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261.
Veríssimo  Diogo  Anderson  Sean  Tlusty  Michael 《Ambio》2020,49(4):903-911

Representations of wildlife in television and films have long been hypothesized to shape human-wildlife interactions. A recent example is Pixar’s film Finding Dory, which featured a blue tang fish (Paracanthurus hepatus) as the main character and was widely reported in the popular press to have increased the number of such fish in the pet trade. We use Bayesian posterior predictive counterfactual models to evaluate the movie’s effect on three metrics of societal behaviour. Although there was an increase in global online searches for the blue tang 2–3 weeks after the movie, we find no substantial evidence for an increase in imports of blue tang fish into the US, or in number of visitors to US aquaria compared to counterfactual expectations. It is vital that an evidence-based discourse is used when communicating potential impacts of popular culture on human-wildlife relationships to avoid loss of credibility and misdirection of conservation resources.

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This paper presents and tests a model of the impact of secure and insecure attachment styles (secure, counterdependent, and overdependent) on citizenship behavior and workplace deviance behavior through vigor at work. Employees who exhibit secure attachment styles are proposed to exhibit more vigor at work because of more effective use of physical, emotional, and cognitive resources which translates into increased organizational citizenship behaviors (OCBs) and decreased deviance. Insecurely attached employees are hypothesized to exhibit the opposite pattern. In a sample of 331 repair generalists in a large building facilities and maintenance organization, results indicate that attachment styles indirectly predicted OCBs and deviance through vigor. Implications of these results for attachment style, vigor at work, OCBs, and deviance are discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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265.
The Sand Hills subdivision of the Southeastern Plains ecoregion has been impacted by historical land uses over the past two centuries and, with the additive effects of contemporary land use, determining reference condition for streams in this region is a challenge. We identified reference condition based on the combined use of 3 independent selection methods. Method 1 involved use of a multivariate disturbance gradient derived from several stressors, method 2 was based on variation in channel morphology, and method 3 was based on passing 6 of 7 environmental criteria. Sites selected as reference from all 3 methods were considered primary reference, whereas those selected by 2 or 1 methods were considered secondary or tertiary reference, respectively. Sites not selected by any of the methods were considered non-reference. In addition, best professional judgment (BPJ) was used to exclude some sites from any reference class, and comparisons were made to examine the utility of BPJ. Non-metric multidimensional scaling indicated that use of BPJ may help designate non-reference sites when unidentified stressors are present. The macroinvertebrate community measures Ephemeroptera, Plecoptera, Trichoptera richness and North Carolina Biotic Index showed no differences between primary and secondary reference sites when BPJ was ignored. However, there was no significant difference among primary, secondary, and tertiary reference sites when BPJ was used. We underscore the importance of classifying reference conditions, especially in regions that have endured significant anthropogenic activity. We suggest that the use of secondary reference sites may enable construction of models that target a broader set of management interests.  相似文献   
266.
Visual‐based rapid assessment techniques provide an efficient method for characterizing the restoration potential of streams, with many focusing on channel stability and instream habitat features. Few studies, however, have compared these techniques to see if they result in differing restoration priorities. Three rapid assessment techniques were contrasted at three wild trout streams in western New York with different amounts of channel disturbance. Two methods focused only on geomorphic stability, whereas the third addressed physical habitat condition. Habitat assessment scores were not correlated with scores for either geomorphic assessment method and they varied more between channels with different degrees of disturbance. A model based on dynamic equilibrium concepts best explains the variation among the streams and techniques because it accounts for a stream's capacity to maintain ecological integrity despite some inherent instability. Geomorphic indices can serve as effective proxies for biological indices in highly disturbed systems. Yet, this may not be the case in less disturbed systems, where geomorphic indices cannot differentiate channel adjustments that impact biota from those that do not. Dynamically stable streams can include both stable and unstable reaches locally as characterized by geomorphic methods and translating these results into restoration priorities may not be appropriate if interpretations are limited to the reach scale.  相似文献   
267.
Abstract: Marine reserves have been suggested as tools for assisting the management of fisheries by protecting vulnerable marine species from overexploitation. Although there is a theoretical basis for believing that marine reserves may serve as management tools, there are few marine reserves in the world in which to test their effectiveness. My research evaluated three forms of marine reserve on the south coast of Vancouver Island, British Columbia, Canada. I used northern abalone ( Haliotis kamtschatkana ), a severely depleted shellfish in this region, as an indicator of the effectiveness of the reserves. Abalone populations in eight sites receiving different degrees of spatial protection were counted and measured in situ during the spring of 1996 and 1997. In all sites with enforced harvest closures, populations of abalone were greater, and one site with nearly 40 years of protection had on average much larger (older) abalone. Reproductive output, as a function of abundance and size, was also greater in the enforced reserve areas. Larval dispersal from reserves, and hence the benefit to exploited areas, was not formally surveyed. Nevertheless, the results of my study, combined with knowledge of present abalone populations, life history, and regional hydrodynamics, suggest that establishment of reserves is justified in the absence of perfect knowledge of larval dispersal.  相似文献   
268.
Urbanization often alters catchment storm responses, with a broad range of potentially significant environmental and engineering consequences. At a practical, site-specific management level, efficient and effective assessment and control of such downstream impacts requires a technical capability to rapidly identify development-induced storm hydrograph changes. The method should also speak specifically to alteration of internal watershed dynamics, require few resources to implement, and provide results that are intuitively accessible to all watershed stakeholders. In this short paper, we propose a potential method which might satisfy these criteria. Our emphasis lies upon the integration of existing concepts to provide tools for pragmatic, relatively low-cost environmental monitoring and management. The procedure involves calibration of rainfall-runoff time-series models in each of several successive time windows, which sample varying degrees of watershed urbanization. As implemented here, only precipitation and stream discharge or stage data are required. The readily generated unit impulse response functions of these time-series models might then provide a mathematically formal, yet visually based and intuitive, representation of changes in watershed storm response. Nominally, the empirical response functions capture such changes as soon as they occur, and the assessments of storm hydrograph alteration are independent of variability in meteorological forcing. We provide a preliminary example of how the technique may be applied using a low-order linear ARX model. The technique may offer a fresh perspective on such watershed management issues, and potentially also several advantages over existing approaches. Substantial further testing is required before attempting to apply the concept as a practical environmental management technique; some possible directions for additional work are suggested.  相似文献   
269.
Pine–oak forests are of high ecological importance worldwide, but many are threatened by uncharacteristically severe wildfire. Forest restoration treatments, including the reintroduction of a surface fire regime, are intended to decrease fire hazard and emulate historic ecosystem structure and function. Restoration has recently received much management attention and short-term study, but little is known about longer-term ecosystem responses. We remeasured a replicated experimental restoration site in the southwestern United States 5 years after treatments. Basal area, tree density, and canopy cover decreased in the treated units at a faster rate than in controls. Delayed mortality, not evident right after treatment, decreased density modestly (13% in treated units and 10% in controls) but disproportionately affected large trees (“large” ponderosa pines were those with diameter at breast height [dbh] ≥37.5 cm; other species dbh ≥20 cm). In treated units, 10.9 large trees ha–1 died, whereas 6.2 trees ha–1 died in control units. Compared with reference conditions, the experimental blocks remained higher in pine density and, in three of the four blocks, in basal area. Pine trees grew significantly faster in treated units than in controls, enough to reach the reference level of basal area in 6 years. Although mortality of large trees is a concern, the treated units have vigorous growth and low density, indicating that they will be relatively resistant to future drought and fire events. Similar treatments may be beneficial in many areas of the United States and in related pine-oak ecosystems elsewhere.  相似文献   
270.

