Factors influencing salt and water movement near crystalline salts in relatively dry soil

Abstract

Crystalline salts were placed at one end of sealed tubes of initially uniformly wet soil. The effect of soil texture, the initial soil water content, temperature, and the particular salt used on the resulting water and salt distributions in the soil was studied. In all experiments using relatively dry soil a zone of water accumulation adjacent to the salt, and a zone of water depletion further away from the salt, developed. Dissolved salt moved into the wetter zone next to the salt. The rate at which salt dissolved and moved out into the soil was found to depend very strongly on the solubility and saturated solution vapour pressure of the salt used, and the initial soil water content. Soil temperature and texture were less important factors. In some experiments quite large amounts of water accumulated in the crystalline salt, apparently when adequate contact was not maintained between the salt and the soil as the salt dissolved.