The method determines the soil moisture content under constant preset pressure potential (ranging from -10 to -1500 kPa [0.1 atm to 15 atm]). Soil is brought to near saturation and then is allowed to equilibrate under a set atmospheric pressure potential. The method is used to determine the available water capacity of soils and/or moisture release curve. The method detection limit is 0.5%.
Klute, A. 1986. Water retention: laboratory methods. p. 635-662. In: A. Klute (ed.) Methods of soil analysis: Part 1. Physical and mineralogical methods. ASA Monograph Number 9.