The Tongass National Forest (Tongass) is the largest national forest and largest area of old-growth forest in the United States. Spatial geographic information system data for the Tongass were combined with forest inventory data to estimate and map total carbon stock in the Tongass; the result was 2.8 ± 0.5 Pg C, or 8% of the total carbon in the forests of the conterminous USA and 0.25% of the carbon in global forest vegetation and soils. Cumulative net carbon loss from the Tongass due to management of the forest for the period 1900–95 was estimated at 6.4–17.2 Tg C. Using our spatially explicit data for carbon stock and net flux, we modeled the potential effect of five management regimes on future net carbon flux. Estimates of net carbon flux were sensitive to projections of the rate of carbon accumulation in second-growth forests and to the amount of carbon left in standing biomass after harvest. Projections of net carbon flux in the Tongass range from 0.33 Tg C annual sequestration to 2.3 Tg C annual emission for the period 1995–2095. For the period 1995–2195, net flux estimates range from 0.19 Tg C annual sequestration to 1.6 Tg C annual emission. If all timber harvesting in the Tongass were halted from 1995 to 2095, the economic value of the net carbon sequestered during the 100-year hiatus, assuming $20/Mg C, would be $4 to $7 million/y (1995 US dollars). If a prohibition on logging were extended to 2195, the annual economic value of the carbon sequestered would be largely unaffected ($3 to $6 million/y). The potential annual economic value of carbon sequestration with management maximizing carbon storage in the Tongass is comparable to revenue from annual timber sales historically authorized for the forest.
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Alemdag IS. 1984. Total tree and merchantable stem biomass equations for Ontario hardwoods. Informational Report PI-X-46. Canadian Forestry Service. Canada Chalk River, Ontario: Petawawa National Forestry Institute, Canadian Forestry Service, Agriculture
Alexander EB, Kissinger E, Huecker RH, Cullen P. 1989. Soils of southeast Alaska as sinks for organic carbon fixed from atmospheric carbon-dioxide. p. 203-210 In E.B. Alexander (ed.) Proc. of Watershed ’89: A conference on the Stewardship of Soil, Air, and Water Resources. 21-23 Mar. 1989. Juneau, Alaska. USDA Forest Service General Technical Report No. R10-MB-77. Juneau, Alaska: USDA Forest Service
Barker JR, Baumgardner GA, Turner DP, Lee JJ. 1995. Potential carbon benefits of the Conservation Reserve Program in the United States. J Biogeogr 22:743–51
Brown JK. 1974. Handbook for inventorying downed woody material. General Technical Report INT-GTR-16. US Department of Agriculture. Intermountain Forest and Range Experiment Station Fort Collins, Colorado
Cairns MA, Brown S, Helmer EH, Baumgardner GA. 1997. Root biomass allocation in the world’s upland forests. Oecologia 111:1–11
Caspersen JP, Pacala SW, Jenkins JC, Hurtt GC, Moorcraft PR, Birdsey RA. 2000. Contributions of land-use history to carbon accumulation in U.S. forests. Science 290:1148–51
D’Amore DV, Lynn WC. 2002. Classification of forested Histosols in southeast Alaska. Soil Sci Soc Am J 66:554–62
DeMars DJ. 2000. Stand-density study of spruce-hemlock stands in southeastern Alaska. General Technical Report PNW-GTR-496. US Department of Agriculture. Ogden, Utah: Pacific Northwest Research Station
Dixon RK, Brown S, Houghton RA, Solomon AM, Trexler MC, Wisniewski J. 1994. Carbon pools and flux of global forest ecosystems. Science 263:185
