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1.
辽西北地区农业干旱灾害风险评价与风险区划研究 总被引：5，自引：0，他引：5
以辽西北29个农业县（市、区）为研究区域,选取辽西北最主要的玉米作物作为研究对象,从造成农业干旱灾害的致灾因子危险性、承灾体暴露性、脆弱性和抗旱减灾能力4个方面着手,利用自然灾害风险指数法、加权综合评价法和层次分析法,建立了农业干旱灾害风险指数（ADRI）,用以表征农业干旱灾害风险程度;借助GIS技术,绘制辽西北农业干旱灾害风险评价区划图,将风险评价区划图与2006年辽西北受干旱影响粮食减产系数区划图对比,发现两者可以较好的匹配。研究结果可为当地农业干旱灾害预警、保险,以及有关部门的旱灾管理、减灾决策制定提供理论依据和指导。 相似文献
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Disaster risk evolves spatially and temporally due to the combined dynamics of hazards, exposure and vulnerability. However, most previous risk assessments of natural disasters were static and typically based on historical disaster events. Dynamic risk assessments are required to effectively reduce risks and prevent future losses. Based on rainstorm disaster data and meteorological information collected in Dalian, China, from 1976 to 2015, the hidden Markov model (HMM) was used to detect inter-annual changes in rainstorm disaster risks. An independent sample test was conducted to assess the reliability of the HMM in dynamic risk assessments. The dynamic rainstorm risk in Dalian was simulated based on the observation probability matrix, which characterized the relationship dependence between rainstorm hazard and risk, and the probability matrix of state transition, which reflected the probability of changes for the risk level. High rainstorm risk was associated with high-hazard rainstorms and continuously appeared with little probability in several successive years. The reliability applied the HMM to simulate the rainstorm disaster risk was approximately 67% in the dynamic risk assessment. Additionally, the rainstorm disaster risk in Dalian is predicted to be at a medium-risk level in 2017, with a probability of 0.685. Our findings suggest that the HMM can be effectively used in the dynamic risk assessment of natural disasters. Notably, future risk levels can be predicted using the current hazard level and the HMM. 相似文献
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承灾体脆弱性评估是科学进行灾害风险评估和预测的基础，房屋建筑作为面大量广的承灾体，众多学者对建筑物理脆弱性指标模型进行了研究。基于单灾种和多灾种2个维度，针对指标模型构建的各环节，全面梳理了几种典型单灾种物理脆弱性指标体系和评估模型构建情况，发现指标选取理论依据不明确，模型构建主观性较强，不能准确表征建筑特点与抗灾能力间的内在联系。系统总结了多灾种指标体系和耦合物理脆弱性指标模型研究现状，发现多灾种之间及其对承灾体影响的复杂耦合效应在现有指标模型中未得到充分体现。研究结果表明，明晰指标依据、优化模型构建是提升单灾种物理脆弱性评估准确性的关键；改进脆弱性耦合模型、拓展综合脆弱性评估方法是健全多灾种脆弱性评估研究的核心。 相似文献
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东南沿海水库下游地区基于动态模拟的洪涝风险评估 总被引：1，自引：1，他引：0
我国东南沿海地区大多为一些中小流域,这些流域上游多建有水库工程,下游则为人口稠密的平原区,流域调蓄能力小,汇流时间短.同时,随着近年来城镇化快速发展,洪涝风险不断加大.因此,迫切需要开展水库下游不同暴雨重现期下的洪涝风险评估研究,以便为防洪决策提供技术支撑.为此,本文利用遥感、GIS、水文水动力学模型等相关技术方法,建立洪涝动态模拟模型来评估洪涝危险性;采用层次分析法和因子叠加法,从洪涝危险性和洪涝易损性两方面开展洪涝风险综合评估分析.研究表明,通过多学科与多技术手段相结合方法,来模拟预测不同暴雨重现期洪水动态淹没过程,再结合相关社会经济属性,可以有效地评估研究区洪涝灾害的风险,从而为水库调度及流域防洪减灾提供有力支撑. 相似文献
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洪水风险=灾害事件×暴露程度×脆弱程度 总被引：2，自引：0，他引：2
Wolfgang KRON 《湖泊科学》2003,15(Z1):190-204
世界上,洪水可能是造成损失最大的自然灾害.世界上没有哪个地区不受到洪水的威助、由于洪灾风险是灾害事件、洪泛区财产遭遇风险的程度,以及它们的脆弱性的函数,所以灾害损失的增长与上述各个方面的变化都有关.防洪措施可以减少灾害事件的频率,恰当的预防措施也能显著降低财产风险.然而除了公共措施和私人措施外,在减少私人、企业、甚至整个社会的风险方面,保险发挥着关键作用.近年来,对洪水保险的需求日益增长,促使保险公司必须采取适当的解决方案.与此同时,至关重要的是,保险公司应当清楚在极端情况下他们自己可能承担的最大损失. 相似文献
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Dynamic risk assessment model for flood disaster on a projection pursuit cluster and its application 总被引：2，自引：1，他引：1
Jun Zhao Juliang Jin Qizhong Guo Li Liu Yaqian Chen Mei Pan 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(8):2175-2183
