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The anti-predator responses of an animal may depend on the species of predator attacking. For example, ground-dwelling monkeys
respond with different warning calls in response to attacks from hawks from above vs attacks from leopards at the side. In
grouping animals, it has usually been assumed that the best anti-predator behavior against most predators is to move toward
the center of a group. However, little work has been done to study positioning of individuals in response to different predators
and whether it might be influenced by gender or body condition. An optimality model is developed that gives predictions for
how the needs of predator avoidance, drafting, and foraging could lead to one optimal location within the group. We then conducted
a laboratory experiment with individually marked whirligig beetles (Coleoptera: Gyrinidae). We exposed them to an aerial (bird)
or aquatic (fish) attack and determined changes in their distance to the front of groups at different speeds of water. We
found that female whirligigs occupied the front of a group in response to a fish attack in fast water, but the back after
an aerial bird attack, while the reverse was true for males. In slow water, different results were found; in response to a
bird attack, females were more likely to be found in the front compared with males. Body condition was not correlated to the
front/back position of either males or females before or after attacks in our study. 相似文献
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Sara H. Williams Sarah A. Scriven David F. R. P. Burslem Jane K. Hill Glen Reynolds Agnes L. Agama Frederick Kugan Colin R. Maycock Eyen Khoo Alexander Y. L. Hastie John B. Sugau Reuben Nilus Joan T. Pereira Sandy L. T. Tsen Leung Y. Lee Suzika Juiling Jenny A. Hodgson Lydia E. S. Cole Gregory P. Asner Luke J. Evans Jedediah F. Brodie 《Conservation biology》2020,34(4):934-942
Conservation planning tends to focus on protecting species’ ranges or landscape connectivity but seldom both—particularly in the case of diverse taxonomic assemblages and multiple planning goals. Therefore, information on potential trade-offs between maintaining landscape connectivity and achieving other conservation objectives is lacking. We developed an optimization approach to prioritize the maximal protection of species’ ranges, ecosystem types, and forest carbon stocks, while also including habitat connectivity for range-shifting species and dispersal corridors to link protected area. We applied our approach to Sabah, Malaysia, where the state government mandated an increase in protected-area coverage of approximately 305,000 ha but did not specify where new protected areas should be. Compared with a conservation planning approach that did not incorporate the 2 connectivity features, our approach increased the protection of dispersal corridors and elevational connectivity by 13% and 21%, respectively. Coverage of vertebrate and plant species’ ranges and forest types were the same whether connectivity was included or excluded. Our approach protected 2% less forest carbon and 3% less butterfly range than when connectivity features were not included. Hence, the inclusion of connectivity into conservation planning can generate large increases in the protection of landscape connectivity with minimal loss of representation of other conservation targets. 相似文献
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M. Sandy Hershcovis 《组织行为杂志》2011,32(3):499-519
Research in the field of workplace aggression has rapidly developed in the last two decades, and with this growth has come an abundance of overlapping constructs that fall under the broad rubric of workplace aggression. While researchers have conceptually distinguished these constructs, it is unclear whether this proliferation of constructs is adding appreciably to our knowledge, or whether it is constraining the questions we ask. In this paper, I consider five example constructs (i.e., abusive supervision, bullying, incivility, social undermining, and interpersonal conflict) and argue that the manner in which we have differentiated these (and other) aggression constructs does not add appreciably to our knowledge of workplace aggression. I then provide supplementary meta‐analytic evidence to show that there is not a predictable pattern of outcomes from these constructs, and propose a restructuring of the manner in which we conceptualize workplace aggression. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Huan-fang?Huang Xin-li?XingEmail author Ze-zhou?Zhang Shi-hua?Qi Dan?Yang Dave?A.?Yuen Edward?H.?Sandy Ai-guo?Zhou Xiao-qian?Li 《Environmental geochemistry and health》2016,38(5):1169-1181
Mining activities are among the major culprits of the wide occurrences of soil and water pollution by PAHs in coal district, which have resulted in ecological fragilities and health risk for local residents. Sixteen PAHs in multimedia environment from the Heshan coal district of Guangxi, South China, were measured, aiming to investigate the contamination level, distribution and possible sources and to estimate the potential health risks of PAHs. The average concentrations of 16 PAHs in the coal, coal gangue, soil, surface water and groundwater were 5114.56, 4551.10, 1280.12 ng g?1, 426.98 and 381.20 ng L?1, respectively. Additionally, higher soil and water PAH concentrations were detected in the vicinities of coal or coal gangue dump. Composition analysis, isomeric ratio, Pearson correlation analysis and principal component analysis were performed to diagnose the potential sources of PAHs in different environmental matrices, suggesting the dominant inputs of PAHs from coal/coal combustion and coal gangue in the soil and water. Soil and water guidelines and the incremental lifetime risk (ICLR) were used to assess the health risk, showing that soil and water were heavily contaminated by PAHs, and mean ICLRcoal/coal-gangue and mean ICLRsoil were both significantly higher than the acceptable levels (1 × 10?4), posing high potential carcinogenic risk to residents, especially coal workers. This study highlights the environmental pollution problems and public health concerns of coal mining, particularly the potential occupational health hazards of coal miners exposed in Heshan. 相似文献
