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1.
The heavy floods in the Taihu Basin Showed increasing trend in recent years.In this work,a typical area in the northern Taihu Basin was selected for flood rish analysis and potential flood losses assessment.human activities have strong impact on the study area‘s flood situation(as affected by the polders built,deforestation,population increase,urbanization,etc.) and have made water level higher,flood duration shorter,and flood peaks sharper.Five years of different flood return periods[(1970),5(1962),10(1987),20(1954),50(1991)] were used to calculate the potential flood risk area and its losses.The potential flood risk map,economic losses,and flood-impacted population were also calculated.The study‘s main conclusions are:1) Human activities have strongly changed the natural flood situation in the study area,increasing runoff and flooding;2) The flood risk area is closely related with the precipitation center;3) Polder construction has successfully protected land from flood.Shortened the flood duration,and elevated water leel in rivers outside the polders;4) Economic and social development have caused flood losses to increase in recent years.  相似文献   

2.
THE APPLICABILITY OF RESEARCH ON FLOOD-DROUGHT TENDENCY-AN ANALYSIS ON DISASTROUS FLOOD OF TAIHU LAKE BASININ JUNE-JULY,1991 ...  相似文献   

3.
In Taihu Lake basin during June–July in 1991, there happened a catastrophic flood, the precipitation reached that of 1954 and the water level was the highest in the history in Taihu Lake. This heavy flood, happening in the relatively humid period and being well accord with flood-drought change tendency, was early precautioned. The occurrence of the flood illustrated that using records of historical climate to predict flood-drough tendency is practically significant for hazard-reduction project.  相似文献   

4.
“从控制洪水向洪水管理转变”是我国当今治水和防洪方略调整的重要标志与必然趋向,对于如何实现从“控制洪水”向“洪水管理转变”,本文从电子政务系统的理念出发,探讨和分析了电子政务系统在洪水管理中的应用及其建设策略。  相似文献   

5.
随着计算机信息技术在水利学科中应用的深入,以及数字水利、数字流域概念的提出,水利信息化已经成为这一行业领域的主要发展方向,各种流域模型在与地理信息系统平台结合后在数据的收集、存储,提取与处理的基础上都有了很大的发展,在水利工程的规划设计、防洪减灾、水量分配等方面有更为广泛的应用。青岛市大沽河流域内洪水有来势猛、峰高量大和暴涨暴落的特性,为满足防汛管理部门对洪水预测及相关信息快速浏览查询的需求,建立了青岛市大沽河流域防汛信息系统。该系统在MAPX地理信息系统开发软件、数据库存储技术和水流数学模型的支持下,实现了大沽河流域的地理信息、水文信息以及其他信息的综合管理,同时通过水流数学模型对一维和二维洪水进行预测预报,并根据用户的需要完成所需的查询与分析功能,以最直观简洁的方式向用户展示系统的输出结果。系统数据库的开发在满足系统要求的基础上完成了与青岛市雨情水情自动监测系统的对接,保证了水文数据的实时性、完整性和准确性。系统集成了一维非恒定流模型与平面二维非恒定流水流模型,可以根据大沽河流域降雨量计算干流的水位变化以及发生溃堤后洪水的淹没过程。应用表明,该系统界面友好、功能完善、性能良好,具有很强的实用性。  相似文献   

6.
利用依兰-伊通断裂带北部地区1977年、1991年和2015年3期精密水准数据,采取伪逆基准下的线性动态运动模型进行平差,并归算到选取的基准点,分别获取该区域2期相对速率场(1977~1991年和1991~2015年)。前一期速率场表明,大致以依兰-伊通断裂带为界,该区域长白山北部相对于小兴安岭南段隆升,最大相对速率为7.51 mm/a;后一期速率场表明,整个依兰-伊通断裂带北部地区相对速率较小,最大相对速率仅为3.4 mm/a,该区域趋向于整体性的继承性运动,断裂带两侧相对运动明显减弱。  相似文献   

