People in the flood plains of Bengal created inundation channels to irrigate their fields.
Agricultural fields in arid and semi-arid regions were converted into rain-fed storage structures that allowed water to stand and moisten the soil, such as the ‘khadins’ in Jaisalmer and ‘Johads’ in other parts of Rajasthan.
Floodwater entered the fields via inundation canals, bringing not only rich silt but also fish, which swam through these canals into lakes and tanks to feed on mosquito larvae.
This aided in the control of malaria in this region.
In Bengal, people use this method to irrigate fields and flood water, as well as to attract fisher to the fields.
More than 300 students in West Bengal are distributing Gambusia fish, which feed on mosquito larvae.
Final Answer:
The purpose of inundation channels is to carry overflow water from rivers from rain (floods) to fields for irrigation. Inundation channels are channels that perform this function. Bengal has an incredible system of inundation canals.