Everest FH, Swanston DN, Shaw CG III, Smith WP, Julin KR, Allen SD. 1997. Evaluation of the use of scientific information in developing the 1997 forest plan for the Tongass National Forest. General Technical Report PNW-GTR-415. US Department of Agriculture Forest Service. Portland, Oregon: Pacific Northwest Research Station
Fahey TD. 1983. Product recovery from hemlock “pulpwood” from Alaska. Research Paper PNW-303. US Department of Agriculture. Portland, Oregon: Pacific Northwest Forest and Range Experiment Station
Hamburg SP, Zamolodchikov DG, Korovin GN, Nefedjev VV, Utkin AI, Gulbe JI, Gulbe TA. 1997. Estimating the carbon content of Russian forests: a comparison of phytomass/volume and allometric projections. Mitigation and Adaptation Strategies for Global Change Netherlands: Springer2:247–65
Harmon ME, Ferrell WK, Franklin JF. 1990. Effects on carbon storage of conversion of old-growth forests to young forests. Science 247:699–702
Houghton RA, Hackler JL, Lawrence KT. 1999. The U.S. carbon budget: contributions from land-use change. Science 285:574–7
Janisch JE, Harmon ME. 2002. Successional changes in live and dead wood carbon stores: implications for net ecosystem productivity. Tree Physiol 22:77–89
Johnson DW, Curtis PS. 2001. Effects of forest management on soil C and N storage: meta-analysis. For Ecol Manage 140:227–38
Kimmey JW. 1956. Cull factors for Sitka spruce, western hemlock and western red cedar in southeast Alaska. Station Paper No. 6. US Department of Agriculture. Juneau, Alaska: Alaska Forest Research Center
Krumlik GJ. 1974. Biomass and nutrient distribution in two old growth forest ecosystems in south coastal British Columbia. Masters thesis, University of British Columbia, Vancouver, B.C
Nowacki G, Shephard M, Krosse P, Pawuk W, Fisher G, Baichtal J, Brew D, and others. 2001. Ecological subsections of southeast Alaska and neighboring areas of Canada. Technical Publication R10-TP-75. US Department of Agriculture Forest Service. Alaska Region, Juneau, Alaska: USDA Forest Service
Prentice IC, Farquhar GD, Fasham MJR, Goulden ML, Heimann M, Jaramillo VJ, Kheshgi HS, et al. 2001. The carbon cycle and atmospheric carbon dioxide. In: Houghton JT, Ding Y, Griggs DJ, Noguer M, van der Linden PJ, Dai X, Maskell K, et al, editors. Climate change 2001: the scientific basis. Cambridge (UK): Cambridge University Press. p 183–238
Sampson RN, Hair D, editors. 1996. Forest management opportunities for mitigating carbon emissions. Forest and global change; vol 2. American Forests Washington, D.C.
Santantonio D, Hermann RK, Overton WS. 1977. Root biomass studies in forest ecosystems. Pedobiologia 17:1–31
Shaw DL. 1977. Biomas equations for Douglas-fir, western redcedar, and red alder in Washington and Oregon. Tech. Rep. 044-3001/77/22. Centralia, WA: Weyerhaeuser Corp
Singh T. 1983. Weight tables for important tree species in the Northwest Territories. Report on. NOR FMN-27. Canadian Forestry Service. Edmonton, Alberta: Northern Forest Research Centre
Skog KE, Nicholson GA. 1998. Carbon cycling through wood products: the role of wood and paper products in carbon sequestration. For Prod J 48(7):75–84
Smithwick EAH, Harmon ME, Remillard SM, Acker SA, Franklin JF. 2002. Potential upper bounds of carbon stores in forests of the pacific northwest. Ecol Appl 12(5):1303–17
Standish JT, Manning GH, Demaerschalk JP. 1983. Development of biomass equations for British Columbia tree species. Informational Report BC-X-264. Canadian Forestry Service. Victoria, B.C.: Pacific Forest Research Centre
Turner DP, Koerper GJ, Harmon ME, Lee JJ. 1995. A carbon budget for forests of the conterminous United States. Ecol Appl 5(2):421–36
US Forest Products Laboratory. 1974. Wood handbook: wood as an engineering material. Agricultural Handbook 72. US Department of Agriculture. Washington, D.C.: US Government Printing Office
