Irrigation of Fruit Trees – Established Orchard Sam Birrell, Netafim Agronomist International Pink...
Transcript of Irrigation of Fruit Trees – Established Orchard Sam Birrell, Netafim Agronomist International Pink...
Irrigation of Fruit Trees – Established Orchard
Sam Birrell, Netafim Agronomist
International Pink Lady Alliance Workshop, Chile
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AGENDAWater Budgets
Evapotranspiration
Crop Co-efficient
Crop Water Use
Irrigation Scheduling
When Do I Irrigate?
Monitor
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Water Budgets
Goodwin, Victorian DPI
Evapotranspiration (ETo)
Crop Co-efficient
FAO
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Crop Co-efficient
Kcb = Crop Co-efficientETo = Evapotranspiration
EAS = Effective area of shade
Crop Water Use
Goodwin et al
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Crop Water Use
Crop Co-efficient
Crop Water Use
Kcb = Crop Co-efficientETo = Evapotranspiration
EAS = Effective area of shade
1.3 X 0.4 = 0.52
0.52 X 8(mm) = 4.16 (mm)
Irrigation Scheduling
Run Time: How Long?
When do I irrigate ?
Drippers wet approximately 1/3 of the area ( W.A. )
Water contained in a 50 cm root zone ( R.Z. )
=RAW X R.Z. X W.A
=.3 X 50 X .33
= 4.9 mm
Moisture contained within the root zone or RAW of partial coverage irrigation system
When do I irrigate ?
System application rate System Application = emitter flow rate row spacing X emitter spacing
If Row spacing = 6 M Emitter output = 2.3 L/H Emitter spacing = 0.5 M 2.3 System Application = 6 X 0.5
= 0.76 mm/H
When do I irrigate ?
Run Time
Water used by the plant– = 4.9 mm
System application rate– = 0.76mm / H
No. hours to irrigate = 4.9 / 0.76 = 6.5 hours
When do I irrigate ?
Et
X
Kc
Month S O N D J F M A
Monthly Et 72 112 141 170 189 165 130 78
Crop Coefficient Kc .21 .21 .5 .6 .6 .57 .55 .5
Daily water use mm 0.5 0.75 2.3 3.3 3.6 3.3 2.3 1.3
Period between irrigations = RAW / Daily water use = 4.9 / 3.3 = 1.4 days ( every day )
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Monitor Moisture Probes
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Monitor
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Monitor
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Miscellaneous
Sub surface drip
THANK YOU