济南主城区不透水地表分布分析及其水文效应

以济南市主城区范围为研究区,通过现场调研、遥感解译和划分标记的手段获取并探究其不透水地表分布。研究发现,济南市主城区范围内绿化率达到33.9%,不透水面积占比为65.3%。采用HIMS-SWMM模型进行小时尺度径流模拟,据此探究济南市主城区范围内各行政区不透水地表格局下其径流系数的变化情况。以2016年7-8月降雨作为输入,整个研究区共降水125.23mm,下渗量为36.33mm,产生的径流量为88.9mm,整个济南市主城区总体径流系数为0.71。各用地类型的不透水面占比与径流系数有较强的线性关系,其变化分为阈值型和渐变型。对于阈值型用地类型,可进行较为集中的绿化措施或LID措施;对于渐变型用地类型,可采用放缓的逐步绿化或LID措施,在集中改善阈值型用地类型的不透水面占比的同时,辅以较小范围的改善措施,以达到较为经济有效的防止内涝目的。

Analysis of the impervious land surface pattern distribution and its hydrological effects in the main urban area of Jinan

The impervious surface distribution is explored through field investigation, remote sensing interpretation and marking in the main ur ban area of Jinan. The study is revealed that the greening rate in the main urban area of Jinan reached 33.9% , and the proportion of the impervious area is 65.3% , respectively. The HIMS2SWMM model is used to simulate the hourly scale run-off, and the variation of t he runoff coefficient under the impervious surface distribution of each administrative district in the main urban area of Jinan City . Taking the rainfall from July to August 2016 as input, the whole study area has total precipitation of 125.23 mm, the infiltr ation amount is 36.33 mm, and the generated runoff is 88.9 mm, respectively . The overall runoff coefficient of the main urban area of Jinan is 0.71. The proportion of the impervious surface of each land type has a strong linearrelationship with the runoff coefficient, and the change is divided into threshold type and gradual type. For the threshold type of land use, more concentrated greening measures or LID measures can be carried out. For the gradual type of land use, slow gradual greening or LID measures can be adopted, which can improve the proportion of impervious water surface of the threshold type of land use in a cent ralized way , supplemented by a smaller range of improvement measures, aiming to achieve more economical and effective prevention of city floods.