岩溶泉域降雨径流水文过程的模拟——以重庆金佛山水房泉为例

通过地貌、水文地质、土壤、植被、地下洞穴管道等实地调查,以及示踪试验确定水房泉泉域范围和地下水文系统特征,并通过代表性点的土壤入渗试验、降雨和流量监测以及DEM数据等获得泉域水文模型所需的面积、结点高程、入渗率、糙率、管道长度、含水层孔隙度、出流系数等参数。选择SCS径流曲线模型估算地表产流,利用SWMM模型模拟泉域对场降雨的径流响应过程。通过运行模型,与实测流量比较,结果显示模拟曲线与观测流量曲线吻合较好,用于校正和验证的两场降雨产流的模拟误差分别为9.5%和12%,表明SWMM可应用于岩溶区以管道流为主要排水系统的含水介质的模拟。

Simulation of hydrological response of Karst spring to precipitation——Case study of Shuifang Spring, Jinfo Mt., Chongqing

This paper tried to simulate the process of hydrological response to precipitation of a typical karst spring-Shuifang spring with SWMM including geology and geomorphology,hydrology,coverage of soil and vegetation,main directions of surface and underground flowpaths,cave systems,depressions and swallow holes.The catchment area and connection between swallow holes and the spring were ascertained after twice dye tracing tests,two injection points for each one with yellow-green tracer Uranine and purple-red SulforhodamineB.Analyzing of dye tracing results confirmed conduit flow between one of the sinkholes in recharge area and outlet of the drainage system-Shuifang spring.Main parameters such as area,width,slope,permeable proportion,roughness of the sub-catchments,elevations of junctions,lengths,width,cross-section and roughness of conduits,porosity of aquifer,and coefficient of laminar groundwater flows into conduits through junctions and so on,are obtained under the observation,tests and analysis in ArcGIS.SWMM gave a good report of simulated flow rate of the spring,compared with the observed data,with errors of 9.5% and 12% for calibration and validation,respectively.Results show that SWMM is applicable in simulating karst aquifer with conduit flow system.