Dataset Information

Hadal biosphere: insight into the microbial ecosystem in the deepest ocean on Earth.

ABSTRACT: Hadal oceans at water depths below 6,000 m are the least-explored aquatic biosphere. The Challenger Deep, located in the western equatorial Pacific, with a water depth of ?11 km, is the deepest ocean on Earth. Microbial communities associated with waters from the sea surface to the trench bottom (0?10,257 m) in the Challenger Deep were analyzed, and unprecedented trench microbial communities were identified in the hadal waters (6,000?10,257 m) that were distinct from the abyssal microbial communities. The potentially chemolithotrophic populations were less abundant in the hadal water than those in the upper abyssal waters. The emerging members of chemolithotrophic nitrifiers in the hadal water that likely adapt to the higher flux of electron donors were also different from those in the abyssal waters that adapt to the lower flux of electron donors. Species-level niche separation in most of the dominant taxa was also found between the hadal and abyssal microbial communities. Considering the geomorphology and the isolated hydrotopographical nature of the Mariana Trench, we hypothesized that the distinct hadal microbial ecosystem was driven by the endogenous recycling of organic matter in the hadal waters associated with the trench geomorphology.

SUBMITTER: Nunoura T

PROVIDER: S-EPMC4371994 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Hadal biosphere: insight into the microbial ecosystem in the deepest ocean on Earth.

Nunoura Takuro T Takaki Yoshihiro Y Hirai Miho M Shimamura Shigeru S Makabe Akiko A Koide Osamu O Kikuchi Tohru T Miyazaki Junichi J Koba Keisuke K Yoshida Naohiro N Sunamura Michinari M Takai Ken K

Proceedings of the National Academy of Sciences of the United States of America 20150223 11

Hadal oceans at water depths below 6,000 m are the least-explored aquatic biosphere. The Challenger Deep, located in the western equatorial Pacific, with a water depth of ∼11 km, is the deepest ocean on Earth. Microbial communities associated with waters from the sea surface to the trench bottom (0∼10,257 m) in the Challenger Deep were analyzed, and unprecedented trench microbial communities were identified in the hadal waters (6,000∼10,257 m) that were distinct from the abyssal microbial commun ...[more]

PMID: 25713387

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Dataset Information

Hadal biosphere: insight into the microbial ecosystem in the deepest ocean on Earth.

Publications

Hadal biosphere: insight into the microbial ecosystem in the deepest ocean on Earth.

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