Infiltration into Two-Layered Soil Profiles

ABSTRACT RESULTS from the Modified GAML model, a simpli-fied model for predicting infiltration into two-layered soil profiles, were compared to observed data and results generated by numerical solution of Richards' equation. Both coarse-over-fine and fine-over-coarse stratifications were examined. The Modified GAML model closely approximates Richards' equation for two-layered soil profiles. Agreement between predictions of the Modified GAML and Numerical models and observ-ed data ranged from excellent to fair. Layering sequence significantly influenced the infiltration behavior of two-layered soil profiles. Infiltration rates and infiltration volumes were significantly lower for fine-over-coarse, than for coarse-over-fine stratifications.