The findings showed that the number and range of species of birds in rehabilitated tropical forest recovered to levels very close to those found in unlogged forest after just 15 years. Forest that was left to regenerate naturally after selective logging showed less diversity.

"Birds have proven to be a fairly reliable indicator of how other groups such as plants and insects respond to habitat management, so this suggests that other groups might also benefit equally quickly if logged rainforests were managed effectively," says Dr David Edwards (Faculty of Biological Sciences).

The team compared biodiversity of birds in three adjoining areas of forest in north-eastern Borneo. One is the oldest and largest area of rehabilitated forest in the tropics, logged around 20 years ago, with over 10,000 ha actively rehabilitated for the past fifteen; another is a naturally regenerating area of forest, logged at the same time; and the third, a conservation area of unlogged forest.

Dr Edwards is calling for the inclusion of biodiversity-friendly strategies in carbon trading schemes to ensure that carbon offsetting projects support, rather than undermine, rainforest conservation.

Trees in tropical climates soak up large amounts of carbon dioxide, so restoring logged forest through re-planting could also be used in carbon trading. Currently, large plantations of one type of tree, such as Eucalyptus, are popular as carbon offsetting or sequestration projects - ie, those that capture carbon dioxide from the atmosphere and store it in 'carbon sinks' such as forests, soils and oceans - because they also provide commercial benefits.  However, these single species plantations do not support tropical biodiversity.

Dr Edwards has shown that managed restoration of logged forest - which can also be used for carbon offsetting - brings biodiversity virtually back to pre-logging levels within 15 years, much quicker than forest left to regenerate naturally.

"Our research shows that it's possible to have both carbon sequestration and biodiversity benefits within the same scheme," he says. "This could act as a strong incentive to protect logged forests under threat of deforestation for oil palm and other crops. Selectively logged rainforests are often vulnerable because they're seen as degraded, but we've shown they can support similar levels of biodiversity to unlogged forests."

The research is published in Conservation Biology Volume 23, Issue 5 (October 2009) and was funded by the Leverhulme Trust.