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941.
Lars Guenther Peter Weingart Corlia Meyer 《Environmental Communication: A Journal of Nature and Culture》2018,12(8):1046-1061
ABSTRACTIn science communication, a prerequisite for reaching different parts of a society is to find out how these publics experience and interpret science. Since rural South African publics are perceived to exhibit a large cultural distance to science, the present exploratory study aimed to know in more detail how rural South Africans perceive and understand science in their local and social contexts. Theoretical notions on cultural distance and the methodological approach of segmentation studies were considered. Semi-structured interviews with rural South Africans were carried out in four towns (n?=?52) that differ with respect to having a large scientific installation in their vicinity, or not. Sensitively comparing local and social contexts helped identifying three different publics who differed regarding their perceptions of science; however, the large scientific installations only made a difference in perceptions for those publics who were generally less exposed to and less knowledgeable about science. 相似文献
942.
943.
成体神经发生是脊椎动物中广泛存在的一种生物学特征。成体硬骨鱼类的脑展现出强烈的神经活性以及出色的脑修复能力,这使得硬骨鱼类成为研究成体神经发生和脑修复的一个理想的模型。本文克隆了成体稀有鮈鲫(Gobiocypris rarus)脑组织中神经发生及脑修复相关的hes5、pax6、sox11和prox1基因的部分c DNA序列并进行了序列分析。序列分析结果表明,pax6和sox11基因片段与斑马鱼(Danio rerio)对应的基因片段的同源性最高,分别为97%和94%;hes5基因与鲤鱼(Cyprinus carpio)相对应的基因片段的同源性最高,为92%;prox1基因在物种间的同源性最低。基于稀有鮈鲫和已知物种相应基因的核苷酸序列构建了系统发育树,发现稀有鮈鲫prox1基因与其他硬骨鱼类的亲缘关系最远。本文为进一步开展神经毒性类化学品对水生生物鱼类的成体神经毒性作用机制研究提供了分子生物学基础。 相似文献
944.
为研究辽东湾表层沉积物中多环芳烃(PAHs)的来源特征,2014年5月采集了20个辽东湾海域表层沉积物样品,并利用气相色谱质谱联用仪对优先控制的16种PAHs进行测定,采用聚类分析、主成分分析-多元线性回归分析、异构体比值3种统计方法对辽东湾表层沉积物中PAHs来源特征进行了研究。结果表明,辽东湾表层沉积物中PAHs含量范围88.5~199.3 ng·g-1,平均值为(126.3±35.3)ng·g-1,其中,萘、菲和荧蒽是PAHs优势组分。通过统计分析结果表明,辽东湾北部表层沉积物中PAHs含量低于西南部,沉积物中PAHs的来源包括石油燃烧来源、煤炭、木材等生物质燃烧来源和石油来源,其中燃烧来源是主要来源,煤炭、木材等生物质燃烧来源占49.9%,石油燃烧来源和石油来源占50.1%。 相似文献
945.
Antonis Skouloudis Nikoleta Jones Spyridon Roumeliotis David Issac Alison Greig Konstantinos Evangelinos 《Journal of Environmental Planning and Management》2017,60(9):1575-1600
This paper explores the notion of environmentally induced spatial stigma through an analysis of data from interviews across public attitudes to pollution within the Asopos river basin in central Greece. The area has a 40 year plus history of legal and illicit industrial waste disposal and public debate on the associated environmental degradation. The study focuses on the perceptions and beliefs of a sector of the community likely to be directly and negatively affected by stigma, that is small business owners in the tourism and hospitality sector. The qualitative analysis explores awareness and viewpoints on environmental degradation and water quality within the local context, implications for the local economy and the individual's own enterprise, views on industrial environmental management as well as corporate responsibility and future prospects for the environmental problems of Asopos. Findings reveal a noticeable variation in views on industrial pollution and ecosystem deterioration among the respondents, but overall a strong environmentally induced stigmatization of the area. They also uncover an information asymmetry and lack of credible commitment by government bodies and industry members in disclosing accurate information, a situation likely to increase speculation and uncertainty within the community. The paper concludes by addressing implications of the findings to policy-making and managerial considerations, along with future research perspectives which aim to increase considerations of sustainability aspects for local development. 相似文献
946.
