Coupled crop and solid set sprinkler simulation model.: I:: Model development

The development of a coupled crop model (Ador-Crop) and solid set sprinkler irrigation model (Ador-Sprinkler) is reported in this work. The crop model incorporates many of the features developed in the well-known CropWat model. Improvements include the use of thermal time and the input of daily ET0. The solid set sprinkler model applies ballistic theory to determine water distribution resulting from water droplets subjected to a wind vector. Regarding the validation of the coupled model (AdorSim), the plot of soil available water versus measured and simulated yield reduction resulted in similar features. AdorSim explained 25% of the variability in measured yield reduction. Most of the unexplained variability is due to the effect of nonwater-related factors affecting crop yield. In a companion paper, AdorSim is used to investigate optimum water management options in the middle Ebro basin in the NE of Spain.