Convective Transport of Ammonium With Nitrification in Soil

Dispersion equations with first-order reaction rates for nitrogen transformations were applied to describe the convective transport of NH 4 + with nitrification and denitrification in soil. The equations describing the concentrations of NH 4 + , NO 2 − and NO 3 − as functions of position, time, rate constants, average solution velocity and the distribution coefficient of NH 4 + between soil and soil solution were obtained. Several values of parameters were chosen to obtain the concentration profiles of NH 4 + , NO 2 − and NO 3 − along the soil column at several times. Steady-state concentration profiles and the time required to attain the steady state are discussed.