Loss of testate amoeba functional diversity with increasing frost intensity across a continental gradient reduces microbial activity in peatlands

Jassey, Vincent E. J. and Lamentowicz, Mariusz and Bragazza, Luca and Hofsommer, Maaike L. and Mills, Robert Thomas Edmund and Buttler, Alexandre and Signarbieux, Constant and Robroek, Bjorn J. M. (2016) Loss of testate amoeba functional diversity with increasing frost intensity across a continental gradient reduces microbial activity in peatlands. European Journal of Protistology, 55 (Part B). pp. 190-202. ISSN 0932-4739

[img]
Preview
PDF (1-s2.0-S0932473916300268-main)
1_s2.0_S0932473916300268_main.pdf - Accepted Version
Available under License Creative Commons Attribution-NonCommercial-NoDerivs.

Download (9MB)

Abstract

Soil microbial communities significantly contribute to global fluxes of nutrients and carbon. Their response to climate change, including winter warming, is expected to modify these processes through direct effects on microbial functions through osmotic stress, and changing temperature regimes. Using four European peatlands reflecting different frequencies of frost events, we show that peatland testate amoeba communities diverge among sites with different winter climates, and that this is reflected through contrasting functions. We found that exposure to harder soil frost promoted species β-diversity (species turnover) thus shifting the community composition of testate amoebae. In particular, we found that harder soil frost, and lower water-soluble phenolic compounds, induced functional turnover through the decrease of large species (-68%, > 80 μm) and the increase of small-bodied mixotrophic species (i.e. Archerella flavum; +79%). These results suggest that increased exposure to soil frost could be highly limiting for large species while smaller species are more resistant. Furthermore, we found that β-glucosidase enzymatic activity, in addition to soil temperature, strongly depended (R2 = 0.95, ANOVA) of the functional diversity of testate amoebae. Changing winter conditions can therefore strongly impact peatland decomposition process, though it remains unclear if these changes are carried–over to the growing season.

Item Type:
Journal Article
Journal or Publication Title:
European Journal of Protistology
Additional Information:
This is the author’s version of a work that was accepted for publication in European of Protistology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in European of Protistology, 55, Part B, 2016 DOI: 10.1016/j.ejop.2016.04.007
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/2400/2404
Subjects:
ID Code:
79355
Deposited By:
Deposited On:
05 May 2016 15:48
Refereed?:
Yes
Published?:
Published
Last Modified:
08 Apr 2020 03:16