scholarly journals USE OF DUMMY VARIABLES TO PREDICT GROWTH STRESSES IN Eucalyptus ssp. CLONES

2016 ◽  
Vol 40 (6) ◽  
pp. 1131-1139
Author(s):  
Rafael Beltrame ◽  
Pedro Henrique Gonzalez Cadermatori ◽  
Rafael de Avila Delucis ◽  
Darci Alberto Gatto ◽  
Clovis Roberto Haselein ◽  
...  
Keyword(s):  
Residual Strain ◽  
Basic Density ◽  
Morphological Properties ◽  
Bark Thickness ◽  
Technological Properties ◽  
Dummy Variables ◽  
Growth Stresses ◽  
Independent Variables ◽  
Breast Height ◽  
Hybrid Eucalyptus

ABSTRACT The evaluation of growth stresses in Eucalyptus trees and their influence on both morphological properties of trees and technological properties of wood have been aimed by several studies, which used indirect and nondestructive methods for these evaluations. The present study aimed to estimate growth stresses for woods from Eucalyptus ssp. clones trough some of their dendrometric properties, using Dummy variables. 12 hybrid Eucalyptus clones were evaluated by basic density (BD) and dendrometric properties: diameter at breast height (DBH), bark thickness (BT), height (H) and total volume (VOL). The growth stresses were indirectly evaluated by the longitudinal residual strain (LRS) following the CIRAD-Forêt method. 12 Dummy variables were defined based on the characteristics of each clone. After that, four models were proposed in order to estimate the LRD, using Dummy variables, DBH, H, VOL and BD as independent variables. Among the dendrometric properties, BD was discarded because it does not confer interesting aids to the LRD predict. Among the Dummy variables, clone 9 provided the most discrepant variable. The LRD of the clones were satisfactorily described by the mathematical models, although these values showed significant variability.

WITHIN AND BETWEEN-TREE VARIATION OF BARK CONTENT AND WOOD DENSITY OF EUCALYPTUS GLOBULUS IN COMMERCIAL PLANTATIONS

IAWA Journal ◽  
2001 ◽  
Vol 22 (3) ◽  
pp. 255-265 ◽  
Author(s):  
Teresa Quilhó ◽  
Helena Pereira
Keyword(s):  
Wood Density ◽  
Tree Growth ◽  
Eucalyptus Globulus ◽  
Basic Density ◽  
Dry Weight ◽  
Bark Thickness ◽  
Reasonable Accuracy ◽  
Wood Basic Density ◽  
Breast Height ◽  
Coefficients Of Variation

Eucalyptus globulus trees, 15 years old, were sampled at different heights from commercial pulpwood plantations in two sites in Portugal. Bark thickness was higher in the site with better growth and always decreased from the tree base to the top. Bark content was site independent and on average 11% of stem dry weight, higher at the base and top, and lower at 35% height level.Tree mean wood basic density averaged 600 kg /m3 and 568 kg /m3 for best and worst site, respectively, and was not correlated with tree growth. Wood density increased from base to top of the tree. Between-tree variation was low with coefficients of variation of site mean below 10%. Bark density (374 kg /m3 and 454 kg /m3 for best and worst site, respectively) did not show significant within tree variation. Average tree wood density could not be predicted with reasonable accuracy using a breast height sampling and better results were obtained using a sampling as a percentage of total height (e.g. 15%).

scholarly journals Italian alder (Alnus cordata/Loisel./Desf.) - new species for Allochtonous dendroflora of Serbia

2015 ◽  
pp. 21-36
Author(s):  
Martin Bobinac ◽  
Sinisa Andrasev ◽  
Marko Perovic ◽  
Andrijana Bauer-Zivkovic ◽  
Djura Jorgic
Keyword(s):  
Urban Areas ◽  
Meteorological Station ◽  
Great Variability ◽  
Morphological Properties ◽  
Forest Plantations ◽  
Absolute Minimum ◽  
Height Range ◽  
Breast Height ◽  
Fast Growing Species ◽  
Minimum Air Temperature

