Salt and water redistribution in freezing unsaturated soil

M. MIZOGUCHI, Mie Univ., Mie 514, Japan 

Soil freezing phenomena are subject to solutes. Since salt in soils 
induces the freezing point depression of soil water, conventional 
model can usually not be used to predict the movement of woter in
freezing soil. This study gives an experimental result of the 
simultaneous transport of water, heat and salt in a freezing soil. 
The redistribution of water, salt and temperature were ,measured in 
a freezing unsaturated saline soil. Salt moved from unfrozen to 
frozen area together with water. but the apparent solute concentration, 
which is defined asthe weight ratio of salt to water and ice,  was at 
the minimum near the freezing front. This result can be explained in 
terms of the migration of unfrozen water in which the solute 
concentration gradient is against the unfrozen water content gradient. 

M. Mizoguchi, (81)592-31-9574, mizo@bio.mie-u.ac.jp