Origin Matters: Diversity Affects the Performance of Alien Invasive Species but Not of Native Species

Abstract

Online enhancement: appendix. Dryad data: http://dx.doi.org/10.5061/dryad.81nk5.abstract: At local scales, it has often been found that invasibility decreases with increasing resident plant diversity. However, whether resident community diversity similarly resists invasion by alien versus native species is seldom studied. We examined this issue by invading constructed native plant assemblages that varied in species and functional richness with invasive alien or native Asteraceae species. Assemblages were also invaded with spotted knapweed, Centaurea stoebe, a native European aster that has been previously used in diversity-invasibility experiments in North America. We also conducted a field survey to explore the generality of the patterns generated from our experimental study. Both experimental and observational work revealed that increasing diversity reduced the performance of alien but not native invaders. Centaurea stoebe invading its native community performed poorly regardless of resident diversity, whereas in a parallel, previously published study conducted in North America, C. stoebe easily invaded low-diversity but not highdiversity assemblages. Our results suggest that diversity is an attribute of resident communities that makes them more or less susceptible to invasion by novel invasive alien but not native plant species.

Species pools, community completeness and invasion: disentangling diversity effects on the establishment of native and alien species

“…Still, differences in interactions with the resident community increased biotic resistance to alien species (Knapp & Kühn ; Sun et al . ). Higher biotic resistance for alien species runs contrary to most hypotheses (Buckley & Catford ), yet it is not without precedent (Sun et al .…”

“…Higher biotic resistance for alien species runs contrary to most hypotheses (Buckley & Catford ), yet it is not without precedent (Sun et al . ). Importantly, establishment and the biotic effects on establishment were related to different aspects of the community and environment for native and alien species, suggesting important functional differences between these species groups despite close phylogenetic relationships.…”

“…), these aspects of their ecology can also differ (Buckley & Catford ), potentially altering diversity‐invasion relationships (Sun et al . ). Consequently, understanding the diversity‐invasion relationship may require separate consideration of native and alien species.…”

“…The relationship between completeness, species pools and invasion may also depend on the origin of the invading species. Although native and alien species can have similar establishment (Lemoine et al 2015) and competitive abilities (Dawson et al 2012), these aspects of their ecology can also differ (Buckley & Catford 2016), potentially altering diversityinvasion relationships (Sun et al 2015). Consequently, understanding the diversity-invasion relationship may require separate consideration of native and alien species.…”

Does the biogeographic origin of species matter? Ecological effects of native and non‐native species and the use of origin to guide management

“…Using multiple native and non‐native Asteraceae species, Sun et al . () demonstrated that invasibility declined with increasing recipient community species richness when the invader was non‐native but not when it was native.…”