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1.
The US Bureau of Mines has investigated the resource potential of 201 phosphate mines and depositee in 28 market economy countries and 17 mines and deposits in the USSR and China. The 201 mines and deposits contain an estimated 34.2 billiong tonnes (t) of recoverable phosphate rock (at the demonstrated resource level), with Morocco and Western Sahara accounting for 61% (21 billion t) and with the USA accounting for 19% (6.4 billion t). The 17 mines and deposits evaluated in the USSR and China contain approximately 1.5 billion t of potentially recoverable phosphate rock. Potential annual capacity from low-cost, high-grade producing mines in the USA is estimated to decline significantly during the latter half of the next decade, and the US phosphate fertilizer industry will have to obtain phosphate rock by developing new, higher-cost, lower-grade mines or import phosphate rock to satisfy anticipated demand in the next century. Of the world's new production capacity that are likely to be developed over the next decade, slightly over one-third could be produced at an estimated 1981 cost of $40/t or less, and about two-thirds would cost in the $40 to $50 per tonne range (including a 15% rate of return). In comparison, most of the competing phosphate rock from producing mines in Morocco could be produced for less than $40/t.  相似文献   

2.
An important feature of export-oriented production in mineral-rich developing countries for almost three decades after 1960 was the growth of state-owned enterprises. For the phosphate industry, this was reflected in the expansion of companies such as Office Cherifienne des Phosphate (OCP) in Morocco and the Jordan Phosphate Mines Company (JPMC). There was a strategic importance of the industry for these nations and the large capital outlays necessary for phosphate and fertilizer production expansion often required considerable government assistance because of the perceived high risks of private investment in the industry.  相似文献   

3.
The article focuses on fossil energy resources in the Andean Group and Mexico, and argues for a dynamic approach to calculating reserves to production ratios. Individual countries are surveyed in terms of estimated reserves of fossil energy resources, current production rates and future prospects; energy policy options for individual countries are analysed. As a primary objective of energy policy is to ensure security of supply, it is important that calculations of reserves to production ratios accurately estimate the desired level of investment in exploration. The calculations need to take into account a variety of parameters, including different energy sources, availability and risk; geographic considerations including proximity, transport, storage capacity and commercial aspects; the competitive and environmental implications of developing indigenous resources; and the use of instruments to establish contingency plans for emergencies.
The opinions expressed in this article are those of the authors, and do not necessarily reflect the views of OLADE, ECLAC or GTZ. The authors apologize for any inaccuracies or omissions in the article.  相似文献   

4.
The concept of “peak oil” has been explored and debated extensively within the literature. However there has been comparatively little research examining the concept of “peak minerals”, particularly in-depth analyses for individual metals. This paper presents scenarios for mined copper production based upon a detailed assessment of global copper resources and historic mine production. Scenarios for production from major copper deposit types and from individual countries or regions were developed using the Geologic Resources Supply-Demand Model (GeRS-DeMo). These scenarios were extended using cumulative grade-tonnage data, derived from our resource database, to produce estimates of potential rates of copper ore grade decline.The scenarios indicate that there are sufficient identified copper resources to grow mined copper production for at least the next twenty years. The future rate of ore grade decline may be less than has historically been the case, as mined grades are approaching the average resource grade and there is still significant copper endowment in high grade ore bodies. Despite increasing demand for copper as the developing world experiences economic growth, the economic and environmental impacts associated with increased production rates and declining ore grades (particularly those relating to energy consumption, water consumption and greenhouse gas emissions) will present barriers to the continued expansion of the industry. For these reasons peak mined copper production may well be realised during this century.  相似文献   

