Short-term responses of unicellular planktonic eukaryotes to increases in temperature and UVB radiation

BMC Microbiology

Research Article

Jean Francois Ghiglione¹  Didier Debroas²  Cécile Lepère²  Stephan Jacquet³  Isabelle Domaizon³  Amy Kirkham³  Helene Montanié⁴  Yvan Bettarel⁵  Marc Bouvy⁵  Emilie LeFloc’h⁵  Thierry Bouvier⁵  Francesca Vidussi⁵  Behzad Mostajir⁵  Corinne Bouvier⁵  Eric Fouilland⁵  Jean Pascal Torréton⁵ 

[1] CNRS, UMR 7621, LOMIC, Observatoire Océanologique, Avenue de Fontaulé, F-66651, Banyuls/mer, France;Clermont Université, Université Blaise Pascal, CNRS, UMR 6023, LMGE, BP 10448, F-63000, Avenue des Landais, Clermont Ferrand, France;INRA, UMR 42 CARRTEL, 75 avenue de Corzent, BP511, F-74200, Thonon-les-bains, France;LIttoral ENvironnement et Sociétés (LIENSs) - UMR 6250, Université de La Rochelle, Institut du Littoral et de l’Environnement (ILE), 2 rue Olympe de Gouges, 17 000, La Rochelle, France;Université Montpellier 2, UMR 5119 ECOSYM, CNRS, IRD, Ifremer, Université Montpellier 1, Place E Bataillon, cc 093, Montpellier cedex 5, 34095, France;

关键词: Small eukaryotes;    Molecular diversity;    Temperature;    UVB radiation;    Microcosms experiment;    Mediterranean lagoon;   

DOI  :  10.1186/1471-2180-12-202

 received in 2012-03-22, accepted in 2012-08-27,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundSmall size eukaryotes play a fundamental role in the functioning of coastal ecosystems, however, the way in which these micro-organisms respond to combined effects of water temperature, UVB radiations (UVBR) and nutrient availability is still poorly investigated.ResultsWe coupled molecular tools (18S rRNA gene sequencing and fingerprinting) with microscope-based identification and counting to experimentally investigate the short-term responses of small eukaryotes (<6 μm; from a coastal Mediterranean lagoon) to a warming treatment (+3°C) and UVB radiation increases (+20%) at two different nutrient levels. Interestingly, the increase in temperature resulted in higher pigmented eukaryotes abundances and in community structure changes clearly illustrated by molecular analyses. For most of the phylogenetic groups, some rearrangements occurred at the OTUs level even when their relative proportion (microscope counting) did not change significantly. Temperature explained almost 20% of the total variance of the small eukaryote community structure (while UVB explained only 8.4%). However, complex cumulative effects were detected. Some antagonistic or non additive effects were detected between temperature and nutrients, especially for Dinophyceae and Cryptophyceae.ConclusionsThis multifactorial experiment highlights the potential impacts, over short time scales, of changing environmental factors on the structure of various functional groups like small primary producers, parasites and saprotrophs which, in response, can modify energy flow in the planktonic food webs.

【 授权许可】

CC BY   
© Domaizon et al.; licensee BioMed Central Ltd. 2012