Table 1. Concentrations of phenolic substances in Cymodocea nodosa shoots collected at various distances from the natural CO2 vent site from the Island of Vulcano, Italy in May 2011.
| Conditions | Seawater carbonate chemistry | ||
| Distance from seep | 380m | 300m | 260m |
| Salinity | 37.16±0.07 | 37.12±0.06 | 37.05±0.1 |
| pH (units) | 8.11±0.01 | 7.84±0.04 | 7.32±0.05 |
| pCO2 (µtm) | 422±43 | 976±269.5 | 4009±1442.7 |
| TA (µmol kg-1) | 2549.6±29.6 | 2555.9±28.9 | 2592.5±48.3 |
Values are means +/− SE.
Average (±SE) temperature, salinity and pH were collected on different visits from Sept 2009 to May 2011 (n = 60). Total Alkalinity (TA) was calculated from water samples collected at each site on April and November 2010 (n = 4). Statistical analyses: 1, one-factor ANOVA with Holm-Sidak multiple comparisons; 2, Kruskal-Wallis One Way Analysis of Variance on Ranks with Tukey or Dunns multiple comparisons; 3, Two-factor ANOVA on ranks with Holm-Sidak multiple comparisons. Letters indicate results of pairwise comparisons test P<0.05. †a combined analysis indicated significant variation in the overall concentrations of the various compounds (factor: compound type; P<0.001) but there was no significant difference in how the compound types responded to changes in pH (interaction term; P = 0.900).