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891.
This paper describes how the Carajas iron ore project was set up in February 1985 at a time of deep recession in the iron ore and steel industries. Development of the project was met with much criticism, mainly from North American steel makers, who argued that the project would only be successful through the support of a Third World government, highly dependent on foreign exchange, without any consideration being given to its economic feasibility or to the fundamentals of the market. The authors explain why the World Bank took the step of setting up the project and how its development can be partly explained by the interests of the Japanese and European steel makers. The role of the Brazilian government is explained and the authors conclude that the relatively low rate of investment anticipated by the project will be overshadowed by the high gains in foreign exchange. 相似文献
892.
R. C. Kattelmann N. H. Berg M. K. Pack 《Journal of the American Water Resources Association》1985,21(2):273-280
A simple simulation model designed to monitor snow-packs of the central Sierra Nevada is described. The model estimates average snow water equivalent for rectangular subregions in the area. Static subregion characteristics, daily precipitation and mean and minimum air temperatures measured at three index stations are the only needed input values. A water balance technique simulates daily snowpack changes in each subregion. Reasonable basinwide water equivalent values are produced. The procedure should be useful for estimating snow water distribution in large mountainous watersheds. 相似文献
893.
Peter Wathern Stephen N. Young Ian W. Brown Dawn A. Roberts 《Environmental management》1987,11(1):7-12
The EEC Shellfish Directive is a policy designed to protect and, where necessary, improve the quality of designated shellfish waters. Its implementation within the UK, however, has had no effect upon water quality for two reasons. First, the policy has important defects, having ambiguities concerning public health provisions and lacking designation criteria. Second, UK government has sought to achieve formal compliance, while at the same time ensuring that its full financial impact on public expenditure has been contained. Consequently, only those fisheries which already comply with water quality standards have been designated. Within Wales, one fishery has been designated, while other, commercially more important, but grossly contaminated shellfisheries have not. 相似文献
894.
Recreational impacts on backcountry campsites in Grand Canyon National Park,Arizona, USA 总被引:2,自引:0,他引:2
Backcountry campsites were studied in three desert vegetation types (pinyon-juniper, catclaw, and desert scrub) in Grand Canyon National Park, Arizona. Relationships between amount of use and amount of impact were examined within each vegetation type. The area disturbed was small, but impacts were generally severe. Important impacts were increased soil compaction and associated decreases in infiltration rates and soil moisture content; these were substantially more pronounced on high than low use sites. The only impact parameter that differed significantly between vegetation types was core area. The types of impact identified are similar to those found in the coniferous forests studied elsewhere, as is the logarithmic relationship between amount of use and amount of impact. However, Grand Canyon sites can support more visitor use before reaching near-maximum levels of impact for important impact parameters. 相似文献
895.
B. BOWONDER Chairman S. S. R. PRASAD Project Associate N. V. M. UNNI Head 《Natural resources forum》1986,10(1):5-16
The price of fuelwood has been increasing at a rate higher than that of the consumer price index in most of the major urban centres of India. Today, in terms of cost per unit of energy delivered, fuelwood is more than twice as expensive as kerosene for cooking. This has immense public policy implications. A number of complementary policy interventions are needed so that forests can be saved and the stability of energy supplies can be achieved in developing countries. 相似文献
896.
Three hundred and three biogas plants, representing a majority of the units installed in Sri Lanka up to 1984, were inspected, and it was found that 280 of these had been put into commission at some time prior to the study. Of the 280 commissioned plants, 170 (61%) were functioning satisfactorily providing biogas for cooking and/or lighting. The remaining 110 (39%) were either not functioning or were supplying very little gas owing to gas leaks, inadequate input of dung, or poor plant management. The most common plant was the 6 m3 , fixed dome, household plant, and the most common raw material used was cattle dung. In the majority of household plants the cost of construction was partly or wholly subsidized. 相似文献
897.
Summary In the present paper efforts have been made to identify an environmentally sustainable and economically gainful strategy for agricultural development in the Himalayan region in Uttar Pradesh State, India. In the underdeveloped rural habitat that exists, a strategy, where the economics of environmentally sustainable development can be studied, is urgently required. The findings have been based on an empirical investigation of 150 sampled households spread over fifteen villages. It was found that the state of Himalayan agriculture and allied activities was in a critical condition, requiring urgent attention in order to improve the human environment. Suggested viable improvements in Himalayan agricultural development may be grouped into four categories, viz., an expansion of the cultivated area, where the land use pattern and other factors are discussed; full utilisation of irrigation potentialities, in which water management is discussed; improvement in the cropping pattern, where the whole system of cropping is analysed; and modifications in the use of agricultural appliances, specially in hoeing, ploughing and inter-culturing implements. Based on a critical analysis of these four identified aspects, economically viable, ecologically sound and socially justified environmental planning may be effectively framed.Dr H.C. Pokhriyal is Head of the Department of Economics at Garhwal University Campus, Tehri, and Dr N.S. Bist is Professor and Head of the Department of Economics at Garhwal University, Srinagar Garhwal, Himalaya, U.P., India. 相似文献
898.
899.
Paul N. Wilson Teddy J. Goldammer James C. Wade 《Journal of the American Water Resources Association》1988,24(1):1-9
ABSTRACT: Urban wastewater can be a valuable source of water and plant nutrients for agricultural producers, particularly in arid regions. The scientific literature reveals cautious optimism concerning the biological, institutional, and economic viability of irrigating crops with secondary-treated effluent. A derived effluent demand function for agricultural producers near Tucson, Arizona, reveals a potential annual demand of 11,000 acre-feet under present price and proposed delivery system conditions. In this case, wastewater could be exchanged for ground water and both the urban and rural areas would gain. 相似文献
900.
Everett M. White James N. Dornbush 《Journal of the American Water Resources Association》1988,24(2):269-273
ABSTRACT: Wastewater from a municipal treatment plant was applied in rapid infiltration basins for four years to determine a poorly drained soils effectiveness in removing influent N and P and the soil changes that might limit their removal. About half the total PO4-P lost from the influent was sorbed in the upper 91 cm of the soil and the other half was sorbed by the soil below the perforated pipe, which was used to drain the basins and collect the effluent for analysis. Drying of the basin soils converted more sorbed PO4-P to Ca phosphates but the total sorbed was about the same. The in. fluent N decreased, probably by volatilization, because the two basins with surface soil lost soil N rather than gained soil N. The soil total Ca, Mg, and K contents did not change significantly but Na increased slightly. Changes in the physical characteristics of the soils were slight and would have little effect on the longevity of a rapid infiltration basin. 相似文献