7.
During late February to mid-March, 1991, when mature N. japonica swarmed in the sea surface off Jimo County, Qingdao, seawater containing numerous early embryos was pumped into a nearby 2.7 ha. muddy-sand shrimp pond, where the embryos continued to develop. 800000 Penaeus chinensis seedlings were introduced into the pond on May 30, 1991. Monthly benthic samplings were carried out to determine the population dynamics and production of N. japonica in this atypical environ -ment.The density of N. japonica varied from 0 to 20400 ind./m2. The predation of P. chinensis was considered to be responsible for the mass mortality of N. japonica in June through July, when the worms were 2.2-3.3cm in length and lived in the top 2-4cm sediment. From August to September of 1991, the hottest period in the site, there was no substantial mortality of N. japonica as reported in earlier literature. This was explained by the deeper burrowing of the' worms that protected them from predation by shrimps.Monthly biomass ranged f  相似文献   

8.
Flashfloodsaretheimportanteventsofthehydrologicalregimeofriversinaridareas.IntheTarilncaver(Fig.1),northwesternChina,flashfledarebeingmonitored.TheobSerVeddataandinvestigationdemonstratethedifferenceintime,place,frequencyandintensityoftheiroccurrences.Therearethreet~offlagescommontotheThermcaverbasin.AlmOSteveryyea-rhighwateroccursinmonthesofJuly,AugUstandseptembercausedbyablationrunoff.However,themostdamagingflowSarefromoccasionalflashfindsbyinstenserainstormandglacierlakeoutburstflags(…  相似文献   

9.
开展Sentinel-1A SAR数据在洪水淹没范围提取和水体变化监测方面的应用研究,对科学有效地管理洪涝灾害有重要意义。合成孔径雷达以其不受天气影响、能穿透云层、覆盖面积广等特点成为灾害监测的重要数据来源。面向对象的方法能有效解决影像的椒盐现象被广泛运用于信息提取研究。本文基于Sentinel-1A SAR数据,利用面向对象的方法构建洪水淹没范围提取流程,绘制灾前、灾中、灾后水体变化监测图,对比分析基于传统像元的提取方法,实现对广西临桂会仙岩溶湿地区域不同时期洪水动态监测。研究表明,Sentinel-1A SAR数据在洪水监测领域有巨大的应用潜力,相较于传统基于像元的方法,面向对象的方法能有效抑制杂斑生成,提高空间信息的利用效率,具有更好的提取精度。  相似文献   

10.
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   

11.
Based on experimental data and theory, by means of simplified discharge durations in a small flume,the influence of discharge process on channel morphology and channel pattern was analyzed in this paper. It was concluded that on the same original channel, different discharge and channel conditions would end with different river morphology, including thalwegs and radius of bends. Different discharge process resulted in two kinds of change:tiny change in the process of “big-small-big” and distinct change in the process of “small-big-small”. Flood discharge duration was verified to be the main cause in the discharge process. Proper discharge process will change the morphologies of river, even can led to channel pattern transformation. The influences based on the relationship between the flow and the channel itself, including slope and riverbed constitution. Although not be a main cause, original channel morphology may influence its final channel pattern. Neglecting the influence of channel itself will hamper the understanding of channel patterns.  相似文献   

12.
全国山洪灾害调查评价成果及规律初探   总被引:2,自引:0,他引:2  
山洪灾害调查评价是1949年来水利行业最大的非工程措施项目,是规模最大的全国性防灾减灾基础信息普查工程,历时4年,涉及全国30个省305个市2138个防治县(区),国土面积755万km2,人口近9亿。运用普查、详查、外业测量、分析计算等多种手段,掌握了中国山洪灾害防治区范围、人员分布、下垫面条件、社会经济、历史山洪灾害等基本情况,科学分析了山丘区小流域的暴雨洪水特性,评价了现状防洪能力,计算了预警指标,划定了危险区,为山洪灾害预警预报和应急救援决策提供了基础信息支撑。本文系统介绍了全国山洪灾害调查评价的核心要点,综述了调查评价成果,归纳了调查评价成果要素类型,揭示了全国山洪灾害防治区、人口、历史山洪灾害事件与预警能力的空间分布一致性,即山洪灾害各要素集中分布于青藏高原-四川盆地过渡带、川滇交界地区、黄土高原区、东部沿海地区及华北等地区,最后初步探讨了该成果的应用前景。全国山洪灾害调查评价成果将为中国山洪灾害监测预警预报体系建设及防灾减灾能力提升提供丰富的基础数据支撑。  相似文献   

