In mud flats there is not much zonation seen since there is little or no slope iv. Eel grass and turtle grass as well as fiddler crabs are common in this zone. Detritus feeding , where plant material is degraded by bacteria and fungi. An example of a detritus feeder is shrimp. Deposit feeding , where organisms engulf sediment and process it in their guts to extract organic matter.
Coral reefs have the greatest known diversity in the marine environment.
Hermatypic, or reef-building, corals require light and are limited to the upper 150 meters. Other organisms also contribute to the reef. The coral reef community contains the greatest known animal diversity in the ocean. Many benthic animals, especially from coral reefs, may produce special compounds that may have special medicinal applications. The food chain on a coral reef is not dependent on primary production.