Dynamics of radiocesium deposited in forests and within forest trees

• Project/Area Number: 15K11950
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: 復興農学
• Research Institution: The University of Tokyo
• Principal Investigator: Masumori Masaya 東京大学, 大学院農学生命科学研究科(農学部), 講師 (50282702)
• Co-Investigator(Kenkyū-buntansha): 丹下 健 東京大学, 大学院農学生命科学研究科(農学部), 教授 (20179922)
• Project Period (FY): 2015-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2019: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2017: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2016: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2015: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: 原発事故 / スギ / コナラ / 交換性カリウム / 放射能低減 / 福島 / クヌギ / 塩化加里 / 福島県 / ミズナラ / 放射性セシウム / 林木 / 幹材 / 汚染地域 / 樹皮 / 葉枯らし / 除染

Outline of Final Research Achievements

Dynamics of radiocesium within tree in the forest polluted by The accident of Fukushima Dai-ichi Nuclear Power Plant were investigated to enhance the resumption of forestry, local economy and consequently the restoration of local community of the affected area in wooded western Fukushima, Japan.
Distributions of radiocesium within trunk of Sugi cedar were analyzed by radiographic imaging with storage phosphor screens. The results suggest that some of the radiocesium in the xylem is soluble in water and migrates with the water movement of the apoplastic during wood drying after felling.
Radiocesium in konara oak, a hardwood that can be used for mushroom logs, was also investigated. It was found that applying potassium fertilisers to the ground surface and increasing the amount of exchangeable potassium in the soil inhibited the absorption of radiocesium by newly planted Quercus crispula.

Academic Significance and Societal Importance of the Research Achievements

スギ幹材内の放射性セシウムが水分の移動とともない移動することが明らかになった。伐採してから木材として利用するまでの間に放射能分布が変化することを意味している。またシイタケ原木林においては経根吸収する放射性セシウム量が土壌条件に影響される知見が得られた。いずれも汚染地域の木材利用を検討する上での重大な知見である。

Research Products

• [Journal Article] Effect of exchangeable and non-exchangeable potassium in soil on cesium uptake by Quercus serrata seedlings (2023)
  • Author(s): Kobayashi R, Masumori M, Tange T, Tanoi K, Kobayashi NI, Miura S
  • Journal Title: Agricultural implications of the Fukushima nuclear accident (IV) Volume: - Pages: 171-184
  • DOI: 10.1007/978-981-19-9361-9_15
  • ISBN: 9789811993602, 9789811993619
  • Open Access / Int'l Joint Research
• [Journal Article] Challenge to resume production of mushroom bed logs by potassium fertilizer application (2023)
  • Author(s): Masumori M, Kobayashi NI, Tanoi K, Nihei N, Miura S, Kanasashi T
  • Journal Title: Agricultural implications of the Fukushima nuclear accident (IV) Volume: - Pages: 197-202
  • DOI: 10.1007/978-981-19-9361-9_17
  • ISBN: 9789811993602, 9789811993619
  • Open Access / Int'l Joint Research
• [Journal Article] クヌギ植栽地におけるカリウム施用等土壌処理と植栽苗の放射性セシウム吸収 (2021)
  • Author(s): 益守眞也・平出政和・小林奈通子・田野井慶太朗・三浦覚
  • Journal Title: 日本森林学会学術講演集 Volume: 132 Pages: 193-193
  • NAID: 130008117861
  • Open Access
• [Presentation] クヌギ植栽地におけるカリウム施用等土壌処理と植栽苗の放射性セシウム吸収 (2021)
  • Author(s): 益守眞也・平出政和・小林奈通子・田野井慶太朗・三浦覚
  • Organizer: 第１３２回日本森林学会大会
• [Presentation] Mobile radiocesium in felled logs of Sugi cedar (2019)
  • Author(s): Masumori M., Sakai T., Tange T. and Nogawa N.
  • Organizer: XXV IUFRO World Congress 2019
  • Int'l Joint Research
• [Presentation] Suppression of cesium uptake in Konara oak using potassium - for a revival of mushroom production in Fukushima (2019)
  • Author(s): Riona Kobayashi, NatsukoI. Kobayashi, Masaya Masumori, Keitaro Tanoi, Takeshi Tange , Kensuke Fukuda, Satoru Miura
  • Organizer: XXV IUFRO World Congress 2019
  • Int'l Joint Research
• [Presentation] 乾燥に伴うスギ材中の放射性セシウムの移動 (2018)
  • Author(s): 酒井哲郎，益守眞也，丹下健
  • Organizer: 第１２９回日本森林学会大会
• [Presentation] グローバルフォールアウトCs-137を利用したコナラの移行係数推定 (2016)
  • Author(s): 三浦覚・益守眞也・高田大輔・関谷信人・成田義人・新田響平・中島春樹・相浦英春・小谷二郎・小倉晃・田野井慶太朗・中西友
  • Organizer: 第126回日本森林学会大会
  • Place of Presentation: 神奈川県 日本大学生物資源科学部
  • Year and Date: 2016-03-27
• [Presentation] 数十年前に日本全国の森林域に降下した大気圏核実験由来の放射性セシウムの分布 (2015)
  • Author(s): 三浦覚,青山道夫,伊藤江利子, 志知幸治,高田大輔,益守眞也, 関谷信人,小林奈通子,高野直人,金子真司, 田野井慶太朗, 中西友子
  • Organizer: 日本地球惑星科学連合2015年大会
  • Place of Presentation: 千葉県 幕張メッセ
  • Year and Date: 2015-05-24
  • Int'l Joint Research
• [Presentation] Towards prediction of redistribution of fallout radiocesium on forested area discharged from Fukushima Nuclear Power Plant (2015)
  • Author(s): Satoru Miura, Michio Aoyama, Eriko Ito, Koji Shichi, Daisuke Takata, Masumori Masaya, Nobuhito Sekiya, Natsuko Kobayashi, Naoto Takano, Shinji Kaneko, Keitaro Tanoi, and Tomoko Nakanishi
  • Organizer: European Geosciences Union General Assembly 2015
  • Place of Presentation: Vienna，Austria
  • Year and Date: 2015-04-12
  • Int'l Joint Research
• [Book] Agricultural Implications of the Fukushima Nuclear Accident (2015)
  • Author(s): Nakanish T.T. and Tanoi K. eds
  • Total Pages: 263
  • Publisher: Springer