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401.
We investigate how gender harassment affects the romantic relationships (i.e., romantic relationship adjustment and romantic relationship efficacy) of female targets (spillover effects) and their romantic partners (crossover effects), and what role targets' anger in response to their gender harassment plays in these relationships. We explored these questions using two US samples. Sample 1 comprised 206 females, all of whom provided data on their gender harassment experiences, feelings of anger, and romantic relationship functioning. Sample 2 consisted of 60 romantic dyads. Females once again provided data on their gender harassment experiences and feelings of anger; their romantic partners reported on their own romantic relationship functioning. Full support emerged for hypothesized spillover effects: supervisor gender harassment indirectly and negatively influenced targets' romantic relationship adjustment and romantic relationship efficacy through target anger (Sample 1). Full support also emerged for hypothesized crossover effects: supervisor gender harassment indirectly and negatively influenced the romantic relationship adjustment and romantic relationship efficacy of targets' romantic partners through target anger (Sample 2). Implications for theory, research, and practice are considered. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
402.
The current study examined the effect of employees' perceived overqualification on counterproductive work behaviors (CWBs). Building on person–job fit theory and prior research on such organizational phenomena, we conceptualized overqualification as a type of poor person–job fit. Drawing on the dual‐process model, we further suggested that in processing their person–job misfit, overqualified employees might cognitively appraise themselves as less worthy organizational members and experientially feel angry toward the employment situation. We also suggested that to the extent that overqualified people are sensitive to justice, they may react more or less strongly to being overqualified. We tested our predictions using time‐lagged data from a sample of 224 workers and their supervisors employed in a large manufacturing company in China. Consistent with our theoretical framework, we found that organization‐based self‐esteem (OBSE) and anger toward employment situation mediated the positive relationships between perceived overqualification and both self‐rated and supervisor‐rated CWBs. In addition, justice sensitivity moderated the relationship between perceived overqualification and the mediators (i.e., OBSE and anger) and the indirect relationship between perceived overqualification and CWB. The theoretical and practical implications of these findings as well as future research directions are discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
403.
Biodiversity conservation strategies are increasingly focused on regions outside national protected areas, where animals face numerous anthropogenic threats and must coexist with human settlements, livestock, and agriculture. The effects of these potential threats are not always clear, but they could have profound implications for population viability. We used savannah elephants (Loxodonta africana) as a case study to assess the physiological stress associated with living in a human‐livestock‐dominated landscape. We collected samples over two 3‐month periods in 2007 and 2008. We used fecal DNA to identify 96 individual elephants in a community conservation area (CCA) and measured fecal glucocorticoid metabolite (FGM) concentrations as a proxy for stress. The CCA is community Maasai land managed for livestock and wildlife. We compared the FGM concentrations from the CCA to FGM concentrations of 40 elephants in Amboseli National Park and 32 elephants in the Maasai Mara National Reserve, where human settlements and intense livestock grazing were absent. In the CCA, we found no significant individual differences in FGM concentrations among the elephants in 2007 (p = 0.312) or 2008 (p = 0.412) and no difference between years (p = 0.616). The elephants in the CCA had similar FGM concentrations to the Maasai Mara population, but Amboseli elephants had significantly lower FGM concentrations than those in either Maasai Mara or the CCA (Tukey pairwise test, p < 0.001), due primarily to females excreting significantly lower FGM relative to males (p = 0.025). In the CCA, there was no relation among female group size, average pairwise group relatedness, and average group FGM concentration. We found no clear evidence of chronic stress in elephants living on CCA communal land, which is encouraging for conservation strategies promoting the protection of animals living outside protected areas. Conservación Fuera de Áreas Protegidas y el Efecto de Paisajes Dominados por Humanos sobre Hormonas del Estrés en Elefantes Africanos  相似文献   
404.
