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251.
This article exemplifies an approach to analyzing political arguments and press deliberation on the issue of climate change and oil policy. I apply political discourse analysis to examine an oil minister's press conference presentation of the key official document on Norway's future oil policy, and evaluate how he attempted to reconcile the country's expansive petroleum policy with its self-proclaimed ambition of being world leading in responsible climate policy. The analysis displays how the minister's argumentation served to legitimate an expansive oil policy by projecting an altruistic motivation and invoking the authority of the tradition of the industry. This is supplemented by an analysis of newspaper editorials and commentaries on the speech, identifying a major split in viewpoints between local and national newspapers. The analyses evaluate arguments in an explicit manner, for example by critically questioning their value premises, thus suggesting an approach that could benefit critical research on environmental communication.  相似文献   
252.
Nowadays forestry faces a complex management situation; the understanding of sustainable forest management (SFM) has gone far beyond the original meaning of sustainable yield of timber. SFM strategies should fulfil ecological, economic and social functions without causing damage to other ecosystems. In this understanding, forest management actions cannot be seen as isolated or mono-causal. In this case study, indicators for SFM are arranged in a Pressure-State-Response (PSR) framework at forest management unit level. This framework links pressures on the environment caused by human activities with changes of environmental state (condition) parameters. Forest management also responds to these changes by instituting environmental and economic measures to reduce pressures and restore natural resources. The Analytic Network Process (ANP) is utilized to evaluate the performance of four management strategies with regard to the PSR framework on SFM. Priorities of indicators and alternatives are modelled with the ANP resulting from the interconnections to other indicators and their respective cumulative importance. The approach allows for more detailed information on the network of human influences and their impacts on forest ecosystems and goes beyond the limitations of flat-dimensioned indicator sets.  相似文献   
253.
Analytical solutions for flow fields near continuous wall reactive barriers   总被引:1,自引:0,他引:1  
Permeable reactive barriers (PRBs) are widely applied for in-situ remediation of contaminant plumes transported by groundwater. Besides the goal of a sufficient contaminant remediation inside the reactive cell (residence time) the width of plume intercepted by a PRB is of critical concern. A 2-dimensional analytical approach is applied to determine the flow fields towards rectangular PRBs of the continuous wall (CW) configuration with and without impermeable side walls (but yet no funnel). The approach is based on the conformal mapping technique and assumes a homogeneous aquifer with a uniform ambient flow field. The hydraulic conductivity of the reactive material is furthermore assumed to exceed the conductivity of the aquifer by at least one order of magnitude as to neglect the hydraulic gradient across the reactor. The flow fields are analyzed regarding the widths and shapes of the respective capture zones as functions of the dimensions (aspect ratio) of the reactive cell and the ambient groundwater flow direction. Presented are an improved characterization of the advantages of impermeable side walls, a convenient approach to improved hydraulic design (including basic cost-optimization) and new concepts for monitoring CW PRBs. Water level data from a CW PRB at the Seneca Army Depot site, NY, are used for field demonstration.  相似文献   
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