What are Coral Reefs? • Coral reefs are warm, clear, shallow ocean habitats that are rich in life. The reef's massive structure is formed from coral polyps, tiny animals that live in colonies; when coral polyps die, they leave behind a hard, stony, branching structure made of limestone.
Conditions for the growth of coral reefs • Sea temperature between 20c and 30c. • Shallow sea water less than 70 m deep • Clear slat water • Polyps thrive on the seaward side of the coral reefs where waves and currents bring an abundant supply of oxygen and food. • Extensive coral formations develop between latitudes of 30 degrees N and 30 degrees south, on the eastern side of land masses where there are warm currents.
Why should we care about coral reefs? • Coral reefs are important to our future. They are: • home and nursery for almost a million fish and other species, many that we rely on for food; • some of the earth's most diverse living ecosystems; • important protection for coastal communities from storms, wave damage and erosion; • full of new and undiscovered biomedical resources that we've only just begun to explore. • Reefs are a recreational resource for local people and for tourism.
Types of Coral Reefs • Fringing reefs- a narrow coral platform separated from the coast by a shallow lagoon. • Barrier reefs- a coral platform separated from the coast by a deep wide lagoon. • Atoll- a circular coral reef which encloses a lagoon.
Causes and Effects of Coral Reef Degradation • Pollution from sewage discharge Sewage pollution is one of the main causes of coral reef degradation. Sewage that is rich in nutrients foster the growth of excess algae and bacteria.
2) Industrial and Agricultural Run-off Toxic chemicals and organic waste from industrial and agricultural activities have become a serious coastal pollution problem. These chemicals are toxic to marine life and on the coral reefs. Organic fertilizers increase the growth of harmful algae.
3)Tourism-related Activity (Coastal Development -Clearing of land for construction of hotels, roads and artificial beaches. -Collection of specimens for souvenirs. -Berthing of boats: boats anchor on reefs to allow scuba diving and viewing. -Trampling by divers.
4)Inland Pollution and Erosion (siltation) from poor land-use Soil that is eroded from hillsides find its way to coastal waters and chokes corals. 5)Over-fishing The use of irregular-sized nets, poison and dynamiting cause harmful damage to coral reefs.
6)Hurricanes Strong waves associated with hurricanes and storms erode the most fragile section of the reef. 7)High water Temperatures High water temperatures ‘bleach’ corals (makes them white), eventually killing them.
Implications of Coral Reef Degradation Coral reefs protect the land from storm and tidal surges and provide a source of economic development and fish for consumption. If they are damaged then the implications could seriously affect sustainable development in the Caribbean. So it is important we protect them.
Classwork • Describe the value of coral reefs to Caribbean society and culture and explain TWO measures that can be implemented to minimize the dangers posed to coral reefs in the region. ( 20 marks) • “ Flooding is caused by a combination of natural and man- made factors.” Discuss the extent to which flooding is a major environmental hazard in the Caribbean. ( 20 marks)