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THE CORAL REEFS. BENEFITS FUNCTIONS THREATS SOLUTIONS. WHAT ARE CORALS?. CORAL IS AN INVERTEBRATE There are two groups of corals Hermatypes- hard corals Ahermatypes- soft corals. How are the reefs formed?.
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THE CORAL REEFS BENEFITS FUNCTIONS THREATS SOLUTIONS
WHAT ARE CORALS? • CORAL IS AN INVERTEBRATE • There are two groups of corals • Hermatypes- hard corals • Ahermatypes- soft corals
How are the reefs formed? • The term coral is used to describe the skeletal remains of these animals, particularly those of the hard corals which form the limestone base that becomes the foundations of the reefs.
THE GREAT BARRIER REEF DID YOU KNOW? The great Barrier Reef is the largest structure built by living organisms on earth and is the only living structure visible from outer space.
THE CORAL BODY A Hollow sac-like structure that appears smaller than a pencil eraser • The body of a coral animal is called a polyp.
The Coral Body • Polyps of the hard corals extract calcium carbonate from the sea water and use it to build a hard external limestone skeleton beneath and around their base . • This skeleton secures the fragile polyp to a surface and serves as its protection.
Food Source • Zooxanthellae • Planktons • Phytoplanktons • Zooplanktons • 60 % of the planktons on the reefs are eaten by the coral polyps. • Most corals feed only at nights. • Some coral are herbivores and some are carnivores
Sexually Asexually • Coral polyps reproduce both sexually and asexually • Sexual reproduction occurs when the corals spawn. • They release eggs and Sperms into the water. • The sperm then fertilizes the eggs forming a new creature called a planula. • Asexual reproduction occurs by budding. The parent polyp clones itself by dividing to from a new polyp which remains attached to the parent poly tissue. • A coral colony then develops by the constant adding of the new buds. Reproduction and Growth
BENEFITS They benefit both man and the environment • They are living organisms. • They are beautiful and enrich the life of the ocean. • They provide food and shelter to thousands of species of plants and animals. • They exchange energy and nutrients with other marine ecosystem.
Benefits to the environment Picture to the right shows the island of Bermuda surrounded by coral reefs. • They break waves. • Protect the shorelines from erosion. • Help to keep beaches and coastal communities intact.
More Benefits • Supplies finfish and shellfish upon which the national • economy depends • They provide food • They provide jobs • They provide recreation and entertainment • Provide ornamentals-jobs and income for tropical fish • gathers • They support tourism- snorkel, diving, boating fishing. • Health- Recent discoveries for treatment for cancer, AIDS, infection, arthritis, asthma, herpes, and even broken bones
More Benefits • The calcium carbonate from the skeleton of the corals of coral animals is used to produce lime which is added to cement and mortar to help it set more quickly. • The sand on the beach also benefit from coral reefs as it is formed by the breakdown of dead corals and algae.
Threats • Corals are highly sensitive to environmental conditions • They grow best in shallow water • Water must be clear between 68 degrees Fahrenheit and 84 degrees Fahrenheit. • The need normal oceanic salinity • They are being threatened globally by natural and man-made disasters.
NATURAL HUMANS • Global warming and the greenhouse effects. • Coral bleaching • Sea level changes • Hurricanes • Cyclones • Abnormal weather patterns • Fluctuations in seawater temperatures • Human impact is catastrophic • Over harvesting of fish • Use of cyanide and dynamite • Nutrients and pesticides draining into the reefs from agriculture • Boat anchors carelessly being dropped unto the reefs • Deposits of raw sewage Threats
NATURAL HUMANS • Heavy rains that dilute salinity • Extreme low tides • Diseases • Predator population explosion, e.g. Crown- of thorns- sea stars. • Tourists and locals stepping on the corals • Coral mining for construction materials • Sedimentation from deforestation • Road construction • Oil pollution from shipping Threats
Solutions • Education and Action • Reef preservation • What You can do: • Learn about reef preservation • Volunteer to help protect your reefs • Be informed about policy making
Solutions • Avoid purchasing products from coral reefs or their inhabitants • Be a responsible Eco-tourist • Support reef conservations • Be responsible when you dive and snorkel • Be a responsible boater and fisherman