ARS | Publication request: Two-Dimensional Numerical Simulation of Preferential Flow in a Tile Drained Field

Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 14, 1995
Publication Date: N/A

Technical Abstract: Modeling preferential flow of water in soil at different scales has been a continuous challenge for soil scientists. Mathematical hypotheses such as double porosity (deterministic) and transfer function (stochastic) models are some of the few approaches used to address preferential flow. These approaches have not been very successful at several scales of application because of a lack of information of the hydraulic and retention function o the different flow domains (e.g., soil matrix, cylindrical macropores, planar cracks) that coexist in a field condition. In this study, sequentially implemented, ponded infiltrometer, tension infiltrometer, and laboratory outflow measurements were used to model a new multi-modal hydraulic conductivity function over a wider range of soil water pressure heads. The new hydraulic conductivity function is used in the CHAIN_2D numerical field near Las Nutrias, New Mexico. Comparisons are made between the performance of the newly derived hydraulic conductivity function and the more classical hydraulic conductivity formulations for variably-saturated flow in the macroporous field soil.