Aiming at reducing the losses from flood disaster, a dynamic risk assessment model for flood disaster is studied in this article. This model is built upon the projection pursuit cluster principle and risk indexes in the system, proceeding from the whole structure to its component parts. In this study, a fuzzy analytic hierarchy approach is employed to screen out the index system and determine the index weight, while the future value of each index is simulated by an improved back-propagation neural network algorithm. The proposed model adopts a dynamic evaluation method to analyze temporal data and assesses risk development by comprehensive analysis. The projection pursuit theory is used for clustering spatial data. The optimal projection vector is applied to calculate the risk cluster type. Therefore, the flood disaster risk level is confirmed and then the local conditions for presenting the control strategy. This study takes the Tunxi area, Huangshan city, as an example. After dynamic risk assessment model establishment, verification and application for flood disasters between the actual and simulated data from 2001 to 2013, the comprehensive risk assessment results show that the development trend for flood disaster risk is still in a decline on the whole, despite the rise in a few years. This is in accordance with the actual conditions. The proposed model is shown to be feasible for theory and application, providing a new way to assess flood disaster risk. 相似文献
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Coastal flood risk will likely increase in the future due to urban development, sea-level rise, and potential change of storm surge climatology, but the latter has seldom been considered in flood risk analysis. We propose an integrated dynamic risk analysis for flooding task (iDraft) framework to assess coastal flood risk at regional scales, considering integrated dynamic effects of storm climatology change, sea-level rise, and coastal development. The framework is composed of two components: a modeling scheme to collect and combine necessary physical information and a formal, Poisson-based theoretical scheme to derive various risk measures of interest. Time-varying risk metrics such as the return period of various damage levels and the mean and variance of annual damage are derived analytically. The mean of the present value of future losses (PVL) is also obtained analytically in three ways. Monte Carlo (MC) methods are then developed to estimate these risk metrics and also the probability distribution of PVL. The analytical and MC methods are theoretically and numerically consistent. A case study is performed for New York City (NYC). It is found that the impact of population growth and coastal development on future flood risk is relatively small for NYC, sea-level rise will significantly increase the damage risk, and storm climatology change can also increase the risk and uncertainty. The joint effect of all three dynamic factors is possibly a dramatic increase of the risk over the twenty-first century and a significant shift of the probability distribution of the PVL towards high values. In a companion paper (Part II), we extend the iDraft to perform probabilistic benefit-cost analysis for various flood mitigation strategies proposed for NYC to avert the potential impact of climate change. 相似文献
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随着城市人口的增加,越来越多的超高层建筑在中国各大城市涌现,在其全寿命周期内不可避免的会遭受风甚至地震等多灾害的作用。以上海中心大厦为分析模型,根据其场地条件,采用Benowitez在2015年提出的1种基于随机波的模型方法模拟不同高度处具有空间相关性的脉动风荷载时程。通过对Perform 3D有限元软件建立的上海中心大厦模型进行非线性动力时程分析,研究地震和风耦合作用下对于结构性能的影响,并基于多灾害需求生成结构在地震和风耦合作用下的易损性曲面来研究结构的抗振可靠度。结果表明:结构的响应和易损性随着风速和PGA的增大而显著增大;随着风速的增大结构的响应和易损性均有增大的趋势,但随着地震动的增大,风荷载对结构响应和易损性影响逐步减小。 相似文献
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Comprehensive flood risk assessment based on set pair analysis-variable fuzzy sets model and fuzzy AHP 总被引：10，自引：1，他引：9
Qiang Zou Jianzhong Zhou Chao Zhou Lixiang Song Jun Guo 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(2):525-546
