World efforts to slow deforestation should do more to address underlying causes such as rising demand for crops or biofuels.

This has become imperative to widen the UN focus on using trees to fight climate change, a study said  last Monday.

It said that series of projects to protect forests had had limited success in recent decades with UN figures showing that 13 million hectares of forest were lost every year from 2000 to 2009, an area equivalent to the size of Greece.

The report by the International Union of Forest Research Organisations (IUFRO) suggested that the current UN-led efforts to protect forests had too narrow a focus on promoting trees as stores of carbon dioxide, the main greenhouse gas.

“Our findings suggest that disregarding the impact of forests on sectors such as agriculture and energy will damage any new international efforts whose goal is to conserve forests and slow climate change,’’ said Jeremy Rayner, who chaired the IUFRO

panel and is a professor at the University of Saskatchewan.

Deforestation accounts for perhaps 10 per cent of all emissions of greenhouse gases from human activities, and trees soak up carbon as they grow but release it when they burn or decay.

The IUFRO study said a key problem was that deforestation, from the Amazon to the Congo, was often caused by economic pressures.

Just as a popular global brand of cookies, for instance, uses palm oil grown on deforested land in Indonesia.

IUFRO urged policies of “embracing complexity” to help protect forests, including educating consumers, rather than rely on a one-size-fits-all mechanism such as carbon storage.

It called for better efforts, for instance, to aid indigenous peoples, whose livelihoods depend on healthy forests.

“Among promising measures are amendments to the U.S. Lacey Act, which makes it illegal to import wood known to come from stolen timber.

“Brazil, for instance, has enacted procedures to tackle deforestation in the Amazon,’’ it said.

The IUFRO report will be issued at UN talks in New York this week marking the start of the UN’s International Year of Forests.

Almost 200 nations agreed at a meeting in Cancun, Mexico, last month to step up efforts to protect forests with a plan that aims to put a price on the carbon stored in trees, while helping indigenous peoples and promoting sustainable use.

Authors of the IUFRO study said that the UN plan, known as REDD+, was promising.

“Our worry is that this won’t be enough,”Benjamin Cashore, a forestry expert at Yale University and an IUFRO author, told reporters.

He said that governments often simplistically placed too much faith in the latest idea, like carbon markets.

He said many past schemes had failed to brake deforestation, such as boycotts of some timber in the 1980s by rich consumers, or an international tropical timber agreement that sought to unite producers and consumers.