FAO warns of 'alarming' loss of mangroves

ROME (AFP) — Mangrove swamps have shrunk by an "alarming" rate though their disappearance is slowing with improved awareness of their importance to biodiversity, the UN food agency said on Thursday.

"The world has lost around 3.6 million hectares (8.9 million acres) of mangroves since 1980, equivalent to an alarming 20 percent loss of total mangrove area," the Rome-based Food and Agriculture Organisation said in a report.

The total area covered by mangroves dropped from 18.8 million hectares in 1980 to 15.2 million in 2005, according to the survey "The World's Mangroves."

"Mangroves are important forested wetlands, and most countries have now banned the conversion of mangroves for aquaculture," said Wulf Killmann, a forestry expert at the FAO.

"They assess the impact on the environment before using mangrove areas for other purposes," he added.

"This has led to better protection and management of mangroves in some countries," he said, adding: "But overall, the loss of these coastal forests remains alarming. The rate of mangrove loss is significantly higher than the loss of any other types of forests."

Shrinking mangrove forests "can lead to severe losses of biodiversity and livelihoods, in addition to salt intrusion in coastal areas and siltation of coral reefs, ports and shipping lanes," Killmann said.

The main causes of the destruction of mangrove swampland include population pressure, conversion for aquaculture, agriculture, infrastructure and tourism, as well as pollution and natural disasters, FAO said.

Asia showed the greatest loss of more than 1.9 million hectares over the 25-year period of the study, mainly through land use changes.

Indonesia, Australia, Brazil, Nigeria and Mexico together account for about half of the world's mangroves.