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31.
As local governments have moved toward adopting sustainability policies, there have been some cases where local Tea Parties have emerged as aggressive and strident opponents of such changes. Looking broadly at the Tea Party movement across the United States and systematically measuring its influence in urban America, we assess each Tea Party chapter’s capacity – its ability to convert resources into meaningful political advocacy. Data is derived from surveys of political elites in 50 cities as well as from determining the level of sustainability programming in each of these same cities. Evidence demonstrates that the Tea Party has not had a significant impact on city policymaking in the area of sustainability. Rather, the typical Tea Party chapter appears to be at best a modest presence in local politics. 相似文献
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The machair sand dune systems of the Outer Hebrides of Scotland are a unique habitat, which is rare within both a global and
European context. Unusually, the machair habitat also represents an agricultural resource that is very important to the Hebridean
people, having been subject to both grazing and cultivation throughout the historical period. Following designation as an
Environmentally Sensitive Area (ESA) in 1988, the machairs of South Uist have been studied with the aim of understanding the
links between agricultural practice and their plant community and ecosystem dynamics. This research focused primarily on the
effects of cultivation practices and their role in maintaining plant species richness and community and ecosystem stability.
Within two carefully selected areas, the successional plant communities of machair at different stages of recovery following
ploughing and cultivation of cereals and potato patches or ‘lazy beds’ were identified at both a macro- and micro-level. Investigations
of the vegetation recovery processes on turves taken from newly ploughed land indicated that the initial stages of recolonization
are characterized primarily by rapid vegetative reproduction and growth, although re-vegetation by seeds is also an important
factor. The implications of these findings for the long-term management of machair plant communities are discussed and in
particular the need to maintain old cultivation practices such as shallow ploughing. The need for more detailed research into
both seed banks and seed rain and into processes of vegetative reproduction is stressed.
Nomenclature: Clapham et al. (1981) and Stace (1991, 1997) for vascular plants; Hubbard (1984) for grasses; Pankhurst & Mullin (1991) for
the regional flora; Dobson (1992) for lichens; Watson (1981) for mosses and liverworts. 相似文献
34.
The UK is reportedly an international leader in the application of environmental policy appraisal (EPA). From the late 1980s until 2004, UK central government sought to produce ex ante assessments of the potential environmental impacts of different policy options. Critics maintain that EPA had a very limited impact on policy-making activities in Whitehall departments. However, the empirical basis for these claims is surprisingly thin. This paper seeks to better understand what facilitated or retarded EPA by looking at its use in Whitehall, with the aim being to draw lessons for the UK's new and more integrated appraisal regime, as well as similar systems in the European Union. The paper finds that the implementation of EPA was both weak and highly sectorised, and that there is an underlying resistance to policy appraisal per se in Whitehall. These weaknesses urgently need to be addressed otherwise new systems of integrated appraisal will not deliver what is expected of them. 相似文献
35.
Kondolf GM Angermeier PL Cummins K Dunne T Healey M Kimmerer W Moyle PB Murphy D Patten D Railsback S Reed DJ Spies R Twiss R 《Environmental management》2008,42(6):933-945
Despite increasingly large investments, the potential ecological effects of river restoration programs are still small compared
to the degree of human alterations to physical and ecological function. Thus, it is rarely possible to “restore” pre-disturbance
conditions; rather restoration programs (even large, well-funded ones) will nearly always involve multiple small projects,
each of which can make some modest change to selected ecosystem processes and habitats. At present, such projects are typically
selected based on their attributes as individual projects (e.g., consistency with programmatic goals of the funders, scientific
soundness, and acceptance by local communities), and ease of implementation. Projects are rarely prioritized (at least explicitly)
based on how they will cumulatively affect ecosystem function over coming decades. Such projections require an understanding
of the form of the restoration response curve, or at least that we assume some plausible relations and estimate cumulative
effects based thereon. Drawing on our experience with the CALFED Bay-Delta Ecosystem Restoration Program in California, we
consider potential cumulative system-wide benefits of a restoration activity extensively implemented in the region: isolating/filling
abandoned floodplain gravel pits captured by rivers to reduce predation of outmigrating juvenile salmon by exotic warmwater
species inhabiting the pits. We present a simple spreadsheet model to show how different assumptions about gravel pit bathymetry
and predator behavior would affect the cumulative benefits of multiple pit-filling and isolation projects, and how these insights
could help managers prioritize which pits to fill. 相似文献
36.
David Poulard Damien Subit Bingbing Nie John-Paul Donlon Richard W. Kent 《Traffic injury prevention》2015,16(7):S87-S95
Objective: The objective of this study was to discuss the influence of the pre-impact posture to the response of a finite element human body model (HBM) in frontal impacts.Methods: This study uses previously published cadaveric tests (PMHS), which measured six realistic pre-impact postures. Seven postured models were created from the THUMS occupant model (v4.0): one matching the standard UMTRI driving posture as it was the target posture in the experiments, and six matching the measured pre-impact postures. The same measurements as those obtained during the cadaveric tests were calculated from the simulations, and biofidelity metrics based on signals correlation (CORA) were established to compare the response of the seven models to the experiments.Results: The HBM responses showed good agreement with the PMHS responses for the reaction forces (CORA = 0.80 ± 0.05) and the kinematics of the lower part of the torso but only fair correlation was found with the head, the upper spine, rib strains (CORA= 0.50 ± 0.05) and chest deflections (CORA = 0.67 ± 0.08). All models sustained rib fractures, sternal fracture and clavicle fracture. The average number of rib fractures for all the models was 5.3 ± 1.0, lower than in the experiments (10.8 ± 9.0).Variation in pre-impact posture greatly altered the time histories of the reaction forces, deflections and the rib strains, mainly in terms of time delay, but no definite improvement in HBM response or injury prediction was observed. By modifying only the posture of the HBM, the variability in the impact response was found to be equivalent to that observed in the experiments. The postured HBM sustained from 4 to 8 rib fractures, confirming that the pre-impact posture influenced the injury outcome predicted by the simulation.Conclusions: This study tries to answer an important question: what is the effect of occupant posture on kinematics and kinetics. Significant differences in kinematics observed between HBM and PMHS suggesting more coupling between the pelvis and the spine for the models which makes the model response very sensitive to any variation in the spine posture. Consequently, the findings observed for the HBM cannot be extended to PMHS. Besides, pre-impact posture should be carefully quantified during experiments and the evaluation of HBM should take into account the variation in the predicted impact response due to the variation in the model posture. 相似文献
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Possibilities for greater variation in landscaping during the reclamation of derelict colliery spoil heaps and the potential of a regional approach to the survey of revegetation problems are introduced. A survey method for assessing plant growth problems is described which incorporates rapid measurement of physical and chemical constraints to plant growth and which uses bioassay trials as an index of plant growth potential. The use of the survey method on 34 closed and disused sites in the Barnsley and South Yorkshire areas of the National Coal Board is outlined and suggestions for the incorporation of such data in recommendations for the reclamation of individual sites are made. 相似文献
40.