Fire prevention measures and large-scale bioenergy harvest in US West Coast forests could lead to 2-14% higher emissions over the next 20 years compared with current management practices. These findings, published online this week in Nature Climate Change, could have implications for the role of forest bioenergy in carbon mitigation policy in the US.

To investigate whether bioenergy harvest and forest thinning can meet the twin goals of reducing fire risk and carbon emissions, Tara Hudiburg and co-workers analysed inventory data for 80 forest types from US West Coast forests. They found that for the majority of ecoregions, the current carbon sink is sufficiently strong that it cannot be matched by substitution of fossil fuels by forest bioenergy.

The situation may change, however, if the carbon sink in these regions weakens below the current level owing to insect infestations, fire emissions or reduced primary production, say the authors. These findings emphasize the need to consider current forest carbon balance, local forest conditions and ecosystem sustainability in establishing effective mitigation policy.