Sate about the Soil water potential

Electrical energy, potential energy and kinetic energy together are referred to as free energy or the energy status of water. The difference between the free energy of soil water and that of pure water in a standard reference state is termed soil water potential . It determines the state and movement of water in soils. It arises due to the position or internal conditions of soil water and is expressed relative to the energy conditions of free water. The potential of free water is arbitrarily taken to be zero.