The first is to measure the amount of water in the soil. This approach is the basis for the soil condition water content. An alternative to measuring the amount of water in soil is to measure the energy state of the water. This approach leads to the soil condition water potential . Energy State of Water Water, like all matter, can posses both kinetic and potential energy.
Water potential characterizes the potential energy of water in soil.
Potential energy is defined as the ability to do work. Water potential is important to any process where soil water moves such as infiltration and redistribution within the soil, or the removal of water from the soil by evaporation or plant uptake. The absolute potential energy of an object cannot be measured. However, differences or changes in potential energy can be measured. The difference in potential energy between the rock found at the bottom of the hill and the rock at the top of the hill can be measured.