evaluation of the aquacrop and ceres-maize models in assessment of soil water balance and maize yield

importance of fresh water in agriculture along with the essential demand of the growing population for food, indicates an extreme necessity of the optimum use of water. to this end, plant growth simulation models have been introduced in agricultural sciences to reach maximum yields in varying climates. variations in the of developed models cause difficulties for the unprofessional users. the aquacrop model, which is developed by fao is one of the plant growth simulation models which tries to improve the facility of the model by reducing the number of input data. throughout the present study, the aquacrop model was calibrated and validated for maize in karaj region by due attention to soil water balance. moreover, the results were compared with ceres-maize as a specific maize growth simulation model. the results indicated an appropriate function of both models in predicting yield and as well in soil water balance parameters. the figures 85-94 constituted the index of agreement for the aquacrop model in soil water simulation as compared with the figures within 58-64 for ceres-maize model. rmse figures in yield simulation for the aquacrop model stood within 40-20%, although for ceres-maize they varied from 20 to 80%. finally, and as regards the accuracy of the aquacrop model, it is a recommendable one to farmers, and to planners in karaj region.