Stands of casuarina — a tree species not native to India — dot beaches along Ernakulam’s Vypeen area. The trees were planted as part of a coastal afforestation programme, but what does an exotic tree do in a region where grass and creepers form its vegetation?
The trees were planted to arrest sea-caused soil erosion, said Anaz M.A., Assistant Conservator of Forest (Social Forestry, Ernakulam). “Along with funding from Kochi LNG, the Forest Department has planted casuarina in four hectares at Puthuvype,” he added.
While around 6,000 saplings were planted, another thick stand of casuarina trees line the beach near the Beach Link Road in Vypeen’s Elamkunnapuzha panchayat. Further north on Chappa beach, around 10,000 saplings were planted on a one-kilometre stretch with the help of Theera Samrakshana Vana Samrakshana Samiti, said Santhosh K.P., section forest officer (Social Forestry, Vypeen).
However, planting casuarina along beaches is not advisable though it can be planted in the hinterlands and inward side of coasts, said biologist Jayashree Vencatesan of Chennai’s Care Earth Trust. She studies coastal vegetation and works on issues of conservation and sustainable use of biodiversity and ecological restoration.
“Casuarina interferes with the integrity and dynamics of coasts. They also severely impact dune vegetation,” she said.
Across India’s east and west coasts, including Kerala, herbs dominate the natural dune vegetation, according to a study by Goa’s National Institute of Oceanography (NIO). They include perennial grass like Ravan’s moustache ( Spinifex littoreus ) and creepers such as beach morning glory ( Ipomoea pescaprae ). Though Kerala’s coasts alone are home to 37 such species of sand dune flora, it is still low compared to other coastal States. The reasons are many, claim studies.
More than 60% of Kerala’s shoreline is threatened by erosion, and sea walls along more than 70% of its coasts affect dune vegetation and micro flora. Studies show that casuarina stands on the beach also interfere with the nesting of sea turtles, and the Tamil Nadu Forest Department is now removing casuarina from such areas, said K. Saravanan of the Coastal Resource Centre in Chennai.
