承灾体脆弱性评估指标的最优格网化方法——以淮河干流区暴雨洪涝灾害为例

Study on the optimal grid method in assessment of vulnerability to floods disaster——A case study in the mainstream of Huaihe River Basin

选取淮河干流区基于社会经济数据的9种脆弱性指标,构建了暴雨洪涝灾害承灾体脆弱性评估体系,运用Arc GIS与Mat Lab软件实现面积权重法、面积占优法、中心点法和长度占优法对各脆弱性评估指标的格网化表达;利用熵值法改进的层次分析法对各指标赋值并进行4种算法下的脆弱性评估。结果表明:(1)面积权重法是单指标格网化过程中的最优算法,格网化结果与源数据间的均方根误差最小。(2)4种算法得到的格网化结果均无面积损失,面积权重法对所得评估结果的极值有一定程度的削弱作用,所得脆弱性评估结果在空间分布上基本与实际灾损情况一致。(3)淮河干流区暴雨洪涝灾害承灾体脆弱性高值区域主要分布在中部,中高值区域主要沿高值区的两侧向东西扩展,低值区主要分布在西南和东北两角。

Nine vulnerability indexes such as social and economic data of the Huaihe River Basin are selected to construct the vulnerability assessment system of the rainstorm floods disaster. This study achieved the area weight method,area dominance method,center point method and length dominance method by ARCGIS and MATLAB to mapping the vulnerability of each vulnerability assessment index,and finally explore the optimal grid expression of each vulnerability assessment index. Furthermore,the analytic hierarchy process improved by entropy method was used to assign each index,and evaluates the vulnerability under the four algorithms. The results are as follows：（ 1） The area weight method is the optimal algorithm in the process of single index grid,and the root mean square error between the grid result and the source data is the smallest.（ 2） The results of the four algorithms have no loss of area,and the area weight method has a certain degree of weakening effect on the extreme value of the obtained evaluation results. The results of the vulnerability assessment are basically consistent with the actual disaster situation in the spatial distribution.（ 3） Huaihe River basin of rainstorm floods vulnerability high value area of hazard bearing bodies are mainly distributed in the central. The high value area mainly spread out on both sides along thehigh value area expansion. The low value areas are mainly distributed in the southwest and northeast corners.