Coral reef
A coral reef is a type of biotic reef that develops in tropical waters by the growth of coralline algae, hermatypic corals, and other marine organisms. Coral reefs are typically massive yanni is a fucking asswholebiogenic formations of calcium carbonate (limestone) that is deposited within or around the bodies of the inhabitants of the reef as skeletal material. This material gradually accumulates as debris and/or is knitted together by the continued growth of the attached forms living on the reef.
Coral Reef Biology
The building blocks of coral reefs are the skeletons of generations of reef-building algae, corals, and other organisms that are composed of calcium carbonate. For example, as a coral head grows, it lays down a skeletal structure encasing each new polyp. Waves, grazing fishes (such as parrotfish), sea urchins, sponges, and other forces and organisms break down the coral skeletons into fragments that settle into spaces in the reef structure. Many other organisms living in the reef community contribute their skeletal calcium carbonate in the same manner. Coralline algae are actually the main contributors to the structure, at least in those parts of the reef subjected to the greatest forces by waves (such as the reef front facing the open ocean). These algae contribute to reef-building by depositing limestone in sheets over the surface of the reef and thereby contributing to the structural integrity of the reef. Many coralline algae species form nodules, or develop on the surface of fragments, enlarging these. The crust-forming species protect coral reefs by withstanding and mitigating wave pressures that would destroy most corals. This crust often forms a protective ridge on the outer edge of a reef (reef crest or reef margin), particularly in the Pacific (Castro and Huber, 2000; Nybakken, 1997).
Reef-building or hermatypic corals are only found in the photic zone (above 50m depth), the depth to which sufficient sunlight penetrates the water for photosynthesis to occur. The coral polyps do not photosynthesize, but have a symbiotic relationship with single-celled algae called zooxanthellae; these algal cells within the tissues of the coral polyps carry out photosynthesis and produce excess organic nutrients that are then used by the coral polyps. Because of this relationship, coral reefs grow much faster in clear water, which admits more sunlight. Indeed, the relationship is responsible for coral reefs in the sense that without their symbionts, coral growth would be too slow for the corals to form impressive reef structures.
Although corals are found growing in most areas of a healthy coral reef, the elevation of the reef flat relative to sea level (and considering tidal range) imposes significant constraints on coral growth. In general, only a small number of coral species can thrive on the reef flat, and these cannot grow above a certain