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101.
This paper develops and tests hypotheses concerning some psychological correlates of role ambiguity and role conflict in a population that has not been extensively studied in relation to stress, union stewards. Survey data on role ambiguity and role conflict, the indicators of stress, were collected from 285 stewards at the local union steward meeting, with the stewards perceiving a moderate amount of role ambiguity and perceiving a lesser amount of role conflict. The stewards were also asked about their role expectations, their motivations for remaining a steward, their grievance handling strategies, and their affective commitment toward the union and employer. Each of those four sets of variables was hypothesized to be related to role ambiguity and role conflict and each was influential in explaining variance. As predicted, those stewards who were more motivated to remain stewards for personal reasons had both higher role ambiguity and higher role conflict. Further, the conditions of being more motivated to remain a steward to help the union and employees and having higher union commitment were associated with lower role conflict, but, opposite to the hypotheses, higher role ambiguity. 相似文献
102.
The conservation of biodiversity is an important issue world wide and in Australia the maintenance of native biodiversity on farms makes an important contribution to overall conservation objectives. This paper seeks to explain Australian farmers' rationale for maintaining biodiversity on their farms for personal as opposed to business reasons by developing a decision-systems theory from in-depth interviews. This difference has implications for policy development. The decision-systems theory is divided into two main sections. The first section contains five parts. (1) A hierarchy of motivation stories, (2) the concept of suitability and availability of opportunities, (3) a hierarchy of three decision-systems, (4) the concept of personal career paths, (5) the concept of Lenses. The second section contains one part, a policy classification system called 'boxes of influence' that suggests how policy developers can use the information in the first section to develop new biodiversity conservation policy. The paper suggests that decision-systems theory could be used to shed new light on current trends in agriculture and become an important investigative tool for policy development concerning the conservation of biodiversity on farms. 相似文献
103.
Ruth E. Bennett T. Scott Sillett Robert A. Rice Peter P. Marra 《Conservation biology》2022,36(1):e13779
To meet the growing demand for chocolate, cocoa (Theobroma cacao) agriculture is expanding and intensifying. Although this threatens tropical forests, cocoa sustainability initiatives largely overlook biodiversity conservation. To inform these initiatives, we analyzed how cocoa agriculture affects bird diversity at farm and landscape scales with a meta-analysis of 23 studies. We extracted 214 Hedges' g* comparisons of bird diversity and 14 comparisons of community similarity between a forest baseline and 4 farming systems that cover an intensification gradient in landscapes with high and low forest cover, and we summarized 119 correlations between cocoa farm features and bird diversity. Bird diversity declined sharply in low shade cocoa. Cocoa with >30% canopy cover from diverse trees retained bird diversity similar to nearby primary or mature secondary forest but held a different community of birds. Diversity of endemic species, frugivores, and insectivores (agriculture avoiders) declined, whereas diversity of habitat generalists, migrants, nectarivores, and granivores (agriculture associates) increased. As forest decreased on the landscape, the difference in bird community composition between forest and cocoa also decreased, indicating agriculture associates replaced agriculture avoiders in forest patches. Our results emphasize the need to conserve forested landscapes (land sparing) and invest in mixed-shade agroforestry (land sharing) because each strategy benefits a diverse and distinct biological community. 相似文献
104.
Ruth M. Thompson Jordan Hall Chris Morrison Nicole R. Palmer David L. Roberts 《Conservation biology》2021,35(6):1747-1754
Internet-based research is increasingly important for conservation science and has wide-ranging applications and contexts, including culturomics, illegal wildlife trade, and citizen science. However, online research methods pose a range of ethical and legal challenges. Online data may be protected by copyright, database rights, or contract law. Privacy rights may also restrict the use and access of data, as well as ethical requirements from institutions. Online data have real-world meaning, and the ethical treatment of individuals and communities must not be marginalized when conducting internet-based research. As ethics frameworks originally developed for biomedical applications are inadequate for these methods, we propose that research activities involving the analysis of preexisting online data be treated analogous to offline social science methods, in particular, nondeceptive covert observation. By treating internet users and their data with respect and due consideration, conservationists can uphold the public trust needed to effectively address real-world issues. 相似文献
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Polyamines accumulate under various stress conditions in leaves of herbaceous plants. These stress responses, which are related to the physiological functions of polyamines, notably theirmembrane-stabilizing andradical-scavanging effect, are protective measures taken by the plant. Results from several natural spruce stands in Germany indicate that putrescine levels depend on the extent of damage. Needles with early signs of damage and needles with severe damage had significantly higher levels of putrescine than needles of healthy trees. Long-term fumigation of young beech and spruce trees with high concentrations of ozone, SO2, and NOx shows elevated levels of putrescine in leaves and needles. Thus, putrescine content can be used as a stress indicator in the assessment of novel forest damage even at early stages. 相似文献
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Breivik K Alcock R Li YF Bailey RE Fiedler H Pacyna JM 《Environmental pollution (Barking, Essex : 1987)》2004,128(1-2):3-16
During the last decade, a number of studies have been devoted to the sources and emissions of Persistent Organic Pollutants (POPs) at regional and global scales. While significant improvements in knowledge have been achieved for some pesticides, the quantitative understanding of the emission processes and emission patterns for "non-pesticide" POPs are still considered limited. The key issues remaining for the non-pesticide POPs are in part determined by their general source classification. For industrial chemicals, such as the polychlorinated biphenyls (PCBs), there is considerable uncertainty with respect to the relative importance of atmospheric emissions from various source categories. For PCBs, temperature is discussed as a potential key factor influencing atmospheric emission levels and patterns. When it comes to the unintentional by-products of combustion and industrial processes (PCDD/Fs), there is still a large uncertainty with respect to the relative contribution of emissions from unregulated sources such as backyard barrel burning that requires further consideration and characterisation. For hexachlorobenzene (HCB), the relative importance of primary and secondary atmospheric emissions in controlling current atmospheric concentrations remains one of the key uncertainties. While these and other issues may remain unresolved, knowledge concerning the emissions of POPs is a prerequisite for any attempt to understand and predict the distribution and fate of these chemicals on a regional and global scale as well as to efficiently minimise future environmental burdens. 相似文献
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