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491.
492.
Mohammad S. Farhadinia Paul J. Johnson Alexandra Zimmermann Philip J.K. McGowan Erik Meijaard Mark Stanley-Price David W. Macdonald 《Conservation biology》2020,34(4):988-996
The persistence of endangered species may depend on the fate of a very small number of individual animals. In situ conservation alone may sometimes be insufficient. In these instances, the International Union for Conservation of Nature provides guidelines for ex situ conservation and the Convention on Biological Diversity (CBD) indicates how ex situ management can support the CBD's objectives by providing insurance policies for species. The circumstances that justify its use are uncertain. To evaluate the current in situ extinction risk and ex situ management of 43 critically endangered species of mammalian megafauna, we used nonmetric multidimensional scaling and geopolitical variables related to governance, economics, and national policy within their extant ranges. We then fitted generalized additive models to assess the contribution of each variable to the ordination. Fifteen (almost one-third) of the world's terrestrial mammalian megafauna are not the subject of any ex situ management. Seventy-three percent of these taxa occur in areas characterized by political uncertainty, such as border zones or areas affected by armed conflicts, mainly in Africa and the Middle East. A further 23% of taxa in ex situ programs do not meet sustainability criteria for inbreeding avoidance. Strategic conservation planning, such as the One Plan approach, may improve ex situ management for these taxa. Given the escalating trend in threats afflicting megafauna, ex situ management should be considered more rigorously, particularly in politically unstable regions, to achieve CBD Target 12 (prevent extinction of threatened species). 相似文献
493.
Stacy A. Lischka Tara L. Teel Heather E. Johnson Courtney Larson Stewart Breck Kevin Crooks 《Conservation biology》2020,34(6):1383-1392
Conflicts between people and wild animals are increasing globally, often with serious consequences for both. Local regulations or ordinances are frequently used to promote human behaviors that minimize these conflicts (risk-reducing behaviors), but compliance with ordinances can be highly variable. While efforts to increase compliance could be improved through applications of conservation psychology, little is known about the relative influence of different factors motivating compliance. Using concepts from psychology and risk theory, we conducted a longitudinal study pairing data from mail surveys with direct observations of compliance with a wildlife ordinance requiring residents to secure residential garbage from black bears (Ursus americanus). We assessed the relative influence of beliefs and attitudes toward bears and bear proofing, perceived behavioral control, perceived risks and benefits assigned to bears, norms, trust in management, previous experience with conflicts, and demographics on compliance behavior (i.e., bear proofing). Data on previous experience were obtained through direct observation and survey reports. We found that higher compliance rates were associated with more observed conflicts on a respondent's block. Counter to expectations, however, residents were less compliant when they were more trusting of the management agency and perceived more benefits from bears. We suggest that messages have the potential to increase compliance when they empower residents by linking successful management of conflicts to individual actions and emphasize how reducing conflicts could maintain benefits provided by wildlife. Modifying existing educational materials to account for these psychological considerations and evaluating their impact on compliance behavior over time are important next steps in changing human behaviors relevant to the globally important problem of human-wildlife conflict. 相似文献
494.
Ross Johnson 《Environmental monitoring and assessment》1993,26(2-3):307-312
Now that the concerns, issues, ideas and constraints have been discussed, how does all of this come together? There are three basic questions we should ask. ? Can we improve natural resource management through monitoring? ? Will those that make the decisions listen? ? Will they use the generated data in their decision? I am going to relate to you what has happened in California over the last fifteen years. I believe it will point out that the answer to the three questions are a resounding yes, with some qualifications and some bumpy roads along the way. 相似文献
495.
Although interest in regulatory focus research continues to grow, there has been very little work to date on the assessment and usefulness of regulatory focus in the workplace. The present research effort reports the results of a series of studies designed to assess the validity and utility of the Regulatory Focus at Work Scale (RWS). The results indicate that the RWS is reliable, valid, and showed incremental validity beyond general and trait‐like measures of regulatory focus in predicting relevant work outcomes of task performance, citizenship performance, safety performance, and productivity performance. The overall results of these studies support our claims that the RWS shows utility in predicting workplace outcomes and should prove useful for future research on regulatory focus in the workplace. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
496.
In the indoor environment, settled surface dust often functions as a reservoir of hazardous particulate contaminants. In many
circumstances, a major contributing source to the dust pool is exterior soil. Young children are particularly susceptible
to exposure to both outdoor derived soil and indoor derived dust present in the indoor dust pool. This is because early in
life the exploratory activities of the infant are dominated by touching and mouthing behavior. Inadvertent exposure to dust
through mouth contact and hand-to-mouth activity is an inevitable consequence of infant development. Clean-up of indoor dust
is, in many circumstances, critically important in efforts to minimize pediatric exposure. In this study, we examine the efficiency
of vacuum cleaner removal of footwear-deposited soil on vinyl floor tiles. The study utilized a 5 × 10 foot (c. 152.5 × 305 cm)
test surface composed of 1-foot-square (c. 30.5 × 30.5 cm) vinyl floor tiles. A composite test soil with moderately elevated
levels of certain elements (e.g., Pb) was repeatedly introduced onto the floor surface by footwear track-on. The deposited
soil was subsequently periodically removed from randomly selected tiles using a domestic vacuum cleaner. The mass and loading
of soil elements on the tiles following vacuuming were determined both by wet wipe collection and by subsequent chemical analysis.
