Appendix C. Treatment effects on macroalgal species at times not presented in the original article.
TABLE C1. Statistical analyses of the density of the green alga Cladophora glomerata in July, August, and November. The deviance and degrees of freedom express the fitting of the data to the generalized linear model (see Statistical analyses). The summary statistics are presented in Fig. C1.
Early July |
Mid-August |
Early November |
|||||
Deviance / df |
54 / 36 |
58 / 36 |
60 / 35 |
||||
Source |
df |
χ2 |
P |
χ2 |
p |
χ2 |
P |
Depth |
1 |
5.48 |
<0.05 |
2.23 |
0.14 |
10.00 |
<0.001 |
Nutrient |
2 |
37.61 |
<0.0001 |
1.56 |
NS |
21.93 |
<0.0001 |
Herbivory |
2 |
6.28 |
<0.05 |
37.51 |
<0.0001 |
32.01 |
<0.0001 |
Depth × nutrient |
2 |
11.97 |
<0.01 |
2.79 |
NS |
3.33 |
NS |
Depth × herbivory |
2 |
2.36 |
NS |
0.14 |
NS |
2.38 |
NS |
Nutrient × herbivory |
4 |
25.10 |
<0.0001 |
4.08 |
NS |
11.66 |
<0.05 |
Nutrient × herbivory × depth |
4 |
2.86 |
NS |
1.52 |
NS |
16.50 |
<0.01 |
TABLE C2. Statistical analyses of the density of the filamentous brown algae (Pilayella littoralis and Ectocarpus siliculosus) in August, September, and November. The deviance and degrees of freedom express the fitting of the data to the generalized linear model (see Statistical analyses). The summary statistics are presented in Fig. C2.
Mid-August |
Mid September |
Early November |
|||||
Deviance / df |
28 / 36 |
24 / 36 |
35 / 35 |
||||
Source |
df |
χ2 |
P |
χ2 |
P |
χ2 |
P |
Depth |
1 |
2.95 |
0.09 |
0.77 |
NS |
2.97 |
0.09 |
Nutrient |
2 |
7.50 |
<0.051 |
3.66 |
NS |
0.15 |
NS |
Herbivory |
2 |
13.86 |
<0.01 |
2.10 |
NS |
6.82 |
<0.05 |
Depth × nutrient |
2 |
0.88 |
NS |
5.16 |
0.08 |
11.27 |
<0.01 |
Depth × herbivory |
2 |
2.69 |
NS |
0.83 |
NS |
2.66 |
NS |
Nutrient × herbivory |
4 |
10.96 |
<0.05 |
1.93 |
NS |
7.99 |
0.09 |
Nutrient × herbivory × depth |
4 |
0.95 |
NS |
5.60 |
NS |
9.76 |
<0.05 |
TABLE C3. Statistical analyses of the density of the green alga Enteromorpha sp. in July, August, and November. The deviance and degrees of freedom express the fitting of the data to the generalized linear model (see Statistical analyses). Some non-significant interactions are omitted from the analyses (see Statistical analyses). The summary statistics are presented in Fig. C3.
Early July |
Mid-August |
Early November |
|||||
Deviance / df |
51 / 48 |
38 / 44 |
49 / 43 |
||||
Source |
df |
χ2 |
P |
χ2 |
P |
χ2 |
P |
Depth |
1 |
0.12 |
NS |
6.34 |
<0.05 |
0.85 |
N.S: |
Nutrient |
2 |
37.88 |
<0.0001 |
27.67 |
<0.0001 |
27.15 |
<0.0001 |
Herbivory |
2 |
1.19 |
NS |
11.87 |
<0.001 |
13.74 |
<0.01 |
Depth × nutrient |
2 |
— |
— |
9.25 |
<0.001 |
6.43 |
<0.05 |
Depth × herbivory |
2 |
— |
— |
6.68 |
<0.05 |
4.36 |
NS |
Nutrient × herbivory |
4 |
— |
— |
— |
— |
— |
— |
Depth × nutrient × herbivory |
4 |
— |
— |
— |
— |
— |
— |
TABLE C4. Statistical analyses of the density of the red algae Ceramium tenuicorne in July, September, and November. The deviance and degrees of freedom express the fitting of the data to the generalized linear model (see Statistical analyses). The summary statistics are presented in Fig. C3.
Early July |
Mid-September |
Early November |
|||||
Deviance / df |
38 / 36 |
29 / 36 |
18 / 35 |
||||
Source |
df |
χ2 |
P |
χ2 |
P |
χ2 |
P |
Depth |
1 |
21.24 |
<0.0001 |
1.61 |
NS |
0.96 |
NS |
Nutrient |
2 |
15.81 |
<0.001 |
7.70 |
<0.05 |
11.20 |
<0.01 |
Herbivory |
2 |
0.79 |
NS |
0.74 |
NS |
0.47 |
NS |
Depth × nutrient |
2 |
3.06 |
NS |
7.96 |
<0.05 |
9.24 |
<0.01 |
Depth × herbivory |
2 |
2.32 |
NS |
5.37 |
0.07 |
7.41 |
<0.05 |
Nutrient × herbivory |
4 |
2.12 |
NS |
1.53 |
NS |
1.97 |
NS |
Depth × nutrient × herbivory |
4 |
7.54 |
0.11 |
2.74 |
NS |
4.35 |
NS |
FIG. C1. Density of the green alga Cladophora glomerata (mean ± SE) in shallow and deep water, in the three nutrient levels (ambient concentration = white, low enrichment = grey, and high enrichment = black), and in herbivory treatment cages (OC = open, herbivory, RC = roofed herbivory, and CC = closed, no herbivory). The values refer to least square means and SE’s of the model (see Statistical analyses). |
FIG. C2. Density of the filamentous brown algae (consisting of Polayella littoralis and Ectocarpus siliculosus) (mean ± SE) in shallow and deep water, in the three nutrient levels (ambient concentration = white, low enrichment = grey, and high enrichment = black), and in herbivory treatment cages (OC = open, herbivory, RC = roofed herbivory, and CC = closed, no herbivory). The values refer to least square means and SE’s of the model (see Statistical analyses). |
FIG. C3. Density of the green alga Enteromorpha sp. (mean ± SE) in shallow and deep water, in the three nutrient levels (ambient concentration = white, low enrichment = grey, and high enrichment = black), and in herbivory treatment cages (OC = open, herbivory, RC = roofed herbivory, and CC = closed, no herbivory). The values refer to least square means and SE’s of the model (see Statistical analyses). |
FIG. C4. Density of Ceramium tenuicorne (mean ± SE) in shallow and deep water, in the three nutrient levels (ambient concentration = white, low enrichment = grey, and high enrichment = black), and in herbivory treatment cages (OC = open, herbivory, RC = roofed herbivory, and CC = closed, no herbivory). The values refer to least square means and SE’s of the model (see Statistical analyses). |