Introduction

Accident data for 2003-2007 indicate that slip, trip, and falls (STFs) are the second leading accident class (17.8%, n = 2,441) of lost-time injuries in underground mining. Proper lighting plays a critical role in enabling miners to detect STF hazards in this environment. Often, the only lighting available to the miner is from a cap lamp worn on the miner's helmet. The focus of this research was to determine if the spectral content of light from light-emitting diode (LED) cap lamps enabled visual performance improvements for the detection of tripping hazards as compared to incandescent cap lamps that are traditionally used in underground mining. A secondary objective was to determine the effects of aging on visual performance.

Method

The visual performance of 30 subjects was quantified by measuring each subject's speed and accuracy in detecting objects positioned on the floor both in the near field, at 1.83 meters, and far field, at 3.66 meters. Near field objects were positioned at 0 degrees and ± 20 degrees off axis, while far field objects were positioned at 0 degrees and ± 10 degrees off axis. Three age groups were designated: group A consisted of subjects 18 to 25 years old, group B consisted of subjects 40 to 50 years old, and group C consisted of subjects 51 years and older.

Results

Results of the visual performance comparison for a commercially available LED, a prototype LED, and an incandescent cap lamp indicate that the location of objects on the floor, the type of cap lamp used, and subject age all had significant influences on the time required to identify potential trip hazards. The LED-based cap lamps enabled detection times that were an average of 0.96 seconds faster compared to the incandescent cap lamp. Use of the LED cap lamps resulted in average detection times that were about 13.6% faster than those recorded for the incandescent cap lamp. The visual performance differences between the commercially available LED and prototype LED cap lamp were not statistically significant.

Impact on Industry

It can be inferred from this data that the spectral content from LED-based cap lamps could enable significant visual performance improvements for miners in the detection of trip hazards.  相似文献   
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