In recent years, global warming has been progressing due to increases in greenhouse gas concentrations in the atmosphere. Greenhouse gas emissions from agro-ecosystems impact global warming. In particular, CH4 and N2O are mainly emitted by agricultural activities. Rice cultivation is a primary source of CH4. Reducing CH4 and N2O emissions in paddy fields is essential for mitigating global warming. Water management impacts the production of greenhouse gases in paddy fields. To understand the dynamics of soil-produced greenhouse gases, determining soil gas concentrations is necessary. In this study, Rice (Oryza sativa L., cultivar Kinuhikari) was grown under different water management practices, and rice yield and greenhouse gas (CH4, CO2, N2O) production in soil were measured to investigate the effects of water management. Soil gas concentrations of CH4 were high when the soil was flooded and low when the soil was drained. On the other hand, N2O concentration was low when the soil was flooded and high when the soil was drained. This may be because NO3- was produced in soil by nitrification. Therefore, soil water management may play a key role in mitigating greenhouse gases in paddy fields.
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