面向逐日产沙模拟的SWAT模型封闭与检验  

Closure and validation of a SWAT model for daily scale sediment simulations

作　　者：李二辉 王冰洁 傅旭东[1] LI Erhui;WANG Bingjie;FU Xudong(State Key Laboratory of Hydroscience and Engineering.Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室

出　　处：《清华大学学报（自然科学版）》2019年第12期975-980,共6页Journal of Tsinghua University(Science and Technology)

基　　金：国家重点研发计划项目(2016YFC0402406)

摘　　要：针对SWAT(soil and water assessment tool)模型逐日产沙模拟中含沙量-流速关系的尺度匹配问题,给出了日尺度产沙模拟的最大含沙量封闭关系。该文采用黄河中游砒砂岩区9个水文站长系列实测水沙资料,确定日输沙率-日流量的幂函数型关系曲线,提供了SWAT模型日尺度最大含沙量的封闭关系。并将封闭的SWAT模型用于皇甫川流域水沙产输过程模拟,采用空间嵌套的皇甫站和沙圪堵站实测资料进行模型验证。结果表明:皇甫站率定期和验证期日输沙过程的Nash-Sutcliffe效率系数(Nash–Sutcliffe efficiency coefficient,NSE)分别为0.70和0.66,决定系数R^2分别为0.74和0.68;沙圪堵站率定期和验证期NSE分别为0.78和0.72,R^2分别为0.78和0.74;未进行封闭模型的沙圪堵站率定期和验证期NSE分别为0.36和0.26,R^2分别为0.39和0.26。表明封闭后的SWAT模型显著提高了模拟效率,能够用于黄土高原砒砂岩地区泥沙逐日过程模拟。A closed relationship for daily maximum sediment concentration was developed to solve the scale matching problem between the sediment concentration and the flow velocity in the SWAT model.A power function was used to fit the daily flow rate to the sedimentation flux at 9 gauging stations located in the soft sandstone region of the middle Yellow River to provide a closed relationship for the daily sedimentation rate.The closed SWAT model was then used to simulate the sediment transport in the Huangfuchuan watershed of the Yellow River.The model was validated by comparing the observed and simulated sediment loads at the Huangfu and Shagedu stations.The results showed that the Nash-Sutcliffe efficiency coefficient(NSE)was 0.70 and the determination coefficient(R^2)was 0.74 during the calibration period and were equal to 0.66 and 0.68 during the validation period for the daily scale sediment load at the Huangfu station.The closed SWAT model predictions at the Shagedu station correlated with the observed sediment load with NSE=0.78 and R^2=0.78 for the calibration period and NSE=0.72 and R^2=0.74 for the validation period.The unclosed SWAT model had NSE=0.36 and R^2=0.39 for the calibration period and NSE=0.26 and R^2=0.26 for the validation period at the Shagedu station.The results indicate that the closed SWAT model improves the simulation accuracy for sediment transport within the basin to improve applications of the SWAT model in the soft sandstone region for sediment simulation.

关 键 词：SWAT模型 输沙率-流量关系曲线 封闭关系 日尺度 皇甫川流域 

分 类 号：TV143[水利工程—水力学及河流动力学]