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201.
Authentic leadership has received considerable attention and research support over the past decade. Now the time has come to refine and better understand how it impacts performance. This study investigates the moderating role followers' positive psychological capital (PsyCap) and the mediating role that leader–member exchange (LMX) may play in influencing the relationship between authentic leadership and followers' performance. Specifically, we tested this mediated moderation model with matched data from 794 followers and their immediate leaders. We found that authentic leadership is positively related to LMX and consequently followers' performance, and to a larger degree, among followers who have low rather than high levels of PsyCap. Our discussion highlights the benefits of understanding the roles of relational processes and followers' positive psychological resources involved in the effectiveness of authentic leadership and how they can be practically implemented. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
202.
Management strategies to reduce the risks to human life and property from wildfire commonly involve burning native vegetation. However, planned burning can conflict with other societal objectives such as human health and biodiversity conservation. These conflicts are likely to intensify as fire regimes change under future climates and as growing human populations encroach farther into fire‐prone ecosystems. Decisions about managing fire risks are therefore complex and warrant more sophisticated approaches than are typically used. We applied a multicriteria decision making approach (MCDA) with the potential to improve fire management outcomes to the case of a highly populated, biodiverse, and flammable wildland–urban interface. We considered the effects of 22 planned burning options on 8 objectives: house protection, maximizing water quality, minimizing carbon emissions and impacts on human health, and minimizing declines of 5 distinct species types. The MCDA identified a small number of management options (burning forest adjacent to houses) that performed well for most objectives, but not for one species type (arboreal mammal) or for water quality. Although MCDA made the conflict between objectives explicit, resolution of the problem depended on the weighting assigned to each objective. Additive weighting of criteria traded off the arboreal mammal and water quality objectives for other objectives. Multiplicative weighting identified scenarios that avoided poor outcomes for any objective, which is important for avoiding potentially irreversible biodiversity losses. To distinguish reliably among management options, future work should focus on reducing uncertainty in outcomes across a range of objectives. Considering management actions that have more predictable outcomes than landscape fuel management will be important. We found that, where data were adequate, an MCDA can support decision making in the complex and often conflicted area of fire management.  相似文献   
203.
For species at risk of decline or extinction in source–sink systems, sources are an obvious target for habitat protection actions. However, the way in which source habitats are identified and prioritized can reduce the effectiveness of conservation actions. Although sources and sinks are conceptually defined using both demographic and movement criteria, simplifications are often required in systems with limited data. To assess the conservation outcomes of alternative source metrics and resulting prioritizations, we simulated population dynamics and extinction risk for 3 endangered species. Using empirically based habitat population models, we linked habitat maps with measured site‐ or habitat‐specific demographic conditions, movement abilities, and behaviors. We calculated source–sink metrics over a range of periods of data collection and prioritized consistently high‐output sources for conservation. We then tested whether prioritized patches identified the habitats that most affected persistence by removing them and measuring the population response. Conservation decisions based on different source–sink metrics and durations of data collection affected species persistence. Shorter time series obscured the ability of metrics to identify influential habitats, particularly in temporally variable and slowly declining populations. Data‐rich source–sink metrics that included both demography and movement information did not always identify the habitats with the greatest influence on extinction risk. In some declining populations, patch abundance better predicted influential habitats for short‐term regional persistence. Because source–sink metrics (i.e., births minus deaths; births and immigrations minus deaths and emigration) describe net population conditions and cancel out gross population counts, they may not adequately identify influential habitats in declining populations. For many nonequilibrium populations, new metrics that maintain the counts of individual births, deaths, and movement may provide additional insight into habitats that most influence persistence.  相似文献   
204.
Translocation, introduction, reintroduction, and assisted migrations are species conservation strategies that are attracting increasing attention, especially in the face of climate change. However, preventing the extinction of the suite of dependent species whose host species are threatened is seldom considered, and the effects on dependent species of moving threatened hosts are unclear. There is no published guidance on how to decide whether to move species, given this uncertainty. We examined the dependent-host system of 4 disparate taxonomic groups: insects on the feather-leaf banksia (Banksia brownii), montane banksia (B. montana), and Stirling Range beard heath (Leucopogon gnaphalioides); parasites of wild cats; mites and ticks on Duvaucel's gecko (Hoplodactylus duvaucelii) and tuatara (Sphenodon punctatus); and internal coccidian parasites of Cirl Bunting (Emberiza cirlus) and Hihi (Notiomystis cincta). We used these case studies to demonstrate a simple process for use in species- and community-level assessments of efforts to conserve dependents with their hosts. The insects dependent on Stirling Range beard heath and parasites on tigers (Panthera tigris) appeared to represent assemblages that would not be conserved by ex situ host conservation. In contrast, for the cases of dependent species we examined involving a single dependent species (internal parasites of birds and the mite Geckobia naultina on Duvaucel's gecko), ex situ conservation of the host species would also conserve the dependent species. However, moving dependent species with their hosts may be insufficient to maintain viable populations of the dependent species, and additional conservation strategies such as supplementing populations may be needed.  相似文献   
205.
