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201.
Regional Environmental Change - Most studies of major disasters focus on the impacts of the event and the short-term responses. Some evaluate the underlying causes of vulnerability, but few...  相似文献   
202.
Environmental Management - Land managers of natural areas are under pressure to balance demands for increased recreation access with protection of the natural resource. Unintended dispersal of...  相似文献   
203.
204.
Deliberation and Scale in Mekong Region Water Governance   总被引:1,自引:0,他引:1  
Understanding the politics of deliberation, scales, and levels is crucial to understanding the social complexity of water-related governance. Deliberative processes might complement and inform more conventional representational and bureaucratic approaches to planning and decision-making. However, they are also subject to scale and level politics, which can confound institutionalized decision-making. Scale and level contests arise in dialogues and related arenas because different actors privilege particular temporal or spatial scales and levels in their analysis, arguments, and responses. Scale contests might include whether to privilege administrative, hydrological, ecosystem, or economic boundaries. Level contests might include whether to privilege the subdistrict or the province, the tributary watershed or the international river basin, a river or a biogeographic region, and the local or the regional economy. In the Mekong Region there is a recurrent demand for water resources development projects and major policies proposed by governments and investors to be scrutinized in public. Deliberative forms of engagement are potentially very helpful because they encourage supporters and critics to articulate assumptions and reasoning about the different opportunities and risks associated with alternative options, and in doing so, they often traverse and enable higher-quality conversations within and across scales and within and between levels. Six case studies from the Mekong Region are examined. We find evidence that scale and level politics affects the context, process, content, and outcomes of deliberative engagement in a region where public deliberation is still far from being a norm, particularly where there are sensitive and far-reaching choices to be made about water use and energy production.  相似文献   
205.
Work-contingent self-esteem (WCSE; the degree to which workers' self-esteem is based on workplace performance) has positive consequences for performance, yet less is known about its consequences for well-being. In this paper, we contribute to the literature on WCSE by examining the mechanisms through which it impacts well-being at work and outside of work. We challenge contingent self-esteem (CSE) theory (Crocker & Park, 2004), which argues that CSE negatively impacts well-being by fostering internally controlled (introjected) motivation and diminishing autonomous motivation, by suggesting that WCSE fosters autonomous and internally controlled motivation and thus has both beneficial and harmful effects on well-being. We also expand CSE theory by suggesting that WCSE can negatively impact well-being outcomes by causing work–nonwork conflict. Results from a time-separated design in a sample of full-time employees supported our arguments, revealing that WCSE impacted well-being at work through both autonomous and internally controlled work motivations. WCSE also had negative effects on well-being at and outside of work through work–nonwork conflict. The beneficial effects of WCSE outweighed its harmful effects on job satisfaction and neutralized its harmful effects for all other outcomes. We discuss theoretical implications for CSE theory, self-determination theory, and work–nonwork issues and note important practical implications.  相似文献   
206.
This study aimed at relating the variability of Ni biogeochemistry along the ultramafic toposequence to pedogenesis and soil mineralogy. Hypereutric Cambisols dominate upslope; Cambic Vertisols and Fluvic Cambisols occur downslope. The soil mineralogy showed abundance of primary serpentine all over the sequence. It is predominant upslope but secondary smectites dominate in the Vertisols. Free Fe-oxides are abundant in all soils but slightly more abundant in the upslope soils. Whereas serpentines hold Ni in a similar and restricted range in every soil (approx. 0.3 %), Ni contents in smectites may vary a lot and Mg-rich and Al-poor smectites in the Vertisol could hold up to 4.9 % Ni. Ni was probably adsorbed onto amorphous Fe-oxides and was also exchangeable in secondary smectites. High availability of Ni in soils was confirmed by DTPA extractions. However, it varied significantly along the toposequence, being higher in upslope soils, where Ni-bearing amorphous Fe-oxides were abundant and total organic carbon higher and sensibly lower downslope on the Vertisols: NiDTPA varied from 285 mg kg?1 in the surface of soil I (upslope) to 95.9 mg kg?1 in the surface of Fluvic Cambisols. Concentration of Ni in Alyssum murale shoots varied from 0.7 % (Hypereutric Cambisols) to 1.4 % (Hypereutric Vertisol). Amazingly, Ni uptake by A. murale was not correlated to NiDTPA, suggesting the existence of specific edaphic conditions that affect the ecophysiology of A. murale upslope.  相似文献   
207.
Natural protected areas (NPA) are portions of the Mexican territory where the original environment has not been modified and which are protected in order t  相似文献   
208.
Unlike conventional pollutants, pharmaceutical residues are continuously discharged at low levels (low to mid ng l?1 concentrations), which results in the chronic contamination of non-target organisms, but little is known about the effects of these residues. The purpose of this study was to provide the first assessment of the ecotoxicity of five antidepressants (selective serotonin reuptake inhibitors [SSRIs] fluoxetine and sertraline, tricyclic antidepressants [TCAs] clomipramine and amitriptyline, and serotonin norepinephrine reuptake inhibitor [SNRI] duloxetine) at a wide range of concentrations from 0.1 to 100,000 μg l?1 on two early life stages in the Pacific oyster. The toxicity was quantified in D-shaped larvae after 36 h of exposure, and in 21-day-old pediveliger larvae after 24 h of exposure using the percentage of normal larval development and the metamorphosis rate as endpoints, respectively. The embryotoxicity assays reported that the EC50 values were within the same range of concentrations (67 to 192 μg l?1) for all of the tested molecules. The metamorphosis tests revealed that the antidepressants can be ranked along an increasing severity gradient: clomipramine < amitriptyline < duloxetine ~ fluoxetine. Sertraline appeared to be the less toxic molecule on this endpoint; however, a different concentration range was used. The embryotoxicity test was more sensitive than the metamorphosis bioassay for three of the five molecules tested, but the latter test showed more practical benefits. Overall, the obtained toxicity values were at least 10,000-fold higher than the reported environmental concentrations.  相似文献   
209.
The information presented in this paper is directed to those with the responsibility of designing and operating air quality monitoring networks. An analytical model for location of monitor sites based upon maximizing a sum of coverage factors for each source is developed. An heuristic solution method from the facilities location analysis literature is used for solution of the model. Results of an example problem are presented and compared with the monitoring network currently In place. The model is shown to be a valuable addition to the methods available to the air quality monitor network designer. Needs for further research are pointed out.  相似文献   
210.
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