Forest carbon

COPENHAGEN (Reuters) - The United States has pledged $1 billion as part of a $3.5 billion scheme as initial financing toward slowing deforestation, a major contributor to climate change, a U.S. government statement said on Wednesday.

Defining how a forest can generate carbon credits could be the one landmark agreement coming out of the UN climate talks in Copenhagen.

At this week's global climate talks, some rich nations are prepared to urge more lenient accounting practices to hide a portion of their fossil fuel carbon emissions using their trees, environmentalists say.

Destruction of forests — burning or cutting trees to clear land for plantations or cattle ranches — is thought to account for about 20 percent of global emissions. That's as much carbon dioxide as all the world's cars, trucks, trains, planes and ships combined.

Carbon offset schemes like REDD have been a big part of the Copenhagen negotiations so far, but in practice they can go horribly wrong, reports Angela Dewan