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101.
Song as an attractant for male and female European starlings,and the influence of song complexity on their response 总被引:2,自引:0,他引:2
Summary We tested the hypothesis that song attracts females and repels males in the European starling. We broadcast recorded song from speakers attached to nestboxes, while paired boxes with silent speakers served as controls. As predicted, females were attracted to the song boxes. Contrary to prediction, males were also attracted to the `song' boxes. Singing by male starlings may be costly because it attracts competitors for limited nesting sites, but the cost cannot be avoided due to the need to attract a mate. In a second experiment simple song (composed of 20 different phrase types) and complex song (40 phrase types) were played simultaneously. More males were captured at boxes where simple song was played. Song complexity may function as an indicator of male quality and be used by male starlings to assess potential competitors. 相似文献
102.
David R. McCallum 《Environmental monitoring and assessment》1987,8(3):199-215
The environmental impact assessment procedure for Canadian federal government projects is briefly described. In the non-legislated Canadian system, follow-up to assessments is one of the major means of encouraging and improving the implementation of environmental impact assessment and the quality of environmental work done around development projects. The results of a study on the status of follow-up in the Canadian Government are presented. Factors that limit and that are conducive to follow-up are discussed. The effectiveness of follow-up depends as much on the circumstances surrounding a project and the concerned parties as on the follow-up techniques used; both of these aspects can be addressed in the planning and management of follow-up and of environmental impact assessment overall. Areas for improving the management of follow-up are identified and discussed: planning of follow-up activities, coordination of concerned parties, generation of clear understandings, information management, resource allocation, and maintenance of credibility. A method for planning follow-up activities for specific projects is presented. 相似文献
103.
104.
T. E. Lewis A. B. Crockett R. L. Siegrist 《Environmental monitoring and assessment》1994,30(3):213-246
Concerns over data quality have raised many questions related to sampling soils for volatile organic compounds (VOCs). This paper was prepared in response to some of these questions and concerns expressed by Remedial Project Managers (RPMs) and On-Scene Coordinators (OSCs). The following questions are frequently asked:
- Is there a specific device suggested for sampling soils for VOCs?
- Are there significant losses of VOCs when transferring a soil sample from a sampling device (e.g., split spoon) into the sample container?
- What is the best method for getting the sample from the split spoon (or other device) into the sample container?
- Are there smaller devices such as subcore samplers available for collecting aliquots from the larger core and efficiently transferring the sample into the sample container?
- Are certain containers better than others for shipping and storing soil samples for VOC analysis?
- Are there any reliable preservation procedures for reducing VOC losses from soil samples and for extending holding times?
- Open test pit or trench.
- Surface soils (<5 ft in depth).
- Subsurface soils (>5 ft in depth).
105.
W. Henry McNab 《Environmental monitoring and assessment》1996,39(1-3):215-229
Five local ecological types based on vegetative communities and two landscape types based on groups of communities, were identified by integrating landform, soil, and vegetation components using multivariate techniques. Elevation and several topographic and soil variables were highly correlated with types of both scales. Landscape ecological types based only on landform and soil variables without vegetation did not correspond with types developed using vegetation. Models developed from these relationships could allow classification and mapping of extensive areas using geographic information systems. 相似文献
106.
Lawrence C. C. Koe 《Environmental monitoring and assessment》1988,10(1):75-84
Odorous gases emitted from refuse wastes were scrubbed through activated carbon columns until odor breakthrough occured. Refuse air samples were collected at the influent and effluent ports of the columns for analysis on a gas chromatograph-mass spectrometric system and for odor determination by dynamic olfactometry. Chromatographic profiles of the gases emitted from refuse material were obtained and volatiles identified included carboxylic acids and some sulphur compounds. Organoleptic tests with a dynamic olfactometer revealed that the odor concentration of refuse air averaged about 50 sou m–3. The adsorption capacities of four commercial grades of activated carbon for refuse odor were evaluated and compared. Results indicated that chemically impregnated activated carbons that are commonly used for odor control at sewerage facilities were less cost effective than non-chemically impregnated carbons. 相似文献
107.
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109.
Summary As stated at the beginning of this paper conclusions reached thus far cannot be discussed in this paper. However, a great deal of information is available for examination.EPA displayed its ability to coordinate widely separated laboratories, both Federal and private, into a smooth working team in a very short period of time. A very comprehensive study plan was also developed and implemented quickly. EPA was fortunate to have already had GCA under contract when the emergency arose. In no small part the success of the field effort was due to the managerial and technical abilities of the GCA team.Within a period of 6 weeks a plan was developed, a prime contractor retained, subcontractors hired, and field activities begun. Within a period of 3 months in excess of 8600 field samples were collected and over 12,000 field and QC samples were analyzed. During this same period 2 major data systems were developed, debugged, and placed into operation.In short this EPA project was probably the most comprehensive multimedia field project ever attempted by EPA and certainly the data is being subjected to the most strenuous quality control measures ever imposed by this Agency. The entire program is presently under peer review and the results are being prepared for publication by EPA Headquarters.Note. Originally intended to be published as part of the special issue on Exposure Monitoring: An International Workshop (Las Vegas, Nevada, October 19–22, 1981). 相似文献
110.