Relationships between the mean trees by basal area and by volume: reconciling form factors in the classic Bavarian yield and volume tables for Norway spruce

2014 ◽  
Vol 133 (5) ◽  
pp. 871-877 ◽  
Author(s):  
C. S. Eastaugh
Keyword(s):  
Norway Spruce ◽  
Form Factors ◽  
Basal Area ◽  
The Mean

Biomass estimates derived from sector subsampling of 360° spherical images

2021 ◽  
Author(s):  
Xiao Dai ◽  
Mark J Ducey ◽  
Haozhou Wang ◽  
Ting-Ru Yang ◽  
Yung-Han Hsu ◽  
...  
Keyword(s):  
Basal Area ◽  
Sampling Errors ◽  
Eastern Canada ◽  
Individual Tree ◽  
Inventory Costs ◽  
Standard Error Estimation ◽  
The Mean ◽  
Biomass Ratio ◽  
Spherical Images ◽  
Additional Level

Abstract Efficient subsampling designs reduce forest inventory costs by focusing sampling efforts on more variable forest attributes. Sector subsampling is an efficient and accurate alternative to big basal area factor (big BAF) sampling to estimate the mean basal area to biomass ratio. In this study, we apply sector subsampling of spherical images to estimate aboveground biomass and compare our image-based estimates with field data collected from three early spacing trials on western Newfoundland Island in eastern Canada. The results show that sector subsampling of spherical images produced increased sampling errors of 0.3–3.4 per cent with only about 60 trees measured across 30 spherical images compared with about 4000 trees measured in the field. Photo-derived basal area was underestimated because of occluded trees; however, we implemented an additional level of subsampling, collecting field-based basal area counts, to correct for bias due to occluded trees. We applied Bruce’s formula for standard error estimation to our three-level hierarchical subsampling scheme and showed that Bruce’s formula is generalizable to any dimension of hierarchical subsampling. Spherical images are easily and quickly captured in the field using a consumer-grade 360° camera and sector subsampling, including all individual tree measurements, were obtained using a custom-developed python software package. The system is an efficient and accurate photo-based alternative to field-based big BAF subsampling.

Carbon Stocks of Linear Category of Trees Out Side Forest in Anantapuramu District, Andhra Pradesh, India

2016 ◽  
Vol 39 (4) ◽  
pp. 303-308
Author(s):  
G. Kavitha ◽  
S. Salamma ◽  
M. Ramesh ◽  
Mudavath Naik ◽  
M. Kumar ◽  
...  
Keyword(s):  
Basal Area ◽  
Carbon Stocks ◽  
Linear Structures ◽  
Carbon Sequestration Potential ◽  
Sequestration Potential ◽  
The Mean ◽  
Angiosperm Species ◽  
Linear Category ◽  
Total Tree ◽  
Trees Outside Forest

In the present study, carbon stocks of linear structures of trees outside forest in Anantapuramu district was estimated through sampling of 344 (0.1 ha) plots. A total of 4229 tree individuals belonging to 66 angiosperm species were enumerated in the sampled plots. The mean tree density is 122.8per ha; mean diameter at breast height 4.04 m; mean basal area 15.43 m2 ha-1.Mean volume of trees with >10 cm diameter is 15.50 m3 ha-1; mean total tree biomass is 120.81 tons ha-1.The mean carbon stock is 57.385 tons ha-1 and extrapolated biomass and carbon content for linear structures are 0.176 Mt and 0.083 Mt respectively. The carbon sequestration potential of trees outside forests of Anantapuramu district is estimated at 0.304 Mt.

Inoptimality losses in forest management decisions caused by errors in an inventory based on airborne laser scanning and aerial photographs

2010 ◽  
Vol 40 (12) ◽  
pp. 2427-2438 ◽  
Author(s):  
Md. Nurul Islam ◽  
Mikko Kurttila ◽  
Lauri Mehtätalo ◽  
Timo Pukkala
Keyword(s):  
Input Data ◽  
Laser Scanning ◽  
Basal Area ◽  
Airborne Laser Scanning ◽  
Aerial Photographs ◽  
Stand Age ◽  
Inventory Data ◽  
Airborne Laser ◽  
Mean Diameter ◽  
The Mean

Errors in inventory data may lead to inoptimal decisions that ultimately result in financial losses for forest owners. We estimated the expected monetary losses resulting from data errors that are similar to errors in laser-based forest inventory. The mean loss was estimated for 67 stands by simulating 100 realizations of inventory data for each stand with errors that mimic those in airborne laser scanning (ALS) based inventory. These realizations were used as input data in stand management optimization, which maximized the present value of all future net incomes (NPV). The inoptimality loss was calculated as the difference between the NPV of the optimal solution and the true NPV of the solution obtained with erroneous input data. The results showed that the mean loss exceeded €300·ha–1 (US$425·ha–1) in 84% of the stands. On average, the losses increased with decreasing stand age and mean diameter. Furthermore, increasing errors in the basal area weighted mean diameter and basal area of spruce were found to significantly increase the loss. It has been discussed that improvements in the accuracy of ALS-based inventory could be financially justified.

