Effects of adding crown variables in stem taper and volume predictions for black pine

Crown characteristics are an important component of growth and yield models. The stem form of a tree depends to a large extent on the tree crown dimensions. However, there is no unified agreement on whether crown variables (crown ratio and crown length) should be incorporated into taper models for accurate predictions of diameter and volume. The purpose of this study was to investigate the level of improvement that the incorporation of crown variables into taper equations for black pine (Pinus nigra J.F.Arnold subsp. pallasiana (Lamb.) Holmboe) gives to diameter and stem volume predictions. Linear and nonlinear crown variable functions were incorporated into a compatible volume and taper equation to evaluate their effect in model prediction accuracy. The inclusion of crown variables provided significantly different parameter estimates but only resulted in a modest reduction of fitting statistics for both diameter and volume with lower average bias and lower mean squared errors for all modified models, although the improvement in stem volume prediction was minimal. Based on the results, the improvement obtained by the inclusion of crown variables is not enough to justify the additional costs in measuring crown variables of standing trees for volume estimation.

Effects of adding crown variables in stem taper and volume predictions for black pine

Crown characteristics are an important component of growth and yield models. The stem form of a tree depends to a large extent on the tree crown dimensions. However, there is no unified agreement on whether crown variables (crown ratio and crown length) should be incorporated into taper models for accurate predictions of diameter and volume. The purpose of this study was to investigate the level of improvement that the incorporation of crown variables into taper equations for black pine (Pinus nigra J.F.Arnold subsp. pallasiana (Lamb.) Holmboe) gives to diameter and stem volume predictions. Linear and nonlinear crown variable functions were incorporated into a compatible volume and taper equation to evaluate their effect in model prediction accuracy. The inclusion of crown variables provided significantly different parameter estimates but only resulted in a modest reduction of fitting statistics for both diameter and volume with lower average bias and lower mean squared errors for all modified models, although the improvement in stem volume prediction was minimal. Based on the results, the improvement obtained by the inclusion of crown variables is not enough to justify the additional costs in measuring crown variables of standing trees for volume estimation.

