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101.
The resource curse   总被引:7,自引:0,他引:7  
Countries that possess rich mineral deposits, it is widely assumed, are fortunate. Such deposits are assets, part of a country's natural capital. Mining is the key that converts dormant mineral wealth into schools, homes, ports, and other forms of capital that directly contribute to economic development. Over the past two decades, however, a more negative view of mining has emerged that questions the positive relationship between mineral extraction and economic development. The impetus for the alternative view came from empirical studies suggesting that countries where mining is important have not grown as rapidly as other countries. More recent studies have explored the possible reasons behind the disappointing performance of many mineral producing countries. While the central point of contention between the conventional and alternative views — namely, whether or not mining usually promotes economic development — remains unresolved, there is widespread agreement that rich mineral deposits provide developing countries with opportunities, which in some instances have been used wisely to promote development, and in other instances have been misused, hurting development. The consensus on this issue is important, for it means that one uniform policy toward all mining in the developing world is not desirable, despite the recent suggestions by some to the contrary. The appropriate public policy question is not should we or should we not promote mining in the developing countries, but rather where should we encourage it and how can we ensure that it contributes as much as possible to economic development and poverty alleviation.  相似文献   
102.
A resource depletion index can serve as a quantitative tool to evaluate the level of depletion for natural resources. This study introduces two types of resource depletion indices, the global resource depletion index and the local resource depletion index. Global resource depletion index mainly concerns global reserves and the annual consumption rate of these resources. The local resource depletion index not only considers global reserves and their annual consumption rate, but also considers the local factors such as local reserves, local recycling rates, and local resource import characteristics. This study considers the local resource characteristics of Taiwan and develops calculations for local resource depletion indexes for the resources of cobalt, molybdenum, tungsten, copper, aluminum, lead and zinc.  相似文献   
103.
ABSTRACT: The uneven temporal and spatial distribution of water on the Earth suggests an important role for the portion of the resource that is not directly used by humans. By extension, an important underlying theory about world-wide resource distribution and function is inferred. Policies that control resource preservation and development need to take this theory into account. Some examples for the water resource are presented.  相似文献   
104.
In 1991, provisions for environmental impact assessment in New Zealand were changed significantly with the enactment of the Resource Management Act. Among other provisions, this act requires consideration of cumulative impacts in environmental assessment activities undertaken by planners in newly created regional authorities and district and city councils. The institutional context in which the act is being implemented offers both opportunities and constraints to cumulative impact assessment. A lack of methods for CIA is a recognized problem. However, methods that have been developed for environmental impact assessments can be modified to incorporate second-, third-, and fourth-order impacts as well as to identify the direction and magnitude of additive and synergistic impacts. Layered matrices and combined networks are examples of such methods. While they do not allow for scientific prediction, they do provide the practitioner with the ability to consider the cumulative impacts of decisions. This is crucial in New Zealand, where statutory requirements are ahead of established methodologies.  相似文献   
105.
The purpose of this research was to elicit and compare the open-space preferences of citizens and openspace experts in Albuquerque, New Mexico, USA. A randomly selected sample of 492 citizens and 35 open-space experts participated in a telephone survey during May 5–18, 1986. The following hypothesis was tested and used as a guideline for the study:HO1: There is no significant difference between respondents' status and preference for open space in Albuquerque, New Mexico.The hypothesis was rejected. Findings confirmed respondents' status affected preference for open space. Of the eight issues on which the citizen and expert groups were compared, five recorded significant differences in response profiles. The open-space expert group was significantly more supportive of using open space to accommodate offroad vehicle facilities, wildlife preserves, a citywide recreational trail, and a trail system along the arroyos and city ditches. The citizen sample was significantly more supportive of using open space to accommodate overnight camping facilities. Both groups equally supported using open space to accommodate an outdoor amphitheater, outdoor education facilities, and rafting, kayaking, and canoeing facilities.The finding indicated that expert preferences did not represent an aggregate of citizen preferences for managing open-space resources. Understanding both expert and citizen positions will facilitate decision-making processes and help resolve environmental disputes.  相似文献   
106.
