Mangrove loss ‘left Burma exposed’

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Destruction of mangrove forests in Burma left coastal areas exposed to the devastating force of the weekend’s cyclone, a top politician suggests.

ASEAN secretary-general Surin Pitsuwan said coastal developments had resulted in mangroves, which act as a natural defence against storms, being lost.

At least 22,000 people have died in the disaster, say state officials.

A study of the 2004 Asian tsunami found that areas near healthy mangroves suffered less damage and fewer deaths.

Mr Surin, speaking at a high-level meeting of the Association of South-East Asian Nations (ASEAN) in Singapore, said the combination of more people living in coastal areas and the loss of mangroves had exacerbated the tragedy.

“Encroachment into mangrove forests, which used to serve as a buffer between the rising tide, between big waves and storms and residential areas; all those lands have been destroyed,” the AFP news agency reported him as saying.

“Human beings are now direct victims of such natural forces.”

His comments follow a news conference by Burma’s minister for relief and resettlement, Maung Maung Swe, who said more deaths were caused by the cyclone’s storm surge rather than the winds which reached 190km/h (120mph).

“The wave was up to 12ft (3.5m) high and it swept away and inundated half the houses in low-lying villages,” the minister said. “They did not have anywhere to flee.”

Storm shelter

Mangroves have been long considered as “bio-guards” for coastal settlements.

A study published in December 2005 said healthy mangrove forests helped save Sri Lankan villagers during the Asian tsunami disaster, which claimed the lives of more than 200,000 people.

Researchers from IUCN, formerly known as the World Conservation Union, compared the death toll from two villages in Sri Lanka that were hit by the devastating giant waves.

While two people died in the settlement with dense mangrove and scrub forest, up to 6,000 people lost their lives in a nearby village without similar vegetation.

“Mangroves are a very dense vegetation type that grows along the shore,” explained Jeffrey McNeely, chief scientist for IUCN.

“Where the saltwater and freshwater meet, that is where the mangroves grow; they often extend from several hundred metres to a few kilometers inland.

“Especially in river deltas, mangroves prevent waves from damaging the more productive land that are further inland from the sea.”

Lowering defences

A recent global assessment found that 3.6 million hectares of mangrove forests had disappeared since 1980.

The study carried out by the UN Food and Agriculture Organization (FAO) said that Asia had suffered the greatest loss, with 1.9 million hectares being destroyed, primarily as a result of land use change.

It found that large-scale conversion of mangroves into shrimp and fish farms were among the main destructive drivers.

Other pressures included new development to accommodate the growth in the tourism sector and rising populations.

Mette Wilkie, a senior forestry officer for the FAO, said most of the mangroves in Burma had suffered as a result of being overexploited.

“There are very limited areas that you would describe as pristine or densely covered mangrove in the Irrawaddy area,” she said, referring to the region of Burma where Cyclone Nagris first made landfall.

“There are some efforts in place to try to rehabilitate and replant mangroves, but we do know that the loss rate is quite substantial still.

“During the 1990s, they lost something like 2,000 hectares each year, which is about 0.3% being lost annually.

“But that does not give you the whole picture because the majority of these tidal habitats are being degraded, even if they are not being completely destroyed.”