Numerical Modeling of Unsaturated Flow to Provide Guidelines for Hydraulic Conductivity

Abstract

Recent research has shown that Ground Penetrating Radar (GPR) techniques can be used to estimate the hydraulic conductivity of soil in the shallow subsurface at the field scale. GPR data can be acquired quickly and with high resolution, so this technique could offer substantial improvements in understanding variability in near-surface hydraulic conductivity. However, to apply GPR techniques for hydraulic conductivity estimation, data must be acquired before and after a wetting event such as irrigation, and to meet the mathematical requirements of estimation, steady-state vertical flow conditions must be established in the soil during the wetting event. This project seeks to define the soil and wetting characteristics needed to establish steady-state vertical flow over a defined depth so that GPR techniques could be used to estimate hydraulic conductivity.