Modeling of infiltration dynamics using HYDRUS-1D: Optimizing micro-sprinkler selection for reduced groundwater contamination risk in strawberry production in Florida, USA

Florida's strawberry industry relies on high-volume impact sprinklers for transplant establishment, applying over 25 mm per event and creating substantial risks of agrochemical losses on sandy soils. This study used HYDRUS-1D simulation with parameter inversion and Sobol global sensitivity analysis to quantify water partitioning within furrow zones of four micro-sprinkler systems relative to conventional impact sprinklers (IS) during the 11-day establishment period. The model reproduced soil moisture dynamics with good accuracy across irrigation systems (root mean square error, RMSE = 0.016–0.046 cm³/cm³; mean absolute error, MAE= 0.014–0.040 cm³/cm³; percent bias, PBIAS= −0.25% to +8.8%). Sobol analysis revealed that residual water content dominated model predictions (total-order sensitivity index ST = 0.88; first-order S1 =0.60), accounting for 60% of the output variance, and 28% through interactions, while saturated hydraulic conductivity exerted minimal influence (ST = 0.07). Cumulative furrow infiltration varied nine-fold among systems (p < 0.0001): IS generated 62.7 cm/day, Senninger Mini-Wobbler 54.5 cm/day (87% of IS), Netafim SuperNet 43.6 cm/day (70%), Senninger Xcel Wobbler 34.5 cm/day (55%), and Jain Mini Revolver (MR) 7.0 cm/day (11%, 89% reduction). Complete infiltration with zero runoff in highly permeable Candler sand (calibrated Ks = 16 cm/h) meant these differences translated proportionally into leaching susceptibility. The MR system combined the lowest infiltration with the highest water-use efficiency. Switching from IS to MR could prevent ∼5570 m³ /ha of deep percolation during establishment, equivalent to 55.7 million m³ annually across Florida’s strawberry production area. Irrigation system selection is a practical lever for groundwater protection in sandy-soil plasticulture strawberry. • HYDRUS-1D inverse solution achieved RMSE ≤ 0.046 cm³ /cm³ across five systems. • Residual water content exhibited dominant Sobol sensitivity (ST=0.88, S1 =0.60). • Cumulative furrow infiltration varied nine-fold (7.0–62.7 cm/day) among systems. • Mini Revolver system reduced deep percolation 89% relative to impact sprinklers. • System-specific infiltration directly governs leaching susceptibility in sandy soils.