Genetic and morphologic determination of diatom community composition in surface sediments from glacial and thermokarst
- PDF / 1,473,716 Bytes
- 18 Pages / 547.087 x 737.008 pts Page_size
- 8 Downloads / 178 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL PAPER
Genetic and morphologic determination of diatom community composition in surface sediments from glacial and thermokarst lakes in the Siberian Arctic S. Huang . U. Herzschuh . L. A. Pestryakova . H. H. Zimmermann . P. Davydova . B. K. Biskaborn . I. Shevtsova . K. R. Stoof-Leichsenring
Received: 1 October 2019 / Accepted: 19 May 2020 Ó The Author(s) 2020
Abstract Lakes cover large parts of the climatically sensitive Arctic landscape and respond rapidly to environmental change. Arctic lakes have different origins and include the predominant thermokarst lakes, which are small, young and highly dynamic, as well as large, old and stable glacial lakes. Freshwater diatoms dominate the primary producer community in these lakes and can be used to detect biotic responses to climate and environmental change. We used specific diatom metabarcoding on sedimentary DNA, combined with next-generation sequencing and diatom morphology, to assess diatom diversity in five glacial and 15 thermokarst lakes within the easternmost expanse of the Siberian treeline ecotone in Chukotka, Russia. We obtained 163 verified diatom Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10933-020-00133-1) contains supplementary material, which is available to authorized users. S. Huang U. Herzschuh H. H. Zimmermann B. K. Biskaborn I. Shevtsova K. R. Stoof-Leichsenring (&) Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Polar Terrestrial Environmental Systems, Telegrafenberg A45.2, 14473 Potsdam, Germany e-mail: [email protected]
sequence types and identified 176 diatom species morphologically. Although there were large differences in taxonomic assignment using the two approaches, they showed similar high abundances and diversity of Fragilariceae and Aulacoseiraceae. In particular, the genetic approach detected hidden within-lake variations of fragilarioids in glacial lakes and dominance of centric Aulacoseira species, whereas Lindavia ocellata was predominant using morphology. In thermokarst lakes, sequence types and valve counts also detected high diversity of Fragilariaceae, which followed the vegetation gradient along the treeline. Ordination analyses of the genetic data from glacial and thermokarst lakes suggest that concentrations of sulfate (SO42-), an indicator of the activity of sulfate-reducing microbes under anoxic conditions, and bicarbonate (HCO3-), which relates to surrounding vegetation, have a significant influence on diatom community composition. For thermokarst U. Herzschuh Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany L. A. Pestryakova P. Davydova Department of Geography and Biology, North-Eastern Federal University of Yakutsk, Belinskogo 58, Yakutsk, Russia 67700
U. Herzschuh Institute of Environmental Sciences and Geography, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
123
J
Data Loading...
