Suitable land use is useful for urban drainage and storage of excessive rainfall.A laboratory simulated rain experiment shows that the water retention capacity of green land is higher than that of bare soil with the same rainfall intensity,especially with a low rainfall intensity of 20～25 mL/min.The difference in the water retention capacity of different underlying surfaces indicates that land use can adjust and store rainfall runoff,and provides a reference for future land use planning and ecological city construction planning.

下凹式绿地是一种具有渗蓄雨水、削减洪峰流量、减轻地表径流污染等优点的生态型排水设施。对不同设计参数的下凹式绿地雨水渗蓄能力的计算和分析表明:下凹式绿地面积比例f、绿地下凹深度Δh、绿地土壤稳定入渗速率K和设计暴雨重现期P是影响其雨水渗蓄效率N的主要因素。经分析计算,一般情况下的下凹式绿地设计参数选择范围为:绿地面积比例10%～30%,下凹深度0.1～0.3m,土壤稳定入渗速率大于5×10-7m/s,设计暴雨重现期可选择一年、三年和五年一遇标准。