SOLUTE TRANSPORT THROUGH SOIL WITH ADSORPTION AND ROOT WATER UPTAKE COMPUTED WITH A TRANSIENT AND A CONSTANT-FLUX MODEL

Abstract

Computer models are often used to simulate solute transport through soil profiles. This paper compares the results obtained with two such models. The first model is rather complex and requires a complete description of the soil hydrological properties. The second model is much simpler and uses an average percolation rate as input. Solute transport was compared with and without adsorption and with and without root water uptake. The results show that the relative solute concentration at a given soil depth, as a function of cumulative drainage of an intermittently irrigated soil, is a smooth curve, which can also be simulated with the simple model. Such models are apparently appropriate for predicting solute transport through field soils with their inherent spatial variability in physical and chemical properties.