CHAPTER VI: PRINCIPLES OF DRIP MICRO OR TRICKLE IRRIGATION

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CHAPTER VIPRINCIPLES OF DRIP/ MICRO OR TRICKLE
IRRIGATION
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(No Transcript)
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• INTRODUCTION
• The demand of available water is decreasing
  throughout the world.
• The drip irrigation is one of the most efficient
  irrigation systems.
• The drip irrigation is a slow and frequent
  application of water to the soil by means of
  emitters or drippers located at specific
  locations throughout the lateral lines.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• HISTORY
• It is believed that the use of drip irrigation
  began in 1950, when an Israeli engineer observed
  a vigorous growth of a tree near a faucet
  (dripping water) compared to other trees in the
  field.
• The origin of drip irrigation is traced back to
  1860 A.D. in Germany, where a buried drip
  irrigation system was developed.
• The transfer of this technology in U.S.A. took
  place in 1913 A.D.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• HISTORY
• During 1920, perforated tubes were used in
  Germany.
• It was not until the development of the plastic
  tubes during and after World War II, when the
  drip irrigation became economically feasible and
  acceptable.
• The first drip irrigation system in Puerto Rico
  was installed in 1970.
• Today, acreage under drip irrigation for
  vegetables and fruits is approximately 40,000
  acres in Puerto Rico.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation Drip Irrigation Definition

• Drip irrigation also known as trickle irrigation
  or microirrigation is an irrigation method that
  applies water slowly to the roots of plants, by
  depositing the water either on the soil surface
  or directly to the root zone, through a network
  of valves, pipes, tubing, and emitters.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation The Water flow in drip irrigation

• 1. Continuously throughout the lateral
  
• line
• 2. From an emitter or dripper connected
• to the lateral line.
• 3. Through orifices perforated in the
• lateral line.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Efficient use of the water
• Reduces the direct losses by evaporation.
• 2. Does not cause wetting of the leaves.
• 3. Does not cause movement of drops of water by
  the effect of air.
• 4. It reduces consumption of water by the grass
  and weeds.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Efficient use of the water
• 5. It eliminates superficial drainage.
• 6. It allows to irrigate all the field until the
  edges.
• 7. It allows the irrigation to an exact depth.
• 8. It allows to irrigate greater land area with a
  specific amount of water.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Reaction of the plant
• 1. It increases the crop yield per unit
  (hectare-centimeter) of applied water.
• 2. It improves the crop quality.
• 3. It allows a uniform yield.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Environment of the root
• 1. It improves ventilation (aeration).
• 2. It increases quantity of available nutrients.
• 3. Creates a constant condition of water
  retention at low tension.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Control insects and diseases
• 1. It increases efficiency of the sprayings of
  insecticides and pesticides.
• 2. It reduces development of insects and diseases.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Agronomic practices and effects
• 1. The activities of the irrigation does not
  interfere with the activation of the crop, the
  plant protection and the harvesting.
• 2. It reduces intercultivation, since there is
  less growth of weeds, and soil compaction.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Agronomic practices and effects
• 3. Controls the erosion.
• 4. Applies fertilizers through the irrigation
  water.
• 5. Increases the work efficiency in fruit
  orchards, because the space between the rows is
  maintained dry.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Economic benefits
• 1. The cost is lower compared with other
  permanent irrigation systems.
• The cost of operation and maintenance is low. 
• The cost is high when the average row spacing is
  less than 3 meters.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ADVANTAGES
• Economic benefits
• 4. It can be used in uneven terrains.
• The water application efficiency is high. 
• Energy use per acre is reduced due to smaller
  diameter of pipes.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DISADVANTAGES
• It cannot adjust to all the specific crops, sites
  and objectives.
• The drippers are clogged easily with soil
  particles, algae or mineral salts.
• The rodents or insects can damage some components
  of the drip irrigation system.
• The soil moisture is limited, because it depends
  on the dripper, drippers spacing and soil type.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DISADVANTAGES
• 5. A more careful high technology management
  is needed compared to other irrigation systems.
• 6. The initial investment and annual costs
  are higher compared to other irrigation methods.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DRIP IRRIGATION SYSTEM
• Components
• The water source.
• The pump and the energy unit.
• The filtration system (See chapter VII).

