Two-Dimensional Surface Flow and Solute Transport Model for Basin Irrigation with Conventional Fertilization

Abstract

The authors propose a two-dimensional surface flow and solute transport model of basin irrigation with conventional fertilization. Specifically, based on the mean velocities and water depth obtained from the complete hydrodynamic model, the nonmean water flow velocities along the basin surface plane and vertical direction was constructed by use of the linear-log law in turbulence and the continuous equation of incompressible hydrodynamics. Based on these constructed velocities, the advection-diffusion equation, which can describe nonuniform solute concentration along the basin surface plane and vertical direction, was employed to describe the two-dimensional basin surface solute transport. Based on the experimental data, the proposed model was validated. The results show that the curves from the observed and simulated results are in sufficient agreement, and the proposed model can successfully simulate the basin surface water flow and solute transport for basin irrigation with conventional fertilization. The analyzed results, based on the Markov stochastic process, show that the proposed model can simulate practical effects by approximately 71.09–87.93%. The other stochastic effects, approximately 12.07–28.91%, would be simulated when the model contains other stochastic factors, such as the spatial variation of the soil physical parameters, fertilizer uniformity applied on the basin surface, and so on.