CARBON BUDGET OF UNITED STATES FORESTS
How much carbon is in forest products?
A: Carbon in wood harvested from forests
ends up in a variety of uses, from bring sequestered in lumber in
buildings or furniture for a century or more, to quickly being released
into the atmosphere as logging debris is burned in preparation for
planting. We consider four general categories for the fate of wood:
products, landfills, energy production, and decomposition without
energy production. Carbon in historical removals was estimated beginning
In 1995, a net annual average of about 37 million metric tons (MMT)
C/yr. was being stored in products and landfills (Heath and others
1995) , which is approximately two-fifths of the carbon being sequestered
in forest trees of the U.S. (Birdsey and Heath 1995). An additional
50 MMT C/year is emitted when wood is burned for energy. Because
of the large magnitude in the wood burned for energy category, how
one accounts for emissions from wood used as a substitute for fossil
fuels can have a great influence on how forests are managed for
carbon sequestration. See Figure 1 for carbon flux in disposition
categories over time.
Harvests are projected to continue to increase under "business-as-usual"
assumptions about population and society over the next 50 years.
Approximately 20 MMT C/yr. will be stored in forest products, and
about the same amount will be stored in landfills. If all harvesting
in the United States ceased in 1990, the annual average flux of
carbon emissions from existing products would be about 53 MMT/yr.,
and about 12 MMT/yr. from landfills.
The U.S produced about 20% of the sawnwood, 25% of wood-based panels,
30% of paper and paperboards, and about 5% of the fuelwood as compared
to the rest of the world in 1990 (Brooks 1993). This roughly means
that C in wood products in the world is currently increasing about
100 MMT C/yr.
(insert Figure 4 from the BANFF.wdp
SOURCE: Heath, L.S., R.A. Birdsey, C. Row, and
A.J. Plantinga. 1996. Carbon pools and flux in U.S. forest products.
In: Forest Ecosystems, Forest Management, and the Global Carbon
Cycle, (M.J. Apps and D.T. Price, eds). NATO ASI Series I: Global
Environmental Changes, Volume 40, Springer-Verlag, p. 271-278.