In situ studies of metabolism in benthic reef communities

Abstract

1. Rates of net photosynthesis and respiration were determined in situ for Tridacna and coral species and their contained zooxanthellae at depths from 9 to 18 m. 2. Integrated daily total net photosynthesis to respiration ratios (P/R ratio) were calculated from these data to obtain the potential contribution of algal photosynthesis to the energy budget of the coral-algal symbiotic association. 3. The integrated daily P/R ratios varied between 0.79 and .89. Maximum ratios of photosynthesis to respiration rates ranged from 1.15 for Mussa arrgulosa to 2.91 for Manicina areolata. 4. Similar measurements were made on mixed benthic communities off southeastern Florida (USA) in a clean, unpolluted area and in an area influenced by the effluent of Biscayne Bay (USA). Very significant differences were found. © 1973 Biologischen Anstalt Helgoland.