CORAL REEFS

CORAL REEFS
Coral refers to a particular class of animal belonging to the group cnidaria of phylum Coelenterata. It is a softbodied radially symmetrical marine invertebrate which secretes a calcareous skeleton. A coral reef is formed by the cementing together of millions of these calcareous skeletons over a long period of time. The reefs are of three types-fringe, barrier and atoll. Coral reefs are shallow water tropical marine ecosystems marked by a high bio­mass production and a rich flora and faunal diversity.

Coral reefs alongwith associated communities cover about 6PO,000 sq km of the oceans (about 0.2 per cent of the total ocean area), but are mainly found between the Tropic of Cancer and the Tropic of Capricorn. The life forms in coral reefs and other marine ecosystems are much more varied than those in land habitats. The largest coral reef area is in Indonesia, followed by Australia and Philippines. India has about 50,000 sq km of coral reefs which is about 2 per cent of the world total.

Coral reefs provide carbon dioxide sinks and are sources of huge deposits of calcium carbonate. They pro­vide raw materials for medicinal drugs and formulations. Some of these chemicals have been used in treatment of HIV and cancer. Coral reef ecosystems are good fish breeding grounds. They are natural breakwaters protecting vulnerable beaches from wave action and floods. Coral reefs are of tourist interest as well. Coral is also used in jewellery.

The major reef formations in India are restricted to Gulf of Mannar, Gulf of Kutch, Andaman and Nicobar, and Lakshadweep Islands. Patchy coral growth is present at the inter-tidal areas of the central west coast. More than 200 coral species are known in the Indian reefs. In the Indian sub-continent, fringing reefs are found in the Gulf of Mannar and Palk Bay besides the Andaman and Nicobar Islands. Platform reefs are found along the Gulf of Kutch, and atolls are found in the Lakshadweep.

In costal areas coral reefs are being destroyed by pollutants, siltation from upstream erosion, use of dynamite and poison in fishing, mining for construction building and extraction for the cement industry. Scientists point out that elevated sea temperatures-possibly due to global warm­ing-cause coral 'bleaching' in which the coral's symbiotic algae,~ which give coral its colour, abandon the cmal. Without these algae the coral will eventually die. The
. destruction of coral reefs will destroy an entire ecosystem, for several marine organisms are associated with them.

The National Committee constituted for conservation and management of wetlands and mangroves also oversees the formulation and implementation of programmes of conservation, management of and research on coral reefs. State level steering committees have also been constituted for the formulation and implementation of the manage­ment action plan for the identified coral reefs, namely, Andaman and Nicobar, Lakshadweep, the Gulf of Mannar, and the Gulf of Kutch. The environment ministry has been identified as the national focal point of International Coral Reef Initiative (ICRI), Global Coral Reef Monitoring Net­work (GCRMN) as well as Coral Reef Degraded Action in the Indian Ocean (CORDIa). On the recommendation of the National Committee on Mangroves and Coral Reefs, the existing centre of the Zoological Survey of India at Port Blair has been designated as the National Institute of Coral Reef Research.