Application of AquaCrop model for maize under water and nitrogen managements in a humid environment
Ebrahim Amiri1, Meysam Abedinpour*2
Globally, it is well debated fact that the water productivity in agriculture needs to be raised in order to meet the increasing demand for the feed and food production, which will double by 2050. Simulation models have been developed for predicting the effects of soil, water and nutrients on growth and water productivity of different crops. In this study, AquaCrop model was calibrated for grain maize (Single Cross 260) using drip irrigation system under varying irrigation and nitrogen levels. The intervals of irrigation were 6 days (F1), 12 days (F2) and 18 days (F3) which combined with different nitrogen levels of 0 (N1), 120 (N2), 180 (N3) and 240 kg ha-1. Root Mean Square Error (RMSE), normalized Root Mean Square Error (RMSEn), Mean Absolute Error (MAE), Prediction error (Pe) and coefficient of determination (R2) were used to test the model performance. The model was calibrated for simulating maize grain and biomass yield for all treatment levels with the prediction error 0.37<Pe<1.5 percent, 0.87<R2<0.92 and 0.8<RMSE<1.37 t ha-1. The results of the study showed that the AquaCrop model simulated aboveground biomass and grain yield in normal conditions more accurately than moderate and severe water stress conditions.
Keywords: AquaCrop model, Calibration, Maize, Nitrogen, Interval irrigation