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ROUABHI Rachid DJEBAR-BERREBBAH H DJEBAR MR 《应用与环境生物学报》2006,12(4):514-517
Harmful bugs affect food production,directly by the qualitativeor quantitative reduction of the harvests,or indirectly while servinglike vectors of several illnesses of the plants and human[1].Many chemical products are used by human for a long time inthe… 相似文献
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Dr. William C. Metz 《Environmental geochemistry and health》1982,4(4):131-140
After a lapse of almost two decades, US energy and mining companies are once again involving themselves with worker housing. Reinvolvement began in the 1970s. It is in response to a recognition of the fiscal consequences of project delays and an industry responsibility to both workers and project area communities. It differs from the heavy reliance on company towns which were prevalent in the US during the 19th and early 20th Centuries. Industry involvement now relies not only on supply, but on stimulation. A greater variety of housing initiatives is being utilised and a company must carefully select the housing initiative best suited to its circumstances. These initiatives need to be guided by the following set of decision guidelines: (1) housing function; (2) housing user; (3) housing type and quantity needs; (4) monetary expectations; (5) role of the industry; (6) housing unit location; (7) responsibilities after housing is completed; and (8) amenities and community sharing. Then, housing involvement must be reviewed in light of past and present industry experiences. Innovative ideas need to be evaluated with respect to proven initiatives, as well as their presumed goal and potential for success.Study performed under Contract No. DE-AC02-76CH00016 with the U.S. Department of Energy 相似文献
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For a community to manage hazards successfully, those who are responsible for planning and implementing responses to a disaster threat situation must understand the social and economic realities of populations at risk. A random sample survey of residents in the vicinity of a US Army chemical weapons storage depot in Alabama confirms that those in the lowest quartile of household income (i.e., less than US $25,000 in 1999) differ in important ways from the rest of the sample. Using economic status as a grouping variable resultedin identifying a concentration of individuals with special needs. This group differed significantly from the remainder of the sample as to demographic and attitudinal characteristics, hazard knowledge and concerns, emergency preparedness, and emergency decision-making and their likelihood of taking protective actions. Respondents in the lowest income quartile reported greater restrictions in physical abilities, fewer community contacts, a heightened concern about area hazards, and limited resources for taking preparedness and response actions. 相似文献
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Markus Metz Georg M. Klump Thomas W. P. Friedl 《Behavioral ecology and sociobiology》2007,61(9):1369-1381
The red bishop (Euplectes orix) is a highly polygynous and colonial weaverbird. Males construct several nests within their territories to which they try
to attract females, and females are solely responsible for incubation and raising offspring. In this paper, we describe the
characteristics of the red bishop’s mating system as a biological market and investigate the role of nests built by males
as a traded commodity in a mating market. As timing of breeding in red bishops in arid and semi-arid zones depends on rainfall
patterns which are often unpredictable, there are temporal changes in demand for and supply of nests within a breeding season,
with breeding activities of males and females being highly synchronised. We found that males increased their nest-building
speed with increased female breeding activity independently of rainfall, indicating that supply follows demand in this mating
market. The supply of nests was always larger than the demand for nests. Construction costs for nests increased with demand
for nests as indicated by shorter nest-building duration and shorter building delays between two consecutively built nests
at times of high breeding activity. Males as a trading class are chosen according to the age of their nests offered, with
young nests having a higher probability of being accepted by females. Furthermore, female choosiness with regard to nest age
decreased when their own market value decreased, as predicted by biological market theory. The temporal changes of breeding
activity together with the female preference for young and fresh nests require that males quickly adjust nest-building activity
to varying female demand for new nests. However, males with a better adjustment of building speed to female breeding activity
did not gain higher mating success. 相似文献