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51.
Olivier Rubin 《Disasters》2020,44(2):239-261
Natural hazards not only have socioeconomic ramifications, they also have political repercussions. This paper takes stock of the fast-growing area of research linking disasters triggered by natural hazards to voting behaviour. It is based on the central tenet of voter retrospection: voters place emphasis on past events when making their selection. The study uncovers a great disparity in analysis of electoral outcomes in the wake of disasters, part of which can be explained by the different methodological choices of authors. However, the unpredictability of voting behaviour in the aftermath of disasters also points to the relevance of introducing an intermediate variable when elucidating voter movements. This variable should capture the prevailing political discourses that surround disasters, as these are likely to shape the dynamics of voter retrospection. The paper demonstrates the analytical relevance of such political discourses by contrasting political dynamics in Denmark and Sweden following the Indian Ocean tsunami on 26 December 2004.  相似文献   
52.
紫羊茅(Festucarubra)抗铜品种Merlin和敏感品种559种子在水中吸胀5d后长出的幼苗在一般培养液中分别培养了0、2、4、6、8和10d(分别称为D0、D2、D4、D6、D8和D10)后再置于ρ(Cu2+)=5mg/L的相同培养液中,其中约一半培养至d20,其余至d27.结果与同龄的幼苗相比,MerlinD6在27d和20d的根中均有最高的干物质含量和最大的叶绿素浓度;在27d苗的根中铜积累了最少;而MerlinD6的苗在各个抗性处理组中最高在从20d至27d的培养期间,MerlinD6地上部分的干物质增加最多,而根中则减少最多,叶绿素含量也减少最多,在根中积累的铜也最少;可是在敏感的S59中则没有这种特殊现象,这些现象暗示,即使是在抗性品种的Merlin中,在其不同的生长时期经铜处理,也表现出不同的抗性,并可能有一个抗性最大的生长期。  相似文献   
53.
选择0#柴油和平湖原油乳化液对缢蛏(Sinonovacula constricta)进行氧化胁迫实验,选取典型的抗氧化酶-超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷光甘肽硫转移酶(GST)及过氧化物酶(POD)用于衡量油类污染物对生物体造成的氧化压力大小.此外,结合综合生物标志物响应(Integrated Biomarker Responses,IBR)指标,对2种石油污染物对缢蛏的毒性响应进行定量化评价.结果表明,不同浓度的0#柴油和平湖原油对缢蛏消化腺中的4种酶表现出不同程度的诱导效应,各试验组在暴露前期均表现出诱导或抑制,但对4种酶的影响存在时间顺序性,SOD、CAT和GST的酶活性表现为升高-降低的过程,POD表现为降低-升高的过程,活性达到峰值的时间SOD和CAT要早于GST和POD.结合计算出的IBR数值来看,高浓度0#柴油能够引起最为显著的生物效应变化,显示该石油污染物高毒性的特征,0#柴油生物毒性大于平湖原油生物毒性.  相似文献   
54.
Climate change vulnerability is disproportionately distributed between different population segments in society. This study qualitatively explores how key stakeholders in municipalities (i.e. planning and operational staff in municipalities and the vulnerable themselves) construct social vulnerability in relation to climate change with a specific focus on thermal stress (i.e. heat waves) and which adaptive responses they identify at different levels. The empirical material consists of five focus groups with actors in a large Swedish municipality where the “Vulnerability Factor Card Game” was used as stimulus material to create 10 fictional individuals. The results show that there is a substantial amount of local knowledge about vulnerability drivers and inter-relations between social factors and vulnerability. Local decision-makers also defined a wide range of possible adaptation measures at different municipal levels. Our study clearly indicates that contextualised knowledge, which could complement the quantitative approaches in research, is abundant among municipal planners, staff employed at municipal operations such as health care, and among the vulnerable themselves. This knowledge remains untapped by research to a great extent and only seems to have an insignificant influence on policy-making. In particular, how impacts vary between different social and demographic groups and how adaptation strategies that target the most vulnerable could be defined are of great interest. The present study clearly indicates that social hierarchy may produce increased inequality in the specific context of climate change, vulnerability and adaptive responses at different levels.  相似文献   
55.
ABSTRACT. Studies were conducted to determine the distribution of fish in the New and East Rivers in relation to thermal discharges from Appalachian Power Company's fossil fuel plant at Glen Lyn, Virginia. Over 15,300 specimens representing 41 species were collected with seines, electrogear and rotenone at six sampling locations from February, 1973 to October 1973. Sampling frequency was designed to evaluate the effects of ambient temperature upon preferred temperature. Diversity indices were calculated for each location. There was a slight decrease in the diversity indices for those stations located in the thermal discharge. Condition coefficients calculated for Notropis albeolus Jordan, Notropis rubellus Aqasaiz, Notropis spilopterus Cope, Ictalurus punctatus Rafinesque, and Etheostoma blennioides Rafuesque were found to be significantly (p =.05) lower in the thermal discharge for all species tested except E. blennioides. Temperatures were plotted against frequency of capture to determine a particular species temperature selection from field data and indicated that: (1) Some species avoided high temperatures (i.e., Curnpostoma anomalum Rafuesque). (2) Some species were attracted to high temperatures (i.e., Ictalurus punctatus). (3) Some species distribution was not effected by temperatures (i.e., Notropis spilopterus).  相似文献   
56.
