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841.
States use a variety of approaches to encourage landowners and loggers to apply ecologically-sustainable timber harvesting practices, the latter generically referred to as timber harvesting guidelines. A survey of 37 state forestry agency administrators in the eastern U.S. (defined as a contiguous region with the northwest and southwest borders being North Dakota and Texas, respectively) was conducted in 2000 to assess the extent and nature of state guideline programs and the various methods by which states encourage their use. The study found states in the eastern U.S. use a variety of policy tools to promote guideline use, with certain policy tools more common for certain target audiences (e.g., loggers) as well as the types of resources (e.g., wildlife habitat) addressed by the guidelines. Eighty-three percent of the programs directed at encouraging forest landowners in the eastern U.S. to use the timber harvesting practices identified in their state guidebooks are technical assistance, educational, or cost-share programs. Technical assistance and education programs are the most common policy tools used to assist loggers in applying sustainable harvesting practices. Technical assistance and cost-share programs consistently rank among the most effective policy tools for encouraging loggers and landowners to apply the guidelines. Comparing the level of program investment to perceived benefits, assistance programs and education programs rank most efficient landowner programs, whereas premium prices for products and preferential access to contracts are the two most efficient programs directed at loggers. The paper concludes with an assessment of emerging trends and additional information needs associated with encouraging the application of sustainable timber harvesting practices. 相似文献
842.
M. L. Livingston D. C. Gory 《Journal of the American Water Resources Association》1998,34(6):1311-1317
ABSTRACT: The contribution of agriculture to nitrate pollution of 8Urface and ground water is a growing concern throughout the world. The objective of this article is to evaluate the current environmental policy governing nitrate contamination of ground water in the South Platte alluvial aquifer. In particular, the “best management practice” approach is assessed in its relationship to optimal policy design. First, the current physical environmental problem and existing institutional arrangements are described. Second, legal and economic criteria are brought to bear on the question of appropriate policy design. Finally, the strengths and weaknesses of the existing policy are evaluated in this context and changes in policy that would increase effectiveness are recommended. Considerable justification is found for state-initiated control because victims of ground water pollution are dispersed and risk assessment is technically demanding. However, ex post elements of existing policy must be improved, perhaps through targeting and some devolution in monitoring and enforcement responsibilities. 相似文献
843.
Nicholas Leader 《Disasters》1998,22(4):288-308
The international humanitarian system is seen by many to be in crisis. The reasons for this are complex but include the perception held by many that there is an increasing ambivalence on the part of powerful states to invest military, political and financial resources in upholding humanitarian principles, and a growing feeling that much humanitarian action both ignores human rights issues and can prolong conflict. As a result, much attention has focused on the notion of 'humanitarian principles' and there has been a proliferation of statements and initiatives on this topic in recent years. 相似文献
844.
Joanna Macrae 《Disasters》1998,22(4):309-317
Over recent years, the humanitarian community has been under increasing scrutiny and attracted harsh criticism. This mounting critique of humanitarianism has shifted from being concerned primarily with the poor functioning of the humanitarian system to one targeted on basic humanitarian values. This paper is concerned to understand the factors driving the attack on humanitarian values. It identifies four apparently disparate groups who are interested in attacking these values: the anti-imperialists, the realpolitikers, the developmentalists and the neo-peaceniks. It concludes that unless humanitarian actors are aware of these diverse threats to their values and operations, they risk being co-opted or marginalised. 相似文献
845.
846.
J.C. Doornkamp 《Journal of environmental management》1998,52(4):327-333
A review of the difficulties associated with the definition of coastal flood frequencies and magnitudes leads to a recognition that there is considerable doubt in many parts of the world as to the precise nature of this particular hazard. Similarly, a review of the sea-level measurements that have been used to indicate a response to global warming shows that there is uncertainty about the amount of other controlling influences. What is clear, however, are that past management decisions about human endeavours in the coastal zone (including flood defences, occupance of flood-prone lands, extraction of ground water and natural gas) have had an impact on relative land and sea levels and have done more to increase the risk of coastal flooding than can be assigned so far to global warming. In addition, these changes induced by human activity may render inappropriate calculations of coastal-flood frequencies based on historical records since the latter relate to a period of time when the controls on flooding may have been very different. 相似文献
847.
对上海当前防灾救灾系统管理中存在的问题进行了分析,并且提出了相应的对策,对上海及其它城市的防灾救灾系统管理体系的改进与完善有一定的借鉴作用。 相似文献
848.
本文在简介莱斯特·布朗关于21世纪中国粮食问题论点的基础上、分析了21世纪解决中国粮食问题的有利因素与发展潜力、不利因素与潜在危机.提出了与此相关的理论导向和政策选择。 相似文献
849.
Deborah H. Lee Thomas E. Croley Frank H. Quinn 《Journal of the American Water Resources Association》1997,33(1):55-69
ABSTRACT: The implications of Lake Ontario regulation under transposed climates with changed means and variability are presented for seasonal and annual time scales. The current regulation plan is evaluated with climates other than the climate for which it was developed and tested. This provides insight into potential conflicts and management issues, development of regulation criteria for extreme conditions, and potential modification of the regulation plan. Transposed climates from the southeastern and south central continental United States are applied to thermodynamic models of the Great Lakes and hydrologic models of their watersheds; these climates provide four alternative scenarios of water supplies to Lake Ontario. The scenarios are analyzed with reference to the present Great Lakes climate. The responses of the Lake Ontario regulation plan to the transposed climate scenarios illustrate several key issues: (1) historical water supplies should no longer be the sole basis for testing and developing lake regulation plans; (2) during extreme supply conditions, none of the regulation criteria can be met simultaneously, priority of interests may change, and new interests may need to be considered, potentially requiring substantial revision to the Boundary Waters Treaty of 1909; (3) revised regulation criteria should be based on ecosystem health and socio-economic benefits for a wider spectrum of interests and not on frequencies and ranges of levels and flows of the historical climate; and (4) operational management of the lake should be improved under the present climate, and under any future climate with more variability, through the use of improved water supply forecasts and monitoring of current hydrologic conditions. 相似文献
850.
Olen Paul Matthews 《Journal of the American Water Resources Association》1994,30(2):189-196
ABSTRACT: The American Society of Civil Engineers (ASCE) Model State Water Code provides suggested statutory language and commentary helpful in guiding western water law reform. Departing from the past preference for stream diversions and consumptive uses, the code is sensitive to the public's interest in maintaining environmental quality. The traditional doctrine protected inefficient uses and in some states hampered transfers. The model code addresses these issues as well as advocating integrated manage. meat and water resource planning. The debate on how to reform water law has already started, and the model code provides material useful in the reform process. Even with the current draft code, a few gaps exist for later resolution. 相似文献