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1.
The Western Carpathians are located out of world main natural hazardous zones. Human casualties are related more to snow avalanches in connection with mountain hiking, some individuals yearly by flooding and rarely by forest fires. Economic lost about 0.1 to 0.2 %, exceptionally up to 0.8 % of the gross domestic product (GDP) proportionally to the Carpathian regions of particular countries. Natural disasters are linked, except of the above mentioned events, to infrequent small and medium scale earthquakes, landslides, and erosion. Records of the most harmful natural events are found in archives since the 16^th century. Their systematic study and factor analysis started from the end of the 19^th century, and protective measures and organization of impact mitigation developed during the 20^th century to minimize the risk.  相似文献   

2.
1 INTRODUCTION The Changjiang (Yangtze) Delta and its neighboring regions mentioned in this article is located in the lower reaches of the Changjiang River, whose north, east, south and west adjacent places are Xingtongyang Canal, Huanghai Sea, East China Sea, Qiantang River, Hangzhou Bay and Nanjing, Zhenjiang respectively. These regions belong to Jiangsu Province, Zhejiang Province and Shanghai City in administrative division, being one of the economic developed regions. The …  相似文献   

3.
DRY/WET CLIMATE CHANGE SINCE 960 A.D.IN TAIHU DRAINAGE BASIN OF CHINA   总被引:1,自引:0,他引:1  
IINTRODUCTION climate chang巳 divided d叮/wet penodS and discussed itsrelationships with cold/warm vanatlon and solar activityRecords ofellmate dlsasterhave been abundantly(CHEN198飞 1989).IOund In Chinese historical literature.Previous works The present study tends to establish the dry/wethave collected such records to study the historical elf-series since 960 A.D.ofTal…  相似文献   

4.
Lanzhou Valley Basin is composed of two smaller diamond-shaped basins striking from NW to SE and including 6 river terraces. The lower terraces remaining even and smooth are main sites for city buildings. The main function of Lanzhou urban settlement is a ferry and transport centre. Lanzhou used to be an important crossing site and post on the “silk road”, and then became a transport and trade centre in Northwest China. In the middle part of the 17th century, Lanzhou became the capital of Gansu, a new province. The development process of Lanzhou urban settlement indicates that urban settlement is a system consisting of natural environment and human society based on the former.  相似文献   

5.
针对天然地震事件、爆破事件分类问题,使用甘肃及周边地区80个天然地震事件和20个爆破事件建立数据集,采取深度学习卷积神经网络(convolutional neural network,CNN)方法搭建两个不同结构的模型进行训练,并用500条训练集之外的天然地震事件与爆破事件波形作为测试数据集,其训练和测试准确率均达到9...  相似文献   

6.
The purpose of this study is to investigate the control function and mechanisms of natural river notches. Physical and numerical experiments are analyzed in this study for two representative types of sediment events: high intensity and short duration Type A sediment disaster events, and low intensity and long duration Type B moderate non-disaster events. Two dimensionless parameters, sediment trapping rate and reduction rate of peak sediment transport, are defined to evaluate the sediment control function of river notches. Study results indicate that the contraction ratio of the notch has a significant influence on sediment control function, with high contraction ratios resulting in both high sediment-trapping and high reduction rates. River notches provide better sediment control during Type A events than Type B events. The sediment control mechanism of river notches is the result of multiple interactions among river flow, sediment transport, and riverbed variation. Analysis of these interactions supports the significant protection role of river notches on sediment control for disaster events  相似文献   

7.
文学思潮与民间文化都是具有特定内涵的严格概念,与其他思潮既有联系又有区别,民间文化因为自己特殊的存在状态和创造主体而形不成思潮,二十世纪中国文学发展中的五大运动都与民间文化有关,但是不能以民间文化思潮的面目出现。高有鹏先生的《论二十世纪中国文学发展中的民间文化思潮》命题不准确,文中尚有许多可以商榷之处。  相似文献   

8.
在中国十九世纪末二十世纪初的启蒙运动中,启蒙思想家们将启蒙国民性的重点放在了批判儒家思想中的家族制度和家族伦理上。家族制度和家族伦理作为封建父权的安身立命之所,对它们的质疑和瓦解必然导致父权在整体上被瓦解,从此,父权走上了衰微之路。  相似文献   

