The method widely used in India for the computation of consumptive use is:
(c) Blaney-Criddle equation
Explanation:
In India, the Blaney-Criddle equation is commonly used for estimating the consumptive use (or evapotranspiration) of crops. This method is particularly suitable for regions where detailed climatic data (like radiation and wind speed) may not be readily available, but temperature and daylight hours are. It provides a relatively simple way to estimate the water requirements for crops, making it widely used in agricultural planning.
Other methods like the Penman’s equation and Hargreaves–Christiansen equation are more accurate but require more comprehensive meteorological data and are not as commonly applied for routine calculations in India. The Tanks and lysimeter method involves direct measurement of evapotranspiration but is more experimental and less commonly used for practical applications in the field.
Thus, the Blaney-Criddle equation is the most widely adopted method for determining consumptive use in India.