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981.
An Operational Model for Implementing Conservation Action 总被引:10,自引:0,他引:10
982.
Karen Fisher-Vanden Karin S. Thorburn 《Journal of Environmental Economics and Management》2011,62(3):430-445
Researchers debate whether environmental investments reduce firm value or actually improve financial performance. We provide some compelling evidence on shareholder wealth effects of membership in voluntary environmental programs (VEPs). Companies announcing membership in EPA's Climate Leaders, a program targeting reductions in greenhouse gas emissions, experience significantly negative abnormal stock returns. The price decline is larger in firms with poor corporate governance structures, and for high market-to-book (i.e., high growth) firms. However, firms joining Ceres, a program involving more general environmental commitments, have insignificant announcement returns, as do portfolios of industry rivals. Overall, corporate commitments to reduce greenhouse gas emissions appear to conflict with firm value maximization. This has important implications for policies that rely on voluntary initiatives to address climate change. Further, we find that firms facing climate-related shareholder resolutions or firms with weak corporate governance standards – giving managers the discretion to make such voluntary environmentally responsible investment decisions – are more likely to join Climate Leaders; decisions that may result in lower firm value. 相似文献
983.
ERIC J. WARD BRICE X. SEMMENS ELIZABETH E. HOLMES KEN C. BALCOMB III 《Conservation biology》2011,25(2):350-355
Abstract: Identifying how social organization shapes individual behavior, survival, and fecundity of animals that live in groups can inform conservation efforts and improve forecasts of population abundance, even when the mechanism responsible for group‐level differences is unknown. We constructed a hierarchical Bayesian model to quantify the relative variability in survival rates among different levels of social organization (matrilines and pods) of an endangered population of killer whales (Orcinus orca). Individual killer whales often participate in group activities such as prey sharing and cooperative hunting. The estimated age‐specific survival probabilities and survivorship curves differed considerably among pods and to a lesser extent among matrilines (within pods). Across all pods, males had lower life expectancy than females. Differences in survival between pods may be caused by a combination of factors that vary across the population's range, including reduced prey availability, contaminants in prey, and human activity. Our modeling approach could be applied to demographic rates for other species and for parameters other than survival, including reproduction, prey selection, movement, and detection probabilities. 相似文献
984.
R. S. STENECK T. P. HUGHES J. E. CINNER W. N. ADGER S. N. ARNOLD F. BERKES S. A. BOUDREAU K. BROWN C. FOLKE L. GUNDERSON P. OLSSON M. SCHEFFER E. STEPHENSON B. WALKER J. WILSON B. WORM 《Conservation biology》2011,25(5):904-912
Abstract: Unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. This lack of diversity may increase risks of ecological and economic disruptions. Centuries of intense fishing have extirpated most apex predators in the Gulf of Maine (United States and Canada), effectively creating an American lobster (Homarus americanus) monoculture. Over the past 20 years, the economic diversity of marine resources harvested in Maine has declined by almost 70%. Today, over 80% of the value of Maine's fish and seafood landings is from highly abundant lobsters. Inflation‐corrected income from lobsters in Maine has steadily increased by nearly 400% since 1985. Fisheries managers, policy makers, and fishers view this as a success. However, such lucrative monocultures increase the social and ecological consequences of future declines in lobsters. In southern New England, disease and stresses related to increases in ocean temperature resulted in more than a 70% decline in lobster abundance, prompting managers to propose closing that fishery. A similar collapse in Maine could fundamentally disrupt the social and economic foundation of its coast. We suggest the current success of Maine's lobster fishery is a gilded trap. Gilded traps are a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences. Large financial gain creates a strong reinforcing feedback that deepens the trap. Avoiding or escaping gilded traps requires managing for increased biological and economic diversity. This is difficult to do prior to a crisis while financial incentives for maintaining the status quo are large. The long‐term challenge is to shift fisheries management away from single species toward integrated social‐ecological approaches that diversify local ecosystems, societies, and economies. 相似文献
985.
