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Nishimura, Hiroki*; Kozuka, Mariko*; Fukuda, Akari*; Ishimura, Toyoho*; Amano, Yuki; Beppu, Hikari*; Miyakawa, Kazuya; Suzuki, Yohei*
Environmental Microbiology Reports (Internet), 15(3), p.197 - 205, 2023/06
Times Cited Count:0 Percentile:0.01(Environmental Sciences)The family Methanoperedenaceae archaea mediate anaerobic oxidation of methane (AOM). We newly developed a high-pressure laboratory incubation system and investigated groundwater from 214- and 249-m deep boreholes at Horonobe Underground Research Laboratory, Japan, where the high and low abundances of
Methanoperedenaceae archaea have been revealed, respectively. We incubated the samples amended with or without amorphous Fe(III) and
C-labelled methane at an in-situ pressure of 1.6 MPa. After three to seven-day incubation, AOM activities were not detected from the 249-m sample but from the 214-m sample. The AOM rates were 93.7
40.6 and 27.7
37.5 nM/day with and without Fe(III) amendment. Suspended particulates were not visible in the 249-m sample on the filter, while they were abundant and contained amorphous Fe(III) and Fe(III)-bearing phyllosilicates in the 214-m sample. This supports the in-situ activity of Fe(III)-dependent AOM in the deep subsurface borehole.
Ino, Kohei*; Hernsdorf, A. W.*; Konno, Yuta*; Kozuka, Mariko*; Yanagawa, Katsunori*; Kato, Shingo*; Sunamura, Michinari*; Hirota, Akinari*; Togo, Yoko*; Ito, Kazumasa*; et al.
ISME Journal, 12(1), p.31 - 47, 2018/01
Times Cited Count:45 Percentile:91.8(Ecology)In this study, we found the dominance ofanaerobic methane-oxidizing archaea in groundwater enriched in sulfate and methane from a 300-m deep underground borehole in granitic rock.
Ino, Kohei*; Konno, Yuta*; Kozuka, Mariko*; Hirota, Akinari*; Togo, Yoko*; Fukuda, Akari*; Komatsu, Daisuke*; Tsunogai, Urumu*; Tanabe, Akifumi*; Yamamoto, Satoshi*; et al.
Environmental Microbiology Reports (Internet), 8(2), p.285 - 294, 2016/04
Times Cited Count:24 Percentile:66.62(Environmental Sciences)To understand the subsurface biosphere, borehole investigation was conducted for 300-m deep granitic rocks at the Mizunami underground research laboratory, Japan. The initial biomass was the highest with the flourish of aerobic H-oxidizing Hydrogenophaga spp., whereas an uncultivated lineage of the phylum Nitrospirae became predominant after three years with decreasing biomass. The common occurrence of many species of Nitrospirae and Chlorobi phyla at the geographically distinct sites and the exclusive detection of their phylogenetically related environmental sequences from deep groundwaters and terrestrial hot springs, suggest that these bacteria are indigenous and potentially adapted to the deep terrestrial subsurface.
Suzuki, Yohei*; Konno, Yuta*; Fukuda, Akari*; Komatsu, Daisuke*; Hirota, Akinari*; Watanabe, Katsuaki*; Togo, Yoko*; Morikawa, Noritoshi*; Hagiwara, Hiroki; Aosai, Daisuke*; et al.
PLOS ONE (Internet), 9(12), p.e113063_1 - e113063_20, 2014/12
Times Cited Count:11 Percentile:35.78(Multidisciplinary Sciences)We present multi-isotopic evidence of microbially mediated sulfate reduction in a granitic aquifer, a representative of the terrestrial crust habitat. Deep groundwater of meteoric origin was collected from underground boreholes drilled into the Cretaceous Toki granite, central Japan. A large sulfur isotopic fractionation of 20-60 permil diagnostic to microbial sulfate reduction is associated with the investigated groundwater containing sulfate below 0.2 mM. In contrast, a small carbon isotopic fractionation ( 30 permil) is not indicative of methanogenesis. Our results demonstrate that the deep biosphere in the terrestrial crust is metabolically active and playing a crucial role in the formation of reducing groundwater even under low energy fluxes.
