Abstract
A key function of forest inventory is to detect changes in the area of forest land over time, yet different definitions of forest land are used in different regions of the world. Changes in the definition of forest intended to improve international consistency can affect the ability to quantify true changes over time. The objective of this study was to evaluate the effects of a definitional change from relative stocking to canopy cover on the area classified as forest land and its relationship to species and forest density in California, Oregon, and Washington. Both western Juniper and ponderosa pine will yield higher estimates of forest land area using a canopy cover definition in comparison to a stocking-based definition, with the difference being most pronounced where land is marginally forested. The change in definition may result in an additional 146,000 ha of forest land identified on the West Coast. Measuring marginal forest lands with both metrics for the first cycle after implementation should make it possible to distinguish real change from definitional change.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Andrews, H. J. (1932). Forest survey in the Douglas-fir region. Journal of Forestry, 30, 264–275.
Andrews, H. J., & Cowlin, R. W. (1940). Forest resources of the Douglas-fir region. Misc. Pub. 389. Portland: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 169 p.
Arner, S.L., Woudenberg, S., Waters, S., Vissage, J., MacLean, C., Thompson, & M. Hansen, M. (2001).National algorithm for determining stocking class, stand size class, and forest type for forest inventory and analysis plots. USDA Forest Service Northeastern Research Station Internal Rep., Newtown Square, PA, 10 p. http://www.fia.fs.fed.us/library/field-guides-methods-proc/docs/National%20algorithms.doc. Accessed 18 March 2013.
Bechtold, W. A. (2004). Largest crown-width prediction models for 53 species in the western United States. Western Journal of Applied Forestry, 19, 245–251.
Bechtold, W. A., & Patterson, P. L. (2004). The enhanced Forest Inventory and Analysis Program–national sampling design and estimation procedures (General Technical Report SRS-80). Asheville: USDA Forest Service, Southern Research Station.
Bunnell, F. L., & Vales, D. J. (1990). Comparison of methods for estimating forest overstory cover: differences among techniques. Canadian Journal of Forest Research, 20, 101–107.
Crookston, N. L., & Stage, A. R. (1999). Percent canopy cover and stand structure statistics from the forest vegetation simulator. General Technichal Report RMRS-GTR-24 (p. 11). Ogden: USDA Forest Service, Rocky Mountain Research Station.
Curtis, R. O. (1971). A tree area power function and related stand density measures for Douglas-fir. Forest Science, 7, 35–42.
Defries, R., & Eshleman, K. N. (2004). Land-use change and hydrologic processes: a major focus for the future. Hydrological Processes, 18, 2183–2186.
Fiala, A., Garman, S., & Gray, A. (2006). Comparison of five canopy-cover estimation techniques in the western Oregon Cascades. Forest Ecology Management, 232, 188–197.
Gillespie, A. J. R. (1999). Rationale for a national annual forest inventory program. Journal of Forestry, 97, 16–20.
Korhonen, I., Korhonen, K. T., Rautiainen, M., & Stenberg, P. (2006). Estimation of forest canopy cover: a comparison of field measurement techniques. Silva Fennica, 40(4), 577–588.
Lettman, G. J., Azuma, D. L., Herstrom, A. A., McKay, N., & Robinson, T. J. (2009). Forest, farms, and people: land use change on non-federal land in Oregon, 1974–2005. Salem: Oregon Department of Forestry. 74 p.
MacLean, C.D., & Bolsinger, C.L. (1973). Estimating productivity on sites with a low stocking capacity. U.S. Dept, Agric, Forest Service, Res. Pap. PNW-152, Portland, Oregon.
McArdle, R. E., Meyer, W. H., & Bruce, D. (1961). The yield of Douglas-fir in the Pacific Northwest. Technical Bulletin #201, revised. Washington: US Department of Agriculture. 65 p.
O’Brien, R. A. (1989). Comparison of overstory canopy cover estimates on forest survey plots. Research Paper INT-417. Ogden: USDA Forest Service, Intermountain Research Station. 5 p.
Reineke, L. H. (1933). Perfecting a stand-density index for even-aged forests. Journal of Agricultural Research, 46, 627–638.
Rudel, T. K., Coomes, O. T., Moran, E., Achard, F., Angelsen, A., Xu, J., et al. (2005). Forest transitions: towards a global understanding of land use change. Global Environmental Change, 15(2005), 23–31.
Theobald, D. M., Miller, R. J., & Hobbs, N. T. (1997). Estimating the cumulative effects of development on wildlife habitat. Landscape and Urban Planning, 39(1997), 25–36.
United Nations Food and Agriculture Program (2008). Guidelines for country reporting to FRA 2010. Forest Resources Assessment Programme, Working Paper 143, 80 pp. http://www.fao.org/forestry/14097-0a8d9580c21c82a81175207120544e2b8.pdf. Accessed 18 March 2013.
United Nations Food and Agriculture Program (2010). Global forest resources assessment, FRA 2010. Country Report, Vietnam 54 pp. http://www.fao.org/docrep/013/al664E/al664e.pdf. Accessed 18 March 2013.
USDA Forest Service (1996). Forest health monitoring 1996 field methods guide. Internal Rep. Research Triangle Park, NC: U.S. Department of Agriculture, Forest Service, National Forest Health Monitoring Program. 128 p.
USDA Forest Service. (2010). Forest Inventory and Analysis Program: field instructions for the annual inventory of Washington, Oregon, and California. Portland: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Azuma, D.L., Gray, A. Effects of changing forest land definitions on forest inventory on the West Coast, USA. Environ Monit Assess 186, 1001–1007 (2014). https://doi.org/10.1007/s10661-013-3434-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10661-013-3434-6