Diameter versus girthwhich variable provides the best estimate of the cross-sectional area?

  1. Rodríguez, Francisco
  2. Blanco, Ricardo
  3. Aunós, Álvaro
Journal:
Forest systems

ISSN: 2171-5068

Year of publication: 2015

Volume: 24

Issue: 3

Type: Article

DOI: 10.5424/FS/2015243-05945 DIALNET GOOGLE SCHOLAR lock_openDialnet editor

More publications in: Forest systems

Sustainable development goals

Abstract

Aim of study: Cross-sectional area is one of the most important forest inventory variable since it is highly correlated with growth and yield at both tree and stand levels. In this research, we evaluated the bias, precision and accuracy of three measurements such as cross-sectional area: the girth, the arithmetic mean diameter, and the geometric mean diameter normally used to estimate the cross-sectional area in practical forestry.Area of study: Measurements were taken in a poplar plantation (Populus x euramericana (Dode) Guinier cv. Luisa Avanzo) located in Huesca, Spain.Material and Methods: A total of 5,408 cross-sectional areas from 48 poplar trees were measured with and image based software. To test the differences between real and estimated cross-sectional area based on the three measurements of study, a multilevel mixed-effect model was used.Main Results: All three measurements overestimated the cross-sectional area by (0.47%-2.37%) and were found to be biased. Estimations based on arithmetic or geometric mean diameter of the maximum and minimum axes were more accurate than those using tree girth.Research highlights: There was a strong correlation between estimation errors and departures from a circumference in the cross section i.e. estimation errors were larger in elliptical cross-sections than in those closer to a circumference. In order to avoid overestimation of growth and yield derived from cross-sectional area estimates, we recommend using the geometric mean diameter trying to measure the largest and the smallest diameters of the section, especially on trees that are clearly elliptical.Keywords: diameter; circumference; cross-sectional area; poplar plantations.

Bibliographic References

  • References
  • Avery TE, Burkhart HE, 1994. Forest measurements. Ed. 4. McGrawHill, New York. 408 pp.
  • Ball J, Carle J, Del Lungo A, 2005. Contribution of poplars and willows to sustainable forestry and rural development. Unasylva, 221(56): 3-9.
  • Barack C, 2001. Forest Measurement and Modeling - Measuring trees, stands and forests for effective forest management. Computer-based course resources for Forest Measurement and Modeling (FSTY2009) at the Australian National University Available in http://fennerschool-associated.anu.edu.au/mensuration/index.htm [2 March 2014].
  • Biging GS, Wensel LC, 1988. The Effect of Eccentricity on the Estimation of Basal Area and Basal Area Increment of Coniferous Trees. Forest Science 34(3): 621-633.
  • Brickell JE, 1970. More on diameter tape and calipers. J For 68(3): 169–170.
  • Cauchy AL, 1841. Mémoire sur les dilatations, les condensations et les rotations produits par un changement de forme dans un système de points matériels. Oeuvres (2)12: 343-377.
  • Chacko VJ, 1961. A study of the shape of cross-section of stems and the accuracy of caliper measurement. Indian For 87: 758-762.
  • DeBell JD, Gartner BL, DeBell DS, 1998. Fiber length in young hybrid Populus stems grown at extremely different rates. Can J For Res 28: 603-608. http://dx.doi.org/10.1139/x98-031
  • García O, 1995. Apuntes de mensura forestal I: Estática. Universidad Austral de Chile. Facultad de Ciencias Forestales. 65 pp.
  • Kellogg RM, Barber FJ, 1981. Stem eccentricity in coastal western hemlock. Can J For Res 11: 714-718. http://dx.doi.org/10.1139/x81-099
  • Mackie ED, Matthews RW. 2006. Forest Mensuration, a handbook for practitioners. HMSO, Edinburgh. 330 pp.
  • Matérn B, 1990. On the shape of the cross-section of a tree stem: An empirical study of the geometry of mensuration methods. Swedish Univ. of Agric., Section of For. Biometry. Umeå, Sweden. 47 pp.
  • McCulloch CE, Searle SR, 2001. Generalized, Linear and Mixed Models. Wiley series in probability and statistics, New York. 321 pp.
  • Meiresonne L, Nadezhdin N, Cermak J, Van Slycken J, Ceulemans R, 1999. Measured sap flow and simulated transpiration from a poplar stand in Flanders (Belgium). Agr Forest Meteorol 96: 165-179. http://dx.doi.org/10.1016/S0168-1923(99)00066-0
  • Monserud RA, 1979. Relations between inside and outside bark diameter at breast height for Douglas-fir in northern Idaho and northwestern Montana. USDA For Serv INT-266. 8 pp. http://dx.doi.org/10.5962/bhl.title.79427
  • Roda JM, 2001. Form function for the `I-214' poplar merchantable stem (Populus euramericana (Dode) Guinier cv cultivar `I-214'). Ann For Sci 58(1): 77- 87. http://dx.doi.org/10.1051/forest:2001108
  • Rodríguez F, Pemán J, Aunós A, 2010. A reduced growth model based on stand basal area. A case for hybrid poplar plantations in northeast Spain. For Eco Man 259: 2093-2102.
  • Rodríguez F, 2005. Modelos de producción de las choperas del valle del Cinca. Tesis doctoral, Universitat de Lleida.
  • Saint-André L, Leban JM, 2000. An elliptical model for tree ring shape in transverse section. Methodology and case study on Norway Spruce. Holz Roh und Werkst (58): 368-374. http://dx.doi.org/10.1007/s001070050447
  • Schabenberger O, Pierce FJ, 2002. Contemporary Statistical Models for the Plant and Soil Sciences. CRC Press, Boca Raton. 738 pp.
  • Steenackers J, Steenackers V, Van Acker J, Stevens M, 1993. Stem form, volume and dry matter production in a twelve-year-old circular Nelder plantation of Populus trichocarpa × deltoides 'Beaupré'. Forestry Chronicle, 69(6): 730-735. http://dx.doi.org/10.5558/tfc69730-6
  • Williamson RL, 1975. Out-of roundness of Douglas-fir stems. For Sci 21(4): 365-370.