Kunimaru, Takanori; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Ishibashi, Masayuki; Sasao, Eiji; Hikima, Ryoichi; Tanno, Takeo; Sanada, Hiroyuki; et al.
JAEA-Review 2013-018, 169 Pages, 2013/09
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in 2011 fiscal year. This report shows the results of the investigation, construction and collaboration studies in fiscal year 2011, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.
Mizuno, Takashi; Aosai, Daisuke; Shingu, Shinya; Hagiwara, Hiroki; Yamamoto, Yuhei; Fukuda, Akari
Nihon Genshiryoku Gakkai Wabun Rombunshi, 12(1), p.89 - 102, 2013/03
no abstracts in English
Fukuda, Akari*; Hagiwara, Hiroki; Ishimura, Toyoho*; Kozuka, Mariko*; Ioka, Seiichiro*; Amano, Yuki; Tsunogai, Urumu*; Suzuki, Yohei*; Mizuno, Takashi
Microbial Ecology, 60(1), p.214 - 225, 2010/05
Times Cited Count:28 Percentile:65.73(Ecology)To better understand the geochemical and microbiological relationships, we characterized granitic groundwater collected from a 1,148 to 1,169 -m deep borehole interval at the Mizunami Underground Research Laboratory site, Japan, in 2005 and 2008. Geochemical analyses of the groundwater samples indicated that major electron acceptors, such as NO and SO
, were not abundant, while dissolved organic carbon (not including organic acids), CH
and H
were moderately rich. The most common phylotypes were both related to
spp., the cultivated members of which can utilize minor electron donors, such as aromatic and aliphatic hydrocarbons. Geomicrobiological results suggest that deep granitic groundwater has been stably colonized by
spp. probably owing to the limitation of O
, NO
and organic acids.
Fukuda, Akari*; Suzuki, Yohei*; Ito, Kazumasa*; Mizuno, Takashi; Amano, Yuki; Hagiwara, Hiroki; Hama, Katsuhiro
no journal, ,
This study was aimed to understand the control system and the process of redox system in deep groundwater. As the result of chemical study of groundwater, it is revealed that succniate was highly enriched in groundwater from Toki Formation (up to 81 mg/L). This result suggests that succinate is one of major electron donors that can fuel metabolic activities.
Mizuno, Takashi; Suzuki, Yohei*; Fukuda, Akari*; Hagiwara, Hiroki; Ito, Kazumasa*
no journal, ,
JAEA and AIST has been conducting collaborative work on hydrochemical study at MIU construction site. The aim of this collaborative study is to establish the methodology for investigation, analysis and evaluation of colloid/organics/microbes study. This paper reports that the colloid study. As the result, it is suggested that some metal components are existing as non-dissolved solid.
Fukuda, Akari*; Hagiwara, Hiroki; Ishimura, Toyoho*; Kozuka, Mariko*; Ito, Kazumasa*; Tsunogai, Urumu*; Suzuki, Yohei*; Mizuno, Takashi
no journal, ,
JAEA and AIST have been conducting collaborative work on hydrochemical study at MIU construction site. The aim of this collaborative study is to establish the methodology for investigation, analysis and evaluation of colloid/organics/microbes study. This paper reports the biogeochemical study. As the result, it is suggested that groundwater taken from deeper part (1150m depth) is relatively oxidized.
