Table 2.
A summary of the generalized mixed models for the effects of plant-specific diversity (mono-, di- and tricultures) and the presence of mutualistic ants (two levels: presence or absence) on the abundance of the associated arthropod community at several trophic levels. The effect of the particular combination of pine species (three mono-, three di- and three tricultures) nested in each diversity treatment was included in the model. Ant treatments took four months. Final height was used as covariate. Significant p-values (p < 0.05) are indicated in bold.
| DFnum | DFden | F | p-value | F | p-value | F | p-value | |
|---|---|---|---|---|---|---|---|---|
| ant-tended aphids | aphid predators | non-aphid herbivores | ||||||
| ant | 1 | 3 | 172.32 | 0.001 | 19.80 | 0.021 | 1.58 | 0.298 |
| diversity | 2 | 47 | 25.96 | <0.001 | 2.17 | 0.126 | 0.48 | 0.623 |
| ant × diversity | 2 | 47 | 33.29 | <0.001 | 0.81 | 0.453 | 0.88 | 0.423 |
| combination | 6 | 47 | 1.73 | 0.135 | 1.44 | 0.219 | 1.41 | 0.230 |
| ant × combination | 6 | 47 | 1.49 | 0.201 | 0.90 | 0.504 | 0.57 | 0.749 |
| final height | 1 | 47 | 1.93 | 0.171 | 2.79 | 0.101 | 0.01 | 0.919 |
| ants | ant : aphid ratio | |||||||
| diversity | 2 | 23 | 19.13 | <0.001 | 5.46 | 0.011 | ||
| combination | 6 | 23 | 2.49 | 0.053 | 1.35 | 0.278 | ||
| final height | 1 | 23 | 1.27 | 0.272 | 0.01 | 0.933 | ||