Global Forest Carbon Budget (tons of C/y) Carbon sink or source (-) 2000-2007 Boreal Forests (like Canada, northern Alaska, and Russia) 551 million tons Temperate Forest (like much of the United States) 860 millon tons Tropical Intact (not heavily disturbed) 1.1 billon tons Total sink established forests 2.5 billon tons   Tropical forests that have been cut down but are now regrowing 1.9 billon tons Emissions from Tropical that have been cut down and not replated -3.1 billon tons Tropical land-use emission -1.2 billion tons Global forest sink 4.4 billion tons Global net forest sink (total carbon captured by forest minus the total carbon lost when forest are cut down and not replanted) 1.3 billion tons Pan et al. 2011 Science 333:988-993

Global Carbon Fluxes Pan et al. 2011 Science 333:988-993

U.S. Forest Carbon Balance- (0 is neutral- rising line represents carbon being released) 16.5 billion tons stored; 220 million tons per year 46 billion tons released, 196 million tons per year Fig. 4.The carbon balance of the U.S. forest sector shows that clearing for agriculture, pasture, development, and wood use released ∼42 000 Tg of carbon from 1700 to 1935, and recovered ∼15 000 Tg of carbon from 1935 to 2010. Adapted and reprinted from Birdsey et al. 2006, with permission from the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. McKinley et al. 2011. Ecological Applications 21:1902–1924

Carbon storage in the USA Zhu, Zhiliang, and Reed, B.C., eds., 2012, Baseline and projected future carbon storage and greenhouse-gas fluxes in ecosystems of the Western United States: U.S. Geological Survey Professional Paper 1797, 192 p. (http://pubs.usgs.gov/pp/1797/.)

Carbon flux

USDA Forest Service. 2010. Carbon storage in US forests, by state, sub-region, and ownership group. Available online at www.fia.fs.fed.us/Forest%20Carbon/docs/Total%20Carbon%20storage%20in%20US%20Forests%2020101028.xls [Only forest land included,.}

PNW Old Growth Reserves Smithwick, Erica AH, et al. "Potential upper bounds of carbon stores in forests of the Pacific Northwest." Ecological Applications 12.5 (2002): 1303-1317.

PNW Old Growth Reserves Smithwick, Erica AH, et al. "Potential upper bounds of carbon stores in forests of the Pacific Northwest." Ecological Applications 12.5 (2002): 1303-1317.

Carbon accumulation with active forest management can increase C, but… Cumulative carbon (Mg/ha) 0 20 40 60 80 100 McKinley et al. 2011. Years

…declines and recovers when starting with Old Growth forest Cumulative carbon (Mg/ha) Carbon balance from two hypothetical forest management projects with different initial ecosystem carbon stocks. Cumulative carbon stocks in both ecosystems, carbon removed from forest for use in wood products (long [L]- and short-lived [S]), substitution, and biomass energy (bio-energy) are shown for two scenarios: (A) land that has been afforested and (B) a forest with high initial carbon stocks. Carbon stocks for trees, litter, and soils are net carbon stocks only. Both scenarios are harvested in 40-year intervals. This diagram assumes that all harvested biomass will be used and does not account for logging emissions. Gains in carbon sequestration occur in two ways; (1) increasing the average ecosystem carbon stock (panel A; tree biomass), and (2) accounting for carbon stored in wood products in use and landfills, as well as preventing the release of fossil fuel carbon (counted as stored carbon) via product substitution or biomass energy (panel A; landfill, short- and long-lived products, and bio-energy). However, carbon can be lost for some time (panel B) when forests with substantial carbon stocks are harvested (e.g., some old-growth forests) until carbon stocks can accrue via sequestration in landfills, products, and with substitution effects. (The figure is adapted from the 2007 IPCC report.) McKinley et al. 2011. Ecological Applications 21:1902–1924

Managing 2nd growth to increase carbon storage 0 60 120 180 Forest age (years) Carbon Storage Rate vs Total Storage Carbon Industrial Forestry Harvest Age Increase rotation length Reduce harvest intensity Leave snags and coarse woody debris Minimize soil disturbance Slide: Paul Fischer 1 Canadell and Raupach 2008. Science 320: 1456-7.

Harvest and carbon pools 0 60 120 180 Carbon Wood products Carbon with NO HARVEST Carbon with HARVEST But compared to no harvest, it is clear that we can do better. Forest age (years) Slide: Paul Fischer