DIFFUSION OF SALTS IN SOIL

Diffusion of salts in soil is a relatively intensive process. The coef ficient of diffusion, D, averages n x 10(-6) cm(2)/s. Its value varies in different soils and genetic horizons. In the presence of other sal ts, ion diffusion can become slower. The D becomes greater as moisture content, temperature, and the gradient of concentration increase. The last typically occurs for the ions that interact with the soil. The r eason for this is the change in soil properties resulting from these i nteractions. Temperature increase over a certain limit decelerates the diffusion of ions interacting with the soil adsorbing complex (K+, Na +). This is explained by increased ion absorption by the soil at high temperature.