title: A novel testate amoebae trait-based approach to infer environmental disturbance in Sphagnum peatlands.
abstract: Species' functional traits are closely related to ecosystem processes through evolutionary adaptation, and are thus directly connected to environmental changes. Species' traits are not commonly used in palaeoecology, even though they offer powerful advantages in understanding the impact of environmental disturbances in a mechanistic way over time. Here we show that functional traits of testate amoebae (TA), a common group of palaeoecological indicators, can serve as an early warning signal of ecosystem disturbance and help determine thresholds of ecosystem resilience to disturbances in peatlands. We analysed TA traits from two Sphagnum-dominated mires, which had experienced different kinds of disturbances in the past 2000 years - fire and peat extraction, respectively. We tested the effect of disturbances on the linkages between TA community structure, functional trait composition and functional diversity using structural equation modelling. We found that traits such as mixotrophy and small hidden apertures (plagiostomic apertures) are strongly connected with disturbance, suggesting that these two traits can be used as palaeoecological proxies of peatland disturbance. We show that TA functional traits may serve as a good proxy of past environmental changes, and further analysis of trait-ecosystem relationships could make them valuable indicators of the contemporary ecosystem state.
authors.affiliation: Laboratory of Wetland Ecology and Monitoring, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.|Department of Biogeography and Palaeoecology, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.|Institute of Plant Sciences and Oeschger Centre for Climate Change Research, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Marcisz
authors.affiliation: Institute of Plant Sciences and Oeschger Centre for Climate Change Research, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland.
authors.forename: Daniele
authors.initials: D
authors.lastname: Colombaroli
authors.affiliation: Ecole Polytechnique Federale de Lausanne, School of Architecture, Civil and Environmental Engineering, Ecological Systems Laboratory, Lausanne CH-1015, Switzerland.|WSL - Swiss Federal Institute for Forest, Snow and Landscape Research, Site Lausanne, Station 2, Lausanne CH-1015, Switzerland.
authors.forename: Vincent E J
authors.initials: VE
authors.lastname: Jassey
authors.affiliation: Institute of Plant Sciences and Oeschger Centre for Climate Change Research, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland.
authors.forename: Willy
authors.initials: W
authors.lastname: Tinner
authors.affiliation: Department of Biogeography and Palaeoecology, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Kołaczek
authors.affiliation: Department of Biogeography and Palaeoecology, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Gałka
authors.affiliation: Laboratory of Wetland Ecology and Monitoring, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.|Department of Biogeography and Palaeoecology, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Karpińska-Kołaczek
authors.affiliation: Department of Environmental Resources and Geohazards, Institute of Geography and Spatial Organisation, Polish Academy of Sciences, Twarda 51/55, 00-818 Warszawa, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Słowiński
authors.affiliation: Laboratory of Wetland Ecology and Monitoring, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.|Department of Biogeography and Palaeoecology, Adam Mickiewicz University, Krygowskiego 10, 61-680 Poznań, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Lamentowicz