采用生物行为传感器监测青鳉鱼在重金属铜暴露下的行为数据,分析不同暴露浓度(20、10、5、1和0.1 TU)下青鳉鱼的行为响应。20、10、5、1和0.1 TU的暴露浓度下青鳉鱼对重金属污染的行为反应模式符合环境胁迫阈值模型,且不同浓度梯度重金属对青鳉鱼产生不同的行为毒性效应。利用重金属作用下青鳉鱼的行为变化来研究重金属环境胁迫导致的生物行为响应机制,从而得到重金属暴露下生物行为的实时变化过程和趋势,可对水环境生态系统质量进行综合评价。  相似文献   
57.
目的 研究一类硬质泡沫弹架结构的蠕变特性和贮存寿命评估方法.方法 通过测定贮存恒定应力水平下该型硬质泡沫弹架的温度加速蠕变性能数据,建立泡沫弹架材料的蠕变本构关系,研究泡沫弹架材料的蠕变时温等效规律.在此基础上,开展泡沫弹架的高温加速贮存试验与评估方法研究.结果 在高温蠕变试验后,该型硬质泡沫材料的本构关系及压缩特性均...  相似文献   
58.
Climate change strongly affected the structure and functions of natural ecosystems,e.g.the vegetation productivity decreased in the Northeast permafrost region due to the higher temperature and less precipitation,whereas in the Tibetan Plateau,the vegetation productivity increased,owing to the improved thermal resource.Climate change led to reduced precipitation in North and Northeast China and thus the reduced surface runoff.The public needs for energy were changed because of climate change,e.g.the shorter heating period in winter.Climate change profoundly influenced human health,pathophoresis and major projects by increasing extreme events,including frequency and magnitude,and causing more serious water shortage.Under the background of climate change,although the improved thermal resources can be helpful for extending the crop growth period,more extreme events may resulted in more instability in agricultural productivity.Not only did climate change indirectly affect the secondary and tertiary industries through the impacts on agriculture and natural resources,but also climate change mitigation measures,such as carbon tax,tariff and trading,had extensive and profound influences on the socioeconomic system.Further analysis indicated that the impact of climate change presented significant regional differences.The impact had its pros and cons,while the advantages outweighed the disadvantages.Based on the above analysis on the impacts of climate change,we put forward suggestions on coping with climate change.First,scientifically dealing with climate change will need to seek advantages while avoiding the disadvantages of climate change in order to achieve the orderly adaptation to climate change,which is characterized with"Overall best,long-term benefit."Second,quantitative adaptation should be given more attention,e.g.proposing operational schemes and predictable goals and using uncertainty analysis on adaptation measures.Third,more active coping strategy should be adopted to enhance China's future comprehensive competitiveness.The strategies include but are not limited to gradually adjusting the industrial structure,intensifying the research and development(RD)of emission reduction technology and actively responding to the influence of carbon tax,tariff and trading on socioeconomic development in China.  相似文献   
59.
2005~2010年我国自然灾害救助应急响应的时间变化特征   总被引:1,自引:0,他引:1  
自然灾害救助应急响应是减轻自然灾害风险的重要途径,也是政府的重要职责,2005年被纳入《国家自然灾害救助应急预案》,反映了我国自然灾害救助工作的发展变化和“以预防为主”的应急管理新思路。收集整理2005~2010年国家启动的历次自然灾害救助应急响应情况,对应急响应的时间变化特征进行分析讨论。结果表明:(1)2005~2010年,国家共针对130次重大灾害事件启动应急响应235次,各级别响应的比例与灾害发生的频次比例相当;(2)近年应急响应以洪涝、台风及其引发的滑坡和泥石流灾害为主,高发重发期在汛期(6~9月),尤以7月为最;而旱灾、低温冷冻和雪灾以及风雹灾害的关键期分别为春夏秋三季、冬春季节和春末夏初;(3)应急响应特征研究启示减灾救灾工作要因时、因地、因灾制宜,并加快基于过程的灾害风险评估和脆弱性机理研究等 .  相似文献   
60.
Kılıç GA 《Chemosphere》2011,83(8):1175-1180
This study investigated biomarker responses of the earthworm Lumbricus terrestris in order to evaluate the soil pollution along Porsuk River Basin. Samples consisted of animals from six sites that are agricultural regions and a forested control. Histopathological and biochemical alterations were examined. Significant histopathological alterations were observed in animals from three of the sampling sites. There was an enlargement of epithelial cell lining, mucus cell hyperplasia and increase in mucus secretion. Circular and longitudinal muscles lost their structural integrity. Chloragogenous tissue was dilated and vocuolized. Necrosis was observed in the cells and tissues of some affected worms. A load of heavy metals in tissues of animals was determined. Heavy metals were found to be accumulated particularly in longitudinal muscles of animals. CAT activity was found to be increased in animals from three of the experimental sites. GST activity was also increased in five sites while it was stable in one site. The results have shown that animals from locations particularly that are close to urbanized and industrialized regions were seriously affected from the soil pollution around the basin. These results are reflecting the biological effects of soil pollution around Porsuk River Basin on the indicator organism L. terrestris and constitute an early warning of ecological change in relation to human health.  相似文献   
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