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4.5.6. Forest Products
This section presents the opportunities offered by forest products as a recyclable
store of carbon and a renewable source of fibers for the mitigation of climate
change. Policy options to account for these wood product pools are discussed
in Section 6.2.2.
In 1996, the world's forests produced 3.4 billion m3 of harvested roundwood.
About 1.9 billion m3 (56 percent) of this harvest was fuelwood; the remainder
(1.5 billion m3) was industrial roundwood (e.g., sawlogs and pulpwood). The
industrial roundwood corresponds to a harvesting flux of about 0.3 Gt C yr-1.
Developed countries account for 70 percent of total world production and consumption
of industrial wood products (FAO, 1999).
The timber that is harvested is converted into a wide variety of wood products
(Skog and Nicholson, 1998). The carbon in the wood is fixed in products until
they decay or are burned (i.e., for energy production) and the carbon is subsequently
released back into the atmosphere. Models are available to assist in developing
estimates of carbon fate in wood products, depending on their initial size,
quality, and industrial utilization (Row and Phelps, 1996; Apps et al.,
1999b). With increasing industrial use of wood, the amount of carbon fixed in
wood products will raise proportionally. There are several ways to positively
influence the carbon balance:
- Shifting the product mix to a greater proportion of wood products.
Manufacturing and transport of wood products requires less fossil fuel than
energy-intensive construction materials such as aluminum, steel, and concrete
(Matthews et al., 1996). Recent comparisons show that the production
of steel and concrete as building material requires up to two times more energy
than wood-based product-with concomitant greater generation of GHGs. Increased
use of solid timber, engineered wood and wood-based panels, paper, and fuels
displaces energy-intensive materials (cement, steel, bricks, and plastics)
in two main ways. On one hand, it increases the amount of carbon stored in
wood products, particularly those with long life spans. On the other hand,
it reduces emissions during production processes. The use of by-products (wood
fuels) for energy generation in production processes has an additional positive
impact on the overall carbon balance.
- Increasing the useful life of products. Extending the life of wood
products implies not only a longer service life but a longer carbon sequestration
period and less energy consumption for their replacement through other new
materials. The service life of wood products can be extended by using the
appropriate timber species for particular end uses, applying constructive
or chemical wood protection against fungi and insect attack, and wise use
of the products themselves.
- Increasing product recycling. Wood and paper products are among
the most commonly used materials for recycling into new products and fuels.
Utilization of recovered wood in the paper industry and power plants is a
good example. In Europe, for example, recovered paper accounts for 40 percent
of annual paper production and is predicted to increase to 45 percent in the
future. An increase in the number of times a material is recycled and the
recycling of more wood and paper products will enhance the storage of carbon
and reduce emissions.
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