CH4 transport mechanisms via rice plants: a new approach using isotopic fractionation of 13C-CH4

• Project/Area Number: 25660200
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Agricultural environmental engineering/Agricultural information engineering
• Research Institution: National Institute for Agro-Environmental Sciences
• Principal Investigator: TOKIDA Takeshi 独立行政法人農業環境技術研究所, その他部局等, 研究員 (20585856)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2013: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: メタン / 水田 / イネ / 炭素安定同位体比 / ガス輸送 / 移流 / 拡散

Outline of Final Research Achievements

Rice paddies represent one of the largest anthropogenic sources of atmospheric CH4. Methane is produced by methanogens in anoxic soil and released into the atmosphere mainly via aerenchyma tissue of rice plants; however physical mechanisms of the emissions remain unclear. In this study CH4 emission was measured at a farmer's rice paddy, showing a large (>2-3 folds) diurnal variation in CH4 emissions after the middle of the growth season. The larger emissions during the daylight hours accompanied relatively heavier CH4 (enriched in 13C) while smaller emissions during the nighttime were characterized with lighter (less 13C) CH4. These results suggest occurrence of and shift in different transport mechanisms of CH4 through rice plants.

Research Products

• [Journal Article] Fully automated, high‐throughput instrumentation for measuring the δ13C value of methane and application of the instrumentation to rice paddy samples (2014)
  • Author(s): Takeshi Tokida, Yasuhiro Nakajima, Kentaro Hayashi, Yasuhiro Usui, Nobuko Katayanagi, Masako Kajiura, Hirofumi Nakamura, Toshihiro Hasegawa
  • Journal Title: Rapid Communications in Mass Spectrometry Volume: 28 Issue: 21 Pages: 2315-2324
  • DOI: 10.1002/rcm.7016
  • Peer Reviewed / Acknowledgement Compliant