The foreign tree species, Alnus cordata/Loisel./Desf. (Italian alder), (Betulaceae/Loisel./Duby), not previously recorded in the dendroflora of Serbia, is described in this paper. Italian alder trees in an experimental plot in the area of Erdevik, aged 11 years, show good vitality and fast growth, and bear fruits since their 10th year. Tree heights are in range from 10.4 to 16.2 m, and diameters at the breast height range from14.6 to 34.9 cm. The morphological properties of leaves, fruiting organs (?cones?) and male catkins are in concordance with the values in literature sources, although they show great variability. Since the time of plantation establishment, the absolute minimum air temperature in the nearby meteorological station of Sremska Mitrovica was -26.50C, so it can be assumed that the species is frost hardy. On the basis of the researched properties of Italian alder, it can be concluded that this species can be cultivated in Serbia as an ornamental in urban areas and as a fast growing species in forest plantations for biomass production.

scholarly journals Modelling Bark Thickness of Norway Spruce (Picea abies Karst)

2019 ◽  
Vol 10 (2) ◽  
pp. 125-135
Author(s):  
Jusuf Musić ◽  
Velid Halilović ◽  
Jelena Knežević ◽  
Admir Avdagić ◽  
Aida Ibrahimspahić ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Bosnia And Herzegovina ◽  
Timber Harvesting ◽  
Bark Thickness ◽  
Optimal Model ◽  
Breast Height ◽  
Starting Point ◽  
Mean Diameter ◽  
The Mean ◽  
Actual Method

Background and Purpose: Bark thickness and its share in the volume of roundwood are the most important characteristics of the bark, particularly in the process of timber harvesting, and during scaling of processed logs. Therefore it is very important to have at disposal relatively accurate data regarding these characteristics of bark for particular tree species. The main goal of this paper is to investigate the thickness of the bark and its share in the volume of roundwood of Norway spruce. Materials and Methods: The research was carried out in the area of the Canton 10 of the Federation of Bosnia and Herzegovina and it encompassed 393 trees of Norway spruce from 10 cm to 115 cm of thickness at breast height. Measuring of the mean diameter and double thickness of bark was conducted by section method. In total, 4,647 diameters and bark thicknesses were measured in different relative lengths of stems or in average 10.6 measurements per one stem. Results: As an optimal model for the evaluation of double thickness of the bark of Norway spruce depending on mean diameter of roundwood the function with designated determination coefficient of 0.7142 was selected. The obtained results have confirmed the previously defined relations of investigate characteristics, which are as following: a) with the increase of mean diameter of roundwood (section) double bark thickness is increased from 9.26 mm (thickness class 12.5 cm) to 31.65 mm (thickness class 92.5 cm); b) with the increase of mean diameter of roundwood the share of bark in its volume decreased from 14.26% (thickness class 12.5 cm) to 6.73% (thickness class 92.5 cm). Conclusions: By the actual method of estimating bark thickness or the share of bark in the volume of roundwood of Norway spruce in the forestry of the Federation of Bosnia and Herzegovina a significant error was created which increases with the increase of mean diameter. The obtained results point to the necessity of investigation of these bark characteristics in Bosnia and Herzegovina and represent an inevitable starting point for making adequate tables of bark thickness and its percentage share in the volume of roundwood of Norway spruce.

Within-Tree Variation in Wood Fibre Biometry And Basic Density of the Urograndis Eucalypt Hybrid (Eucalyptus Grandis × E. Urophylla)

IAWA Journal ◽  
2006 ◽  
Vol 27 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Teresa Quilhó ◽  
Isabel Miranda ◽  
Helena Pereira
Keyword(s):  
Wall Thickness ◽  
Fibre Length ◽  
Eucalyptus Grandis ◽  
Basic Density ◽  
Wood Properties ◽  
Axial Variation ◽  
Average Fibre ◽  
Length Width ◽  
Hybrid Eucalyptus ◽  
Old Trees

Within-tree variations in fibre length, width, wall thickness and wood basic density of Eucalyptus grandis × E. urophylla (urograndis) were studied in five 6.8-yr-old seedling trees and five 5.6-yr-old trees from one clone from Brazil. Samples were taken at 5%, 25%, 35%, 55%, 65% and 90% of stem height and five radial positions (10%, 30%, 50%, 70% and 90% of radius). The tree average fibre length, width and wall thickness were in seed and clone trees: 0.955 mm and 1.064 mm, 18 μm and 20 μm, 3.6 μm and 4.4 μm respectively. The axial variation of fibre dimensions was very low, while there was a consistent but small increasing trend from pith to periphery. The basic density ranged from 397–464 kg/m3 to 486–495 kg/m3 respectively in seedling and clone trees with a low variation along the stem. In comparison with other eucalypt pulpwood, e.g. E. globulus, the urograndis hybrid showed similar fibre dimensions and lower basic density. Overall the within-tree variation of these wood properties was low and age had a small impact on the variation of density and fibre dimensions.

