Calcification Rate

Calcification rate is the rate at which marine organisms deposit calcium carbonate to build skeletons, shells, and tests, expressed per unit area or biomass per unit time. In scleractinian corals it sets reef accretion against bioerosion and dissolution; in coccolithophores and foraminifera it governs the biological carbon and carbonate pumps. The rate depends on the aragonite or calcite saturation state, temperature, light, and the symbiosis with zooxanthellae that supplies photosynthate. As ocean acidification lowers carbonate-ion concentration and omega-aragonite, calcification slows: many reef corals show measurable declines as omega-aragonite falls toward 3, shifting reefs from net growth to net erosion.