Psychrometric Measurement of Soil Water Potential without Precise Temperature Control

Abstract

Abstract A theoretical analysis shows that by imposing certain boundary conditions it should be possible to eliminate the major effects of temperature fluctuation on psychrometric measurements of soil water potential. Tests on a psychrometer constructed to meet these boundary conditions were carried out on a soil column in a greenhouse. Although diurnal fluctuation of soil temperature was as great as 5C, water potential was measured with an apparent accuracy of ±0.5 bars throughout two irrigation cycles.