Carbon offset potentials of four alternative forest management strategies in Canada: a simulation study

Using an Integrated Terrestrial Ecosystem C-budget model (InTEC), wesimulated the carbon (C) offset potentials of four alternative forest management strategies in Canada: afforestation, reforestation, nitrogen (N) fertilization, and substitution of fossil fuel with wood, under different climatic and disturbance scenarios. C offset potential is defined as additional C uptake by forest ecosystems or reduced fossil C emissions when a strategy is implemented to the theoretical maximum possible extent. The simulations provided the following estimated gains from management: (1) Afforesting all the estimated ? 7.2 Mha of marginal agricultural land and urban areas in 1999 would create anaverage C offset potential of ? 8 Tg C y^-1 during 1999-2100, at a cost of 3.4 Tg fossil C emission in 1999. (2) Prompt reforestation of all forest lands disturbed in the previous year during 1999-2100 would produce an average C offset potential of ? 57 Tg C y^-1 for this period, at a cost of 1.33 Tg C y^-1. (3) Application of N fertilization (at the low rate of 5 kg N ha^-1 y^-1) to the ? 125 Mha of semi-mature forest during 1999-2100 would create an average C offset of ?58 Tg C y^-1 for this period, at a cost of ?0.24 Tg C y^-1. (4) Increasing forest harvesting by 20% above current average rates during 1999-2100, and using the extra wood products to substitute for fossil energywould reduce average emissions by ?11 Tg C y^-1, at a costof 0.54 Tg C y^-1. If implemented to the maximum extent, the combined C offset potential of all four strategies would be 2-7 times the GHG emission reductions projected for the National Action Plan for Climate Change (NAPCC) initiatives during 2000-2020, and an order of magnitude larger than the projected increase in C uptake by Canada's agricultural soils due to improved agricultural practices during 2000-2010. [ABSTRACT FROM AUTHOR]