What is irrigation? Describe two methods of irrigation which conserve water.

The supply of water to crops at different intervals is called irrigation. The two methods of irrigation which conserve water are as follows:
(i) Sprinkler System:
Under this method, the perpendicular pipes, having rotating nozzles on top, are joined to the main pipeline at regular intervals. When water is allowed to flow through the main pipe under pressure with the help of a pump, it escapes from the rotating nozzles. It gets sprinkled on the crop as if it is raining.
(ii) Drip system:
In this system, the water falls drop by drop just at the position of the roots. It is the best technique for watering fruit plants, gardens and trees. Water is not wasted at all. It is a boon in regions where availability of water is poor.

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