On the basis of the disaster system theory and comprehensive analysis of flood risk factors, including the hazard of the disaster-inducing factors and disaster-breeding environment, as well as the vulnerability of the hazards-bearing bodies, the primary risk assessment index system of flood diversion district as well as its assessment standards were established. Then, a new model for comprehensive flood risk assessment was put forward in this paper based on set pair analysis (SPA) and variable fuzzy sets (VFS) theory, named set pair analysis-variable fuzzy sets model (SPA-VFS), which determines the relative membership degree function of VFS by using SPA method and has the advantages of intuitionist course, simple calculation and good generality application. Moreover, the analytic hierarchy process (AHP) was combined with trapezoidal fuzzy numbers to calculate the weights of assessment indices, thus the weights for flood hazard and flood vulnerability were determined by the fuzzy AHP procedure, respectively. Then SPA-VFS were applied to calculate the flood hazard grades and flood vulnerability grades with rank feature value equation and the confidence criterion, respectively. Under the natural disasters risk expression recommended by the Humanitarian Affairs Department of United Nations, flood risk grades were achieved from the flood hazard grades and flood vulnerability grades with risk grade classification matrix, where flood hazard, flood vulnerability and flood risk were all classified into five grades as very low, low, medium, high and very high. Consequently, integrated flood risk maps could be carried out for flood risk management and decision-making. Finally, SPA-VFS and fuzzy AHP were employed for comprehensive flood risk assessment of Jingjiang flood diversion district in China, and the computational results demonstrate that SPA-VFS is reasonable, reliable and applicable, thus has bright prospects of application for comprehensive flood risk assessment, and moreover has potential to be applicable to comprehensive risk assessment of other natural disasters with no much modification. 相似文献
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Assessment of social vulnerability to natural hazards in the Yangtze River Delta, China 总被引：7，自引：3，他引：4
Yi Ge Wen Dou Zhihui Gu Xin Qian Jinfei Wang Wei Xu Peijun Shi Xiaodong Ming Xin Zhou Yuan Chen 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(8):1899-1908
China is exposed to a wide range of natural hazards, and disaster losses have escalated over the past decade. Owing to the pressure from natural disasters, along with changes in climate, social conditions, and regional environment, assessment of social vulnerability (SV) to natural hazards has become increasingly urgent for risk management and sustainable development in China. This paper presents a new method for quantifying SV based on the projection pursuit cluster (PPC) model. A reference social vulnerability index (SVI) at the county level was created for the Yangtze River Delta area in China for 1995, 2000, 2005, and 2009. The result of social vulnerability assessment was validated using data of actual losses from natural disasters. The primary findings are as follows: (i) In the study area, the major factors that impact SVI are regional per capita GDP and per capita income. (ii) The study area was more vulnerable in 1995 than in later years. SV of the whole region had decreased over the study period. (iii) Most part of Shanghai and the southeast part of Jiangsu Province had been the least vulnerable within the region. From this least vulnerable zone to the periphery of the region, the situation deteriorated. The highest SVI values in all evaluated years were found in the northern, western, or southern tips of the Yangtze River Delta. 相似文献
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Comprehensive assessment of flood risk using the classification and regression tree method 总被引：4，自引：2，他引：2
Zhonghui Ji Ning Li Wei Xie Jidong Wu Yang Zhou 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(8):1815-1828
