济南市南部山区小流域景观格局分析   总被引：4，自引：0，他引：4  

秦艳红  王立红  赵红兵 《山地学报》2003,21(5):576-581

根据2000年spot影像资料，应用地理信息系统软件ARC／INFO进行解译，并参照地形图、土地利用图等图件得到研究区景观类型图。应用景观生态学的方法，对各流域的景观格局分别进行定量计算，并进行比较研究。研究表明，各流域优势景观各有不同，从锦阳川至锦绣川、锦云川，景观多样性程度降低，优势度升高，林地破碎化程度增强，从而导致水土流失程度加深，人文因素是导致景观格局空间差异的主导因素。  相似文献   

2001年全世界灾害性地震综述   总被引：2，自引：0，他引：2  

李卫平  赵荣国 《国际地震动态》2002,(3):15-18

2001年全世界地震活动水平属于中等偏高,地震灾情比往年较重。地震死亡人数总计17 770人,伤15 9370人,经济损失约77亿美元。2001年印度是地震灾害最严重的国家。  相似文献   

Seismic Hazard and Loss Estimation for Central America   总被引：2，自引：2，他引：2  

Yong  Chen  Ling  Chen  Güendel  Federico  Kulhánek  Ota  Juan  Li 《Natural Hazards》2002,25(2):161-175

A new methodology of seismic hazard and loss estimation has been proposed by Chen et al. (Chen et al., 1998; Chan et al., 1998) for the study of global seismic risk. Due to its high adaptability for regions of different features and scales, the methodology was applied to Central America. Seismic hazard maps in terms of both macro-seismic intensity and peak ground acceleration (PGA) at 10% probability of exceedance in 50 years are provided. The maps are all based on the global instrumental as well as historical seismic catalogs and available attenuation relations. Employing the population-weighted gross domestic product (GDP) data, the expected earthquake loss in 50 years for Central America is also estimated at a 5' latitude × 5' longitude resolution. Besides the seismic risk index, a measure of the relative loss or risk degree is calculated for each individual country within the study area. The risk index may provide a useful tool to help allocations of limited mitigation resources and efforts for the purpose of reduction of seismic disasters. For expected heavy loss locations, such as the Central American capital cities, earthquake scenario analysis is helpful in providing a quick overview of loss distribution assuming a major event occurs there. Examples of scenario analysis are given for San Jose, capital of Costa Rica, and Panama City, capital of Panama, respectively.  相似文献   

Characteristics of low frequency oscillations of the atmosphere-ocean coupling     

Randhir Singh  B. Simon  P. C. Joshi 《Journal of Earth System Science》2002,111(4):413-423

The low frequency oscillation of latent heat flux over the tropical oceans has been studied. The NCEP reanalyzed fields of wind and humidity alongwith Reynolds SST are used to compute the instantaneous as well as monthly mean surface latent heat fluxes (LHF) for the year 1999. The procedure of LHF computation is based on bulk method. Spectral analysis shows that significant energy is contained in Madden Julian Oscillation band in the winds, SST, moisture and in the latent heat flux. The global distribution of wind, humidity, SST and LHF oscillation on the time scale of 30–50 days are analyzed. Maximum amplitude of oscillation on this time scale in all the above mentioned parameters were found over the Indian Ocean. The fluctuation of surface wind speed and moisture controls the latent heat flux on this time scale. The fluctuation of SST on this time scale does not seem to be important over most of the oceans.  相似文献   

Nutrient Loss from Various Land－Use Areas in Shixia Small Watershed of Miyun County,Beijing China   总被引：1，自引：0，他引：1  

王晓燕  王晓峰  王振刚  汪青平  蔡新广 《中国地球化学学报》2003,22(2):173-178

In the Shixia small watershed,twenty experimental plots and two monitoring channels,the residential area and livestock areas were used to monitor the flow,runoff and erosion,Nitrogen and phosphorous concentrations associated with various land uses were analyzed at the same time.The results are presented as follows:(1)TP ,TN and COD concentrations of runoff samples in the residential area and livestock arease are nearly 10 times those in other land-use areas.High nutrient loads are associated with village land use,which is due to unsuitable livestock rising.These areas should be treated as the critical areas of non-point source pollution.(2)Different land use influences intensity the loss nutrients,especially slope tillings in agricultural land.The amount of nutrient loss from agricultural land per unit is highest,that from forestry is intermediated and that frompastures is lowest,However,in consideration of the variability of land-use areas,agricultural land contributes the greatest to TP and forestry land to TN.(3)The concentrations of TN and TP in sediments from gangues are highest ,those in forestry land are intermediate,and those in agricultural land are lowest.Nutrient loss from hilly areas in much greater than from mountainous areas.  相似文献   

