Precision Irrigation Management

1. Precision Irrigation
Management
Siddu Malakannavar
Agronomy

3. S.
N
Region Irrigated
area
(m ha)
Irrigated
area
(%)
1 Africa 14.74 4.9
2 America 46.51 15.6
3 Asia 214.41 71.7
4 Europe 23.38 7.8
Total 299.04 100
 20 % of the world's croplands are irrigated;
 Produce 40 % of the global harvest,
 irrigation multiplies yields of most crops by 2 to 5
times.
Source: ICID (2014-1
 Irrigated area :62 M ha
 Area under sprinkler irrigation : 3.04 M ha
 Area under drip irrigation :1.87 M ha
 Micro irrigation(DI+SI) :4.94 M ha
 % Micro-irrigated area :8.1%
India

4. Per Capita Water Availability in various
countries (000 Cu. M.)
S.
No.
Country Water Availability (000 Cu. M.)
1975 2000 2025
1. China 3.0 2.2 1.9
2. India 3.1 1.9 1.4
3. Pakistan 5.6 2.7 1.0
4. U. K. 1.3 1.2 1.2
5. U. S. A. 11.3 8.9 7.6
6. Bangladesh 15.8 9.4 6.8
7. Nepal 16.4 8.8 5.5

5. Deep percolation
Run off
Evaporation from soil surface
Evaporation
Wind drift
Transpiration from vegetation
Infiltration
Decreased efficiency in conventional irrigation

6. Also called site-specific irrigation
◦ A tool of precision farming that involves the
delivery of irrigation water in optimum
amount over an entire field
◦ New generation of innovative systems to
monitor and control soil moisture deficiency
and irrigation

7.  Driving forces
◦ Excessive water application could contribute to
surface water runoff or leaching of nutrients and
chemicals to groundwater
◦ Precision irrigation systems would have the
ability to apply water directly where it is needed,
therefore saving water and preventing excessive
water runoff and leaching

8.  Internal reasons
◦ Very few fields are uniform, the need for irrigation
may differ between different zones of a particular
field
◦ Most currently used irrigation systems apply water
at constant rates, therefore some areas of a field
may receive too much water and other areas of a
field may not receive enough water

9.  Irrigation scheduling is the heart of precision
irrigation, which simply knows where, when to
irrigate and how much irrigation water to apply
 An effective irrigation schedule helps to maximize
profit while minimizing water and energy use

10.  Three ways
◦ Measuring Soil-Water
◦ Checkbook Method
◦ Remote sensing

11.  Measuring soil water
◦ Quantitative methods
 Neutron Scatter
 Di-electric Constant Methods
 Gravimetric Soil Sampling
◦ Qualitative methods
 Tensiometers
 Porous Blocks

12. ◦ The check-book method is an accounting approach for
estimating how much soil-water remains in the effective root
zone based on water inputs and outputs (like a daily balance
on a bank account based on deposits and withdrawals)
◦ Irrigation is scheduled when the soil-water content in the
effective root zone is near the allowable depletion volume,
otherwise irrigation should be delayed.
Remote sensing
 Satellite image and air photo
 Infrared thermometry is a more recently developed
technique to determine irrigation timing based on
plant canopy temperature rather than soil moisture

13.  Water resources are unlimited.
 Water is available at no cost.
 More irrigation – more yield.
 Head-reach farmers-right to use any quantity of water.
 Underground aquifiers supply limitless water.
 Supply of irrigation water to the farmers is the duty
of the Government.
Misconceptions about water Resources

14. ➢ Simple and easy to install and configure.
➢ Saving energy and resources, so that it can be utilized in proper way and
amount.
➢ Farmers would be able to smear the right amount of water at the right time
by automating farm or nursery irrigation.
➢ Avoiding irrigation at the wrong time of day, reduce runoff from
overwatering saturated soils which will improve crop performance.
➢ Automated irrigation system uses valves to turn motor ON and OFF.
Motors can be automated easily by using controllers and no need of labor
to turn motor ON and OFF.
➢ It is precise method for irrigation and a valuable tool for accurate soil
moisture control in highly specialized greenhouse vegetable production.
➢ It is time saving, the human error elimination in adjusting available soil
moisture levels.

