title: The effects of foundation species on community assembly: a global study on alpine cushion plant communities.
abstract: Foundation species can change plant community structure by modulating important ecological processes such as community assembly, yet this topic is poorly understood. In alpine systems, cushion plants commonly act as foundation species by ameliorating local conditions. Here, we analyze diversity patterns of species' assembly within cushions and in adjacent surrounding open substrates (83 sites across five continents) calculating floristic dissimilarity between replicate plots, and using linear models to analyze relationships between microhabitats and species diversity. Floristic dissimilarity did not change across biogeographic regions, but was consistently lower in the cushions than in the open microhabitat. Cushion plants appear to enable recruitment of many relatively stress-intolerant species that otherwise would not establish in these communities, yet the niche space constructed by cushion plants supports a more homogeneous composition of species than the niche space beyond the cushion's influence. As a result, cushion plants support higher α-diversity and a larger species pool, but harbor assemblies with lower β-diversity than open microhabitats. We conclude that habitats with and without dominant foundation species can strongly differ in the processes that drive species recruitment, and thus the relationship between local and regional species diversity.
authors.forename: Zaal
authors.initials: Z
authors.lastname: Kikvidze
authors.forename: Robin W
authors.initials: RW
authors.lastname: Brooker
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Butterfield
authors.forename: Ragan M
authors.initials: RM
authors.lastname: Callaway
authors.forename: Lohengrin A
authors.initials: LA
authors.lastname: Cavieres
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Cook
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Lortie
authors.forename: Richard
authors.initials: R
authors.lastname: Michalet
authors.forename: Francisco I
authors.initials: FI
authors.lastname: Pugnaire
authors.forename: Sa
authors.initials: S
authors.lastname: Xiao
authors.forename: Fabien
authors.initials: F
authors.lastname: Anthelme
authors.forename: Robert G
authors.initials: RG
authors.lastname: Björk
authors.forename: Brittany H
authors.initials: BH
authors.lastname: Cranston
authors.forename: Rosario G
authors.initials: RG
authors.lastname: Gavilan
authors.forename: Robert
authors.initials: R
authors.lastname: Kanka
authors.forename: Emanuele
authors.initials: E
authors.lastname: Lingua
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Maalouf
authors.forename: Jalil
authors.initials: J
authors.lastname: Noroozi
authors.forename: Rabindra
authors.initials: R
authors.lastname: Parajuli
authors.forename: Gareth K
authors.initials: GK
authors.lastname: Phoenix
authors.forename: Anya
authors.initials: A
authors.lastname: Reid
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Ridenour
authors.forename: Christian
authors.initials: C
authors.lastname: Rixen
authors.forename: Christian
authors.initials: C
authors.lastname: Schöb
mesh_terms: D044822:Biodiversity; D008954:Models, Biological; D010944:Plants / Q000145:classification*; D012987:Soil / Q000737:chemistry*; D014867:Water
chemical_list: D012987:Soil; D014867:Water