Validation of the FERTI-drip model for the evaluation and simulation of fertigation events in drip irrigation

FERTI-DRIP tool was developed to support decision-making in the fertigation process. The model determines the distribution of fertilizers at the subunit level, along with emitter discharge. FERTI-DRIP enables users to optimize the design of the irrigation subunit and the type and discharge of the installed emitter. Additionally, it helps determine the injection, advance, and cleaning times of fertilizer. Despite all these capacities, FERTI-DRIP has not been validated in a real irrigation system. Thus, the objective of this work has been to develop and implement a methodology to evaluate the actual distribution of fertilizers in a commercial productive environment and to calibrate FERTI-DRIP for this purpose.

This methodology has been applied in a commercial farm of 9 ha of almond trees (Prunus dulcis var. avijor), which is equipped with a drip irrigation system, intensively analyzing a fertigation event under real operating conditions.

This study has enabled the validation of the FERTI-DRIP tool, developing a methodology for evaluating fertigation systems that characterizes the distribution of fertilizers and their dynamics during an irrigation event. With the validation of FERTI-DRIP, a real fertigation process has been simulated, achieving a maximum time lag of three minutes and differences in the amount of fertilizer applied by each emitter of <1 %. This enables decision-making regarding fertilizer application times. The model has accurately predicted the dose of fertilizer, the application and cleaning times at the dripper level, thereby improving application efficiencies and mitigating issues arising from salt accumulation in the subunit through proper time management.