Tropical coral reefs

• Coral nutrition comes from the cilia, they two planktonic items which are then passed Down to the stomach where they are digested
• Symbiotic algae absorb sunlight to photosynthesise and provide food energy
• Respiration of polyps produces CO2 this is used in photosynthesis
• Reef building corals release a limestone base continuously, this build up the reef over time
• Tropical coral reefs require high light levels
• They require a constant warm temperature
• Salinity of the water must be controlled
• Ocean acidifaction is caused by increased carbon dioxide concentrations in the atmosphere
• Coral reefs support over 25% of marine species
• Coral reefs support fisheries by supporting the species that are exploited for food such as fish and crustaceans
• Tropical Coral reefs are important for medical discoveries, species living on the reefs may produce toxic chemical to protect themselves, these can be carefully controlled to be used in medicine
• They are important in climate change control: coral reefs whilst growing act as carbon sinks
• They are important erosion protection: coral reefs absorb wave energy that could that could erode islands
• They are important for tourism as they are popular destination for recreational activities
• coral is used to make bone grafts
• Chemicals in sponges are used to treat HIV/AIDS
• Physical damage is a large threat, hard objects can kill polyps when pushed against the limestone beneath living cells
• Physical damage can be caused by boat anchors or divers
• Collection of souvenirs from coral reefs is a threat
• Trade of lots of species of coral reef is restricted by CITES in appendix II
• Sedimentation, turbid water can cover and kill corals
• Pollution is a threat, lots of pollutants can harm coral, pollutants such as runoff from agriculture or sewage effluent can stimulate growth of algae that covers corals
• Coral bleaching is caused by human actions such as increased water temperature or pollution
• Fishing is a threat, overfishing can reduce populations, affecting the coral
• Introduced species can be a threat, they can cause a decline in other species due to a new better adapted predator being introduced
• Coastal developments can be a threat, for instance by dredging an area
• Marine protected areas such as the great barrier reef and Belize can conserve this habitat
• Divers, swimmers can be taught not to touch corals to protect them
• Fishing can be controlled with quotas and maximum catch rates
• Sustainable development of ecotourism can help preserve the habitat
• Restrictions can be placed on damaging fishing methods to control fishing
• Sustainable exploitation can help conserve the habitat
• Reef creation has helped to conserve, artificial reefs have been created from concrete structures such as sinking objects made for other purposes
• Risk of pollution and therefore eutrophication from surface runoff of fertilisers or effluents
• increase in turbidity due to developmental schemes or destruction of mangroves can result in smothering the coral