Simulation of Soil Moisture and Yield for Wheat Using AquaCrop Model under Field Conditions in Neyshabur Plain

This study was conducted to simulate water balance components at field scale, predict soil moisture profile, and grain yield in irrigated wheat fields in Neyshabur plain. In this regard, three farms were selected in different parts of the plain. AquaCrop input data including air, soil, and crop parameters were collected at each farm separately, then, the required model parameters and wheat crop data were calibrated. Root mean square error (RMSE), model efficiency (EF) and prediction error (Pe) were used to evaluate the model performance. The results of moisture simulation in soil profile showed that the model correctly simulated moisture content at different depths and times. The statistical parameters used for evaluating efficiency of the model at the calibration stage for simulating soil moisture in all farms were 0.027<RMSE<0.032, 0.80<EF<0.91, and 3.5<Pe<14%. These values at model validation stage were 0.025<RMSE<0.031, 0.82<EF<0.94, and 2.7<Pe<12%. The minimum and maximum percentages of model simulation error for grain yield and water productivity in all farms managed by the farmers were 4-8.8% and 4.6 to 9%, respectively. According to the results of the research, AquaCrop model can simulate soil moisture content, grain yield, and water productivity with acceptable accuracy under similar field conditions.