advantage of huge domestic reserves to ensure competitive consumer prices for gas. The findings are applicable to several other economies with under-developed natural resources.  相似文献   

18.
郁金香花色丰富,应用广泛,是一种重要的观赏植物,现已被利用的郁金香有9种,而未被开发的郁金香资源还很丰富。介绍了36种可开发利用的郁金香资源的形态及分布,以供参考。  相似文献   

19.
本文从国家实施可持续发展战略出发,分析了环境统计工作存在的问题。提出了可持续发展的环境,资源统计与核算的新概念。  相似文献   

20.
Valuation of Ecological Resources and Functions   总被引:8,自引:0,他引:8  
/ Ecological resources are natural resources that provide certain necessary but overlooked system maintenance functions within ecosystems. Environmental economics is in search of an appropriate analysis framework to determine economic values of such resources. This paper presents a framework that estimates and compiles the components of value for a natural ecosystem. The framework begins with the ecological processes involved, which provide functions within the ecosystem and services valued by humans. We discuss the additive or competive nature of these values, and estimate these values through conventional and unconventional techniques. We apply the framework to ecological resources in a shrub-steppe dryland habitat being displaced by development. We first determine which functions and services are mutually exclusive (e.g., farming vs soil stabilization) and which are complementary or products of joint production (e.g., soil stabilization and maintenance of species). We then apply benefit transfer principles with contingent valuation methodology (CVM), travel cost methodology (TCM), and hedonic damage pricing (HDP). Finally, we derive upper-limit values for more difficult-to-value functions through the use of human analogs, which we argue are the most appropriate method of valuation under some circumstances. The highest values of natural shrub-steppe habitat appear to be derived from soil stabilization.KEY WORDS: Natural resource economics; Ecological economics; Ecological resources; Shrub-steppe; Environmental valuation; Cost; Benefit; Value  相似文献   

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