Our knowledge on how habitat fragmentation affects biodiversity of aquatic microorganisms is primarily based on empirical studies. However, for a more realistic understanding of the underlying mechanisms, experiments that simultaneously investigate multiple taxonomical groups are needed. Our aim was to provide experimental proof for the negative effect of connectivity loss on microbial biodiversity by fragmentation in a habitat network. In an outdoor setup, we simulated six metacommunities, each consisting of five mesocosms (artificial ponds). For four weeks, weekly dispersal (water exchange) was carried out within each metacommunity, then it was terminated in three metacommunities to simulate connectivity loss, while it continued in the three control metacommunities for another 12 weeks. Applying 16S and 18S gene amplicon sequencing, we assessed the potential effects of fragmentation on biodiversity patterns of aquatic prokaryotes and unicellular microeukaryotes. By the end of the experiment, fragmentation resulted in a significantly lower alpha and gamma richness, and evenness of microeukaryotes, however, the strength of the treatment effect varied among the two trophic groups of microeukaryotes (autotrophs and heterotrophs). Our results revealed that under homogeneous environmental conditions, fragmentation remarkably decreased microeukaryotic diversity, while prokaryotes were not affected.

Primary Presenter: Beáta Szabó, Centre for Ecological Research (schneiderbea@gmail.com)

Authors:

Beata Szabo, Institute of Aquatic Ecology, Centre for Ecological Research, National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research  ()

Mate Vaczy-Foldi, School of Biological and Behavioural Sciences Queen Mary University of London, United Kingdom  ()

Csaba Vad, Institute of Aquatic Ecology, Centre for Ecological Research, National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research  ()

Adam Fierpasz, Institute of Aquatic Ecology, Centre for Ecological Research, Doctoral School of Biology, Institute of Biology, ELTE Eotvos Lorand University  ()

Karoly Palffy, Institute of Aquatic Ecology, Centre for Ecological Research, National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research  ()

Peter Dobosy, Institute of Aquatic Ecology, Centre for Ecological Research  ()

Thu Huong Huynh Ngoc, Institute of Aquatic Ecology, Centre for Ecological Research, National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research, Doctoral School of Biology, Institute of Biology, ELTE Eotvos Lorand University  ()

Zsuzsanna Marton, Institute of Aquatic Ecology, Centre for Ecological Research National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research, Doctoral School of Environmental Sciences, ELTE Eotvos Lorand University  ()

Attila Szabo, Swedish University of Agricultural Sciences, Institute of Aquatic Ecology, Centre for Ecological Research  ()

Tamas Felfoldi, Institute of Aquatic Ecology, Centre for Ecological Research, ELTE Eotvos Lorand University  ()

Zsofia Horvath, Institute of Aquatic Ecology, Centre for Ecological Research, National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research, ELTE Eotvos Lorand University  ()