Office and Industrial

2002 ◽  
Author(s):  
Grant Ian Thrall
Keyword(s):  
Real Estate ◽  
Real Estate Market ◽  
Regression Equation ◽  
Hedonic Models ◽  
Commercial Building ◽  
Dummy Variables ◽  
The Real Estate ◽  
Market Rent ◽  
Independent Variables ◽  
Commercial Space

A developer needs advice on the market for commercial space, including office and industrial properties. An owner of a commercial building needs to determine how much to charge for leased space, how much to sell the property for, or how much the property can be refinanced for. A purchaser needs to determine if market conditions support purchasing commercial space, or renting, and at what price. The real estate market analyst is responsible for the creation and assembly of information to guide such decisions. A background overview of real estate market analysis for the product categories of office and industrial projects is presented. The hedonic approach hypothesizes that a variety of phenomena contribute in one way or another to determining market rent. In a hedonic model, office or industrial property rent or occupancy rate may be the dependent variable of a regression equation, as explained in chapter 4. The phenomena that are hypothesized to cause the value of the dependent variable are the independent variables of the regression equation. Some examples of independent variables that have been hypothesized and examined in hedonic models as to their contribution to determining office market rent are listed below: . . . Terms of lease (Glascock et al. 1990). Architectural design (Hough and Kratz 1983) Building characteristics (Vandell and Lane 1989) Access to white collar employment (Clapp 1980) Local property tax rates (Wheaton 1984) Status and prestige (Archer 1981; Archer et al. 1990) Agglomeration—benefits of high geographic concentrations of specialized office establishments for specific kinds of industry (Gad 1979; Kroll 1984) Spillovers from close geographic proximity (Clapp et al. 1992). . . . Hedonic models might also include dummy variables as independent variables to represent the presence of some characteristic or phenomenon. The dummy variables have an assigned the value of 1.0 to denote the occurrence of some characteristic and 0.0 to denote its absence. An expectation must be developed by the analyst on how markets and submarkets differ in their rents, vacancy rates, and absorption rates and what their trend is expected to be.

scholarly journals How does bark contribution to postural control change during tree ontogeny? A study of six Amazonian tree species

2020 ◽  
Vol 71 (9) ◽  
pp. 2641-2649
Author(s):  
Romain Lehnebach ◽  
Tancrède Alméras ◽  
Bruno Clair
Keyword(s):  
Tensile Stress ◽  
Compressive Stress ◽  
Residual Strain ◽  
Tree Species ◽  
Bark Thickness ◽  
Relative Thickness ◽  
Allometric Relationship ◽  
Stem Size ◽  
Control Change ◽  
Bark Anatomy

Abstract Recent works revealed that bark is able to produce mechanical stress to control the orientation of young tilted stems. Here we report how the potential performance of this function changes with stem size in six Amazonian species with contrasted bark anatomy. The potential performance of the mechanism depends both on the magnitude of bark stress and the relative thickness of the bark. We measured bark longitudinal residual strain and density, and the allometric relationship between bark thickness and stem radius over a gradient of tree sizes. Constant tensile stress was found in species that rely on bark for the control of stem orientation in young stages. Other species had increasing compressive stress, associated with increasing density attributed to the development of sclereids. Compressive stress was also associated with low relative bark thickness. The relative thickness of bark decreased with size in all species, suggesting that a reorientation mechanism based on bark progressively performs less well as the tree grows. However, greater relative thickness was observed in species with more tensile stress, thereby evidencing that this reduction in performance is mitigated in species that rely on bark for reorientation.

