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511.
512.
Scientists assert that integrated research is a foundation of Sustainable Development. However, they often presume that differences between the bio-physical and social sciences are hurdles in the way of integration. We show that need not be the case. The problem lies in the way environmental research is organised. The essay goes on to discuss how the problem is being resolved, and the implications for ‘environmental science’. 相似文献
513.
HSE项目管理体系中环境保护专业的作用 总被引:1,自引:0,他引:1
饶未欣 《石油化工环境保护》2003,26(3):1-5
在对比国内建设项目环保管理体系和HSE环保管理体系的基础上,总结了PMC项目环保管理工作的经验,对HSE项目管理运作模式中环保专业的职能和作用进行了一定程度的探讨。 相似文献
514.
城市污水净化的环境效益与环境影响分析 总被引:1,自引:0,他引:1
对佛山城市污水净化系统的环境响应和效益预测原则,城市污水净系统正式运转将对佛山水道化纤厂至人民桥段及佛山涌水质有明显改善,其社会效益十分显著,但净化系统的建设交将带来以恶臭、卫生防疫和噪声等方面为主的不利环境影响。因此在城市环境建设中应尽量减少城市污水净化的负面影响,充分发挥其环境效应和社会效益,为城市环境综合整治创造良好的条件。 相似文献
515.
职业安全健康管理体系对企业经济和社会效益影响研究 总被引:1,自引:4,他引:1
为了评估职业安全健康管理体系的建立与企业经济和社会效益的关系 ,笔者对 12 5家企业的安全生产投入 ,因事故、职业病或违约造成的经济投入 (损失 ) ,以及建立职业安全健康管理体系后对企业经营活动及社会形象的影响进行了分析。结果发现 ,企业在建立职业安全健康管理体系期间及之后其安全生产投入比未建企业和建立体系之前增加 ;对事故、职业病或违约造成的经济投入加大 ;签订合同额和投标活动的中标率上升 ,员工抱怨次数及相关方抱怨次数下降。上述结果表明 ,职业安全健康管理体系的建立和运行对企业有良好的经济和社会效益。 相似文献
516.
Planqué R Dechaume-Moncharmont FX Franks NR Kovacs T Marshall JA 《Die Naturwissenschaften》2007,94(11):911-918
To perform tasks, organisms often use multiple procedures. Explaining the breadth of such behavioural repertoires is not always straightforward. During house hunting, colonies of Temnothorax albipennis ants use a range of behaviours to organise their emigrations. In particular, the ants use tandem running to recruit naïve ants to potential nest sites. Initially, they use forward tandem runs (FTRs) in which one leader takes a single follower along the route from the old nest to the new one. Later, they use reverse tandem runs (RTRs) in the opposite direction. Tandem runs are used to teach active ants the route between the nests, so that they can be involved quickly in nest evaluation and subsequent recruitment. When a quorum of decision-makers at the new nest is reached, they switch to carrying nestmates. This is three times faster than tandem running. As a rule, having more FTRs early should thus mean faster emigrations, thereby reducing the colony’s vulnerability. So why do ants use RTRs, which are both slow and late? It would seem quicker and simpler for the ants to use more FTRs (and higher quorums) to have enough knowledgeable ants to do all the carrying. In this study, we present the first testable theoretical explanation for the role of RTRs. We set out to find the theoretically fastest emigration strategy for a set of emigration conditions. We conclude that RTRs can have a positive effect on emigration speed if FTRs are limited. In these cases, low quorums together with lots of reverse tandem running give the fastest emigration. 相似文献
517.
