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121.
灾害作用于人类社会后成为灾难, 从而兼具了自然属性和社会属性. 本文侧重灾害的社会属性, 分析日本近现代地震灾害的社会影响趋势变迁, 指出日本在不断总结灾害应对经验的基础上逐步完善了防灾减灾体制, 其防灾减灾水平在不断提高, 但是由于生活方式日益城市化, 灾害越来越具有多样性、 连锁性的特征. 在日本, 地震后的核安全不是新问题, 但是由于缺乏前瞻性以致核危机扩大. 日本的经验提醒面临社会急剧变迁的我们, 防灾减灾需要考虑到社会变迁的前瞻性制度建设. 相似文献
122.
The Hawaii bibliographic database has been created to contain all of the literature, from 1779 to the present, pertinent
to the volcanological history of the Hawaiian-Emperor volcanic chain. References are entered in a PC- and Macintosh-compatible
EndNote Plus bibliographic database with keywords and abstracts or (if no abstract) with annotations as to content. Keywords
emphasize location, discipline, process, identification of new chemical data or age determinations, and type of publication.
The database is updated approximately three times a year and is available to upload from an ftp site. The bibliography contained
8460 references at the time this paper was submitted for publication. Use of the database greatly enhances the power and completeness
of library searches for anyone interested in Hawaiian volcanism.
Received: 1 June 1997 / Accepted: 17 September 1997 相似文献
123.
Dissolved aluminium (Al) is generally at low concentrations in neutral freshwater due to its insolubility. However, a fall in pH resulting from acid deposition and mining alters the mobility of Al and so entry to adjacent neutral waters. The present study examines the environmental behaviour, cell-associated surface adsorption/absorption and toxicity of Al at neutral pH to the alga Chlamydomonas gigantea in the presence and absence of the key Al-binding ligand silica. We then examined transfer of Al from C. gigantea to the planktonic crustacean Daphnia pulex. Finally, the effect of Al on the elemental composition (and hence nutritional value) of the two organisms was compared to unexposed controls. C. gigantea increased the amount of Al in the algal culture medium. Binding of Al to extracellular glycoprotein is probably the reason why only one-third of the biosorbed Al was absorbed (accumulated) by C. gigantea. Aluminium concentrations between 50 and 500 μg l−1 reduced growth of C. gigantea at 16 days exposure to the metal. Silica reduced biosorption, accumulation and toxicity of Al by C. gigantea. The concentration of Al in D. pulex fed Al-contaminated C. gigantea for 16 days did not differ from those fed alga grown in the absence of added Al. C. gigantea contaminated with Al contained less sulphur, magnesium, potassium and sodium although only sulphur fell in D. pulex subsequently fed the contaminated alga. Chloride, calcium, iron and silicon were significantly higher in D. pulex. 相似文献
124.
125.
Laura Pereira 《Singapore journal of tropical geography》2010,31(3):384-400
Coca is a controversial plant, existing on the boundary between legality and illegality. This study aims at providing an analytical technique for discussing the problematic of coca in Colombia. Using new theoretical propositions in human geography, a more‐than‐human approach is adopted to encounter coca holistically. The results are a narrative account of coca's social life as experienced by the researcher following its network of non‐cocaine derivatives. An analytical section invokes the Foucauldian dispositif to the drug trade and utilizes concepts of informed materials and technological zones to describe coca outside a political economy discourse. The research finds that coca's dynamic materiality complicates it as a commodity and that these conventional approaches do not fully encapsulate this complexity. By grappling with the messiness of coca's materiality, this paper reveals the multiplicity and interplay of coca's definitions, which lie at the heart of many conflicts. 相似文献
126.
Katarzyna Wojczulanis-Jakubas Dariusz Jakubas Nina J. Karnovsky & Wojciech Walkusz 《Polar research》2010,29(1):22-29
A dual foraging strategy (long versus short trips) has been described for some species of seabirds, such as petrels, albatrosses (Procellariiformes) and penguins (Sphenisciphormes). Such a strategy has recently been reported for little auks ( Alle alle ) from the central coast of west Spitsbergen, Svalbard. This has been explained as a response to poor trophic conditions close to the breeding colony, and better conditions further away (150 km). In the present study, we investigated the foraging strategy of little auks in Hornsund, southern Spitsbergen, during two seasons with contrasting oceanographic conditions. During 2004, foraging conditions for little auks were good: cold Arctic waters rich in profitable high-energy food were dominant in their feeding grounds. Conversely, during 2006 there was a great influx of warm Atlantic water in the feeding area, inducing poor foraging conditions. In both seasons we examined the pattern of foraging trip lengths automatically with a video camera (both adults from four nests in each year), and by direct non-stop observation of 20–54 individually marked birds. Our results showed that the dual strategy and the ratio of short and long trips were consistent, regardless of the conditions in the feeding grounds. This suggests that the strategy is inherent and may be crucial for the self-maintenance of adults. 相似文献
127.
强震发生前, 震源附近的地震活动往往会呈现出一些空间和时间的异常特征, 分析和提取这些异常特征的方法较多。 本文采用了与常规强震预测方法迥异的地震预测方法地震活动反向追踪法(Reverse Tracing of Precursors, RTP), 对中国大陆近30年来的几个MS≥7.5大震(含2008年5月12日汶川MS8.0地震)进行了探索性的回溯研究。 结果表明, 该方法在中国大陆大震预测方面有一定的适用性, 并利用该方法对中国大陆地区的未来强震活动做了一定的预测。 相似文献
128.
2008年5月12日T14:28汶川发生8.0级大地震,2008年5月13日T5:00江苏省发生滨海ML3.8地震。滨海地震是否是由汶川地震触发的、可指示滨海附近中短期内将发生中强地震的"诱发前震"?基于此,本文进行了如下研究:①统计南北地震带及中国台湾7.3级以上、日本7.5级以上大地震;②统计①中大震发生后3天时间(72 h)内,华北中南部地区发生的M_L 3以上地震;③统计大震发生后1年内在M_L 3地震附近地区(距震中350 km以内)发生的5级以上地震;④对上述3组地震是否存在链式关系进行统计研究,即研究特定条件下的A—F—B链式地震现象在华北中南部的预报效果。研究结果表明:根据目前所拥有的统计资料,无法确定2008年5月13日滨海M_L 3.8地震是由汶川8级地震诱发的"前兆地震"。 相似文献
129.
This study analyses the temporal clustering, spatial clustering, and statistics of the 2012–2013 Torreperogil-Sabiote (southern Spain) seismic swarm. During the swarm, more than 2200 events were located, mostly at depths of 2–5 km, with magnitude event up to mbLg 3.9 (Mw 3.7). On the basis of daily activity rate, three main temporal phases are identified and analysed. The analysis combines different seismological relationships to improve our understanding of the physical processes related to the swarm's occurrence. Each temporal phase is characterized by its cumulative seismic moment. Using several different approaches, we estimate a catalog completeness magnitude of mc≅ 1.5. The maximum likelihood b-value estimates for each swarm phase are 1.11 ± 0.09, 1.04 ± 0.04, and 0.90 ± 0.04, respectively. To test the hypothesis that a b-value decrease is a precursor to a large event, we study temporal variations in b-value using overlapping moving windows. A relationship can be inferred between change in b-value and the regime style of the rupture. b-values are indicators of the stress regime, and influence the size of ruptures. The fractal dimension D2 is used to perform spatial analysis. Cumulative gamma and beta functions are used to analyse the behaviour of inter-event distances during the earthquake sequence. 相似文献
130.