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111.
After 50 years of steady increase, per capita visits to US national parks have declined since 1988. This decline, coincident with the rise in electronic entertainment media, may represent a shift in recreation choices with broader implications for the value placed on biodiversity conservation and environmentally responsible behavior. We compared the decline in per capita visits with a set of indicators representing alternate recreation choices and constraints. The Spearman correlation analyses found this decline in NPV to be significantly negatively correlated with several electronic entertainment indicators: hours of television, (rs=-0.743, P<0.001), video games (rs=-0.773, P<0.001), home movies (rs=-0.788, P<0.001), theatre attendance (rs=-0.587, P<0.025) and internet use (rs=-0.783, P<0.001). There were also significant negative correlations with oil prices (rs=-0.547, P<0.025), foreign travel (rs=-0.452, P<0.05), and Appalachian Trail hikers (rs=-0.785, P<0.001). Income was significantly positively correlated with foreign travel (rs=0.621, P<0.005) but negatively correlated with national park visits (rs=-0.697, P<0.005). There was no significant correlation of mean number of vacation days, indicating available vacation time is probably not a factor. Federal funding actually increased during this period, and so was rejected as a probable factor. Park capacity was rejected as limiting since both total overnight stays and visits at the seven most popular parks rose well into the mid-1990s. Aging of baby boomers was also rejected as they are only now reaching retirement age, and thus during the period of visitation decline were still of prime family vacation age. Multiple linear regression of four of the entertainment media variables as well as oil prices explains 97.5% of this recent decline (r=0.975, multiple r2=0.950, adjusted multiple r2=0.925, SE=0.015, F=37.800, P<0.0001). We may be seeing evidence of a fundamental shift away from people's appreciation of nature (biophilia, Wilson 1984) to 'videophilia,' which we here define as "the new human tendency to focus on sedentary activities involving electronic media." Such a shift would not bode well for the future of biodiversity conservation.  相似文献   
112.
袋式除尘用过滤材料的性能测试与对比   总被引:2,自引:0,他引:2  
针对袋式除尘用过滤材料选用时的低阻、高效要求,对PPS、P84、FMS9806、PPS覆膜、FMS9806覆膜、HBT等6种常用的过滤材料的过滤效率、过滤阻力等性能指标进行测试与对比.测试结果表明:HBT的过滤效率较高,仅次于FMS9806覆膜,且过滤阻力较低;FMS9806覆膜滤料的过滤效率明显高于其他过滤材料,但阻力也是最高的;其余过滤材料的过滤效率均低于这2种材料,同时阻力相对较高.  相似文献   
113.
新型溴系阻燃剂(NBFRs,novel brominated flame retardants)作为传统溴系阻燃剂的替代品已广泛应用于电子产品、纺织品、家具等商品中,随着这些商品的生产、使用和处置,NBFRs不可避免地释放到环境中,给环境和人体带来潜在的危害.部分NBFRs可通过摄食和呼吸作用进入人体对人体产生一定危害...  相似文献   
114.
This study examines domestic media’s coverage of foreign wildfires from a climate change perspective. It explores Swedish newspapers’ coverage of wildfires in Australia, the Mediterranean region, and the USA during a three-year period (February 2013–March 2016), focusing on how and to what extent climate change is viewed as an underlying cause. A central result is that climate change is mentioned far more often in the case of Australian wildfires than of fires in the other two regions. Another finding is that the climate change issue became more prominent after a severe domestic wildfire in 2014. These observations are also examined qualitatively through a combined frame and discourse study where the importance of foreign news values, the use of foreign sources, cultural proximity/distance, and domestication procedures are analysed. In conclusion, foreign, domestic, and cultural factors in climate change reporting in relation to extreme events are further discussed.  相似文献   
115.
Over the past decade, scientists and journalists have prominently utilized the metaphor of a tipping point for drastic, irreversible and dangerous climate change. This paper shows how the tipping point metaphor became a multi-purpose bridge between science and the news media, describing how its meaning and use developed and diversified in interaction between these two domains. Within the scientific domain, the metaphor developed from a rhetorical device conveying a warning of drastic, irreversible and dangerous climate change to a theoretical concept driving empirical research. The news media soon picked up the tipping point metaphor for abrupt and dangerous climate change, turning it into a common part of the journalistic lexicon. Moreover, both science and the news media developed another, societal use of the tipping point metaphor, calling for radical societal change to avoid climate change catastrophe. The tipping point metaphor is hence not a monolithic notion but a highly versatile concept and expression, allowing it to be used for various communicative purposes by distinct stakeholders in different contexts.  相似文献   
116.
Some extreme weather events may be more likely to affect climate change beliefs than others, in part because schema individuals possess for different events could vary in encouraging such links. Using a representative sample of U.S. adults and geocoded National Weather Service data, we examine how a range of extreme weather event categories relate to climate change beliefs, and the degree to which individuals’ self-reported experiences are shaped by their political views across event types. For tornado, hurricane, and flood events, we find no link with beliefs. For polar vortex and drought events, we find that although self-reported experience is linked with climate beliefs, reporting of these experiences is influenced by political identity and partisan news exposure. These findings underscore a limited role for extreme weather experiences in climate beliefs, and show that events more open to interpretation, such as droughts and polar vortex disturbances, are most likely to be seen through a partisan lens.  相似文献   
117.
118.
The article explores the new media’s role in climate change communication in Russia. By providing an open space for the expression of very diverse points of view, the internet creates a substitute media reality where both climate activists and climate sceptics can question the established discourse. Analysis of 374 entries published on the LiveJournal blogging platform has resulted in the identification of four discursive categories: “conspiracies of climate change,” “climate change impact,” “political games of climate change” and “online (anti-)environmentalism.” Each category demonstrates how the same topic can be framed in very different ways depending on bloggers’ worldview rather than the nature of the discussed environmental problem. The findings also show that the blogs act as “echo-chambers” for both climate deniers and climate activists reinforcing their behold beliefs. Finally, the analysis discovers some parallels with the traditional media coverage in their minimal critique of Russian state policy on climate.  相似文献   
119.
A flurry of studies in recent years has analyzed the role of media in climate change communication. This article provides a systematic, large-scale, and up-to-date overview of the objects and characteristics of this research field through a meta-analysis. It identifies 133 relevant studies and analyzes them empirically. The results show that research activity has risen strongly over time, and that the analytical spectrum has expanded to include an increasing number of countries, more types of media including online and social media, and different methodological approaches. The analysis also demonstrates, however, that scholarship in the field still concentrates strongly on Western countries and print media.  相似文献   
120.
采用生物膜流化床工艺对中部某城镇污水处理厂进行提标改造,在冬季水温低于14℃时进行中试研究。取好氧池1和2中的部分填料经小试实验对其中的硝化反应动力学分析,得出填料上相应生物膜硝化反应速率表达式。并通过物料衡算计算出两级生物膜流化床反应器硝化反应动力学模型,经过实际中试实验,测得实际值与计算值相关性较好,其相对误差在15%以下。应用模型在单个反应器为完全混合、整体为推流模式的多级生物膜流化床工艺,得出NH4+-N出水浓度计算表达式。  相似文献   
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