5.
This article focuses on changes in the international petroleum industry during the past 20 years and examines some major trends, especially since the oil price collapse of 1986. The resumption of rapid increases in oil demand since 1986 in the developed market economies and the developing world has already led to a pronounced production shift to OPEC member countries where output increased by 6.6 million barrels per day or, 37% since 1985. Cutbacks in petroleum investments in non-OPEC countries are likely to result in even more dependence on the vast proved oil reserves of OPEC. However, the gap between peak output and sustainable production capacities in OPEC has narrowed and there is an urgent need for sizeable investments to expand capacities. Such investment programmes are already being implemented by transnational oil corporations in countries such as Indonesia and Nigeria where the companies had retained equity participation. In other countries such as Iraq and Venezuela where oil operations had been nationalized, transnational oil corporations are being invited to participate in new arrangements for oil production. New arrangements are also being considered in Eastern Europe and the USSR. New understandings, dialogue and cooperation between oil-consuming and producing countries will be necessary for the security of investments, supplies and markets in this process. The unanswered question is whether such cooperation can be achieved in time in order to avoid yet another energy crisis.  相似文献   

6.
The problems and prospects of solar and wind energy technologies for rural energy supply in developing countries are examined, followed by an overview of key attributes of these technologies. The application of wind and solar systems for cooking, water pumping, drying, water heating, and electric power supply are reviewed. Two detailed case studies are given, the first discussing the potential of solar and wind systems for rural water pumping in Morocco, and the second, examining the "wind farms" producing electric power in California and the potential for their use in developing countries.  相似文献   

7.
The magnitude of the ‘economic rent’ and its distribution among producing countries, mineral exploitation companies and consumers has become a dominant issue in national and international policy formulation, but the difficulties in measuring the rent add to the problems of determining its equitable distribution. This paper examines the nature of the rent and estimates its incidence in bauxite, copper, iron ore, phosphate rock, tin and petroleum. Rents were found to be low for bauxite and iron ore. Bauxite, phosphates and petroleum producers have increased their share of the rent, though this trend now seems to be reversing for bauxite and phosphates. Only in tin, and to a lesser extent petroleum, have the exporting countries captured significant shares in total rent. Otherwise, the rent is largely concentrated at the processing stage, which suggests that processing plant would have to shift to the producing countries if they are to claim a larger share.  相似文献   

8.
This paper reviews a recent assessment of fluorspar reserves and resources for 13 market economy countries and the People's Republic of China, and how they relate to the overall availability of fluorspar on the world market. Current world production, consumption and world trade issues are discussed.
Nearly 5 million tonnes of fluorspar were produced in 1985, and approximately 60% of that enters the world export market. In recent years world trade has started to shift away from the acid, metallurgical and ceramic grades of fluorspar, as ore-producing countries look towards higher-value downstream products.
Total potentially recoverable fluorspar from 52 major producing mines and deposits is estimated at nearly 95 million tonnes (as of January 1985). The Republic of South Africa accounts for 31% of the reserves, with Mexico and the People's Republic of China each contributing 18%.
The average total cost and availability of fluorspar is evaluated. Approximately 75% of acid-grade fluorspar evaluated is potentially available at or below a 1985 constant-dollar cost of US$110 tonne−1. Nearly 94% of metallurgical grades are potentially available at costs of US$75 tonne−1 and below, and virtually all of the ceramic grades could be produced at costs below the 1985 reported market price of US$103 tonne−1.  相似文献   

9.
The major countries consuming metals tended historically to be also the major countries producing them. It was in their interest to promote mine development to provide low cost raw materials. Over the past fifty years, the share of global production accounted for by consuming countries has declined and producers and consumers of metals have been slowly moving into separate camps having distinct and differing interests. As a consequence of this, governments of producing countries have become more focused on how to maximise the benefit of metal extraction to their economies rather than on how to supply cheap raw materials; a tendency which has found expression in resource nationalism. Governments of consuming countries have in response become increasingly concerned about the implications of this tendency to their economic development and some countries, most notably China, have adopted robust policies to secure their supplies. Through their actions to influence capital flows within the mining industry and to force metals trade into channels which better serve their national interests (a process characterised here as ‘new mercantilism’), metal producing and metal consuming countries are reshaping global supply.  相似文献   

