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21.
浅谈环境监测社会化的质量监管新思路   总被引:1,自引:0,他引:1  
分析了现阶段社会环境检测市场的发展现状及存在的问题,探讨了从环境检测上岗能力、专业技能再教育、从业履历和信用等方面对社会环境检测从业人员进行管理的必要性,提出在机构环境监测能力、检测人员结构流动性、仪器设备在用状态和更新频率、从事环境监测业务信用等方面建立评估机制,推动环境监测市场健康发展。  相似文献   
22.
Do natural resources reduce social trust? This paper reviews the literature on natural resources and on trust. The existing theoretical and empirical literature suggests that natural resources can reduce trust through several indirect mechanisms. Notably, studies show that natural resources lead to institutional degradation, corruption, inequality, and civil war, all of which have been associated with reduced trust. In addition, game theoretical work on windfall gains suggests that there may be direct effect of natural resources on trust. This paper tests empirically whether there is a direct effect of natural resources on trust (The Pearl Hypothesis), using cross-country data. The results indicate that no such direct effect exists, but we find a significant effect on trust of intermediate variables affected by natural resources, such as institutions, corruption, inequality and/or civil war. Importantly, the relationship between corruption and trust turns out to be non-linear, indicating that the effect of natural resources on trust depends on the initial corruption level of a country. In highly corrupt societies, institutional improvements that reduce corruption may also undermine trust, which poses difficult challenges for anti-corruption policy.  相似文献   
23.
We exploit recent advances in climate science to develop a physically consistent, yet surprisingly simple, model of climate policy. It seems that key economic models have greatly overestimated the delay between carbon emissions and warming, and ignored the saturation of carbon sinks that takes place when the atmospheric concentration of carbon dioxide rises. This has important implications for climate policy. If carbon emissions are abated, damages are avoided almost immediately. Therefore it is optimal to reduce emissions significantly in the near term and bring about a slow transition to optimal peak warming, even if optimal steady-state/peak warming is high. The optimal carbon price should start relatively high and grow relatively fast.  相似文献   
24.
Determining the evolutionary basis of variation in reproductive skew (degree of sharing of reproduction among coexisting individuals) is an important task both because skew varies widely across social taxa and because testing models of skew evolution permits tests of kin selection theory. Using parentage analyses based on microsatellite markers, we measured skew among female eggs (n=32.3 eggs per colony, range=20–68) in 17 polygynous colonies from a UK field population of the ant Leptothorax acervorum. We used skew among eggs as our principal measure of skew because of the high degree of queen turnover in the study population. Queens within colonies did not make significantly unequal contributions to queen and worker adult or pupal offspring, indicating that skew among female eggs reflected skew among daughter queens. On average, both skew among female eggs (measured by the B index) and queen–queen relatedness proved to be low (means±SE=0.06±0.02 and 0.28±0.08, respectively). However, contrary to current skew models, there was no significant association of skew with either relatedness or worker number (used as a measure of productivity). In L. acervorum, predictions of the concession model of skew may hold between but not within populations because queens are unable to assess their relatedness to other queens within colonies. Additional phenomena that may help maintain low skew in the study population include indiscriminate infanticide in the form of egg cannibalism and split sex ratios that penalize reproductive monopoly by single queens within polygynous colonies.  相似文献   
25.
The benefit of group living is a fundamental question in social evolution. For sociality to evolve, each individual must gain in terms of some fitness component by living in larger groups. However, in social insects, a decrease in per capita success in brood production has been observed in larger groups. While it has been proposed that this decrease could be outweighed by an increase in the predictability of success, a functional basis to this hypothesis has so far never been demonstrated. In this paper, using foraging economics as a functional proxy to colony productivity, we construct a model to explore how number of foragers in the colony interacts with the ecology of resources to influence per capita foraging success and its predictability. The results of the model show that there is no increase in per capita foraging success in larger colonies under most circumstances, though there is an increase in its predictability. We then test the model with empirical data on the foraging behavior of the primitively eusocial wasp, Ropalidia marginata. The consistency between the data and the model suggests that foraging economics could provide a robust functional basis in explaining the relationship between colony size and productivity.  相似文献   
26.
