Question

The ratio of the quantity of water stored in the root zone of the crops to the quantity of water actually delivered in the field is
1. water conveyance efficiency
2. Water application efficiency
3. Water use efficiency
4. None of the above

Answer 1

Correct Answer - Option 2 : Water application efficiency

Explanation:

Irrigation Efficiency:

It is defined as the ratio of water available for use to water applied is defined as Irrigation Efficiency.

Various types of efficiency are given below,

(1).Water Conveyance Efficiency(n_c):

It is defined as the ratio of the quantity of water delivered to the field OR the irrigated land to the quantity of water diverted into the canal system from the river of Reservoir.

\({n_c} = \;\frac{{{W_f}}}{{{W_r}}}\; \times 100\) where

W_f = water delivered to the field 

W_r =water delivered to the canal system from the river.

(2).Water Application Efficiency(n_a):

It is defined as the ratio of the quantity of water stored in the root zone of the plants to the quantity of water delivered to the field.

\({n_{a\;}} = \;\frac{{{W_s}}}{{{W_f}}} \times 100\) Where,

W_S = The water stored in the root zone,

W_f = the quantity of water delivered to the field.

(3).Water Use Efficiency(n_u):

It is defined as the quantity of water used beneficially including the water required for leaching to the quantity of water delivered.

\({n_u} = \;\frac{{{W_u}}}{{{W_f}\;}} \times 100\), Where,

Wu =  The quantity of water used beneficially.

W_f= The quantity of water delivered to the field.

• The water quantity efficiency accounts for the water losses which occur in a conveyance from the point of diversion into the canal system to the fields.
• The presence of excess salts in the soil would require that water storage efficiency should be high in order to keep the salts washed out of the soil.