PHOTOSYNTHESIS, RESPIRATION AND CALCIFICATION OF A ZOOXANTHELLATE SCLERACTINIAN CORAL UNDER SUBMERGED AND EXPOSED CONDITIONS

An experimental set-up was designed to investigate photosynthesis, res piration and calcification of zooxanthellate scleractinian corals unde r submerged and exposed conditions. The results of experiments to dete rmine the effect of exposure to air on the metabolism of Stylophora pi stillata (Esper, 1797) revealed that: (1) maximum gross photosynthesis (p(gmax)) is 3.6 times higher in water than in air; (2) an indicator of photoadaptation (I-k) does not reveal ally 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 (alpha) than aquatic P-I cu rves; (5) there is no calcification in air.