基于GIS的乡镇级洪涝水淹风险研究

Research on flooding and inundation risk at township level based on GIS

洪涝灾害是最严重的自然灾害之一。乡镇排水系统差,相关数据与技术受限,脆弱性高,亟需技术支持。空间信息技术在洪涝灾害研究中主要采用被动遥感与GIS,但被动遥感数据获取困难,以灾后评估为主。提出了一种基于GIS的乡镇级洪涝水淹风险分析方法,服务于洪涝灾前评估;以湖北省随州市何店镇为研究区,主要应用开源数据资料,根据历史降雨、土壤和地形等特征分析不同重现期的降雨与积水过程,划分水淹风险等级,并提供避险建议。结果表明,研究成果基本符合实地调研情况,能够较准确地反映研究区水淹风险,可为乡镇级洪涝灾害科学决策提供有效的数据与技术支持。

Flood disaster is one of the most serious natural disasters.The poor drainage system,related data and technology limitations,and high vulnerability of townships lead to the urgent need for technical support in townships.Spatial information technology is mainly used in flood disaster research with passive remote sensing and GIS.However,passive remote sensing data is difficult to obtain and is mainly used for post-disaster assessment.In this paper,we propose a GIS-based method for township-level flooding and inundation risk analysis to serve predisaster assessment of flooding.The Hedian Town,Suizhou City,Hubei Province is taken as the study area,and the open source data information is applied to analyze the rainfall and waterlogging processes in different recurrence periods based on historical rainfall,soil and terrain characteristics,classify the flooding risk level,and provide evacuation suggestions.The results show that the research results are basically consistent with the field research and can reflect the flooding risk in the study area more accurately.The method of this paper can provide effective data and technical support for scientific decision-making on flood disaster at the township level.