Parameterization and comparison of the AquaCrop and MOPECO models for a high-yielding barley cultivar under different irrigation levels

This study describes the processes of calibration and validation of AquaCrop (the FAO water productivity model) and MOPECO (economic optimization model of irrigation water) for the simulation of a barley crop (cv. Cierzo). We compare the complexity of implementing this process in the two models and the accuracy of the results. A 3-year field experiment conducted during the period from 2011 to 2013 in a semi-arid region located in southeast Spain was used for this purpose. Six irrigation treatments were applied combining different levels of water deficit depending on the phenological stage. Both models were suitable for the simulation of yield and soil moisture evolution. In addition, AquaCrop correctly simulated the harvest index, the evolution of canopy cover and aboveground biomass. The comparison between the two models showed that AquaCrop is a better model for assessing the effect of a particular irrigation schedule on a crop (i.e. biomass and canopy cover development, soil water balance...) than MOPECO. Nevertheless, if the objective is to estimate yield depending on the irrigation schedule applied, MOPECO is easier to calibrate and furnishes results as valid as those provided by AquaCrop.