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451.
Most research on animal contests has focused on the factors that influence the intensity and outcome of aggressive contests
within nonsocial species, while relatively little is known about contests in social taxa. Here, we examine contests among
queens of the social paper wasp, Polistes dominulus. Queens use multiple reproductive strategies, including nesting alone, usurping established colonies, and cooperatively joining
other queens. We stage contests between a nesting queen and a challenger to test how resource value (RV) and resource holding
potential (RHP) influence (a) who occupies the nest at the end of the contest and (b) the extent of conflict between the queen
and challenger. We found that RHP, as measured by individuals’ facial patterns and body size, influenced the outcome of the
contest. Challengers with high RHP were more likely to successfully usurp the nest than challengers with low RHP. Interestingly,
queens with relatively high RHP were more likely to form a cooperative association with the challenger than queens with lower
RHP, suggesting that queens may evict individuals that are an aggressive threat. RV influenced the intensity of conflict.
There was more aggressive conflict over large nests than over small nests. Overall, social taxa have complex contest dynamics
with important parallels to contests in nonsocial taxa. Studying contests in social taxa provides an important perspective
on the factors that influence individual decisions about conflict versus cooperation. 相似文献
452.
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454.
分析了太子河流域大型底栖动物群落结构,采用大型底栖动物Chandler生物指数、Shannon-Wienner多样性指数、BMWP-ASPT记分系统、BI指数,对2015年度平水期太子河流域进行了水质生物评价,对以上4个指数的结果进行了Pearson相关性分析,讨论了各生物指数的适用性。将BI指数的评价结果与理化结果进行了比较分析。结果表明:BI指数更适于太子河流域开展水质生物评价。 相似文献
455.
456.
文章基于"以人为本"的理念,构建了从使用者角度对城市绿地质量评价的简明指标体系,采用多边形综合指标法及德尔菲法,兼顾科学性和可操作性,并应用该指标体系尝试分析南京市城市绿地质量。结果表明:南京城市绿地总体质量处于一般水平,其中公园绿地和风景名胜与自然保护区绿地质量较高。在各项评价指标中,南京居民对绿地管理质量满意度较低,视觉效果满意度、空间布局满意度较高。该评价体系从使用者角度展现了城市绿地的整体水平并直观反映出城市绿地所存在的问题,可为城市绿地规划与管理以及综合评价指标的构建提供重要的依据与参考。 相似文献
457.
Sopan T. Ingle Nilesh K. Mahale Yogesh J. Mahajan Sanjaykumar N. Patil 《Local Environment》2015,20(11):1340-1362
The continuous infrastructural and economic development exerted pressure on the environmental conditions of the North Maharashtra region. The air quality of North Maharashtra region was analysed for the identification of hot spots and safe zones of ambient air quality. The result shows air pollution at some part of North Maharashtra region. The levels of particulate matter were above the prescribed limits especially at Bhusawal, Dhule and Jalgaon Urban centres. The traces of polyaromatic hydrocarbons were also observed in the urban centres of study area. The binary ratios of the persistent prevailing polycyclic aromatic hydrocarbon (PAH)'s show great correlation with the vehicular exhaust in the study region. The higher levels of pollutants in the study region were recorded in the post-monsoon season. The present study is first of its kind in the North Maharashtra region and an attempt has been made to analyse the anthropogenic sources and concentration of air pollutants in the area. The air pollutants reduce the defence system of human body and lead into severe health consequences like damage of lung tissues with escalation in the existing respiratory and cardiovascular diseases. 相似文献
458.
Environmental quality strongly depends on human behaviour patterns. We review the contribution and the potential of environmental psychology for understanding and promoting pro-environmental behaviour. A general framework is proposed, comprising: (1) identification of the behaviour to be changed, (2) examination of the main factors underlying this behaviour, (3) design and application of interventions to change behaviour to reduce environmental impact, and (4) evaluation of the effects of interventions. We discuss how environmental psychologists empirically studied these four topics, identify apparent shortcomings so far, and indicate major issues for future research. 相似文献
459.
A. O. Olowoporoku E. T. Hayes N. S. Leksmono G. P. Parkhurst 《Journal of Environmental Planning and Management》2010,53(3):385-403
The second round of the Local Transport Plan (LTP2) process in England presents unique challenges and opportunities for integrating Local Air Quality Management (LAQM) within current transport planning policy. Using content analysis of LTP2 documents from nine English authorities, and results from a questionnaire survey of local government officers undertaken in late 2007, this paper charts the changes in the integration of air quality management within the transport planning process since 1997. While substantial improvements in policy integration were observed within the selected case studies, the paper demonstrates that such improvements are often constrained by institutional complexities that create implementation gaps between national objectives and local decision-making outcomes. 相似文献
460.
水质自动监测系统运行过程中的质量保证和质量控制 总被引:9,自引:1,他引:8
孙南 《环境监测管理与技术》2009,21(1):62-64
以常州市武进水质自动监测站的工作为例,根据水质自动监测系统的技术特点,提出健全各项规章制度,培训技术人员,建立质量保证体系和自动监测系统运行的质量控制方法,以保证水质自动监测系统的正常运行。 相似文献