___

  • Bailey RL (1995) Upper stem volumes from stem analysis data: an overlapping bolts method. Can J For Res 25: 170–173.
  • Baldwin VC Jr, Polmer BH (1981) Taper functions for unthinned longleaf pine plantations on cutover West Gulf sites. In: Proceedings of the 1st Biennial Southern Silviculture Research Conference (Ed. JP Barnett). USDA Forest Service, New Orleans, pp. 156–163.
  • Bates DM, Watts DG (1988) Nonlinear Regression Analysis and Its Applications. Wiley, New York.
  • Bi H (2000) Trigonometric variable-form taper equations for Australian eucalyptus. For Sci 46: 397–409.
  • Burkhart HE, Walton SB (1985) Incorporating crown ratio into taper equations for loblolly pine trees. For Sci 31: 478–484.
  • Calama R, Montero G (2006) Stand and tree-level variability on stem form and tree volume in Pinus pinea L.: a multilevel random components approach. Sist Recur For 15: 24–41.
  • Clark A 3rd, Souter RA, Schlaegel BE (1991) Stem profile equations for Southern tree species. USDA Forest Service, New Orleans, Res. Pap. SE-282.
  • Fang Z, Borders BE, Bailey RL (2000) Compatible volume taper models for loblolly and slash pine based on system with segmented-stem form factors. For Sci 46: 1–12.
  • Farrar RM (1987) Stem-profile functions for predicting multipleproduct volumes in natural longleaf pines. South J Appl For 11: 161–167.
  • Farrar RM, Murphy PA (1987) Taper functions for predicting product volumes in natural shortleaf pines. USDA Forest Service, New Orleans, Res. Pap. SO-234.
  • Hann DW, Walters DK, Scrivani JA (1987) Incorporating crown ratio into prediction equations for Douglas-fir stem volume. Can J For Res 17: 17–22.
  • Jiang L, Brooks JR, Hobbs GR (2007) Using crown ratio in yellowpoplar compatible taper and volume equations. North J Appl For 24: 271–275.
  • Jiang L, Brooks JR, Wang J (2005) Compatible taper and volume equations for yellow-poplar in West Virginia. For Ecol Manage 213: 399–409.
  • Jiang L, Liu R (2011) Segmented taper equations with crown ratio and stand density for Dahurian Larch (Larix gmelinii) in Northeastern China. J For Res 22: 347–352.
  • Kozak A (1997) Effects of multicollinearity and autocorrelation on the variable-exponent taper functions. Can J For Res 27: 619– 6
  • Kozak A, Munro DD, Smith, JHG (1969) Taper functions and their application in forest inventory. For Chron. 45: 278–283.
  • Kozak A, Smith JHG (1993) Standards for evaluating taper estimating systems. For Chron 69: 438–444.
  • Larson PR (1963) Stem form development of forest trees. For Sci Monograph 5.
  • Lee WK, Seo JH, Son YM, Lee KH, von Gadow K (2003) Modeling stem profiles for Pinus densiflora in Korea. For Ecol Manage 172: 69–77.
  • Leites LP, Robinson AP (2004) Improving taper equations of loblolly pine with crown dimensions in mixed-effects modeling framework. For Sci 50: 204–212.
  • Li R, Weiskittel AR (2010) Comparison of model forms for estimating stem taper and volume in the primary conifer species of the North American Acadian Region. Ann For Sci 67: 302–317.
  • Mäkelä A (2002) Derivation of stem taper from the pipe theory in a carbon balance framework. Tree Physiol 22: 891–905.
  • Max TA, Burkhart HE (1976) Segmented polynomial regression applied to taper equations. For Sci 22: 283–289.
  • Matney TG, Sullivan AD (1979) Absolute form quotient taper curves and their application to old-field plantation loblolly pine trees. In: Forest Resource Inventories, Workshop Proceedings, Vol. II (Ed. WE Frayer). Colorado State University, Fort Collins, CO, USA, pp. 831–842.
  • Muhairwe CK (1994) Tree form and taper variation over time for interior lodgepole pine. Can J For Res 24: 1904–1913.
  • Muhairwe CK, LeMay VM, Kozak A (1994) Effects of adding tree, stand, and site variables to Kozak’s variable-exponent taper equation. Can J For Res 24: 252–259.
  • Neter J, Kutner MH, Nachtsheim CJ, Wasserman W (1996) Applied Linear Statistical Models. Times Mirror Higher Education Group, Chicago.
  • Özçelik R, Brooks JR (2012) Compatible volume and taper models for economically important tree species of Turkey. Ann For Sci 69: 105–118.
  • SAS Institute Inc. (2002) SAS/ETS User’s Guide, Version 9.0. SAS Institute, Inc., Cary, NC, USA.
  • Shaw DJ, Meldahl RS, Kush JS, Somers GL (2003) A tree taper model based on similar triangles and use of crown ratio as a measure of form in taper equations for longleaf pine. USDA Forest Service Gen. Tech. Rep. SRS-66, Asheville, NC, USA.
  • Trincado G, Burkhart HE (2006) A generalized approach for modeling and localizing stem profile curves. For Sci 52: 670– 6
  • Valenti MA, Cao QV (1986) Use of crown ratio to improve loblolly pine taper equations. Can J For Res 16: 1141–1145.
  • Valentine HT, Gregoire TG (2001) A switch model of bole taper. Can J For Res 31: 1400–1409.
  • Weiskittel AR, Hann DW, Kershaw JA, Vanclay JK (2011) Forest growth and yield modeling. Wiley & Blackwell, London.
  • Williams MS, Reich RM (1997) Exploring the error structure of taper equations. For Sci 43: 378–386.
Turkish Journal of Agriculture and Forestry-Cover
  • ISSN: 1300-011X
  • Yayın Aralığı: Yılda 6 Sayı
  • Yayıncı: TÜBİTAK
Sayıdaki Diğer Makaleler

The effect of tillage systems on yield and quality of durum wheat cultivars

Andrzej WOZNIAK

The effects of heartwood and sapwood on kraft pulp properties of Pinus nigra J.F.Arnold and Abies bornmuelleriana Mattf.

Yasin ATAÇ, Hüdaverdi EROĞLU

Toxicity of native Bacillus thuringiensis isolates on the larval stages of pine processionary moth Thaumetopoea wilkinsoni at different temperatures

Semih YILMAZ, Salih KARABÖRKLÜ, Uğur AZİZOĞLU

Chitosan coating improves the shelf life and postharvest quality of table grape (Vitis vinifera) cultivar Shahroudi

Mohammad Ali SHIRI, Davood BAKHSHI, Mahmood GHASEMNEZHAD, Monad DADI

Mitigation effects of glycinebetaine on oxidative stress and some key growth parameters of maize exposed to salt stress

Cengiz KAYA, Osman SÖNMEZ, Salih AYDEMİR, Murat DİKİLİTAŞ

Interactions of Meloidogyne incognita, Xanthomonas campestris, and Rhizobium sp. in the disease complex of chickpea

Zaki Anwar SIDDIQUI, Munavvar FATIMA, Subha ALAM

Changes in the forage yield and quality of legume–grass mixtures throughout a vegetation period

Sebahattin ALBAYRAK, Mevlüt TÜRK

Development of a tractor dynamic stability index calculator utilizing some tractor specifications

İman AHMADI

Changes in the forage yield and quality of legume grass mixtures throughout a vegetation period

Mevlüt TÜRK, Sebahattin ALBAYRAK

Support vector machines in wood identification: the case of three Salix species from Turkey

Kemal TURHAN, Bedri SERDAR