Invasive plant distributions recapitulate patterns found in native plant assemblages in a heterogeneous landscape

Abstract

Diverse alien and native floras of the same region provide a good opportunity to test the influence of environmental variables in structuring of plant assemblages because both can be considered as a replicates of the assembly process under identical conditions but with different dispersal capabilities. We performed this test within 11 floristically diverse areas forming the strictly defined Valley of River Volga (SE Russia), for the first time treating native and non‐native floras as independent replicates of the assembly process. We used a popular biogeographical method, parsimony analysis of endemicity (PAE) to estimate both non‐random components and the relationships of plant assemblages. We compared patterns of relationships obtained among plant assemblages based on (1) over 1000 presumably native, and (2) over 250 presumably non‐native species of the same assemblage and found that the PAE cladograms based on (1) presumably native and (2) presumably non‐native species of the same assemblage were topologically identical. The obtained patterns of relationships among plant assemblages were almost fully congruent with the climatic variables. The assembly processes of native and alien assemblages occurred in strikingly similar ways and therefore are not random. Climate and soil, but not dispersal limitation explained better the relationships among plant assemblages.

Keywords

• community convergence
• habitat filtering
• invasive and native plants
• parsimony analysis of endemicity (PAE)
• structure of plant assemblages