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111.
This article investigates how polar bears were established as icons of climate change in the popular science magazine National Geographic. In a multistep process, anthropomorphized depictions first established polar bears as subjects of identification. Then, polar bears were visually connected to the endangered Arctic. Finally, they emerged as ambassadors of a threatened ecosystem and icons of climate change. I highlight the wider political contexts of this process of iconization and the semiotic and cultural resources on which it draws, showing what kind of climate change communication the polar bear icon enables or inhibits. The icon lends itself to being deployed in visual communication strategies creating personal concern and public awareness for climate change. At the same time, the icon fosters an individualized, emotionalized, and localized account of climate change but does not make its wider causes visible.  相似文献   
112.
Summary. Darna bradleyi Holloway, D. trima Moore, Setothosea asigna van Eecke and Setora nitens Walker are sympatric and coseasonal limacodid moths in plantations of oil palm, Elaeis guineensis Jacq. (Arecales: Palmae), in Borneo, southeast Asia. We tested the hypothesis that these four species maintain reproductive isolation through specificity in diel periods of communication, microlocation for communication and/or communication signal (pheromone). Studying diel periodicity of calling behavior by female moths and response by male moths to traps baited with virgin females or synthetic pheromone, we determined that sexual communication of D. bradleyi and D. trima took place from ˜17:30 to 18:45 hr and that of S. asigna and S. nitens from ˜18:45 to 20:00 hr and from ˜18:30 to 19:30 hr, respectively. Over 80% of male S. asigna and S. nitens were captured in pheromone-baited traps suspended >5 m high, whereas male D. bradleyi and D. trima were captured mostly in traps <5 m high. Synthetic pheromone baits attracted male moths in a species-specific manner. Moreover, baits containing both S. asigna and S. nitens pheromones failed to attract any male moths, indicating that female S. asigna and S. nitens, with overlapping communication periods, use bifunctional pheromone components that attract conspecific males while repelling heterospecifics. Similarly, addition of D. bradleyi pheromone to S. asigna or S. nitens pheromone reduced attraction of male S. asigna and S. nitens. The failure of D. bradleyi and D. trima, which overlap in time and microlocation for communication, to evolve bifunctional pheromones may be attributed to the recent occurrence of sympatry between D. bradleyi and D. trima in Borneo, apparently too recent for bifunctional pheromones to have evolved. We conclude that D. bradleyi, D. trima, S. asigna and S. nitens utilize any or all of diel periodicity, intra and interspecific effects of communication signal and/or microlocation for signaling, allowing these limacodids to co-inhabit the same habitat and remain reproductively isolated. Received 5 May 2000; accepted 18 August 2000  相似文献   
113.
In this paper we examine and compare communication processes aimed at building social networks and increasing citizen engagement in two communities participating in a municipal sustainability planning (MSP) pilot programme in Alberta, Canada, initiated by the Alberta Urban Municipalities Association (AUMA). Data were gathered through qualitative semi-structured interviews and documentary review. In soliciting citizen engagement, each community utilised a variety of communication methods, based on available resources and on-going evaluation of community responses. In both cases, citizens developed a shared vision of a preferred future for their community, aided by a reconfiguration of their internal and external social networks. In addition to drawing upon and strengthening bonding relationships within the community, bridging relationships with external actors and agencies promoted knowledge mobilisation that aided in planning and transitioning towards sustainability. Both communities faced challenges as well, which the authors discuss in relation to the sustainability of MSP planning.  相似文献   
114.
Based on in-depth interviews, this article presents findings of a study centred on public communication regarding Tiengemeten, a Dutch island previously occupied by farmers. An answer is sought to the question of how visitors to Tiengemeten evaluate, according to their own experiences, the discourse of people involved in Tiengemeten from a policy and communication perspective. This study showed that visitors’ experiences do not always match the emotions appealed to in public communication materials. It is also suggested that people involved from a policy and communication perspective should refrain from using ‘heavily value-laden’ phraseology. For reasons of trust, this article suggests aligning public communication with genuine experiences of visitors. This is also necessary for avoiding scepticism of visitors as policy makers and communication professionals run a risk that public communication regarding nature becomes counterproductive.  相似文献   
115.
