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Technical Report

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Groundwater, denitrification, dynamic programming, solute transport, waste disposal


A PC/AT computer model was developed to simulate the transport of water, nitrate and ammonia in the soil profile after an application of poultry litter to pasture. The model was written using FORTRAN 77 compiler and can be used on any IBM type compatible computer with a math coprocessor. Poultry litter has been shown to be a potential source of plant nutrients, but mismanagement can result in nitrate pollution of the surface and groundwater. The model is composed of a main program, 11 subroutines and three subprograms. An example was shown of the flexibility and dynamic nature of the computer model. The redistribution and transformation of NH4 and NO3 in the soil profile was followed for 84 days. Output of the NH4 and NO3 concentration distributions, plant uptake and cumulative soil solution concentrations of these ions in the soil profile on a weekly basis was shown.

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