1. Management of water scarcity through micro irrigation
Università degli Studi di Firenze
Dipartimento di Ingegneria Agraria e Forestale
Management of water scarcity
through micro irrigation
Graziano Ghinassi – ITAL-ICID
5th Asian Regional Conference - Special session on Micro irrigation New Delhi, December 8th, 2009

2. Goals of modern on-farm irrigation
Attention to water and energy (efficient use of the resources)
Low (minimal) impact on environment
Economic sustainability of farmer’s activity

3. Micro irrigation has the potential to achieve these goals
Irrigation system should be:
-selected according to performance and economic criteria (equipment quality, market price, …)
well designed and assembled
managed properly (i.e., working pressure, lateral length, …)

4. Farmers and micro irrigation
Common idea: micro=water and energy saving per se
Inaccurate design
Modifications to the original design
Poor system maintenance
Unfamiliar performance
Exceeding equipment technical lifetime
Complex scheduling

5. Farmers and micro irrigation
Farmers’ self-evaluation about on-farm system and practice management degree (S.E.Agr.I.T. research project):
LOW: 7%;
FAIR: 79%;
GOOD: 14%.
General excess of irrigation water (up to 160%)

6. Test and design of drip lines and system units
Ve.Pro.L.G.s 2008
Test and design of drip lines and system units

7. Test and design of drip lines and system units
Ve.Pro.L.G.s 2008
Test and design of drip lines and system units

8. SOFTWARE DATABASE
Ve.Pro.L.G.s 2008 is a user-friendly application software created by the National Irrigation Laboratory of the University of Pisa (Italy) and supported by ARSIA Regione Toscana.
Equipped with the characteristics of about 70 drip line models, measured according to standardized laboratory test.

9. Use: test existing drip systems, compare options for
Use: test existing drip systems, compare options for rehabilitation or new design, based on set performance and cost (water and energy)
Input: data describing specific situations (type and position of manifold, drip lines length, field slopes, seasonal irrigation water supply, pressure at the inlet, etc..), costs (dripline, energy, …) and constraints (dripline lifetime, …)
Output: driplines matching farmer requirements

10. Test on annual crops

11. Test on existing drip line - Annual crop
Test on drip line
Design EU
Test on existing drip line - Annual crop

12. Test on existing drip sector - Annual crop
Test on drip sector
Lay flat
Design EU
Test on existing drip sector - Annual crop

13. Test and improvement on perennial crops

14. Seasonal irrigation supply
Field shape
Field characteristics - Vineyard
Field area
Field slopes
In-row plant spacing
Seasonal irrigation supply

15. Manifold characteristics - Vineyard
Manifold type
Monolateral
Bilateral
Manifold characteristics - Vineyard
Double
Manifold feed
Central
Left
Right
Driplines spacing

16. Test on existing drip line - Vineyard
Test on dripline
Test on existing drip line - Vineyard
Discharge evaluation
Actual working pressure

17. Test on existing drip line - Vineyard
Design EU
Test on existing drip line - Vineyard
Discharge along the lateral
Inlet
End

18. Test on existing drip line - Vineyard
Design EU
Test on existing drip line - Vineyard
Pressure along the lateral
Inlet
End

19. Test on existing drip line - Vineyard
Design EU
Test on existing drip line - Vineyard
Pressure along the lateral
Inlet
End

20. Search for optimal pressure and EU
New option on existing drip line - Vineyard

21. Search for optimal pressure and EU
Optimization of pressure at the inlet and EU
New option on existing drip line - Vineyard

22. New option on existing drip line - Vineyard
Pressure along the lateral
Inlet
End

23. New option on existing drip line - Vineyard
Optimal pressure at the inlet
New option on existing drip line - Vineyard
Pressure along the lateral
Inlet
End

24. New option on existing drip line - Vineyard
Optimal pressure at the inlet
New option on existing drip line - Vineyard
Pressure along the lateral
Inlet
End

25. Test on new option on existing drip line - Vineyard
Discharge along the lateral
Inlet
End

26. Case study

27. Annual crops (average values)
Central Italy

28. Measured EU in some drip systems
System n.

29. Water saving allowed by careful system maintenance
(estimated by Ve.Pro.L.G./s 2008)

30. Water saving allowed by careful system maintenance and Ve. Pro. L. G
Water saving allowed by careful system maintenance and Ve.Pro.L.G./s 2008 supported design

31. Apple orchard
Central Italy

32. Actual operating conditions
-Lateral: LDPE PN6 Ø 20 mm
-0.75 m spacing self-compensating emitters
-4 l/h nominal discharge
200 kPa max inlet pressure
100 to 130 m length
4% field slope
Measured EU: 58%
Potential EU (estimated by Ve.Pro.L.G.s)=93.3%

33. Search for EU best options

34. Search for EU best options

35. Search for EU under given pressure (50 kPa)

36. Search for EU under given pressure (50 kPa)

37. Search for EU under given pressure (50 kPa)

38. Conclusions Farmers wish for correct resources management
The way drip systems operate is unsuitable to proper irrigation practice in many cases
Users can play an important role in improving system performance
Ve.Pro.L.G.s 2008 software is an effective tool

39. http:/risorseidriche.arsia.toscana.it/
Free download

40. Thank you!