Table 3. Linear mixed effect models for all nitrogen uptake and metabolism variables.
| Parameter | Source |
Halodule uninervis |
Thalassia hemprichii |
||||
|---|---|---|---|---|---|---|---|
| df | F | p | df | F | p | ||
| Nitrate uptake | pCO2 | 1 | 0.157 | 0.698 | 1 | 1.014 | 0.331 |
| Nitrate | 1 | 0.000 | 0.984 | 1 | 0.156 | 0.698 | |
| pCO2 ×Nitrate | 1 | 0.380 | 0.548 | 1 | 7.392 | 0.017 | |
| Nitrate reductase | pCO2 | 1 | 3.076 | 0.101 | 1 | 1.144 | 0.303 |
| Nitrate | 1 | 2.523 | 0.135 | 1 | 8.092 | 0.013 | |
| pCO2 ×Nitrate | 1 | 0.526 | 0.480 | 1 | 4.061 | 0.064 | |
| Glutamine synthetase | pCO2 | 1 | 0.142 | 0.712 | 1 | 0.089 | 0.769 |
| Nitrate | 1 | 0.376 | 0.550 | 1 | 0.289 | 0.600 | |
| pCO2 ×Nitrate | 1 | 3.443 | 0.085 | 1 | 0.466 | 0.506 | |
| Carbon content | pCO2 | 1 | 1.420 | 0.253 | 1 | 0.928 | 0.352 |
| Nitrate | 1 | 1.390 | 0.259 | 1 | 0.094 | 0.764 | |
| pCO2 ×Nitrate | 1 | 0.330 | 0.576 | 1 | 0.094 | 0.764 | |
| Nitrogen content | pCO2 | 1 | 0.310 | 0.584 | 1 | 2.180 | 0.162 |
| Nitrate | 1 | 1.350 | 0.266 | 1 | 4.363 | 0.056 | |
| pCO2 ×Nitrate | 1 | 0.510 | 0.487 | 1 | 3.113 | 0.099 | |
| C:N ratio | pCO2 | 1 | 1.571 | 0.231 | 1 | 1.436 | 0.251 |
| Nitrate | 1 | 3.227 | 0.094 | 1 | 4.846 | 0.045 | |
| pCO2 ×Nitrate | 1 | 0.282 | 0.604 | 1 | 3.258 | 0.093 | |
Variables were analysed with pCO2 as a continuous predictor and nitrate as a categorical factor. Individual aquaria were included as replicates (N = 3), with two sub-replicate pots nested within aquaria. P-values < 0.05 are in bold.