Deriving Tree Diameter Growth and Probability of Survival Equations from Successive Diameter Distributions

2008 ◽  
Vol 54 (1) ◽  
pp. 31-35
Author(s):  
Thomas G. Matney ◽  
Emily B. Schultz
Keyword(s):  
General Procedure ◽  
Growth And Yield ◽  
Diameter Distribution ◽  
Diameter Growth ◽  
Individual Tree ◽  
Statistical Probability ◽  
Growth And Survival ◽  
Tree Diameter ◽  
Growth And Yield Models ◽  
Diameter Distributions

Abstract Many growth and yield models have used statistical probability distributions to estimate the diameter distribution of a stand at any age. Equations for approximating individual tree diameter growth and survival probabilities from dbh can be derived from these models. A general procedure for determining the functions is discussed and illustrated using a loblolly pine spacing study. The results from the spacing study show that it is possible to define tree diameter growth and survival probability functions from diameter distributions with an accuracy sufficient to obtain a link between the individual tree and diameter growth and yield models.

Calibrating predicted diameter distribution with additional information in growth and yield predictions

2003 ◽  
Vol 33 (3) ◽  
pp. 430-434 ◽  
Author(s):  
Annika Kangas ◽  
Matti Maltamo
Keyword(s):  
Growth Models ◽  
Basal Area ◽  
Growth And Yield ◽  
Diameter Distribution ◽  
Individual Tree ◽  
Forest Management Planning ◽  
Growing Stock ◽  
Additional Information ◽  
Tree Models ◽  
Diameter Distributions

Diameter distribution of the growing stock is essential in many forest management planning problems. The diameter distribution is the basis for predicting, for example, timber assortments of a stand. Usually the predicted diameter distribution is scaled so that the stem number (or basal area) corresponds to the measured value (or predicted future value), but it may be difficult to obtain a distribution that gives correct estimates for all known variables. Diameter distributions that are compatible with all available information can be obtained using an approach adopted from sampling theory, the calibration estimation. In calibration estimation, the original predicted frequencies are modified so that they respect a set of constraints, the calibration equations. In this paper, an example of utilizing diameter distributions in growth and yield predictions is presented. The example is based on individual tree growth models of Scots pine (Pinus sylvestris L.). Calibration estimation was utilized in predicting the diameter distribution at the beginning of the simulation period. Then, trees were picked from the distribution and their development was predicted with individual tree models. In predicting the current stand characteristics, calibrated diameter distributions proved to be efficient. However, in predicting future yields, calibration estimation did not significantly improve the accuracy of the results.

scholarly journals A Comparison of Loblolly Pine Plantation Growth and Yield Models for Inventory Updating

1996 ◽  
Vol 20 (1) ◽  
pp. 15-22 ◽  
Author(s):  
James S. Shortt ◽  
Harold E. Burkhart
Keyword(s):  
Loblolly Pine ◽  
Growth And Yield ◽  
Diameter Distribution ◽  
Distribution Models ◽  
Tree Model ◽  
Individual Tree ◽  
Parameter Recovery ◽  
Individual Tree Model ◽  
The Individual ◽  
Growth And Yield Models

Abstract Four different loblolly pine growth and yield models were evaluated for the purpose of updating forest inventory data. The types of growth and yield models examined were: a whole stand, a diameter distribution-parameter prediction, a diameter distribution-parameter recovery, and an individual tree model. Three different approaches were used to create fitting and validation data sets from permanent plot remeasurement data; each of the four growth and yield models was evaluated at varying projection periods. The periods used were 0, 3, 6, and 9 yr. Evaluations were based solely on the capability of each model to predict merchantable volume. In terms of root mean square error of prediction, the individual tree and whole stand models performed better than the diameter distribution models. At shorter projection periods, the individual tree model performed better than the whole stand model, but the whole stand approach was superior at the 9 yr period. Of the diameter distribution models, the parameter recovery model performed better for shorter periods than the parameter prediction model, but this difference diminished with longer periods. South. J. Appl. For. 20(1):15-22.

A Blind Spot in the Use of the Weibull Function for Modeling Diameter Distributions

2020 ◽  
Author(s):  
Adrian Norman Goodwin
Keyword(s):  
Lower Bound ◽  
Blind Spot ◽  
Forest Growth ◽  
Growth And Yield ◽  
Diameter Distribution ◽  
Absolute Difference ◽  
Weibull Function ◽  
Distribution Models ◽  
Difference Statistic ◽  
Diameter Distributions

Abstract Diameter distribution models based on probability density functions are integral to many forest growth and yield systems, where they are used to estimate product volumes within diameter classes. The three-parameter Weibull function with a constrained nonnegative lower bound is commonly used because of its flexibility and ease of fitting. This study compared Weibull and reverse Weibull functions with and without a lower bound constraint and left-hand truncation, across three large unthinned plantation cohorts in which 81% of plots had negatively skewed diameter distributions. Near-optimal lower bounds for the unconstrained Weibull function were negative for negatively skewed data, and the left-truncated Weibull using these bounds was 14.2% more accurate than the constrained Weibull, based on the Kolmogorov-Smirnov statistic. The truncated reverse Weibull fit dominant tree distributions 23.7% more accurately than the constrained Weibull, based on a mean absolute difference statistic. This work indicates that a blind spot may have developed in plantation growth modeling systems deploying constrained Weibull functions, and that left-truncation of unconstrained functions could substantially improve model accuracy for negatively skewed distributions.

