Asymmetrical multivariate analyses on the structure of assemblages in different sites in all sampling times.

n = 4. The whole analyses is shown as well as the a priori contrast (i.e. the analyses where the distances to be compared were chosen a priori). ns = not significant; * = p<0.05; ** = p<0.01. Eff = Effluent; 600 m and 1400 m = sites 600 and 1400 m away from the effluent, respectively. Factor 1: Distance (Di), fixed, with 2 levels; Factor 2: Sites (Si), random, nested in Distance; Factor 3: Time (Ti), random, with 4 levels (except in comparisons with the Control sites, where there were only 2 levels). Data were squared-root transformed. +Because the analysis “effluent vs. controls” was only done for two times of sampling, the degrees of freedom of Time is 1, Di (Ti) and Lo(Di) X Ti are 3 and the residual is 42.