15.  Discovered in Israel.
 Drip irrigation is a micro irrigation method
in which the rate of water application is
very low and without any pressure. i.e.,
drop by drop.
 Discharge rate of water per dripper is
generally ranges 1-4 liters/hours.
 Water flows from the emission points
through the soil by capillarity and gravity. 15

16. 16
Sr.
No.
Country Irrigated
area
(M ha)
Area under Micro-irrigation (M ha)
Sprinkler % Drip % Total %
1 Israel 0.23 0.058 25 0.170 74 0.228 99
2 France 1.58 1.42 90 0.103 7 1.523 97
3 Russia 4.45 3.96 89 0.200 4 4.160 93
4 Saudi Arabia 1.17 0.75 64 0.198 17 0.948 81
5 Spain 3.28 0.89 27 1.172 36 2.062 63
6 USA 21.3 9.80 46 1.209 6 11.01 52
7 South Africa 1.49 0.60 40 0.178 12 0.778 52
8 Brazil 3.44 1.20 35 0.378 11 1.578 46
9 India 60.0 1.71 3 0.850 1 2.300 4
TABLE: COUNTRIES HAVING SIGNIFICANT AREAS UNDER MICRO-IRRIGATION

17. 17
S.No State Up to 2005-06 (ha) 2006-07 (ha) Total (ha)
1 Maharashtra 219696 51597 271293
2 Andhra Pradesh 152227 66258 218485
3 Karnataka 114304 21679 135983
4 Tamil Nadu 116665 12241 128906
5 Gujarat 16686 38314 55000
6 Rajasthan 10025 2653 12678
7 Kerala 10559 848 11407
8 Madhya Pradesh 6483 2751 9234
9 Uttar Pradesh 4609 1633 6242
10 Punjab 4262 1141 5403
11 Haryana 4219 1068 5287
12 Orissa 2036 429 2465
13 Chattisgarh 1979 0 1979
14 Goa 740 8 748
Total 664490 200620 865110
Table : STATUS OF DRIP IRRIGATION COVERAGE IN INDIA

18. A layout of drip irrigation system
18

19. Benefits
of Drip
Irrigation
Reduce
Energy
Use
Reduce
Labor
Costs
Reduce
Fertilize
r Use
Reduce
Pesticide
Use
Improve the
Environmen
t
Improve
Flexibilit
y
Reduce
Risk
Improve
Crop
Quality
and
Uniformity
Increase
Yields
Maximize
Water
Use
Efficiency
Reduce
Energy
Use
Reduce
Labor
Costs
Reduce
Fertilize
r Use
Reduce
Pesticide
Use
Improve the
Environment
Improve
Flexibility
Reduce
Risk
Increase
Yields
Income
Quality
Uniformity
Water
Energy
Labor
Fertilizer
Pesticide
Benefits of Drip Irrigation

20. Drip method Flood method
Water saving
High, between 40 and 90 % Less. High rates of
evaporation, surface run off
and percolation
Irrigation efficiency 80 – 90 % 30 - 50 %
Suitable water
Even saline water can be
used
Only normal water can be
used
Efficiency of fertilizer use
Very high since supply is
regulated
Heavy losses due to
leaching
Water logging
nil high
Yield increase 20 - 50% higher than flood
method
Less compared to drip

21. Method
Yield
(t/ha)
WU
(cm)
WUE % saving
Raingun 150 171 08.7 21.7
Overhead 157 159 09.8 27.0
Micro 154 152 10.1 30.4
Micro jet 153 149 10.2 31.7
Drip 162 111 14.5 49.2
Surface 134 219 06.1 -
CD(P=0.05) 7.3
Rahuri, Maharashtra AICRP on Irrig. Water
management report 2011--12

22. 22
MICRO-SPRINKLER IRRIGATION
In this system small sprinkler like devices called
micro-sprinkler, spray water over soil surface in the
root zone at low pressure.

24. Sprinkler system layout

25. Sprinkler system components

26. Sprinkler irrigation in maize and lettuce

29. 29
• Micro sprinklers are low capacity water emitters, sprinkler in type,
but smaller in size than the conventional sprinklers and with flow
rates up to 250 l/hr.
• They are placed on a relatively close rectangular or triangular spacing
for the maximum overlap to irrigate potato, carrot, leafy vegetables,
groundnut, onion and other densely planted field crops.
• This method is reliable, highly efficient, and easy to apply, operate
and handle.
• The system is a seasonal, low pressure, micro-irrigation solid
installation which can be easily placed in the field and quickly
removed (collected) at the end of the season.
• It have large orifices cover large area in short time.
• It minimize the hazard of clogging of emitters by way of larger nozzle
orifices.
•
MICRO SPRINKLER

