城市建设对暴雨内涝空间分布的影响研究——以武汉市主城区为例

Impact of urban development on the risk of flooding:A case study of Wuhan City,China

城市内涝灾害频繁,用地开发与空间扩张被普遍认为是其致因之一。对比武汉市遥感数据,1984—2017年,超过30%的自然水体被填占开发,城市建设开发活跃、填湖造陆强度大。论文以武汉市为例,采用二项Logistic模型,定量分析不同降雨强度情景下的内涝影响因素。研究表明,填湖造陆将极大地增加极端降雨情景下城市滨水区域的内涝风险。城市地形地势、排水管网条件、用地类型以及邻域用地结构等因素,也直接影响内涝风险。基于2种不同的用地开发策略,预测城市内涝风险结果显示,城市用地的不当开发将引致严重内涝风险。依据内涝风险的空间分布预测结果,论文提出了相应的改善策略,以为科学地制定防涝减灾规划提供参考。

Urban pluvial flooding is an increasing problem for cities worldwide.Urban spatial growth and development have been widely recognized as one of the most important contributors to the increasing risk of flood disasters.Using Wuhan City,China as a case,this study developed a binary Logistic model to quantify the impacts of urban development on flooding under different rainfall scenarios(regular and extreme),especially the role of land conversion from water areas.Based on historical remote sensing data,the analysis of the dynamic land use changes indicates that over 30%of water areas had been converted into urban construction lands from 1984 to 2017.The results show that the conversion of water areas severely intensified the flooding risk of the surrounding locations in the extreme rainfall scenario.In addition to this land conversion,elevation,drainage conditions,land use types,and land use of surrounding areas are also significantly correlated with urban flooding.Based on two land use and development strategies,the risk maps of future flooding were predicted under regular and extreme rainfall scenarios.These maps show that the development of the remaining vacant lands will induce even worse flooding.Adaptation strategies corresponding to different land use types are provided according to the predicted flooding risks.The model could help develop adaptation strategies and policies to cope with future urban flooding by exploring its driving factors.