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91.
Regulators across many different jurisdictions and industries have recently adopted the practice of setting access prices based on the current costs of providing the relevant facilities. Though widely regarded as being efficient, the efficiency implications of using current costs instead of historical costs have not been formally analyzed. Our analysis shows that given stochastic costs, forward-looking access prices retard investment and are generally dominated by access prices determined by historical cost whenever investment is desired.  相似文献   
92.
OPTION VALUE     
The option value of a good is the amount which potential consumers of the good are prepared to pay now, to ensure that the good remains available for future purchase. Option values should be considered when making resource allocation decisions, so that efficient decisions are made. The theoretical basis of option value is described and the problems involved in the recognition, use and measurement of option value are discussed.  相似文献   
93.
94.
The phenomenon of the clearance of deep-rooting vegetation leading to dryland salinity exhibits a number of characteristics which indicate the presence of market failure. These are discussed in the context of identifying an optimal level of clearance in a particular catchment. Various policies could be applied in order to correct for these problems. The potential for the use of taxes and regulations is examined and their limitations are identified. A scheme involving the use of transferable rights to cleared land is described and evaluated by means of a hypothetical example. Controls over land clearance will be more easily achieved when they are introduced at an early stage in the land development process.  相似文献   
95.
Applying a difference‐in‐difference approach with propensity score matching, we examine the impact of participation in the Entry Level Stewardship (ELS) scheme on cereal farm incomes in eastern England. We assess the extent to which impacts are related to a) the source of income affected – whether only from agricultural or total business income; b) the channel of the impact – through land use and/or labour input; and c) the level of impacts through time. In addition, we assess the appropriateness of the level of the ELS payment. We find that: a) entering the ELS scheme could negatively affect cereal farm incomes – in particular, the total business income; b) that negative impacts arise primarily in relation to the use of land resources; c) that impacts may diminish over a relatively short period of time; and d) that the ELS payment broadly compensates for losses without providing over compensation. Given the diminishing negative impact over time, the level of ELS payment might need to be reviewed in the longer term, although policy evaluation should consider the wider implications for efficiency of alternative payment levels. We also discuss some limitations of the approach and potential extensions.  相似文献   
96.
Nutrient emissions from pastoral agriculture are a global cause of declining water quality. Their management is complicated through variability arising from climate and soil influences. This paper compares the implications of input‐based policies and direct restrictions on leaching to achieve 10 and 20 per cent reductions in nitrogen (N) load, in the context of pasture‐based New Zealand dairy farms. The most important mitigation practices on these farms are de‐intensification (involving reductions in N fertiliser application and stocking rate) and the application of nitrification inhibitors. A stylised conceptual model, incorporating both sources of variability, is used to identify the implications of alternative policies. Direct restriction of estimated N leaching is the most cost‐effective policy to reduce N leaching by 10 and 20 per cent. These results indicate the general insufficiency of input‐based mechanisms for water quality improvement, given the low correlation between input use and leaching, possible substitution with unrestricted inputs and their failure to motivate the use of mitigation strategies. Additionally, model output indicates that inherent variability in water quality, mainly due to climate influences, can dominate the benefits of regulatory action in any given year.  相似文献   
97.
The Governance of Rural Land in a Liberalised World   总被引:1,自引:0,他引:1  
Liberalisation of agricultural policies reduces the influence of policy on land‐use decisions, but environmental policy objectives remain. Governance provides an approach that recognises the role of institutions and collective action. The formulation of environmental policy objectives in terms of the provision of public goods raises questions as to the role of economic valuation and as to whether the definition of ‘goods’ may misdirect policy attention. An alternative approach relates to ecosystem services and sees management issues in terms of ecosystem resilience and the adaptive governance of socio‐ecological systems. Governance involves a mix of regulation, markets, government incentives and collective action. Regulation sets the domain within which markets operate and social judgements as to property rights are required as a basis for exchanges. Depending on commodity prices, agri‐environment schemes may be required either to reduce agricultural production intensity or to keep land under production. The diffuse nature of the environmental benefits and costs of land uses, the complexity of ecosystems and the need to co‐ordinate land management decisions indicate a role for local adaptive co‐management of land resources. Governments play a major role in supporting the institutional framework within which this can take place.  相似文献   
98.
European agri-environmental policy for the 21st century   总被引:1,自引:0,他引:1  
The present paper reviews the development of agri-environmental policy in Europe and assesses its prospects. While it does so from a predominantly UK perspective, there are many common features of the experience and policy choices across the majority of Member States. The first generation of agri-environmental measures applied command-and-control regulation for the prevention of pollution. Second-generation measures pay farmers for providing environmental public goods. The emphasis on 'amenity' derived from the maintenance of agricultural production systems contrasts with policy approaches in Australia and the USA. Well-designed incentive schemes constitute 'quasi-markets' for public goods, correcting for a pre-existing market failure. Problems in the delivery of policy include poor spatial targeting and a lack of clarity between environmental and income support objectives. Various changes will be required in order to increase the environmental effectiveness and efficiency of agri-environmental mechanisms.  相似文献   
99.
Strategies to reduce phosphorus and sediment yields are identified for two Australian catchments using a nonlinear optimisation model. This provides novel insight into the cost‐effective management of dual pollutants of water courses in Australia. A strong degree of complementarity between the two pollutants is highlighted, given the adsorption of phosphorus to sediment that augments the value of gully and streambank management for mitigation. However, the relationship between the two pollutants is asymmetric. A 30 per cent reduction in phosphorus yield achieves a 75 per cent reduction in sediment yield in one catchment, while a 30 per cent reduction in sediment yield achieves only a 12 per cent reduction in phosphorus yield. Sediment abatement costs are low given the efficiency of gully and streambank management. A 30 per cent phosphorus reduction lowers profit by 3–7 per cent, while a 30 per cent sediment reduction lowers profit by around 1 per cent. Land‐use optimisation requires spatial heterogeneity in land‐use and gully/streambank management responses. Overall, this research demonstrates the need to determine whether one pollutant is more important than another, while recognising the potential that mitigation practices possess for the reduction of multiple emissions during their evaluation.  相似文献   
100.
Legislation emanating from the European Community is establishing pressures to take action to reduce the level of nitrates in water, and the principles established towards environmental management indicate an emphasis on prevention rather than treatment. This paper analyses three possible approaches by means of controls on fertilisers, on nitrate leaching and on land use. These are incorporated into a linear programming model of a catchment in Cambridgeshire. The results indicate the superior cost-effectiveness of controls over leaching and the severe impact which taxes would have on farm incomes. A system of permits on land use is found to be relatively cost-effective and to offer an administratively feasible alternative.  相似文献   
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