jordpotential

jordpotential is a term used in some European soil science contexts to denote the soil water potential, the potential energy of water within soil. In English-language literature the standard term is soil water potential.

In its standard form, jordpotential is the total potential energy of water in soil, Ψ = Ψm + Ψo + Ψg, typically expressed in kilopascals (kPa) or megapascals (MPa). It describes the energy state of water in the soil system and governs the movement of water between soil, plants, and the atmosphere.

Matric potential Ψm arises from capillary and adsorptive forces between water and soil solids; osmotic potential Ψo from dissolved solutes in soil water; and gravitational potential Ψg from vertical height. The sum of these components gives the total soil water potential, which is usually negative in unsaturated soils and approaches zero in saturated conditions.

Measurement methods include tensiometers for unsaturated conditions, which deter­mine matric potential; pressure plates to determine the soil water retention curve; and psychrometers or dewpoint methods for osmotic potential. In field and laboratory settings, these techniques are used to estimate the total jordpotential and its components.

Applications include irrigation scheduling, drought stress assessment, and hydrological modeling; understanding jordpotential helps describe the tendency of water to move from soil to plant roots or through porous media. Terminology notes: jordpotential is used regionally in some Nordic and European texts; in English the preferred term is soil water potential, though the two refer to the same concept.