Japan Geoscience Union Meeting 2015

Presentation information

Poster

Symbol B (Biogeosciences) » B-CG Complex & General

[B-CG28] Interrelation between Life, Water, Mineral, and Atmosphere

Tue. May 26, 2015 6:15 PM - 7:30 PM Convention Hall (2F)

Convener:*Fumito Shiraishi(Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University), Tsubasa Otake(Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University), Yohey Suzuki(Graduate School of Science, The University of Tokyo), Ken Takai(Extremobiosphere Research Center, Japan Agency for Marine-Earth Science & Technology), Yuichiro Ueno(Department of Earth and Planetary Sciences, Tokyo Institute of Technology), Takeshi Naganuma(Graduate School of Biosphere Science), Takeshi Kakegawa(Graduate School of Science, Tohoku University), Tadashi Yokoyama(Department of Earth and Space Science, Graduate School of Science, Osaka University), Kentaro Nakamura(Precambrian Ecosystem Laboratory (PEL), Japan Agency for Marine-Earth Science and Technology (JAMSTEC))

6:15 PM - 7:30 PM

[BCG28-P07] Microbial zonation observed on travertines: a case in northern Sumatra

*Chiya SUGIHARA1, Katsunori YANAGAWA1, Akihiro KANO1, Chizuru TAKASHIMA2, Tomoyo OKUMURA3, Agung HARIJOKO4 (1.Kyushu University, 2.Saga University, 3.JAMSTEC, 4.Gadjah Mada University)

Travertines, carbonate developed in calcareous hot springs, often exhibit laminated structures of the ancient stromatolites. Cyanobacteria play a central role to form laminated structures (e.g., Okumura et al. 2013), other microbial groups can be associated with the travertines. An example is the case in Dolok Tinggi Raja in northern Sumatra. Distinct microbial zonation was observed along the flow passage of the two major spring sites. At proximal locations besides the hot spring at 60 degrees, sulfur turf inhabited a high concentration of hydrogen sulfide. Purple sulfur bacteria become dominant from several meters below the spring. The sulfur bacteria that form a biofilm of 1 mm thick have potential to develop laminated structure. Water chemistry indicates that aragonite precipitation was activated from this location. In the lower portion of the flow passage where the temperature is declined below 50 degree, microbial community was replaced by cyanobacteria that formed a biofilm of similar thickness. Decreases in hydrogen sulfide and temperature are responsible factors for this microbial zonation.