How the mangrove shield was lost

Posted: 17 January 2005

Author: John Vidal

Powerful business interests left Asian coastal protection in tatters before the tsunami, reports John Vidal.

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 which 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 and that communities living behind intact mangrove forests in particular were largely spared.

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 Prof Swaminathan.

"The impact was mitigated and the lives and property of the communities inhabiting the region were saved. It is now found that wherever the mangroves have been regenerated, the damage due to the tsunami is minimal," he says.

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 onto 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 spokesman for Walhi, Indonesia's leading environment group in Jakarta. Walhi's Aceh province director was killed in the tsunami.

"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 a spokesman in Jakarta.

"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."

"In areas where there were 'green belts', the damage was less or none at all," says Hemantha Withanage, of the Centre of Environmental Justice in Sri Lanka. "In many parts of the affected areas where dense mangroves and coral reefs once acted as natural buffers between the sea and coast, other developments have taken place - from hotels, shrimp farms, coastal highways, housing and commercial development."

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 sea grass beds from damaging siltation and pollution.

But, says the US-based Mangrove Action Project (Map) - a network of 400 NGOs and more than 250 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 in India, Thailand, Bangladesh and Indonesia," says a Map spokesman.

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

In less than 20 years between 1975 and 1993, Thailand's mangrove area was almost halved, reports show, while India may have destroyed as much as half of its mangroves between 1963 and 1977.

logo Guardian Unlimited © Guardian Newspapers Limited 2005. This article was first published by The Guardian, (Thursday, January 6, 2005). All rights reserved. Reproduced with kind permission.