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Life-cycle inventory (LCI) and life-cycle assessment (LCA) were used to provide quantitative assessments of the environmental impacts of forest management activities that are required to produce feedstock for wood products such as lumber, engineered panels, and pulp. Primary and secondary data were gathered for the Pacific Northwest Douglas-fir region of the United States to produce an attributional LCA that includes planting, growing, and harvesting trees that are destined for use in wood manufacturing. Using the Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) method, under average management conditions, forest operations can expect to generate from 10 to 18 kg C[O.sub.2] equivalent (C[O.sub.2] eq) per cubic meter ([m.sup.3]) of logs ready to leave the landing for the manufacturing facility, depending on the amount of forest residues that are piled and burned. This same cubic meter of log plus bark will have sequestered 960 kg C[O.sub.2] eq during its growth cycle, for a net greenhouse gas sink of 942 to 950 kg C[O.sub.2] eq per [m.sup.3]. Forest management impacts are from 1 to 13 percent of the total impacts from the cradle to gate for global warming potential and the potential to increase smog, eutrophication, and acidification. Upstream impacts associated with the production of herbicides are reflected in the ozone potential impact category. These LCA results can be used as upstream processes for wood manufacturers interested in developing Environmental Product Declarations for products that use these resources as inputs., The Consortium for Research on Renewable Industrial Material (CORRIM) has developed research protocols (CORRIM 1998) and methodologies that have been used to conduct a wide range of attributional life-cycle inventory [...]

Since its inception in 1996, the nonprofit Consortium for Research on Renewable Industrial Materials (CORRIM; www.corrim.org) has developed comprehensive environmental performance information on wood building materials consistent with International Organization [...]

The heightened interest in biofuels addresses the national objectives of reducing carbon emissions as well as reducing dependence on foreign fossil fuels. Using life-cycle analysis to evaluate alternative uses of wood including both products and fuels reveals a hierarchy of carbon and energy impacts characterized by their efficiency in reducing carbon emissions and/or in displacing fossil energy imports. Life-cycle comparisons are developed for biofuel feedstocks (mill and forest residuals, thinnings, and short rotation woody crops) with bioprocessing (pyrolysis, gasification, and fermentation) to produce liquid fuels and for using the feedstock for pellets and heat for drying solid wood products, all of which displace fossil fuels and fossil fuel-intensive products. Fossil carbon emissions from lignocellulosic biofuels are substantially lower than emissions from conventional gasoline. While using wood to displace fossil fuel-intensive materials (such as for steel floor joists) is much more effective in reducing carbon emissions than using biofuels to directly displace fossil fuels, displacing transportation fuels with ethanol provides the opportunity to also reduce dependence on imported energy. The complex nature of wood uses and how wood fuels and products interact in their environments, as well as the methods needed to understand these impacts and summarize the relative benefits of different alternatives, are discussed herein. Policies designed to increase biofuel use by subsidies or mandates may increase prices enough to divert biomass feedstock away from producing products, such as for composite panels, resulting in increased emissions from fossil fuel-intensive substitutes. Policies that fail to consider life-cycle implications are discussed, identifying their unintended consequences., The life-cycle inventory (LCI) data for the many different uses of wood reveal a hierarchy of different opportunities to reduce carbon emissions or increase energy independence, both being current national [...]

A deterministic spreadsheet model developed in an earlier Consortium for Research on Renewable Industrial Materials (CORRIM) project that calculates cost, fuel, and chemical outputs of forest management and harvesting activities was modified to include logic for systems used to recover forest residue. Two illustrative biomass recovery systems with variations were modeled. A system to recover residues after whole-tree harvesting operations was applied to a representative forest stand in the Inland West. Whole-tree chipping in an early thinning was applied to a representative forest stand in the Southeast United States. Emission factors and life-cycle outputs were developed for the systems through the SimaPro v7.3 model using one if its environmental impact methodologies called TRACI2. Most environmental outputs, including global warming potential, had a direct relationship to fuel consumption of the recovery systems. These outputs were subsequently used as inputs to life-cycle analysis in biofuel conversion facilities. Fuel consumption for recovery of residues from the log landing was 8.10, 12.0, and 16.0 liters per bone dry metric ton (BDmT) at haul distances of 48, 97, and 145 km, respectively. Corresponding fuel consumption for whole-tree chipping and hauling at these distances was 10.5, 16.0, and 21.5 liters/BDmT. Shuttling ground residue from the landing for reload and a subsequent long haul of 145 km increased fuel consumption 32 percent over the residue recovery base case. Shuttling loose residue for centralized processing with a long haul distance of 145 km increases fuel consumption by 86 percent over recovery directly from the landing., ********** The location, slope conditions, and ease of access of forest biomass supplied to biofuel plants are highly variable. Additional variability derives from the size and distribution of material in [...]

The different uses of wood result in a hierarchy of carbon and energy impacts that can be characterized by their efficiency in displacing carbon emissions and/or in displacing fossil energy imports, both being current national objectives. When waste wood is used for biofuels (forest or mill residuals and thinnings) fossil fuels and their emissions are reduced without significant land use changes. Short rotation woody crops can increase yields and management efficiencies by using currently underused land. Wood products and biofuels are coproducts of sustainable forest management, along with the other values forests provide, such as clean air, water, and habitat. Producing multiple coproducts with different uses that result in different values complicates carbon mitigation accounting. It is important to understand how the life-cycle implications of managing our forests and using the wood coming from our forests impacts national energy and carbon emission objectives and other forest values. A series of articles published in this issue of the Forest Products Journal reports on the life-cycle implications of producing ethanol by gasification or fermentation and producing bio-oil by pyrolysis and feedstock collection from forest residuals, thinnings, and short rotation woody crops. These are evaluated and compared with other forest product uses. Background information is provided on existing life-cycle data and methods to evaluate prospective new processes and wood uses. Alternative management, processing, and collection methods are evaluated for their different efficiencies in contributing to national objectives., ********** Sustainably managed forests remove carbon from the atmosphere during their growth cycle, transferring that carbon by harvesting and processing to product carbon stores or fuels that displace fossil fuel-intensive [...]