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431.
When extreme weather events occur, people often turn to social media platforms to share information, opinions and experiences. One of the topics commonly discussed is the role climate change may or may not have played in influencing an event. Here, we examine Twitter posts that mentioned climate change in the context of three high-magnitude extreme weather events – Hurricane Irene, Hurricane Sandy and Snowstorm Jonas – in order to assess how the framing of the topic and the attention paid to it can vary between events. We also examine the role that contextual factors can play in shaping climate change coverage on the platform. We find that criticism of climate change denial dominated during Irene, while political and ideological struggle frames dominated during Sandy. Discourse during Jonas was, in contrast, more divided between posts about the scientific links between climate change and the events, and posts contesting climate science in general. The focus on political and ideological struggle frames during Sandy reflects the event’s occurrence at a time when the Occupy movement was active and the 2012 US Presidential Election was nearing. These factors, we suggest, could also contribute to climate change being a more prominent discussion point during Sandy than during Irene or Jonas. The Jonas frames, meanwhile, hint at lesser public understanding of how climate change may influence cold weather events when compared with tropical storms. Overall, our findings demonstrate how event characteristics and short-term socio-political context can play a critical role in determining the lenses through which climate change is viewed.  相似文献   
432.
A study was carried out in district Samba of Western Himalayan province of Jammu and Kashmir of India.The data were collected in an interview schedule in personal interview with 180 household heads.The association between the level of fuelwood consumption(low versus high consumption) and different factors,each individually,was investigated using chi-square test of association at 0.001 level of significance.It was found that out of 25 socio-economic,biophysical and alternate fuel factors,15 factors(each individually) significantly influenced the domestic fuelwood consumption.Logistic regression models of alternate fuel use,social,economic and biophysical factors were developed to identify key variables influencing fuelwood consumption levels within each respective category.A composite model was also developed to identify key factors when all variables in all the pre-said categories were considered simultaneously.Surprisingly,in contrast to expectation the model with alternate fuel use did not provide a good fit.The biophysical model also did not provide a good fit.The economic and composite models were the same with equal level of accuracy of predication.This implies that economic aspects,rather than the availability of alternate fuels,dominate fuelwood consumption levels of rural households.Strategies to increase the exposure of the head of household to outside world needs to formulated to reduce the domestic fuelwood consumption levels.Households nearer to state forests are to be educated about efficient use of fuelwood and be encouraged to intensify use of Liquified Petroleum Gas.The wider implications of study are:the availability of alternate fuels is not a necessary condition to decrease household level domestic fuelwood consumption.Economic factors needs to be considered in designing strategies to reduce fuelwood consumption.Increased employment opportunities would increase the opportunity cost of fuelwood collection and this would reduce its use.  相似文献   
433.
Protected areas are currently the primary strategy employed worldwide to maintain ecosystem services and mitigate biodiversity loss. Despite the prevalence and planned expansion of protected areas, the impact of this conservation tool on human communities remains hotly contested in conservation policy. The social impacts of protected areas are poorly understood largely because previous evaluations have tended to focus on one or very few outcomes, and few have had the requisite data to assess causal effects (i.e. longitudinal data for protected and control sites). Here, we evaluated the short-, medium- and long-term impacts of marine protected areas (MPAs) that were specifically designed to achieve the dual goals of conservation and poverty alleviation (hereafter “integrated MPAs”), on three key domains of poverty (security, opportunity and empowerment) in eight villages in North Sulawesi, Indonesia. Using social data for villages with and without integrated MPAs from pre-, mid- and post-the five-year implementation period of the integrated MPAs, we found that the integrated MPAs appeared to contribute to poverty alleviation. Positive impacts spanned all three poverty domains, but within each domain the magnitude of the effects and timescales over which they manifested were mixed. Importantly, positive impacts appeared to occur mostly during the implementation period, after which integrated MPA activities all but ceased and reductions in poverty did not continue to accrue. This finding questions the efficiency of the short-term approach taken in many international donor-assisted protected area projects that integrate development and conservation, which are often designed with the expectation that project activities will be sustained and related benefits will continue to accumulate after external support is terminated.  相似文献   
434.
提出全球气候变化与世界社会经济动荡等变化环境下流域可持续发展的科学内涵、制约因素以及解决途径。以自然与社会协同进化的复杂系统作为变化环境下流域概念的抽象表征,以科研能力与管理能力作为流域可持续发展的重要影响因素,以流域管理中科学研究与管理实践的相互作用机理为出发点,分析当前流域管理中科学研究与管理实践的种种错位,提出适应变化环境的流域管理知识创新机制,为提高流域科研水平、充分发挥科学在流域可持续发展中的作用提供理论支撑。  相似文献   
435.
The Dominican fishing community of Buen Hombre is struggling to reconcile its fishing activities with the state of the coral reef ecosystem on which it depends. The ecosystem is showing signs of deterioration, and this seems to be resulting in large part because of the fishing activities of the Buen Hombre fishermen. The institutional arrangements of the fishermen themselves, and of relevant external organizations, have not kept pace with important technological and demographic changes that have affected the community. This paper presents the results of an analysis that unpacks these processes via a statistical analysis of fishermen behavior and a social network analysis of the “cofishing” network that these fishermen constitute. The statistical analysis shows that gear choice is very important in explaining the amount of fish caught, both as a direct factor and as a mediator of other factors such as membership in the local fishermen's association. The social network analysis complements this result by demonstrating that gear choice also serves to segment the fishermen into separate groups, with few direct linkages between them. The resulting gear-based fragmentation of the community is seen to have negative implications for the ability of the fishermen to act collectively to conserve their fishery. The paper concludes with some thoughts and suggestions for how the community might move forward, including expanding the membership of the fishermen's association and strengthening ties between fishing groups as well as ties between the community and relevant governmental agencies.  相似文献   
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