title: Cross-scale analysis of the region effect on vascular plant species diversity in southern and northern European mountain ranges.
abstract: BACKGROUND
  The divergent glacial histories of southern and northern Europe affect present-day species diversity at coarse-grained scales in these two regions, but do these effects also penetrate to the more fine-grained scales of local communities?
  
  
  RESULTS
  We carried out a cross-scale analysis to address this question for vascular plants in two mountain regions, the Alps in southern Europe and the Scandes in northern Europe, using environmentally paired vegetation plots in the two regions (n = 403 in each region) to quantify four diversity components: (i) total number of species occurring in a region (total γ-diversity), (ii) number of species that could occur in a target plot after environmental filtering (habitat-specific γ-diversity), (iii) pair-wise species compositional turnover between plots (plot-to-plot β-diversity) and (iv) number of species present per plot (plot α-diversity). We found strong region effects on total γ-diversity, habitat-specific γ-diversity and plot-to-plot β-diversity, with a greater diversity in the Alps even towards distances smaller than 50 m between plots. In contrast, there was a slightly greater plot α-diversity in the Scandes, but with a tendency towards contrasting region effects on high and low soil-acidity plots.
  
  
  CONCLUSIONS
  We conclude that there are strong regional differences between coarse-grained (landscape- to regional-scale) diversity components of the flora in the Alps and the Scandes mountain ranges, but that these differences do not necessarily penetrate to the finest-grained (plot-scale) diversity component, at least not on acidic soils. Our findings are consistent with the contrasting regional Quaternary histories, but we also consider alternative explanatory models. Notably, ecological sorting and habitat connectivity may play a role in the unexpected limited or reversed region effect on plot α-diversity, and may also affect the larger-scale diversity components. For instance, plot connectivity and/or selection for high dispersal ability may increase plot α-diversity and compensate for low total γ-diversity.
authors.affiliation: Ecoinformatics and Biodiversity Group, Department of Biological Sciences, Aarhus University, Aarhus, Denmark. lenoir.john@gmail.com
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lenoir
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Gégout
authors.forename: Antoine
authors.initials: A
authors.lastname: Guisan
authors.forename: Pascal
authors.initials: P
authors.lastname: Vittoz
authors.forename: Thomas
authors.initials: T
authors.lastname: Wohlgemuth
authors.forename: Niklaus E
authors.initials: NE
authors.lastname: Zimmermann
authors.forename: Stefan
authors.initials: S
authors.lastname: Dullinger
authors.forename: Harald
authors.initials: H
authors.lastname: Pauli
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Willner
authors.forename: John-Arvid
authors.initials: JA
authors.lastname: Grytnes
authors.forename: Risto
authors.initials: R
authors.lastname: Virtanen
authors.forename: Jens-Christian
authors.initials: JC
authors.lastname: Svenning
mesh_terms: D044822:Biodiversity; D004463:Ecology; D017753:Ecosystem; D004777:Environment; D005060:Europe; D014644:Genetic Variation; D005843:Geography; D015233:Models, Statistical; D010802:Phylogeny; D006109:Poaceae; D012987:Soil; D013045:Species Specificity; D014197:Trees
chemical_list: D012987:Soil