From over to optimal irrigation in paddy production: what determines over-irrigation in Bangladesh?
Category:- Journal; Year:- 2021
Discipline:- Economics Discipline
School:- Social Science School
Abstract
This paper examines the level of optimal irrigation and the
determinants of over-irrigation in paddy production since about three-fourth of
freshwater withdrawal is used to irrigate paddy plants in Bangladesh.
Cobb-Douglas production function reveals that optimal irrigation is 75 × 10 2 m
3 per acre per season. Results show nearly, 39% of water is over-irrigated. It
escalates farmer's irrigation cost by USD 56 per acre and induces additional
depletion 60 × 10 2 million m 3 freshwater with substantial welfare loss USD
70-73 million in southwestern Bangladesh. Further analyses reveal that farm
characteristics, salinity, and irrigational modes determine over-irrigation in
the study area. This study suggests that the alternate wetting and drying (AWD)
technique helps farmers to reduce irrigation substantially and to reach the
optimal level. Welfare effects of the AWD technique are 89-93% reduction in
over-irrigation 68-71% reduction in ancillary cost.