Gregarious behaviour (i.e. living in groups in contrast to a solitary life) is commonly observed in mammals, but rarely documented in amphibians. Environmental features and/or animal mutual attractions can promote the formation of aggregations that may both reduce the risks of dehydration and predation and increase mate access and fitness. Luschan’s salamander (Mertensiella luschani) lives in permanently arid Mediterranean environments; individuals shelter in cracks and crevices and leave only during favourable periods. In this study we examined the role of chemical tracks, in self and conspecific recognition (i.e. gregarious/solitary behaviour), on the social structure of this species. Our results show that juveniles and adults of both sexes use chemical scents deposited on substrate to relocate their shelter. In contrast to numerous other salamander species, Luschan’s salamanders also use social information, conveyed by conspecific scents, to identify a safe shelter. Furthermore, this scent marking does not play a role in sexual attraction but allows sex discrimination. This species exhibits gregarious behaviour (i.e. conspecific attraction) as a possible adaptation to dry environments. We discuss both ultimate and proximate factors in the evolution from a solitary to a gregarious life.  相似文献   
27.
The effects of immigration on the behaviour of residents may have important implications for the local population characteristics. A manipulative laboratory experiment with yearlings of the common lizard (Lacerta vivipara) was performed to test whether the introduction of dispersing or philopatric individuals influences the short-term spacing behaviour of resident individuals. Staged encounters were carried out to induce interactions within dyads. The home cage of each responding individual was connected by a corridor to an unfamiliar “arrival cage” to measure the latency to leave their own home cage after each encounter. Our results showed that the time that pairs spent in close proximity was longer when a dispersing individual was introduced in the home cage. The latency to leave the home cage was longer after the introduction of a dispersing individual. These response variables were not influenced by the relative body sizes of contestants nor by the level of aggression towards each other. In contrast, the aggressive response was significantly influenced by the residency asymmetry established experimentally (“owner” of the home cage vs introduced individual). Our results suggest that the space use by resident individuals is influenced by the dispersal status of conspecifics. The potential ultimate causes driving this effect are discussed.  相似文献   
28.
Many studies assume that selection molds social traits and have investigated the manner in which this occurs, yet very few studies have measured the strength of selection on social traits in natural populations. In this paper, I report results of phenotypic selection analyses on two social traits – the size of social groups and the frequency of group foraging – in Phyllostomus hastatus, the greater spear-nosed bat. I found significant positive directional selection on individual group foraging frequency, but no directional selection on individuals in different-sized social groups. These results have implications for the structure of social groups, cooperative behavior among group mates, and maternal investment strategies. I argue that combining studies of natural selection on wild populations with experiments to identify the agents and mechanisms of selection can do much to increase our understanding of social evolution.  相似文献   
29.
The utilisation of Social Impact Assessment (SIA) in Iran is analysed in terms of its policy context and its application in practice. Five case studies where SIA was employed in conjunction with Environmental Impact Assessments (EIA) for agricultural development projects are evaluated. In addition, the performance of the policy context is assessed. This research revealed that there are legal and institutional constraints to the effective functioning of SIA in Iran, and that there are deficiencies in the operating guidelines. There were serious problems associated with the way SIA was undertaken in all five case studies. Recommendations to improve the policy framework for the conduct of SIA are made. The recommendations advocate for a higher profile of SIA within legislation, for social issues to have greater emphasis in official guidelines for the conduct of EIA and SIA, and for a range of measures to increase the professionalism of SIA practice.  相似文献   
30.
结合工作实际对如何有效利用监测数据进行了探讨 ,并引申出监测数据的 4种效应 ,即信息效应、价值效应、广告效应和政治效应。  相似文献   
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