Home General Knowledge GK SPECIAL TOPIC : DRIP IRRIGATION
GK SPECIAL TOPIC : DRIP IRRIGATION
Tuesday, 22 April 2014 07:53

 

GK SPECIAL TOPIC

 

DRIP IRRIGATION

Drip irrigation—also known as low-flow, micro, and trickle irrigation—is the slow, measured application of water through devices called emitters. Under this system, water is carried to the plant under low pressure, through small diameter plastic pipes and delivered at the root zone, drop by drop through drippers.

Drip irrigation was invented in the early 1960’s as an efficient way to water agricultural crops. Now, a wide variety of quality products has been developed to make drip irrigation reliable and easy to use for almost any landscape situation. Drip irrigation is widely practised and established method of irrigation in developed countries and is slowly gaining popularity in India. It is most suited for horticulture crops, vegetables etc. and finds applicability in hard rock areas where groundwater is scarce and helps in optimisation of the limited water resources.

As a policy to encourage use of such systems, the Govt. of India has announced the Centrally Sponsored Micro Irrigation Scheme during 2005-06. The total cost of the scheme is being shared between Central Government, the State Government and the beneficiary either through his/her own resources or soft loan from financial institutions in the ratio of 40%, 10% and 50% respectively. Bankable schemes have to be formulated for availing bank loans.

Basic Parts of a Drip System:

a) CONTROLLER/ TIMER:

Controls the watering cycle by automatically activating the control valves on the preselected days and times, thereby directing when, how long and how often the system operates.

b) BACKFLOW PREVENTOR:

This device prevents the irrigation system water from being siphoned back into drinking water. Your water provider may regulate the installation of backflow preventers.

c) VALVES:

Manually or automatically operated control valves are used to turn the water on and off. Automatic control valves are wired to a controller.

d) FILTER:

All drip systems need some type of filter to keep dirt and debris from clogging the emitters.

e) PRESSURE REGULATOR:

Most drip systems operate at low pressure, usually less than 20 PSI. Pressure regulators reduce incoming water pressure to the ideal pressure for the drip system.

f) PIPE:

Polyethylene tubing and rigid PVC are the two most commonly used types of pipe.

g) MICRO-TUBING:

Also known as “1/4 inch” or “spaghetti” tubing delivers water from the emitters to the plants, or from the poly tubing to the emitter.

h) EMITTERS:

These connect to the tubing or can be inside the tubing and deliver water at a slow, consistent rate, usually, 0.5, 1, 2 or 4 gallons per hour.

i) FLUSH VALVE/ END CAP:

A flush cap is attached to the end of each irrigation line so that dirt and debris can be flushed out of the irrigation system.

Advantages of Drip Irrigation:

a) Water savings, since only those areas directly around the plants root zone are irrigated.

b) Plants undergo less stress from variations in soil moisture, therefore plant appearance is enhanced.

c) Constant moisture improves plant growth.

d) Slow application rate prevents excess surface water build-up and reduces evaporation.

e) The low application rate and the use of automatic timers’ results in precise water control.

f) Weed growth is reduced because areas between plants are not irrigated.

g) System can be designed for use in all types of terrain and soil conditions.

h) System’s low flow rate allows irrigation of larger areas and more plants can be watered at once.

i) Drip irrigation systems are usually installed at costs considerably less than those of an underground sprinkler, bubbler, or shrub spray system.

j) Through the use of fertilizer dispensers, chemicals and nutrients can be fed directly to the plant in controlled quantities.

k) The water application rate can be tailored to fit each individual plant. This is accomplished by the use of different quantities of emitters and emitters with different discharge rates.

l) Conversion to drip irrigation is easily accomplished since the hydraulic design of a sprinkler system is more than adequate.

m) The drip system is economical to use with native landscapes in dry weather conditions.

 


Last Updated on Wednesday, 23 April 2014 07:16