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91.
Hydrologic analysis for coastal wetland restoration   总被引:1,自引:0,他引:1  
Increasing recognition of the value of tidal wetlands has led to interest in how to restore and enhance areas that have been modified by human activity. The policy of recognizing restoration or enhancement as mitigation for destruction of other wetlands is controversial. Once policy questions are separated from technical questions, the steps in a successful project are straightforward A key element in the design of a successful project is quantitative hydraulic and hydrologic analysis of alternatives. Restoration projects at two sites in California used a combination of empirical geomorphic relationships, numerical modeling, and verification with field observations. Experience with these and other wetland restoration projects indicates the importance of longterm postproject monitoring, inspection, and maintenance  相似文献   
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Activities in Brazil's forest sector have substantial potential for mitigating global warming as well as additional environmental and other benefits. Silvicultural plantations of different types, reduced impact logging, and deforestation avoidance all have potential mitigation roles. The magnitude of the annual emission from recent rates of deforestation in Amazonia presents an opportunity for carbon (C) benefits through reducing current rates of deforestation. Measures related to Amazonian deforestation have greater potential carbon benefits than do options such as plantation silviculture, but much depends on how benefits are calculated. Procedures are needed for assessing the environmental and social impacts of Clean DevelopmentMechanism (CDM) projects.  相似文献   
94.
This paper presents a case study of negotiations over the combination of a small manufacturing firm into a multi-billion dollar conglomerate following its 'white knight' acquisition. It focuses on the strategic and tactical conflicts between the two firms and traces these to the party's emotional reactions to the combination. Feeling of loss versus gain in the two firms, each party's sense of uncertainty and threat, and their moves toward proactive versus reactive control in the combination are analysed to identify the roots of strategic conflict. These feelings, plus incompatibilities in the two company's managements, business systems, corporate cultures, and goals for combination ramify in conflict in the negotiations themselves. The paper concludes with a more generic model illustrating contextual features of combinations that shape human reactions and conflicts in negotiations after the sale.  相似文献   
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In this article, Rohm & Haas' Responsible Care® implementation strategy and management system verification (MSV) experiences are detailed. Recommendations on how to strengthen the verification process are provided.  相似文献   
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Brazil’s BR-319 Highway linked Manaus, in the state of Amazonas, to Porto Velho, Rondônia, until it became impassable in 1988. Now it is proposed for reconstruction and paving, which would facilitate migration from the “Arc of Deforestation” in the southern part of the Amazon region to new frontiers farther north. The purpose of the highway, which is to facilitate transport to São Paulo of products from factories in the Manaus Free Trade Zone, would be better served by sending the containers by ship to the port of Santos. The lack of a land connection to Manaus currently represents a significant barrier to migration to central and northern Amazonia. Discourse regarding the highway systematically overestimates the highway’s benefits and underestimates its impacts. A variety of changes would be needed prior to paving the highway if these potential impacts are to be attenuated. These include zoning, reserve creation, and increased governance in various forms, including deforestation licensing and control programs. More fundamental changes are also needed, especially the abandonment of the long-standing tradition in Brazil of granting squatters’ rights to those who invade public land. Organizing Amazonian occupation in such a way that road construction and improvement cease to lead to explosive and uncontrolled deforestation should be a prerequisite for approval of the BR-319 and other road projects for which major impacts are expected. These projects could provide the impetus that is needed to achieve the transition away from appropriation of public land by both small squatters and by grileiros (large-scale illegal claimants). A delay in reconstructing the highway is advisable until appropriate changes can be effected.  相似文献   
99.
For some time now, ecological economists have been putting forward a ‘threshold hypothesis’ – the notion that when macroeconomic systems expand beyond a certain size, the additional cost of growth exceeds the flow of additional benefits. In order to support their belief, ecological economists have developed a number of similar indexes to measure and compare the benefits and costs of growth (e.g., the Index of Sustainable Economic Welfare and the Genuine Progress Indicator). In virtually every instance where an index of this type has been calculated for a particular country, the movement of the index appears to reinforce the existence of the threshold hypothesis. Of late, a number of observers have expressed concerns about whether these alternative indexes reflect concrete reality or the prejudices of ecological economists. In view of these concerns, this paper closely examines the valuation methods used in the calculation the Index of Sustainable Economic Welfare, the Genuine Progress Indicator, and the Sustainable Net Benefit Index. It is argued that a consistent and more robust set of valuation techniques is required in order for these alternative indexes to gain broad acceptability.*Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
100.
Radon concentrations were measured in several locations in each of approximately 100 dwellings in central Maine and in Houston, TX. Integrated samples were taken during the heating (or cooling) seasons with commercially available passive alpha track devices, while grab samples were taken at the time of integrated sampler deployment. It was found that both indoor and outdoor measurements in both areas were distributed log normally, and that the geometric mean of indoor measurements in Maine was three times higher than that of corresponding measurements in the Houston area. It was also noted that the mean of the indoor grab sample measurements was not significantly different from the mean of the indoor integrated measurements, and that the degree of correlation between the grab samples and a given indoor integrated sample was nearly as good as between integrated samples taken at different living area locations.  相似文献   
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