Effect sizes (η²) for the effects of nutrient additions, light, grazing and time of sampling on periphyton biomass (chlorophyll <i>a</i> and AFDW), inorganic carbon uptake (Δ¹³C, biomass-specific ¹³C uptake (Δ¹³C/Chl <i>a</i> and Δ¹³C/AFDW), nu

All data are from the laboratory experiment and analyzed by repeated measures ANOVA. Significant effects are in boldface and denoted by *p<0.05, **p<0.01, ***p<0.001; for marginally significant effects, p values are given. The 3rd order interactions are not presented as none were significant. Effect sizes (η2) for the effects of nutrient additions, light, grazing and time of sampling on periphyton biomass (chlorophyll a and AFDW), inorganic carbon uptake (Δ13C, biomass-specific 13C uptake (Δ13C/Chl a and Δ13C/AFDW), nutrient content (C, N, and P) and nutrient ratios (N:P, C:P, and C:N).