いま取り組んでいること These days


1.Impact of torrential rainfall on the ecosystem of river and its estuary; A study in Kanogawa riverine system in Izu peninsula

→ https://wwp.shizuoka.ac.jp/kanogawa/ へリンク


2.Microbes in groundwater of deep biosphere



(1)A study in deep biosphere at the foot of Mt. Fuji

In addition to the hydrogeological understanding on the path of groundwater in deep biosphere, we present a method to estimate the path of groundwater using microbial DNA. If you retrieve thermophilic DNA from the examined water, this suggest the water is at least partially transported from the environment exceeding 40 ℃. This method is well applied to elucidate the changes in the route of groundwater in in the case of torrential rainfall. This may lead us to forecast the land slide caused by torrential rainfall as if exceeding 200-300 mm per event which fills up the the surface aquifer.

【Original papers】

1)Microbes in groundwater of a volcanic mountain, Mt. Fuji; 16S rDNA phylogenetic analysis as a possible indicator for the transport routes of groundwater. T. Segawa, A. Sugiyama, T. Kinoshita, R. Sohrin, T. Nakano, K. Nagaosa, D. Greenidge, K. Kato, Geomicrobiol. J., 32: 677-688 (2015).

2)Tracking the direct impact of rainfall on groundwater at Mt. Fuji by multiple analyses including microbial DNA. Ayumi Sugiyama,Suguru Masuda,Kazuyo Nagaosa,Maki Tsujimura, and Kenji Kato, Biogeosciences, 15:721-732 (2018).

3)ドローンを用いた河川水温の測定による湧水箇所の探査, 松本ほか(加藤は責任著者)陸水学雑誌,83,141-148 (2022)

4)”Triple junction hydrogeology: Revisiting Mt. Fuji’s groundwater origins with novel tracers”. O. Schilling, .., K.Kato, Nature Water (in review, 2022)


私たちが向き合わなければならない最大の環境問題の一つ、負の環境遺産である放射性廃棄物の地下圏への処分に微生物が影響するか研究を始めようと微生物生態学会の先輩Fさんに誘われたのが2005年頃。その後、北海道天塩郡幌延町に設置された深地層研究所の掘削孔を使った微生物研究に取り組み(論文 3),4))、さらに廃棄された放射性物質の地下水中での拡散問題に微生物がどのように関わるかをロシア側研究者との7年にわたる共同研究で明らかにした研究をようやく2020年に書籍として公開することができた(Book 1))。その縁で、福島大学環境放射能研究所の研究者とチェルノービル(チェルノブイリ)研究の出版にも協力させていただいた(Book 2))。未だ候補地が決まらない我が国の放射性廃棄物処分問題は、未来の原告(子供達とさらに次やその次の世代を担う人たち)に向けて私たちは未だ何もなし得ていない。ゴミ問題と同様に、海外に処分を“輸出”するようなことがあって良いものだろうか?

(2)Microbial study relating to the construction of radioactive waste repository in deep subsurface environment

One of the most critical issues in the environment for the earth is no doubt how do we treat radioactive waste produced throughout the 20th century. However, our understanding on the target place, deep biosphere, is still insufficient in particular from the biological stand point. The deep subsurface environment is the world for microbes. We have carried out over 7 years collaboration with Russian scientists on the radioactive groundwater contamination in Ural, which is presented by a Book mentioned below. Concerned the case for sedimentary rock in Japan, we study in the area of Horonobe in Hokkaido, and some pares have been published shown below. Papers in Japanese are reviews.


1)”Behavior of Radionuclides in the Environment I. Function of Particles in Aquatic System.” Editors:  Kenji. Kato, Alexei Konoplev, Stepan N. Kalmykov, Springer-Nature, 225pp. (https://www.springer.com/jp/book/9789811506789#aboutAuthors

2)”Behavior of Radionuclides in the Environment II Chernobyl” Editors:  Alexei Konoplev, Kenji.Kato, Stepan N. Kalmykov, Springer-Nature, 443pp.(2020) https://doi.org/10.1007/978-981-15-3568-0

【Original papers】

3)Unique distribution of deep groundwater bacteria constrained by geological setting. K. Kato, K. Nagaosa, H. Kimura, C. Katsuyama, K. Hama, T. Kunimaru, U. Tsunogai, K. Aoki, Environmental Microbiology Report, 1:569-574 (2009).

4)Occurrence and potential activity of denitrifiers and methanogens in groundwater at 140 m depth in Pliocene diatomaceous mudstone of northern Japan. C. Katsuyama, H. Nashimoto, K. Nagaosa,  T. Ishibashi , K. Furuta , T. Kinoshita , H. Yoshikawa , K. Aoki, T. Asano , Y. Sasaki , R. Sohrin , D. Komatsu , U. Tsunogai , H. Kimura, Y. Suwa, K. Kato, FEMS Microbiology Ecology, 86: 532-543 (2013).

【Related papers】

5)Comparison of Solid-Water Partitions of Radiocesium in River Waters in Fukushima and Chernobyl Areas.Yoshio Takahashi, Qiaohui Fan, Hiroki Suga, Kazuya Tanaka, Aya Sakaguchi, Yasuo Takeichi, Kanta Ono, Kazuhiko Mase, Kenji Kato & Vladimir V. Kanivets. Scientific Reports 7,Article number:12407.  doi:10.1038/s41598-017-12391-7 (2017)

6)Sorption behavior of Np(V) on microbe pure culture and consortia. Toshihiko Ohnuki, Naofumi Kozai, Fuminori Sakamoto, Satoshi Utsunomiya, Kenji Kato, Chemistry Letters,46:771-774 (2017) doi: 10.1246/cl.170068.(2017).

7)Ultramicrobacteria from Nitrate- and Radionuclide-Contaminated Groundwater. Tamara Nazina,…,Kenji Kato, Sustainability, 12 1239-doi:10.3390/su12031239.(2020).

8)北海道幌延地域沿岸部の深層地下水における微生物分布の特,杉山 歩井原 哲夫辻村 真貴永翁 一代加藤 憲二丸井 敦尚, 水文・水資源学会 2019 年 32 巻 5 号 p. 245-254, https://doi.org/10.3178/jjshwr.32.245

9)地下水流動系という視点から見る微生物動態研究の課題と展望、杉山歩、辻村真貴, 加藤憲二、地下水学会誌、62(3):431-448(2020).


10)深部地下水を対象とした微生物基礎データの収集、杉山、井原、永翁、辻村、加藤、地盤工学ジャーナル, 16,13-21 (2021).


Prof. Emeritus Kenji Kato
Adress:Shizuoka University
836 Ohya, Suruga-ku, Shizuoka,
422-8529, Japan

静岡大学 理学部 加藤憲二研究室
静岡県静岡市駿河区 大谷836
理学部 C棟 401・402号室