Soil moisture tension

• Soil moisture tension is the measurement of how strongly water is held in the soil. Water is held in the soil by capillary forces as well as the attraction of the water molecule to itself and to electrically charged clay particles.
• Soil moisture tension is measured in units of pressure (centibars or kilopascals).
• Soil moisture tension is negative pressure and commonly expressed in units of bars. Thus, as soil moisture tension increases (the soil water pressure becomes more negative), the amount of energy exerted by a plant to remove the water from the soil must also increase.
• Simply, Soil moisture tension is the ease to which the plant root has to work to extract water from the soil.
• It is the measure of the tenacity with which water is retained in the soil and is the force per unit area that must be exerted to extract the water from the soil.
• It is also known by the means as capillary potential, capillary tension, soil pull, force of suction etc. It is expressed in atmosphere.
• Soil moisture tension is governed by two factors: Soil moisture content and the salt contents.