Table 3.
Posthoc Tukey’s Honestly Signficant Difference (HSD) tests for algal growth following pCO2 treatments for the model in Table 2a with algal growth as the response variable and CCRA genera and pCO2 as predictor variables. Growth changes have been back transformed. (a) Growth differences by pCO2 (b) growth differences by CCRA genera.
| (a) | ||
|---|---|---|
| pCO2 Pairwise Comparison | Difference (mm) | p |
| Normal and High | 10.29 | 0.01 |
| High and Extreme | 4.41 | 0.65 |
| Normal and Extreme | 14.70 | 0.008 |
| (b) | ||
| Genera Pairwise Comparison | Difference (mm) | p |
| Leptophytum spp. and Lithothamnion spp. | 29.9 | <0.0001 |
| Leptophytum spp. and Peyssonnelia sp. | 39.43 | <0.0001 |
| Leptophytum spp. and Lithophyllum spp. | 39.9 | <0.0001 |
| Lithothamnion spp. and Lithophyllum spp. | 9.0 | <0.31 |
| Lithothamnion spp. and Peyssonnelia sp. | 9.5 | =0.26 |
| Lithophyllum spp. and Peyssonnelia sp. | 0.57 | =0.99 |