30. 30
Micro sprinkler irrigation under control condition

31. 31
MICRO-JET IRRIGATION
Merits-
The water discharge rate of the jets
(liter per hour) which is much higher
than that of the drippers.
The individual micro-jet is able to
wet larger area of ground than a
dripper.
It minimize the hazard of clogging
of emitters by way of larger nozzles.
It has lower application rates.
In micro-jet irrigation system water is ejected as fine jet that
fan out from a series of nozzles over plant canopy and soil
surface at a pressure of nearly one bar.

32. Operating pressure: 1-2 bars
 Flow rate: 35-250 litres/hr
 Wetting diameter: 3-6 m
 Precipitation rate: 2-20 mm/hr
Performance Characteristics of Mirco-Jet
Ref: Pressurized Irrigation Techniques By FAO

33. 33

34. 34
Subsurface Drip irrigation

35. Subsurface drip irrigation (SSDI) is advancement over surface
drip irrigation.
Defined as application of water below the soil surface through
the emitters, with discharge rates generally in the same range as
surface drip irrigation
Indicates lateral placement below soil surface.
Subsurface Drip Irrigation

36. Reduced evaporation loss
Precise placement of water and chemicals
More efficient water and chemical use
Enhanced plant growth, crop yield and quality
Less interference with cultural operations
Reduced damage due to weed, pest and diseases
Reduced exposure of irrigation equipment to damage
No soil crusting due to irrigation
Advantages of SSDI over surface drip irrigation

37. 37
Subsurface drip irrigation in cotton

38. particular SSDF CM of
cultivation
CD
(P=0.05)
Individual cane weight(kg) 1.52 1.27 0.15
Cane yield(t/ha) 112.7 87.5 3.60
% yield increase 29.0 - -
Total water use(mm) 1714 2456 -
% water saving by SSDF 30.2 - -
WUE(kg/ha-mm) 65.8 35.6 -
Cost of cultivation(Rs./ha) 83,562 81,438 -
Gross income(RS./ha) 2,25,353 1,75,000 -
Benefit-cost ratio 2.69 2.15 -
38
Productivity , WUE and economics of sugarcane under
subsurface drip Fertigation
Pandian et al., (2010).Tamil Nadu

39. Pre-requisites for precision irrigation in
agriculture
1. Ground water monitoring sensors
2. Irrigation water quality sensors
3. Water conveyance monitoring sensors
4. Canal maintenance sensors
5. Soil moisture sensors

40. 1. Ground water monitoring sensors
 Real time monitoring of ground water fluctuations
 Remote sensing based system

41. 2. Irrigation water quality sensors
 pH
 Electrical conductivity
 Turbidity (Sediments)
 SAR (Sodium absorption ratio)
 Boron
 Anions (Chlorine, Sulphate, Carbonates, Bicarbonates)
 Cations (Na, K)

42. 3. Water conveyance monitoring sensors

43. A. Soil based: Soil moisture
 Soil Water Content‐based soil moisture sensors (Capacitance, Neutron
Probe, Gypsum resistance, volumetric)
 Tension‐based soil moisture sensors (Tensiometers)
B. Plant based:
 Thermocouple / Temperature
 Water Potential Gradient
 Plant wilting system based
C. Weather based: Humidity and VPD
Irrigation water management sensors

46. IrriWise™
, IrriWise™ Manager continuously collects data from the field, enabling you to
view and analyze data in real time
Innovative wireless technology

47. Prospects of Sensors in Water Management

48. USA

50. B. Plant based:
 Thermocouple / Temperature
 Water Potential gradient (SPAC)
 Plant wilting based

51.  Leaf temperature based
 Sold Over 7,00,000 machines worldwide
 Irrigate 70 million acres worldwide
Thermocouple / Temperature

52. No
Sensors
Sensor-
Based
Irrigation
Annualized Revenue $66,297.36 $ 145,505.64
Annualized Production Costs $30,539.11 $50,039.93
Annualized Sensor System Cost $ 0.00 $3,755.24
Annualized Profit $35,758.24 $91,710.47
Annualized Profit per Square Foot $1.79 $ 4.59
Percent Change from Base Case +156%
The system payback was less than one month!

53. Save Water
Save energy
and…
save life