Nonlinear mixed-effects branch diameter and length models for natural Dahurian larch (Larix gmelini) forest in northeast China

Dong, Lingbo; Liu, Zhaogang; Bettinger, Pete

doi:10.1007/s00468-016-1356-y

Cited by 12 publications

(10 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results were consistent with previous similar studies conducted by Li et al [29] and Wang et al [15], who also used the Chapman-Richards growth function to study branch growth in Larix olgensis and P. koraiensis plantations. This could be attributed to the fact that the Chapman-Richards growth function is more suitable for describing the branch growth of coniferous tree species in plantation forests [42]. However, our study results differ from Dong et al [30], who used the Weibull growth function to study the branch growth of P. koraiensis under mixed forests.…”

Section: Base Model For the Gfblcontrasting

confidence: 92%

Modeling Free Branch Growth with the Competition Index for a Larix principis-rupprechtii Plantation

Liu

Wang

Zhang

et al. 2023

Forests

View full text Add to dashboard Cite

Competition among free branches in the tree canopy is an important factor influencing branch length growth. Therefore, there is a need to quantify this competition and to understand the impact of the regression technique on the predictive accuracy of the growth of free branch length (GFBL) model in a Larix principis-rupprechtii plantation. This study focused on an L. principis-rupprechtii plantation in Saihanba Mechanized Forest Farm. Five competition indices based on 2176-branch data points from 76 trees were used to quantify the branch competition, and three regression techniques (nonlinear least squares (NLS), nonlinear mixed-effects model (NLME), and nonlinear quantile regression (NQR)) were used to construct the GFBL model including the branch competition index. The results showed that the Chapman–Richards growth function, including the diameter at breast height (DBH) and depth of branch into crown (DINC), was the optimal equation for describing the GFBL in the studied L. principis-rupprechtii plantation. The branch competition index (CI) was found to be optimal for quantifying the branch competition when used with the maximum value parameter (a0) of the Chapman–Richards growth function. The three parameter estimation methods were compared, and the NLME, which included the CI, was found to have the highest predictive accuracy. The results of this study can act as a reference for improving the management, assessing the management effectiveness, and enhancing the quality of L. principis-rupprechtii plantations.

show abstract

Section: Base Model For the Gfblcontrasting

confidence: 92%

Modeling Free Branch Growth with the Competition Index for a Larix principis-rupprechtii Plantation

Liu

Wang

Zhang

et al. 2023

Forests

View full text Add to dashboard Cite

show abstract

“…Under these conditions, the D matrix, which must be a positive semidefinite matrix, is generally considered as the unstructured positive definite matrix in forest research (Dong et al 2016;Pinheiro and Bates 2000;Yang et al 2009b). We also used our dataset of stem taper to show that the evaluation indices, AIC and BIC, are the smallest when the D matrix is the unstructured positive matrix.…”

Section: Nonlinear Mixed-effects (Nlme) Modelsmentioning

confidence: 99%

Tree profile equations are significantly improved when adding tree age and stocking degree: an example for Larix gmelinii in the Greater Khingan Mountains of Inner Mongolia, northeast China

et al. 2020

View full text Add to dashboard Cite

Tree age (AGE) and stocking degree (P) strongly influence tree shape, but their effects have been neglected in most tree profile equations. In addition, data used to build traditional tree profile equations usually do not meet the statistical requirements of independence and identical distribution of observations. The main objectives were to present a method to improve taper equations with measurements easily collected in tree inventories (age, stocking degree) and also improve the statistical accuracy of those equations by selecting parameters with a more rigorous way than that is traditionally being done. We evaluated the effects of incorporating age and stocking degree as regressors in tree profile equations selected among 30 candidate foundation equations and parameterized with data from 1,858 Larix gmelinii (Rupr.) trees growing in the northern China. We used nonlinear mixed-effects models to minimize statistical problems present when building traditional tree profile equations: lack of independence and identical distribution of observations, random effects related to individual trees. Equations incorporating age and stocking degree significantly improved their accuracy. When the equation parameters were estimated with mixedeffects models containing exponential variance functions and accounting for non-independence of observations from the same tree, diameters at any height along the tree bole were more accurately estimated. We demonstrate a new methodology to build more accurate tree profile equations that could support better economic valorization of timber and improve calculations of carbon flows in forests, not only for natural L. gmelinii forest but for other species growing in dense natural stands around the globe.

show abstract

“…Compared to thick branches, thin branches had smaller fibers, which may be due to the effects of the cambial age and the control of the meristem at the top of the branches (Nicolini et al 2001;Peterson et al 2007). The branch diameter is an important tree variable in plantation management because it has considerable influence on the tree growth, timber quality, fruit yield, and important physiological processes (Dong et al 2016;Royer-Tardif et al 2017;Jin et al 2019). Although significant correlations exist between the fiber morphometrics and the diameters of the branches at pvalue less than 0.05 or p-value less than 0.01 levels, the branch diameter may not be adequate to forecast fiber morphometrics, due to the absolute value of Pearson's correlation coefficients (r is less than 0.13).…”

Section: The Effect Of the Branch Diametermentioning

confidence: 99%

Fiber morphology in walnut branchwood: Relation to the branch diameter, branching level, and tension wood

Guo

Zhao

Liu

et al. 2022

BioRes

View full text Add to dashboard Cite

The branchwood of fruit trees is being promoted to supplement the fiber material for paper manufacturing in China. This study was conducted to investigate the fiber morphology of walnut branchwood, and to highlight its potential utilizations in papermaking. The effects of the branch diameter, branching level, and tension wood on the fiber morphology were also investigated. The results showed that approximately 65% of the fibers were longer than 900 µm, 95% of the fibers had a slenderness ratio greater than 40, and 67% of the fibers had a Runkel ratio less than 1. It is evident from the results that the fiber morphology of walnut branchwood is reasonably good for paper manufacturing. However, the diameter of the branch does not provide reliable information to predict the fiber morphometrics. In addition, the branching level and tension wood are not very helpful in the screening of fiber raw materials.

show abstract

Nonlinear mixed-effects branch diameter and length models for natural Dahurian larch (Larix gmelini) forest in northeast China

Cited by 12 publications

References 31 publications

Modeling Free Branch Growth with the Competition Index for a Larix principis-rupprechtii Plantation

Modeling Free Branch Growth with the Competition Index for a Larix principis-rupprechtii Plantation

Tree profile equations are significantly improved when adding tree age and stocking degree: an example for Larix gmelinii in the Greater Khingan Mountains of Inner Mongolia, northeast China

Fiber morphology in walnut branchwood: Relation to the branch diameter, branching level, and tension wood

Contact Info

Product

Resources

About