基于调查数据的县域山洪灾害风险评价技术研究

Research on flash flood risk assessment technology at county-scale based on investigation data

以县域为单元进行研究,提出一种基于前期山洪灾害调查评价基础数据的山洪灾害风险评价方法。通过分析山洪灾害致灾因子和承灾因子,采用GIS工具进行提取与处理,利用层次分析法(Analytic Hierarchy Process,AHP)计算各因子的权重,最后基于加权综合法叠加各图层获得山洪灾害风险图,根据调查的历史山洪灾害数据来验证结果的可靠性,以海南三亚市为例进行研究,研究结果表明,藤桥河、三亚河、宁远河流域山洪灾害风险等级较高,是山洪灾害的高发和易损区域。

Taking county as the base-unit,a flash flood disaster risk assessment method based on the basic data of previous investigation and evaluation is put forward. This paper analyzes the disaster-causing factors and disasterbearing factors of flash flood disaster extracted and processed by GIS tools. The weight of each factor is calculated by AHP(Analytic Hierarchy Process). Finally,the risk maps of flash flood disaster are developed by overlapping the layers based on the weighted synthesis method,which is verified by the historical data. Taking Sanya City as an example,the results show that the risk level of flash flood in the basins of Tengqiao River,Sanya River and Ningyuan River is higher,and there are the high incidence and vulnerable areas of flash flood.