Consumptive use of water

Write a short note on Consumptive use of water

Solution:-

Consumptive use of water:

•  It is the amount of water required by a crop in transpiration i.e. growth of plant tissues and the water lost from the surrounding soil and from the leaves as evaporation. It is also referred to as evapotranspiration.

•  The value of consumptive use of water varies from crop to crop and from soil to soil. Also it may differ for the same crop at different times of a year.

•  Consumptive use is useful in assessing the irrigation requirement for a crop.

•  The factors which affect the consumptive use of crop are temperature, humidity, wing velocity, atmospheric pressure etc.

•  Blaney – Criddle equation is the most commonly used expression for estimating the consumptive water requirement of a crop in a area which is given by:

Cu= kp/40[1.8t+32]

Where Cu = monthly consumptive use (in cm)
k = Crop factor which is determined experimentally for each crop under the given environmental conditions
t= Mean monthly temperature (in ∘C)
p = Monthly percentage of annual day light hours for the period under consideration