iForest - Biogeosciences and Forestry


Modeling compatible taper and stem volume of pure Scots pine stands in Northeastern Turkey

Burak Saygili (1), Aydin Kahriman (2)   

iForest - Biogeosciences and Forestry, Volume 16, Issue 1, Pages 38-46 (2023)
doi: https://doi.org/10.3832/ifor4099-015
Published: Jan 22, 2023 - Copyright © 2023 SISEF

Research Articles

Compatible taper and volume equations for pure and natural Scots pine stands in the northeastern part of Turkey (Ardahan Province) were developed using a nonlinear mixed-effects modeling approach. Experimental data were obtained from 137 felled sample trees in different diameter and height classes. The most successful model (Jiang et al. 2005) explained 98.3% of the variance in stem diameter estimation and the RMSE, ME, MAE, AIC and BIC value obtained using this model were 1.955 cm, 0.043 cm, 1.300 cm, 9783.8 and 9812.6, respectively. Considering the criterion values of AIC, BIC and -2LnL, the model with random-effects in two parameters (b1 and b3) was the most successful for Scots pine. While the mixed model including random parameters did not completely solved the problem of the autocorrelation of errors in this study, the use of the autoregressive error structure AR(1) eliminated the autocorrelation in the residuals. In addition, the best estimation results among 20 different calibration options were obtained using the option of measuring two tree diameters at d1.30 and d5.30 with validation data. The most successful model explained 99.18% of the total variance in stem volume estimation in Scots pine.


Nonlinear Mixed-effects Model, Segmented Polynomial Taper Models, Calibration, Random Parameters, Autocorrelation, Stem Volume

Authors’ address

Burak Saygili 0000-0003-0106-0550
Erzurum Regional Directorate Ardahan Forest District Directorate, 75000, Ardahan (Turkey)
Aydin Kahriman 0000-0001-9696-1153
Artvin Çoruh University Faculty of Forestry, Department of Forest Engineering, 08100, Artvin (Turkey)

Corresponding author

Aydin Kahriman


Saygili B, Kahriman A (2023). Modeling compatible taper and stem volume of pure Scots pine stands in Northeastern Turkey. iForest 16: 38-46. - doi: 10.3832/ifor4099-015

Academic Editor

Carlotta Ferrara

Paper history

Received: Mar 11, 2022
Accepted: Nov 07, 2022

First online: Jan 22, 2023
Publication Date: Feb 28, 2023
Publication Time: 2.53 months

Breakdown by View Type

(Waiting for server response...)

Article Usage

Total Article Views: 634
(from publication date up to now)

Breakdown by View Type
HTML Page Views: 0
Abstract Page Views: 0
PDF Downloads: 544
Citation/Reference Downloads: 0
XML Downloads: 90

Web Metrics
Days since publication: 490
Overall contacts: 634
Avg. contacts per week: 9.06

Article Citations

Article citations are based on data periodically collected from the Clarivate Web of Science web site
(last update: Nov 2020)

(No citations were found up to date. Please come back later)


Publication Metrics

by Dimensions ©

Articles citing this article

List of the papers citing this article based on CrossRef Cited-by.

