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201.
江苏省水污染物排放及治理水平分析   总被引:2,自引:0,他引:2  
姜伟 《环境科技》2002,15(3):36-37
在对大量环境统计数据汇总分析的基础上,系统阐述江苏省社会经济发展和水污染物排放情况,并就目前江苏省水污染物治理水平与国内其他地区进行了对比分析。  相似文献   
202.
从技术性能上介绍石油化工工艺管道电伴热的优势和目前蒸汽伴热的缺陷。并以我公司一套常减压装置渣油线伴熟为例,对两种伴热方式进行比较和经济分析。  相似文献   
203.
论上海环境与社会经济的协调发展   总被引:2,自引:0,他引:2  
从环境是资源这一观点出发,论述了环境与社会经济协调发展的必要性。在此基础上,分析了上海10年多来坚持协调发展原则,环境质量恶化趋势得到控制,局部质量有所好转的现状:指出了实现2010年上海环发目标,主要对策措施:建立综合决策机制;纳入国民经济与社会发展计划:较大幅度增加环保投入,加强立法、强调法制和依靠科技进步。  相似文献   
204.
In a long-term field manipulation, we demonstrate strong reactions of Leptothorax longispinosus ant colonies to food- and nest-site supplementation. Demographic and genetic responses varied over small geographic scales, and the two ecological factors interacted with the presence of the social parasite Protomognathus americanus. We conducted a 2×2 experiment in three blocks and found that the blocks, which were less than 100 m apart, reacted very differently to the treatments. Blocks differed in degree of polygyny, intranest relatedness, colony size, productivity, and sexual investment. Furthermore, these differences were associated with the presence of slave-making ants and the local availability of nest sites. Nest-site supplementation had a strong effect only in the site with the highest prevalence of social parasites, influencing there the density and investment patterns of colonies. L. longispinosus ants in the least parasitized area were strongly affected by both food- and nest-site supplementation. There, food supplementation led to a decrease in the number of queens per colony and consequently to an increase in intranest relatedness, while colonies in nest-site-supplemented areas invested fewer resources in males and produced a female-biased allocation ratio. By contrast, in a third block with a very low intracolonial relatedness, food supplementation induced an absolute and relative higher investment in males. We conclude that ecological factors influencing social organization in insect societies cannot be studied in isolation, because the interactions among factors produce far richer responses than any one variable.Communicated by L. Sundström  相似文献   
205.
A growing body of evidence suggests that social bonds have adaptive value for animals that live in social groups. Although these findings suggest that natural selection may favor the ability to cultivate and sustain social bonds, we know very little about the factors that influence the quality or stability of social bonds. Here, we draw on data derived from a 16-year study of baboons living in seven different social groups in the Amboseli basin of Kenya to evaluate the quality and stability of social bonds among females. Our results extend previous analyses, which demonstrate that females form the strongest bonds with close maternal and paternal kin, age mates (who may be paternal kin), and females who occupy similar ranks but are not maternal relatives. Here we show that the same factors influence the quality and strength of social bonds. Moreover, the results demonstrate that the quality of social bonds directly affects their stability.  相似文献   
206.
We analysed 16 years of census data gathered on the island of Hirta (archipelago of St. Kilda) to investigate the effects of castration, population density, sex ratio, season and group type on habitat use and social segregation of Soay sheep. From 1978 to 1980, 72 male lambs were castrated. We used this experiment to study how a change in reproductive status could affect sociality and habitat choice of these males. Males, females and castrates were all segregated outside the rutting season in autumn. Castrates were the least segregated from females in spring and summer but were most segregated from them during the pre-rut. The more equal the sex ratios, the higher was the degree of social segregation. The three sex classes used similar habitat types, namely, Holcus agrostis, Agrostis festuca and Calluna habitats. Holcus agrostis and Agrostis festuca were top- and second-ranked in female and castrate habitat use, while Holcus agrostis and Calluna were the two top habitat types used by rams. It is unclear why males included Calluna heath habitats, but it cannot be excluded that they might have shifted their use depending on forage availability. A lack in differences in habitat use between castrates and females suggests that body size differences alone cannot be the driving factor for habitat segregation in male and female Soay sheep and that there are reasons other than body size that could motivate reproductive males to use additional habitat types, such as Calluna heath. Although habitat use shifted from one habitat type to the next between low- and high-population-density years and between seasons, there was no clear link between population density and how different groups (male, female or castrate) used these areas. We discuss effects of reproductive status, population density and sex ratio on social segregation and habitat use and suggest that these factors need to be taken into account when investigating causes of sexual segregation in ungulates.  相似文献   
207.
