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1.
In 1982, for the first time since OPEC was founded in 1961, its production was surpassed by the non-OPEC countries in the world excluding the centrally planned economies. In that year, for the world as a whole, OPEC provided 35% of the oil consumed. The decline was brought about by a decrease in consumption and by a marked increase in production from non-OPEC sources. It is expected that non-OPEC producers will have the capacity to meet more than half of the world's oil requirements until the early 1990s, at which time OPEC producers will again assume the role of providing over 50% of the world's oil.  相似文献   

2.
The US Department of Interior, Bureau of Mines has evaluated the potential resource and annual availability of cobalt from 27 deposits or districts in 11 market economy countries. More than 90% of primary cobalt production from market economy countries, mainly by-product output from copper and nickel operations, was analysed. The producing operations evaluated in this study were expected to produce about 19 000 t of cobalt in 1989, significantly less than the available capacity of 31 000 t. Approximately 1200 000 t of cobalt is potentially recoverable at the demonstrated resource level. Very large additional resources exist, especially in laterite deposits, but are at the inferred level.  相似文献   

3.
Aquatic ecosystems are vital to the structure and function of all environments on earth. Worldwide, approximately 95 million metric tons of fishery products are harvested from marine and freshwater habitats. A major problem in fisheries around the world is the bioethics of overfishing. A wide range of management techniques exists for fishery, managers and policy-makers to improve fishery production in the future. The best approach to limit overfishing is to have an effective, federally regulated fishery, based on environmental standards and fishery carrying capacity. Soon, overfishing is more likely to cause fish scarcity than fossil fuel shortages and high energy prices for fish harvesting. However, oil and other fuel shortages are projected to influence future fishery policies and the productive capacity of the fishery industry. Overall, small-scale fishing systems are more energy efficient than large-scale systems. Aquaculture is not the solution to wild fishery production. The energy input/output ratio of aquacultural fish is much higher than that of the harvest of wild populations. In addition, the energy ratios for aquaculture systems are higher than those for most livestock systems.  相似文献   

4.
This paper discusses how world steel production and seaborne iron ore trade have grown since 1950. The role of steel production forecasts in determining investment in the iron ore industry is examined. Forecasts for world steel production and the demand and supply of seaborne iron ore in the 1990s are presented. It is predicted that world steel production will increase by 64 million tons between 1991 and 2000. This increase will be located principally in the developing countries and China. The corresponding increase in seaborne iron ore trade will be approximately 55 million tons. Expansion projects will be located mainly in Australia and Brazil, but no greenfield iron ore projects will be undertaken. By the end of the decade, the demand for seaborne iron ore will be equal to its supply.  相似文献   

5.
This paper examines the evolution of the control by the state of mining and smelting from 1975 to 1989. In 1950, there was little state-owned mining capacity outside the centrally planned economies. A wave of nationalizations of mine assets swept over the developing countries in the late 1960s and early 1970s. State control continued to rise, in developing countries as well as in the developed market economy countries, until the mid-1980s, when the trend reversed. At present some 20% of Western world mineral production is state controlled. The level of control is highest for those minerals mined mainly in the developing countries, and lowest for those minerals mined mainly in the developed market economy countries. The current trend is toward privatization of state-owned mining enterprises in developed countries and it is expected that as the 1990s progress, privatization of such enterprises will also begin to take place in developing countries.  相似文献   

6.
7.
Gold mining is the major economic activity in the Upper Tapajós River Basin of the Brazilian Amazon. This article studies the structure, economy and impacts of gold mining operations in this region. Mining has significant environmental impacts in this region resulting in the removal of approximately 67 million m3 of sub-soil per year and accompanied by an annual release of some 12 tons of mercury to air, ground and rivers. In the early 1990s there were 245 mines in operation, employing some 30000 people and producing around 35t gold per year, valued at approximately $400 million yr-1, the profits being about $110 million yr-1. Miners spent most of their earnings on local goods and services, while mine owners and merchants in the gold towns invested in land (mainly for ranching), business ventures and money markets. Wealth gained from mining has served as an engine for development in other regions of the world and could, theoretically, achieve the same for Amazonia. However, before this could happen, the Government of Brazil would need to mark a strong presence in the area by providing technical assistance and developing and enforcing mining/environmental regulations. The likelihood of such a development materializing in the foreseeable future is small. In the meantime, gold mining acts, not as an 'engine for development', but as a destabilizing force — provoking environmental damage, social discord and public health hazards in the region.  相似文献   

