【作者】 尹占娥；

【导师】 许世远；

【作者基本信息】 华东师范大学 ， 第四纪地质学， 2009， 博士

【摘要】 城市自然灾害风险研究是国际灾害研究领域的前沿与热点问题。在全球自然灾害频发、强度不断增强的背景下，城市自然灾害风险研究更引起了国际社会和国内外学者的高度关注。在国家自然科学基金项目“中国沿海城市自然灾害风险评估体系研究”和重点项目“沿海城市自然灾害风险应急预案情景分析”的资助下，调查分析了中国沿海典型城市自然灾害发育特征及其风险管理，获得了大量的文献资料与数据基础上，借鉴国内外自然灾害风险研究进展的成果，从地球系统科学思想出发，分析了典型城市自然灾害风险系统主要特征，探讨城市自然灾害风险评估方法与理论，并应用遥感和GIS技术，剖析城市不同尺度下的自然灾害风险动态评估途径和范式，为城市综合减灾降险和风险管理决策提供科学依据。主要研究结果如下：1．国内外自然灾害分析实践表明，完全准确预报和阻止自然灾害发生并不现实，采用有效的自然灾害风险评估与管理战略，可以避免或减轻其带来的巨大损失。城市自然灾害风险研究的核心是人类社会环境暴露程度、承灾体脆弱性和风险表达。城市自然灾害风险系统具有连锁效应、放大效应和人为效应等基本特征。多元化数据获取手段和复杂系统仿真建模工具相结合，模拟人类活动干扰下的灾害发展演化过程，形成对灾害风险的动态综合评估。2．从地球系统科学思想出发，按照成因分类和分级序列原则，建立了城市灾害分类系统。第一级的自然灾害和人为灾害二大类对应于地球表层系统和人类活动系统，人类活动系统和地球表层系统是灾害形成的孕灾环境系统。第二级的气象灾害、水文灾害、地质灾害、生物灾害形成于地球表层系统的大气圈、水圈、岩石圈和生物圈；技术灾害和人为灾害形成于人与技术等人为作用；环境灾害是人地系统共同作用下的灾害类型，具有自然与人为的双重特点。第三级的灾种是各灾害类型按成因的进一步细分，如气象灾害有台风、冰雪、风暴潮等。这一城市灾害分类系统，从灾害形成的机理和不同的环境系统出发，有利于认别和分析各致灾因子形成灾害的孕灾环境，针对不同的孕灾环境，开展灾害的脆弱性和风险分析，提出相对应的减灾和降低风险决策与管理措施。3．构建了城市自然灾害系统、灾害风险系统与灾害风险评估之间的关系模型。城市自然灾害风险系统与灾害系统是两个相互关联的系统。风险系统是灾害系统的一个子系统。城市灾害系统包括孕灾环境、致灾因子和承灾体三个要素。而城市灾害风险系统是对灾害系统中致灾因子危险性分析，以及承灾体脆弱性分析和暴露要素分析。城市自然灾害风险表达是致灾因子、人类社会环境暴露程度和承灾体脆弱性三者共同作用下的可能灾害损失。4．提出了城市自然灾害风险评估的多尺度体系。城市自然灾害风险评估的尺度是与研究区域比例尺、空间分辨率、行政单元和数据精度相对应。根据自上而下和自下而上两种尺度研究方法，建立了市级、区级(城区)和社区级3个尺度开展灾害风险评估工作。市级尺度下，研究比例尺为1：500000～1：100000，对应分析单元的空间分辨率为250m～30m；区级尺度下，研究比例尺为1：100000～1：10000，对应分析单元的空间分辨率为30m～5m；社区尺度下，研究比例尺为1：10000～1：1000的比例尺，对应分析单元的空间分辨率为5m以下。不同的研究尺度，可采用不同的评估方法，大尺度研究一般用指标体系的评估方法，中小尺度的研究采用情景模拟和灾害现场调查方法。在同一尺度下也可采用不同的风险评估方法，对于同一种评估方法也可以应用于不同尺度下的研究，以满足不同的评估精度需求，形成多尺度的城市自然灾害风险评估。5．上海城市尺度自然灾害综合风险评估，选用指标体系的风险建模范式和方法。从致灾因子、历史灾情、暴露-易损性和抗灾恢复力出发，选取19个风险评估指标，建立了上海市自然灾害综合风险评估指标体系。以上海下辖各区县作为评估基本单元，采取特尔菲法与AHP相结合方法，确定各指标权重。经标准化处理，计算得到各指标因子指数和综合风险值，由低到高分为10个等级，基于GIS编制上海综合风险图。分析表明：①各区县暴露-易损性指数差别较大，最高的是黄浦区和静安区。②各区县的风险值基本处于风险等级的中段，黄浦区最高值为0．75，金山区最低值为0．38。③综合风险等级从上海中心城区向郊外辐射递减。④沿海区县风险值0．5以上，高于西部区县风险值0．4左右。该指标体系方法对于快速评估城市综合风险具有借鉴意义。6．静安城区暴雨洪涝灾害风险评估，采用基于情景分析的动态风险评估方法。应用遥感和GIS工具，从致灾因子、脆弱性和暴露分析出发，模拟出研究区8种不同重现期内1小时降雨的淹没区域和淹没深度情景，并以三维可视化方式显示模拟结果。通过实地调查与收集灾损数据，建立居民房屋和室内财产内涝淹没深度和损失率之间的关系曲线；通过人口和房屋被淹没状况的暴露分析，进行受灾人口与损失评估，并利用超越概率-损失曲线，建立了研究区风险序列，计算出年平均内涝损失数值，作为减灾的成本-效益分析。分析表明：①静安区8种重现期建立的超越概率-损失曲线，得出年平均内涝损失为342万元。②8种重现期暴雨内涝情景模拟，淹没最深处为50cm。③该风险评估方法，改进了城市内部地形模拟，提高了场景模拟的空间分析精度，使评估结果更为准确，可作为该尺度暴雨内涝风险管理依据。7．城市社区暴雨内涝灾害情景分析，以上海市浦东新区临园社区2008年9月20日暴雨内涝为例，采用现场调查方法，应用遥感和GIS工具，开展该次暴雨内涝灾害的多情景模拟。从致灾因子、脆弱性和暴露分析出发，实地测量不同积水点水深进行插值，模拟洪水淹没情景。根据居民房屋和室内财产暴露与灾损率，分别得到房屋和室内财产等损失，总损失为608732元，重现期为150年一遇，超越概率0．0067，暴雨内涝风险值(年平均灾害损失AAFL)约4079元，与实际灾损情况基本一致。这为城市社区尺度的暴雨内涝灾害数据获取与风险评估方法提供了一种新探索。城市自然灾害系统是个复杂系统，受多变量因素制约，导致灾害风险评估的复杂性和艰巨性。尽管本文对城市自然灾害风险研究进行了探讨，但仍有待深化，如重视城市灾害数据库构建，力求形成灾害数据管理的统一模板和共享平台；加强城市自然灾害风险实证研究，系统建立城市不同类型承灾体脆弱性灾损曲线；探讨城市不同尺度自然灾害风险评估范式，实现灾害综合风险的动态评估，为城市各级主管部门减灾降险和管理决策提供依据。更多还原

【Abstract】 Urban natural disaster risk is the spotlight in international disaster and abroad researchfield. Because both the frequency and the intensity of global natural disasteroccurrences are increasing, the research on urban natural disaster risk is drawing moreattention in international professional field as well as in domestic related field. In2005, the researcher of this paper take part in two National Science Fund Committeeprogrammes, which are Comprehensive Risk Assessment and Management ModeResearch on Natural Disaster in Coastal Cities, and key programme ScenarioAnalysis on Natural Disaster Emergencies in Coastal Cities. During the researchperiod, the researcher collects a great number of literatures and research data. On theadvanced bases, the paper summary the achievement of previous development innatural disaster risk research both in domestic and abroad for references. Starting fromearth systemic and scientific thought, the paper makes analysis on the maincharacteristics of natural disaster risk system and probes into the theories and methodsof natural disaster risk assessment. The paper apply Remote Sensing and GIStechniques to take apart the dynamic assessment ways and modes of natural disasterrisk in diverse scales cities, in order to provide scientific basis for urban disaster riskdecreasing and risk decision-making management. The followings are mainconclusions of the research:1.Research analysis and practices indicate that it is