平原集水区城镇化对暴雨洪水影响研究 ——以常州市双桥浜为例

城镇化下土地利用变化影响了流域洪水过程，并可能导致设计洪水发生变化。为进一步辅助城镇化流域防洪设计研究，以常州市双桥浜集水区为例，针对城镇化地区管网资料不全、区域管网河（渠）道排水过程复杂的问题，利用城市河道、道路、集水井等的汇水路径对高度城镇化小区进行子汇水区划分，基于HEC-HMS（Hydrologic Engineering Center-Hydrologic Modeling System）模型建立了适合高度城镇化下平原集水区的降雨-径流模拟模型，以模拟分析城镇化下土地利用转变对暴雨洪水的影响。结果表明，城市绿地向城镇化转变的过程较未利用地向城镇化转变使洪水增加得更大更快，且洪峰的增加幅度小于洪量的增加幅度。同时，随着土地利用转换程度的增大，对洪水影响的差异性也在增大，且低重现期洪水所表现的差异性更为明显。研究结果可为平原河网地区防洪减灾提供一定参考依据。

Impact of Urbanization Change on Flood Process in the Plain Catchment:A Case Study of Shuangqiaobang Community in Changzhou City

The effects of land-use change on the watershed flood process have become one of the major hydrological concerns in the world. A change in the flood process leads to the alteration in flood design and control system, which has caused serious problems to human life and urban security. To investigate the impact of urbanization on the rainstorm flood, the Shuangqiaobang community in Changzhou City was chosen as the typical highly-urbanized region. An improved method to divide runoff plots was proposed by considering the combination of rivers, roads and drainage sumps to establish a suitable HEC-HMS（Hydrologic Engineering Center-Hydrologic Modeling System）model for a highly-urbanized region. Based on this, the rainstorm flood processes under different return periods were simulated by the different land use situations. The results show that the increase of rainstorm flood would be bigger and more rapid under the transformation process from grassland to urbanization than that from land to urbanization, and the increase rate of peak discharge is less than that of flood volume. With the degree of transformation from other land use patterns to urbanization increase, the differences among the impacts of the different land use patterns on the rainstorm flood increase, especially the impact on the rainstorm flood under low return periods. The results of this study can provide scientific supports for the flood control and water resource management.