Determining soil water diffusivities from one-step outflow experiments

Abstract

A simple and accurate method is developed for calculating soil water diffusivities, D(è), from one-step outflow experiments. The method is based on the assumption that dè/dt is effectively constant throughout the draining column of soil at any given time. The method is accurate to within about 15 % over most of the range of è during the outflow, providing that D increases monotonically with è through that range.