温德河流域暴雨洪水时空特征及模拟分析

受降雨和地形影响,吉林省温德河流域季节性洪灾频繁。为了解温德河流域暴雨洪水规律,利用2017年7—8月3次山洪灾害的暴雨洪水监测资料,采用自主研发模块化小流域分布式水文模型模拟了流域的洪水过程,取得较高的模拟精度。并结合研究区春登河、西阳河及五里河等三个主要河段的模拟流量和暴雨时空分布特征,分析三场暴雨时空分布对洪水造成的影响,总结了该流域2017年山洪灾害产生原因。结果表明:①温德河流域三场超标准洪水由短历时强降雨引起,"雨洪同向"的降雨锋面移动特点使洪峰呈现陡涨陡落之势;②"7·13"和"7·19"洪水的降雨时空集中程度和暴雨中心分布的差异影响两场洪水洪峰峰型、流量和各河段的洪量贡献比,造成温德河流域不同程度的灾害。

Analysis on temporal and spatial characteristics of rainstorm and flood simulation in Wendehe Watershed

Affected by rainfall and topography,seasonal floods frequently occur in the Wendehe watershed in Jilin Province.In order to learn the law of rainstorm and flood in Wendehe watershed,three rainstorm flood monitoring data from July to August in 2017 are selected.A self-developed modular small watershed distributed hydrological model is developed to simulate the flood process in the study area,and the simulation results has good agreement with the observed one.Combined with the simulated discharge and temporal and spatial distribution characteristics of three branches(Chundeng River,Xiyang River and Wuli River),we analyze the influence of the spatial and temporal distribution of the three rainstorms on the flood events,and then summarize the causes of mountain flood disaster in 2017.The results show that:(1)Three super standard floods in Wendehe watershed are caused by short-duration heavy rainfall,and the characteristics of rainfall front movement of“rain and flood in the same direction”make the flood peak rise and fall sharply.(2)The difference of the spatial and temporal concentration of rainfall and the distribution of rainstorm centers between the“7·13”and“7·19”floods affect the peak type,discharge and the flood contribution ratio of each tributary,resulting in different degree of disasters in Wendehe watershed.