Comparison of AquaCrop and SWAP for Simulation of Sugar Beet Yield and Water Use Efficiency under different Irrigation Intervals

Crop Models are useful tools for simulation of crops to environmental factors. In order to use crop model, it is necessary to evaluate their accuracies and efficiencies. So, the study was conducted to evaluate the accuracy and efficiency of AquaCrop and SWAP models for simulation of sugar beet under different irrigation intervals. Irrigation in four intervals (I1: 6, I2: 9, I3: 12 and I4: 15 days) during three continues year (Y1: first years, Y2: second year and Y3: third year) at Feiz Abad research station in Qazvin were studied. First year data was used for calibration and second and third year data were used for validation of both models. Results showed that both AqauCrop and SWAP had underestimate error for simulation of yield and water productivity. AquaCrop model (RMSE=1.79 ton.ha-1) had better accuracy compared to SWAP (RMSE=1.85 ton.ha-1) for simulation of yield. According to NRMSE, accuracy of both models was the same and classified in very good group. Efficiencies of both models (EF=0.99 and d=0.99) were acceptable. Regarding the results, it is proposed to use both models for simulation of sugar beet yield and water use efficiency.