Adamec Z, Adolt R, Drápela K, Závodsky J (2019)
Evaluation of different calibration approaches for merchantable volume predictions of Norway spruce using nonlinear mixed effects model. Forests 10 (12): 1104.
CrossRef | Gscholar
Anonymous (2016)
Turkish State meteorological service. Artvin Meteorological Station Climate Data (1927-2016). Artvin, Turkey, pp. 14.
Atalay F (2014)
Developing compatible taper and volume equations for Crimean Pine (Pinus nigra Arnold. subsp. pallasiana [Lamb.] Holmboe) in Mudurnu-Sirçali Forest District Enterprise. M.Sc. Thesis, Çankiri Karatekin University, Graduate School of Natural and Applied Sciences, Çankiri, Turkey, pp. 47.
Barrio-Anta M, Dieguez-Aranda U, Castedo-Dorado F, Alvarez-Gonzalez JG, Gadow K (2007)
Merchantable volume system for pedunculate oak in northwestern Spain. Annals of Forest Science 64 (5): 511-520.
CrossRef | Gscholar
Bi H (2000)
Trigonometric variable-form taper equations for Australian eucalyptus. Forest Science 46: 397-409.
Online | Gscholar
Çakir CY, Kahriman A (2018)
Modeling stem profile of Caucasian fir and Oriental spruce mixed stands in Turkey using nonlinear mixed-effects models. Applied Ecology and Environmental Research 16 (5): 6815-6833.
Online | Gscholar
Cao QV, Wang J (2011)
Calibrating fixed- and mixed-effects taper equations. Forest Ecology and Management 262: 671-673.
CrossRef | Gscholar
Castedo-Dorado F, Diéguez-Aranda U, Barrio M, Sánchez M, Gadow K (2006)
A generalized height-diameter model including random components for radiata pine plantations in northeastern Spain. Forest Ecology and Management 229: 202-213.
CrossRef | Gscholar
Clark III A, Souter RA, Schlaegel BE (1991)
Stem profile equations for southern tree species. Research Paper no. SE-282, USDA Forest Service, NC, USA, pp. 117.
Online | Gscholar
Demaerschalk JP (1973)
Integrated systems for the estimation of tree taper and volume. Canadian Journal of Forest Research 3 (1): 90-94.
CrossRef | Gscholar
Diéguez-Aranda U, Castedo-Dorado F, Alvarez-Gonzalez JG, Rojo A (2006)
Compatible taper function for Scots pine plantations in Nortwestern Spain. Canadian Journal of Forest Research 36: 1190-1205.
CrossRef | Gscholar
Doyog ND, Lee YJ, Lee S (2017)
Stem taper equation analysis for Larix kaempferi species in the central region of South Korea. Journal of Sustainable Forestry 36 (8): 747-763.
CrossRef | Gscholar
Fang Z, Borders BE, Bailey RL (2000)
Compatible volume taper models for loblolly and slash pine based on system with segmented-stem form factors. Forest Science 46: 1-12.
Online | Gscholar
Garber SM, Maguire DA (2003)
Modeling stem taper of three central Oregon species using nonlinear mixed effects models and autoregressive error structures. Forest Ecology and Management 179: 507-507.
CrossRef | Gscholar
GDF (2015)
Forests of Turkey. Publications of the Turkey General Directorate of Forests, Ankara, Turkey, pp. 219.
Gómez-García E, Crecente-Campo F, Diéguez-Aranda U (2013)
Selection of mixed-effects parameters in a variable-exponent taper equation for birch trees in northwestern Spain. Annals of Forest Science 70: 707-715.
CrossRef | Gscholar
He P, Hussain A, Shahzad MK, Jiang L, Li F (2021)
Evaluation of four regression techniques for stem taper modeling of Dahurian larch (Larix gmelinii) in Northeastern China. Forest Ecology and Management 494: 119336.
CrossRef | Gscholar
Hirigoyen A, Navarro-Cerrillo R, Bagnara M, Franco J, Resquin F, Rachid Casnati C (2021)
Modelling taper and stem volume considering stand density in Eucalyptus grandis and Eucalyptus dunnii. iForest - Biogeosciences and Forestry 14 (2): 127-136.
CrossRef | Gscholar
Hussain A, Shahzad MK, He P, Jiang L (2020)
Stem taper equations for three major conifer species of Northeast China. Scandinavian Journal of Forest Research 35 (8): 562-576.
CrossRef | Gscholar
Hussain A, Shahzad MK, Burkhart HE, Jiang L (2021)
Stem taper functions for white birch (Betula platyphylla) and costata birch (Betula costata) in the Xiaoxing’an Mountains, northeast China. Forestry 94: 714-733.
CrossRef | Gscholar
Jiang L, Brooks JR, Wang J (2005)
Compatible taper and volume equations for yellow-poplar in West Virginia. Forest Ecology and Management 213: 399-409.
CrossRef | Gscholar
Kahriman A, Sönmez T, Gadow K (2018)
Site index models for Calabrian pine in the central Mediterranean region of Turkey. Journal of Sustainable Forestry 37 (5): 459-474.
CrossRef | Gscholar
Keselman HJ, Algina J, Kowalchuk RK, Wolfinger RD (1998)
A comparison of two approaches for selecting covariance structures in the analysis of repeated measures. Communications in Statistics - Computation and Simulation 27 (3): 591-604.
CrossRef | Gscholar
Koirala A, Montes CR, Bullock BP, Wagle BH (2021)
Developing taper equations for planted teak (Tectona grandis L. f.) trees of central lowland Nepal. Trees, Forests and People 5: 100103.
