适用于分布式水文模拟的空间插值方法改进

An improved spatial interpolation method for distributed hydrological simulation

降水数据是水文模型重要输入数据之一,雨量空间插值是获得面雨量数据的有效方法。改进现有雨量插值方法,获取较为精确的逐日连续面域降水数据,并以补远江流域为例对改进效果进行验证,将插值后得到的降水数据作为输入条件,基于MIKE SHE水文模型模拟补远江流域径流过程,分析改进后的插值方法所得降水数据对模型精度的提高效果。结果表明:利用改进插值方法(简称IDW-Thiessen插值法)得到的降水数据,在模型模拟径流过程中的效果优于利用Thiessen多边形获得的降水数据;在补远江流域这一研究案例中,利用IDW-Thiessen插值法得到的降水数据模拟补远江日径流,所得结果的纳什系数在率定期和验证期都超过0.7,高于利用Thiessen多边形法得到的降水数据进行径流模拟结果的纳什系数;IDW-Thiessen插值法与Thiessen多边形得到的径流模拟结果相比,年平均误差减少10%,雨季模型模拟精度提高6%,旱季模型模拟精度提高了7%,模拟径流过程线与实测径流过程线更吻合。

Precipitation data is one of the important input data in the hydrological model.Spatial interpolation of rainfall is an effective method to obtain surface rainfall data.Therefore,it is very important to improve the existing rainfall interpolation methods to obtain more accurate continuous time series and surface precipitation data.MIKE SHE hydrological model was used to simulate the daily runoff using improved interpolated precipitation data to analyze the accuracy of the model in the Yuan Jiang Basin..Results exhibited that the precipitation data obtained by the improved method(IDW-Thiessen interpolation method)was better than Thiessen polygon in the process of runoff simulation.Therefore,daily runoff process was carried out by using the precipitation data obtained by IDW-Thiessen interpolation method in the Bu Yuan Jiang Basin.The Nash coefficients were higher than 0.7 during the calibration and validation periods compared to the Nash coefficients of the runoff simulation results obtained by Thiessen polygon method.The annual average error of IDW-Thiessen interpolation method was reduced by 10%,the simulation accuracy in the rainy season was improved by 6%,and the simulation accuracy in the dry season was improved by7%,respectively.Results also revealed that simulated runoff was comparable with the measured runoff.