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31.
《Journal of Natural History》2012,46(4):649-660
Density-related changes in performance have been documented for a number of different ungulate species, with recorded decline in body weight, fecundity and both juvenile and adult survival as population densities increase. While density-dependent responses of this kind have been explored in some detail in red, roe and fallow deer, little published information is available on demographic responses to density in European populations of sika deer (Cervus nippon). This paper offers an analysis of the dynamics of two populations of sika from the south of England from 1985–1993. Data on age-related body weights for males and females and pregnancy rates of females are taken from analysis of cull records of 321 males and 534 females culled during that 8-year period. We describe trends in body mass of adult and juvenile sika of both sexes, and consider changes in pregnancy rates of both mature and yearling females in relation to changes in relative abundance. Despite steadily increasing population density between 1985 and 1991/1992, no consistent decline was recorded in body weight or condition (as measured by % cover of kidney fat) for calves or yearlings of either sex, or for mature females. A decline in recorded body weight of adult males was not significantly correlated to ranked relative abundance. Fecundity was high (with > 90% of mature females sampled found pregnant). Most mature females found pregnant were also lactating. The proportion of animals that conceived as yearlings (72%) was lower than that recorded for more mature hinds; however there is some indication that the difference recorded may simply reflect the fact that yearlings may conceive later in the season than older animals. No significant differences were apparent in the proportion of either adult or yearling females found pregnant in different years. 相似文献
32.
金融教育的国际经验与借鉴 总被引:1,自引:0,他引:1
金融的深化发展要求居民的金融素质相应地提高。然而,不论是发达国家还是发展中国家,国民的金融素质状况都不容乐观,加强金融教育成为提高国民金融素质的重要措施。美国、印度、英国在加强金融教育方面的做法值得我们借鉴。目前我国居民在使用金融产品时仍存在许多问题,因此应采取措施多方位提高我国国民的金融素质。 相似文献
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刘苏荣 《曲靖师范学院学报》2010,29(2):59-63
二战后,英国迅速建立起了国家基本养老金,随后在1959年又建立了国家补充养老金。20世纪70年代以来,英国政府积极进行福利制度改革,职业养老金和私人养老金得到了大力提倡。英国对养老金制度进行变革的目的在于逐步实现养老金制度的社会化和市场化,并最终实现政府在英国养老金制度中角色的转变。 相似文献