SWAT模型在黄土丘陵区参数敏感度分析及率正研究

Study on the Sensitivity Analysis and Calibration of Parameter in SWAT Model

SWAT模型是基于水文过程的、具有很强物理机制的流域分布式水文模型。应用SWAT模型,结合1986—2000年罗玉沟流域实测水文资料对径流进行模拟,并进行了模型参数敏感度分析和率正。通过敏感度分析,辨析出影响该流域产流模拟结果精度的主要参数因子,如径流曲线数CN2等。依据上述结论调整参数值,对模型进行了率正和验证,得出率正期的相对误差为14.0%,R2为96.1%,Nash—Suttcliffe系数为0.89;验证期的相对误差为8.8%,R2为91.5%,Nash—Suttcliffe系数为0.82。结果表明实测流量和模拟流量的线性回归系数和模型的效率系数满足模型模拟的要求,SWAT模型适用于该研究区域。

The soil and water assessment tool（SWAT） is a physically based continuous event hydrologic model.This study carried out SWAT model to simulate the runoff with the measured data collected from Luoyugou watershed from 1986 to 2000.Based on the sensitivity analysis,the main parameters such as CN2 affecting the simulated values in the watershed were detected.The parameters were adjusted based on the above analyzed results.From the results of calibration,the relative simulated error was less than 14%;the relative coefficient and Nash-Suttcliffe coefficient were 96.1% and 0.89,respectively;and from the results of validation,the relative error was less than 8.8%,the relative coefficient and Nash-Suttcliffe coefficient were 91.5% and 0.82,respectively,which indicated that the model can simulate the runoff outputs in the study area with satisfaction.