A Solute Transport Model for Simulating Nitrate Infiltration Into Structured Soils.

A fertilizer nitrate module was developed and tested as an addition to the Mesopore and Matrix (M&M) infiltration model.  The updated M&M model couples an intra-aggregate and aggregate-mesopore nitrate diffusion approach originally developed by Addiscott (1977, 1981) with an easily parameterized infiltration model based on soil structure and other readily available soil data. The model was used to simulate nitrate leachate breakthrough and profile distributions in a silty clay loam soil.  Results were compared with field measurements and HYDRUS simulations.