8.
Increasing levels of household waste have raced up national, regional and municipal environmental policy agendas around the world, especially as heavy reliance on landfill and incineration is becoming prohibitively expensive and also a high profile source of local voter dissent or vociferous NIMBY behaviour. In an attempt to reduce reliance on these options, UK local authorities have increasingly been forced to turn to recycling. This paper reports on a broad empirical study of household recycling, utilizing national survey-based evidence (drawn from over 31 000 interviews in Scotland). Hitherto, very few published empirical studies have addressed the household recycling decision using national survey data to furnish baseline evidence. For this purpose logit analysis is undertaken, using data extracted from the Scottish Household Surveys of 2000 and 2001. This work also serves as the basis for further detailed modelling of a selection of illustrative household types. After consideration of particular waste streams and the availability of different recycling schemes, the effects on the probability of recycling participation of age, income level, household composition, car ownership and local authority were analysed. While there are clear income effects, the picture regarding the impact of household composition and some other factors is more complex.  相似文献   

9.
Waste accumulation is a grave concern and becoming a transboundary challenge for environment. During Covid-19 pandemic, diverse type of waste were collected due to different practices employed in order to fight back the transmission rate of the virus. Covid-19 was proved to be capricious catastrophe of this 20th century and even not completely eradicated from the world. The havoc created by this imperceptible quick witted, pleomorphic deadly virus can't be ignored. Though a number of vaccines have been developed by the scientists but there is a fear of getting this virus again in our life. Medical studies prove that immunity drinks will help to reduce its reoccurrences. Coconut water is widely used among all drinks available globally. Its massive consumption created an incalculable pile of green coconut shells around the different corners of the world. This practice generating enormous problem of space acquisition for the environment. Both the environment and public health will benefit from an evaluation of quantity of coconut waste that is being thrown and its potential to generate value added products. With this context, present article has been planned to study different aspects like, coconut waste generation, its biological properties and environmental hazards associated with its accumulation. Additionally, this review illustrates, green technologies for production of different value added products from coconut waste.  相似文献   

10.
Every year 90 million tonnes of housed livestock manures are produced in the UK. This is a valuable reservoir of global phosphorus (P) and a point in the cycle where it is vulnerable to being lost from the terrestrial system. Improved manure management for the effective reuse of phosphorus is vital to simultaneously tackle a major source of water pollution and reduce our dependence on imported fertilisers. This paper quantifies, for the first time, the spatial and temporal challenges of recycling the required amount of manure P from areas of livestock production to areas of crop production in eight regions of England. The analysis shows that England has a P deficit and therefore the capacity to fully utilise the manure P on arable land, but that uneven spatial distribution of livestock poses a significant challenge to closing the P loop in agriculture. Two of the eight regions were shown to have surplus manure P, with the remaining six regions having P deficits, indicating that an annual export of 4.7 thousand tonnes P (2.8 million tonnes manure) must take place from the west to the east of the country each year to balance P supply and demand. Moreover, housed manure production peaks between October and February, requiring an excess of 23.0 thousand tonnes P (15 million tonnes manure) to be stored until it can be used for crop fertilisation from March onwards. The results demonstrate the scale of the challenge in managing manure P in an agricultural system that has separated livestock production from crop production, a pattern that is echoed throughout the developed world. To overcome the spatial and temporal challenges, a logistical system is recommended that will balance the nutrient potential (nitrogen and P content and availability) and pollution potential (eutrophication, greenhouse gas emissions, particulates and nitrous oxide from transport) for cost-effective and environmentally compatible redistribution of manure P from areas of surplus to areas of deficit, when required.  相似文献   

11.
A method is presented here by which the actual numbers of individuals in the U.S. population who would be expected to suffer respiratory illness as a result of exposure to ambient nitrogen dioxide (NO2) concentrations in excess of the Federally-designated ambient air quality standard can be estimated. At the same time we have attempted to quantify how these adverse health effects would be alleviated by various degrees of reductions in current ambient concentrations. In addition, the health benefit expected to be derived by various NOx emission control strategies will be examined utilizing the health benefit estimation method presented.It is estimated that there were approximately 33.2×106 excess cases of respiratory illnesses in the U.S. in 1973 associated with ambient NO2 concentrations in excess of the national ambient standard. A reduction of approximately 50 to 60 percent below 1973 NO2 levels is needed to essentially eliminate excess respiratory illness associated with ambient NO2 concentration.  相似文献   

12.
Food is a basic human need and therefore a basic human right. While food output has increased to a level where there is enough food produced to feed the world, still millions starve. Using the concept of capitalist world economy as a framework, this paper provides a structural analysis of the food production and distribution system within monopoly capitalism and its implications for countries of the underdeveloped world. Focusing on the impact of a dominant world food supply system on indigenous systems (particularly through the rise of science, technology, and monopoly capital), considerations relating to environmental use and food production and distribution are raised. Finally a call is made for a new agricultural ethic.  相似文献   

