Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 34

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Ecological and genomic profiling of anaerobic methane-oxidizing archaea in a deep granitic environment

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:30 Percentile:93.55(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.

Journal Articles

Deep microbial life in high-quality granitic groundwater from geochemically and geographically distinct underground boreholes

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:18 Percentile:67.66(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$$_{2}$$-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.

Journal Articles

Biogeochemical signals from deep microbial life in terrestrial crust

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:9 Percentile:36.08(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.

JAEA Reports

Mizunami Underground Research Laboratory Project, Annual report for fiscal year 2011

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

JAEA-Review-2013-018.pdf:15.71MB

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.

Journal Articles

Hydrochemical changes associated with construction of Mizunami Underground Research Laboratory

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

Journal Articles

Geomicrobiological properties of ultra-deep granitic groundwater from the Mizunami Underground Research Laboratory (MIU), Central Japan

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:23 Percentile:62.17(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$$_{3}$$$$^{-}$$ and SO$$_{4}$$$$^{2-}$$, were not abundant, while dissolved organic carbon (not including organic acids), CH$$_{4}$$ and H$$_{2}$$ were moderately rich. The most common phylotypes were both related to ${it Thauera}$ 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 ${it Thauera}$ spp. probably owing to the limitation of O$$_{2}$$, NO$$_{3}$$$$^{-}$$ and organic acids.

Oral presentation

Biogeochemical investigations of redox states of groundwater from sedimentary and granitic rocks at the Mizunami Underground Research Laboratory (MIU) site

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.

Oral presentation

Collaborative project of JAEA/AIST on hydrochemical study at MIU construction site, 1; Colloid study

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.

Oral presentation

Collaborative project of JAEA/AIST on hydrochemical study at MIU construction site, 2; Biogeochemical study

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.

Oral presentation

BIO-NANO-GEO Science in deep underground; Approaches at Mizunami Underground Research Laboratory

Suzuki, Yohei*; Fukuda, Akari*; Kozuka, Mariko*; Ishimura, Toyoho*; Tsunogai, Urumu*; Hagiwara, Hiroki; Mizuno, Takashi

no journal, , 

no abstracts in English

Oral presentation

Development the methodology for researching water-rock-microbes interaction in deep underground

Ito, Kazumasa*; Suzuki, Yohei*; Fukuda, Akari*; Kozuka, Mariko*; Mizuno, Takashi; Hagiwara, Hiroki

no journal, , 

no abstracts in English

Oral presentation

Depth variation in microbial community structure and metabolic activities in granitic aquifers at the Mizunami Underground Research Laboratory (MIU), Gifu, Japan

Fukuda, Akari; Kozuka, Mariko*; Aosai, Daisuke; Hagiwara, Hiroki; Mizuno, Takashi; Suzuki, Yohei*

no journal, , 

no abstracts in English

Oral presentation

Hydrogen and carbon isotope geochemistry of freshwater aquifers at the Mizunami Underground Research Laboratory; Implications for ongoing biogeochemical processes in granitic rocks

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$$_{2}$$ 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.

Oral presentation

JAEA/AIST collaborative research project; Development and evaluation of investigation methodology to quantify microbial influences on the deep hydrogeochemical properties

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

Oral presentation

Mizunami Underground Research Laboratory project; Hydrochemical study

Mizuno, Takashi; Hagiwara, Hiroki; Aosai, Daisuke; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari

no journal, , 

no abstracts in English

Oral presentation

Determination of dissolved oxygen concentration in groundwater

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.

Oral presentation

Hydrochemical characterization at Mizunami Underground Research Laboratory; Adequacy assessment of the result of surface-based investigation phase

Mizuno, Takashi; Aosai, Daisuke; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari; Hagiwara, Hiroki

no journal, , 

no abstracts in English

Oral presentation

Metabolic rates of subsurface microorganisms in a hydrogeochemically characterized granitic aquifer system at the Mizunami Underground Research Laboratory (MIU) in Japan

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$$_{2}$$ and NO$$_{3}$$$$^{-}$$ 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.

Oral presentation

Uncertainty evaluation of hydrochemical data; Physico-chemical parameter

Aosai, Daisuke; Hagiwara, Hiroki; Shingu, Shinya; Yamamoto, Yuhei; Fukuda, Akari; Mizuno, Takashi

no journal, , 

no abstracts in English

Oral presentation

Shifts in microbial sulfate reduction to CO$$_{2}$$ reduction depending on groundwater flow characteristics in deep granitic aquifers

Konno, Yuta*; Komatsu, Daisuke*; Nishimura, Shusaku*; Fukuda, Akari; Aosai, Daisuke; Mizuno, Takashi; Nagao, Seiya*; Tsunogai, Urumu*; Suzuki, Yohei*

no journal, , 

no abstracts in English

34 (Records 1-20 displayed on this page)