The clear and warm waters of the tropical South Pacific support the abundant growth of both hard (scleractinian) and soft corals. Scleractinian species are corals that secrete hard skeletons of calcium carbonate from seawater. Diverse types of hermatypic species are the colonial corals, sometimes called frame-builders, which are the ones responsible for the growth of fringing, patch and barrier reefs around volcanic and limestone islands, and the growth of atoll reefs overlying subsiding volcanic foundations. Other organisms that make up reef ecosystems are important sand producers. The biogenic sand contributes to reef, lagoon and beach sediments. These organisms include foremost foraminifera, calcareous and coralline algae, as well as shelled molluscs, echinoderms, calcareous worms and bacteria. Reef-dwelling parrot fish and other coral-eroding fish species are also prolific living producers of coral sand. As they feed on coral polyps, parrot fish excrete fine carbonate sand that falls into interstices in the reef structure and washes onto the reef flat.
KeywordsTropical Cyclone Reef Flat Solomon Island Storm Wave Coral Rubble
Unable to display preview. Download preview PDF.