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DRIP IRRIGATION SYSTEM
• Components
• The chemical injection system (See chapter X).
• The controls for the automation (See chapter
  VIII).
• The water distribution system.
• The drippers or emitters.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DRIP IRRIGATION SYSTEM
• Accessories for a drip irrigation system are
• Gate or ball valve
• Safety or check or one way valve
• Flushing valve
• Union
• Nipple
• Adapters

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DRIP IRRIGATION SYSTEM
• Accessories for a drip irrigation system are
• Reducers
• Tee
• Coupling
• Universal
• Elbow 
• Double union and cross

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 1 (a). Components for a typical drip/
  micro or trickle irrigation system.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 1 (b). Components for a typical drip/
  micro or trickle irrigation system.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• COMPONENTS IN FIGURE 1(b)
• Parts
• 1. Pump
• 2. Control
• 3. Safety valve
• 4. Water source
• 5. Fertilizer injector
• 6. Pressure gages
• 7. Primary Filter
• 8. Gate or ball valve

• 9. Main line
• 10. Secondary filter
• 11. Secondary line
• 12. Laterals or drip lines
• 13. Micro sprinklers or emitters or drippers
• 14. Solenoid valve

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE WATER SOURCE
• The water source can be a treated water, well
  water, open channel, rivers and lakes.
• The clean water is essential for the drip
  irrigation. 
• If water of poor quality is used, physical and
  chemical or biological agents can obstruct the
  emitters and drip laterals.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE WATER SOURCE
• The underground well water is generally of good
  quality.
• Almost all water sources contain bacteria and
  elements that nourish it.
• A good filtration system is needed to remove all
  the polluting agents that can obstruct or clog
  the drippers.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE PUMP
• It represents a significant part of a initial
  installation cost.
• It is necessary to acquire effective, reliable
  and low cost pump and a power unit.
• A centrifugal pump (Figure 2) is suitable for
  extracting water from superficial sources or
  shallow wells.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE PUMP
• The centrifugal pump is relatively cheap and
  efficient. 
• While selecting a pump, one should know total
  pressure in the system, operating pressure, total
  volume of water for irrigation and horsepower
  rating.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
lthttp//www.ext.nodak.edu/extpubs/ageng/irrigate/a
e1057w.htmgt
Figure 2 (a). Pumps.
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
lthttp//www.agric.nsw.gov.au/reader/pumps/e58.htmgt
Figure 2 (b). Pumps.
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
lthttp//www.goulds.com/product.asp?ID40MASTERID
5gt
Figure 2 (c). Pumps.
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• ENERGY OR POWER UNITS
• The electrical motors are preferable because of
  high overall efficiency, ease of automation,
  quiet operation and necessity of least
  maintenance.
• The gasoline or diesel engines can also be used.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION CONTROLS
• The volumetric valve
• or timing valve
• The volumetric valve measures volume of
  irrigation application and is necessary for
  proper management.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION CONTROLS
• The pressure gage
• The pressure gage measures water pressure in the
  drip irrigation system.
• It is especially useful for non compensating
  pressure drippers.
• The pressure gages on the upstream and downstream
  side of the filtering system indicates pressure
  loss that helps in flushing of filters.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 3. Pressure gage.

ltwww.rwc.co.uk/IMAGES/gage.jpggt
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION CONTROLS
• The pressure regulator or pressure relief valve
• The manual valves, the automatic metering valves,
  the semiautomatic valves and time controllers are
  recommended for the drip irrigation system.
• The automatic flow valves provide desired amount
  of irrigation in a specified time.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION CONTROLS
• The pressure regulator or pressure relief valve
• These also reduce pressure variations between the
  lateral lines in an uneven land.
• The combinations of pressure regulator and flow
  control valve are also available.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 4. Pressure regulator in the drip
  irrigation system.

Lateral line
Secondary line
Pressure controller
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION CONTROLS
• Air relief valve or vacuum breaker
• This valve removes air from the drip irrigation
  systems. 
• The suction or vacuum is developed when the
  irrigation system is shut off.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION CONTROLS
• Air relief valve or vacuum breaker
• This vacuum can obstruct the drippers if the
  dirty water or dust is suctioned into the
  system. 
• Vacuum breaker or air relief valve of one inch
  for each 25 gpm of flow is recommended. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 5. Air relief valve or vacuum breaker.

