Effect of soil physical parameters on nitrate diffusion (with 15N) in sterilized soils

Effect of soil physical parameters on nitrate diffusion, showed that the apparent self diffusion coefficient of nitrate-nitrogen (DaNO3) decreased from 3.06 x 10-6 to 0.70 x 10-6 cm2/sec and from 3.89 x 10-6 to 0.91 x 10-6 cm2/sec in sandy loam and loam soils, respectively with the increase in soil moisture tension from 0.10 bar to 2.00 bar. The DaNO3 was found to increase from 1.82 x 10-6 to 2.68 x 10-6 cm2/sec and 2.16 x 10-6 to 3.30 x 10-6 cm2/sec in sandy loam and loam soils, respectively with the increase in bulk density from 1.35 to 1.60 g cm-3; and from 1.86 x10-6 to 4.46 x10-6 cm2/sec and 1.97 x 10-6 to 3.75 x 10-6 cm2/sec in sandy loam and loam soils, respectively with an increase in ambient temperature from 5degC to 30 degC. The carrier NO3-N did not affect the DANO3 in both the soils. The transmission factor was found to decrease from 1.79 x 10-1 to 0.41 x 10-1 and 2.27 x 10-1 to 0.53 x 10 -1 in sandy loam and loam soils, respectively with the increase in soil moisture tension from 0.10 bar to 2.00 bar. The increase in bulk density, ambient temperature and carrier NO3-N levels did not show appreciable effect on the transmission factor in both the soils. (author). 13 refs., 6 figs., 4 tabs