Submergence Potential (ys)

• Submergence potential is positive hydrostatic pressure which is developed due to weight of water in saturated soils and aquifers.
• This potential is operational only for the saturated zones below the water table.

Quantitative Expression of Soil Water Potential

1. Energy per unit mass= Erg/gm or Jule/Kg
2. Energy per unit volume = dynes/cm2 or Newton/m2: the energy per unit volume yields the dimensions of pressure (for example, the energy can be expressed the product of pressure by volume, so the ratio of energy to volume gives a pressure). This equivalent pressure can be measured in terms of dynes per square centimetres or newton per square meters, bars or pascals or atmospheres.
3. Energy per unit weight = Hydraulic head: it is expressed in hydraulic head which is the height of a liquid column corresponding to given pressure. For example, Pressure of 1 atm. is equivalent to a vertical column of water i.e. wt. of liquid 1033cm and mercury wt of 76 cm. The total potential head, gravitational head and pressure potential head are usually expressed in centimetres of water.