Lindane Diffusion in Soils: II. Water Content, Bulk Density, and Temperature Effects

Abstract

AbstractThe diffusion of lindane in Gila silt loam is strongly influenced by soil water content, bulk density, and temperature. The diffusion coefficient is nearly zero in soil of 1% water content. With an increase to 3% water content, which is equivalent to two layers of water between the montmorillonite clay plates, water is able to displace the lindane from the adsorbing surface so that the diffusion coefficient becomes maximal. A small additional increase in water content reduces the diffusion coefficient to about one‐half of the maximal value. This value then remains constant with increasing water content up to saturation. Decreasing bulk density or increasing temperature raises the diffusion coefficient. The influence of bulk density and temperature on diffusion is in good agreement with theoretical calculations.