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.

scholarly journals Effects of heavy thinnings on the increment and selection of trees for tending in Norway spruce monoculture in natural hazard conditions

2017 ◽  
pp. 31-54
Author(s):  
Martin Bobinac ◽  
Sinisa Andrasev ◽  
Andrijana Bauer-Zivkovic ◽  
Nikola Susic
Keyword(s):  
Norway Spruce ◽  
Growth Stage ◽  
Natural Hazard ◽  
Basal Area ◽  
Growth Potential ◽  
Stand Age ◽  
Diameter Increment ◽  
Volume Increment ◽  
Selection Of ◽  
Area And Volume

The paper studies the effects of two heavy selection thinnings on the increment of Norway spruce trees exposed to ice and snow breaks in eastern Serbia. In a thinning that was carried out at 32 years of age, 556 candidates per hectare were selected for tending, and at the age of 40, of the initial candidates, 311 trees per hectare (55.9%) were selected as future trees. In all trees at 41-50 age period, diameter increment was higher by 31%, basal area increment by 64% and volume increment by 67% compared to 32-40 age period. The collective of indifferent trees is significantly falling behind compared to future trees in terms of increment values in both observed periods. However, the value of diameter, basal area and volume increments, of the collective of "comparable" indifferent trees are lower in comparison to the values of increments of future trees by 10-15% in the 32-40 age period, and by 15-21% in the 41-50 age period and there are no significant differences. The results show that heavy selective thinnings, initially directed at a larger number of candidates for tending at stand age that does not differ much from the period of carrying out first "commercial" thinnings, improve the growth potential of future and indifferent trees, where it is rational to do the tree replacement for the final crop in "susceptible" growth stage to snow and ice breaks.

CURRENTS, SPIN DENSITIES AND MEAN-FIELD FORM FACTORS IN ROTATING NUCLEI: A SEMI-CLASSICAL APPROACH

2004 ◽  
Vol 13 (01) ◽  
pp. 225-233 ◽  
Author(s):  
J. BARTEL ◽  
K. BENCHEIKH ◽  
P. QUENTIN
Keyword(s):  
Mean Field ◽  
Form Factors ◽  
Spin Vector ◽  
Self Consistent ◽  
Field Form ◽  
Local Densities ◽  
The Mean ◽  
Self Consistency ◽  
Spin Densities ◽  
Rotating Nuclei

We present self-consistent semi-classical local densities characterising the structure of rotating nuclei. A particular emphasis is put on those densities which are generated by the breaking of time-reversal symmetry through the cranking piece of the Routhian, namely the current density and the spin vector density. Our approach which is based on the Extended-Thomas-Fermi method goes beyond the Inglis cranking approach and contains naturally the Thouless-Valatin self-consistency terms expressing the response of the mean field to the time-odd part of the density matrix.

Site Index Curves for Norway Spruce in Southern Ontario1

1989 ◽  
Vol 6 (1) ◽  
pp. 23-26 ◽  
Author(s):  
Andrew M. Gordon ◽  
Peter A. Williams ◽  
Edward P. Taylor
Keyword(s):  
Norway Spruce ◽  
Soil Texture ◽  
Sandy Soils ◽  
Site Index ◽  
Height Growth ◽  
Stem Analysis ◽  
Mean Values ◽  
Breast Height ◽  
Drainage Class ◽  
The Mean

Abstract Four dominant or codominant Norway spruce trees from each of 55 sites were destructively sampled and the annual height growth determined by stem analysis. The sampled sites were stratified by soil textural class (coarse, medium, and fine) and depth to distinct mottling (0-16, 16-40, and 40 in.). Two sets of an-amorphic site index curves were constructed using a total age of 30 years (SI30), and breast height age of 25 years (SIBH25) as base ages. The mean SI30 from Ontario (53 ft) was found to be 17.8% higher than the mean values published from Vermont (45 ft) and currently used in Ontario. SIBH25 values had a range of 34.6 to 74.8 ft with a mean of 55.3 ft. Analysis of variance showed significant differences in SIBH25 due to soil texture and drainage class, and in years to breast height (BH) due to drainage class. SIBH25 was highest on sites with loamy soils and distinct mottling at 16-40 in. It took an average of 6.5 years for seedlings to reach BH with a range of 3 to 12 years. Years to BH was lowest on sites with sandy soils and those with distinct mottling below 40 in. North. J. Appl. For. 6(1):23-26, March 1989.

scholarly journals Breeding value of Norway spruce (Picea abies [L.] Karst.)

2012 ◽  
Vol 50 (No. 1) ◽  
pp. 17-23
Author(s):  
Rożkowski KR
Keyword(s):  
Survival Rate ◽  
Norway Spruce ◽  
Growth Traits ◽  
Block Design ◽  
Basal Area ◽  
Tree Height ◽  
Breeding Value ◽  
Cross Sectional ◽  
Qualitative Traits ◽  
Crown Density

This is the first report on measurements and observations of an experimental plot of 35-year-old Norway spruce, established in 1970 by the Institute of Dendrology at K&oacute;rnik, where progenies of 22 plustrees from the Kłodzko Forest District were planted. The experiment was established in an incomplete block design of 20 families with 3 replications. Survival rate and growth traits determining productivity (plant height or basal area &ndash; stem cross-sectional area at breast height per 1&nbsp;ha) were assessed in several years, and qualitative traits (trunk straightness; degree of natural pruning; thickness, length and angle of branches; crown density; presence of galls caused by the aphids Adelges laricis Vall. and Sacchiphantes viridis Ratz.) were evaluated once in 2001. Analysis of variance revealed significant differences between the half-sib families in survival rate and productivity but no significant differences in qualitative traits. Statistically significant positive correlations were found between trunk straightness at the age of<br />&nbsp;36 years and height of 2-year-old seedlings in the nursery, and between the degree of natural pruning at the age of 36 years and both tree height at the age of 9 years and basal area at the age of 13 years.

Study on the Motion Response of Buoy in Sea Condition

2013 ◽  
Vol 712-715 ◽  
pp. 1335-1338
Author(s):  
Yan Gang Wang ