城市不透水面与降雨径流关系研究

城市不透水面增加对降雨径流关系有着重要的影响，本研究选择位于福州城区内的厦坊溪和解放溪2个流域，在流域尺度上研究现状和城区未来扩展过程中对应的不透水率及其与降雨一径流关系．研究结果表明不透水率与径流系数在不同降雨情况下都成正相关的线性关系，尺。达到0．9以上；随着降雨量的增大并伴随着前期湿润度由干到湿变化，虽然不透水率对地表径流的影响有所弱化，但整体而言，城市不透水面的增加导致相同降雨情况下径流系数增加，并增大城市排水系统负担．利用研究结果，论文最后从保护河网水系、合理规划城区发展、完善排水系统和加强绿地系统建设等方面对城市规划提出建议．

On the Relationship between Urban Impervious Surface and Rainfall-Runoff

Increasing urban impervious surface coverage has important influences on the process of ur- ban rainfall-runoff. In watershed scale, the paper chose Xiafangxi watershed and Jiefangxi watershed in Fuzhou City to study the relationship between urban impervious cover and rainfall-runoff in actual situation and in the process of urban expansion. It can be concluded that the runoff coefficient has a direct response to the increase of impervious surface ratio under different rainfall conditions, with R2 more than 0. 9. With the increase of rainfall accompanied by AMC from to III, the impact of imper- vious surface ratio on runoff was weakening. In general, the increase of impervious surface ratio would cause the increase of runoff coefficient in the same rainfall event, leaving a heavy burden to the city＇s drainage system. Based on study results, we put forward proposals for urban planning from river net- work system protection, rational city planning, drainage system perfection and urban greening system construction.