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

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.

Evaluation and Application of the AquaCrop Model in Simulating Soil Salinity and Winter Wheat Yield under Saline Water Irrigation

“…In general, the AquaCrop model accurately predicted the soil moisture in the 0 cm to 60 cm layer under various irrigation levels and water salinities. The robust capability of AquaCrop to simulate volumetric soil water content was also identified by several studies that tested AquaCrop for wheat, maize, and cotton applied with different irrigation strategies and saline conditions [23,38,39]. In the study, saline water irrigation increased the volumetric soil water content during the winter wheat growing seasons, which could be mainly attributed to the reduced evapotranspiration under salt stress [12].…”

“…The solute transport of the root zone is complex and can be affected by several factors, such as meteorological conditions, soil dispersion, adsorption, and root extraction [23,34]. Moreover, the overestimated volumetric soil water content in the root zone might indicate reduced upward salt movement through the capillary rise, thus leading to lower soil salinity during simulation [39].…”

Modelling root water uptake under deficit irrigation and rewetting in Northwest China

“…Complex crop responses to water stress have continually been a research focus of deficit irrigation (Andarzian et al., ; Iqbal et al., ; Mkhabela & Bullock, ; Steduto, Hsiao, Raes, & Fereres, ; Toumi et al., ). Many studies have analyzed the relationships between crop growth, ET, and RWU (Goosheh, Pazira, Gholami, Andarzian, & Panahpour, ; Han et al., ; Jha et al., ), while others have studied crop growth and ET under deficit irrigation (Salemi et al., ; Yu, Zeng, Su, Cai, & Zheng, ). Andarzian et al.…”

“…Complex crop responses to water stress have continually been a research focus of deficit irrigation (Andarzian et al, 2011;Iqbal et al, 2014;Mkhabela & Bullock, 2012;Steduto, Hsiao, Raes, & Fereres, 2009;Toumi et al, 2016). Many studies have analyzed the relationships between crop growth, ET, and RWU (Goosheh, Pazira, Gholami, Andarzian, & Panahpour, 2018;Han et al, 2017;Jha et al, 2017), while others have studied crop growth and ET under deficit irrigation (Salemi et al, 2011;Yu, Zeng, Su, Cai, & Zheng, 2016). Andarzian et al (2011), Benabdelouahab et al (2016) and Mkhabela and Bullock (2012) evaluated the performance of the AquaCrop model for its ability to simulate wheat yield and SWC under different irrigation scenarios.…”

The AquaCrop model – Enhancing crop water productivity

“…Hassanli et al, 2016) and groundwater (e.g. Goosheh et al, 2018) features, accounting for nine, four, and two percent of all publications, respectively (Figure 3.22). Furthermore, of the studies that have used the fertility module only 39 percent have performed a local soil fertility calibration, even though it is considered a prerequisite before conducting any fertility-limited simulation.…”