极端洪水灾害损失评估方法及应用

Assessment method for extreme flood disaster losses and its application

极端洪水灾害具有频率低、影响范围大、损失高等特点,一般常遇洪水的灾害损失评估方法难以适用。分析了极端洪水灾害的自然属性与社会属性,认为极端洪水灾害损失具有时空分布的特性,因此借鉴空间信息格网技术,分别形成了极端洪水水文特性格网与社会经济特性格网,并将其叠加得到具有空间拓扑关系和属性信息的基于GIS的极端洪水损失空间信息格网模型,从而有效地反映了极端洪水灾害的时空特性。结合极端洪水损失率数据库,可评估极端洪水灾害损失。利用该方法评估了1998年特大洪水造成哈尔滨市江南主城区的直接经济损失,实证说明该方法可用于极端洪水灾害损失的评估。

Extreme flood is characterized with low frequency but large affecting area and huge economic loss. The natural and social attributions of extreme flood disaster were analyzed in the paper. The Current assessment methods are mainly used for common frequently-occurr^l flood, but not suitable for extreme flood. The spatial information grid of hydrological characteristics and social economic attribution for extreme flood were constructed through referencing the spatial information technology. In further, the spatial information grid model of extreme flood losses was established with the spatial topological relationship of different grid information. The model can not only reflect the spatial characteristics of extreme flood, but also assess the losses of extreme flood through combining relevant database. The model was employed to assess the direct economic loss in main city district north to Songhuajiang River in Harbin City, which indicates the model is feasible in practice for extreme flood disaster losses assessment.