unrealistic to make exactforecasting and preventing natural disaster, but adopting the results of scientificnatural disaster risk assessment and strategic management can avoid or alleviate thegreat losses; Urban natural disaster risk may focus on the degree of human societyexposure to surroundings, the vulnerability of disaster acceptor; and risk express.Urban natural disaster risk system is provided with characteristics of chain dominoeffect, magnify domino effect and man-made effect, etc. Getting help frommulti-datum gaining methods and complicate system imitated to model, whichsimulates the evolvement process of disaster happening under the disturbing situation of human behavior, to make a dynamic assessment on disaster risk.2. Starting from earth systemic and scientific thoughts, the paper set up urban disasterclassification system according to cause of formation and grade sequence principle.Corresponding earth surface layer and human activity system, the natural disaster andman-made disaster belong to the first grade, which is the environmental system totrigger disasters. The second grade includes weather disaster, hydrological disaster,geological disaster, biological disaster, which are formed in atmosphere, hydrosphere,lithosphere and biosphere in the earth surface layer. And technological disaster andman-made disaster attribute to humankind and technique, and so on. Environmentaldisaster attribute to both humankind and nature, which is operated by humankindsystem and nature system altogether. The third grade is the further classificationaccording to the cause of formation of diverse disaster types, just as the weatherdisaster which has typhoon, ice and snow, storm tide, etc. Such kind of urban disasterclassification system based on cause of formation of disaster and environment system,it is propitious to recognize and analysis the surrounding which trigger to disaster, andin view of different surroundings, it can help to make analysis on risk andvulnerability, and put forward corresponding decision making and managementcountermeasures on disaster reducing and risk debasing.3. The paper built up a relation mode which connect urban natural disaster system,disaster risk system and disaster risk assessment. Urban natural disaster risk systemand disaster system has a lose relationship. Risk system is a subsystem of disastersystem. Urban disaster system contains pregnant disaster environment, hazards anddisaster acceptor. And urban natural disaster risk system based on the analysis on boththe danger of hazards and vulnerability of disaster acceptor, and further analysis onthe exposing elements processed by the hazards and vulnerability of disaster acceptor.Urban natural disaster risk may due to three points: hazards, the degree of humansociety exposure to surroundings, and the vulnerability of disaster acceptor; The papermakes an expression of disaster risk via disaster loss assessment and disastercost-benefit analysis. 4. The paper makes a probe into multi-scale system on urban natural disaster riskassessment. The urban natural disaster risk assessment is related to the scale ofresearch field, spatial resolution, administrative unit and the precision of data.According to both from top to bottom and from bottom to top two scales researchmethods, the paper formed city,district and community three scales to develop thedisaster risk assessment. City scale, research map scale 1:500000～1:100000, relatedunit spatial resolution 250m～30m, district scale, research map scale 1:100000～1:10000, related unit spatial resolution 30m～5m, community scale, research map scale1:10000～1:1000, related unit spatial resolution is below 5m. So different researchscale refer to different assessment methods, the big scale research generally use indexsystem assessment way, and middle and small scale research use scenario simulationand disaster investigation on scenario spot. And in order to meet the need of differentassessment precision, the same scale research can make use of different riskassessment methods, and the same risk assessment method can apply to different scaleresearches.5. Selecting index system risk modeling