基于GIS技术小流域水环境容量控制单元流量的推求

Flow Calculation of Environmental Capacity Controlling Units in a Small Watershed Based on GIS Technology

[目的]基于GIS技术,推求小流域水环境容量控制单元的流量。[方法]采用ArcGIS9.0对清潩河进行水文分析,结合市控断面设置情况划分"水-陆"响应的控制单元;应用等值线图法、径流系数法和水文比拟法,推算控制单元的最枯月(90%保证率)汇水流量;综合考虑废水入河量和上游来水,计算各控制断面的最枯月流量,并取临颖高村桥断面计算值与2010年实测值进行对比。[结果]临颍验证结果表明,临颍高村桥断面最枯月流量计算值与2010年实测值分别为6.03、5.93 m3/s,相对误差为1.69%,说明推求结果合理。[结论]该控制单元划分方法合理,流量推求结果准确,能够满足水环境容量测算精度。

[Objective] We aimed to calculate the flow of controlling units in a small watershed based on GIS technology.[Method] Hydrologic analysis on Qingyi River was conducted by using ArcGIS9.0,and the controlling units with response of water-land were divided according to the assignment of controlling sections;considering the wastewater entering the river and the water from its upper reach,the flow of controlling sections in the driest month（with guarantee rate of 90%） was calculated by means of isoline,runoff coefficient and hydrologic analogy method,and the calculated value of Gaocun Bridge sections in Linying was contrasted with the measured value in 2010.[Result] The result showed that the calculated value and measured value in 2010 of Gaocun Bridge section in Linying in the driest month were 6.03 and 5.93 m3/s respectively,with relative error of 1.69%,which revealed that the result of calculated flow was reasonable.[Conclusion] The way to divide controlling units was reasonable,and the result of flow calculation was accurate and can meet the precision of water environment capacity calculation.