9.
本科院校办高职学院是我国 2 0世纪末出现的一个新生事物 ,如何设置专业课程 ,提高教学质量 ,使学生一出校门就能容纳到直接为经济服务当中去 ,结合商务日语专业的具体情况对这个问题进行了思考。  相似文献   

10.
On the basis of large amount of historical and measured data,this paper analyzed the regional,periodic,frequency,continuing,and response characteristics of droughts and floods in Zhejiang and proposed the conception of ratio of peak runoff.Main characteristics of droughts and floods in Zhejiang are as follows:1)The western Zhejiang region is plum rain major control area,and the eastern coastal region of Zhejiang is typhoon major control area.2)Within a long period in the future,Zhejiang will be in the long period that features droughts.3)In Zhejiang the 17th century was frequent drought and flood period,the 16th,19th,and 20th centuries were normal periods,while the 18th century was spasmodic drought and flood period.4)The severe and medium floods in Zhejiang were all centered around the M-or m-year of the 11-year sunspot activity period.5)There are biggish years of annual runoff occurred in El Ni?o year(E)or the following year(E 1)in Zhejiang.The near future evolution trend of droughts and floods in Zhejiang is as follows:1)Within a relatively long period in the future,Zhejiang Province will be in the long period of mostly drought years.2)Between 1999 and 2009 this area will feature drought years mainly,while the period of 2010-2020 will feature flood years mostly.3)Zhejiang has a good response to the sunspot activities,and the years around 2009,2015,and 2020 must be given due attention,especially around 2020 there might be an extremely severe flood year in Zhejiang.4)Floods in Zhejiang have good response to El Ni?o events,in El Ni?o year or the following year much attention must be paid to.And 5)In the future,the first,second,and third severe typhoon years in Zhejiang will be 2009,2012,and 2015,respectively.  相似文献   

11.
Lanzhou Valley Basin is composed of two smaller diamond-shaped basins striking from NW to SE and including 6 river terraces. The lower terraces remaining even and smooth are main sites for city buildings. The main function of Lanzhou urban settlement is a ferry and transport centre. Lanzhou used to be an im-portant crossing site and post on the "silk road",and then became a transport and trade centre in Northwest China. In the middle part of the 17th century, Lanzhou became the capital of Gansu,a new province. The development process of Lanzhou urban settlement indicates that urban settlement is a system consisting of natural environment and human society based on the former.  相似文献   

12.
郑和作为 15世纪世界航海事业的启幕人 ,其航海壮举标志着中国海洋文化发展到中国历史的一个颠峰。之后 ,西方海洋文化的发展 ,成为欧洲资本主义工业化的历史前奏。中国海洋文化的衰弱 ,为近代中国历史定势埋下伏笔。 15世纪前后 ,中西海洋文化的生存价值取向、经济价值取向和人文价值取向具有不同的特征 ,这使得一直雄踞人类海洋文化前列的中国海洋文化 ,最后被西方海洋文化取代。  相似文献   

13.
Deyeuxia angustifolia wetlands were widely distributed in the Sanjiang Plain in Northeast China. Due to strong demand for food production, large-area wetlands were reclaimed to farmlands, which threatened regional ecological security greatly. Since the 21 th century, returning farmlands to wetlands was widely adopted for natural restoration in the Sangjiang Plain. As the first reflection of wetland restoration, vegetation succession of restored D. angustifolia wetlands should be fully assessed. In this study, vegetation investigation was carried out in three restored D. angustifolia wetlands with 5, 8 and 12 yr restoration, respectively. Meanwhile, a natural D. angustifolia wetland was selected as reference wetland. Results showed that community composition changed greatly and there was visible community succession. Community dominant species changed from composite to gramineae as restoration time increasing.At first, weeds community appeared in the restored wetlands, especially the xerophytes developed to the pioneer species rapidly. And then, mesophytes and wetland species became the dominant species in the restored wetlands. Finally, wetland species, especially D. angustifolia, occupied the dominant position of restored community. Shannon-wiener index(H) and Simpson index(D) both decreased to close to natural D. angustifolia wetlands. Compared with natural D. angustifolia wetland, species composition and diversity in restored wetlands were more complex and higher. As restoration time increasing, there were not significant differences between community characteristics of restored wetlands and natural wetland. All these suggested that vegetation in reclaimed D. angustifolia wetland could be restored naturally, but its restored period is 10 yr at least. From another angle, it is important to protect current natural wetlands.  相似文献   