This paper examines approaches for local resident participation in community‐based natural resource management (CBNRM); focusing particularly on the potential impacts that local participation imposes on the natural environment. This study used qualitative methods to collect data, and selected Meqmegi, an indigenous community in Taiwan, as a case study. The findings indicate that many opportunities can be created that stimulate a community to participate in natural resource management; moreover, residents are prone to use their own ways to participate. Therefore, although local participation is praised for its people‐oriented way of natural resource management, impacts from the participation process will ultimately be imposed on the environment. We suggest that more consideration be given to the environmental conditions during the process of local participation via CBNRM to make sure that impacts on the environment are positive, and lead to a truly sustainable future.  相似文献   
405.
Abstract: Predation pressure on vulnerable bird species has made predator control an important issue for international nature conservation. Predator removal by culling or translocation is controversial, expensive, and time‐consuming, and results are often temporary. Thus, it is important to assess its effectiveness from all available evidence. We used explicit systematic review methodology to determine the impact of predator removal on four measurable responses in birds: breeding performance (hatching success and fledging success) and population size (breeding and postbreeding). We used meta‐analysis to summarize results from 83 predator removal studies from six continents. We also investigated whether characteristics of the prey, predator species, location, and study methodology explained heterogeneity in effect sizes. Removing predators increased hatching success, fledging success, and breeding populations. Removing all predator species achieved a significantly larger increase in breeding population than removing only a subset. Postbreeding population size was not improved on islands, or overall, but did increase on mainlands. Heterogeneity in effect sizes for the four population parameters was not explained by whether predators were native or introduced; prey were declining, migratory, or game species; or by the study methodology. Effect sizes for fledging success were smaller for ground‐nesting birds than those that nest elsewhere, but the difference was not significant. We conclude that current evidence indicates that predator removal is an effective strategy for the conservation of vulnerable bird populations. Nevertheless, the ethical and practical problems associated with predator removal may lead managers to favor alternative, nonlethal solutions. Research is needed to provide and synthesize data to determine whether these are effective management practices for future policies on bird conservation.  相似文献   
406.
Abstract: One of the most important tools in conservation biology is information on the geographic distribution of species and the variables determining those patterns. We used maximum‐entropy niche modeling to run distribution models for 222 amphibian and 371 reptile species (49% endemics and 27% threatened) for which we had 34,619 single geographic records. The planning region is in southeastern Mexico, is 20% of the country's area, includes 80% of the country's herpetofauna, and lacks an adequate protected‐area system. We used probabilistic data to build distribution models of herpetofauna for use in prioritizing conservation areas for three target groups (all species and threatened and endemic species). The accuracy of species‐distribution models was better for endemic and threatened species than it was for all species. Forty‐seven percent of the region has been deforested and additional conservation areas with 13.7% to 88.6% more native vegetation (76% to 96% of the areas are outside the current protected‐area system) are needed. There was overlap in 26 of the main selected areas in the conservation‐area network prioritized to preserve the target groups, and for all three target groups the proportion of vegetation types needed for their conservation was constant: 30% pine and oak forests, 22% tropical evergreen forest, 17% low deciduous forest, and 8% montane cloud forests. The fact that different groups of species require the same proportion of habitat types suggests that the pine and oak forests support the highest proportion of endemic and threatened species and should therefore be given priority over other types of vegetation for inclusion in the protected areas of southeastern Mexico.  相似文献   
407.
Abstract: Ecosystem management (EM) offers a means to address multiple threats to marine resources. Despite recognition of the importance of stakeholder involvement, most efforts to implement EM in marine systems are the product of top‐down regulatory control. We describe a rare, stakeholder‐driven attempt to implement EM from the bottom up in San Juan County, Washington (U.S.A.). A citizens advisory group led a 2‐year, highly participatory effort to develop an ecosystem‐based management plan, guided by a preexisting conservation‐planning framework. A key innovation was to incorporate social dimensions by designating both sociocultural and biodiversity targets in the planning process. Multiple obstacles hindered implementation of EM in this setting. Despite using a surrogate scheme, the information‐related transaction costs of planning were substantial: information deficits prevented assessment of some biodiversity targets and insufficient resources combined with information deficits prevented scientific assessment of the sociocultural targets. Substantial uncertainty, practical constraints to stakeholder involvement, and the existence of multiple, potentially conflicting, objectives increased negotiation‐related costs. Although information deficits and uncertainty, coupled with underinvestment in the transaction costs of planning, could reduce the long‐term effectiveness of the plan itself, the social capital and momentum developed through the planning process could yield unforeseeable future gains in protection of marine resources. The obstacles we identified here will require early and sustained attention in efforts to implement ecosystem management in other grassroots settings.  相似文献   
408.
