Appendix S4 Effects of the experimental treatments on the taxon richness of zooplankton, phytoplankton and bacterioplankton communities.
Zooplankton richness increased with dispersal intensity and was significantly higher in the low than in the high nutrient addition treatment (Table 1; Figure1.1). For the phytoplankton communities, we observed a significant nutrient x dispersal interaction effect: strong dispersal had a positive effect on species richness but only in the low nutrient addition treatment (Table
1; Figure1.2). For the bacterioplankton community, there was a tendency towards a significant interaction between the nutrient addition and dispersal treatments, but Tukey posthoc analysis gave no support for any pairwise difference among treatments (Table 1; Figure1.3).
Table 1. ANOVA results for the response of the taxon richness of zooplankton, phytoplankton and bacterioplankton communities to the experimental treatments
Zooplankton
LAKE ID
NUT d.f. SS
15 26.96
MS
1.8
F
1.05 p
0.458
1 108.38 108.38 85.75 < 0.001
DISP 2 60.44 30.22 27.28 < 0.001
NUT x DISP 2 0.063 0.032 0.048 0.953
Phytoplankton
LAKE ID
NUT
DISP d.f. SS
15 157.17
MS
10.48
F
1.92 p
0.277
1 108.38 108.38 18.27 < 0.001
2 113.31 56.66 6.69 0.00396
NUT x DISP 2 120.81 60.41 6.77 0.00376
Bacterioplankton d.f. SS
LAKE ID
NUT
15 175.57
MS
11.71
F
2.31 p
0.227
1 0.51 0.51 0.074 0.789
DISP 2 4.94 2.47 0.38 0.686
NUT x DISP 2 77.9 38.95 4.73 0.0164

c
1
6 HNUT
LNUT b b b
4 a a
2
0
12
10
8
6
18
16
14
12
10
8
6
NDISP LDISP HDISP b 2 a a
NDISP LDISP HDISP a a a a a a a a a
3
4
NDISP LDISP HDISP
Figure 1: Species richness in the zoo-, phyto-, and bacterioplankton communities for each treatment combination. Error bars denote twice the standard error. Characters indicate significant Tukey post hoc differences (p<0.05).