mode and method, based on hazards, disasterhistories, exposure and vulnerability, and resilience of disaster resisting, choosing 19risk assessment indexes, the paper set up Shanghai natural disaster integrated riskassessment index system. Taking all Shanghai municipal districts as assessing primaryunits, the paper makes use of Delphi method and AHP to certain each index value.The paper makes a processing of standardization to get each index factor andintegrated risk value, which has 10 grades from bottom to top, and make use of GIS tomap Shanghai integrated risk. It indicates:①There are great differences aboutexposure-vulnerability index in each districts, the greatest are Huangpu district andJing’an district.②2 The risk value of each district is in middle grade of risk grades, thegreatest is 0.75 in Huangpu district, the lowest is 0.38 in Jinshan district.③Theintegrated risk grades present radiate descending from Shanghai downtown to suburb.④The risk value of coastal districts is above 0.5, which is higher than the 0.4 in westdistricts. This index system method can be used for reference to assessing urban riskin a quick step. 6. Making use of dynamic risk assessment method based on scenario analysis, thepaper makes flood disaster risk assessment on Jing’an district. Starting from hazards,vulnerability and exposure analysis, and applying remote sensing and GIS to simulatedifferent scenarios of 8 return periods within one-hour-rain inundation area andinundation depth, and display the simulating result by three-dimensional visualizationway. And thorough field survey and data selecting, the paper makes a relation curvechart between the loss of citizen housing and treasure and the inundation degree. Thepaper makes assessment on population suffering from disaster and loss, according tothe exposing analysis on people and houses inundation situation, and makes use ofexceedance probability-loss curve to form risk sequence and count the AverageAnnual Flood Loss, which can help make cost-benefit analysis on disaster decreasing.The analysis indicates:①According to the exceedance probability-loss curve basedon 8 return periods situations in Jing’an district, the Average Annual Flood Loss is3.42 million.②2 According to 8 return periods scenario simulation on flood, thedeepest is 50cm.③The risk assessment method can advance urban DEM, andpromote the spatial analysis precision of scenario simulation, and it makes a moreexact assessment result, which can help flood risk management.7. Taking Linyuan community’s flood, Pudong district, Shanghai Sep. 20^th, in 2008 asexample, the paper makes several multi-scenario simulations with remote sensing andGIS, through the field survey. And it measures the different submerging spots andinterpolating base on the spots; simulate the flood scenario with the analysis ofhazards, vulnerability and exposure. According to citizen houses and contentsexposing and losing rate, it gets the total loss is 608732 Yuan, the return period is 150years, exceedance probability is 0.0067, the Average Annual Flood Loss（Risk value）is about 4079 Yuan, which is in line with the actual. This provides a new probe forflood disaster data collecting and risk assessment method in urban community scale.Urban natural disaster risk system is a complex system, and it is restricted by a lot ofdiverse factors, which leads to the complexity and difficulty of the whole disaster riskassessment system. The paper makes a research and discussion on urban naturaldisaster risk system, but it needs more hard work and study to make further developments in this field in future, which, for example, includes to pay moreattention to urban disaster data-base construction to provide the standard mode andsharing materials for disaster data management, to strengthen case study on urbannatural disaster risk, and to form the vulnerability curves of different type disasteracceptors, to study on natural disaster risk assessment mode in urban multi-scale torealize the dynamic assessment of integrated disaster risk, to provide foundation andcountermeasures on disaster decreasing and risk reducing for every level ofgovernment.更多还原