lthttp//www.rainbird.com/about/imagelibrary/drip/
index.htmgt
lthttp//www.jains.com/Control20and20safety20val
ves/jain20air20release20valvesgt
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE DRIPPER OR EMITTER
• The water emission devices (drippers or emitters
  or micro sprinklers) are unique in the drip
  irrigation system. 
• The drippers supply water through small orifices
  in small amounts near the plant. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE DRIPPER OR EMITTER
•  
• The pressure loss through the emitters must be
  sufficiently greater than the pressure difference
  due to land topography and friction losses in the
  system. 
• The orifice must be large enough to avoid serious
  obstructions. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE DRIPPER OR EMITTER
• There are two categories of drippers for
  installation in the field
• In-line emitters.
• On-line emitters.
• The in-line emitters are used in the green houses
  and for row crops such as vegetables and some
  fruit orchards.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE DRIPPER OR EMITTER
• The on-line drippers are suitable to flat lands
  to maintain acceptable uniformity of emitter
  flow.
• Micro tubes or spaghetti connected on the lateral
  line are used for fruit orchards, ornamentals and
  flower pots in the nursery (green house).

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 6 (a). Types of emitters.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 6 (a)
• In-line emitters.
• On-line emitters.
• Micro sprinklers.
• Micro tube (spaghetti).

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 6 (a)
• Compensating pressure emitter.
• Low pressure emitter lines.
• Biwall drip lines.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 6 (b). Types of emitters.

lthttp//homeharvest.com/dripirrigationemitters.htm
gt
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION DURATION
• The irrigation duration depends on the following
  factors
• 1. The plant water requirements in gallons.
• 2. Irrigation interval between each application
  and irrigation frequency.
• 3. Dripper flow rate and volume of water
  application.
• Soil and plant characteristics.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION DURATION
• Factors (Continued)
• The irrigation duration can be calculated as
  follows

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE CLOGGING AGENTS IN THE IRRIGATION WATER
• Depending on the water resource, the quality of
  water varies considerably depending on physical/
  chemical and biological composition, water demand
  and rainfall. 
• The clogging agents in the water can be of
  physical, chemical or biological nature.    

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE CLOGGING AGENTS IN THE IRRIGATION WATER
•   
• The physical clogging agents are sand, silt and
  clay. 
• The chemical clogging agents include minerals and
  salts in the water. 
• Many of these clogging may stimulate growth of
  microorganisms. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE FLUSHING OF SUBMAINS AND LATERALS
• The maintenance and flushing of the main,
  secondary and lateral lines are indispensable for
  the good operation of a drip irrigation system. 
• A good filtration system may catch larger size
  particles like clay and sand (see chapter VII).

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE FLUSHING OF SUBMAINS AND LATERALS
• The periodic flushing of lateral lines will
  reduce these obstructions. 
• The main and secondary lines must have a
  sufficient flow rate to allow flushing.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE FLUSHING OF SUBMAINS AND LATERALS
• The flushing time must be sufficient to allow all
  sediments out of the lines. 
• A regular program of inspection, maintenance and
  flushing helps to reduce clogging of the
  emitters. 
• The nature of the filtration system, the quality
  of the water and the experience of the operator
  will determine when it is necessary to flush the
  lines.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE FLUSHING OF SUBMAINS AND LATERALS
• The maintenance and flushing must be a routine
  procedure, if the drip irrigation system has been
  out of service. 
• This practice of maintenance reduces obstructions
  due to sediments in the lines and drippers. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE UNEVEN TERRAIN
• The unevenness of the agricultural land is an
  important design criteria. 
• The change in an elevation causes a pressure loss
  or gain. 
• In a leveled or almost leveled land, the lateral
  lines with drippers must run throughout crop
  row. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE UNEVEN TERRAIN
• In slopes, drip lines must follow the contour
  lines. 
• When the lateral lines in uneven field are
  designed, it is advisable to consider the
  advantage of the slope. 
• Thus the energy gain with the decrease in
  elevation is balanced.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE FRUIT ORCHARDS
• During dry periods, the fruit trees respond to
  the drip irrigation with good vegetative and
  fruit growth. 
• The quantity of fertilizers is reduced to about
  50 percent with fertigation.
• Generally in fruit orchards, drip irrigation
  system is installed permanently with the main and
  secondary lines buried.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE FRUIT ORCHARDS
• The lateral lines with drippers can be buried or
  left on the soil surface.
• In fruit orchards, the emitters are located
  within the shaded area of the tree.
• When a drip irrigation system for fruit trees is
  designed, more drippers are added as the tree
  grows.
• When installing the system, it is important to
  consider the life of the tree (10 to 20 years). 
  This is the main reason for installing (or
  burying) the mains and sub mains below the soil
  surface.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 7. Drip irrigation system in fruit
  orchards.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 7
• Emitter.
• Lateral line.
• Pattern of wetting zone.
• Leaf coverage.
• Trunk.
• Buried main line.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 7
• Do not allow flooding of the base of the trunk to
  avoid diseases.
• Move the emitter away from the tree trunk
  depending on the age of a tree.
• The emitter is near the trunk for the young tree.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 8. Drip irrigation system in small
  fruit orchards (wines).