CrossRef | Gscholar
Kozak A (2004)
My last words on taper equations. Forest Chronicle 80: 507-515.
CrossRef | Gscholar
Kumas G, Kahriman A (2016)
Development of compatible taper and volume equations for Calabrian pine in Antalya Regional Directorate. Artvin Çoruh University Journal of Forestry Faculty 17 (1): 21-31.
Kurt AK (2014)
Developing stem taper and stem volume equations using nonlinear mixed effect modeling approach for Crimean pine stands (Pinus nigra Arnold. subsp. pallasiana [Lamb.) Holmboe) in Tarsus Forest Enterprise. MSc Thesis, Çankiri Karatekin University Graduate School of Natural and Applied Sciences, Çankiri, Turkey, pp. 77.
Laar AV, Akça A (2007)
Forest mensuration. In: “Managing Forest Ecosystems”. Springer, Dordrecht, The Netherlands, pp. 383.
Lee WK, Seo JH, Son YM, Lee KH, Von Gadow K (2003)
Modeling stem profiles for Pinus densiflora in Korea. Forest Ecology and Management 172: 69-77.
CrossRef | Gscholar
Leites LP, Robinson AP (2004)
Improving taper equations of loblolly pine with crown dimensions in a mixed-effects modeling framework. Forest Science 50: 204-212.
Online | Gscholar
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. Annals of Forest Science 67: 302.
CrossRef | Gscholar
Max TA, Burkhart HE (1976)
Segmented polynomial regression applied to taper equations. Forest Science 22 (3): 283-289.
Online | Gscholar
Ozçelik R, Brooks JR, Jiang L (2011)
Modeling stem profile of Lebanon cedar, Brutian pine, and Cilicica fir in Southern Turkey using nonlinear mixed-effects models. European Journal of Forest Research 130: 613-621.
CrossRef | Gscholar
Ozçelik R, Bal C (2013)
Effects of adding crown variables in stem taper and volume predictions for black pine. Turkish Journal of Agriculture and Forestry 37: 231-242.
CrossRef | Gscholar
Ozçelik R, Alkan O (2020)
Fitting and calibrating a mixed-effects segmented taper model for Brutian pine. Cerne 26 (4): 464-473.
CrossRef | Gscholar
Parresol BR, Hotvedt JE, Cao QV (1987)
A volume and taper prediction system for bald cypress. Canadian Journal of Forest Research 17: 250-259.
CrossRef | Gscholar
Pukkala T, Hanssen K, Andreassen K (2019)
Stem taper and bark functions for Norway spruce in Norway. Silva Fennica 53: 10187.
CrossRef | Gscholar
Quiñonez-Barraza G, Zhao D, De Los Santos-Posadas HM (2019)
Compatible taper and stem volume equations for five pine species in mixed-species forests in Mexico. Forest Science 65 (5): 602-613.
CrossRef | Gscholar
Sahin D (2012)
Development of compatible taper and volume equatons for black pine stands. M.Sc. Thesis, Graduate School of Applied and Natural Sciences, Süleyman Demirel University, Isparta, Turkey, pp. 64.
Sakici OE, Misir N, Yavuz H, Misir M (2008)
Stem taper functions for Abies nordmanniana subsp. bornmulleriana in Turkey. Scandinavian Journal of Forest Reearch 23: 522-533.
CrossRef | Gscholar
Salekin S, Catalán CH, Boczniewicz D, Phiri D, Morgenroth J, Meason DF, Mason EG (2021)
Global tree taper modelling: a review of applications, methods, functions, and their parameters. Forests 12: 913.
CrossRef | Gscholar
SAS Institute (2013)
SAS/IML v. 9.3 user’s guide. SAS Institute Inc., Cary, USA, pp. 1097.
Searle SR, Casella G, Mc Culloch CE (1992)
Variance components. John Wiley and Sons Inc., Hoboken, NJ, USA, pp. 501.
CrossRef | Gscholar
Senyurt M, Ercanli I, Bolat F (2017)
Taper equations based on nonlinear mixed effect modeling approach for Pinus nigra in Çankiri forests. Bosque 38 (3): 545-554.
CrossRef | Gscholar
Sharma M, Parton J (2009)
Modeling stand density effects on taper for jack pine and black spruce plantations using dimensional analysis. Forest Science 55 (3): 268-282.
Online | Gscholar
Sönmez T, Kahriman A, Yavuz M (2016)
Biomass equations for Calabrian pine in the Mediterranean region of Turkey. Šumarski List 140 (11-12): 567-576.
Trincado G, Burkhart HE (2006)
A generalized approach for modeling and localizing stem profile curve. Forest Science 52 (6): 670-682.
Online | Gscholar
Valentine HT, Gregoire TG (2001)
A switching model of bole taper. Canadian Journal of Forest Research 31 (8): 1400-1409.
CrossRef | Gscholar
Yang Y, Huang S, Meng SX (2009)
Development of a tree-specific stem profile model for white spruce: a nonlinear mixed model approach with a generalized covariance structure. Forestry 82 (5): 541-555.
CrossRef | Gscholar
Ye S (2005)
Covariance structure selection in linear mixed models for longitudinal data. M.Sc. Thesis, Department of Bioinformatics and Biostatistics, University of Lousville, KC, USA. pp. 115.
Online | Gscholar
Zhao D, Lynch TB, Westfall J, Coulston J, Kane M, Adams DE (2019)
Compatibility, development, and estimation of taper and volume equation systems. Forest Science 65 (1): 1-13.
CrossRef | Gscholar

This website uses cookies to ensure you get the best experience on our website. More info