Study on evaluation of cities’ ability reducing earthquake disasters     

Zhang Feng-hua  Xie Li-li  Fan Li-chu 《地震学报(英文版)》2004,17(3):349-361

Cities’ ability reducing earthquake disasters is a complex system involving numerous factors, moreover the research on evaluating cities’ ability reducing earthquake disasters relates to multi-subject, such as earthquake science, social science, economical science and so on. In this paper, firstly, the conception of cities’ ability reducing earthquake disasters is presented, and the ability could be evaluated with three basic elements — the possible seismic casualty and economic loss during the future earthquakes that are likely to occur in the city and its surroundings and time required for recovery after earthquake; based upon these three basic elements, a framework, which consists of six main components, for evaluating city’s ability reducing earthquake disasters is proposed; then the statistical relations between the index system and the ratio of seismic casualty, the ratio of economic loss and recovery time are gained utilizing the cities’ prediction results of earthquake disasters which were made during the ninth five-year plan; at last, the method defining the comprehensive index of cities’ ability reducing earthquake disasters is presented. Thus the relatively comprehensive theory frame is set up. The frame can evaluate cities’ ability reducing earthquake disasters absolutely and quantitatively and consequently instruct the decision-making on reducing cities’ earthquake disasters loss. Foundation item: State Important Research Project of China (95130603).  相似文献   

中国自然灾害保险风险度综合评判与区划   总被引：11，自引：1，他引：11  

刘丽  代宏霞 《山地学报》2004,22(4):477-482

首先将自然灾害保险风险评判分为灾害危险性与灾害易损性评判，以省、市、自治区划分自然灾害保险风险区，选择地质、地震、洪水、台风等四种自然灾害进行了自然灾害综合危险性评判；再将自然灾害易损性评判分为两个层次，第一层次是经济易损性与社会易损性评判，以风险区国内生产总值和固定资产投资作为评判指标进行了自然灾害经济易损性评判，以风险区人口密度作为指标进行了社会易损性评判，在此基础上进行了第二层次——自然灾害易损性评判；然后以自然灾害综合危险度和易损度指标值作为评判因子进行了自然灾害保险风险度综合评判；最后根据评判结果得到了各风险区的自然灾害保险风险度，由此绘制了中国自然灾害保险风险区划图。  相似文献   

2003年陕西秋季连阴雨降水特点及环流条件分析   总被引：24，自引：0，他引：24       下载免费PDF全文

方建刚  白爱娟  陶建玲  高炬 《应用气象学报》2005,16(4):509-517

文章分析了陕西省2003年秋季连阴雨降水的特征和形成秋季连阴雨天气的天气学、热力学特点。结果表明:2003年陕西秋季连阴雨降水的主要特征是降水的落区和时间相对集中, 降水强度大, 日数多且持续时间长, 是1954年以来陕西又一次极端连阴雨事件。在大气环流由夏季型向冬季型转变过程中, 对流层高层西风急流南压至40°N时, 青藏高原东北侧包括陕西在内的西北地区东部, 位于急流南侧的高空辐散区, 该地区对流层低层却保持着高温高湿的热力特征, 对流上升运动活跃, 形成了低层辐合高层辐散的垂直环流机制, 这时对流层中部500 hPa欧亚环流形势相对稳定, 乌拉尔山的长波脊和中亚低槽维持, 偏强、偏北、偏西的副热带高压外围偏南气流为该区域输送了大量的水汽, 从而形成了陕西及西北地区东部持续的连阴雨天气; 当西风带中纬度新疆高压脊建立, 副热带高压东移南退时, 陕西及西北地区东部的连阴雨天气结束。  相似文献   

Estimating Injury and Loss of Life in Floods: A Deterministic Framework   总被引：3，自引：3，他引：3  

Edmund Penning-Rowsell  Peter Floyd  David Ramsbottom  Suresh Surendran 《Natural Hazards》2005,36(1-2):43-64

This paper presents an outline methodology and an operational framework for assessing and mapping the risk of death or serious harm to people from flooding, covering death and physical injuries as a direct and immediate consequence of deep and/or fast flowing floodwaters (usually by drowning), and deaths and physical injuries associated with the flood event (but occurring in the immediate aftermath). The main factors that affect death or injury to people during floods include flow velocity, flow depth, and the degree to which people are exposed to the flood. The exposure potential is related to such factors as the “suddenness” of flooding (and amount of flood warning), the extent of the floodplain, people’s location on the floodplain, and the character of their accommodation. In addition, risks to people are affected by social factors including their vulnerability and behaviour. A methodology is described for estimating the likely annual number of deaths/injuries. This is based on defining zones of different flood hazard and, for each zone, estimating the total number of people located there, the proportion that are likely to be exposed to a flood, and the proportion of those exposed who are likely to be injured or killed during a flood event. The results for each zone are combined to give an overall risk for each flood cell and/or community. The objective of the research reported here is to develop a method which could be applied using a map-based approach in which flood risks to people are calculated and displayed spatially for selected areas or communities. The information needed for each part of the process is described in the paper, and the further research to provide the required information is identified.  相似文献   

Study on evaluation of cities ability reduc-ing earthquake disasters     

张风华  谢礼立  范立础 《地震学报(英文版)》2004,17(3)

Introduction At the end of last century, the Committee of International Decade for Natural Disaster Re-duction had called on evaluating the ability reducing earthquake disasters of cities. However, since efficient method to assess earthquake loss of cities does not exist, the proposition did not come true. In 1994, China government put forward that the cities with dense population or developed economy and the areas off the seashore should have the ability to resist earthquake (M=6). Un-dou…  相似文献