scholarly journals Taper models for black locust in west Poland

Silva Fennica ◽  
2020 ◽  
Vol 54 (5) ◽  
Author(s):  
Karol Bronisz ◽  
Michał Zasada
Keyword(s):  
Fixed Effects ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Mixed Effects ◽  
Forest Management Planning ◽  
Estimated Parameters ◽  
Types Of Information ◽  
Volume Equations ◽  
Taper Model ◽  
Taper Models

The diameter at any point on a stem and tree volume are some of the most important types of information used in forest management planning. One of the methods to predict the diameter at any point on a stem is to develop taper models. Black locust ( L.) occurs in almost all forests in Poland, with the largest concentration in the western part of the country. Using empirical data obtained from 13 black locust stands (48 felled trees), seven taper models with different numbers of estimated parameters were analysed for section diameters both over and under bark using fixed and mixed-effects modelling approaches. Assuming a lack of additional measurements, the best fitted taper models were used for the prediction of over bark volume using both methods. The predicted volume was compared with the results from different volume equations available for black locust. The variable-form taper model with eight estimated parameters fitted the data the best. The lowest root mean square error for volume prediction was achieved for the elaborated fixed-effects taper model (0.0476), followed by the mixed-effects taper model (0.0489). At the same time, the difference between the volume relative errors achieved based on the taper models does not differ significantly from the results obtained using the volume equations already available for black locust (two of the three analysed).Robinia pseudoacacia

scholarly journals Comparison of Fixed- and Mixed-effects Approaches to Taper Modeling for Scots Pine in West Poland

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 975 ◽  
Author(s):  
Karol Bronisz ◽  
Michał Zasada
Keyword(s):  
Random Effects ◽  
Scots Pine ◽  
Fixed Effects ◽  
Mixed Effects ◽  
Mixed Effects Model ◽  
Fixed Effects Model ◽  
Validation Data ◽  
Data Set ◽  
Taper Model ◽  
Model Approach

Diameter measurements along the stem, which are the basis for taper models, usually have a hierarchical structure. Mixed-effects models, where fixed and random effects are distinguished, are a possible solution for this type of data. However, in order to fully absorb the potential of this method, random effects prediction, which requires additional measurements (diameter along stem), is recommended. This article presents a comparison of various fitting methods (mixed- and fixed-effects model approaches) of the variable-exponent taper model created by Kozak for determining the outside bark diameter along the stem and predicting the tree volume of Scots pine trees in west Poland. During the analysis, it was assumed that no additional measured data were available for practical use; therefore, for the mixed-effects model approach, fixed effects prediction without random effects was applied. Both fitting strategies were compared based on modeling and an independent validation data set. The comparison of mixed- and fixed-effects fitting strategies for the diameter along the stem indicated that the taper model fitted using the mixed-effects model approach better fit the data. Moreover, the error rate for the total tree volume prediction for the independent data set was lower for the mixed-effects model solution than for the fixed-effects one.

Improved allometric equations for black locust (Robinia pseudoacacia) in the Coweeta Basin

2021 ◽  
Author(s):  
Joel L. Scott ◽  
Chelcy F. Miniat ◽  
Jessie Motes ◽  
Sarah L. Ottinger ◽  
Nina Wurzburger ◽  
...  
Keyword(s):  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Allometric Equations

scholarly journals HEAT-INDUCED CHEMICAL AND COLOR CHANGES OF EXTRACTIVE-FREE BLACK LOCUST (ROBINIA PSEUDOACACIA) WOOD

BioResources ◽  
2012 ◽  
Vol 7 (2) ◽  
Author(s):  
Yao Chen ◽  
Jianmin Gao ◽  
Yongming Fan ◽  
Mandla A. Tshabalala ◽  
Nicole M. Stark
Keyword(s):  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Color Changes ◽  
Free Black

scholarly journals Slenderness of trees in black locust stands

2018 ◽  
Vol 79 (2) ◽  
pp. 113-117
Author(s):  
Szymon Bijak ◽  
Katarzyna Orzoł
Keyword(s):  
Standard Deviation ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Habitat Type ◽  
Stand Age ◽  
Age Classes ◽  
Breast Height ◽  
Age Class ◽  
Crown Length ◽  
Research Material

