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71.
利用多台资料对比震相识别方法,采用台网中心对地震较精确的定位结果,对南北地震带强化观测台网中心所记录到的地方震、近震、远震分别进行分析。结果表明,随着不同构造区域介质的差异性,地震波传播路径不同,导致各地区所记录到的地震震相特征不同。通过对不同区域地震震相特征的进一步对比分析,找出各区域震相特征的差异性和规律性,为以后台网中对震相识别和精确定位都有一定意义。 相似文献
72.
国土资源管理中遭遇的资源供需矛盾、利益协调困难、违法违规反弹、粗放浪费严重等问题,只是保障发展、保护资源"两难"局面的一些表象,更深层次的原因应从体制、机制、法制的缺陷中探寻,最基础的前提就是要提高国土资源文化的软实力。新媒体时代下,国土资源文化建设通过互联网站、手机报、微博等新媒体手段及报纸、杂志等传统媒介平台进行传播,不断为国土资源事业的改革发展提供强大的精神动力和舆论支持。 相似文献
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林地是维护生态安全,实现区域可持续发展的根本基础资源。林地变化可能导致一些生态环境问题,包括土壤侵蚀,水资源短缺,干旱加剧以及生物多样性的丧失。本文以景观生态学和逻辑回归模型为基础,探讨了京津冀地区1985-2000期间林地变化的时空格局及其影响因素。格局分析结果表明,林地景观破碎化正在下降和林地形状变得越来越规则。通过建立Logistic回归模型,这项研究旨在探讨这一区域1985-2000期间林地变化的重要变量。对于京津冀地区1985-2000期间林地变化而言,土壤有机质含量,坡度(5°),到最近村庄的距离以及人均国内生产总值是最重要的解释变量。研究表明,空间异质性会影响到林地变化的逻辑回归模型的可预测性。 相似文献
75.
In the past decade, polar bears have become the poster species of climate change. But in March 2013, a joint proposal by the governments of the United States and the Russian Federation to up-list polar bears to Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) diverted public attention from climate change towards the hunting of polar bears. Prior to a vote on the proposal, non-governmental organisations spear-headed a media campaign to support the up-listing. In the United Kingdom the campaign received support from celebrities and was widely reported in English language news media. Narratives of commercial legal and illegal polar bear hunting and the imminent extinction of polar bears were aggressively promoted, rhetorically supported by the manipulation of trade and scientific data. By rendering discourses of commercial hunting and a lucrative global trade in polar bear parts highly visible, sustainable hunting and climate change-induced habitat loss were rendered invisible. Media reports of commercial hunting de-coupled polar bear conservation from climate change mitigation, and disassociated polar bear hunting from regulated indigenous subsistence practices. A review of current polar bear conservation measures and an analysis of media coverage leading up to the CITES decision reveal these conflicting discourses, and suggest that more nuanced media coverage of polar bear conservation is necessary if appropriate multilateral conservation policies are to be enacted and publicly supported. 相似文献
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The lack of ambitious climate change policies in large anglophone countries, such as the United States, has been explained by the strong media presence of denialist arguments against climate science. Such counterarguments are less visible in the news media of most European countries. Why do many of these countries nevertheless fail to enact ambitious climate change policies? This paper suggests that influential organizations may block ambitious climate change policies in corporatist countries without an extensive media strategy or a strong denialist message. We draw from theories on the policy process, policy networks, influence strategies, and comparative politics to formulate hypotheses about the existence, influence, and strategies of organizations that oppose ambitious climate policy. We test these hypotheses using an original combination of media data and survey data on the national climate policy network in Finland, a corporatist European country that has long lacked ambitious climate policies. The findings show that a coalition that prioritizes economic competitiveness over climate change mitigation is influential and occupies a central position in the policy network. This pro-economy lobby does not question the validity of climate science or actively seek media visibility. Rather, it influences the policy process using other strategies, such as inside lobbying, and appears in the news media less often than other climate policy organizations. Our results suggest that opponents of climate change mitigation can be powerful despite a weak media presence. This implies that studies on climate politics should pay more attention to strategies of influencing beyond the media spotlight. 相似文献
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