Abstract
In this paper, critical length sampling for estimating the volume of downed coarse woody debris is presented. Using this method, the volume of downed wood in a stand can be estimated by summing the critical lengths of down logs included in a sample obtained using a relascope or wedge prism; typically, the instrument should be tilted 90° from its usual orientation in sampling live trees. The critical length of a downed tree is the length of the log section large enough in diameter to be counted from the selected sample point. A simulation study was conducted to compare critical length sampling with diameter relascope sampling and perpendicular distance sampling. For the population studied, diameter relascope sampling tended to have the smallest variance but exhibited a small design-bias. By combining critical length sampling with critical height sampling—a method previously described for estimating the volume of standing trees—the total volume of dead wood in a stand can be estimated using the same basic principle. One use of the combined method might be in rapid in-place inventories where a quick estimate of the volume of dead wood is needed for biodiversity management purposes. The combined critical length/height method provides a relatively simple means for obtaining such estimates.
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Notes
With this approach, instead of applying Monte-Carlo sampling simulation (which is the typical sampling simulation approach), numerical integration was applied to calculate the first and second moments.
References
Affleck DLR (2008) A line intersect distance sampling strategy for down wood inventory. Can J For Res 38:2262–2273
Bebber DP, Thomas SC (2003) Prism sweeps for coarse woody debris. Can J For Res 33:1737–1743
Bitterlich W (1984) The relascope idea. Commonwealth Agricultural Bureaux, London
Bruce D (1955) A new way to look at trees. J For 53:163–167
Fraver S, Ringvall A, Jonsson B-G (2007) Refining volume estimates of down woody debris. Can J For Res 37:627–633
Gove JH, Ringvall A, Ståhl G, Ducey MJ (1999) Point relascope sampling of downed coarse woody debris. Can J For Res 29:1718–1726
Gove JH, Williams MS, Ståhl G, Ducey MJ (2005) Critical point relascope sampling for unbiased volume estimation of downed coarse woody debris. Forestry 78:417–431
Grosenbaugh LR (1963) Optical dendrometers for out-of-reach diameters: a conspectus and some new theory. Forest Science Monograph 4:47
Iles K (1979) Systems for selecting truly random samples from tree populations and the extension of variable plot sampling to the third dimension. PhD dissertation, University of British Columbia, Vancouver, Canada. 144 pp
Iles K (1990) Critical height sampling: a workshop on the current state of the technique. In Proceedings of the IUFRO symposium: state-of-the-art methodology of forest inventory. August, 1989. Syracuse, NY. USDA For. Serv Gen Tech Rep. PNW-GTR-263
Kalliovirta J, Laasasenaho J, Kangas A (2005) Evaluation of the laser-relascope. For Ecol Manag 204:181–194
Kitamura M (1962) On an estimate of the volume of trees in a stand by the sum of critical heights (in Japanese). Kai Nichi Rin Ko 73:64–67
Samuelsson J, Gustafsson L, Ingelög T (1994). Dying and dead trees, a review of their importance for biodiversity. Swedish Environmental Protection Agency, Report 4306
Schreuder HT, Gregoire TG, Wood GB (1993) Sampling methods for multiresource forest inventory. Wiley, New York
Ståhl G (1998) Transect relascope sampling. A method for the quantification of coarse woody debris. For Sci 44:58–63
Thompson SK (1992) Sampling. Wiley, New York
Valentine HT, Gove JH, Ducey MJ, Gregoire TG, Williams MS (2008) Estimating the carbon in coarse woody debris with perpendicular distance sampling. In: Hoover CM (ed) Field measurements for forest carbon monitoring. Springer, Berlin, pp 73–87
Warren WG, Olsen PF (1964) A line intersect technique for assessing logging waste. For Sci 10:267–276
Wikström P, Eriksson LO (2000) Solving the stand management problem under biodiversity-related considerations. For Ecol Manag 126:361–376
Williams MS (2001) New approach to areal sampling in ecological surveys. For Ecol Manag 154:11–22
Williams MS, Gove JH (2003) Perpendicular distance sampling: another method of sampling coarse woody debris. Can J For Res 33:1564–1579
Williams MS, Ducey MJ, Gove JH (2005a) Assessing surface area of coarse woody debris with line intersect and perpendicular distance sampling. Can J For Res 35:949–960
Williams MS, Gove JH, Valentine HT, Ducey MJ (2005b) Additional results for perpendicular distance sampling. Can J For Res 35:961–966
Acknowledgments
Mary Dellenbaugh provided valuable editorial comments. The project was supported by the National Research Initiative of the USDA Cooperative State. Research, Education and Extension Service, grant number 2003-35101-13646.
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Communicated by J. Müller.
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Ståhl, G., Gove, J.H., Williams, M.S. et al. Critical length sampling: a method to estimate the volume of downed coarse woody debris. Eur J Forest Res 129, 993–1000 (2010). https://doi.org/10.1007/s10342-010-0382-3
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DOI: https://doi.org/10.1007/s10342-010-0382-3