Geography
Canals are a channel for supply of water from rivers to the farm fields. The perennial canals are not only an advantage but can be disadvantageous too. The perennial canals are functional in the state of Punjab due to the favourable situations available there.
(i) What conditions favour the development of canal irrigation in the mentioned area?
(ii) State two disadvantages of it.
Answer
(i) The following conditions favour the development of canal irrigation in Punjab:
- Presence of rivers (like Sutlej, Beas, and Ravi)
- Gentle slope of land
- Extensive farmlands
- Low rainfall
- Alluvial soil
(ii) Two disadvantages of Canal irrigation (perennial) are as follows:
- In areas where perennial unlined canals flow at ground level and between raised high banks, the water table may rise excessively, leading to waterlogging and swamp formation, rendering the soil uncultivable.
- Waterlogging reduces the soil's ability to absorb water, so even slight excess rainfall can flood the land, damaging crops, homes, and stored goods due to poor drainage.
Related Questions
How are the fields irrigated using the Persian wheel method?
Give a geographical reason for each of the following:
(i) Canals make the soil infertile.
(ii) Tubewell irrigation is quite expensive.
(iii) Excessive accumulation of salts make the soils unsuitable for cultivation.
Briefly explain why groundwater levels are dropping rapidly in India.
How can groundwater be recharged? Name a method to recharge groundwater.