3. Introduction
• China, India, U.S.A : biggest irrigators
• 70 % grain in China and 50 % grain in India produced through
irrigation
• Worldwide, about 270 million ha lands are irrigated while in
India about 60 million ha lands are irrigated
• 69 % of global water used for agriculture purposes, 21 % for
industrial purposes and 10 % for residential use
• In developing countries the proportion of water going to
irrigation is higher, about 75-85% of total use
4. Definition
• Irrigation: artificial application of water to soil for proper plant
growth and crop production (Israelsen, 1950)
• Efficiency: quantify the relative output obtainable from a given input
• Irrigation efficiency: volume of water required for consumptive use
by the crop for its growth to the volume of water delivered from the
source
• Irrigation efficiency
Irrigation system performance
Uniformity of water application
Response of crop to irrigation
6. Irrigation system performance
• Conveyance efficiency
Ec = (Vf / Vt) x 100
• Application efficiency
Ea = (Vs / Vf) x 100
• Storage efficiency
Es = [Vs / (Vfc – Va)] x 100
Where
Vf = Volume of irrigation water that reaches the farm or field
Vt = Volume of irrigation of water diverted from the water source
Vs = Volume of irrigation water stored in the root zone
Vfc = Volume capacity at field capacity in the crop root zone
Va = Volume of water in the root zone prior to an irrigation event
7. Cont…
• Overall irrigation efficiency
Eo = (Ec x Ea x Es ) x100
• Effective irrigation efficiency
Ee = [Eo + (FR) x (1 - Ea)] x100
Where
FR = fraction of surface runoff , seepage, and deep percolation that is recovered
8. Uniformity of water application
• Christiansen’s Uniformity Coefficient (Sprinkler irrigation Systems)
Cu = [1- (Ʃ|X1 – XM|) / ƩX1] x 100
• Emission uniformity (Micro irrigation System)
EU = [1- 1.27 (Cvm)] n-1/2 (qmin/qavg) x 100
Where
X1 = measured depth water in equally spaced catch cans on a grid arrangement
XM = mean depth of water of the catch in all cans
Cvm = manufacturer’s coefficient of uniformity
n = number of emitters per plant
qmin = minimum discharge rate at minimum system pressure
qavg = average emitter dicharge rate
10. Uniformity of water application in the field
Uniform and efficientUniform and inefficient
11. Crop response to irrigation
• Crop water use efficiency
CWUE = Yg / ET
• Transpiration ratio (dry matter basis)
TR = ET / Yg
• Irrigation water use efficiency
IWUE = Yg / IR
Where
Yg = Economic yield
ET = crop water use
IR = irrigation water applied
13. Reasons for poor irrigation efficiency
• Non-stop flow of water to the field when the
amount of water needed has been delivered
• Absence of volumetric supply of water from the
water source to the field
• Non measurable soil moisture level at the time of
irrigation
14. Cont…
• Improper field levelling which cause poor water
distribution across the field
• Excessive slopes which cause high runoff losses
• Application of water not based on intake
characteristics of the soil
15. Improving irrigation efficiency
• Less stress on water resources, less losses of water
and nutrients to groundwater and surface water
resources
• Minimise irrigation inputs while continuing to
improve production and overall profits
• Allow a greater area to be irrigated with a given
volume of water
16. Cont…
• Modernization of Irrigation Projects
• Promotion of Efficient Irrigation Practices
• Promotion of Micro‐Irrigation Systems
20. Improving on-farm irrigation efficiency through deficit
irrigation
Deficit irrigation
An irrigation practice where the applied water is less than the amount of
water required for optimum plant growth
Way of maximizing water use efficiency (WUE) for higher yields per unit
of irrigation water applied
Samani et al. (2005)
21. Irrigation efficiency for Alfalfa crop
Field Soil type ET
(cm)
Irrigation
efficiency
(%)
Applied
water (cm)
A-1 Loam 172 98 175.5
A-1 Loam 148 94 157.5
A-1 Loam 149 96 155.2
A-2 Clay 186 87 213.8
A-2 Clay 167 89 187.6
A-2 Clay 152 95 160
22. Field Soil type ET
(cm)
Irrigation
efficiency (%)
Applied water
(cm)
B-1 Sand 92.5 94 98.4
B-1 Sand 138 93 148.4
B-1 Sand 82.4 93 88.6
Field Soil type ET
(cm)
Irrigation
efficiency (%)
Applied water
(cm)
C-1 Sand 77.2 96 80.42
C-1 Sand 64.9 94 69
C-1 Sand 89 94 94.7
Irrigation efficiency for cotton crop
Irrigation efficiency for pecan crop
23. Comparison between irrigation efficiencies for different crops
Field Soil
type
Crop ET (cm) Irrigation
efficiency
from
chloride
method (%)
Irrigation
efficiency
from
measured
water (%)
Applied
water
(cm)
G-1 Loamy
sand
Alfalfa 163.6 91 93 176
G-2 Sandy
loam
Alfalfa 91 83 73.4 124
H-1 Loam Pecan 77 92 83 93
K-1 Loam Pecan 107.5 98 88 122
L-1 Loam Cotton 81 96 89 91
25. Field efficiency of sprinkler irrigation methods
Irrigation
method
Field efficiency
(%)
Attainable Range Average
Periodic move 80 60-85 75
Side roll 80 60-85 75
Moving big gun 75 55-75 65
Centre pivot
LEPA 98 80-98 95
26. Field efficiency of different drip irrigation methods
Irrigation
method
Field efficiency
(%)
Attainable Range Average
Surface drip 95 70-95 85
Subsurface drip 95 75-95 90
Micro spray 95 70-95 85
27. Effect of pulse drip irrigation on yield and water use efficiency of
potato crop
Pulse irrigation
practice of irrigating for a short period then waiting for another
short period, and repeating this on-off cycle until the entire
irrigation water is applied
Pulse drip irrigation is a recent concept where small frequent
irrigation applications are applied to saturate the soil and meet
the plant water requirements
Bakeer et al. (2009)
28. Effect of pulse surface drip irrigation on application efficiency
29. Effect of pulse subsurface drip irrigation on application efficiency
30. Conclusions
• High on-farm irrigation efficiency (83-98 %) under deficit irrigation
can be achieved through laser leveled field and proper irrigation
scheduling
• Efficiency of drip irrigation system can be enhanced up to 99 %
through pulse drip irrigation
• Irrigation efficiency of furrow, border and basin irrigation in USA
varies from 65 %, 65 % and 85 % by adopting proper design of
these methods. Therefore, there is scope to improve the irrigation
efficiency in india by adopting similar approaches
31. The success of any Irrigation Technology
needs people
Who design & build it
Who live it
Sleep it
Dream it
Believe it
and build great future plans for it
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