A geometrical tree volume model based on the location of the centre of gravity of the bole

1982 ◽  
Vol 12 (2) ◽  
pp. 215-221 ◽  
Author(s):  
Robert R. Forslund
Keyword(s):  
Volume Estimation ◽  
Diameter Measurement ◽  
Stem Form ◽  
Total Height ◽  
Volume Model ◽  
Breast Height ◽  
Centre Of Gravity ◽  
Geometrical Form ◽  
Volume Equation ◽  
Diameter Outside Bark

A tree bole model describing a geometrical form in between a paraboloid and cone "paracone" has been developed. The model is based on empirical evidence that the average centre of gravity of aspen (Populustremuloides Michx.) boles without branches lies at 3/10 of the bole height from its base. Outside bark bole volume, V (cubic decimetres), can therefore be estimated nondestructively from the total height, H (metres), and the diameter outside bark, dK (centimetres), measured at a relative height, K, as follows:[Formula: see text]Based on a sample of 70 aspen stems, this equation estimates individual bole volume from total bole length or height and from a single diameter measurement, either at the 3/10 position or at the breast-height position, as accurately as Smalian's formula using seven diameter measurements. Based on the sample, the 3/10 position should be chosen over breast height wherever breast height lies below 20 or above 60% of the total height. It is important that care be taken in the measurement of the diameter due to the sensitivity of the volume equation to diameter variation. In addition to volume estimation, the paracone model provides a comparison profile around which stem form variation within and among species may be observed.

Application of a geometrical volume equation to species with different bole forms

1986 ◽  
Vol 16 (2) ◽  
pp. 311-314 ◽  
Author(s):  
G. B. MacDonald ◽  
R. R. Forslund
Keyword(s):  
Diameter Measurement ◽  
Stem Analysis ◽  
Individual Tree ◽  
Breast Height ◽  
Centre Of Gravity ◽  
Variable Equation ◽  
Input Variables ◽  
Volume Equation ◽  
Volume Estimates ◽  
Geometrical Equation

Stem analysis of 20 Abiesbalsamea (L.) Mill., 68 Piceamariana (Mill.) B.S.P., 19 Piceaglauca (Moench) Voss, 31 Populustremuloides Michx., and 37 Betulapapyrifera Marsh. revealed form variation between species. A volume equation based on the paracone (a geometrical solid midway between a paraboloid and a cone) estimated individual tree volume within 10% of the true volume (at the 95% confidence level) for all species. The input variables required were total height and diameter at a relative height of 0.2 for Betulapapyrifera and 0.3 for the other four species. If breast-height diameter was used, the effect of form variation on the accuracy of volume prediction was more pronounced. In this case, the geometrical equation modified for each species according to the average centre of gravity provided more consistently accurate volume estimates than either the paracone equation or Honer's transformed variable equation. For all species, the diameter measurement position was more critical than the version of the geometrical equation selected.

Integrated Systems for the Estimation of Tree Taper and Volume

1973 ◽  
Vol 3 (1) ◽  
pp. 90-94 ◽  
Author(s):  
J. P. Demaerschalk
Keyword(s):  
Integrated Systems ◽  
Total Height ◽  
Breast Height ◽  
Taper Equations ◽  
Diameter Outside Bark ◽  
Volume Equations

The desirability and the advantages of deriving taper equations from existing volume equations are discussed. It is demonstrated that the most common types of volume equations can be converted to compatible taper equations. These mathematical stem profile expressions yield tree volumes for any desired stump height and top diameter outside bark from inputs of diameter breast height outside bark and total height.

A simple volume estimation system and its application to three coniferous species

1994 ◽  
Vol 24 (6) ◽  
pp. 1289-1294 ◽  
Author(s):  
Kazukiyo Yamamoto
Keyword(s):  
Prediction Error ◽  
Volume Estimation ◽  
Stem Volume ◽  
Coniferous Species ◽  
Breast Height ◽  
Sample Data ◽  
Estimation System ◽  
Volume Equation ◽  
Using Data ◽  
Volume Equations

A simple system for the estimation of stem volume is presented based on the compatible stem profile and volume equations. This system can directly predict the stem volume above breast height from measurements of stem diameter at breast height and at an another point along the upper stem, and does not require any sample data for determining a parameter of volume equation. In comparison with the prediction accuracy of existing volume equations from the literature, using data from Cryptomeriajaponica D. Don, Chamaecyparisobtsusa Endl., and Pseudotsugamenziesii (Mirb.) Franco, this system has the advantage of reducing prediction error.

