Alternate wetting and drying

Alternate wetting and drying (AWD) is a simple and inexpensive way of reducing water consumption in rice production by 30%, thus, enabling farmers to cut down on production cost without yield penalty. AWD entails periodic draining of the field to a certain threshold, usually 15 cm below the soil surface, and re-flooding. A perforated tube placed in the soil enables the farmer to monitor the water level below the soil surface to determine when to irrigate.

The AWD technology has also been proven to effectively mitigate greenhouse gas (GHG) emission, specifically methane (CH4), from rice production by 30-70%, without causing a yield reduction. During the dry phases, the methane-producing bacteria are inhibited, thus, setting a condition to reduce GHG emission. 

Further reading

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