Abstract This paper investigates the slenderness of black locust (Robinia pseudoacacia) trees in relation to the biosocial status of the trees, stand age class, crown parameters and habitat type. The research material was collected on 35 research plots in the Sława Śląska, Sulechów and Głogów forest districts in western Poland and comprises 1058 trees. For each tree, we measured height (h) as well as diameter at breast height (d) and determined its biosocial status (Kraft class), crown length (CL) and relative crown length (rCL). The age class and habitat type were assessed at the plot level. Because the obtained values for slenderness (s=h/d) diverged significantly from the normal distribution, we used Kruskal-Wallis and Mann-Whitney tests to investigate the influence of the above-mentioned parameters on the h/d ratio. Black locust slenderness ranged from 0.31 to 1.95 with an average of 0.91 (standard deviation 0.24). It furthermore differed significantly between Kraft classes (the higher the biosocial status, the lower the slenderness) and age classes (the older the trees, the lower their slenderness). We also found a significant effect of the habitat type (in oligotrophic sites trees formed more slender trunks than in mesotrophic sites) and crown parameters on the h/d ratio (decreasing with increasing crown length and relative crown length). The obtained results suggest that the slenderness of black locust does not differ substantially from native broadleaved trees in Poland.

scholarly journals Propagation from root cuttings for black locust (Robinia pseudoacacia L.) improvement in Hungary: a review

2019 ◽  
Vol 25 (1-2) ◽  
Author(s):  
Zs. Keserű ◽  
K. Rédei ◽  
J. Rásó ◽  
T. Kiss
Keyword(s):  
Genetic Variation ◽  
Forest Management ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Clonal Forestry ◽  
Wood Production ◽  
The World ◽  
More Care ◽  
Improved Cultivars ◽  
Robinia Pseudoacacia L

Black locust (Robinia pseudoacacia L.) is a valuable stand-forming tree species introduced to Europe approximately 400 years ago from North America. Today it is widely planted throughout the world, first of all for wood production. In Hungary, where black locust has great importance in the forest management, it is mainly propagated by seeds. But since the seed-raised plants present a great genetic variation, this type of propagation can not be used for Robinia’s improved cultivars. In the Hungarian black locust clonal forestry, propagation from root cuttings can be used for reproduction of superior individuals or cultivars in large quantities. However, this method demands more care than raising seedlings from seeds and can be applied with success in well-equipped nurseries.

scholarly journals Productivity of black locust (Robinia pseudoacacia L.) stands on chernozem in Vojvodina

2014 ◽  
pp. 9-31
Author(s):  
Sinisa Andrasev ◽  
Savo Roncevic ◽  
Petar Ivanisevic ◽  
Sasa Pekec ◽  
Martin Bobinac
Keyword(s):  
Soil Type ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Diameter Growth ◽  
Sample Plot ◽  
Considerable Variability ◽  
Aeolian Sand ◽  
Breast Height ◽  
The Mean ◽  
Robinia Pseudoacacia L

This paper presents the elements of growth of black locust trees and stands in 15 sample plots in Vojvodina, at the age of 21-68 years. In each sample plot, based on soil profile horizons the determined soil type was chernozem as well as its lower systematic units (subtype, variety and form), according to the Skoric et al. (1985) classification. On the basis of the mean stand heights (hL), the stands on the subtype of chernozem on loess and loesslike sediments belong to height classes I-IV, and stands on calcareous aeolian sand to classes II-V (according to R e d e i et al. 2014), which indicates their considerable variability with respect to productivity within the determined subtypes of chernozem. Significant differences at the level of chernozem subtypes were found between the mean heights (p = 0.032), but not between the mean diameters (p = 0.083). The mean diameters at breast height in the studied black locust stands were on average lower than the models of diameter growth for the appropriate height classes and determined by a larger number of trees per hectare than in the tables (R e d e i et al, 2014). The volume per hectare is higher than in the tables also being conditioned by the large number of trees per hectare.

Sign in / Sign up

Export Citation Format

Share Document