An investigation of product form

1984 ◽  
Vol 14 (6) ◽  
pp. 768-774 ◽  
Author(s):  
P. Roebbelen ◽  
V. G. Smith
Keyword(s):  
Black Spruce ◽  
Jack Pine ◽  
Small Sample ◽  
Red Pine ◽  
Product Form ◽  
Regression Equations ◽  
White Pine ◽  
Total Height ◽  
Breast Height ◽  
Diameter Outside Bark

Product form (P) of a tree has been defined as the product of diameter-outside-bark at midheight above breast height (d) and total height (H) (P = d × H). It is used along with diameter breast height (D) in product form volume equations (VPF = f(P,D)) for estimating individual tree volumes. It is hypothesized that for each coniferous species, there exists some optimal height at which a diameter measurement can be taken and used in a product form term to estimate the inside-bark volume with minimum error. Regression equations and simpler expressions of the form V = D2 × H × F were developed for red pine (Pinusresinosa Ait.), white pine (Pinusstrobus L.), jack pine (Pinusbanksiana Lamb.), and black spruce (Piceamariana (Mill.) B.S.P.) using six upper diameter locations. The optimal location of the upper diameter was found to be 50% of the total height for red pine and white pine and 47% of total height for jack pine and black spruce. Product form is redefined as P = d* × H where d* = diameter-outside-bark at that average relative height on the tree where d* = (2 × V)/(D × H) as determined from a small sample of scaled trees, for each species and H = total height of tree.

Comparison of relative accuracy and time requirement between the caliper, the diameter tape and an electronic tree measuring fork

1995 ◽  
Vol 71 (2) ◽  
pp. 197-200 ◽  
Author(s):  
Jean-Marie Binot ◽  
David Pothier ◽  
Jeannot Lebel
Keyword(s):  
Key Words ◽  
Data Entry ◽  
Pinus Strobus ◽  
Relative Accuracy ◽  
Diameter Measurement ◽  
Time Requirement ◽  
White Pine ◽  
Breast Height ◽  
Time Required ◽  
Diameter Outside Bark

This study compares the relative accuracy of diameters measured with the caliper, the diameter tape, and the electronic tree measuring fork (ETMF) Tally BoyMC with and without reflector. The time required for the measure and the data entry of diameters to computer for each instrument was also evaluated. Significant differences in mean DBH (diameter outside bark at breast height — 1.3 m above ground) generally occurred among instruments. Nevertheless, even if these differences were significant, they were less than 1 cm for five of the six species tested. For white pine (Pinus strobus L.), however, the use of the ETMF without reflector led to an important overestimation of the DBH in comparison to the caliper, the diameter tape and the ETMF with reflector. The typical fissured bark observed on white pines could probably explain that overestimation. For all species, the addition of the reflector to the ETMF decreased the differences among instruments. The measures taken with the diameter tape were slightly larger than those made with the caliper. In comparison to the diameter tape and the caliper, the ETMF reduced the time required for date collection from 35 to 45%. Key words: diameter measurement, timber inventory

scholarly journals Determination of lime tree (Tilia begonifolia Stev.) stems form based on quantitative parameters (Study area: Shafaroud forests of Guilan province, Iran)

2014 ◽  
Vol 56 (4) ◽  
pp. 165-170 ◽  
Author(s):  
Mohammad Rasoul Nazari Sendi ◽  
Iraj Hassanzad Navroodi ◽  
Hassan Poorbabaei ◽  
Mohammad Sheikhkanlu Milan ◽  
Behzad Bakhshandeh
Keyword(s):  
Form Factor ◽  
Coefficient Of Determination ◽  
Stem Volume ◽  
Stem Height ◽  
Stem Form ◽  
Diameter At Breast Height ◽  
Total Height ◽  
Breast Height ◽  
Lime Tree ◽  
Guilan Province

Abstract The lime tree is one of the rare and valuable species that found in the Hyrcanian moist forests with economic as well as ecological value. Identification of the quantitative and qualitative features of this species is important. In order to investigate the stem form of this species in the Shafaroud forests of Guilan Province, 141 lime trees in 39 plots were analyzed during the four stages of small pole, pole, saw-timber, and maturity. In each plot, stem-diameter at different heights was measured by using the Spiegel Relaskop. Measurements and analyses included diameter at breast height( d.b.h.) and total height. Same parameters was calculated: stem form factor based on diameter, stem form factor based on volume, form quotient, slenderness factor, ratio of stem height to total height, ratio of stem volume to total volume, correlation, and coefficient of determination to describe stem form factor. The results showed that the average stem form factor based on diameter was 0.554. The average stem form factor based on volume was 0.576, average form quotient was 2.32 and slenderness factor was 35.04%. The average ratio of stem height to total height was 82.45. In addition the results indicated a strong relationship between diameter at breast height and trunk coefficient. The ratio of stem volume to total volume revealed that 64.44 of lime volume is located in the bottom half of the trunk. The value of the parameters described here is towards a better description of stand characteristics. Obtained results indicating stability for natural lime tree in Iran.

