Popis: |
Enrichment of the hermatypic Red Sea coral Stylophora pistillata with dissolved inorganic nitrogen, inorganic nitrogen + phosphorus, and feeding on Artemia , all led to increases in areal pigmentation in comparison with control colonies. These increases, unlike photoadaptive ones, resulted from growth in cell numbers ranging from × 2.75 in the Artemia -fed to × 4.85 in the N + P-enriched corals. The treated corals absorbed 51-85% of incident light, whereas the controls absorbed only 33%. Areal photosynthesis increased with treatment, although to a lesser degree than absorptivity. This difference resulted in reduced photosynthetic efficiencies in the treated colonies. Photosynthetic rates, calculated on a percell basis, were inversely correlated with algal densities, indicating possible competition among the algae for CO 2 . |