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 8
• Continuous band of wetted zone.
• Lateral lines with emitters.
• Emitters.
• Secondary line or submains or lateral lines.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE VEGETABLE CROPS
• The drip irrigation system is more beneficial in
  vegetable crops that are planted in rows. 
• The emitters apply the desired amount of water
  throughout the row, and the row spaces are left
  dry. 
• The drip lines are placed on the soil surface
  along the rows of plants.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE VEGETABLE CROPS
• It can also be located few inches below the soil
  surface. 
• Generally, these lines of distribution are
  located perpendicular to the direction of the
  secondary main line.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 9. Drip irrigation system in vegetable
  crops.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 9
• Organic matter mulch.
• Soil surface.
• Plant.
• Emitter integrated in the line or in-line
  drippers.
• Filter.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Components in Figure 9
• Principal or main line.
• Secondary line or submain.
• Optional Gate valve.
• Connecting tube (or spaghetti).

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Drip irrigation in New Mexico vineyard, 2002, In
small fruit orchids
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION DISTRIBUTION SYSTEM
• The irrigation distribution includes pump house,
  main and sub mains, and drip lateral lines
  (Figure 1). 
• The water from the pump is distributed to the
  field through a main line. 

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• THE IRRIGATION DISTRIBUTION SYSTEM
• The secondary lines of smaller diameters take the
  water from the main line to the lateral lines.
  And the lateral lines supply the water to the
  drippers, which allow slow application to the
  plant.
• The main lines can be of high pressure PVC,
  galvanized iron, polyethylene or lay flats.  The
  main lines must be buried at least 0.6 meters (2
  feet) to avoid mechanical damage during the field
  operations.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
1

• SUBSURFACE DRIP IRRIGATION SYSTEM (SDI)
• Subsurface drip irrigation is a variation of
  traditional drip irrigation where the tubing and
  emitters are buried beneath the soil surface,
  rather than laid on the ground or suspended from
  wires.
• The products in SDI come in three basic
  configurations hard hose, drip tape and porous
  tubing.

1
Zoldoske, D.F., 2000. Subsurface Drip Irrigation
The Future of irrigation is underground. The
Western Chestnut Grower Association Inc., 3 (1)
6-7.
77
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
1

• SUBSURFACE DRIP IRRIGATION SYSTEM (SDI)
• Other design components of subsurface drip
  irrigation such as filtration and valving are
  very similar to those found in conventional drip
  application
• Water use requirements of subsurface drip may not
  differ significantly from conventional uses.
• The net difference between surface and subsurface
  drip systems in total requirements is small.

1
Zoldoske, D.F., 2000. Subsurface Drip Irrigation
The Future of irrigation is underground. The
Western Chestnut Grower Association Inc., 3 (1)
6-7.
78
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 10 (a). Subsurface drip irrigation system.

lthttp//www.microirrigationforum.com/new/gallery/s
disch.htmlgt
79
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 10 (b). Subsurface drip irrigation system.

lthttp//www.norweco.com/html/products/Drip.htmgt
80
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Figure 10 (c). Subsurface drip irrigation system.

lthttp//www2.dpi.qld.gov.au/fieldcrops/17654.htmlgt
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Figure 13. Subsurface drip irrigation Lateral
injector (Source Netafim Australia)
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Advantages of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Irrigation There is a high degree of water
  application control with the potential for high
  uniformity of application. 
• Agronomical practices The partial soil wetting
  provided by SDI has several benefits
• - Improved efficiency of nutrient
  uptake at the fringes of the wetted soil volume.