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Developing the ethical matrix as a decision support framework: GM fish as a case study 总被引:2,自引:0,他引:2
Matthias Kaiser Kate Millar Erik Thorstensen Sandy Tomkins 《Journal of Agricultural and Environmental Ethics》2007,20(1):65-80
The Ethical Matrix was developed to help decision-makers explore the ethical issues raised by agri-food biotechnologies. Over
the decade since its inception the Ethical Matrix has been used by a number of organizations and the philosophical basis of
the framework has been discussed and analyzed extensively. The role of tools such as the Ethical Matrix in public policy decision-making
has received increasing attention. In order to further develop the methodological aspects of the Ethical Matrix method, work
was carried out to study the potential role of the Ethical Matrix as a decision support framework. When considering which
frameworks to apply when analyzing the ethical dimensions of the application of agri-food biotechnologies, it is important
to clarify the substantive nature of any prospective framework. In order to further investigate this issue, reflections on
the neologism “ethical soundness” of an ethical framework are presented here. This concept is introduced in order to provide
more structured evaluations of a range of ethical tools, including ethical frameworks such as the Ethical Matrix. As well
as examining the philosophical dimensions of the method, theoretical analysis and literature studies were combined with stakeholder
engagement exercises and consultations in order to review the Ethical Matrix from a user perspective. This work resulted in
the development of an Ethical Matrix Manual, which is intended to act as a guide for potential user groups. 相似文献
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Improvements in production methods over the last two decades have resulted in aquaculture becoming a significant contributor
to food production in many countries. Increased efficiency and production levels are off-setting unsustainable capture fishing
practices and contributing to food security, particularly in a number of developing countries. The challenge for the rapidly
growing aquaculture industry is to develop and apply technologies that ensure sustainable production methods that will reduce
environmental damage, increase productivity across the sector, and respect the diverse social and cultural dimensions of fish
farming that are observed globally. The aquaculture industry currently faces a number of technology trajectories, which include
the option to commercially produce genetically modified (GM) fish. The use of genetic modification in aquaculture has the
potential to contribute to increased food security and is claimed to be the next logical step for the industry. However, the
potential use of these technologies raises a number of important ethical questions. Using an ethical framework, the Ethical
Matrix, this paper explores a number of the ethical issues potentially raised by the use of GM technologies in aquaculture.
Several key issues have been identified. These include aspects of distributive justice for producers; use of a precautionary
approach in the management of environmental risk and food safety; and impacts on the welfare and intrinsic value of the fish.
There is a need to conduct a comparative analysis of the full economic cycle of the use of GM fish in aquaculture production
for developing countries. There is also a need to initiate an informed dialogue between stakeholders and strenuous efforts
should be made to ensure the participation of producers and their representatives from developing nations. An additional concern
is that any national licensing of the first generation of GM fish, i.e., in the USA, may initiate and frame an assessment
cycle, mediated by the WTO, which could dominate the conditions under which the technology will be applied and regulated globally.
Therefore, an integrated analysis of the technology development trajectories, in terms of international policy, IPR, and operational
implications, as well as an analysis of a broader range of ethical concerns, is needed. 相似文献
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Tatiana Wuytack Kris Verheyen Karen Wuyts Fatemeh Kardel Sandy Adriaenssens Roeland Samson 《Environmental monitoring and assessment》2010,171(1-4):197-204
In this study, we assess the potential of white willow (Salix alba L.) as bioindicator for monitoring of air quality. Therefore, shoot biomass, specific leaf area, stomatal density, stomatal pore surface, and stomatal resistance were assessed from leaves of stem cuttings. The stem cuttings were introduced in two regions in Belgium with a relatively high and a relatively low level of air pollution, i.e., Antwerp city and Zoersel, respectively. In each of these regions, nine sampling points were selected. At each sampling point, three stem cuttings of white willow were planted in potting soil. Shoot biomass and specific leaf area were not significantly different between Antwerp city and Zoersel. Microclimatic differences between the sampling points may have been more important to plant growth than differences in air quality. However, stomatal pore surface and stomatal resistance of white willow were significantly different between Zoersel and Antwerp city. Stomatal pore surface was 20% lower in Antwerp city due to a significant reduction in both stomatal length (?11%) and stomatal width (?14%). Stomatal resistance at the adaxial leaf surface was 17% higher in Antwerp city because of the reduction in stomatal pore surface. Based on these results, we conclude that stomatal characteristics of white willow are potentially useful indicators for air quality. 相似文献