Efficient Simulation of Surface Solute Transport in Basin Fertigation

Abstract

Numerical models are convenient for the management of basin fertigation. However, the characteristic line approach, commonly applied to solve the advection-dispersion equation, presents disadvantages such as numerical oscillation at the vertical position of the solute concentration wave caused by cubic spline interpolation. To address this problem, a new approach was constructed to solve the advection-dispersion equation. This new approach is a hybrid of the characteristic line and the finite-volume approaches. The zero-inertia equation with a standard diffusion wave type was used to describe the surface water flow, and a new model for basin fertigation was developed. Three basin fertigation experiments were carried out to validate the developed model. The results showed that the simulated solute transport processes did not exhibit any numerical oscillation and overcame the disadvantage of the characteristic line approach in conjunction with the cubic spline interpolation. Overall, the mass conservation ability of the developed solution for the advection-dispersion equation was significantly improved.