Why is water needed by plants?
All living organisms require water including plants
Water helps plants roots in absorbing nutrients from manures and fertilizers
Seeds do not grow without supply of water
Water also helps in protecting crop from hot and cold air
What is irrigation
It is the process of supplying water to plants at regular intervals
Supply of Water
to plants
at regular intervals
is called irrigation
Why is irrigation done/What are benefits of irrigation?
- Seeds cannot grow in dry soil Water is required by plants for germination
- Water dissolve nutrients in soil so that plant can absorb it
- Water is required to be added for loosening soil before ploughing
When is irrigation more required
Irrigation of crops is higher in summer due to the increase in the rate of evaporation of water from the soil and the leaves.
Source of irrigation
Water is provided from wells, tube wells, ponds, rivers, dams, canals
Different Irrigation Methods
Traditional Methods
They use manual labour or cattle to draw water from wells
Example
- Moat(Pulley System)
- Chain Pump
- Dhekli
- Rahat
Moat(Pulley System)
Water is drawn from well with the help of animal like bullock
Animal pulls rope from one end,bucket of water comes out of well from other end
Chain Pump
It has 2 wheels connected to chain,
One wheel is on ground,other is in pond or lake
Bucket is attached to chain
When handle of upper wheel is rotated,lower wheel also turns and water is filled in bucket
This filled bucket water moves up which is used for irrigation
Dhekli
A wooden beam is put over a forked support
Long arm of wooden beam is towards well,short arm is away from it
Weight is tied to shorter arm
Bucket is attached to longer arm and it is pulled down in well
When it is filled with water,rope is released
Weight of stone pushes bucket up
Rahat
It contains a large wheel.On Well there is a long belt which contains many metal pots
Wheel is rotated with the help of lever which is pulled by bullock cart
When wheel rotates, Lower end of belt dips in water of well metal pots get filled in water
They are drawn up ,water is emptied and the process is repeated
Use of Pumps for Irrigation
In traditional method,human labour or animals were used for lifting water for irrigation.
So,the traditional method was cheaper but less efficient.
These days pumps are used for lifting water(from wells,stream,lake,ponds and rivers).
These pumps run by electricity,solar energy,diesel and biogas.
Nowadays,tube wells are used for irrigation in agriculture.
Modern Methods
Innovative Methods are used like
Sprinkler System
It has a pump,different perpendicular pipes and nozzle
When pump is opened,water sprinkles out from different nozzles
It is used for
- Lawns
- Coffee Plantation
It is mainly used in case of sandy soil or uneven land
Drip System
Water drips drop by drop to root of plant directly
There is no wastage of water in this case.
It is useful in those regions where availability of water is poor
It is used in case of watering of
- fruits
- trees
- Gardens
How does Irrigation depends on Nature of Soil and Nature of Crops
Nature of Soil
Nature of Crop
Every crop requires specific amount of water during various stages for its growth and ripening
Example-
Paddy crops are transplanted in standing water and require continuous irrigation.
While some crops do not require much water
Example-Gram and Cotton
Wheat crop requires water only at 3 stages
- Before ploughing the field
- At the time of flowering
- At the time of development of grains
Questions
NCERT Question 6 - What is irrigation? Describe two methods of irrigation which conserve water
NCERT Question 11 (1) - Complete the following word puzzle with the help of clues given below
Providing water to the crops
