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151.
Planning for hazard mitigation is frequently detached from other planning activities that influence development patterns in hazardous areas. Consistent integration of mitigation reduces hazard vulnerability for people and the built environment. We apply a plan integration for resilience scorecard in six US coastal cities to evaluate the integration of local networks of plans and the degree to which they target areas most vulnerable to flooding hazards. We find that plan integration scores vary widely across the six cities, and that some plans actually increase vulnerability in hazard zones. Policies also frequently support mitigation in areas with low vulnerability, rather than in areas with high vulnerability. The plan integration for resilience scorecard can generate information to improve hazard planning by allowing planners to identify conflicts between plans, assess whether plans target areas that are most vulnerable, and better inform decision makers about opportunities to mainstream mitigation into multiple sectors of planning.  相似文献   
152.
In order to achieve efficient phytoextraction of heavy metals using trees, the metal allocation to aboveground tissues needs to be characterised. In his study, the distribution of heavy metals, macro- and micronutrients and the metal micro-localisation as a function of the leaf position and heavy metal treatment were analysed in poplars grown on soil with mixed metal contamination. Zinc was the most abundant contaminant in both soil and foliage and, together with cadmium, was preferentially accumulated in older foliage whereas excess copper and lead were not translocated. Changes in other element concentrations indicated an acceleration in aging as a consequence of the metal treatment. Excess zinc was irregularly accumulated inside leaf tissues, tended to saturate the veins and was more frequently stored in cell symplast than apoplast. Storage compartments including metabolically safe and sensitive subcellular sites resulted in sizable metal accumulation as well as stress reactions.  相似文献   
153.
Herbicide resistance in annual ryegrass (ARG, Lolium rigidum) threatens the quality and yield of winter wheat crops in Australia, prompting research to discover novel natural plant compounds with herbicidal properties. Due to its novel nature and potentially interesting chemistry, the Australian native, Wollemi pine (Wollemia nobilis), was tested for its ability to suppress ARG growth and its feasibility for use in weed control strategies. The leaf extract of Wollemi pine significantly inhibited the growth of ARG and wild radish (Raphanus raphanistrum) in laboratory bioassays at concentrations above 1% extract. In soil trials, the 100% extract (100 g dried plant material/L) inhibited the dry weight of ARG by 25%. The addition of a wetting agent to the extract increased the suppression of ARG to 80% which was as phytotoxic as a 4-fold increase in the extract concentration (“400%” extract). Using bioassay-guided fractionation, the most phytotoxic fraction was identified and further analysed via GC/MS. Several compounds not previously identified in Wollemi pine leaf extracts have been identified, namely, 2-propylphenol, 3,4-dimethoxyphenol, 2-methoxybenzoic acid, vanillyl alcohol and isovanillic acid. These results suggest that Wollemi pine is an important potential source of compounds for the control of ARG and wild radish in winter crops.  相似文献   
154.
An overview is provided of the production processes, waste generation, and waste management of the electronics products industries. Chosen product areas include electron tubes, semiconductors, capacitors/resistors, and printed circuit/wiring boards. Examples are given of specific processes and associated waste streams. Waste minimization activities are identified, and specific examples of successful applications provided. While faced with a wide variety of waste streams, many opportunities for waste minimization exist and await only application.  相似文献   
155.
While much work has been invested in addressing the economic and technical basis of disaster preparedness, less effort has been directed towards understanding the cultural and social obstacles to and opportunities for disaster risk reduction. This paper presents local insights from five different national settings into the cultural and social contexts of disaster preparedness. In most cases, an early warning system was in place, but it failed to alert people to diverse environmental shocks. The research findings show that despite geographical and typological differences in these locations, the limitations of the systems were fairly similar. In Kenya, people received warnings, but from contradictory systems, whereas in the Philippines and on the island of Saipan, people did not understand the messages or take them seriously. In Bangladesh and Nepal, however, a deeper cultural and religious reasoning serves to explain disasters, and how to prevent them or find safety when they strike.  相似文献   
156.
Employees' beliefs about how promotions are awarded within their organizations can have important consequences. We conducted two studies that focus on perceptions of the criteria used to make promotion decisions. In Study 1, we identified two types of perceived promotion criteria, performance‐based and nonperformance‐based. Then we use justice and social exchange theories to develop a model linking employee perceptions of promotion criteria to performance via their relationships with promotional justice and organizational commitment. In a sample of 305 employee–supervisor pairs, we found that both promotional justice and organizational commitment mediated between perceptions of promotion criteria and supervisor rated in‐role and extra‐role performance, and that having received a promotion in the past predicted attributions that promotions were based relatively more on performance or nonperformance criteria. Study 2 further examined the role of promotions themselves in the formation of perceptions of promotion criteria. Drawing from image and attribution theories, we hypothesized that the relationship between having received a promotion or not and perceptions of promotion criteria depends on ego defensiveness. In a sample of 145 employees, we found that those who scored high on ego defensiveness and who had not been promoted were especially likely to attribute promotion decisions to nonperformance criteria. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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159.
Unprecedented global changes caused by human actions challenge society's ability to sustain the desirable features of our planet. This requires proactive management of change to foster both resilience (sustaining those attributes that are important to society in the face of change) and adaptation (developing new socioecological configurations that function effectively under new conditions). The Arctic may be one of the last remaining opportunities to plan for change in a spatially extensive region where many of the ancestral ecological and social processes and feedbacks are still intact. If the feasibility of this strategy can be demonstrated in the Arctic, our improved understanding of the dynamics of change can be applied to regions with greater human modification. Conditions may now be ideal to implement policies to manage Arctic change because recent studies provide the essential scientific understanding, appropriate international institutions are in place, and Arctic nations have the wealth to institute necessary changes, if they choose to do so.  相似文献   
160.
Climate change effects on hydroecology of arctic freshwater ecosystems   总被引:2,自引:0,他引:2  
In general, the arctic freshwater-terrestrial system will warm more rapidly than the global average, particularly during the autumn and winter season. The decline or loss of many cryospheric components and a shift from a nival to an increasingly pluvial system will produce numerous physical effects on freshwater ecosystems. Of particular note will be reductions in the dominance of the spring freshet and changes in the intensity of river-ice breakup. Increased evaporation/evapotranspiration due to longer ice-free seasons, higher air/water temperatures and greater transpiring vegetation along with increase infiltration because of permafrost thaw will decrease surface water levels and coverage. Loss of ice and permafrost, increased water temperatures and vegetation shifts will alter water chemistry, the general result being an increase in lotic and lentic productivity. Changes in ice and water flow/levels will lead to regime-specific increases and decreases in habitat availability/quality across the circumpolar Arctic.  相似文献   
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