Long-term dynamics in microbial eukaryotes communities: a palaeolimnological view based on sedimentary DNA

• Published in: Molecular Ecology
• Main Authors: Capo, Éric, Debroas, Didier, Arnaud, Fabien, Guillemot, Typhaine, Bichet, Vincent, Millet, Laurent, Gauthier, Emilie, Massa, Charly, Develle, Anne-Lise, Pignol, Cécile, Lezjerowicz, Franck, Domaizon, Isabelle
• Other Authors: Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL), Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry ), Laboratoire Microorganismes : Génome et Environnement (LMGE), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université d'Auvergne - Clermont-Ferrand I (UdA)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), Swiss Federal Insitute of Aquatic Science and Technology Dübendorf (EAWAG), Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté COMUE (UBFC)-Université Bourgogne Franche-Comté COMUE (UBFC), Université de Genève = University of Geneva (UNIGE), Region Rhone-Alpes; EC2CO INSU program (France); ANR program (France) ANR-10-CEPL-0008
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: climate change; eDNA; lake; protists; eutrophication; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; [SDE]Environmental Sciences; Greenland; Igaliku
• Online Access: https://hal.science/hal-01568922; https://doi.org/10.1111/mec.13893

International audience Assessing the extent to which changes in lacustrine biodiversity are affected by anthropogenic or climatic forces requires extensive palaeolimnological data. We used high-throughput sequencing to generate time-series data encompassing over 2200 years of microbial eukaryotes (protists and Fungi) diversity changes from the sedimentary DNA record of two lakes (Lake Bourget in French Alps and Lake Igaliku in Greenland). From 176 samples, we sequenced a large diversity of microbial eukaryotes, with a total 16 386 operational taxonomic units distributed within 50 phylogenetic groups. Thus, microbial groups, such as Chlorophyta, Dinophyceae, Haptophyceae and Ciliophora, that were not previously considered in lacustrine sediment record analyses appeared to be potential biological markers of trophic status changes. Our data suggest that shifts in relative abundance of extant species, including shifts between rare and abundant taxa, drive ecosystem responses to local and global environmental changes. Community structure shift events were concomitant with major climate variations (more particularly in Lake Igaliku). However, this study shows that the impacts of climatic fluctuations may be overpassed by the high-magnitude eutrophication impacts, as observed in the eutrophicated Lake Bourget. Overall, our data show that DNA preserved in sediment constitutes a precious archive of information on past biodiversity changes.