The Evaluation of flood risk is a difficult task due to its numerous and complex impact factors. This article built a classification and regression tree (CART) model for the flood risk assessment with the available data of Hunan Province. This model is able to extract the major impact factors from many complex variables, determine the factors’ thresholds, and evaluate the levels of flood risk objectively. To construct the model, 18 explanatory variables were selected as the influential factors, including meteorological conditions, surface conditions and social vulnerability. Economic loss density from flood was chosen as the response variable for the quantitative and comprehensive evaluation of flood risk. The final model showed that meteorological conditions have the most significant influence on flood risk. Additionally, the relationship between meteorological factors and flood risk is rather complex. The variability of rainstorm days during the seasonal alternate period from the end of spring (May) to the early summer (June) is the source of the highest flood risk. In addition, the regional embankment density and population density as social vulnerability indicators and the relief degree of land surface as a surface condition indicator were also included in the flood risk assessment for Hunan. A region with dense dams appeared at a relatively higher risk. Densely inhabited areas with greater topographical relief also demonstrated a higher flood risk in the study area. The conditions obtained from the final tree for different levels of risk demonstrate the objectivity of selecting impact factors and a reduction of complexity for the risk evaluation process. Furthermore, the evaluation of high-level risk using the proposed method requires fewer conditions, which allows for a rapid risk assessment of serious floods. The CART method shows a decreased root mean squared error compared with that of a multiple linear regression model. In addition, the cross-validation error was improved for the high-risk levels that represent the most important classes in risk management. The verification with the available historical records showed that the output of the model is reliable. In summary, the CART method is feasible for extracting the main impact factors and their associated thresholds for the comprehensive assessment of regional flood risk. 相似文献
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Guo-Fang Li Xin-Yi Xiang Yi-Yi Tong Hui-Min Wang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(7):1683-1693
The Yangtze River Delta region is the region with highest urbanization speed in China. In this study, 6 typical urbanization areas in Yangtze River Delta were selected as the objectives of study. Flood risk assessment index system was established based on the flood disaster formation mechanism, and analytic hierarchy process was utilized to define the weight of indices. The flood hazard, the exposure of disaster bearing body, the vulnerability of disaster bearing body and the comprehensive flood risk corresponding to three typical years in different urbanization stages, 1991, 2001 and 2006 were assessed. The results show that the flood hazard and the exposure of disaster bearing body in the 6 areas are all with an increasing trend in the process of urbanization, among which, the increasing trend of the exposure of disaster bearing body is especially obvious. Though the vulnerabilities of disaster bearing body in the 6 areas are all with decreasing trend owe to the enhancement of flood control and disaster mitigation capability, the comprehensive flood risks in the 6 areas increased as a whole, which would pose a serious threat to urban sustainable development. Finally, effective countermeasures for flood risk management of urbanization areas in Yangtze River Delta were put forward based on the assessment results. 相似文献
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Marco GEMMER 《湖泊科学》2003,15(Z1):173-183
本文回顾了欧洲洪水影响评价技术.突出的问题是怎样处理洪灾及如何使洪灾损失降到最低.很明显在长江流域开展洪水风险和潜在的损失评价非常有意义.而现有的欧洲洪水影响评价技术难以在长江流域直接运用.我们对其进行了若干修正,并引入了基于GIS/RS的综合水文水动力和最小损失评价模型,该模型己经较好地运用于长江流域洪水影响评价的研究项目. 相似文献