Application of resistance drilling to genetic studies of growth, wood basic density and bark thickness in Eucalyptus globulus

2020 ◽  
Vol 83 (3) ◽  
pp. 172-179
Author(s):  
H. Nickolas ◽  
D. Williams ◽  
G. Downes ◽  
P. A. Harrison ◽  
R. E. Vaillancourt ◽  
...  
Keyword(s):  
Eucalyptus Globulus ◽  
Basic Density ◽  
Bark Thickness ◽  
Genetic Studies ◽  
Wood Basic Density ◽  
Resistance Drilling

Bark Thickness and Bark Volume in Southwestern Oregon Douglas-Fir

1990 ◽  
Vol 5 (1) ◽  
pp. 5-8 ◽  
Author(s):  
Douglas A. Maguire ◽  
David W. Hann
Keyword(s):  
Pseudotsuga Menziesii ◽  
Douglas Fir ◽  
Bark Thickness ◽  
Breast Height ◽  
Taper Equation ◽  
Taper Equations ◽  
Height Predictions

Abstract A segmented polynomial taper equation for southwestern Oregon Douglas-fir (Pseudotsuga menziesii) predicts double bark thickness (dbt) at any point above breast height. Below breast height predictions assume conformity to a neiloid frustrum. The equations facilitate estimation of inside bark diameter (dib) given outside bark (dob) measurements. Bark volume and bark biomass can also be estimated when supplemented with existing dib taper equations developed for southwestern Oregon. West J. Appl. For. 5(1):5-8.

scholarly journals VARIAÇÃO LONGITUDINAL E EFEITO DO ESPAÇAMENTO NA MASSA ESPECÍFICA BÁSICA DA MADEIRA DE Mimosa scabrella E Ateleia glazioveana

FLORESTA ◽  
2013 ◽  
Vol 43 (2) ◽  
pp. 327 ◽  
Author(s):  
Elder Eloy ◽  
Braulio Otomar Caron ◽  
Rômulo Trevisan ◽  
Denise Schmidt ◽  
Magda Lea Bolzan Zanon ◽  
...  
Keyword(s):  
Block Design ◽  
Wood Quality ◽  
Basic Density ◽  
Technological Characteristic ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Living Space ◽  
Randomized Complete Block Design ◽  
Axial Variation ◽  
Set Up

 Este trabalho teve como objetivo avaliar a variação longitudinal e o efeito do espaçamento de plantio na massa específica básica das árvores de Mimosa scabrella Benth e Ateleia glazioveana Baill, aos 36 meses de idade. Analisou-se um experimento instalado em delineamento de blocos completos casualizados, com três repetições. Os tratamentos foram definidos em função dos espaçamentos (2,0x1,0 m, 2,0x1,5 m, 3,0x1,0 m e 3,0x1,5 m). Foram avaliadas 72 árvores, sendo essas medidas e cubadas pelo método de Smalian. Em seguida, foram retirados discos nas posições do tronco: 0,10 m (base), 1,30 m do solo (DAP – Diâmetro a Altura do Peito), 25%, 50% e 75% da altura total da árvore, para determinação da massa específica básica. A massa específica básica em árvores de Mimosa scabrella apresentou um decréscimo até a região do DAP, seguido de acréscimo, sem tendência de estabilização com a altura. A Ateleia glazioveana apresentou uma tendência de decréscimo no sentido base-topo das árvores. Os espaçamentos influenciaram a variação da massa específica básica em árvores de Mimosa scabrella e Ateleia glazioveana, não sendo verificada uma variação sistemática positiva ou negativa em relação ao espaço vital proporcionado.Palavras-chave:  Variação axial; característica tecnológica da madeira; qualidade da madeira; espaçamento de plantio. AbstractLongitudinal variation and effect of spacing on basic density wood of Mimosa scabrella and Ateleia glazioveana. This study aimed to evaluate the variation in length and effect of spacing of the basic density of Mimosa scabrella Benth e Ateleia glazioveana Baill, trees with 36 months of age. We analyzed an experiment set up in randomized complete block design with three replications. The treatments were defined by the spacing (2.0x1.0 m, 2.0x1.5 m, 3.0x1.0 m, 3.0x1.5 m). 72 trees were evaluated, and these measures and scaled by the method of Smalian. Then, the disks were removed from the trunk positions: 0.10 m (base), 1.30 m (DAP - diameter at breast height), 25%, 50% and 75% of the total height of the tree, determining the basic density. The basic density in trees of Mimosa scabrella showed a decrease to the region of the DAP, followed by addition, without a tendency to stabilize with time. The Ateleia glazioveana showed a decreasing trend towards bottom-up tree. The spacing influenced the variation of basic density in trees of Mimosa scabrella e Ateleia glazioveana not been verified a systematic positive or negative trend in relation to the living space provided. Keywords: Axial variation; technological characteristic of wood; wood quality; planting space.

Sign in / Sign up

Export Citation Format

Share Document