The total forest biomass carbon sink - the carbon sequestered each year by ECE Region forest ecosystems - amounts to 255 million tonnes of carbon per year between 2005 and 2010. The ECE forests are a significant carbon sink although there is uncertainty over the exact size of the sink, and its underlying causes. Forest management has the possibility to continuously maintain a carbon stock over larger forest estates, while at the same time sustainably producing wood products and biomass for bioenergy.