USDA Forest Service. 2005. Tongass National Forest facts. Available online at: http://www.fs.fed.us/r10/tongass/
USDA Forest Service. 2000. Tongass National Forest. Available online at: Existing_Veg [vector digital data]. http://www.permanent.access.gpo.gov/websites/fsfedus/www.fs.fed.us/r10/tongass/gisinfo/page
USDA Forest Service. 2001. Timber Sale Program Information Reporting System (TSPIRS), fiscal year 1998 TSPIRS documents. Available online at: http://www.fs.fed.us/land/fm/tspirs/1998tspirs/
USDA Forest Service. 1995a. Timber supply and demand. Alaska National Interest Lands Conservation Act. Section 706(a). Report to Congress no. 15. Alaska National Interest Lands Conservation Act, Sect. 706(a) Report to Congress. Alaska Region, Juneau, Alaska: US Forest Service
USDA Forest Service. 1995b. Field procedures for the southeast Alaska inventory 1995. Juneau, Alaska: Pacific Northwest Research Station Forestry Sciences Laboratory and Region 10
USDA Soil Conservation Service. 1992a. Classification and correlation of the soils of the Stikine area, Alaska. Report no. SSSA-645. US Department of Agriculture. Petersburg Area, Anchorage, Alaska: USDA Forest Service
USDA Soil Conservation Service. 1992b. Classification and correlation of the soils of the Chatham area, Alaska. Report no. SSSA-646. US Department of Agriculture. Sitka Area, Anchorage, Alaska: USDA Forest Service
USDA Soil Conservation Service. 1994. Classification and correlation of the soils of the Ketchikan area, Alaska. Report no. SSSA-644. US Department of Agriculture. Ketchikan Area, Anchorage, Alaska: USDA Forest Service
US Environmental Protection Agency. 2003. Inventory of U.S. greenhouse gas emissions and sinks: 1990–2001. Washington (DC): US Environmental Protection Agency
Waddel KL. Public Communication 2001. An application of line interest sampling to estimate attributes of coarse woody debris in resource inventories, USDA Forest Service Pacific Northwest research Station, Forest Sciences Laboratory, Portland, Oregon
Warren DD. 1999. Production, prices, employment, and trade in northwest forest industries, fourth quarter 1997. Resource Bulletin PNW-RB-230. US Department of Agriculture. Portland, Oregon: Pacific Northwest Research Station
Watson RT, Noble IR, Bolin B, Ravindranath NH, Verardo DJ, Dokken DJ, editors. 2000. Land use, land-use change, and forestry. Cambridge (UK): Cambridge University Press
Weyant JP. 2000. An introduction to the economics of climate change policy. Arlington (VA): Pew Center on Global Climate Change. 56 p
Yanai RD, Currie WS, Goodale CL. 2003. Soil carbon dynamics following forest harvest: an ecosystem paradigm reviewed. Ecosystems 6:197–212
Yarie J, Mead BR. 1988. Twig and foliar biomass estimation equations for major plant species in the Tanana River basin of interior Alaska. Research Paper PNW-RP-401. US Department of Agriculture. Portland, Oregon: Pacific Northwest Research Station
W.W.L. received financial support from the Royce Fellowship program at Brown University. We thank Mike McClellan, Frances Biles, and Dave D’Amore at the US Forest Service Juneau Forestry Sciences Laboratory for invaluable help with data collection and manipulation. Mark Harmon, Linda Heath, and two anonymous reviewers provided insightful comments on an earlier version of the manuscript.
APPENDIX 1. DATA COLLECTION PROTOCOL USDA FOREST SERVICE 1995 FOREST INVENTORY ASSESSMENT (FIA) SOUTHEAST ALASKA GRID INVENTORY
USDA Forest Service personnel used global positioning system (GPS) units to locate the center point of each sampling plot and three additional points 36.6 m from the central point at azimuths of 360°, 120°, and 240°.
