User-Friendly Calculators for Estimating Water Flow in Variably Saturated Soils.

In this study we introduce a method to replace difficult numerical computations for calculating water content distribution and infiltration with an easier to use form at the student’s level. This concept leads to a simple, user-friendly, interactive Excel spreadsheet for estimating subsurface wetting patterns and infiltration. The spreadsheet is based on sound science using numerical modeling and artificial neural networks. The artificial neural networks are used to encapsulate the results from the numerical modeling into a predictive format. This procedure was tested successfully to describe water content distribution and infiltration from one and three-dimensional sources. In practice the user provides soil hydraulic properties, initial water content and boundary condition. The results are presented graphically showing precisely infiltration and fate of the added water. Further the calculators can facilitate simple optimization problems using Excel optimization tools.