John P. Kent Kenneth J. Murphy Finian J. Bannon Niamh M. Hynes Thomas J. Hayden 《Die Naturwissenschaften》2009,96(7):763-770
Testosterone (T) concentrations in many species are sensitive to seasonal changes and to changes in social conditions. However,
the effect of the natural or endogenous T increase in the juvenile on their social behaviour is not well understood. In this
study, T and behaviour were measured from the pro-social juvenile to the adult stage in semi-feral domestic fowl. During the
pro-social phase T levels and the distance chicks maintained between each other, i.e. inter-individual distance (IID) were
low. Then, as T increased, a corresponding increase in IID occurred and continued in males until dispersal to individual adult
male territories. In the new and initially stable adult social structure, T declined and IID remained high, indicating a new
behavioural mechanism was in place. Males first mated as T levels were declining. They were then challenged; then T increased,
and then IID increased again. Adult male T levels fluctuate, being low or declining in a socially stable environment and increasing
following a challenge, suggesting a regulatory or modulating role for T. The results are consistent with T having an endogenous
role: in the juvenile, driving behavioural change towards adulthood, and in adulthood, a modulating role regulating social
organisation. 相似文献
518.
519.
Patrick Gautier Marco Barroca Sophie Bertrand Cyril Eraud Maria Gaillard Michael Hamman Sébastien Motreuil Gabriele Sorci Bruno Faivre 《Behavioral ecology and sociobiology》2008,62(7):1159-1166
Several environmental factors have been shown to shape the pattern of investment of carotenoids into the expression of sexual
signals. Surprisingly, the impact of the social environment has been neglected. If a carotenoid-based sexual trait is used
by females to choose a mate or by males to assess the quality of potential competitors for mates, males, in the presence of
females, should upregulate expression of the trait. We tested this hypothesis in male zebra finches that were housed either
with females or in a male-only social environment. Additionally, to investigate whether the social modulation of the expression
of a sexual trait depends on the physiological need of carotenoids, we challenged half of the males with Escherichia coli lipopolysaccharide (LPS). We found that the social environment modulated the expression of bill color, with males kept in
the presence of females harboring a redder bill at the end of the 3 weeks that the experiment lasted. Males injected with
LPS showed duller bill color regardless of the presence of females, and social interactions with females result in upregulated
bill color similarly for phosphate-buffered saline (PBS) and LPS males. Thus, social environment and immune activation had
an additive effect on the expression of bill color. The effect of social environment on plasma carotenoids was less clear.
Indeed, a first replicate of the entire experiment showed that both immune challenge and social context affected bill color,
with a negative effect of immune challenge and a positive effect of the presence of females on circulating carotenoids. However,
a second replicate of the experiment showed only a negative effect of the immune challenge. These results, therefore, suggest
that the social environment can affect the expression of carotenoid-based sexual traits under both benign and carotenoid-demanding
conditions. Whatever the signaling function of bill color (female mate choice or male–male competition for mates), the observed
flexibility may be adaptive because the expression of the signal can be modulated depending on the expected rewards or costs
associated with the presence or absence of females. Nevertheless, the mechanisms underlying such an effect are still unknown. 相似文献
520.
Yutaka Saito Anthony R. Chittenden Kotaro Mori Katsura Ito Atsushi Yamauchi 《Behavioral ecology and sociobiology》2008,63(1):33-42
The number of nests containing egg masses a female makes over her lifetime and the pattern of scattering nests vary among
species in a genus of nest-weaving spider mites (Stigmaeopsis). We hypothesized that the scattered nests of small nest builders have a previously overlooked indirect effect in that the
void nests created after predation take on a new role as hindering devices that effectively decrease predator searching efficiency.
First, we demonstrated that the experimental design used in this study is a good reflection of the nest distribution pattern
of Stigmaeopsis takahashii (an intermediate-sized nest builder) in the field. Using this species as a model, we tested how different nest-scattering
patterns affect the predator to examine how scattering may indirectly provide an anti-predation strategy by increasing a predators
searching time. Next, we observed how artificially arranged void nests disturb predatory behavior in both starved and fully
fed predator females and showed that void nests have a strong hindering effect on predators. Thus, we concluded that the nesting
behavior of this mite species not only has anti-predator effects but must also have a stabilizing effect on predator–prey
interaction systems at the population level. 相似文献