The Change and Distribution of Soil Moisture (V)

Ice-columns and soil moisture in field

Abstract

The author observed the relation between ice-columns and soil moisture of an upper layer inKanto-loam field (wheat field), Saitama Pref.
As it was difficult to clear up a small change of soil moisture during ice-columns growth, some methods of small sample theory and of the trial-error were adapted in treating the observed data.
The results are:
1) The depth of the soil layer where soil moisture moves is about 30cm.
2) Water contents of ice-columns changes linearly with soil moisture in an upper layer.
3) Under the weather conditions in which out-door temp. is lower than 0°C with no wind, etc, most ice-columns are seen in field capacity, and no ice-columns in about 28%(volume) of soil moitsure.
4) During ice-columns season, the relation between evaporation from soil surface and soil moisture in an upper layer is almost linear in wheat field.