ENVIRONMENT: Why Save the Forests? Fear of big waves is no reason to plant mangroves.

Byline: Jason Overdorf and Eric Unmacht

In the aftermath of a natural disaster like December's tsunami, some stories have happy endings. V. Selvam's began when the giant waves came crashing into the mangrove forest of Pichavaram on India's Tamil Nadu coast. Selvam, a biologist who had been working to restore the forests, made his way to a nearby village as fast as he could, expecting the worst. Instead, he found relieved villagers regaling him with anecdotes. Eyewitnesses told Selvam that the mangroves had channeled water into lagoons and through canals, sparing the settlements meters from the shore. "I couldn't believe it," he says.

Similar anecdotes from all over the tsunami-affected region have had a special appeal to environmentalists and conservationists, who argue that if it weren't for the destruction of mangroves and coral reefs, which form natural barriers to waves, the death toll might have been far lower. Some of the hardest-hit countries have taken this admonition to heart and made mangrove restoration a pillar of their restoration efforts. Indonesia has promised to spend $22 million to replant 600,000 hectares of mangroves along its damaged coastline. The state of Kerala in southern India announced a plan to spend $8 million to create a protective barrier of mangrove plants. And forest officials in Thailand, Malaysia and Sri Lanka are evaluating similar schemes. The problem is that the idea of developing physical barriers, natural or otherwise, to protect against future tsunamis is "pie in the sky," says Doug Masson, an oceanographer at Southampton University in England.

There's no denying that mangroves did save some villages, like those on the Indonesian islands of Sabang, Nias and Simeulue, which were spared the worst damage even though they were close to the earthquake's epicenter. The faulty logic comes in generalizing these experiences to the entire region. For one thing, mangroves don't grow everywhere--only 10 to 12 percent of India's coastline and 25 percent of Indonesia's, for instance, naturally support mangroves. If 20 percent of these forests had been lost to development between 1980 and 2000, as the United Nations' Food and Agriculture Organization says, or even 50 percent, as some conservation groups insist, that would have left only a small fraction of coastlines vulnerable.

The forests, too, cannot be planted just anywhere. The Indonesian government is considering laying a belt of the trees around the entire province of Aceh, which ...