Recovery plans for species listed under the U.S. Endangered Species Act are required to specify measurable criteria that can be used to determine when the species can be delisted. For the 642 listed endangered and threatened plant species that have recovery plans, we applied recursive partitioning methods to test whether the number of individuals or populations required for delisting can be predicted on the basis of distributional and biological traits, previous abundance at multiple time steps, or a combination of traits and previous abundances. We also tested listing status (threatened or endangered) and the year the recovery plan was written as predictors of recovery criteria. We analyzed separately recovery criteria that were stated as number of populations and as number of individuals (population‐based and individual‐based criteria, respectively). Previous abundances alone were relatively good predictors of population‐based recovery criteria. Fewer populations, but a greater proportion of historically known populations, were required to delist species that had few populations at listing compared with species that had more populations at listing. Previous abundances were also good predictors of individual‐based delisting criteria when models included both abundances and traits. The physiographic division in which the species occur was also a good predictor of individual‐based criteria. Our results suggest managers are relying on previous abundances and patterns of decline as guidelines for setting recovery criteria. This may be justifiable in that previous abundances inform managers of the effects of both intrinsic traits and extrinsic threats that interact and determine extinction risk. Predicción de Criterios de Recuperación para Especies de Plantas en Peligro y Amenazadas con Base en Abundancias Pasadas y Atributos Biológicos  相似文献   
409.
This article examines whether it is possible to target vulnerable households within a geographically defined area. It looks first at the justification for targeting and then reviews recent practical experience in actually trying to reach vulnerable groups. As complex emergencies increasingly last longer, strategies to target vulnerable households are common in the protracted phase of the emergency. While this is often necessary because of a decline in resources, it is not always justified by an improvement in nutritional status or food security of the beneficiary population.
Common target groups are the poor and the malnourished, but in complex emergencies these are not always the most vulnerable. Moreover, recent practical experience has shown considerable difficulties in targeting the poor. Methods to target the poor rely on community-based relief committees, whose priorities are not necessarily the same as those of external agencies. This paper gives examples of such targeted assistance programmes in Kenya, south Sudan and Tanzania. The paper concludes that situations where targeting vulnerable households is justified and feasible are extremely limited. It is suggested that if targeting has to be done because of scarce resources, this should be done on a geographical basis and on the basis of nutritional status. Case-study material shows that it is essential to understand the political determinants of vulnerability and to design methods that will reach the most vulnerable.  相似文献   
410.
改性矿化垃圾反应床处理填埋场渗滤液研究   总被引:4,自引:0,他引:4  
在固液比(矿化垃圾与废水的质量比)为100,1,运行周期为3 h.水力负荷为0.08 m3/(m3·d)条件下,分别采用废铁屑、钢渣、蘑菇渣、秸秆作为改性材料进行矿化垃圾反应床处理填埋场渗滤液的工艺强化研究.结果表明,废铁屑对COD、色度、总氮和总磷的去除有显著的强化作用,COD、总氮和总磷去除率平均提高9.3%、17%和7.7%;钢渣不利于氨氮和总氮的去除,且需定期置换钢渣以维持其去除COD和总磷的强化作用;蘑菇渣和秸秆均需先进行合适的驯化降解处理,才能实现其去除COD、色度、氨氮和总氮的强化作用.从工程应用角度看,废铁屑是相对理想的一种改性材料.  相似文献   
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