13.
基于洪峰模数的山洪灾害雨量预警指标研究   总被引:1,自引:0,他引:1  
山洪灾害预警是防御山洪的重要非工程措施,雨量预警指标是山洪灾害预警的关键。目前的雨量预警指标计算方法对水文气象资料条件以及模型建模率定都有很高的要求,并不适用于基层防汛人员。因此,本文基于全国山洪灾害调查评价成果数据,提出了一种运用洪峰模数计算雨量预警指标的简便、易用的方法。该方法以小流域洪水计算推理公式为基础,将公式中流量与流域面积的比值用洪峰模数表示,得到基于洪峰模数的临界雨量估算公式,并考虑流域土壤含水量等因素,分析临界雨量变化阈值,最终得到雨量预警指标。本文以云南省绥江县双河小流域为例,计算结果显示不同时段(1 h、3 h、6 h)净雨量和预警时段呈线性关系。降雨损失计算中洼地蓄水和植被截留在不同时段相同,土壤下渗在不同的时段不相同。在此基础上,计算不同土壤含水量条件下,不同时段的雨量预警指标。最后,对临界流量、降雨损失和预警指标进行了合理性分析,结果显示预警指标和调查评价结果及实测降雨都比较接近,计算的预警指标合理。本研究为基层山洪灾害预警提供了一种快速、便捷的预警指标计算方法,为预警指标计算提供技术支持。  相似文献   

14.
VR-GIS技术在城市“数字防洪”中的应用   总被引:7,自引:1,他引:6  
虚拟现实地理信息系统(VR-GIS)是一门综合虚拟现实和地理信息系统特征的新型技术,以此为基础构建的城市数字防洪系统在防洪决策中发挥了积极的辅助作用。本文以哈尔滨城区段三维数字防洪系统的开发为背景,探讨了VR-GIS应用于城市数字防洪的关键技术及其实现方法,包括防洪三维虚拟场景的构建技术,仿真数据库的建立与联合查询,洪水动态模拟等方面的相关技术和实现方法,为数字防洪系统提供了基础研究平台。  相似文献   

15.
应用灰色系统理论的GM模型对短边测距资料进行了处理并识别异常,发现在绝大多数中强地震前,如1989年大同6.1级地震,1991年大同5.8级地震,1991年唐山4.8级、5.1级地震,1995年唐山古冶5.0级地震,1996年包头6.4级地震,1998年张北6.2级地震前,均有比较明显的异常显示.对所建模型的精度进行了检验,证明这一方法识别异常可靠,可用于地震预报.  相似文献   

16.
In this paper, we investigated the potential of Advanced Microwave Scanning Radiometer for Earth Observation System (AMSR-E) for flood monitoring. The proposed approach was based on the polarized ratio index (PRI), which was computed by using AMSR-E data at 37GHz, vertically and horizontally polarized brightness temperature values and the water surface fraction (WSF) got by using the PRI at 37GHz. Moderate Resolution Imaging Spectroradiometer (MODIS) data were used to validate the WSF values. The analysis of flood and waterlogging using the WSF map on July 6, 2003 indicates that the use of WSF for flood and waterlogging disaster assessment is feasible. Utilizing the correlation of WSF derived from AMSR-E and water area derived from MODIS, the water area of the Huaihe River Basin were computed by only using AMSR-E data in the summer of 2003, which overcame the influence of cloud on water estimation using MODIS data during flood.  相似文献   

