Clarification of winter dynamics of soil CO2 fluxes in the Arctic tundra ecosystem and their estimation throughout the year.

• Project/Area Number: 16H05622
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Environmental dynamic analysis
• Research Institution: National Institute of Polar Research
• Principal Investigator: Masaki Uchida 国立極地研究所, 国際北極環境研究センター, 准教授 (70370096)
• Co-Investigator(Kenkyū-buntansha): 米村 正一郎 県立広島大学, 生物資源科学部, 教授 (20354128)
• Project Period (FY): 2016-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥17,420,000 (Direct Cost: ¥13,400,000、Indirect Cost: ¥4,020,000); Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2019: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2018: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2017: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2016: ¥6,370,000 (Direct Cost: ¥4,900,000、Indirect Cost: ¥1,470,000)
• Keywords: 極地 / 土壌呼吸 / 二酸化炭素 / ツンドラ / 炭素循環 / ツンドラ生態系 / 冬期 / 連続測定 / 土壌CO2フラックス

Outline of Final Research Achievements

We conducted year-round observations of carbon dioxide (CO2) concentrations in the soil in a high Arctic tundra ecosystem and found that CO2 concentrations changed dynamically during the winter, even though the soil was freezing. The involvement of Rain-on-Snow (ROS) events on soil CO2 concentration was revealed for the first time in this study. The impact of rain-on-snow on CO2 flux from the soil was estimated to be increased CO2 emissions by 10% in the case of the winter season from 2016 to 2017. A new model was constructed by this study for an estimation of annual soil CO2 flux. It became clear that new mechanisms of CO2 dynamics need to be incorporated into the model to improve soil CO2 flux estimation.

Academic Significance and Societal Importance of the Research Achievements

本研究では、土壌中の二酸化炭素濃度は、土壌が凍結している冬期において、大きく変動していることを初めてあきらかにした。その変動の要因として、マイナスの温度域からプラスの温度域にまで上昇する急激な温度変化が考えられた。この温度変化の際には降雨が見られるため、北極域ではRain-on-Snow(ROS)イベントとして知られている。このROSイベントにより、地表面に氷の層が形成され、トナカイがエサを食べられなくなることが問題となっている。本研究において、ROSが土壌からのCO2放出量を増加させることが示唆されたことから、炭素循環の視点からも重要なイベントであることを本研究で初めて示すことができた。