This study compared the actual and perceived social norms regarding road crossing behaviors, and aimed at uncovering a misperception of group norms. The basic notion underlying the study was that if children perceived the behaviors and attitudes of their friends regarding road crossing as more negative than they actually are, this might lead the children to adopt riskier behavior when crossing the road. The participants were comprised of 123 elementary school children (ages from 6 to 13; 78 boys - 65% and 42 girls - 35%) from Beitar-Ilit, a religious city in Israel. A questionnaire especially constructed for the study was administered to the participants. A t-test yielded a significant difference between the child’s own attitudes score and the perceived peers’ attitudes score. On average, children perceive their friends’ attitudes with regard to road crossing behaviors as being more negative compared to their own attitudes. A second t-test yielded a significant difference between the child’s own behavior score and the perceived peers’ behavior score. Children perceived the road crossing behavior of their friends as riskier relative to their own crossing behavior. A regression test revealed that the variables, perceived peers’ attitudes and perceived peers’ behaviors, contributed significantly to the explained variance: the more risky the perceived peers’ attitudes and behaviors with regard to road crossing, the more risky the child’s own behavior when crossing the road. It is hoped that an interventional educational program based on positive norms in the social group will encourage children to exhibit safe behavior in the roads. 相似文献
986.
Individuals often identify with groups in order to either reduce perceived uncertainty or to feel better about who they are as individuals. This suggests that cognitive and affective identification are two distinctive forms of social identification in organizational settings. Because neurotic individuals are highly motivated to reduce perceived uncertainty, they will tend to identify cognitively with groups. Extraverted individuals, on the other hand, are highly motivated to enhance how they feel about themselves and thus identify affectively with groups. Across three studies, we develop measures of cognitive and affective identification and then show that neuroticism is positively related to cognitive identification, whereas extraversion is positively related to affective identification. We also find that affective identification provides incremental predictive validity over and above cognitive identification in the prediction of organizational commitment, organizational involvement, and organizational citizenship behaviors. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
987.
We examined the role of social embeddedness in creating positive perceptions of organizational support among managerial and staff employees (n = 72) of a large manufacturing firm. We operationalized social embeddedness as the size, density, and quality of employees' networks of multiplex, reciprocated exchange relationships with colleagues. After controlling for support from supervisors and upper management, we found all three aspects of social embeddedness to be associated with perceived organizational support (POS). This research suggests that in addition to the top‐down influence of the organizational hierarchy, POS results from the organizational community within which employees are embedded through their social network in the workplace. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
988.
为探索高危岗位矿工工作倦怠形成机制,寻求合理的干预对策,在文献研究和实地调研基础上,提出矿工工作倦怠假设模型。采用多阶段分层随机抽样法,对1 800名高危岗位矿工进行问卷调查,并借助结构方程模型(SEM)技术验证假设模型。研究表明:组织管理和角色压力均正向影响工作倦怠,工作特征仅正向影响生理疲乏;社会支持是工作压力源到工作倦怠的中介变量;消极应对是工作压力源到工作倦怠的部分中介变量,其中介效应较社会支持大很多;工作压力源通过影响社会支持再影响应对方式进而正向影响工作倦怠。通过有效干预组织管理和角色压力可减缓工作倦怠。 相似文献
989.
990.
Jonathan R. Rhodes Angela M. Guerrero Örjan Bodin Iadine Chadès 《Conservation biology》2020,34(6):1463-1472
As declines in biodiversity accelerate, there is an urgent imperative to ensure that every dollar spent on conservation counts toward species protection. Systematic conservation planning is a widely used approach to achieve this, but there is growing concern that it must better integrate the human social dimensions of conservation to be effective. Yet, fundamental insights about when social data are most critical to inform conservation planning decisions are lacking. To address this problem, we derived novel principles to guide strategic investment in social network information for systematic conservation planning. We considered the common conservation problem of identifying which social actors, in a social network, to engage with to incentivize conservation behavior that maximizes the number of species protected. We used simulations of social networks and species distributed across network nodes to identify the optimal state-dependent strategies and the value of social network information. We did this for a range of motif network structures and species distributions and applied the approach to a small-scale fishery in Kenya. The value of social network information depended strongly on both the distribution of species and social network structure. When species distributions were highly nested (i.e., when species-poor sites are subsets of species-rich sites), the value of social network information was almost always low. This suggests that information on how species are distributed across a network is critical for determining whether to invest in collecting social network data. In contrast, the value of social network information was greatest when social networks were highly centralized. Results for the small-scale fishery were consistent with the simulations. Our results suggest that strategic collection of social network data should be prioritized when species distributions are un-nested and when social networks are likely to be centralized. 相似文献