CBSE Class 9 Answered

Traditional methods of irrigation

Canal irrigation

• In India, irrigation of extensive areas is carried out by canals.
• The main canal receives water from different sources such as reservoirs or rivers and branches further for irrigation.

Moat/Pulley system

• The pulley system along with a rope and bucket is known as a moat.
• Water is lifted out from the well by using a bucket attached to a rope which passes over the pulley. The rope is either pulled by man or by animals.
• Water is directly taken out from wells and used to irrigate fields.

Persian wheel (Rahat system)

• A Persian wheel is a simple water-lifting device.
• It consists of a large wooden wheel with several buckets arranged on its outer rim. The whole arrangement is submerged in an open well.
• The wheel is yoked to a pair of animals like bullocks. They move around in circles thus rotating the wheel and, in turn, the buckets.
• The buckets dip in the well, collect water and empty it into an intricate network of channels which distribute water in the cropped area.

Swing basket method

• The swing basket is an ancient water-lifting device.
• It consists of a bamboo basket to which four ropes are attached.
• Two people stand facing each other and swing the basket to fill in water.
• The basket is raised and water is discharged in the crop field.

Dhekli

• Dhekli is generally used to lift water from an unlined well, stream or pond.
• It consists of a lever rod supported on a vertical post about which it can swing in a vertical direction. 

Chain pump

• The chain pump is used to lift water from a shallow well. 
• It is useful to lift water from a depth of about 6 metres.  

Modern methods of irrigation

Basin irrigation

• It is a kind of surface irrigation.
• The land is surrounded with embankments in the form of a basin.
• Basins are flooded with water.
• It is used for crops which require a large amount of water to grow.

Furrow irrigation

• It is a kind of surface irrigation.
• Small channels or furrows are created along the field length between crop rows.
• It is used for crops which do not require much water.

Drip irrigation

• Water is supplied through perforated pipes.
• Pipes are placed in rows between the plants close to the roots.
• It is the best method for water scarce regions because a lot of water is saved.
• It is used for fruit orchards, gardens and trees.

Sprinkle irrigation

• Sprinklers or spray guns are attached to a large hosepipe at regular intervals to spray water.
• It is suitable for all types of crops.