17.
Land use and land cover changes that occurred during the period from 1991 to 2001 in the Jahlma watershed of the Lahaul valley, a cold desert region of the northwestern Himalaya, were evaluated using land use data and visual interpretation of IRS Satellite imageries. The results revealed that out of the six major land use forms within the watershed, land areas under agriculture, kitchen garden and settlement land were found increased, whereas a declining trend was recorded in areas under grassland, barren land and Salix plantation. The cultivated land within the watershed increased from 54.87 % (total of agriculture land, kitchen garden, grassland, barren land, Salix plantation and residential area) in 1991 to 56.89 % in 2OOl, corresponding to an expansion of 4.41 ha. On the other hand, the areas of grassland decreased from 31.41% in 1991 to 29.81% in 2001. Such a dramatic land use and land cover changes taking place within the 33 km^2 watershed area in a single decade deafly indicates the prevailing danger of land degradation and environmental deterioration in the region.  相似文献   

18.
In the fifth paper listed in the references, East China was divided into eight drought/ flood regions. But we, taking earth rotation velocity, sunspots, southern oscillation, etc. as the influence factors, through step-wise regression analysis and typical analysis, discussed drought/ flood influence factors of the eight regions. On the basis of them, applying spectrum analysis, we calculated the cycles of every influence factor variation and cycles of drought/ flood variations of every region as well as cycles of vibration between them. The results indicate that the drought/ flood influence factors of East China are southern oscillation, earth rotation velocity, etc. Specially, the influence of EL-Nino is more evident to drought/ flood in most regions than that of others. Generally, there are good correlations between the year of EL-Nino and the year of drought/ flood in most regions. The ways of these factors influencing drought/ flood are shown in lag correlation, by 2-5-year high-frequency vibration  相似文献   

19.
Located in the headwater upstream of the Taihu Lake region, which is a densely populated and economically developed area in China, the West Tiaoxi River catchment is a frequently food-hit area due to its nature and climatic characteristics. During the last several decades, more than ten catastrophic floods happened in this area, causing huge economic losses. Since 1990, due to the increasing property vulnerability to flood hazard, the disasters were even more serious than before, and economic losses increased year by year. Thus, there have great importance to study flood behaviors, flood risks and their consequences. In this paper the hydrologic/hydraulic modelling is presented firstly. It is the method to study the relationship between rainfall and runoff and the flood propagation process. Secondly, the author gives the summary of the current study methods for flood risk assessment. The West Tiaoxi River catchment has a long history of the construction of polders and hydraulic engineering. Most farmlands have been protected against floods. So the combination method has been used to obtain the real risk area. The results have been obtained by using this method, which, the authors think, will be used in disaster preparedness, property insurance etc. Foundation item: Under the auspices of the National Natural Science Foundation of China (No. 49671028) and Deutsche Forschungsgemeinschaft (DFG). Biography: XU Peng-zhu (1965 —), male, a native of Funing County of Jiangsu Province, associate researcher. His research interests include hydrology and water resources, numerical modelling, and application of GIS to hydrology.  相似文献   

20.
A fundamental element of sustainable development is that humans live within nature's biological capacity. Quantifying this, however, remains a significant challenge for which there are many emerging tools. The concept of the Ecological Footprint is one such accounting tool for comprehensive assessment of the status of sustainable development, based on integration of resource consumption and land capacity, reflecting the human impact on the environment. A region's development is defined as unsustainable when the Ecological Footprint surpasses the biological capacity. In this paper, the Ecological Footprint concept Was applied in assessing the development of Yunnan Province, China in a period between 1988 and 2006. The results showed that the Ecological Footprint per capita in Yunnan rose from 0.854 gha in 1988 to 2.11 gha in 2006. Ecological deficit, defined as when the human demand on the land surpasses the regions biological productive capacity, emerged in 1991 and quickly increased from 0.02 gha in 1991 to 1.05 gha in 2006. The increase in the ecological deficit is primarily a result of the rapid increase in population and consumption level. To achieve sustainable development in Yunnan, production and consumption rates need to be modified.  相似文献   

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