title: Patterns of bacterial biodiversity in the glacial meltwater streams of the McMurdo Dry Valleys, Antarctica.
abstract: Microbial consortia dominate glacial meltwater streams from polar regions, including the McMurdo Dry Valleys (MDV), where they thrive under physiologically stressful conditions. In this study, we examined microbial mat types and sediments found in 12 hydrologically diverse streams to describe the community diversity and composition within and across sites. Sequencing of the 16S rRNA gene from 129 samples revealed ∼24 000 operational taxonomic units (<97% DNA similarity), making streams the most biodiverse habitat in the MDV. Principal coordinate analyses revealed significant but weak clustering by mat type across all streams (ANOSIM R-statistic = 0.28) but stronger clustering within streams (ANOSIM R-statistic from 0.28 to 0.94). Significant relationships (P < 0.05) were found between bacterial diversity and mat ash-free dry mass, suggesting that diversity is related to the hydrologic regimes of the various streams, which are predictive of mat biomass. However, correlations between stream chemistry and community members were weak, possibly reflecting the importance of internal processes and hydrologic conditions. Collectively, these results suggest that localized conditions dictate bacterial community composition of the same mat types and sediments from different streams, and while MDV streams are hotspots of biodiversity in an otherwise depauperate landscape, controls on community structure are complex and site specific.
authors: Department of Biology, University of New Mexico MSCO3 2020, 1 UNM, Albuquerque, NM 87131, USA.
authors: David J
authors: DJ
authors: Van Horn
authors: Department of Biology, University of New Mexico MSCO3 2020, 1 UNM, Albuquerque, NM 87131, USA.
authors: Caitlin R
authors: CR
authors: Wolf
authors: Department of Biology, University of New Mexico MSCO3 2020, 1 UNM, Albuquerque, NM 87131, USA.
authors: Daniel R
authors: DR
authors: Colman
authors: Department of Biology, University of New Mexico MSCO3 2020, 1 UNM, Albuquerque, NM 87131, USA.
authors: Xiaoben
authors: X
authors: Jiang
authors: Faculty of Science, Department of Ecology, Charles University in Prague, Viničná 7, 12844 Prague 2, Prague, Czech Republic.
authors: Tyler J
authors: TJ
authors: Kohler
authors: Institute of Arctic and Alpine Research, University of Colorado, 1560 30th Street, Boulder, CO 80303, USA.
authors: Diane M
authors: DM
authors: McKnight
authors: National Ecological Observatory Network, 1685 38th Street, Boulder, CO, 80301.
authors: Lee F
authors: LF
authors: Stanish
authors: Department of Biology, University of New Mexico MSCO3 2020, 1 UNM, Albuquerque, NM 87131, USA.
authors: Terrill
authors: T
authors: Yazzie
authors: Department of Biology, University of New Mexico MSCO3 2020, 1 UNM, Albuquerque, NM 87131, USA cvesbach@unm.edu.
authors: Cristina D
authors: CD
authors: Takacs-Vesbach
mesh_terms: D000864:Antarctic Regions; D001419:Bacteria / Q000145:classification* / Q000235:genetics; D044822:Biodiversity; D004269:DNA, Bacterial / Q000235:genetics; D017753:Ecosystem; D059013:Microbial Consortia; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D045483:Rivers / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: 16S rRNA gene; community structure; cyanobacteria; diversity; microbial mats; polar region