Impact of permafrost degradation on the discharge of dissolved iron in the Amur River basin

• Project/Area Number: 15H05208
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Hokkaido University
• Principal Investigator: SHIRAIWA TAKAYUKI 北海道大学, 低温科学研究所, 准教授 (90235739)
• Co-Investigator(Kenkyū-buntansha): 長尾 誠也 金沢大学, 環日本海域環境研究センター, 教授 (20343014) ; 楊 宗興 東京農工大学, その他の研究科, 教授 (50260526) ; 大西 健夫 岐阜大学, 応用生物科学部, 准教授 (70391638)
• Research Collaborator: TASHIRO Yuto ; KUBO Takumi
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥14,170,000 (Direct Cost: ¥10,900,000、Indirect Cost: ¥3,270,000); Fiscal Year 2017: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000); Fiscal Year 2016: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2015: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
• Keywords: 溶存鉄 / 永久凍土 / 湿地 / アムール川 / マリ / 気候変動 / ロシア極東 / 河畔域 / 魚附林 / オホーツク海 / 溶存鉄濃度 / 土地利用 / 水質

Outline of Final Research Achievements

We investigated the Tyrma river basin of the Amur river from 2015 to 2017 in order to clarify possible cause of the rapid increase in dissolved iron of the Amur river in the late 1990s. Our 6-times field survey led to the findings of unique landscape called "mari" where sparse larch forest underlain by sphagnum vegetation. The "mari" is found to support sporadic permafrost and supplies significant amount of dissolved iron to its river. The "mari" is found to be developed in riparian zone of the river system by the analyses of indices like NDVI, NDWI and NDSI based on LANDSAT spectral data.

We speculate the cause of rapid increase in dissolved iron concentration of the Amur river in the late 1990s were caused by melting of sporadic permafrost which resulted in the extension of redox condition in the upper part of the Amur river.

Research Products

• [Int'l Joint Research] ロシア科学アカデミー極東支部 水・生態学研究所(ロシア連邦)
• [Int'l Joint Research] ロシア科学アカデミー極東支部 水・生態問題研究所(ロシア連邦)
• [Int'l Joint Research] ロシア科学アカデミー極東支部 水生態問題研究所(ロシア連邦)
• [Journal Article] アムール川流域における溶存鉄生成メカニズムのモデル化 (2016)
  • Author(s): 大西健夫・楊宗興・白岩孝行・長尾誠也
  • Journal Title: 低温科学 Volume: 74 Pages: 13-20
  • Peer Reviewed
• [Presentation] ソフロン川流域湿地における永久凍土活動層厚の時系列変動推定 (2018)
  • Author(s): 大西健夫・田代悠人・久保匠・楊宗興・白岩孝行
  • Organizer: 日本地理学会
• [Presentation] 永久凍土の季節的変動が溶存鉄の挙動に与える影響 (2018)
  • Author(s): 田代悠人・楊宗興・大西健夫・白岩孝行・久保匠
  • Organizer: 日本地理学会
• [Presentation] 衛星リモートセンシングを用いたアムール川流域における永久凍土の探査 (2018)
  • Author(s): 久保匠・白岩孝行・大西健夫・田代悠人・楊宗興
  • Organizer: 日本地理学会
• [Presentation] Linking Dynamics of Permafrost and Dissolved Iron Production in the Amur River basin (2017)
  • Author(s): Takeo Onishi, Vladimir Shamov, Takayuki Shiraiwa, Muneoki Yoh, Seiya Nagao, Vladimir I. Kim, Vladimir P. Shesterkin, Takumi Kubo, Yuto Tashiro
  • Organizer: The 2nd Asian Conference on Permafrost 2017
  • Int'l Joint Research
• [Presentation] 極東ロシアにおける永久凍土の季節的誘拐が鉄の挙動に与える影響：土壌間隙水及び河川の溶存鉄濃度7月-10月観測結果 (2017)
  • Author(s): 田代悠人、楊宗興、白岩孝行、大西健夫、Vradimir. I. Kim、Vradimir. P. Systerkin、久保匠
  • Organizer: 日本陸水学会
• [Presentation] A new possible source of dissolved iron in the Amur River basin. (2016)
  • Author(s): Shiraiwa, T., Yoh, M., Onishi,T., Tashiro, Y., Kubo, T., Kim, V., Shesterkin, V. and Antonov, A.
  • Organizer: International Conference on Resources, Environment and Regional Sustainable Development in Northeast Asia
  • Place of Presentation: Vladivostok (Russia)
  • Year and Date: 2016-10-10
  • Int'l Joint Research
• [Presentation] Abrupt rise of dissolved iron concentration in the late 1990s' and possibility of influence of seasonal permafrost dynamics in the Amur River basin (2016)
  • Author(s): Onishi T., V. V. Shamov, T. Kubo, T. Shiraiwa, Y. Tashiro, M. Yoh, V. I. Kim, and V. P. Shesterkin
  • Organizer: International Conference on Water Resources and Problems of Their Sustainable Use
  • Place of Presentation: Khabarovsk (Russia)
  • Year and Date: 2016-09-28
  • Int'l Joint Research
• [Presentation] 水質調査から示される丘陵地の溶存鉄供給に対する機能 (2016)
  • Author(s): 田代悠人・楊宗興
  • Organizer: 日本地球惑星科学連合2016年大会
  • Place of Presentation: メッセ国際会議場（千葉県千葉市）
  • Year and Date: 2016-05-22