**2.3 Sorption kinetics experiments**

The sorption of P has been assumed as a kinetic process [15, 28]. Three initial concentrations (C0), 19, 29, and 38 mg L<sup>−</sup><sup>1</sup> were used for conducting sorption kinetics experiment. The A horizon of Immokalee soil was used for sorption kinetics experiment, and the soil to solution ratio of 1:2 (10 g of soil and 20 mL of solution) was used. Solution concentrations were analyzed after 4, 8, 12, and 24 h. The paired t-test was used to identify significant differences in relative concentrations (C/C0) and sorbed concentrations between fertilizer mixture and supporting electrolytes. R-software was used for statistical analyses. Graphs of relative concentrations (C/C0) and sorbed concentrations (S) versus time were plotted to show the data trends over a 24 h period.
