Calibration and Validation of WOFOST Model for Wheat in Qazvin Plain

This study was carried out to calibrate and validate the WOFOST model for winter wheat in Qazvin plain. Firstly, the model was calibrated based on the phenological data obtained from the field experiment during the year 2016-2017. Then the model was validated based on the four years field data. After that the model recalibrated in terms of physiological aspects using leaf area index, biomass and crop yield. The model simulated flowering and maturity dates with 11 and 4 days accuracy (RMSE). The simulation results showed an acceptable fitness with the observation data. After calibration, the root mean square errors (NRMSE) of simulated model were estimated to be 12.05, 11.1 and 15.4% for yield, biomass and leaf area index, respectively. Based on the obtained results, the model was estimated all the proposed parameters less than the field data (CRM<0). The highest model efficiency was obtained for leaf area index. After that the model efficiencies were 0.95 and 0.94 for crop yield and biomass, respectively. The lowest value for determination coefficient (CD) was obtained for biomass, showing the largest dispersion between simulation and measurements values.