title: Spatial scaling of microbial eukaryote diversity.
abstract: Patterns in the spatial distribution of organisms provide important information about mechanisms that regulate the diversity of life and the complexity of ecosystems. Although microorganisms may comprise much of the Earth's biodiversity and have critical roles in biogeochemistry and ecosystem functioning, little is known about their spatial diversification. Here we present quantitative estimates of microbial community turnover at local and regional scales using the largest spatially explicit microbial diversity data set available (> 10(6) sample pairs). Turnover rates were small across large geographical distances, of similar magnitude when measured within distinct habitats, and did not increase going from one vegetation type to another. The taxa-area relationship of these terrestrial microbial eukaryotes was relatively flat (slope z = 0.074) and consistent with those reported in aquatic habitats. This suggests that despite high local diversity, microorganisms may have only moderate regional diversity. We show how turnover patterns can be used to project taxa-area relationships up to whole continents. Taxa dissimilarities across continents and between them would strengthen these projections. Such data do not yet exist, but would be feasible to collect.
authors.affiliation: Key Centre for Biodiversity and Bioresources, Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia. jgreen@ucmerced.edu
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Green
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Holmes
authors.forename: Mark
authors.initials: M
authors.lastname: Westoby
authors.forename: Ian
authors.initials: I
authors.lastname: Oliver
authors.forename: David
authors.initials: D
authors.lastname: Briscoe
authors.forename: Mark
authors.initials: M
authors.lastname: Dangerfield
authors.forename: Michael
authors.initials: M
authors.lastname: Gillings
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Beattie
mesh_terms: D001203:Ascomycota / Q000145:classification / Q000235:genetics / Q000502:physiology*; D044822:Biodiversity; D017753:Ecosystem; D005057:Eukaryotic Cells / Q000145:classification / Q000502:physiology; D009517:New South Wales; D012988:Soil Microbiology