Metal accumulation and retention mechanism in lichen, and applicability of radioactive fallout evaluation
Project/Area Number |
16K12627
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Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Multi-year Fund |
Research Field |
Modeling and technologies for environmental conservation and remediation
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Research Institution | Japan Atomic Energy Agency |
Principal Investigator |
Dohi Terumi 国立研究開発法人日本原子力研究開発機構, 福島研究開発部門 福島研究開発拠点 福島環境安全センター, 技術副主幹 (50469821)
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Co-Investigator(Kenkyū-buntansha) |
高橋 嘉夫 東京大学, 大学院理学系研究科(理学部), 教授 (10304396)
大村 嘉人 独立行政法人国立科学博物館, 植物研究部, 研究主幹 (40414362)
町田 昌彦 国立研究開発法人日本原子力研究開発機構, システム計算科学センター, 研究主席 (60360434)
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Project Period (FY) |
2016-04-01 – 2019-03-31
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Project Status |
Completed (Fiscal Year 2018)
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Budget Amount *help |
¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2018: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2017: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2016: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
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Keywords | 地衣類 / セシウム / ストロンチウム / ヨウ素 / 第一原理計算 / EXAFS / 環境モニタリング / アルカリ金属 / 環境モニタリング材料 / 金属元素保持特性 / 微量元素分析 |
Outline of Final Research Achievements |
Lichens are known to accumulate and retain metals and radionuclides. However, little is known about these mechanisms. Here we studied the relationships between their morphology or physiological characteristics and metal accumulation, and retention. We focused on elements; Cs, Sr, I. An absorption experiments of these elements were carried out. The distributions of the elements in lichen tissues were observed by electron microscope. In addition, chemical state analysis and model calculation were combined to investigate factors related to accumulation. As the results, we found that Cs and Sr distributed in cortex mainly. It was suggested that the difference between the morphology and the amounts of Cs and Sr was not shown in relative species. The binding stabilities between lichen secondary metabolites and Cs were also evaluated. The high stability was shown in usnic acid under alkaline conditions, though the stabilities of all metabolites were similar under neutral conditions.
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Academic Significance and Societal Importance of the Research Achievements |
地衣類中の面積あたりの放射性Cs量はこれまで実環境下の試料で形態の違い(生殖器官の密度)が要因との議論もなされてきたが、対象種については栄養繁殖器官による形態差が表面積を左右しない可能性が示されたのは大きな成果であった。地衣体組織内部のCsおよびSrの主な分布状況を初めて視覚的に示すことができたことも重要な成果である。さらにCsと地衣類の二次代謝物や細胞壁成分との錯体安定性の評価結果を示すことができたのは世界で初めての成果であり、化学状態分析結果と組み合わせた評価によってより具体的な保持状態の検討が進展するものと期待される。
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Report
(4 results)
Research Products
(6 results)