漯河市规划区雨洪格局空间分布特征综合量化研究

目的]探索城市雨洪格局空间分布规律,为海绵城市建设提供参考。方法]建立GIS数据库,ArcGIS空间模拟与SCS-CN,SWMM模型相结合,定量分析20a重现期和2h,85.43mm降雨,漯河规划区产流和积水分布特征。结果]研究区径流量和径流系数(相等)、径流体积、峰值流量、积水区域的自相关Moran's I系数分别为0.338(p0.001),0.142(p0.001),0.101(p0.001),0.918(p0.001),表明产流与积水分布均呈现显著集聚性,土地类型和管网分布对产流影响大于积水过程,而地形影响则相反;径流量和径流系数由中心向外递减趋势,径流体积与峰值流量受汇水区面积和城市管网分布影响;高产流风险区不透水面占该区域82.73%,径流系数0.7和不透水面70%的汇水区集中在城市中心;积水区用地类型以农业用地、城市绿地、道路用地为主,分别占总面积的36.56%,21.39%,21.82%,分布特征存在显著差异。结论]城市地表结构变化与城市产流和积水分布关系密切,综合量化方法可以直观地反映城市雨洪格局特征与趋势。

A Quantitative Study on Spatial Distribution of Rain Flood Pattern in Luohe Planning Area

Objective] To explore the spatial distribution of rain flood pattern in order to provide references for the construction of sponge city.Methods] A GIS database was established, combined with ArcGIS simulation, SCS-CN and SWMM models, the characteristics of runoff and flood distribution were quantitatively analyzed in Luohe planning area.Results] Total runoff and runoff coefficient (equal), runoff volume, total peak, inundation area of Moran''s I coefficient was 0.338 (p<0.001), 0.142 (p<0.001), 0.101(p<0.001) and 0.918 (p<0.001), respectively, indicated that the distribution of runoff and inundation had a remarkable agglomeration. The impact of land type and pipe network distribution on runoff was greater than that of accumulated water process, but the influence of topography was opposite. Total runoff and runoff coefficient were decreased from center to outside. Total peak and runoff volume were affected by catchments area and pipe network distribution. The impermeable surface of the runoff high risked area accounted for 82.73% of the total area. The runoff risk decreased from center to outside. The catchment area of runoff coefficient > 0.7 and the inundation area > 70% were concentrated in the urban center. Agricultural land, urban green space and road land were the main types of land use in the inundation area, accounting for 36.56%, 21.39% and 21.82% of the total area, respectively, and there were significant difference in the distribution characteristics.Conclusion] Urban surface change was closely related to the distribution of runoff and inundation. The comprehensive quantification method could directly reflect the characteristics and trends of urban flood pattern.