Estimates of carbon storage in wood products following land clearing

Biofuel production may lead to indirect land use change (ILUC) by displacing food production onto new cropland. The clearing of such land for expanding agriculture would result in large amounts of carbon emissions as plant biomass and soil carbon are removed or burned. The fraction of cleared forest biomass that is assumed to remain stored as harvested wood products may have a significant impact on global modeled ILUC emissions.

In this paper, we review a previous attempt to determine storage of forest carbon in wood products in the U.S. and provide our own estimates of this fraction for developed and developing countries. Relying on data from the U.S. Forest Service on logging operations, wood milling, and wood product allocation and U.S.D.A. estimates on wood production retention, we calculate that, in the U.S., 10% of biomass removed from forests through land clearing or logging is retained in wood products after 30 years.

We use two parallel approaches to calculate carbon storage in wood products in the tropical developing world. In the first approach, we estimate deforestation rates and use F.A.O. data on wood production to calculate carbon storage in wood products as a fraction of removed forest biomass. In the second, simpler approach, we extrapolate this fraction from the U.S. based on the fuelwood/wood products ratio in each region. In the developing world, where a large proportion of logged wood is burned as fuel, wood products only store ~1–3% of removed forest biomass.

As many ILUC models currently do not account for carbon storage in wood products, and at least one model substantially overestimates this parameter, this paper provides the necessary basis for a significant input in future predictions of biofuel-driven land use change emissions.