It was found that vacuum cleaner removal eliminated much of the soil mass from the floor tiles. However, a small percentage
of the mass was not removed and a portion of this residual mass could be picked up by moistened hand-lifts. Furthermore, although
the post-vacuuming tile soil mass was sizably reduced, for some elements (notably Pb) the concentration in the residual soil
was increased. We interpret this increased metal concentration to be a particle size effect with smaller particles (with a
proportionately higher metal content) remaining in situ after vacuuming. 相似文献
497.
Human activities release tremendous amounts of nitrogenous compounds into the atmosphere. Wet and dry deposition distributes this airborne nitrogen (N) on otherwise pristine ecosystems. This eutrophication process significantly alters the species composition of native grasslands; generally a few nitrophilic plant species become dominant while many other species disappear. The functional equilibrium model predicts that, compared to species that decline in response to N enrichment, nitrophilic grass species should respond to N enrichment with greater biomass allocation aboveground and reduced allocation to roots and mycorrhizas. The mycorrhizal feedback hypothesis states that the composition of mycorrhizal fungal communities may influence the composition of plant communities, and it predicts that N enrichment may generate reciprocal shifts in the species composition of mycorrhizal fungi and plants. We tested these hypotheses with experiments that compared biomass allocation and mycorrhizal function of four grass ecotypes (three species), two that gained and two that lost biomass and cover in response to long-term N enrichment experiments at Cedar Creek and Konza Long-Term Ecological Research grasslands. Local grass ecotypes were grown in soil from their respective sites and inoculated with whole-soil inoculum collected from either fertilized (FERT) or unfertilized (UNFERT) plots. Our results strongly support the functional equilibrium model. In both grassland systems the nitrophilic grass species grew taller, allocated more biomass to shoots than to roots, and formed fewer mycorrhizas compared to the grass species that it replaced. Our results did not fully support the hypothesis that N-induced changes in the mycorrhizal fungal community were drivers of the plant community shifts that accompany N eutrophication. The FERT and UNFERT soil inoculum influenced the growth of the grasses differently, but this varied with site and grass ecotype in both expected and unexpected ways suggesting that ambient soil fertility or other factors may be interacting with mycorrhizal feedbacks. 相似文献
498.
Tracey N. Johnson Patricia L. KennedyTim DelCurto Robert V. Taylor 《Agriculture, ecosystems & environment》2011,144(1):338-346
In 2006-2010, effects of four different cattle stocking rates (0, 14.4, 28.8, and 43.2 animal unit months) were compared, representing 0%, 20%, 32%, and 46% utilization of vegetation by domestic livestock, on vegetation structure (as indexed by visual obstruction), and songbird population and apparent nest density, community composition, and diversity in a Pacific Northwest bunchgrass prairie in northeastern Oregon, USA. Overall paddock-level visual obstruction decreased and structural heterogeneity increased with increasing stocking rates, and those effects carried over 1 year after grazing had ceased. Most species were able to locate nesting sites regardless of differences in visual obstruction, except western meadowlark and vesper sparrow, for which obstruction was lower in paddocks with higher stocking rates. Apparent nest density for grasshopper sparrows was negatively affected by higher stocking rates. Grazing effects on absolute songbird population density were restricted to negative effects of higher stocking rates on savannah sparrows, but this relationship was not observed until 1 year after grazing had ceased. Songbird community composition differed between control and heavily-grazed paddocks, driven by an increase in the proportion of horned larks and a decrease in the proportion of savannah sparrows in heavily-grazed paddocks from pre-treatment to post-treatment years. Bird diversity indices were unaffected by stocking rate. Negative effects of high stocking rates on densities of two species and the absence of any clear positive effect for the other three species suggest high stocking rates as applied in this experiment may not provide suitable habitat for all grassland songbirds. The absence of negative responses of density to low and moderate stocking rates suggests these grazing regimes generally provided suitable habitat for all species. 相似文献
499.
500.
C.W. Johnson 《Safety Science》2011,49(5):735-745
Public and private organisations are investing increasing amounts into the development of healthcare software. These applications are perceived to offer numerous benefits. Software systems can improve the exchange of information between healthcare facilities. They support standardized procedures that can help to increase consistency between different service providers. Electronic patient records ensure minimum standards across the trajectory of care when patients move between different specializations. Healthcare information systems also offer economic benefits through efficiency savings; for example by providing the data that helps to identify potential bottlenecks in the provision and administration of care. However, a number of high-profile failures reveal the safety concerns that arise when staff must cope with the loss of these applications. In particular, teams have to retrieve paper based records that often lack the detail of electronic systems. Individuals who have only used electronic information systems face particular problems in learning how to apply paper-based fallbacks. The following pages compare two different failures of healthcare information systems in the UK and North America. The intention is to ensure that future initiatives to extend the integration of electronic patient records will build on the ‘lessons learned’ from previous systems. 相似文献