The Hysteresis Phenomenon in the Soil Layer in the Wet and Dry Season

Studies on the drying of the ground in the Hachirogata Lagoon (VI)

Abstract

We have recognized hystere3is phenomenon in the seasonal change of trafficability and ground water table in the field of Hachirogata Lagoon.
This phenomenon is closely related to soil caracteristics which alter by the wet and dry condition.
We have found out that there is sometimes on increase of trafficability even in the wet season when the trafficability usually decreases.
In order to clarify this phenomenon, we have measured the pF-moisture ratio, dispersion ratio, sediment volume and shrinhage ratio, etc.
It was concluded that this phenomenon occurs when there apper cracks in the soil layer and moderate supply of water accelerates hardening of marshy heavy clay soil.