Also see Coral.
5. Coral Reefs Defined
Coral reefs are the most spectacular under-water structures. These are the marine habitats of thousands of marine species. They are of three types - Fringing Reefs, Barrier Reefs, and Atolls. The gradual cementing of the hard skeletons of tiny living organisms called coral polyps over thousands of years result in coral reef formations. These organisms have zooxanthellae in their tissues. Zooxanthellae is a type of algae that produces oxygen by photosynthesis and provide glucose, glycerol, and amino acids to the coral polyps. It also gives attractive colors to the coral polyps. The later in return provides protection to the algae by forming a hard limestone shell. This mutual relationship helps the coral polyps to produce protein, fat, carbohydrate and calcium carbonate. Thus, they gradually grow and form colonies to form a coral reef.
4. Notable Examples
The Great Barrier Reef in the Coral Sea near Australia and the New Caledonia Barrier Reef located near New Caledonia in the Pacific Ocean are the notable examples of Coral Reef across the world. Of these, the Great Barrier Reef is the largest one and is an approximate 2500 km in length.
3. Significance to Humans
Coral Reefs are of great significance to humans as these protect coastal settlements from tropical storms by dissipating the wave energy of the sea and minimizing the damage in the coastal areas. The chemicals obtained from coral reefs are also used to make various forms of drugs for curing life-threatening diseases like cancer. Coral reefs are important spawning grounds of a number of marine fish species. Coral reefs also promote tourism and are essential for the sustainability of the fishing industry as that offers employment to billions of people all over the world.
2. Habitat and Biodiversity
Coral reefs are present in the warm and clean waters of the tropical and sub-tropical oceans across the earth. These are in areas where the depth of water is less than 150-450 feet. Coral reefs have a biodiversity of even higher than that of a tropical forest. These are the homes of approximate 2 million marine species including fishes, turtles, sea horses, lobsters, crabs, shrimps, algae, sharks, urchins, sponges, clams, octopuses, monk seals, and much more. Scientists are still discovering marine species living on coral reefs.
1. Environmental Threats and Conservation
The rising temperature of seawater is a major environmental threat to coral reefs. As the temperature rises, the bleaching process sets in and eventually, corals starve to death. Ocean acidification also degrades the coral reefs. More carbon dioxide in the ocean water will reduce the ability of corals to build their limestone exteriors, by which they attach themselves to the substrate. Excessive fishing, shoreline development, and seawater pollution are some other threats to the same. United States has formed the United States Coral Reef Task Force and the NOAA Coral Reef Watch program for the conservation of coral reefs. In Australia, there is Great Barrier Reef Marine Park Authority, and in Japan, there is the Global Coral Reef Conservation Project for the restoration of beautiful coral reefs. Many small countries are also contributing to coral reef conservation by putting a restriction on fishing.