UNIGE document Scientific Article
previous document  unige:102866  next document
add to browser collection
Title

Microbial community composition along a 50 000-year lacustrine sediment sequence

Authors
Horn, Fabian
Kallmeyer, Jens
Orsi, William D
Published in FEMS Microbiology Ecology. 2018, vol. 94, no. 4
Abstract For decades, microbial community composition in subseafloor sediments has been the focus of extensive studies. In deep lacustrine sediments, however, the taxonomic composition of microbial communities remains undercharacterized. Greater knowledge on microbial diversity in lacustrine sediments would improve our understanding of how environmental factors, and resulting selective pressures, shape subsurface biospheres in marine and freshwater sediments. Using high-throughput sequencing of 16S rRNA genes across high-resolution climate intervals covering the last 50 000 years in Laguna Potrok Aike, Argentina, we identified changes in microbial populations in response to both past environmental conditions and geochemical changes of the sediment during burial. Microbial communities in Holocene sediments were most diverse, reflecting a layering of taxa linked to electron acceptors availability. In deeper intervals, the data show that salinity, organic matter and the depositional conditions over the Last Glacial-interglacial cycle were all selective pressures in the deep lacustrine assemblage resulting in a genetically distinct biosphere from the surface dominated primarily by Bathyarchaeota and Atribacteria groups. However, similar to marine sediments, some dominant taxa in the shallow subsurface persisted into the subsurface as minor fraction of the community. The subsequent establishment of a deep subsurface community likely results from a combination of paleoenvironmental factors that have shaped the pool of available substrates, together with substrate depletion and/or reworking of organic matter with depth.
Identifiers
Full text
Structures
Research group Limnology and Geomicrobiology
Project FNS: 200020-119931 8
Citation
(ISO format)
VUILLEMIN, Aurèle et al. Microbial community composition along a 50 000-year lacustrine sediment sequence. In: FEMS Microbiology Ecology, 2018, vol. 94, n° 4. https://archive-ouverte.unige.ch/unige:102866

65 hits

26 downloads

Update

Deposited on : 2018-03-12

Export document
Format :
Citation style :