Summary of mixed-effects model analyses for dissimilarity (Bray-Curtis distances) based on species composition and functional trait composition: (A) between-community dissimilarity per colonization period × seed addition treatment, (B) within-community dissimilarity across colonization period × see

Models were fitted by stepwise inclusion of fixed effects. Listed are the results of likelihood ratio tests (L ratio) that were applied to assess model improvement and the statistical significance of the fixed effects (p values). Arrows indicate increase (↑) or decrease (↓) of the variables with species richness, functional group number, after seed addition, with increasing colonization period or with time; SR  =  initial species richness, FG  =  functional group number, ADD  =  seed addition in 2005, C  =  colonization period.