Abstract
The soil layer in an upland field of kuroboku soil is devided roughly into a surface soil layer and subsoil layer. The physical properties of soil are considerably different between them.
This study demonstrated that the differences in the thickness of the surface soil layer has influence on the quantitative variation, consumptive use and vertical movement of soil moisture in the several soil layers of vertically different depths. The writers gave particular attention to the variation of matric potential in comparatively deep soil layers. Soil layer depths of the examination ranged from the surface to 170 centimeters.
Two test plots of considerably different surface soil thickness were investigated comparatively and contrastively. As a result of this examination, it was clarified that the aspects of vertical movement and comsumptive use of soil moisture were considerably different depending on the disparity of boundary depth between an A-horizon and B-horizon.
This paper is the result of an examination, which was performed in a test field of continuous long-term yearly use of the three major nutrients of chemical fertilizers. This study was performed in the agricultural experimental field of Ikuta school of Meiji university, and the nature of the soil is Kanto loam soil layer.
