Observed biomass overlap (I_Obs; with confidence intervals (CIs) in terms of null models) in different fertilization gradients.

Notes: Statistical tests were performed against the null expectation that species abundances within each fertilization gradient were unrelated to leaf functional traits; all tests were one-tailed; Bold types indicate a significant difference based upon 95% CI; ns, Not significant; F0, F15, F30 and F60 represent (NH4)2HPO4 fertilizer applications of 0, 15, 30 and 60 g m-2 yr-1. Observed biomass overlap (IObs; with confidence intervals (CIs) in terms of null models) in different fertilization gradients.