10.
以加权平均抛物线拟合法为例,研究了顾及后期地形曲线光滑模型的采样点布设规则的确定问题.研究表明,对需要光滑拟合处理的地形曲线,除了传统的适当增加冗余采样点(采集质量检测点)外,还需要依据后期的光滑拟合模型,合理规划这些检测点的布点位置,才能有效保障地形曲线的科学采样与高保真重构.  相似文献   

11.
The Bureau of Mines investigated the resources, costs, capacities, market relationships, and short- and long-run supply of phosphate rock and phosphoric acid. The 206 mines and deposits evaluated in 30 market economy countries (MECs) contain an estimated 35.1 billion tonnes of recoverable phosphate rock (demonstrated resource level). US resources are sufficient to satisfy both the domestic market and an export market for phosphate products well beyond 2000. Resource depletion at current producers, however, means new property development (with higher costs) will be required if US production levels are to be maintained. Existing worldwide capacity can satisfy expected demand through the early 1990s. Expansion at existing mines or low demand growth could mean no new property development is required before the late 1990s. Worldwide, almost $8 billion could be required for the development of new phosphate rock properties between now and 2000, given 3% annual growth in demand. Though profit may not be the principal motivation for development of government-owned operations, most properties that could develop in the 1990s would require price increases of 20–50% to break even. To earn a 15% rate of return on investment, prices must rise to nearly double the $23–271 tonne US price level of 1988. Current US phosphate rock and phosphoric acid producers appear to be competitive (on a variable cost basis) with many other suppliers in major markets. New US properties will have higher variable costs than current producers; however, they are competitive with most projected new foreign development. The US phosphoric acid industry will most likely face increased competition as more of the foreign phosphate rock producers develop the capacity to process rock into phosphoric acid and other fertilizer products.  相似文献   

12.
Ocean acidification (OA) is increasingly recognized as a major global problem. Despite the scientific evidence, economic assessments of its effects are few. This analysis is an attempt to perform a national and sub-national assessment of the economic impact of OA on mollusc production in Europe. We focus on mollusc production because the scientific evidence on the biological impact on calcifying organisms is ample relative to other types of marine organisms. In addition, Europe and its regions are significant producers of marine molluscs. By performing a partial-equilibrium analysis, we show that the highest levels of overall impact are found in the countries with the largest current production, such as France, Italy and Spain. For Europe as a whole, the annual impact will be over 1 billion USD in 2100. Due to the different production foci of the individual countries and their regions, the distribution of the impact is extremely uneven across countries and their respective regions, with the most affected sub-national regions being those on the Atlantic coast of France, which is an important region for oyster production.  相似文献   

13.
This review analyses some of the environmental and economic implications of current trade policies and changes in the world trading system for mineral producers and consumers. A principal factor which determines environmental performance is whether firms have the resources and capabilities to undertake innovation. We therefore place particular emphasis on the anticipated effects of liberalized trade on innovation and competitiveness at the firm level. Evidence indicates that improvements in environmental management would be expected to occur irrespective of the country hosting the investment. Due to the opening investment climate and relatively large quantities of mineral reserves, we expect these effects to be positive for many mineral producing developing countries. One difficulty which may arise is whether policy measures to promote production efficiency and develop innovation in mining and mineral processing operations could be interpreted as protectionism. The creation of new lines of credit, to promote, but not subsidize, technological and organizational innovation, may be the best way forward for developing countries .  相似文献   

14.
杨小宁  郭靓  但德忠 《四川环境》2007,26(6):49-53,68
通过对环境样品分析中常用的色谱分析法测量不确定度分量来源及影响的讨论,探讨了色谱分析法测量不确定度的评估方法,获得了针对不同环境基体样品、不同测定组分以及不同前处理方法中的扩展不确定度。色谱分析中的测量不确定度主要来源于流速稳定性、柱箱温度稳定性、基线噪声、程序升温重复性、定量重复性、标准物质进样量及由峰面积通过标准曲线拟合求浓度等部分。  相似文献   

15.
Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively. The beneficial effects of the microbial organic fertilizer are discussed. Justification for more intensive research on rock phosphate organic fertilizer is highlighted.  相似文献   

