Simultaneous Change of Water Content, Solute and Temperature 
Profiles in a Partially Frozen Unsaturated Soil 

Masaru MIZOGUCHl*, Masashi NAKANO**

*Faculty of Agriculture. Mie University 
** Faculty of Agriculture, University of Tokyo 

Abstract 

Soil water content, solute and temperature profiles were measured 
in a partially frozen unsaturated sandy loam soil at two different 
initial water contents and at two different freezing temperatures, 
The water content increased with time in the frozen part of the soil 
and decreased in the unfrozen part of the soil. The amount of water 
migration in the soil with the high initial water content was greater 
than that in the soil with a low content. The solute profiles changed 
in a manner analogous to the water content profiles in the soil with 
the high initial water content whereas they were relatively uniform 
in the soil with the low content. The temperature profiles could be 
divided into three different region. a frozen, an intermediate 
between frozen and unfrozen and an unfrozen region. The length of
 the intermediate region was greater in the soil with the high initial 
water content than in the soil with the low content, and this length 
increased with time. The temperature of this region was determined 
by the initial water content and was equal to the temperature at 
which the soil water started to freeze.  It is considered that these 
results could be attributed to the rate of phase change from liquid 
water to ice in the intermediate region in which soil particles, liquid 
water, air and ice coexist.