Individual tree diameter growth modeling system for Dalat pine (Pinus dalatensis Ferré) of the upland mixed tropical forests

2021 ◽  
Vol 480 ◽  
pp. 118612
Author(s):  
Bao Huy ◽  
Le Canh Nam ◽  
Krishna P. Poudel ◽  
Hailemariam Temesgen
Keyword(s):  
Tropical Forests ◽  
Growth Modeling ◽  
Diameter Growth ◽  
Individual Tree ◽  
Tree Diameter

Evaluating the influence of stem form and damage on individual-tree diameter increment and survival in the Acadian Region: implications for predicting future value of northern commercial hardwood stands

2018 ◽  
Vol 48 (9) ◽  
pp. 1007-1019 ◽  
Author(s):  
Mark Castle ◽  
Aaron Weiskittel ◽  
Robert Wagner ◽  
Mark Ducey ◽  
Jereme Frank ◽  
...  
Keyword(s):  
Growth And Yield ◽  
Tree Level ◽  
Permanent Plots ◽  
Stem Form ◽  
Individual Tree ◽  
Tree Diameter ◽  
Diameter Increment ◽  
Hardwood Species ◽  
Future Value

Northern hardwood species display a variety of forms and defects that can reduce stem quality and complicate their timber management. However, for the most part, growth and yield models do not account for the influence of stem form and damage. This study determined the influence of stem form and damage on growth, survival, and projected future sawlog value among several northern commercial hardwood species. To accomplish this, hardwood trees on 112 permanent plots across three long-term research sites in Maine were assigned stem form and risk classes using a tree classification system developed in New Brunswick. A highly significant influence of stem form and risk on annualized individual-tree diameter increment and survival was found. Inclusion of these equations into a regional growth and yield model highlighted the importance of stem form and defects on long-term simulations as projected stand-level future value was significantly reduced by over 17%, on average (range of 13% to 28%), when compared with projections that did not include that tree-level information. The results highlight the importance of stem form and defects, as well as the need to account for them, in growth and yield applications that assess the forecasted value of commercially important hardwood stands.

scholarly journals  Modelling of tree diameter growth using growth functions parameterised by least squares and Bayesian methods

2012 ◽  
Vol 58 (No. 6) ◽  
pp. 245-252 ◽  
Author(s):  
R. Sedmák ◽  
L. Scheer
Keyword(s):  
Least Squares ◽  
Bayesian Methods ◽  
A Priori ◽  
Nonlinear Least Squares ◽  
Yield Function ◽  
Growth And Yield ◽  
Diameter Growth ◽  
Tree Diameter ◽  
Growth Functions ◽  
Future Growth

The purpose of this paper is to present a new growth and yield function (denoted as KM-function), which was empirically derived from the cumulative density function of the Kumaraswamy probability distribution. KM-function is theoretically well disposed for the prediction of future growth; however, the function also has other theoretical features that make it useful also for retrospective estimation of the past growth frequently used in biological analyses of growth in the initial life stages. In order to demonstrate the practical applicability of the KM-function for growth reconstruction, an investigation of the accuracy of five-year retrospective projections of the real tree diameters obtained by stem analyses of 35 beech trees was done. Bias and accuracy of the new function were compared with bias and accuracy of some well-known growth functions on the same database. Compared functions were parameterised in two ways: by the method of nonlinear least squares and Bayesian methods. Empirical validation of the KM-function confirmed its good theoretical properties when it was used for retrospective estimation of the tree diameter growth. The valuable knowledge of this research is also a finding that the incorporation of a great deal of a priori known facts about the growth of trees and stands in natural conditions of Slovakia into Bayesian parameter estimation led to a decrease in the bias and magnitude of reconstruction errors.  

scholarly journals Individual-Tree Diameter Growth Models for Mixed Nothofagus Second Growth Forests in Southern Chile

Forests ◽  
2017 ◽  
Vol 8 (12) ◽  
pp. 506 ◽  
Author(s):  
Paulo Moreno ◽  
Sebastian Palmas ◽  
Francisco Escobedo ◽  
Wendell Cropper ◽  
Salvador Gezan
Keyword(s):  
Growth Models ◽  
Diameter Growth ◽  
Southern Chile ◽  
Individual Tree ◽  
Tree Diameter ◽  
Second Growth ◽  
Diameter Growth Models

scholarly journals A percentile-based estimator for the log-logistic function: Application to forestry

2020 ◽  
Vol 72 (1) ◽  
pp. 107-120
Author(s):  
Friday Nwabueze Ogana
Keyword(s):  
Estimation Method ◽  
Tectona Grandis ◽  
Logistic Function ◽  
Growth And Yield ◽  
Estimation Methods ◽  
Diameter Distribution ◽  
Logistic Distribution ◽  
Forest Stands ◽  
Forest Modelling ◽  
Diameter Distributions

AbstractDeveloping a simplified estimation method without compromising the performance of the distribution is germane to forest modelling. Few estimation methods exist for the Log-Logistic distribution and are relatively complex. A simplified estimator for the Log-Logistic parameters will increase its application in diameter distribution yield systems. Therefore, in this study, a percentile-based estimator was applied for the Log-Logistic distribution. The Kolmogorov-Smirnov, Anderson-Darling and Cramer-von Mises statistics were used to evaluate the method in two natural forest stands and two monospecific plantations of Gmelina arborea Roxb. and Tectona grandis Linn. f. in Nigeria. The parameter recovery model (PRM) and parameter prediction model (PPM) were used to predict the diameter distributions of independent stands of G. arborea and T. grandis. The results showed that the percentile estimator did not compromise the quality of fits of the Log-Logistic function across the four forest stands and are comparable to the maximum likelihood estimator. The 25th and 75th, and 40th and 80th were the best sample percentiles for the estimator. The predicted diameter distributions of G. arborea and T. grandis stands from the PRM and PPM were reasonable and compare well with the observed distribution. Thus, either of the models can be incorporated into the growth and yield system of forest stand management.

Sign in / Sign up

Export Citation Format

Share Document