16.
Methane fluxes from artificial wetlands: A global appraisal   总被引:1,自引:0,他引:1  
Methane emissions make an important contribution to the enhanced greenhouse effect, emissions from rice growing being one of its major anthropogenic sources. The estimation of global fluxes of methane from rice and from coarse fiber production depends on extrapolating observed data across countries and agroclimatic zones: the estimates are therefore imprecise. We present a revised estimate of global emissions of 96 Tg CH4/yr, given 1991 rice areas, and 1991 production data for those tropical coarse fibers that also produce methane under anaerobic conditions. This is higher than many previous studies, which systematically underestimated the fluxes from tropical countries. As the world's population increases, the demand for rice will rise. This demand can only be satisfied through greater rice production, either by bringing new areas into rice growing or by using the present area more intensively. Strategies based on improved water management and fertilizer use will allow increased rice production and yields and reduce the methane flux per unit or rice production.  相似文献   

17.
Interest in substituting reproducible inputs such as capital and labour for non-renewable materials is principally motivated by two factors — the short-run concern about supply disruptions on the part of producing countries and the long-run concern about the exhaustion of depletable natural resources. In this paper, techniques for estimating elasticities of substitution between inputs (ie between different materials or between material aggregates and other input aggregates) from production and cost functions are discussed, and the recent literature that makes use of these techniques is reviewed.  相似文献   

18.
The importance of sustainable consumption and production in the international agenda has been growing, both because of unsustainable patterns of consumption and production in industrialized countries and because it appears to be a means for meeting the essential needs of developing countries. Adapting Fernand Braudel's model of the three layers of the economy (everyday life, market economy and global capitalism) to the current situation, this paper advocates for differentiated policies, which cannot be limited to those based on the dominant model of a rational legal system dealing with rational consumers. The cultural and collective dimensions of consumption, the social role of conspicuous consumption, the consumption of ecological services outside formal markets, the diversity of approaches to knowledge and rationality, all plead for an overarching approach and diversified policy tools. The paper underlines the need for global regulation processes which involve all stakeholders by focusing on two examples: the international task force on sustainable tourism, and the ISO 26000 standard on social responsibility.  相似文献   

19.
Irrigation water management is crucial for agricultural production and livelihood security in Morocco as in many other parts of the world. For the implementation of an effective water management, knowledge about farmers' demand for irrigation water is crucial to assess reactions to water pricing policy, to establish a cost-benefit analysis of water supply investments or to determine the optimal water allocation between different users. Previously used econometric methods providing this information often have prohibitive data requirements. In this paper, the Contingent Valuation Method (CVM) is adjusted to derive a demand function for irrigation water along farmers' willingness to pay for one additional unit of surface water or groundwater. An application in the Middle Draa Valley in Morocco shows that the method provides reasonable results in an environment with limited data availability. For analysing the censored survey data, the Least Absolute Deviation estimator was found to be a more suitable alternative to the Tobit model as errors are heteroscedastic and non-normally distributed. The adjusted CVM to derive demand functions is especially attractive for water scarce countries under limited data availability.  相似文献   

20.
ABSTRACT: The unit hydrograph is a common tool in hydraulic design. Used correctly, it allows a design engineer to estimate a runoff hydrograph from a drainage basin given a rainfall event. The typical method for estimating a unit hydrograph for a gaged watershed is by deconvolution. However, distinct storms produce different unit hydrographs for a single watershed. Consequently, a design engineer usually develops a composite, or average, unit hydrograph based on several recorded storm events. Common methods for estimating this composite unit hydrograph include curve fitting, simple aggregation, and multistorm optimization techniques. This paper introduces a new method to perform aggregation of unit hydrographs. The method is an extension to the simple averaging technique, in which prior to averaging, the individual unit hydrograph time ordinates are normalized with respect to the average time to peak. The normalization method is compared to a simple averaging technique and two multistorm aggregation techniques at six rural watersheds in Alabama. The results indicate that on average the normalization method predicts runoff nearly as accurately as the multistorm techniques, and displays improvement for 60 percent of the storms tested when compared with the simple averaging technique.  相似文献   

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