13.
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   

14.
ABSTRACT: The current increase in the demand for water by municipal, industrial, and other users is likely to result in approximately one-third less water being available for agricultural use in Texas by the year 2000. As water supplies diminish, the rainfall excess needs to be used more efficiently. Large amounts of runoff occur in the eastern part of Texas that could be collected in small impoundments and utilized for crop production. Farmers in water-surplus basins or subbasins can apply for a permit to divert surface water into small on-farm impoundments to be used for supplemental irrigation. The costs for runoff collection and two supplemental irrigations, which amount to a total of 4 in./yr., are estimated to be approximately $60/acre/year. Depending upon the crop produced, the estimated increase in gross income from supplemental irrigation ranges from about $80 to more than $100 per acre annually.  相似文献   

15.
In the current study, the potential of forest-based biomass supply for the pellet production in Nepal is investigated. This study showed that about 2.76 million tonnes (Mt) biomass in the form of pellets are potentially available from forest-based biomass. Considering a processing capacity of 6 tonnes (t)/hr of a pellet plant, the production cost of the pellets was calculated to be $43.53/t. Pellets are generally used as fuel to produce thermal energy in industries, which helps to save the economy and the environment of the country.  相似文献   

16.
ABSTRACT: Water samples collected from 14 underground coal mines in Colorado were analyzed for major dissolved constituents. The data indicate the water quality of 13 of the samples has developed by the interaction of calcite saturated ground water with sodium rich marine shales. Those samples that displayed evidence of being most completely reacted were composed almost entirely of sodium and bicarbonate ions and had a calcium to sodium activity ratio of 0.16, similar to that of seawater. The one sample that was not saturated with respect to calcite was saturated with respect to gypsum. The dissolved solids concentration attainable by dissolution of gypsum is much less than that attainable by the calcite marine shale equilibration, or approximately 2,500 milligrams per liter. By considering the maximum predicted concentrations of dissolved solids in relation to promulgated water quality criteria, it is possible to predict the hazards of reuse of this mine drainage. The primary problems would be damage or destruction of crops if the drainage water was used for irrigation. In addition, some samples contained concentrations of chloride and sulfate in excess of recommended standards for public water supplies.  相似文献   

17.
This article brings to light one aspect of alternative agri-food practices by exploring the values and meanings domestic food producers associate with their actions, thereby making a small contribution to increasing understanding of the act of urban backyard food production. While Australian backyards have long been productive spaces, there has been little examination of this phenomenon in the Australian context. Limited quantitative data give some insight into the extent of domestic production, and while there is an increasing interest in certain aspects of the local food system, including community gardens and farmers markets, there is a dearth of literature that explores the contemporary act of domestic production. This work seeks to situate the act of domestic production within the broader movement calling for change within the global food system, particularly that being articulated by the food sovereignty movement. Drawing on Gibson–Graham's diverse economies framework, and through interviews with eight domestic food producers in one Australian city, this work finds that the act of growing food at home offers space for hope – where small acts can be seen as part of the broader food sovereignty movement seeking to remake our food system.  相似文献   

18.
There is no agreement as to the definition of a small-scale mine. It is proposed that for a developing country a small-scale mine be defined as a producer (often sporadically) of limited amounts of minerals for deposits with a few known ore reserves, and of a character not readily amenable to mass mining. Output is won without appreciable use of mechanical energy and by exploitation of labor under leadership which sometimes lacks technical, managerial or entrepreneurial skills. A mine producing less than 100 000 tons of ore is considered to be a small-scale mine. Using these criteria and worldwide production data, an estimate of the contribution of small-scale mining to world mineral output is made. The estimate is 16%.  相似文献   

19.
在环境保护意识已经渗透到地球村每个角落的今天,我国科研成果转化率低的问题在环保领域也成为一个“瓶颈”问题。借鉴发达国家成功的经验,在环保领域运用市场化体制建立信息、资本、交易、政策法规等发展平台,对提高环保技术成果转化具有十分重要的现实意义。  相似文献   

20.
Two wellfields have been developed to provide water for a coal fired electric generating station in Arizona. Wellfield No. 1 penetrates the unconfined Coconino Sandstone aquifer, and wellfield No. 2 penetrates the composite Kaibab Limestone-Coconino Sandstone aquifer where ground water occurs under confined conditions. A well in each wellfield was pumped and water level drawdown data were collected before and after acidizing. The drawdown data at the various pumping rates were analyzed to determine the potential benefits of acidizing production water wells in both wellfields. After acidizing, the specific capacity of the well in wellfield No. 1 was improved about 50 percent at water production rates ranging from about 200 to 500 gallons per minute (gpm) (13 to 32 liters per second (lps)). After acidizing, the specific capacity of the well completed in wellfield No. 2 was improved about 100 percent at pumping rates ranging from about 1,250 to 2,200 gpm (79 to 139 lps). An annual saving of approximately 11 percent in pumping costs can be realized in wellfield No. 2, and savings are approximately four percent in wellfield No. 1. Acidization is beneficial for wells that can produce more than 500 gpm (32 lps), and is of marginal value for those that produce less than that amount.  相似文献   

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