ABSTRACT
The value of the partition coefficient is a function of soil and chemical compound properties. Several important soil properties that greatly affect the magnitude of the partition coefficient include the fraction of organic carbon and the moisture content. In certain situations, in particular in unsaturated soils, time dependent diffusion coefficient models arise. Moisture content, and thus equilibrium partitioning, of exposed soil often varies with time, for example, effects due to the diurnal cycle in a dry climate. A mathematical analysis, which outlines the effect of time-dependent soil-air partition coefficient on the dynamics of a contaminant species. Several cases are then presented, where the soil-air partition coefficient varies with time in a small, finite depth. Evaluation of the general solution is very much influenced by the functional form of the air-soil partition coefficient with respect to time.