我国现已收集整理了覆盖全国的各类生物多样性数据和信息,但生物多样性数据管理的技术水平和质量较低,信息交流的技术手段和机制尚不理想,数据管理和信息交流的整体能力建设还相当薄弱。在评述目前我国生物多样性数据管理和信息交流现状的基础上,提出加强我国生物多样性数据管理和信息交流的具体行动措施,即建立新型的国家生物多样性信息系统组织机构体系,建立电子网络化的生物多样性信息系统,建立信息共享机制,优先协调、完善和开发一批数据库,制定基础数据管理标准。  相似文献   
116.
Abstract: Noise may drive changes in the composition and abundance of animals that communicate vocally. Traffic produces low‐frequency noise (<3 kHz) that can mask acoustic signals broadcast within the same frequency range. We evaluated whether birds that sing within the frequency range of traffic noise are affected by acoustic masking (i.e., increased background noise levels at the same frequency of vocalizations reduce detection of vocalization) and are less abundant in areas where traffic noise is loud (44–57 dB). We estimated occupancy, the expected probability that a given site is occupied by a species, and detection probabilities of eight forest‐breeding birds in areas with and without traffic noise as a function of noise and three measures of habitat quality: percent forest cover, distance from plot center to the edge of forest, and the number of standing dead trees or snags. For the two species that vocalize at the lowest peak frequency (the frequency with the most energy) and the lowest overall frequency (Yellow‐billed Cuckoo [Coccyzus americanus] and White‐breasted Nuthatch [Sitta carolinensis]), the presence of traffic noise explained the greatest proportion of variance in occupancy, and these species were 10 times less likely to be found in noisy than in quiet plots. For species that had only portions of their vocalizations overlapped by traffic noise, either forest cover or distance to forest edge explained more variation in occupancy than noise or no single variable explained occupancy. Our results suggest that the effects of traffic noise may be especially pronounced for species that vocalize at low frequencies.  相似文献   
117.
Robert Coates 《Disasters》2021,45(1):86-106
Disaster education outcomes are highly dependent on the political context of that education. Based on a rich, in‐depth case study of the creation of community monitors in a landslide and flood‐prone city in southeast Brazil, this paper demonstrates how developmental and political environments add much additional nuance to existing theories of behaviourist and transformative education for disaster preparedness and mitigation. Beyond identifying the benefits of education, it argues that disaster risk reduction outcomes are reliant on governance frameworks that alter over time. The study reveals the political complexity associated with programme implementation and cites the perspectives of a number of participants. Disaster education is shown to be the necessary yet underappreciated twin of the militarised and technical approaches that dominate disaster response in Brazil. Understated, however, is education's situatedness: how it can become an arena of conflict between government and civil actors over matters of state and society in increasingly hazardous urbanisation settings in Latin America.  相似文献   
118.
在4G基站快速增加的背景下,基站共站已成为较为普遍的架设方式.根据移动通信基站的发展趋势和工作原理,选取典型共站的移动通信基站,按照测量规范进行布点,了解基站周围电场强度的大小、楼顶架设基站的建筑物内部电场强度,以及周围建筑物室内的电场强度垂直方向的变化规律.分析结果表明,只要基站选址合理,天线面板角度与高度能尽量避开周围环境保护目标的方向,共站的基站运营时周围环境的电磁辐射水平可以满足相应的评价标准,不会对周围的环境造成明显的影响.  相似文献   
119.
巢清尘 《灾害学》2000,15(3):79-84
在概述我国交通运输的构成以及这年发展的基础上,分析了不同气候异常类型对不同交通运输系统在不同阶段的影响,提出了交通运输防御气候异常的战略性对策和在不同气候异常情况下防御气候灾害的战术性对策。  相似文献   
120.
The election as US President of Donald J Trump, who denies the scientific consensus on climate change, raises questions about the role of scientists in public discourse. How far should scientists wade into the waters of advocacy before risking their credibility of fair arbiters of knowledge? The new study by Kotcher, Myers, Vraga, Stenhouse, and Maibach [2017. Does engagement in advocacy hurt the credibility of scientists? Results from a randomized national survey experiment. Environmental Communication. doi:10.1080/17524032.2016.1275736] is a reminder that scientists are among the most trusted people in public life and have some freedom to engage publicly without harming their reputation. However, with the power to influence public debate comes the responsibility to carefully consider the impact of statements and actions. This commentary discusses the challenges facing scientists at a time of great potential for public engagement, and for a gap between perceived and actual intent of public statements.  相似文献   
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