Photosynthesis, respiration and calcification of a zooxanthellate scleractinian coral under submerged and exposed conditions

An experimental set-up was designed to investigate photosynthesis, respiration and calcification of zooxanthellate scleractinian corals under submerged and exposed conditions. The results of experiments to determine the effect of exposure to air on the metabolism of Stylophora pistillata (Esper, 1797) revealed that: (1) maximum gross photosynthesis ( p _{g max}) is 3.6 times higher in water than in air; (2) an indicator of photoadaptation (I _k ) does not reveal any difference between water and air; (3) the difference between submerged and aerial respiration is not statistically significant; (4) aerial photosynthesis–irradiance (P–I) curves display lower initial slopes (α) than aquatic P–I curves; (5) there is no calcification in air. Received: 7 February 1997 / Accepted: 4 March 1997