What is Irrigation?
[[File:Trebinje P1015109mod.jpg|thumb|Trebišnjica River Wheels, Bosnia.]] '''Irrigation''' is when people add [[water]] to [[plant]]s, to help them grow when there is [[water scarcity|not enough rain]]. Irrigation water can be pumped from [[river]]s, natural [[lake]]s or lakes created by [[dam]]s, from [[well]]s or allowed to flow to the fields by or open [[canal]]s. == Types of Irrigation == There are many different types of irrigation methods. The most common ones are: # Sprinkler Irrigation # Drip irrigation # Surface irrigation # Sub surface irrigation # Manual irrigation Sprinkler irrigation mimics natural rainfall where water falls on the plants. In sprinkler irrigation, water is moved through pipes to sprinklers scattered around and within the field. The [[Sprinkler]]s shoot water from pressurized outlets or guns from pipes into the air which then fall on the plants. Center pivot irrigation is a type of sprinkler irrigation. It's basically, sprinklers on wheels. In drip irrigation, water drips directly to the roots of plants from pipes which have small holes or special emitters spaced along the pipe. Drip irrigation is more efficient than other irrigation methods because water is applied directly or close to plants' roots i.e. where it is needed. Thus, it uses less water, reduces leeching of soil nutrients and [[erosion]] of top soil. In Surface irrigation, water from a source such as rivers, pipes, dams, canals e.t.c. floods the soil surface. Surface irrigation uses a lot of water compared to other irrigation methods. It could also drain nutrients beyond the reach of the plant roots. If the water is excessive, it could cause damage to the plant. However, surface irrigation is used extensively in rice farming. This is because the permanent flooding acts as a natural pest control method<ref>{{Cite journal|last1=Tindall|first1=Kelly V.|last2=Bernhardt|first2=John L.|last3=Stout|first3=Michael J.|last4=Beighley|first4=Donn H.|date=2013|title=Effect of depth of flooding on the rice water weevil, Lissorhoptr