The Indian Ocean tsunami highlighted the life-saving benefits of mangrove forests along coastlines, officials and environmentalists say, leading some Asia nations to look at replanting trees lost in the tsunami as well as those earlier uprooted to make way for shrimp and fish farms.
Indonesia, for one, said this month that it will replant huge swathes of mangrove forest along its vulnerable coastline, restoring the natural barrier between water and land.
“The mangroves are extremely important in forming an effective barrier against any type of wave,” said John Pernetta, a project director for the United Nations Environment Program. “It takes the energy out of the wave, so while the forest itself will be trashed, it will protect the infrastructure behind it.”
Indonesia's forestry minister, Malam Sambat Kaban, said Indonesia had lost about 1.6 million acres of mangroves over the past several decades — or about 30 percent of its total — to commercial fish farms and other development.
In the northern province of Aceh on Sumatra, where more than 110,000 people were killed in the tsunami, the government plans to replant at least thousands of acres with the trees.
“The tsunami in Aceh made us see the need to speed up this process,” Kaban said.
Mangroves are a family of evergreen trees and shrubs that grow on stilt-like roots in dense thickets in coastal areas, providing both a barrier to extreme weather and a rich ecosystem for marine life.
Kaban said the reforestation plan would cost an initial $22 million, with planting due to start by April, and would be accompanied by outreach to local communities on the importance of preserving the mangroves.
“We will see the results in five years, and within 10 years they will be big and healthy,” he said. “With reforestation, we will ensure the peoples’ needs are still catered for. People should still be able to farm fish outside the area.”
Concern about 'plantation-style' approach
Some mangrove experts voiced caution, however, saying previous “re-greening” projects had in fact hurt mangrove ecosystems because they were done without sufficient preparation.
Alfredo Quarto of the U.S.-based Mangrove Action Project said restoration projects in Thailand had ripped out living mangrove trees to plant seedlings of a uniform type — a “plantation-style” approach that harmed biodiversity.
“They planted the mangroves in places where they didn’t grow, and sometimes they tore down healthy mangroves to put in their own ... it was a terrible job and had very low success,” Quarto said. “It might look like a success after the first year, but after you come back in two or three years everything is dead. You have to look at 20 year periods.”
Quarto said successful restoration almost always involved local communities rather than government bureaucrats, and that reintroducing different species of mangroves was the key to re-establishing the forests as viable ecosystems.
Tsunami defense preparations should include a range of coastal restoration projects including mangroves, sand dunes and indigenous fringe forests, all of which have suffered as humans move closer to the sea, he said.
Kaban said Indonesia knew mangroves were only part of its coastal defenses, and said the planting program would include other trees such as pine and almond.
He stressed that, after years of being seen as little more than a seaside pest, mangroves were increasingly important.
“The north coast of Aceh has good mangroves. In Simeuleu island, there are very good mangroves and it was the area with the smallest number of victims when the tsunami hit. The mangroves protected the island.”
Awareness elsewhere
The importance of mangroves was not lost on other South Asia countries as well. Below's a sampling of reactions after the tsunami.
Thailand: “Mangroves in Ranong and Phang Nga saved hundreds of people,” said Maitree Duangsawasdi, head of the Department of Marine and Coastal Resources, referring to two of Thailand’s six affected provinces in which thousands of people died.
“We need to rebuild those that were damaged and plant more of them and other trees like pines and coconuts along the coastline,” he said, adding that his department would finish a rehabilitation plan for mangroves and coral reefs next week.
Pernetta said about 80 percent of mangrove forests on Thailand’s eastern seaboard have been destroyed in the last few decades, most of it as a result of small-scale shrimp farming. The situation on the west coast, hit by the tsunami, was much better, with only about 20 percent destruction.
India: “Areas that had mangroves suffered the least destruction. In the Andaman and Nicobar islands, for instance, there are many places where mangroves and coral reefs are still intact. If they weren’t, it could have been much worse,” said Debi Goenka, an environmentalist with the Bombay Environmental Action Group.
“Tamil Nadu, on the other hand, suffered so much because it had no mangroves or coral reefs and most of the construction is on beaches or close to high tide areas.”
Sri Lanka: Officials are considering legislation to ban further destruction of mangroves and beach dunes and also to introduce laws compelling developers to replant and build artificial reefs. “It is definitely clear that some mangroves were damaged, but it is also clear that they also helped prevent further damage in areas where they still exist,” said Environment Minister A.H.M. Fowzie.
Vietnam: Miles of mangroves along its South China Sea coast, which is often hit by storms, have been cleared, Pernetta said, but the government is now trying to reverse the process by planting mangroves.
