11:45 AM - 12:00 PM
[AHW21-04] Assessing the capability of AquaCrop to simulate winter wheat and cotton production under semi-arid climate in Uzbekistan
Keywords:AquaCrop model, irrigation managements, winter wheat, cotton
The AquaCrop model, a widely recognized crop-water simulation tool maintained by the Food and Agricultural Organization of the United Nations, has a proven track record of accurately predicting the growth, canopy coverage, and grain yield of multiple crops in various climates. Despite its success, previous studies validating AquaCrop in arid or semi-arid regions have reported inconsistent results regarding the calibrated parameters for a particular crop. As a result, the validity of these datasets for use under semi-arid climate in Uzbekistan is uncertain. We address this research gap using multiple years of field data collected in Southern Uzbekistan's cold semi-arid climate to calibrate and validate AquaCrop focusing on winter wheat and cotton production, under various irrigation regimes.
An objective calibration method was devised that rigorously follows the guidelines of the AquaCrop model. The calibrated model adequately simulated biomass accumulation and canopy cover growth of winter wheat (Fig: observed and simulated a) biomass (ton/ha) and b) canopy cover (%) of winter wheat for 2011-2012, under basin and furrow irrigation managements (full and deficit schemes) using calibrated parameters). Simulations however indicated that crops encounter low temperature stress during their vegetative stage, severely lowing expected yield. Field observations do not suggest that crop experienced temperature stress. To accurately assess parameters related to cold stress tolerance, not accounted in the default variety used in the AquaCrop model, additional experiments conducted in a temperature-controlled environment are necessary.
Results from the field experiment and AquaCrop simulations both support the implementation of furrow deficit irrigation with winter wheat as a means of maintaining adequate grain yield while conserving water resources in this semi-arid region. The simulations contrasting furrow irrigation management (full and deficit) with mulching (use, not use) for cotton production are still outstanding.
An objective calibration method was devised that rigorously follows the guidelines of the AquaCrop model. The calibrated model adequately simulated biomass accumulation and canopy cover growth of winter wheat (Fig: observed and simulated a) biomass (ton/ha) and b) canopy cover (%) of winter wheat for 2011-2012, under basin and furrow irrigation managements (full and deficit schemes) using calibrated parameters). Simulations however indicated that crops encounter low temperature stress during their vegetative stage, severely lowing expected yield. Field observations do not suggest that crop experienced temperature stress. To accurately assess parameters related to cold stress tolerance, not accounted in the default variety used in the AquaCrop model, additional experiments conducted in a temperature-controlled environment are necessary.
Results from the field experiment and AquaCrop simulations both support the implementation of furrow deficit irrigation with winter wheat as a means of maintaining adequate grain yield while conserving water resources in this semi-arid region. The simulations contrasting furrow irrigation management (full and deficit) with mulching (use, not use) for cotton production are still outstanding.