The effect of bulk density, water content and soil type on the diffusion of chloride in soil

SUMMARY The relative importance of soil bulk density, water content and potential on the self‐diffusion and impedance factors of 36 C1 in a sandy loam and loamy clay were studied. The soil bulk densities used represented a range of conditions from freshly tilled seedbeds to compacted soils. The volumetric water contents and pF were the main factors controlling the soil impedance factors, with bulk density making a small but significant contribution. Soil type affects the impedance factors through differences in anion exclusion volumes, the water contents of poorly connected pores that contribute little to the diffusion process, and tortuosity of the diffusion pathways.