Improving Irrigation Scheduling of Wheat to Increase Water Productivity in Shallow Groundwater Conditions Using Aquacrop

Abstract

Abstract Irrigation scheduling plays a key role in increasing crop production and controlling soil salinity in arid and semi‐arid regions. Inappropriate irrigation scheduling is considered an effective factor in low water productivity and soil salinization in central and southern parts of Khuzestan. Therefore, the aim of this research was to improve irrigation scheduling in order to increase water productivity and maintain the water and salt balance in a district in central Khuzestan. AquaCrop was selected as the research model, and the effects of the scenarios on wheat grain yield, water productivity, salt and water content in an effective root zone, and salt content moved upward from the groundwater table by capillary rise were compared with each other. Various scenarios of irrigation scheduling were simulated for a 12‐year period (2003–2014). To collect the required data for calibration and validation of the model, a field experiment was carried out during the wheat growing season (2014–2015). The results of the model evaluation indicated that it was an appropriate one for simulating the water and salt balance in the soil and wheat grain yield under different irrigation scheduling scenarios in experimental conditions. Finally, the recommended irrigation scheduling for wheat was seven times of irrigation with 550 mm water consumption. © 2018 John Wiley & Sons, Ltd.