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Methods for Calculating Forest Ecosystem and Harvested Carbon with Standard Estimates for Forest Types of the United States

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Methods for Calculating Forest Ecosystem and Harvested Carbon with Standard Estimates for Forest Types of the United States United States Department of Methods for Calculating Forest Agriculture Forest Service Ecosystem and Harvested Carbon Northeastern with Standard Estimates for Research Station General Technical Forest Types of the United States Report NE-343 James E. Smith Linda S. Heath Kenneth E. Skog Richard A. Birdsey Abstract This study presents techniques for calculating average net annual additions to carbon in forests and in forest products. Forest ecosystem carbon yield tables, representing stand- level merchantable volume and carbon pools as a function of stand age, were developed for 51 forest types within 10 regions of the United States. Separate tables were developed for afforestation and reforestation. Because carbon continues to be sequestered in harvested wood, approaches to calculate carbon sequestered in harvested wood products are included. Although these calculations are simple and inexpensive to use, the uncertainty of results obtained by using representative average values may be high relative to other techniques that use site- or project-specific data. The estimates and methods in this report are consistent with guidelines being updated for the U.S. Voluntary Reporting of Greenhouse Gases Program and with guidelines developed by the Intergovernmental Panel on Climate Change. The CD- ROM included with this publication contains a complete set of tables in spreadsheet format. The Authors JAMES E. SMITH ([email protected]) is a research plant physiologist, USDA Forest Service, Northeastern Research Station, Durham, New Hampshire. LINDA S. HEATH ([email protected]) is a research forester/project leader, USDA Forest Service, Northeastern Research Station, Durham, New Hampshire. KENNETH E. SKOG ([email protected]) is a research forester/project leader, USDA Forest Service, Forest Products Laboratory, Madison, Wisconsin. RICHARD A. BIRDSEY ([email protected]) is a program manager, USDA Forest Service, Northeastern Research Station, Newtown Square, Pennsylvania. Cover Eric Fiegenbaum provided the cover artwork. Manuscript received for publication 21 December 2005 Published by: For additional copies: USDA FOREST SERVICE USDA Forest Service 11 CAMPUS BLVD SUITE 200 Publications Distribution NEWTOWN SQUARE PA 19073-3294 359 Main Road Delaware, OH 43015-8640 April 2006 Fax: (740)368-0152 Visit our homepage at: http://www.fs.fed.us/ne Methods for Calculating Forest Ecosystem and Harvested Carbon with Standard Estimates for Forest Types of the United States Contents Preface ..............................................................................................................................ii Introduction ......................................................................................................................1 Forest Ecosystem Carbon Tables ........................................................................................2 Table 1.—Defi nitions ....................................................................................................3 Table 2.—Example Yield Table ......................................................................................3 Tables for Harvested Wood Products Carbon ....................................................................5 Methods and Data Sources for Tables ................................................................................9 Table 3.—Example Harvest Scenario Table ...................................................................9 Uncertainty .....................................................................................................................17 Conclusions ....................................................................................................................18 Table 4.—Factors to Calculate Carbon in Growing-Stock Volume ..............................19 Table 5.—Factors to Estimate Carbon in Roundwood ................................................21 Table 6.—Disposition of Carbon in Industrial Roundwood ........................................22 Table 7.—Factors to Estimate Carbon in Primary Wood Products ..............................35 Table 8.—Fraction of Carbon in Primary Wood Products Remaining in End Uses .....36 Table 9.—Fraction of Carbon in Primary Wood Products Remaining in Landfi lls .......38 Table 10.—Confi dence Intervals for Carbon in Trees ..................................................40 Acknowledgments ...........................................................................................................44 Literature Cited ...............................................................................................................44 Appendix A: Yield Tables for Reforestation ......................................................................47 Appendix B: Yield Tables for Afforestation (Establishment on Nonforest Land) ..............99 Appendix C: Scenarios of Carbon in Forests and Harvested Wood Products .................151 Appendix D: Details on Development and Use of Tables ..............................................193 Preface In 2002, President George W. Bush directed the Department of Energy and the Department of Agriculture to revise the system for reporting and registering reductions in greenhouse gas emissions. Increasing carbon sequestration by forests and harvested products is equivalent to reducing emissions, and represents a signifi cant opportunity for the private sector to voluntarily take action. Rules and guidelines are needed to provide a basis for consistent estimation of the quantity of carbon sequestered and emissions reduced by forestry activities, and can be used to determine the value of tradable credits. The value of registered carbon credits can provide increased income for landowners, support rural development, and facilitate sustainable forest management. Many prospective reporting entities require information and decision-support software to evaluate prospects and develop plans for implementing forestry activities, and to estimate rates of carbon sequestration for reporting purposes. Estimating the quantity of carbon sequestered could be a diffi cult and expensive task, possibly requiring the establishment of a monitoring system based on remote sensing, fi eld measurements, and models. However, there are situations for which a simpler estimation process is acceptable, requiring only a basic familiarity with defi nitions and accounting rules. In practice, reporters may choose the simplest available methods that provide estimates with a degree of accuracy that meets reporting objectives. The information provided in this publication can be used to estimate carbon emissions, emission reductions, or sequestration about a forestry activity—data on the forest area affected, type of activity, and region of interest. The quality of the results will depend largely on the quality of the activity data and how closely actual activities are refl ected in the factors. The intent in providing this information is to provide consistent and reliable estimates and to simplify the reporting process. The tables in this publication represent signifi cant updates of similar tables used for more than a decade to analyze forest carbon sequestration activities (Birdsey 1996). Since the previous tables were published, advances have been made in methods that estimate how various carbon components of forest ecosystems change over time, and how carbon in harvested products is retained in use or emitted to the atmosphere. This publication further documents the General Guidelines for reporting greenhouse gas infor ma tion under Section 1605(b) of the Energy Policy Act of 1992. Richard A. Birdsey Richard A. Birdsey Northern Global Change Program Manager Forest Service 1605(b) Team Leader U.S. Department of Agriculture Introduction carbon and timber projection models, and a more precise International agreements recognize forestry activities defi nition of carbon pools. We also include additional as one way to sequester carbon, and thus mitigate the forest types and background information for customizing increase of carbon dioxide in the atmosphere; this may the tables for a user’s specifi c needs. slow possible climate change effects. The United States initiated a voluntary reporting program in the early The look-up tables are categorized by region, forest 1990’s (U.S. Dep. Energy 2005). A system for developing type, previous land use, and, in some cases, productivity estimates of the quantity of carbon sequestered in forest class and management intensity. Users must identify stands and harvested wood products1 throughout the the categories for their forest, estimate the area of United States is a vital part of the voluntary program. forestland, and, if needed, characterize the amount of This system must be relatively easy to use, transparent, wood harvested from the area in a way that is compatible economical, and accurate. In this publication, we present with the format of the look-up tables. The average methods and regional average tables that meet these carbon estimates per area in the look-up tables must criteria. be multiplied by the area or, as appropriate, harvested volumes, to obtain estimates in total carbon stock or Carbon is sequestered in growing trees, principally change in carbon stock. as wood in the tree bole. However, accrual in forest ecosystems also depends on the accumulation of carbon The estimates in the look-up tables are called “average in dead wood, litter, and soil organic matter. When wood estimates,” indicating that they should be used when it is harvested and removed
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