WATER REQUIREMENTS OF CROPS

BY: T.HARISH

IntroductionFor the design of water

harvesting systems, it is necessary to assess the water requirement of the crop intended to be grown.

There have been various methods developed to determine the water requirement for specific plants. 

Factors influencing crop water requirementsInfluence of climateInfluence of crop type on crop

water needsMethod of Application of waterWater tableGround SlopeType of soil

Influence of climateIn hot climate the evaporation

loss is more and hence the water requirement will be more and vice versa.

A certain crop grown in a sunny and hot climate needs more water per day than the same crop grown in a cloudy and cooler climate. 

Influence of climate

Influence of crop type on crop water needsThe influence of the crop type on

the crop water need is important in two ways.

1)  The crop type has an influence on the daily water needs of a fully grown crop

2) The crop type has an influence on the duration of the total growing season of the crop

water needed for different crops

Method of Application of waterIn sprinkler method less water is

required as it just moist the soil like rainwater whereas in flood more water is required.

Drip (or micro) irrigation can be the most water-efficient method of irrigation, if managed properly, since evaporation and runoff are minimized.

Drip (or micro) irrigation

Water tableIf the water table is nearer to the

ground surface, the water requirement will be less & vice versa.

Water table

Ground SlopeIf the slope of the ground is steep

the water requirement will be more due to less absorption time for the soil.

Ground Slope

Type of soilIn sandy soil water percolates

easily so water required is more. While in clayey soils water requirement is less.