Water-saving rice trick backfires in saltier coastal soils
Climate Adaptation
If you garden or farm near a coastline, this shows that a popular water-saving technique can quietly concentrate salt in soil to the point where it hurts your harvest, so the right irrigation choice depends on how salty your ground already is.
Farmers have been drying out and reflooding rice fields on a cycle instead of keeping them constantly flooded, because it uses less water. Researchers tested this in two coastal areas of Bangladesh with different salt levels in the soil and found that in the less-salty area, it saved water and yields stayed the same. But in the saltier area, the same technique let salt build up in the soil as the season went on, and farmers ended up with about 14% less rice even though they still used water more efficiently.
Key Findings
In low-salinity Barishal, alternate wetting and drying (AWD) raised irrigation water productivity by 21-30% over continuous flooding without reducing rice yield.
In medium-salinity Khulna, AWD increased soil salinity (EC 1:5) progressively through the season and led to roughly 14% lower grain yield compared to continuous flooding.
Despite the yield loss in Khulna, AWD still boosted water productivity there by 21-29% over continuous flooding, highlighting a trade-off between water efficiency and yield in saltier soils.
chevron_right Technical Summary
A water-saving irrigation method for rice, called alternate wetting and drying, cuts water use and boosts water efficiency without hurting yields in low-salinity coastal soil, but in moderately salty soil it raises soil salt levels and cuts grain yield by about 14%.
Abstract Preview
Original paper
Assessing the impact of alternate wetting and drying irrigation on soil salinity, water productivity, and Boro rice yield in coastal saline regions of Bangladesh
Alternate Wetting and Drying (AWD) irrigation is widely promoted for rice cultivation to reduce water use and enhance water productivity. However, its performance under saline conditions remains in...
open_in_new Read full abstractAbstract copyright held by the original publisher.
Species Mentioned
Was this useful?
Want to tell us more? (optional)
Thanks for the note!
Something went wrong — please try again.
Too many submissions. Try again in an hour.
Targeted knockout of a host peroxisomal peptidase confers field resistance to...
The corn in your grocery store and the staple food keeping millions of East African families fed is under serious threat from a viral disease that can wipe o...
Rice is a cereal grain and in its domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species Oryza sativa —or, much less commonly, Oryza glaberrima. Asian rice was domesticated in China some 13,500 to 8,200 y...