围垦后南汇东滩海三棱藨草的空间分布及其影响因子研究 总被引:3,自引:0,他引:3
2015年9月~10月期间对2012年底围垦后南汇嘴区域的海三棱藨草(Scirpus mariqueter)湿地系统进行了调研,运用主成分分析、典范对应分析(canonical correspondence analysis,CCA)方法,基于101个样地土壤的有机碳、总磷、总氮、硝酸盐氮、亚硝酸盐氮、氨氮、正磷酸盐、pH、含水率、粒径、盐度、滩涂高程等12个环境因子数据,探讨了围垦后海三棱藨草空间分布的关键影响因子。结果表明:海三棱藨草的分布与滩涂高程具有显著正相关(P0.05),海三棱藨草群落主要分布在南汇滩涂2.5~3.4 m高程范围内;海三棱藨草的密度、盖度与盐度呈显著正相关(P0.05)。结论认为滩涂高程和土壤盐度是影响海三棱藨草分布的主要环境因子。未来需要结合围垦后的水动力变化过程数值模拟,对海三棱藨草生态系统高时空分辨率的响应过程及机制进行研究,以进一步确立海三棱藨草对围垦工程响应的关键阈值。研究对围垦工程后的滨海湿地植被恢复及滩涂生态修复具有参考意义。 相似文献
947.
Rebecca Willis 《环境政策》2017,26(2):212-231
The politics of climate change is much discussed, but there has been little investigation into how politicians themselves understand or articulate the issue. Corpus analysis, a method developed within linguistics, is used to investigate how UK politicians talk about climate change, using the example of the 2008 Climate Change Bill. Corpus techniques, including keyword analysis, collocation and semantic tagging, are used, alongside critical reading of the text. The analysis shows that politicians frame climate change as an economic and technical issue, and neglect discussion of the human and social dimensions. They are selective in their use of scientific evidence, with little mention of abrupt or irreversible change. In doing so, they attempt to ‘tame’ climate change, rather than confronting difficult realities. While this strategy has the benefit of political acceptability, it does not allow for discussion of the full political and social implications of climate change, and precludes more radical responses. 相似文献
948.
To analyze the factors affecting US public concern about the threat of climate change between January 2002 and December 2013, data from 74 separate surveys are used to construct quarterly measures of public concern over global climate change. Five factors should account for changes in levels of concern: extreme weather events, public access to accurate scientific information, media coverage, elite cues, and movement/countermovement advocacy. Structural equation modeling indicates that elite cues, movement advocacy efforts, weather, and structural economic factors influence the level of public concern about climate change. While media coverage exerts an important influence, it is itself largely a function of elite cues and economic factors. Promulgation to the public of scientific information on climate change has no effect. Information-based science advocacy has had only a minor effect on public concern, while political mobilization by elites and advocacy groups is critical in influencing climate change concern. 相似文献
949.
Increasing demand for seafood and the lack of growth of capture fisheries have boosted aquaculture growth worldwide. However, European aquaculture has been stagnating over the past decade, and European public authorities have been developing policies and strategies in efforts to reverse this. Aquaculture discourses in the European Union, based on 34 policy, planning, and strategy documents, are examined and a discourse analysis conducted following Bacchi’s WPR (What is the Problem Represented to be?) approach. How the problems in these discourses are represented, the tensions among main objectives, and the implicit assumptions are unveiled, and discussed employing a Polanyian theoretical framework. Taking these assumptions for granted leads to a disembedded understanding of aquaculture, and facilitates the privatization of aquatic space and resources. The analysis contributes to the literature establishing the link between the expansion of aquaculture and the enclosure of aquatic resources and enriches environmental and political debates on European aquaculture. 相似文献
950.
Michael J. Manfredo Jeremy T. Bruskotter Tara L. Teel David Fulton Shalom H. Schwartz Robert Arlinghaus Shigehiro Oishi Ayse K. Uskul Kent Redford Shinobu Kitayama Leeann Sullivan 《Conservation biology》2017,31(4):772-780
The hope for creating widespread change in social values has endured among conservation professionals since early calls by Aldo Leopold for a “land ethic.” However, there has been little serious attention in conservation to the fields of investigation that address values, how they are formed, and how they change. We introduce a social–ecological systems conceptual approach in which values are seen not only as motivational goals people hold but also as ideas that are deeply embedded in society's material culture, collective behaviors, traditions, and institutions. Values define and bind groups, organizations, and societies; serve an adaptive role; and are typically stable across generations. When abrupt value changes occur, they are in response to substantial alterations in the social–ecological context. Such changes build on prior value structures and do not result in complete replacement. Given this understanding of values, we conclude that deliberate efforts to orchestrate value shifts for conservation are unlikely to be effective. Instead, there is an urgent need for research on values with a multilevel and dynamic view that can inform innovative conservation strategies for working within existing value structures. New directions facilitated by a systems approach will enhance understanding of the role values play in shaping conservation challenges and improve management of the human component of conservation. 相似文献