PT  - JOURNAL ARTICLE
AU  - Raven L. Bier
AU  - Máté Vass
AU  - Anna J. Székely
AU  - Silke Langenheder
TI  - Ecosystem size-induced environmental fluctuations affect the temporal dynamics of community assembly mechanisms
AID  - 10.1101/2022.01.10.475621
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.01.10.475621
4099  - http://biorxiv.org/content/early/2022/01/11/2022.01.10.475621.short
4100  - http://biorxiv.org/content/early/2022/01/11/2022.01.10.475621.full
AB  - Understanding processes that determine community membership and abundance is important for many fields from theoretical community ecology to conservation. However, spatial community studies are often conducted only at a single timepoint despite the known influence of temporal variability on community assembly processes. Here we used a spatiotemporal study to determine how environmental fluctuation differences induced by mesocosm volumes (larger volumes were more stable) influence assembly processes of aquatic bacterial metacommunities along a press disturbance gradient. By combining path analysis and network approaches, we found mesocosm size categories had distinct relative influences of assembly process and environmental factors that determined spatiotemporal bacterial community composition, including dispersal and species sorting by conductivity. These processes depended on, but were not affected proportionately by, mesocosm size. Low fluctuation, large mesocosms primarily developed through the interplay of species sorting that became more important over time and transient priority effects as evidenced by more time-delayed associations. High fluctuation, small mesocosms had regular disruptions to species sorting and greater importance of ecological drift and dispersal limitation indicated by lower richness and higher taxa replacement. Together, these results emphasize that environmental fluctuations influence ecosystems over time and its impacts are modified by biotic properties intrinsic to ecosystem size.Competing Interest StatementThe authors have declared no competing interest.