CONSUMPTIVE USE Quantity of water require by plant to meet to meet it’s

evapouration-transpiration & to meet metabolic activities .

C.U = E +T +𝑊𝑚

>99% <1%

~ E+T C.U =consumptive use

𝑊𝑚=Water require for metabolic process

E= evapouration

T=evapouration13

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

Necessity of Consumptive use of water

Plane the crop pattern for a particular locality depending upon

availability of water .

Require to design a irrigation project .

Require to determine the quantity of water to be released from

reservoir or irrigation project .

In kharif season CU is less as compered to rabi season .

14CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

Factor affecting consumptive use

Climatic

Crop

Soil

Management

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

:1 . CLIMATIC FACTOR

a) Radiation

b) Temperature

c) Humidity

d) Wind velocity

e) Rainfall

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

CROP FACTOR

No. &size ofstomata

Opening &closing of stomata

Plant architecture &planting pattern

Stages ofgrowth

Rooting depth&pattern

Duration of thecrop

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

SOILFACTOR

Water holdingcapacity

Soil waterdepthInfiltrationrate

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

MANAGEMENT FACTOR

Time ofsowing

MulchingFertilizerapplication

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL

CONSUMPTIVE USE EXPRESSEDAS

Daily consumptive use: Total amount of 𝐻2O used in ET & metabolic

activities by crop during a single day .

Expressed in – mm/day or cm/day

Seasonal consumptive use: Total amount of 𝐻2O used in ET &

metabolic activities by crop during it’s total growing season .

Expressed in- mm/season or cm/season

Peak period of consumptive use :The average daily 𝐻2O use rate

in term of ET & metabolic activities during highest CU period

of season .

CE8603 – IRRIGATION ENGINEERING/V.PRIYA/AP/CIVIL