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1.
Bushmeat hunting, a key source of dietary protein, has been implicated as a major extinction threat to tropical vertebrate species in West Africa. Ideally, any such hunting of wild species should be done sustainably, with off-take levels low enough to ensure viability of harvested species. Recent work purports to show that a mature bushmeat market in a major city in Ghana operates sustainably after depletion of vulnerable, slow-reproducing species (Cowlishaw and others 2005). I revisit two aspects of this work. First, I retest the prediction that larger species are transported to the market from greater distances, as expected if overexploitation depletes large species close to the city. Cowlishaw and others failed to find a significantly positive relationship between species-specific body mass and distance between capture site and the market. However, my reanalysis provides evidence for a positive relationship after all, consistent with unsustainable harvesting. In particular, ungulate species were harvested significantly farther from the market than smaller-bodied rodent species. Second, I caution that just because species “persist” in the marketplace in no way implies that they can withstand hunting pressure elsewhere and so should be of little concern to conservationists. I reveal that such species, despite their high intrinsic rates of population growth, are not robust elsewhere. Several of them have disappeared from a network of protected areas in Ghana (Brashares and others 2001). I show that faster-reproducing species are not necessarily more likely to persist in protected areas. The mere presence of fast-reproducing species in a mature bushmeat market should not be construed as generalizable robustness; criteria for ecological sustainability should ensure viability; and harvested species should be robust, not highly prone to extinction, in protected areas.  相似文献   

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Though characterized by a scarcity of water, West Asia and North Africa region has a large number of wetlands of various types supporting a rich biodiversity. However, the government efforts to reverse the trend of wetlands degradation fall short of the policy goals due to various reasons. The paper outlines the priorities for wetlands conservation in the region.  相似文献   

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In Liberia, as in many developing countries, electrification of towns and cities throughout the country has long been a major development goal. However, fuel expenditures by the Liberian Electricity Corporation (LEC) for its rural public stations represent a major and growing burden on the financially hard-pressed utility. In this paper we evaluate the economics of supplying wood to rural electric power plants utilizing different sources of feedstock. We also evaluate the cost implications of differences in wood supply requirements based on the use of steam or gasifier technology, and from variation in plant utilization level.
The wood supply we consider as sources are: (1) retired rubber trees; (2) the harvesting of secondary-growth forest just before the land is returned to temporary cultivation; (3) the establishment of commercial short-rotation wood energy plantations; and (4) adding to the system of shifting agriculture the planting of fast-growing wood species. The results indicate that wood can probably be supplied under a wide range of supply and demand conditions for US$1.00–1.70 per GJ. We estimate that wood steam plants can generate power for about $0.09-0.14 per kWh and gasifier plants for $0.10-0.18 per kWh. These costs are well below the present cost of oil-based rural electric power generation in Liberia (about $0.20–0.27 per kWh).  相似文献   

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Indigenous people and mineral taxation regimes   总被引:1,自引:0,他引:1  
Indigenous people in a number of major mineral-producing countries have established a substantial and growing capacity to tax mineral resources extracted from their traditional lands. However, almost no analysis has been conducted regarding the conceptual and practical issues involved in designing mineral taxation regimes for use by indigenous people. The general literature on mineral taxation is of limited relevance because basic assumptions it makes regarding the nature of the taxing authority (national or state governments) do not apply to indigenous peoples. This article discusses some key characteristics of indigenous communities as they relate to taxation of mineral resources. Against this background, it identifies a number of approaches to mineral taxation which might be utilized by indigenous groups and which acknowledge the specific constraints and circumstances they face while at the same time recognizing their need to attract and maintain investment on their traditional lands. It also reviews the inter-relationship between indigenous and state or governmental tax regimes.  相似文献   

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This paper presents the quantitative results of recent research on Canada's minerals and metals industry, and its international competitiveness for mineral investment. The information and analysis presented are derived from the work of a Canadian government-industry task force that was created in 1991, under the auspices of the Intergovernmental Working Group on the Mineral Industry (IGWG). Much of this work deals with mining taxation in several Canadian provinces. More importantly, an attempt is made to evaluate the total tax burden that the mining industry must bear, on a project basis, at all levels from exploration through refining operations in many important competitor countries. While the focus of the paper is on an international comparison of mining taxation, some non-tax issues relating to Canada's competitiveness for mineral investment are addressed .  相似文献   

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The decline of a regional fishing nation: The case of Ghana and West Africa   总被引:1,自引:0,他引:1  
Inadequate trade policies, globalization of the fishing industry, dominance of Europe's distant water fleets, declarations of exclusive economic zones (EEZs) by neighbouring West African nations, overfishing and a lack of good governance contributed to the decline of Ghana as a regional fishing nation, a position it had held since the 18th century. The prohibitive cost of access arrangements limited Ghana's access to distant waters. The country's marine environments have been impacted by overexploitation of stocks and the use of destructive methods. Subsistence fishing has become the sole means of survival for many fishers. The decline of the fishing sector has limited the country's ability to meet domestic demand and threatened the economic and food security of many Ghanaians. The article traces the early history of Ghana's fisheries, their gradual decline during the last four decades, and outlines recommendations for policy changes to address the situation and steer the nation on a course towards sustainable fisheries.  相似文献   

