Micro irrigation systems have many potential advantages when compared to
other irrigation methods.
Water savings: irrigation water
requirements can be smaller when compared to other irrigation methods.
This is due to irrigation of a smaller portion of the soil volume,
decreased evaporation from the soil surface and the reduction or
elimination of the runoff. Since the micro irrigation system allows for a
high level of water control application, water can be applied only when
needed and deep percolation can be minimised or avoided.
Water efficiency: can reduce water
usage by 25-40% compared to overhead systems, and 45-60% compared to
surface irrigation, because do not wet the entire field, less
-evaporation, deep percolation and the runoff minimised, too.
Low application rates: micro
irrigation systems are design to supply an individual plant's water
requirement by a daily application. A low application rate means a less
expensive irrigation system and more efficient utilisation of pumps,
filters and pipelines because these system components may be sized for
lower flow rates and used for longer periods of time.
Uniformity of water application: micro
irrigation systems have an excellent uniformity of water application,
therefore all plants receive the same amount of
water. Good uniformity results in more efficient irrigation, which leads
to savings of water, power and fertiliser. An even, consistent application
of water also results in better, more uniform yields, because each plant
is given exactly as much water and nutrients as it needs for optimum
Energy saving: a
smaller power unit is required compared to other irrigation systems.
Usually, the delivery pipe systems operate under low pressure (2 - 4 bar)
and requires less energy for pumping.
Improved chemical application: micro irrigation systems allow for a
high level of control of chemical applications. The plants can be supplied
with the exact amount of fertiliser required at a given time. Since they
are applied directly to the root zone, a reduction in the total amount of
fertiliser used is possible (average 25-50% cost savings in chemicals and
fertilisers). This application method is more economical, provides better
distribution of nutrients throughout the season and decreases ground water
pollution due to the high concentration of chemicals that could ordinarily
move with deep percolated water. Other chemicals such as herbicides,
insecticides, fungicides, growth regulators and carbon dioxide can be
efficiently applied through micro irrigation systems to improve crop
Weed and disease reduction: because of limited wetted area, weed
growth is inhibited and disease occurrences reduced.
Field operations are more flexible: can be applied on windy days and
during operations, can function without interruption when harvesting.
Improved tolerance to salinity: micro irrigation reduces the
sensitivity of most crops to saline water, soil-water conditions due to the
maintenance of high moisture levels in the root zone. The frequent
application of water continually replaces moisture removed by the plant
and moves salts away from the plant out to the edges of the root zone.
These salts precipitate out of the water at the edge of the wetted
parameter. This process prevents the harmful combination of high soil
salinity and low moisture from occurring. Therefore, crops under micro
irrigation systems are more tolerant of saline water and soil conditions.
Improved quality and yield: crop
quality and yield under micro irrigation is improved because of the slow,
regular, uniform application of water and nutrients. In addition damage
and losses due to water contact with fruit or foliage are eliminated.
Adoption to any topography and soils:
micro irrigation systems can operate efficiently on any topography if
appropriately designed and managed. The low application rate that micro
irrigation systems provide is ideal for heavy clay soils with low
infiltration rates as the water can be applied slowly enough for the soil
to absorb it without surface runoff occurring. On the other hand, very
sandy soils frequently cannot store large amounts of water. Micro
irrigation is ideal for these soils too, because of its ability to frequently
provide small amounts of water to the crop.
Automation: a micro irrigation
system can be easily automated using electrical solenoid valves and a
controller. This allows the system to be operated any time of the day or
night and for any desired length of time enabling irrigation managers to
take advantage of available crop water use information in determining
optimum irrigation time. Soil moisture sensors can be used to further
automate the system.
Reduced labour cost: one of the major
advantages of the micro irrigation system is labour savings. Labour
requirements are low because of the low application rates allow larger
areas to be irrigated at one time and because the systems can be fully
automated. In addition to the direct savings in labour, there are often
indirect labour savings due to the reduced number of cultivations, the
elimination of fertiliser application as a separate operation.
Most of the sprinklers, sprayers and jets are
insect protected - nozzles are closed after operation to avoid any
clogging caused by insects or other debris.
If these benefits are not achieved, the
investment in a micro irrigation system is not worth it. Product
life with good quality equipment, good operation and management can last
up to 15-20 years.