14.
Natural gas hydrates are considered as strategic resources with commercial potential in the 21st century. Obvious BSR characteristics will be shown on seismic profiles, if there exist natural gas hydrates. The AVO method is one of the methods which can be used to identify and forecast lithologic characteristics and fluid properties by using the relationship between Amplitude and Offset. AVO anomaly is one of the significant signs to check out whether or not there is free gas below the BSR, so it can be used to detect natural gas hydrates from the seismic profile. Considering the geological and geophysical characteristics of the Okinawa Trough and making use of the techniques mentioned above, we can conclude that the conditions there are favorable for the formation and concentration of natural gas hydrates. By analyzing the data collected from the study area, one can discover many different anomalous phenomena on the seismic profile which are related to the existence of natural gas hydrates. Preliminary estimation of the natural gas hydrates in the Okinawa Trough shows that the trough is rich in natural gas hydrates and may become a potential important resources exploration area.  相似文献   

15.
20世纪70年代由于防洪、防凌的需要,黄河两侧修建了南、北展宽区,受防洪的限制,展宽区内群众的经济发展相对落后。小浪底水库建成运用后,南北展宽区失去其防洪作用,该文分析了南北展宽区内经济现状和资源的优劣势,针对如何利用现有条件就资源开发、优势互补等方面提出了设想和建议。  相似文献   

16.
电气石因其特殊的物理性质而被国内外学者广泛关注,并形成了大量的研究成果和应用专利。目前国内外对电气石的研究主要集中在晶体矿物学、找矿矿物学和岩石矿物学、晶体物理化学特性、矿床资源特征4个方面。自20世纪40年代以来,围绕电气石的晶体结构和电气石物理特性的内在动因等,中外学者做了大量深入细致的基础研究,并在利用电气石的化学成分判断成矿、成岩地质环境方面取得了许多宝贵的经验。近几年,国内外利用电气石的物理特性制造环保、保健产品等获得突破,展现了电气石的良好开发前景。  相似文献   

17.
王敏  张尚坤  赵鹏大 《山东国土资源》2007,23(6):2006/12/26-2007/4/13
电气石因其特殊的物理性质而被国内外学者广泛关注,并形成了大量的研究成果和应用专利。目前国内外对电气石的研究主要集中在晶体矿物学、找矿矿物学和岩石矿物学、晶体物理化学特性、矿床资源特征4个方面。自20世纪40年代以来,围绕电气石的晶体结构和电气石物理特性的内在动因等,中外学者做了大量深入细致的基础研究,并在利用电气石的化学成分判断成矿、成岩地质环境方面取得了许多宝贵的经验。近几年,国内外利用电气石的物理特性制造环保、保健产品等获得突破,展现了电气石的良好开发前景。  相似文献   

18.
中国浪漫主义文学的发展源远流长,从楚汉浪漫传统到晚明叛逆洪流,中国古代浪漫主义文学由幼稚走向成熟,也逐渐产生了和现代浪漫思潮相同的精神内涵,这就是强烈的自我意识和反叛意识;20世纪"五四"时期,在新文化运动的背景上发展出全新的、更为自由奔放的、波澜壮阔的现代浪漫主义文学巅峰。由于政治环境、文化氛围、文学传统等多种因素的影响,中国古代浪漫主义文学在广度、深度等方面都与现代浪漫主义文学存在明显差异。  相似文献   

19.
采用gCAP方法反演2010~2019年山西地区87次天然地震、18次塌陷及9次爆破的全矩张量解。结果显示,gCAP方法在反演山西地区震源机制方面效果较好。2016-03-12山西盐湖ML4.8地震的断层错动方式为走滑兼正断,全矩张量解中包含非双力偶成分,属于体积缩小的内向闭合型破裂。对于山西地区的地震事件,可将全矩张量解中双力偶分量占比是否大于80%作为判别天然地震及非天然地震的依据。对于非天然地震事件,当参数ζ>0时为外向爆炸源,反之为内向闭合源。  相似文献   

20.
21世纪世界的资源和环境   总被引:2,自引:0,他引:2  
20世纪世界人口从15亿增长到60亿.而经济成长更为快速,自1950年至今已增长4倍.目前世界人口每年增加8000余万人,至2050年将达到90亿,世界经济是否能持续发展以提升或维持现有的生活水准,值得研讨.资源的消长和环境的变迁是具有决定性的两大重要议题.  相似文献   

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