On the Influence Given by the History of Drying to Physical Indexes

StudiesonthedryingofgroundintheHachir6gatalagoon (V)

Abstract

The influence given by the history of drying from the seasonal and yearly changes of the physical drying indexes (mainly, qc, pF, and groundwater table) in the marshy heavy clay soil of the Hachirogata lagoon were estimated.
Mainly the following matters were clarified in this study.
1. The history of drying is restored clearly.
2. The hydrophilic nature of soil becomes weaker and the water holding content decreases with the progress of drying.
3. The relation between pF and qc was evaluated and the reason that qc becomes large suddenly at the boundary of a certain integrated pan-evaporation.
4. The relation between the groundwater level and pF can be classified into three change patterns.
We are enabled to judge by these patterns in what stage the drying of soil is.