The saturation capacity, field capacity and permanent wilting point of a soil are 47%, 27% and 14% respectively. The available moisture for the crops grown in the soil is:
The saturation capacity, field capacity and permanent wilting point of soil are 47%, 27% and 14% respectively. The available moisture for the crops grown in the soil is 13%.
Readily available moisture-
(i) It is that portion of the available moisture which is most easily extracted by the plants, and is approximately 75 to 80% of the available moisture.
(i) Immediately after a rain or irrigation water application, when all the gravity water has drained down to the water table, a certain amount of water is retained on the surfaces of soil grains by molecular attraction and by loose chemical bonds. This water cannot be easily drained under gravity and this is called field capacity.
Permanent wilting point-
(i) It is the water content at which a plant can no longer extract sufficient water for its growth, and wilts up.
Soil moisture (water) depletion (deficit)
The difference between field capacity and the actual soil moisture in the root zone soil at any given time. It is the amount of water required to bring the soil in the root zone to field capacity; the amount of water required to fill the plant root zone to field capacity
Available Moisture = Field capacity – Permanent within point