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Advantages of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• - Less water lost from soil surface evaporation
• - Less weed germination and growth
• - Unrestricted travel for field
  operations such as spraying and harvesting
• - Improved access to rainfall
  infiltration in some row crop situations
• - Maintains dry crop foliage
• - Fertigation can be used with SDI.

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Advantages of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

•  
• Salinity problems Saline irrigation water
  applied through SDI will have less effect on
  crops than if applied through surface or
  sprinkler irrigation.
• Water use efficiency Usually SDI water use
  savings range from 0 to 50 when compared with
  traditional irrigation systems.
• Yield improvement Improved yields have been
  obtained with SDI installations.

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Limitations of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Emitter clogging The high distribution
  uniformity inherent in a well-designed SDI system
  can be readily destroyed through emitter clogging
  
• System shutdown Water will flow to the lowest
  point in the field

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Limitations of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Chemical treatments There are no herbicides
  registered in Australia to prevent root
  intrusion.
• Salt accumulation When saline water is used,
  salts accumulate at the wetting front. In SDI,
  this results in an accumulation of salt above and
  mid-way between the laterals. 

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Limitations of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Mechanical damage SDI laterals must be installed
  at the required depth below the ground surface
  along the full length of the field. 
• Mice damage can be significant on cracking soils
  used to grow grain crops
• Insect damage has been a significant problem on
  some SDI sites. There are a number of possible
  insects that chew through SDI tape. 

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Limitations of SDI
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• Crop establishment Soil type and the depth of
  placement of the SDI laterals will determine the
  ability of the system to wet the soil surface to
  aid the crop establishment.
• Soil structural effects In certain soils the use
  of high quality water through SDI has resulted in
  increasing clay content, exchangeable sodium
  percentage and calcium - magnesium ratio away
  from the emitter.

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DRIP IRRIGATION RESEARCH
• Basic aspects for consideration in drip
  irrigation research
• Atmospheric conditions
• Precipitation
• Et (ET)
• Climatic parameters
• Soil
• Classification
• Physical properties
• Chemical properties

90
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• DRIP IRRIGATION RESEARCH
• Basic aspects for consideration in drip
  irrigation research
• Characteristics of Irrigation System
• Physical characteristics of the system
• Quality of the water
• Irrigation programming or scheduling
• Crop Characteristics
• Type of crop (species, variety)
• Factors that affect the growth
• Crop response
• Crop yield

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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
Drip Irrigation System http//www.eng.fsu.edu/abi
chou/projects/FEETC/photo/irrigation20system.jpg
92
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation
Drip irrigation system installed on
risers lthttp//www.cfwc.com/_images/about/drip.jpg
gt
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Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• BIBLIOGRAPHY
• Goldberg, D., Gornat and D. Rimon, 1976. Drip
  Irrigation Principles, Design and Agricultural
  Practices. Drip Irrigation Scientific
  Publications, Kfar Shmaryahu, Israel.
• Goyal, M. R., J. A. Santaella y L.E. Rivera,
  1982. El tensiómetro su uso, instalación y
  mantenimiento. Colegio de Ciencias Agrícolas,
  Servicio de Extensión Agrícola, Recinto
  Universitario de Mayagüez, Río Piedras-E.U.A, A.
• Israelson, D. W. y V. E. Hansen, 1965. Principios
  y Aplicaciones del Riego. Editorial Reverte. S.
  A., Barcelona-España.

94
Chapter VI Principles of Drip/ Micro or Trickle
Irrigation

• BIBLIOGRAPHY
• Jensen, M. E., 1980. Design and Operation of
  Farm Irrigation Systems. ASAE Monograph No. 3,
  American Society of Agricultural Engineers, St.
  Joseph MI, USA.
• Ross, D. S., R. C. Funt, C. W. Reynolds, D. S.
  Coston, H. H. Fries and N. J. Smith, 1978.
  Trickle irrigation and introduction. The
  Northeast Regional Agricultural Engineering
  Service (NRAES), NRAE-4, Cornell University,
  Ithaca, NY-USA.
• Ross, D.S., R.A. Parsons, W.R. De Tar, H. H.
  Fries, D. D. Davis, C. W. Reynolds, H.E.
  Carpenter and E.D. Markwardt, 1980. Trickle
  irrigation in the Eastern United States.
  Cooperative Extension Service NRAES-4 Cornell
  University, Ithaca, NY-USA.

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• There is no greater barrier than the one we
  create ourselves, keep going further.
• Osvaldo Caraballo