Original Research ARTICLE
Carbon pathways through the food web of a microbial mat from Byers Peninsula, Antarctica
- 1Department of Biology, Faculty of Science, Autonomous University of Madrid, Spain
- 2Department of Ecology, Faculty of Science, Autonomous University of Madrid, Spain
- 3Department of Mathematics, Faculty of Science, Autonomous University of Madrid, Spain
Microbial mats are complex communities that represent a large biomass fraction in non-marine Antarctic ecosystems. They confer structure to soils and constitute, by themselves, intricate micro-ecosystems, where a great variety of microorganisms and microfauna contributes to the ecosystem functions. Although in recent years Antarctic microbial mats have been thoroughly investigated, trophic relationships within the communities remain unresolved. We therefore conducted a study of the trophic relationships of a microbial mat from Byers Peninsula, Antarctica, using DNA analysis and stable isotopes as trophic tracers. Our results suggested, based on a Bayesian mixing model, that at least 4 trophic levels are present within this microecosystem: primary producers (cyanobacteria and diatoms), primary consumers (rotifers and tardigrades), secondary consumers (nematodes) and decomposers (fungi). Nematodes would play a key role as top consumers of the community, connecting the two carbon inputs described into the system, as omnivores at the secondary trophic level. In addition, carbon pathways from primary trophic level to consumers take place quickly during the first 24 hours after its incorporation in the primary producers, dispersing across all the trophic levels and reaching secondary consumers in less than 11 days. This suggests that, given the changing physical conditions and presumably short periods of activity, there is a fine temporal coupling among the organisms in the community, minimizing the redundancy in function performance among trophic levels.
Keywords: microbial mats, Antarctica, Cyanobacteria, Trophic web, carbon pathways, Stable isotopes, Prokaryotic community, Eukaryotic community
Received: 22 Sep 2018;
Accepted: 13 Mar 2019.
Edited by:Jesse G. Dillon, California State University, Long Beach, United States
Reviewed by:BRENDAN P. BURNS, University of New South Wales, Australia
Nicola Wannicke, Leibniz-Institut für Plasmaforschung und Technologie e.V. (INP), Germany
Copyright: © 2019 Almela, Velázquez, Rico, Justel and Quesada. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Antonio Quesada, Department of Biology, Faculty of Science, Autonomous University of Madrid, Madrid, Madrid, Spain, email@example.com