Describe the main irrigation systems that are adopted in India.
Different kinds of irrigation systems are adopted to supply water to agricultural lands depending on the kinds of water resources available.
These include wells, canals, rivers and tanks.
Wells: They are of two types dug wells and tube wells. In dug wells, water is collected from water bearing strata while in tube wells water is tapped from the deeper strata. From these wells, water is lifted by pumps for irrigation.
Canals: Canal system is usually an elaborate and extensive irrigation system. Canals receive water from one or more reservoirs or from rivers. The main canal is divided into branch canals having further distributaries to irrigate fields.
River lift systems: In this system, water is directly drawn from the rivers for supplementing irrigation in areas lying close to rivers. This system is used in areas where canal flow is insufficient or irregular due to inadequate reservoir release.
Tanks: Tanks are small storage reservoirs, which intercept and store the run-off of smaller catchment areas.
Apart from the above systems, some new initiatives have been undertaken for increasing the water available for agriculture. These include rainwater harvesting system and watershed management system. This involves building small check-dams which lead to an increase in groundwater levels. These check-dams stop the rainwater from flowing away and also reduce soil erosion.