SWAT在干旱半干旱地区的应用——以窟野河流域为例

SWAT application in arid and semi-arid region:A case study in the Kuye River Basin

SWAT是一个基于物理机制的分布式流域水文模型，其产流机制中对于地表径流、壤中流、浅层地下径流和深层地下径流的模拟方法比较实用，能够适用于不同气候条件和下垫面条件下的产汇流情况。本文将SWAT应用到黄河中游干旱半干旱区多沙粗沙典型流域之一窟野河流域，模拟了1980-1985年的日流量和月平均流量过程，分析并探讨了SWAT产流机制对水源划分和径流形成过程的影响。结果表明，水量平衡相对误差在10％～20％左右，但Nash—Sutticliffe效率系数都较低。本文对模拟结果进行了初步分析，认为SWAT产流机制不能有效模拟干旱半干旱地区的窟野河流域的壤中流、基流和春汛流量过程，并探讨了SWAT在干旱半干旱地区产流模拟可能存在的问题和值得深入研究的方向。

The SWAT is a physically-based distributed hydrological model.Its runoff generation mechanism is more practical.The methods adopted in the process of runoff including surface runoff,interflow and groundwater flow are applicable to various conditions of climate and underlying surface.In this study,the SWAT（Version 2005） is applied to the Kuye River basin,one of typical watersheds with plentiful and coarse sand in the middle reaches of the Yellow River with arid and semi-arid climate.When the model in the Kuye River basin was developed,automatic calibration method within the SWAT Version 2005 was used to calibrate the model.According to the stream flow hydrograph at Wenjiachuan station,the mouth of the river,the parameters were further adjusted.Then,daily and monthly discharges from 1980 to 1985 have been simulated in the study area,and observed data series of three hydrological stations（Wenjiachuan,Xinmiao and Wangdaohengta） are used to evaluate the simulated discharge series of SWAT.The effects of physical mechanism for streamflow generation processes have been analyzed and discussed.The result shows that the relative error of water budget is about 10%-20%,while the Nash-Sutcliffe efficiency coefficient（Ens） is relatively low,with Ens of daily series being about 0.2 and monthly Ens around 0.6.Preliminary analysis of simulation results showed that the SWAT is not effective to simulate the discharge of interflow,baseflow and spring flood in the Kuye River basin.In addition,it is proposed that the SWAT runoff generation mechanism in arid and semi-arid regions need to be further investigated.