Alternate wetting and drying combined farmyard manure for reducing greenhouse gas while improving rice yield

Abstract

Water and organic amendments are the most important factors controlling methane (CH ) emissions from paddy fields. Alternate wetting and drying (AWD) in rice cultivation improve water productivity (WP), minimize methane emission, but might increase nitrous oxide emissions (N O). The effects of combined water management and organic manure application on methane and nitrous oxide emission, rice yield are not well documented. The objective of this experiment was to determine rice cultivation technology that can improve productivity and reduce GHG emissions on rice field. The Inpari 32 rice cultivar was used in this study. Closed chamber methods were used for measuring emissions of greenhouse gases. Our results showed that, in comparison with continuous flooding, the AWD significantly reduced total global warming potential (GWP) by 13–17%. The AWD technique increased grain yields by 6-7% compared with those of CF. The AWD technique reduced CH (14–18%) and increased water productivity by 7–12% compared to CF system, along an 18–23% reduction in GHG intensity (GHGI). In conclusion, AWD technique and soil amendment with farmyard manure could be effectively used in greenhouse gas mitigation strategies for reducing GHG emission, GWP, and GHGI without sacrificing rice yield.