基于FloodArea的山洪灾害风险区划研究——以淠河流域为例

Rainstorm-Induced Mountain Flood Disaster Risk Zoning Based on FloodArea Inundation Model-Taking Pihe River Valley as A Case

致灾临界面雨量、洪水淹没范围及深度的确定是暴雨山洪灾害风险区划的核心环节。本文以淠河流域为研究区,利用统计方法与水文模型相结合的方法确定雨-洪关系,得到致灾临界面雨量;基于FloodArea开展洪水淹没模拟,叠加承灾体信息,得到T年一遇洪水淹没风险评估与区划图。通过对2015年13号台风"苏迪罗"强降水过程的淹没反演,验证表明:无论是洪水淹没范围还是淹没水深,FloodArea模拟值与实况值均较为吻合。综合来看,淠河流域暴雨山洪灾害风险区划与评估结果较为合理;基于FloodArea模型在淠河流域具有较好的洪水淹没模拟效果,可用于暴雨洪涝灾害风险评估与预警。

Ifs essential to determine the areal precipitation thresholds of rainstorm-flood disaster, flood inundation scope and water depth for rainstorm-induced mountain flood disaster risk zoning. A case was performed for Pihe River Valley, which lies in Anhui province. Relationship between hydrological elements and rainstorm during typical flood process was analyzed in order to explore the relationship between rainstorm and floods by using statistical methods and hydrological model. With water level records of historical floods, the areal precipitation thresholds of rainstorm-flood disaster were obtained further. The flood inundation simulations were carried out by using the FloodArea model. Furthermore, the maps of rainstorm-induced mountain flood disaster risk assessment and zoning were estimated based on different recurrence periods by overlapping the information of disaster-bearing body. The inundation induced by Soudelor, which was the most serious typhoon in recent years, was simulated dynamically. The inundation risk assessment and zoning were proved to be reasonable by contrasting the simulated results with the actual disaster investigative records about the flooding scope and maximum water depth. The results show that the operational procedure of the rainstorm and flood disaster loss evaluation based on rainstorm and flood inundation model has a clear physical basis, the FloodArea model could be employed in the risk evaluation and early-warning of rainstorm and flood disasters.