Alister Doyle, Environment Correspondent
OSLO (Reuters):
COSTS OF safeguarding the world's fast-disappearing coral reefs and mangroves are small compared to the benefits they provide from tourism to fisheries, the U.N. Environment Programme (UNEP) said on Tuesday.
The report, part of a recent trend trying to place a value on the natural world, said that pollution, global warming and expanding human settlements along coasts were among mounting threats to reefs and mangroves.
"Day-in and day-out and across the oceans and seas of the world nature is working to generate incomes and livelihoods for millions if not billions of people," UNEP executive director Klaus Toepfer said in a statement.
The report, to be issued at a conference in Paris, estimated that intact coral reefs were worth US$100,000-US$600,000 per sq km (0.3861 sq mile) a year to humankind and a sq km of mangroves US$200,000-US$900,000 a year. Under another survey, coral reefs in the Caribbean were estimated to be worth from US$2,000 a year in remote areas to US$1 million beside a tourist resort where it drew scuba divers.
"Most benefits from coral reefs and mangroves arise from fisheries, timber and fuelwood, tourism and shore protection," it said.
Corals and mangroves protect coastlines from erosion caused by storms, for instance. The report said it was unclear, however, if they had shielded Indian Ocean coasts overall from the disastrous tsunami on December 26, 2004.
By contrast, the cost of protecting a sq km of coral reef or mangrove in a marine park was just US$775 a year, it reckoned.
It said that all estimates were based on vague data and had to be treated with caution but indicated that better protection made sense in a little-tested branch of ecosystem economics.
DAMAGE
It said that about 30 per cent of reefs were severely damaged and that 60 per cent could be lost by 2030. About 35 per cent of mangroves had already disappeared due to logging, disease and conversion to fish farms.
UNEP's Toepfer said the report should make people "think twice about the pollution, climate change, insensitive development and other damaging practices that are undermining the economic basis for so many coastal communities worldwide."
In trying to assess the value of reefs, for instance, the survey said that costs of building a concrete breakwater in the Maldives to replace a damaged reef had been US$10 million per km.
The report, produced by UNEP with the International Coral Reef Action Network and the World Conservation Union, also estimated that reef fisheries were worth between US$15,000 and US$150,000 per sq km a year.
Fish caught for aquariums were worth US$500 a kilo (2.2 lbs) against US$6 for fish caught as food.
