title: Advection shapes Southern Ocean microbial assemblages independent of distance and environment effects.
abstract: Although environmental selection and spatial separation have been shown to shape the distribution and abundance of marine microorganisms, the effects of advection (physical transport) have not been directly tested. Here we examine 25 samples covering all major water masses of the Southern Ocean to determine the effects of advection on microbial biogeography. Even when environmental factors and spatial separation are controlled for, there is a positive correlation between advection distance and taxonomic dissimilarity, indicating that an 'advection effect' has a role in shaping marine microbial community composition. This effect is likely due to the advection of cells increasing the probability that upstream microorganisms will colonize downstream sites. Our study shows that in addition to distance and environmental selection, advection shapes the composition of marine microbial communities.
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Wilkins
authors.forename: Erik
authors.initials: E
authors.lastname: van Sebille
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Rintoul
authors.forename: Federico M
authors.initials: FM
authors.lastname: Lauro
authors.forename: Ricardo
authors.initials: R
authors.lastname: Cavicchioli
mesh_terms: D059013:Microbial Consortia / Q000235:genetics; D009792:Oceans and Seas; D017422:Sequence Analysis, DNA; D014871:Water Microbiology; D014872:Water Movements