N₂ fixation and photosynthesis rates in <i>Stylophora pistillata</i>.

<p>N₂ fixation expressed as ethylene production or amount of nitrogen fixed (A), gross photosynthesis expressed as <i>P</i>_g or <i>P</i>_c (B) and the contribution of fixed nitrogen to the photo-metabolic nitrogen demand (C) in <i>Stylophora pistillata</i> corals. All rates were quantified in corals collected from three different depths (5, 10 and 20 m) during winter and summer (n = 7–8; mean ± SE). Different lettering (a-c) indicates significant differences between depths and seasons based on two-factor permutational ANOVAs with pairwise and Bonferroni corrected Monte Carlo tests (significance level, <i>p</i> < 0.05).