The supply of water to crops at regular intervals is called irrigation. Methods of irrigation which conserve water are as follows :-
a) Drip Irrigation: The irrigation in which the water goes drop by drop directly into the roots. This is a type of micro-irrigation system in which water is allowed to drip slowly to the roots of plants either from above the soil surface or to the roots that is buried below the surface. Thus this process of watering plants minimizes evaporation of water. Hence this method is very useful as it conserves the water and also prevents us from irrigating the weeds.
b) Sprinkler Irrigation: This method is used mainly in uneven land where sufficient water is not available. 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. An irrigation sprinkler is used as a device for this type of irrigation. It is also used for cooling and for the control of airborne dust. Thus water from a sprinkler gets sprinkled on the crop as if it is raining.