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91.
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   
92.
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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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   
97.
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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Bottleneck(s) or Metapopulation in Cheetahs   总被引:2,自引:0,他引:2  
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100.
Ellis AM  Lounibos LP  Holyoak M 《Ecology》2006,87(10):2582-2590
Four different conceptual models of metacommunities have been proposed, termed "patch dynamics," "species sorting", "mass effect", and "neutral". These models simplify thinking about metacommunities and improve our understanding of the role of spatial dynamics both in structuring communities and in determining local and regional diversity. We tested whether mosquito communities inhabiting water-filled tree holes in southeastern Florida, U.S.A., displayed any of the characteristics and dynamics predicted by the four models. The densities of the five most common species in 3-8 tree holes were monitored every two weeks during 1978-2003. We tested relationships between habitat variables and species densities, spatial synchrony, the presence of life history trade-offs, and species turnover. Dynamics showed strong elements of species sorting, but with considerable turnover, as predicted by the patch dynamics model. Consistent with patch dynamics, there was substantial asynchrony in dynamics for different tree holes, substantial species turnover in space and time, and an occupancy/colonization trade-off. Substantial correlations of density and occupancy with tree hole volume were consistent with the species-sorting model, but unlike this model, species did not have permanent refuges. No evidence of mass effects was found, and correlations between habitat variables and dynamics were inconsistent with neutral models. Our results did not match a single model and therefore caution against overly simplifying metacommunity dynamics by using one dynamical characteristic to select a particular metacommunity perspective.  相似文献   
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