We present three studies providing an increased understanding of the interdependence between perceived organizational support (POS) and leader–member exchange (LMX). Using employees from a social service agency and new hires from a variety of organizations, we report evidence for a relational chain leading from supervisors' perceptions of support by the organization (supervisor POS) to the formation of high‐quality LMX relationships with their subordinates (first link), who interpret high‐quality LMX as support from the organization (subordinate POS, second link) and, ultimately, repay the organization with increased dedication and effort (examined here in terms of reduced withdrawal behavior). The relationship between supervisor POS and LMX with subordinates was strongly moderated by supervisor fear of exploitation in exchange relationships (reciprocation wariness), holding only for supervisors with low reciprocation wariness. Consistent with the view that employees perceive the organization as partly responsible for treatment received from supervisors, LMX was found to be more strongly related to POS when employees highly identified their supervisors with the organization (supervisor's organizational embodiment), and this interaction extended to reduced withdrawal behavior. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
206.
In this study, we assess a multilevel approach to work interference with family (WIF) by examining the influence of unit‐level work–family climate, as well as the importance of supervisors' spoken guidance and their behavioral integrity in helping employees process social information about work–family issues. We propose that there are two important ways in which supervisors may influence their subordinates' WIF—through their spoken guidance regarding managing work–family conflict and through their behavioral integrity—employee perceptions of the degree to which supervisors' spoken work–family guidance aligns with their behaviors to help employees manage work and family on the job. Results from a sample of 628 employees of a health system, using path analytic tests of moderated mediation, provide support for the mediated effect of family‐supportive climate on employee work–family conflict (through supervisory work–family guidance) and for a second‐stage moderation in which the effect of guidance on WIF is stronger (weaker) when employees perceive high (low) levels of supervisor work–family behavioral integrity. We discuss the implications of these findings for the study of family‐supportive work environments and work–family conflict. Limitations of this study and directions for future research are also presented. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
207.
Today's hourly workers are facing revised work schedules and shifting hours, which may have critical implications for employment relationships. This study considers the impact of work‐hours fit on key attitudes of hourly employees—perceived organizational support, job stress, work–family conflict, intent to turnover, and life satisfaction. We define work‐hours fit as the difference between an employee's desired number of hours and the actual hours worked, and we examine both the congruence of work‐hours fit and the degree of misfit. We also examine the moderating impact of the type of misfit, defined as working too many versus too few hours. Results indicate that, in our sample, hourly employees are typically not working the hours they prefer. As predicted, work‐hours fit impacts the attitudes we examined, and, when considering the type of misfit, congruence matters more for life satisfaction and intent to turnover. Results also indicate working too few hours impacts job stress and life satisfaction, whereas working too many effects work–family conflict. This paper demonstrates the importance of preferences, as a reflection of time/money resource trade‐offs, and offers ways for employers to improve work–family facilitation and strengthen their employment relationships. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
208.
Analyzing additional data from a longitudinal field experiment, the present research investigate whether pre‐training perceived social self‐efficacy (PSSE) may moderate cross‐cultural training effectiveness. On the basis of the interactionist perspective, we hypothesized that sojourners with high pre‐training PSSE would benefit more from a cross‐cultural coping orientation program, called “Realistic Orientation Program for Entry Stress” (ROPES), than sojourners with low pre‐training PSSE. As a result, the treatment effects (the ROPES program over the control program—a traditional cross‐cultural orientation program) would be more positive for high‐PSSE sojourners than for low‐PSSE sojourners. Seventy‐two incoming graduate students from East Asia entering a large US public university were randomly assigned to either a ROPES program or a control program, and were assessed pre‐entry and multiple times post‐entry. The results strongly supported our predictions, as the hypothesized PSSE × Treatment interactions were observed on a comprehensive set of training outcomes based on multisource data. Theoretical and practical implications were discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
209.
We coupled rainfall–runoff and instream water quality models to evaluate total suspended solids (TSS) in Wissahickon Creek, a mid‐sized urban stream near Philadelphia, Pennsylvania. Using stormwater runoff and instream field data, we calibrated the model at a subdaily scale and focused on storm responses. We demonstrate that treating event mean concentrations as a calibration parameter rather than a fixed input can substantially improve model performance. Urban stormwater TSS concentrations vary widely in time and space and are difficult to represent simply. Suspended and deposited sediment pose independent stressors to stream biota and model results suggest that both currently impair stream health in Wissahickon Creek. Retrofitting existing detention basins to prioritize infiltration reduced instream TSS loads by 20%, suggesting that infiltration mitigates sediment more effectively than detention. Infiltrating stormwater from 30% of the watershed reduced instream TSS loads by 47% and cut the frequency of TSS exceeding 100 mg/L by half. Settled loads and the frequency of high TSS values were reduced by a smaller fraction than suspended loads and duration at high TSS values. A widely distributed network of infiltration‐focused projects is an effective stormwater management strategy to mitigate sediment stress. Coupling rainfall–runoff and water quality models is an important way to integrate watershed‐wide impacts and evaluate how management directly affects urban stream health.  相似文献   
210.
The contents of 90Sr and 137Cs and the pattern of their redistribution in the soil and plant cover of floodplain ecosystems have been assessed. It is shown that the radionuclide distribution across the floodplain and along the river flow is determined by the formation of a barrier to their migration near the river channel, at which less mobile 137Cs accumulates. The soil and plant cover of the central floodplain are enriched with 90Sr. Differences in radionuclide migration in floodplain soils and their input into plants are determined by the relationship between the processes of their immobilization and migration with soil water.  相似文献   
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