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洪涝风险图的编制与应用——以太湖流域湖西区为例 总被引：1，自引：1，他引：0
洪涝风险图的编制,是洪涝平原管理中的一项重要内容,对洪涝平原生产布局和人类经济活动具有指导作用。本文介绍了一种洪涝风险图的编制方法。首先概化平原内河图,用明渠一维非恒定流模拟水流运动,得到各地的水位和流量,比较水位和数学地形模型（ＤＥＭ）的高程,将水位高过ＤＥＭ的地方划为洪涝危险区,本文以太湖流域湖西区为例作出洪涝风险图,并且介绍了洪涝风险图在国民经济部门的应用。 相似文献
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In northern regions, river ice‐ jam flooding can be more severe than open‐water flooding causing property and infrastructure damages, loss of human life and adverse impacts on aquatic ecosystems. Very little has been performed to assess the risk induced by ice‐related floods because most risk assessments are limited to open‐water floods. The specific objective of this study is to incorporate ice‐jam numerical modelling tools (e.g. RIVICE, Monte‐Carlo simulation) into flood hazard and risk assessment along the Peace River at the Town of Peace River (TPR) in Alberta, Canada. Adequate historical data for different ice‐jam and open‐water flooding events were available for this study site and were useful in developing ice‐affected stage‐frequency curves. These curves were then applied to calibrate a numerical hydraulic model, which simulated different ice jams and flood scenarios along the Peace River at the TPR. A Monte‐Carlo analysis was then carried out to acquire an ensemble of water level profiles to determine the 1 : 100‐year and 1 : 200‐year annual exceedance probability flood stages for the TPR. These flood stages were then used to map flood hazard and vulnerability of the TPR. Finally, the flood risk for a 200‐year return period was calculated to be an average of $32/m2/a ($/m2/a corresponds to a unit of annual expected damages or risk). Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Flood hazard and risk assessment was conducted to identify the priority areas in the southwest region of Bangladesh for flood mitigation. Simulation of flood flow through the Gorai and Arial Khan river system and its floodplains was done by using a hydrodynamic model. After model calibration and verification, the model was used to simulate the flood flow of 100‐year return period for a duration of four months. The maximum flooding depths at different locations in the rivers and floodplains were determined. The process in determining long flooding durations at every grid point in the hydrodynamic model is laborious and time‐consuming. Therefore the flood durations were determined by using satellite images of the observed flood in 1988, which has a return period close to 100 years. Flood hazard assessment was done considering flooding depth and duration. By dividing the study area into smaller land units for hazard assessment, the hazard index and the hazard factor for each land unit for depth and duration of flooding were determined. From the hazard factors of the land units, a flood hazard map, which indicates the locations of different categories of hazard zones, was developed. It was found that 54% of the study area was in the medium hazard zone, 26% in the higher hazard zone and 20% in the lower hazard zone. Due to lack of sufficient flood damage data, flood damage vulnerability is simply considered proportional to population density. The flood risk factor of each land unit was determined as the product of the flood hazard factor and the vulnerability factor. Knowing the flood risk factors for the land units, a flood risk map was developed based on the risk factors. These maps are very useful for the inhabitants and floodplain management authorities to minimize flood damage and loss of human lives. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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基于云南省建水县的建筑物、人口数量、生命线工程、地形地貌等数据,选取地震灾害损失风险评估因子,利用评估模型对设定烈度下可能造成的人员死亡、房屋破坏、滑坡密度等进行计算,给出地震灾害损失定量评估结果。在传统风险评估方法基础上,对无法建立灾害损失关系的承灾体用风险暴露量来代替灾害损失量进行风险评估。最后应用极差变换法对地震灾害损失的不同因子进行标准化,通过综合赋权划分地震灾害风险等级。结果表明:建水县地震灾害高风险的乡镇有5个,主要分布在建水北部的曲江,南部的南庄、西庄、临安、官厅一带;中风险乡镇有6个,低风险乡镇有3个。 相似文献