Variance reduction in Ueno's method and cylinder sampling for forest volume estimation

1995 ◽  
Vol 25 (11) ◽  
pp. 1783-1794 ◽  
Author(s):  
Thomas B. Lynch
Keyword(s):  
Computer Simulation ◽  
Variance Reduction ◽  
Volume Estimation ◽  
Critical Height ◽  
Volume Estimate ◽  
Individual Tree ◽  
Stand Volume ◽  
Reduction Techniques ◽  
Antithetic Variates ◽  
Volume Equation

Three basic techniques are proposed for reducing the variance of the stand volume estimate provided by cylinder sampling and Ueno's method. Ueno's method is based on critical height sampling but does not require measurement of critical heights. Instead, a count of trees whose critical heights are less than randomly generated heights is used to estimate stand volume. Cylinder sampling selects sample trees for which randomly generated heights fall within cylinders formed by tree heights and point sampling plot sizes. The methods proposed here for variance reduction in cylinder sampling and Ueno's method are antithetic variates, importance sampling, and control variates. Cylinder sampling without variance reduction was the most efficient of 12 methods compared in computer simulation that used estimated measurement times. However, cylinder sampling requires knowledge of a combined variable individual tree volume equation. Of the three variance reduction techniques applied to Ueno's method, antithetic variates performed best in computer simulation.

scholarly journals Taper Equations for Five Major Commercial Tree Species in Manitoba, Canada

2007 ◽  
Vol 22 (3) ◽  
pp. 163-170 ◽  
Author(s):  
Ryan J. Klos ◽  
G. Geoff Wang ◽  
Qing-Lai Dang ◽  
Ed W. East
Keyword(s):  
Populus Tremuloides ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
White Spruce ◽  
Jack Pine ◽  
Volume Estimation ◽  
Trembling Aspen ◽  
Stem Form ◽  
Taper Equation ◽  
Taper Equations

Abstract Kozak's variable exponent taper equation was fitted for balsam poplar (Populus balsamifera L.), trembling aspen (Populus tremuloides Michx.), white spruce (Picea glauca [Moench] Voss), black spruce (Picea mariana [Mill.] B.S.P.), and jack pine (Pinus banksiana Lamb.) in Manitoba. Stem taper variability between two ecozones (i.e., Boreal Shield and Boreal Plains) were tested using the F-test. Regional differences were observed for trembling aspen, white spruce, and jack pine, and for those species, separate ecozone-specific taper equations were developed. However, the gross total volume estimates using the ecozone-specific equations were different from those of the provincial equations by only 2 percent. Although the regional difference in stem form was marginal within a province, a difference of approximately 7 percent of gross total volume estimation was found when our provincial taper equations were compared with those developed in Alberta and Saskatchewan. These results suggest that stem form variation increases with spatial scale and that a single taper equation for each species may be sufficient for each province.

Evaluation of relative density, diameter growth, and stem form in a red spruce (Picearubens) stand 15 years after precommercial thinning

1992 ◽  
Vol 22 (2) ◽  
pp. 229-238 ◽  
Author(s):  
R. James Barbour ◽  
R.E. Bailey ◽  
Jean A. Cook
Keyword(s):  
Relative Density ◽  
Red Spruce ◽  
Stem Form ◽  
Eastern Canada ◽  
Precommercial Thinning ◽  
X Ray ◽  
Total Height ◽  
The Difference ◽  
And Control ◽  
Average Relative Density

Thirty red spruce (Picearubens Sarg.) trees were harvested from a precommercial thinning trial near St. Margaret's Bay, Nova Scotia. Total height was measured, and samples were removed from the following five stem heights: stump height, breast height, 25, 50, and 75% of total height. Relative density and growth rate were measured using X-ray densitometry, and taper was calculated for log and tree lengths. Growth rates were significantly greater on the treatment plot than on the control plot. No significant differences in relative density were found between trees from the treatment plot (2.4 × 2.4 m spacing) and trees from the unthinned control. The relative density of the treatment and control trees was also compared with the species average relative density for red spruce. No significant differences were found, except for the relative density at stump height in the after-treatment portion of the trees from the thinned plot. The difference was not considered great enough to cause a deterioration of the mechanical properties of lumber or the yield of pulp produced from this material. The taper factor was significantly different between the treatment and control plots, but the taper factor for the treatment trees was similar to that for the spruce resource currently being processed in eastern Canada.

Sign in / Sign up

Export Citation Format

Share Document