Bacterial diversity in Icelandic cold spring sources and in relation to the groundwater amphipod Crangonyx islandicus

• Published in: PLOS ONE
• Main Authors: Gudmundsdottir, Ragnhildur, Kreiling, Agnes-Katharina, Kristjánsson, Bjarni Kristófer, Marteinsson, Viggó, Palsson, Snaebjorn
• Other Authors: Líf- og umhverfisvísindadeild (HÍ), Faculty of Life and Environmental Sciences (UI), Fiskeldis- og fiskalíffræðideild (HH), Department of Aquaculture and Fish Biology (HUC), Matvæla- og næringarfræðideild (HÍ), Faculty of Food Science and Nutrition (UI), Verkfræði- og náttúruvísindasvið (HÍ), School of Engineering and Natural Sciences (UI), Heilbrigðisvísindasvið (HÍ), School of Health Sciences (UI), Háskóli Íslands, University of Iceland, Háskólinn á Hólum, Hólar University College
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2019
• Subjects: Bacteria; Iceland; Crangonyx islandicus; Marflær; Gerlar; Vistfræði
• Online Access: https://hdl.handle.net/20.500.11815/1904; https://doi.org/10.1371/journal.pone.0222527

Publisher's version (útgefin grein) Crangonyx islandicus is a groundwater amphipod endemic to Iceland, considered to have survived the Ice Ages in subglacial refugia. Currently the species is found in spring sources in lava fields along the tectonic plate boundary of the country. The discovery of a groundwater species in this inaccessible habitat indicates a hidden ecosystem possibly based on chemoautotrophic microorganisms as primary producers. To explore this spring ecosystem, we assessed its microbial diversity and analysed whether and how the diversity varied between the amphipods and the spring water, and if was dependent on environmental factors and geological settings. Isolated DNA from spring water and from amphipods was analysed using metabarcoding methods, targeting the 16S rRNA gene. Two genera of bacteria, Halomonas and Shewanella were dominating in the amphipod samples in terms of relative abundance, but not in the groundwater samples where Flavobacterium, Pseudomonas and Alkanindiges among others were dominating. The richness of the bacteria taxa in the microbial community of the groundwater spring sources was shaped by pH level and the beta diversity was shaped by geographic locations. This work was supported by the Icelandic Research Council [grant number: 130244-051 to SP and 141863-051 to BKK] and by the doctoral fund at the University of Iceland. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Peer Reviewed