| Summary: | Improved irrigation management is identified as a potential mitigation option for methane (CH<sub>4</sub>) emissions from rice (<i>Oryza sativa</i>). Furrow-irrigated rice (FR), an alternative method to grow rice, is increasingly adopted in the Mid-South U.S. However, FR may provide a potential risk to yield performance and higher emissions of nitrous oxide (N<sub>2</sub>O). This study quantified the grain yields, CH<sub>4</sub> and N<sub>2</sub>O emissions from three different water management practices in rice: multiple-inlet rice irrigation (MIRI), FR, and FR with cereal rye (<i>Secale cereale</i>) and barley (<i>Hordeum vulgare</i>) as preceding winter cover crops (FRCC). CH<sub>4</sub> and N<sub>2</sub>O fluxes were measured from May to September 2019 using a static chamber technique. Grain yield from FR (11.8 Mg ha<sup>−1</sup>) and MIRI (12.0 Mg ha<sup>−1</sup>) was similar, and significantly higher than FRCC (8.5 Mg ha<sup>−1</sup>). FR and FRCC drastically reduced CH<sub>4</sub> emissions compared to MIRI. Total seasonal CH<sub>4</sub> emissions decreased in the order of 44 > 11 > 3 kg CH<sub>4</sub>-C ha<sup>−1</sup> from MIRI, FR, and FRCC, respectively. Cumulative seasonal N<sub>2</sub>O emissions were low from MIRI (0.1 kg N<sub>2</sub>O-N ha<sup>−1</sup>) but significantly higher from FR (4.4 kg N<sub>2</sub>O-N ha<sup>−1</sup>) and FRCC (3.0 kg N<sub>2</sub>O-N ha<sup>−1</sup>). However, there was no net difference in global warming potential among FR, FRCC and MIRI. These results suggest that the increased N<sub>2</sub>O flux from furrow-irrigated rice may not greatly detract from the potential benefits that furrow-irrigation offers rice producers.
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