Question

why are flood plain densely populated

Answer 1

Because as it is flood plain area the fertile alluvial soi gets deposited on that area & hence makes that area fertile & fit for agricultural & hence it is densely populated

Answer 2

fertile soil-flood plain area has fertile soil which help in growing any type of crop agriculture can be easily done here that is why mostly population like to live there

Industrial Area-Mostly Industries set up plane area due to easily transportation,Availability of Market,banking facility

Availability of water-Water is easily available from plain area this is also a reason that mostly population live there

Suitable Climate-The climate of plain area suit the popultion due to availability of moderate climate