Times of India Reports - Greens cry foul over cultivation of seaweeds, say corals face danger

Publication: The Times Of India Chennai; Date: Jul 24, 2010; Section: Times Region; Page: 8


Greens cry foul over cultivation of seaweeds, say corals face danger
Padmini Sivarajah | TNN

Madurai: There is strident demand from environmentalists for immediately stopping the artificial cultivation of the seaweed, “kappaphycus alvarezii”, a species of red alga in the sea in Ramanathapuram, Kanyakumari and Thoothukudi districts. The Coastal Peoples’ Federation (CPF) has alleged that the coral reefs in this region were in danger of destruction because of these seaweeds.

CPF convenor M Pushparayan told TOI that the alga grows two meters long and is green or yellow in colour. It grows rapidly and is known to double its biomass in 15 days. The chemical carrageenans extracted from this alga is used in a variety of commercial applications like gelling, thickening and stabilizing agents in food products such as frozen desserts and also in pharmaceuticals and cosmetics.

The alga was first introduced in the Gulf of Mannar region by a Philippine soft drink manufacturer in 1995. Firms like the Aquaculture Foundation of India and even the Gulf of Mannar (GoM) Biosphere Reserve Trust, promoted this as an alternative employment to fishing folk, particularly for women, after the tsunami in 2004.

The GoM is a rich biosphere which is inhabited by 3,600 species of marine life forms including corals, sea grass, molluscs, turtles and even whales. Now all these animals are endangered by the uncontrollable growth of this alga which is destroying the corals, says CPF, which has demanded action under the Wild Life Protection act of 1972 against the artificial cultivation of the kappaphycus seaweed.

Dr K Kumaraguru, head of the department of environmental study and Marine and Coastal studies, Madurai Kamaraj University, told TOI that the alga, which was not a native species but an introduced one, would indeed disturb the ecological conditions of the GoM if they settled on the coral reefs. The coral reefs have a symbiotic relationship with a particular photosynthesizing alga which settles on them.

The coral reefs depended on these algae for their food. But, the kappaphycus alga which is a fast growing, resilient species, settles on the coral reefs and disrupts the photosynthesis of the alga on the coral reef. The reef would in turn expel the alga if it does not photosynthesize, which would result in bleaching of the coral reefs and ultimately their death. This would be detrimental to the ecosystem, which was already suffering due to various reasons including mixing of sewage in the sea, said Kumaraguru.

AGAINST NATURE: Rameswaram fishermen with the harvested seaweed