In the run-up to next month's climate-change treaty negotiations in Copenhagen, there is a pressing need to inform policy discussions about the importance of carbon management of northern boreal forests, as well as of tropical forests.

Boreal carbon pools account for more of the overall carbon stock than tropical forests — a minimum of 559–703 gigatonnes, compared with 375–428 gigatonnes — and store twice as much carbon per unit area (see R. T. Watson et al. IPCC Special Report: Land-Use Change and Forestry Cambridge Univ. Press; 2007, and E. S. Kasischke Fire, Climate Change, and Carbon Cycling in the Boreal Forest Springer; 2000).

In tropical forests, carbon flux is equilibrated between sequestration in growing trees and loss from decay of dead trees. Boreal ecosystems, on the other hand, accumulate carbon over millennia in soils, peat and sediments and under permafrost, because low temperatures prevent biotic breakdown and release of accumulated carbon.

The large carbon stocks and sequestration potential of tropical and boreal regions are under threat from deforestation and habitat degradation. The rapidly expanding human industrial footprint in boreal regions in Canada and Russia, for example, will increase the risk of releasing emissions from the vast carbon stores of these areas. To reduce climate disruption, efforts are needed at international, national and regional levels to develop incentives for encouraging protection of these intact ecosystems.