Suzuki, Yohei*; Fukuda, Akari*; Kozuka, Mariko*; Ishimura, Toyoho*; Tsunogai, Urumu*; Hagiwara, Hiroki; Mizuno, Takashi
no journal, ,
no abstracts in English
Ito, Kazumasa*; Suzuki, Yohei*; Fukuda, Akari*; Kozuka, Mariko*; Mizuno, Takashi; Hagiwara, Hiroki
no journal, ,
no abstracts in English
Fukuda, Akari; Kozuka, Mariko*; Aosai, Daisuke; Hagiwara, Hiroki; Mizuno, Takashi; Suzuki, Yohei*
no journal, ,
no abstracts in English
Konno, Yuta*; Fukuda, Akari; Kozuka, Mariko*; Komatsu, Daisuke*; Tsunogai, Urumu*; Aosai, Daisuke; Mizuno, Takashi; Suzuki, Yohei*
no journal, ,
Our knowledge of biogeochemical processes mediated in those associated with freshwater should be integrated. We collected the groundwater samples from 200 m to 1150 m depths below ground level at Mizunami Underground Research Laboratory located in central Japan. We measured the concentration and both hydrogen and carbon isotopic compositions of dissolved methane, total inorganic carbon (TIC) and molecular hydrogen. The origin of methane could be speculated to be not biogenic CO reduction or acetate fermentation but thermogenic or abiogenic. In contrast, C1/C2+C3 ratios supported biogenic methane production. The 300 m deep samples were enriched in hydrogen and acetate and depleted in sulfate, which is characteristic of acetogenesis. From these results, it is suggested that the production of acetate rather than methane could be dominant biogeochemical processes in the reducing portions of freshwater aquifers in granitic rocks.
Fukuda, Akari; Mizuno, Takashi; Aosai, Daisuke; Hagiwara, Hiroki; Yamamoto, Yuhei; Shingu, Shinya; Ito, Kazumasa*; Suzuki, Yohei*; Kozuka, Mariko*; Konno, Yuta*
no journal, ,
no abstracts in English
Mizuno, Takashi; Hagiwara, Hiroki; Aosai, Daisuke; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari
no journal, ,
no abstracts in English
Aosai, Daisuke; Hagiwara, Hiroki; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari; Suzuki, Yohei*; Mizuno, Takashi
no journal, ,
The hydrochemical investigation focused on the deep groundwater is generally conducted by using groundwater samples taken from deep boreholes. It is impossible to avoid the contamination of the groundwater from drilling fluid during borehole drilling. Although the groundwater samples taken from borehole is contaminated with drilling fluid, the ratio of the contamination can be evaluated based on the tracer (e.g. fluorescence dye) concentration that is added to the drilling fluid, quantitatively. This methodology can apply to quantitative determination of major element and isotopic composition in groundwater by extrapolating. However, it is not argued about the applicability of this methodology for the quantitative and/or qualitative determination of minor elements, microbes, organics and colloid in groundwater. This study aimed to understand the impact caused by borehole drilling to hydrochemical properties focused on the concentration of dissolved oxygen (DO). As the result, some knowledge was obtained as follows; (1) Oxygen intruded into in-situ groundwater during drilling even though borehole was artesian condition. (2) The contamination of DO during borehole drilling can be monitored by measurement of DO concentration. (3) It is recommended that DO concentration should be measured by Winkler method in addition to common electrode method for obtaining the reliable result.
Mizuno, Takashi; Aosai, Daisuke; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari; Hagiwara, Hiroki
no journal, ,
no abstracts in English
Fukuda, Akari; Kozuka, Mariko*; Konno, Yuta*; Aosai, Daisuke; Hagiwara, Hiroki; Mizuno, Takashi; Suzuki, Yohei*
no journal, ,
To quantify microbial influences on the hydrogeochemistry of a 99-1169-m deep granitic aquifer system, we developed methodology for sensitive measurements of a variety of aerobic and anaerobic metabolic activities. Briefly, microbial cells were ca. 30-fold concentrated in groundwater by filtration to incubate with electron acceptors. Aerobic respiration was more than 400 umol/L/year at depths of 99 and 175 m and decreased with increasing depth down to 36 umol/L/year at a depth of 1169 m. Nitrate respiration increased from 99 to 308 m (4.3 to 37 umol/L/year) and decreased with increasing depth down to 0.20 umol/L/year. Sulfate respiration ranging from 1.4 to 3.2 umol/L/year was detected only at depths above 200 m. The depletion of O and NO
and a gradual decrease in sulfate with increasing depth in the granitic aquifer could be attributed to microbial respirations at rates clarified in this study. Our research was partially founded by Nuclear and Industry Safety Agency.
Aosai, Daisuke; Hagiwara, Hiroki; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari; Mizuno, Takashi
no journal, ,
no abstracts in English