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1.
2008年"5·12"汶川大地震后,我国出现了前所未有的诗歌大潮,以此为契机,向我国古代诗歌纵深领域延伸,对我国古代地震诗歌进行初步探析。本文通过梳理我国各个文学时期的地震诗歌代表作,归纳出古代地震诗歌在内容上的共同特点:即,宏观描写地震景况和关注个体生命并存;将地震灾害与当朝政治密切联系并以此警示、改良政治;能够意识到人自身抗击灾害的力量并表现出可贵的乐观和自信。  相似文献   

2.
本文通过对汶川8.0等多次大地震前后气候、森林、植被等因素强烈变化的对比研究,表明地震对生态环境的严重破坏给人类、动植物等带来巨大灾害。地震灾害可能影响和破坏生态环境,而某些生态环境的改变也可能为地震预报预测研究提供重要的震兆信息。同时,重视环境保护环境是非常必要的。  相似文献   

3.
简要介绍了汶川地震震害和发震原因,根据汶川地震及其他地震灾害的经验,对汶川地震灾后重建中存在的一些工程地震问题进行了分析,对工程抗震设防的对策进行了探讨,以加强和重视建设工程抗震设防工作,提高工程结构防震抗震能力,为灾后重建提供有益参考价值.  相似文献   

4.
通过对庐江县民众防震减灾意识调查和分析,结果表明:(1)区域内少震,地震灾害关注度低,民众文化素质水平低,地震知识了解少,防震减灾意识淡薄;(2)民众对影响地震灾害结果的深度知识掌握差,地震灾害感知能力弱;(3)民众防震减灾知识匮乏,自救互救技能掌握较差,防震减灾信心不足,防震减灾响应能力较低;(4)区域经济不发达,民众房屋建筑抗震性能设计普遍较低,防震减灾外部条件对民众防震减灾信心支撑不足。高地震灾害脆弱性与民众安全需求之间的矛盾是引发地震恐慌的主因。  相似文献   

5.
三、当前世界上抗御地震灾害的措施地震作为人类环境的一个重大问题,只要地球存在一天,就存在发生地震的危险性。人类虽无力抗拒地震,却有法抗御地震灾害,这是人类为了自身的生存和发展而进行的一场艰巨斗争。当前,世界上抗御地震灾害的措施主要有以下三个方面: (一)地震预报就实际情况来说,如何提高地震预报水平是非常紧迫的问题。地震预报有三个要素:震级、地点和时间。预报的成功可以大大减轻人员的伤亡和经济损失。  相似文献   

6.
2008年5月12日四川汶川发生8.0级大地震,造成了重大损失.本文试图通过介绍地震的地质构造与深部地球物理场特征及现场考察、调研、交流、分析来寻找减轻地震灾害的有效办法.  相似文献   

7.
提出温差电场对岩石板块的弯曲效应及其他条件共同作用引发地震的理论。并用多种方法作为证明。提出地深型弱温差电场与全球每年约500万次无感弱地震的关系,岩浆型强温差电场的形成与平均全球每年不到二十次灾害性大地震及其"余震"的关系和原理。运用引发地震的原理提出判断无地震地区和有大地震发生的地区的根据和方法,并圆满地解释了地震相关的所有现象。提出预报大地震的两个可观测的重要征兆,并作为震前预报的根据和可靠方法。  相似文献   

8.
2018年云南多地遭受不同程度的风雹、洪涝、滑坡泥石流和地震灾害,先后发生了通海2次5.0级地震、麻栗坡"9·02"洪涝灾害、墨江5.9级地震、金沙江干流白格堰塞湖灾害等。全年呈现出中强度地震活动水平明显增强、洪涝和地质灾害频发至部分地区人员伤亡较重、金沙江干流堰塞湖灾害损失严重、低温冷冻和雪灾灾害损失突出等特点。综合描述了2018年云南主要自然灾害灾情,分灾种对发生特点及原因进行了初步分析,并给出了未来综合减灾对策及建议。  相似文献   

9.
对四川汶川大地震灾害的思考与认识   总被引:2,自引:0,他引:2  
2008年5月12日14时28分,我国四川省汶川发生8.0级大地震,造成重大伤亡和损失,灾区面积达10万平方公里.这是几十年来最大的地震灾害.作为地学的科技人员,对这么大的地震灾害未能有所预报更感到悲痛.虽然,由于地震是极其复杂的问题,在国内外目前还都是难题,但是如何减少损失,能够尽量达到临震预警和有科学的减灾预案,还是需要今后予以解决的问题.  相似文献   

10.
我国大多数破坏性地震发生在农村地区,据统计,1992~2005年14年间云南省发生的56次5.0级以上地震,有53次地震的震中位于农村地区,即95%的地震极灾区分布在农村地区.本文阐述了地震灾害对农村地区的影响,分析了农村地区成灾的原因,提出了地震灾害的防御对策和建议.  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

13.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

14.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

15.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

16.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

17.
以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.  相似文献   

18.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

19.
Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.  相似文献   

20.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

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