VALIDITY OF THE SOIL WATER CHARACTERISTICS DETERMINED WITH THE PRESSURIZED APPARATUS

Abstract

It has been shown that the soil water characteristics curve determined with the pressurized apparatus may not represent the actual condition of soil water as encountered by the growing plant. Actual tension of soil water may be considerably less than that assumed to be applied in the pressure apparatus (at the same water content). This suggests the need for a careful examination of the pressure apparatus as a means of determining the energy status of soil water. The magnitude of the observed discrepancy is related to the amount of air bubbles trapped or nucleated in the water-filled pores. /Author/