A hole in the nematosphere: tardigrades and rotifers dominate the cryoconite hole environment, whereas nematodes are missing

0541984 - BC 2022 RIV GB eng J - Článek v odborném periodiku
Zawierucha, K. - Porazinska, D. L. - Ficetola, G. F. - Ambrosini, R. - Baccolo, G. - Buda, J. - Ceballos, J. L. - Devetter, Miloslav - Dial, R. - Franzetti, A. - Fuglewicz, U. - Gielly, L. - Łokas, E. - Janko, Karel - Novotná Jaroměřská, T. - Kościński, A. - Kozłowska, A. - Ono, M. - Parnikoza, I. - Pittino, F. - Poniecka, E. - Sommers, P. - Schmidt, S. K. - Shain, D. - Sikorska, S. - Uetake, J. - Takeuchi, N.
A hole in the nematosphere: tardigrades and rotifers dominate the cryoconite hole environment, whereas nematodes are missing.
Journal of Zoology. Roč. 313, č. 1 (2021), s. 18-36. ISSN 0952-8369. E-ISSN 1469-7998
Institucionální podpora: RVO:60077344 ; RVO:67985904
Klíčová slova: distribution * ecological selection * extremophiles * glaciers * Nematoda * psychrophiles * Rotifera * Tardigrada
Obor OECD: Biodiversity conservation; Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology (UZFG-Y)
Impakt faktor: 2.394, rok: 2021
Způsob publikování: Open access
https://air.unimi.it/retrieve/handle/2434/793600/1655811/Zawierucha%202020%20J%20Zool%20submitted%20manuscript.pdf

The worldwide distribution of microinvertebrates on glaciers, the coldest biome, is poorly known. Owing to their tolerance to hostile conditions, small size and dispersal abilities, nematodes, tardigrades and rotifers are considered cosmopolitan and together inhabit various ecosystems. In this study, we investigated their global distribution in cryoconite holes – a type of freshwater reservoir forming directly in the glacial ice that creates biodiversity hotspots on glaciers. We analysed cryoconite samples (using classical microscopic observations and environmental DNA metabarcoding) from 42 glaciers located around the world (the Arctic, Subarctic, Scandinavia, the Alps, the Caucasus, Siberia, Central Asia, Africa, South America and Antarctica), as well as using literature data. Samples from Antarctic, Karakoram and the Alps were analysed using next-generation sequencing (NGS) and classical observations under microscopes, while all other samples were analysed by microscope alone. Three general outcomes were found: (1) tardigrades and rotifers represented the most common invertebrates in cryoconite holes, (2) tardigrades and rotifers often coexisted together, with one or the other dominating, but the dominant taxon varied by region or by glacier, (3) nematodes – the most abundant, hyperdiverse and widespread metazoans on Earth, including in environments surrounding and seeding glacial surfaces – were consistently absent from cryoconite holes. Despite the general similarity of environmental conditions in cryoconite holes, the distribution of tardigrades and rotifers differed among glaciers, but not in any predictable way, suggesting that their distribution mostly depended on the random dispersal, extreme changes of supraglacial zone or competition. Although nematodes have been found in supraglacial habitats, cryoconite hole environments seem not to provide the necessary conditions for their growth and reproduction. Lack of physiological adaptations to permanently low temperatures (~0°C) and competition for different food resources in the cryoconite hole environment may explain the absence of nematodes in cryoconite holes.
Trvalý link: http://hdl.handle.net/11104/0324678