Destruction of coral reefs make Chennai vulnerable to tsunamis, cyclones

C Shivakumar

Chennai:

Chennai is vulnerable to tsunamis and cyclones following the destruction of coral reefs, which is the nature’s defence against tsunamis, according to director of Zoological Survey of India K Venkatraman.

Speaking on the sidelines of a function to mark the celebrations of The International Day for Biological Diversity, he told Express that Chennai is vulnerable to cyclone as it has coral reefs which acts as a protective barrier has been destroyed.

“Coral reefs, also known as rainforests of the seas, are the frontline protectors followed by mangroves and Chennai does not have any and that is the reason it was affected by the tsunami and had high casualty when the cyclone hit the coast,” said Venkatraman.

S Balaji, chief conservator of forests and Trust Director of Gulf of Mannar Biosphere Reserve Trust, said that the tsunami never had an impact on Gulf of Mannar as it was shielded by coral reef and mangroves but the worst affected was Cuddalore whose coral reef has been destroyed and Chennai.

Coral reefs are found in shallow waters with an ideal temperature range of between 20 degree and 30 degree Celsius. The reefs are structures that have formed over hundred, thousands or even millions of years by tiny organisms called polyps, which produce skeletons of calcium carbonate.

The reef building corals contain symbiotic, microscopic, photosythesising algae called zooxanthallae. While the polyps provide the algae with carbondioxide, the algae uses the sunlight to convert it into oxygen.

Interestingly, the coral reefs as slowly dying and Braulio Ferriera de Souza, executive secretary of Secretariat to the Convention on Biological Diversity warned that if no steps are taken to protect them they would be the first eco-system to disappear from the world.

He said reefs around the world are subjected to thermal stress, which is regular bleaching from warmer temperatures. Coral reefs can't recover from this type of chronic exposure. He also highlighted green house gases damaging reefs because the increased CO2 settles in the oceans and alters the chemistry of the water, making it more acidic.