/ 7 January 2005

How the mangrove shield was lost

As the clear-up from the Asian tsunami starts and the full damage is assessed, there is growing consensus among scientists, environmentalists and Asian fishing communities that the impact was considerably worsened by tourist, shrimp farm and other industrial developments that have destroyed or degraded mangrove forests and other natural sea defences.

Reports this week from India, Sri Lanka, Indonesia and Malaysia suggest the worst damage has been in places with no natural protection from the sea.

According to Professor MS Swaminathan, India’s leading agricultural scientist who is chairing a government inquiry into coastal developments, the mangrove forests in the Pitchavaram and Muthupet regions of Tamil Nadu acted like a shield and bore the brunt of the tsunami.

”But in other areas, like Alappuzha and Kollam where the forests have been cut down and there is sand mining and developments, the devastation has been more widespread. The dense mangrove forests stood like a wall to save coastal communities living behind them,” says Swaminathan.

While most Asian countries have strong environmental protection laws governing coastal developments and protecting coastal forests, these are widely ignored by the powerful tourist and aquaculture industries, which have rapidly encroached on to beaches and cleared the inter-tidal areas to provide better views, wider beaches or the brackish water environment in which shrimps and prawns thrive.

”The full fury and wrath of the waves were felt in areas where nature’s green belts of coral reefs and mangroves no longer exist or were never present in the first place,” says a spokesperson for Walhi, Indonesia’s leading environment group in Jakarta.

”Here is a valuable lesson for all governments. Coastal zones and green belts such as mangroves, coral reefs and other natural barriers must be protected, regenerated and managed in a sustainable way,” says the spokesperson. ”It is only through having such natural defences that coastal communities can be protected in the long run from a repeat of what struck these regions.”

Many studies have found that mangroves help protect coastlines from erosion, storm damage and wave action by acting as buffers and catching alluvial materials. They also protect coral reefs and seagrass beds from damaging siltation and pollution.

But, says the United States-based Mangrove Action Project (Map) — a network of NGOs, scientists and academics working in 60 countries — mangrove forests may be disappearing faster than rainforests. ”Vast tracts have been cleared in the past 20 years,” says a Map spokesman.

According to Map, mangroves once covered up to 75% of the coastlines of tropical and sub-tropical countries. Today, less than 50% remain, and of this more than half is degraded.

In less than 20 years between 1975 and 1993, Thailand’s mangrove areas almost halved, reports show, while India may have destroyed up to half of its mangroves between 1963 and 1977. — Â