A number of socioecological models assume that within-group food competition is either weak or absent among folivorous primates. This assumption is made because their food resources are presumed to be superabundant and evenly dispersed. However, recent evidence increasingly suggests that folivore group size is food-limited, that the primates prefer patchily distributed high-quality foods, and display some of the expected responses to within-group scramble competition. To investigate this apparent contradiction between theoretical models and recent empirical data, we examined the foraging behaviour of red colobus monkeys (Piliocolobus tephrosceles) in Kibale National Park, Uganda. We found that red colobus monkeys foraged in a manner that suggests they deplete patches of preferred foods: intake rate slowed significantly during patch occupancy while movement rate, an index of foraging effort, increased. Furthermore, patch occupancy was related to the size of the feeding group and the size of the patch. These results suggest that within-group scramble competition occurs, may limit folivore group size, and should be considered in models of folivore behavioural ecology.  相似文献   
208.
We studied the effect of prior experience to eggs laid by nestmate and non-nestmate queens on the acceptance of queen-laid eggs by worker wood ants, Formica fusca. We transferred eggs from a non-nestmate queen into colonies during early spring, when their own queen was recommencing egg laying. A few weeks later, workers from these “experienced” colonies accepted eggs of both familiar (44% acceptance) and unfamiliar (40%) non-nestmate queens much more than workers from control colonies (2%) that had only had previous contact with their own queen’s eggs. Thus, prior exposure to eggs laid by a non-nestmate queen induces much greater acceptance of all non-nestmate queen-laid eggs. Mechanistically, we hypothesize that exposure to eggs from several queens may increase acceptance by causing a highly permissive acceptance threshold of non-nestmate queen-laid eggs rather than by widening the template for acceptable queen-laid eggs. These novel results show that egg-discrimination behaviour in F. fusca is flexible and that workers respond to the diversity of eggs experienced in their colony.  相似文献   
209.
Introduction: There has been a significant increase in online purchasing and product safety problems have been identified in e-commerce. This study examines consumer behavior and safety perceptions among parents purchasing child products online. Method: A mixed methods approach, including focus groups and a survey with parents, identified key characteristics and behaviors. Cluster analysis was used to determine different population segments (including “Informed,” “Uninformed,” and “Infrequent” consumer groups) based on their frequency of online shopping and search for product information. “Safe” and “Unsafe” behavior groups were identified related to their search for safety information on child products. Logistic regression analysis was used to study the effects of consumer type groups and demographic variables on the chances of being a safer consumer. Results: Findings indicate that child product safety considerations are not a priority for parents when shopping online. Only 62% of the survey respondents indicated that they search for information prior to buying a child product online, of which only 13% of the respondents noted that they search for information on product safety. Risky consumer behaviors were identified including the purchase of imitation products (counterfeit or knockoff products) and autonomous checks for product safety in lieu of safety standards. The logistic regression analysis found that being an “Uninformed Consumer” increases the odds of an individual being an “Unsafe Consumer” by 8.4 times (χ2(11) = 97.33, p < .001). Practical Applications: Design of a social marketing campaign that targets these different population segments to change perceptions and promote safe online purchasing is recommended.  相似文献   
210.
Working toward sustainable community is a complex task for communities especially given the ambiguous nature of implementing the concept of sustainable development. However, by working to understand the nature of community capital, administrators can begin to move beyond bottom line thinking toward a more comprehensive and collective view of community. This paper presents a theoretical framework that helps municipal decision makers begin collecting information they need to help them build sustainable and resilient communities.
Edith G. CallaghanEmail:
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