2.4.2.2. Wood Products
Wood products in use are part of a full forest sector carbon balance. Globally,
about 3.4 billion m3 of wood is harvested per year, excluding wood burned on-site
(FAO, 1997b), and harvest rates are expected to increase at 0.5 percent per
year (Solberg et al., 1996). Of the total harvest, about 1.8 billion
m3 yr-1 is fuelwood, mainly from the tropics. Most of the harvest in the boreal
and temperate zone is industrial roundwood. About one-half to two-thirds of
the raw wood finds its way into wood products; the rest is used as energy or
is otherwise lost. The annual production of wood materials therefore corresponds
to a harvest flux of about 1.6 billion m3, translating to a gross flux into
wood products of about 0.3 Gt C yr-1.
The long-term effectiveness of carbon storage in wood products depends on the
uses of wood produced through project activities. In projects that stop logging
(and perhaps those that stop deforestation, if some of the wood cut during deforestation
entered the wood products market), the change in the wood products pool would
be negative and would thus offset some of the carbon benefits from the project;
this effect would have to be accounted for. In plantation projects, wood that
goes into medium- to long-term products (e.g., sawn timber for housing, particle
board, paper) represents additional carbon storage. Several (modeling) methods
exist for accounting for the storage of long-lived wood products; these methods
have been used to calculate the net changes in stocks in several countries (Pingoud
et al., 1996; Nabuurs and Sikkema, 1998; Skog and Nicholson, 1998; Winjum
et al., 1998; Apps et al., 1999). These methods account for inputs
of new products to the pool as well as decay, disposal in landfills, oxidation,
and retirement of products from past use, accumulated as far back as individual
country's records allow. An IPCC expert group for the land use and forestry
sector of the guidelines for GHG inventories completed a report on a description
and evaluation of the approaches available for estimating carbon emissions or
removals from forest harvesting and wood products (Lim et al., 1998).
If one of the additional activities (see Section 4.4.5)
includes carbon in wood products, a method for monitoring changes in the carbon
of that compartment will be needed. Monitoring of wood products is possible
through national and international statistics on harvesting and trade. The net
build-up of carbon in products might be derived from estimates of average lifetimes
for different wood products. Keeping track of the wood products stemming from
lands under Article 3.3 or 3.4 will be extremely difficult, however. The only
practical approach may be to use estimates that are based on data from other
forests.
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