Research Products

• [Int'l Joint Research] The Alfred Wegener Institute(ドイツ)
• [Int'l Joint Research] Alfred Wegener Institute(ドイツ)
• [Int'l Joint Research] Alfred Wegener Institute(ドイツ)
• [Int'l Joint Research] Alfred Wegener Institute(ドイツ)
• [Int'l Joint Research] Alfred Wegener Institute(ドイツ)
• [Journal Article] Five decades of terrestrial and freshwater research at Ny-Alesund, Svalbard. (2022)
  • Author(s): Pedersen, A.O., Convey, P., Newsham, K.K.ら47人中19番目(Uchida, M.)
  • Journal Title: Polar Research Volume: -
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Identification and Isolation Pattern of Globisporangium spp. from a Sanionia Moss Colony in Ny-Alesund, Spitsbergen Is., Norway from 2006 to 2018 (2021)
  • Author(s): Tojo Motoaki、Fujii Natsumi、Yagi Hironori、Yamashita Yuki、Tokura Katsuyuki、Kida Kenichi、Hakoda Akiho、Herrero Maria-Luz、Hoshino Tamotsu、Uchida Masaki
  • Journal Title: Microorganisms Volume: 9 Issue: 9 Pages: 1912-1912
  • DOI: 10.3390/microorganisms9091912
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Factors affecting water availability for high Arctic lichens. (2017)
  • Author(s): Inoue T., Kudoh S., Uchida M., Tanabe Y., Inoue M., Kanda H.
  • Journal Title: Polar Biology Volume: 40 Issue: 4 Pages: 853-862
  • DOI: 10.1007/s00300-016-2010-2
  • Peer Reviewed
• [Journal Article] Sensitivity analysis of ecosystem CO2 exchange to climate change in High Arctic tundra using an ecological process-based model (2016)
  • Author(s): Uchida M., Muraoka H., Nakatsubo T.
  • Journal Title: Polar Biology Volume: 39 Issue: 2 Pages: 251-265
  • DOI: 10.1007/s00300-015-1777-x
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] CO2 emission resulting from rain-on-snow events amounts to 10% of yearly soil CO2 emission in Ny-Alesund. (2021)
  • Author(s): Yonemura, S., Uchida, M., Kishimoto-Mo, A., Oura, N.
  • Organizer: The 12th Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] 高緯度北極スバールバルの氷河後退域における土壌硝化能の遷移 (2019)
  • Author(s): 林健太郎・田邊優貴子・小野圭介・浅野眞希・服部祥平・内田雅己・早津雅仁
  • Organizer: 日本地球惑星科学連合2019年大会
• [Presentation] Soil respiration rates of seasonally frozen soils in Ny-Alesund. (2019)
  • Author(s): Yonemura S., Kishimoto-Mo, A.W., Oura N., Uchida M.
  • Organizer: The 10th Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Seasonal change of CO2 concentration in soil layers throughout the year on Svalbard, high-Arctic Norway; model construction and first evaluation (2018)
  • Author(s): Uchida, M., Yonemura, S., Sakurai, G., Kishimoto-Mo, A.W., Boike J.
  • Organizer: The 9th Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Simulation of ecosystem carbon cycle in Ny-Alesund, Norwegian High Arctic under environmental change. (2018)
  • Author(s): Uchida, M.
  • Organizer: ArcticNet Arctic Scientific Meeting 2018
  • Int'l Joint Research
• [Presentation] Introduction of Japanese activities in Ny-Alesund. (2018)
  • Author(s): Uchida, M.
  • Organizer: Ny-Alesund Terrestrial Flagship Program workshop
  • Int'l Joint Research
• [Presentation] Ecosystem carbon cycle in Brogger Peninsula, Ny-Alesund, Svalbard. (2017)
  • Author(s): Nakatsubo T., Uchida M.
  • Organizer: Svalbard Science Conference 2017
  • Int'l Joint Research
• [Presentation] The Bayleva high Arctic permafrost long-term observation site: an opportunity for join international research on permafrost, atmosphere, ecology and snow. (2017)
  • Author(s): Boike J., Chadburn S., Cannone N., Schulz A., Biskaborn B., Maturilli M., Uchida M., Westermann S.
  • Organizer: Svalbard Science Conference 2017
  • Int'l Joint Research / Invited
• [Presentation] Preliminary report for measurements of soil CO2 concentrations throughout the year at Ny-Alesund. (2017)
  • Author(s): Uchida M., Yonemura S., Kishimoto M.W.A., Sakurai G., Boike J.
  • Organizer: Svalbard Science Conference 2017
  • Int'l Joint Research
• [Presentation] Preliminary report for measurements of CO2 concentration in soil layers throughout the year on Svalbard, high-Arctic Norway. (2017)
  • Author(s): Uchida M., Yonemura S., Kishimoto-Mo A. W., Sakurai G., Boike J.
  • Organizer: The 8th Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Estimation of soil respiration throughout a year (2017)
  • Author(s): Masaki Uchida
  • Organizer: Ny-Alesund Science Managers Committee
  • Place of Presentation: Clarion Congress Hotel, Prague
  • Int'l Joint Research
• [Remarks] 研究調査等の紹介
  • URL: https://www.instagram.com/mu_arctic/
• [Remarks] 高緯度北極ツンドラ生態系に及ぼす気候変動の影響
  • URL: https://www.researchinsvalbard.no/project/6256
• [Remarks] リサーチマップ
  • URL: https://researchmap.jp/m_uchida
• [Remarks] 国立極地研究所陸上生物研究チーム
  • URL: http://polaris.nipr.ac.jp/~penguin/Terrestrial/index.php
• [Remarks] 生物圏研究グループ 陸上生物研究チーム
  • URL: http://polaris.nipr.ac.jp/~penguin/Terrestrial/index.php
• [Remarks] 北極圏科学観測ディレクトリー
  • URL: http://www.nipr.ac.jp/aerc/document/directory.html
• [Remarks] Research map
  • URL: http://researchmap.jp/m_uchida
• [Remarks] 国立極地研究所生物圏研究グループ 陸上生物研究チーム
  • URL: http://polaris.nipr.ac.jp/~penguin/Terrestrial/index.php