Trees more than 12.5 cm in diameter at breast height (dbh) were recorded at all four points in 14.6-m–diameter subplots.
Trees/saplings/seedlings less than 12.5 cm dbh were recorded at all four points in 4-m–diameter subplots.
Main Vegetation Types (MVT) were defined based on a combination of species cover and stature at all four points using the 14.6-m–diameter subplots.
Horizontal/vertical (HV) profiles of understory vegetation were used to estimate percent cover in two 11.3-m–diameter subplots within each MVT identified at the sampling location.
Three 11.3-m downed-wood transects intersecting at the center with azimuths of 360°, 120°, and 240° were constructed in each HV subplot.
One soil pit (no more than 50 cm deep) was dug at a representative location within each plot.
APPENDIX 4. CALCULATION OF CARBON STOCKS IN SMALL WOODY DEBRIS (SWD) AND COARSE WOODY DEBRIS (CWD)
The cubic volume (m3) of each piece of CWD was calculated as:
where D S is the small-end diameter (cm), D L is the large-end diameter (cm), and l is the length of the piece of CWD (m). The volume for each piece of CWD was then converted to an areal value (m3/ha) using the following equation:
where L is the total length of the transect line in the plot (m). Finally, the oven-dried biomass (kg/ha) for each piece of CWD was calculated as:
where SpG is the specific gravity of the debris piece (varies by species, unitless), and DCR is the decay class reduction factor, calculated as 1−% decay (recorded to the nearest 5% in Forest Inventory Assessment [FIA] data), and expressed as a decimal. The mass per unit area was summed for all CWD recorded in the FIA data and multiplied by 0.5 to calculate the total carbon stock.
As an example of the methods used to calculate carbon stocks in SWD: Total carbon stock (kg/ ha) in Pacific silver fir SWD was calculated as:
where freq is the total number of intersections with Pacific silver fir SWD recorded in the FIA data, slp is the sum of slope estimates (% slope) for all the records of Pacific silver fir SWD in the FIA data, and decay is the sum of decay estimates (amount of rotten or otherwise missing wood, recorded as a percent) for all records of Pacific silver fir SWD in the FIA data. The quantity (slp/freq) is an estimate of the average slope at the FIA sample point, and the quantity (decay/freq) is an estimate of the average amount of decay in Pacific silver fir SWD at the FIA sample point. The non-slash, non-horizontal correction factor and “composite” species composition factors described by Brown (1974) were used to develop species-specific equations. The specific gravity of hardwood SWD lacking species identification was assumed to be 0.363, the numerical average of all hardwood species found in southeast Alaska (US Forest Products Laboratory 1974). Estimates of carbon stocks in SWD calculated with species-specific equations, like the one described above, were summed across all species to estimate total carbon stock (kg/ha) in SWD at each FIA sample point.
APPENDIX 6. RELATIONSHIP BETWEEN ABOVEGROUND AND SOIL CARBON STOCKS CORRESPONDING TO ECOSYSTEM TYPES IN THE TONGASS
Plotting soil carbon stock against aboveground carbon stock for each Aboveground Carbon Polygon Type (ACPT) shows a relationship between aboveground and soil carbon stocks that reflects general ecosystem characteristics. High soil carbon stocks in muskeg and deep saprist soils correlate with moderate to low aboveground carbon stocks (filled circles). A wide range in aboveground carbon stocks is supported by a well-defined range of soil carbon stock (filled triangles). Indicating the influence of other factors on aboveground carbon stocks. Rocky, icy, and otherwise harsh locations (filled squares) have little soil or aboveground carbon. ACPT 8 is an outlier (open diamond).
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Leighty, W.W., Hamburg, S.P. & Caouette, J. Effects of Management on Carbon Sequestration in Forest Biomass in Southeast Alaska. Ecosystems 9, 1051–1065 (2006). https://doi.org/10.1007/s10021-005-0028-3
- carbon sequestration
- geographic information system
- climate change
- forest management