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During the 1970s and 1980s the main concern of mining policies was to attract investment whilst at the same time balancing the interests of governments and companies. By the turn of the century a new spectrum of challenges faces governments and companies in the mining sector. The need for fiscal regimes to adapt to price cyclicity is to some extent superseded by the requirement that they adapt to a long-term decline of metal prices. The growing importance of environmental and community affairs in the mining sector will force governments to design coherent and comprehensive tax regulations to complement the wide range of initiatives being taken in these fields. Finally, the age-old problem of tax collection continues to raise its head in transition and developing economies.  相似文献   

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Mining generates risk of environmental and social harm for Indigenous peoples but can also generate substantial revenues for them, creating opportunities for community development in a context where economic and social disadvantage is the norm. Especially as mining revenues should, in part, compensate for mining’s negative social and environmental impacts, it is vital that mineral taxation on Indigenous lands reflect a careful assessment of appropriate tax mechanisms and a matching of these with community priorities. Yet little has been written that could serve as a guide for Indigenous decision makers. This article contributes to an understanding of the issues and choices facing Indigenous communities in designing mineral taxation regimes, by focusing on the question of economic risk. Risk arises as a key variable in choosing or designing a mineral taxation regime in three ways. Different approaches to mineral taxation are inherently more or less risky, in the sense that they are more or less certain to generate tax revenues. A second aspect of risk involves the degree of economic certainty or predictability associated with different types of commodities and projects. Third, the risk tolerance of Indigenous peoples and communities can vary significantly. We show how Indigenous groups can integrate and address these different dimensions of risk, by recognising the ‘risk consequences’ associated with different approaches to mineral taxation and choosing an approach that reflects, as fully as possible, the group’s risk tolerance.  相似文献   

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The objective of this review paper is to analyze the efficiency of environmentally motivated taxes on virgin raw materials. We analyze both the economic-theoretical foundations of virgin natural resource taxation, and the empirical experiences of aggregates taxes i.e., taxes on, for instance, gravel, rock, stone, etc. in three European countries. These include Sweden, Denmark and the United Kingdom. The theoretical analysis indicates that taxing natural resource output or use typically represents a ‘second-best’ policy alternative, which can be used when, for instance, the monitoring of non-point source emissions is difficult or efficient property rights regimes cannot be established. The empirical analysis shows that the European aggregate taxes have assisted in reducing virgin resource use in spite of the relatively low own-price responses. However, generators of recycled materials typically have few incentives to enhance their waste sorting activities in the presence of a tax on virgin materials. Unless additional policies to increase the supply of recycled materials are implemented, supply will not increase much even in the presence of high demand. Finally, although second-best taxes are sometimes motivated by the desire to keep administration costs low, they could come at the cost of improper incentives and of limited policy legitimacy.  相似文献   

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There is a need for positive interplay among the various actors in exploration. The licensees have an important role, but the host country's role in managing the assessment of the resources is equally important in promoting effective exploration. Selection of an appropriate concession policy is the main tool for the development of the host country's enterprising capacity both within and outside the petroleum sector. Some of the most important aspects of concession policy are reviewed, with reference to the Norwegian experience as an illustration. The development of infrastructure and institutional development in the country are major elements in resource management in as far as promoting a positive development in the country's enterprising capacity. It is therefore important that licensing as the cardinal element in exploration is implemented within a total resource management strategy.  相似文献   

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石油作为"工业的血液"在社会生产生活的各个环节都起着不可或缺的作用,石油工业的可持续发展无疑是实现可持续发展战略的关键,但目前我国石油工业的可持续发展法律制度还不足以实现石油工业的可持续发展.为此,应建立以可持续发展为基本原则的法律制度体系,围绕环境、经济和社会的可持续发展,完善环境影响评价制度,建立资源区生态补偿制度,落实企业可持续发展报告制度,制定石油行业的HSE法律法规.  相似文献   

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This paper provides a conceptual overview of economists′ attempts to learn about the effects of taxes on extractive resources. The emphasis is on research methods and techniques, with no attempt to provide a comprehensive tabulation of previous empirical results or policy conclusions regarding preferred tax instruments or systems. We argue, in fact, that the nature of such conclusions largely depends on, and is limited by, the researcher′s choice of modeling framework. Many alternative frameworks and approaches have been developed in the literature. Our goal is to describe the differences among them and to note their strengths and limitations.  相似文献   

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Since 1985, there has been rapid growth in the presence of Australian exploration and mining companies in Africa. This paper sets out the reasons for the interest of those companies, now 20 in number, in various African mineral opportunities. Australian companies spent about US$16 million in 1992 on African exploration and evaluation, with over US$130 million spent on new mine development or expansion. The 20 Australian companies operate in 16 African countries, with two areas of focus, West Africa and Southern Africa. Using the responses to a survey sent to Australian companies operating in Africa in 1991, and to companies known to be interested in prospects there, the paper identifies and categorizes the policy and regulatory requirements needed by investors. Although a gloomy picture has often been painted of investment in Africa, Australian companies recognize that their risk taking, in the light of a declining investment climate in other mining areas, could promote a renaissance of world-scale mining in Africa.  相似文献   

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