Understanding
Drip irrigation
www.karmayog.org (10.10.2013 http://en.wikipedia.org/wiki/Drip_irrigation
http://www.fao.org/docrep/s8684e/s8684e07.htm#6.2
drip system layout http://www.dripirrigation.org/
http://www.jaindrip.com/
Drip
irrigation, also known as trickle irrigation or micro
irrigation or localized irrigation, is an irrigation method that saves water and
fertilizer by allowing water to drip slowly to the roots of plant either onto
soil surface or into root zone. This is done through a network of valves,
pipes, tubes and emitters. The diagram below taken
explains the system of drip irrigation.
Basically micro irrigation
takes water from a source (well in diagram) and distributes it through the farm
by means of systems of pipes. There are valves to both control the flow of
water ahead and also to prevent backward flow of water (through NRV). From the
water source, a pump pressurizes water out; this is followed by water filtration
system; this is followed by a fertigation system for administering fertilizers
or a chemigation system to apply pesticides; a backwash controller ahead
prevents back flow of fluid; pressure control valve regulates pressure; a main
line takes the water ahead; this is followed by hand operated valves; a small
diameter polytube takes water ahead and there are poly fitting to make emittino
emitting devices which drip water. (See diagram below)
Drip Irrigation system offers
several advantages such as :
1. Greater
Yields
2. Water
efficiency
3. Minimal
fertilizer wastage
4. Minimisation
of soil erosion
5. Reduced
Labour Cost
6. Reduced
Energy Cost
7. Reduced
Pesticide cost.
8. Uniform
Water Distribution
9. Reduction
in Weed Growth
10. Foliage
is dry reducing risk of disease
A typical drip irrigation system as shown above consists of the
following components pump unit, control head, main and submain lines,
laterals, emitters or drippers. The pump
unit takes water from the
source and provides the right pressure for delivery into the pipe system. The control head consists of valves to control the
discharge and pressure In the entire system. It may also have filters to clear
the water. Some control head units contain a fertilizer or nutrient tank. These
slowly add a measured dose of fertilizer into the water during irrigation. Mainlines,
submains and laterals supply
water from the control head into the fields. Emitters or drippers are devices used to
control the discharge of water from the lateral to the plants.