Energy economy of salmon aquaculture in the Baltic sea   总被引:1,自引:0,他引:1  
Resource utilization in Atlantic salmon aquaculture in the Baltic Sea was investigated by means of an energy analysis. A comparison was made between cage farming and sea ranching enterprises each with yearly yields of 40 t of Atlantic salmon. A variety of sea ranching options were evaluated, including (a) conventional ranching, (b) ranching employing a delayed release to the sea of young smolts, (c) harvesting salmon both by offshore fishing fleets and as they return to coastal areas, and (d) when offshore fishing is banned, harvesting salmon only as they return to coastal areas where released. Inputs both from natural ecosystems (i.e., fish consumed by ranched salmon while in the sea and raw materials used for producing dry food pellets) and from the economy (i.e., fossil fuels and energy embodied in economic goods and services) were quantified in tonnes for food energy and as direct plus indirect energy cost (embodied energy). The fixed solar energy (estimated as primary production) and the direct and indirect auxiliary energy requirements per unit of fish output were expressed in similar units. Similar quantities of living resources in tonnes per unit of salmon biomass output are required whether the salmon are feeding in the sea or are caged farmed. Cage farming is about 10 times more dependent on auxiliary energies than sea ranching. Sea ranching applying delayed release of smolts is 35–45% more efficient in the use of auxiliary energies than conventional sea ranching and cage farming. Restriction of offshore fishing would make sea ranching 3 to 6.5 times more efficient than cage farming. The fixed solar energy input to Atlantic salmon aquaculture is 4 to 63 times larger than the inputs of auxiliary energy. Thus, cage farming and sea ranching are both heavily dependent on the productivity of natural ecosystems. It is concluded that sustainable development of the aquaculture industry must be founded on ecologically integrated technologies which utilize the free production in marine ecosystems without exhausting or damaging the marine environment.  相似文献   
107.
新疆干旱区的水环境问题分析及对策   总被引:4,自引:2,他引:4  
陈建江 《干旱环境监测》2002,16(4):223-224,227
在分析新疆特定的自然地理条件及气修水文特征的基础上,讨论了新疆目前面临的水资源短缺、干旱化、沙漠化加剧;水土流失、土壤盐渍化严重;水污染日益严重、水质恶化等主要的水环境问题,对新疆水资源环境的改善提出了相应的对策。  相似文献   
108.
我国城市污水回用现状及前景   总被引:8,自引:0,他引:8  
通过对我国水资源状况和不处理状况的论述,说明了我国城市污水回用的紧迫性、必要性,分析了我国城市污水利用的现状和回用水利用的模式,提出了下一步应解决的问题的思路,展望了我国城市污水回用的前景,以实现水资源开发利用的可持续性发展。  相似文献   
109.
试论我国环境税制的完善   总被引:1,自引:0,他引:1  
在商品经济高度发达的今天,环保事业也逐步走向市场。越来越多的国家开始重视运用经济手段来解决环境危机问题,环境税就是其中倍受青睐的一种手段。我国目前虽已意识到环境税的重要性,但环境税仍是极其薄弱的环节。本文试从分析我国环境税的现状着手,参考国外的先进经验,对完善我国环境税制提出几点建议。  相似文献   
110.
Models that predict distribution are now widely used to understand the patterns and processes of plant and animal occurrence as well as to guide conservation and management of rare or threatened species. Application of these methods has led to corresponding studies evaluating the sensitivity of model performance to requisite data and other factors that may lead to imprecise or false inferences. We expand upon these works by providing a relative measure of the sensitivity of model parameters and prediction to common sources of error, bias, and variability. We used a one-at-a-time sample design and GPS location data for woodland caribou (Rangifer tarandus caribou) to assess one common species-distribution model: a resource selection function. Our measures of sensitivity included change in coefficient values, prediction success, and the area of mapped habitats following the systematic introduction of geographic error and bias in occurrence data, thematic misclassification of resource maps, and variation in model design. Results suggested that error, bias and model variation have a large impact on the direct interpretation of coefficients. Prediction success and definition of important habitats were less responsive to the perturbations we introduced to the baseline model. Model coefficients, prediction success, and area of ranked habitats were most sensitive to positional error in species locations followed by sampling bias, misclassification of resources, and variation in model design. We recommend that researchers report, and practitioners consider, levels of error and bias introduced to predictive species-distribution models. Formal sensitivity and uncertainty analyses are the most effective means for evaluating and focusing improvements on input data and considering the range of values possible from imperfect models.  相似文献   
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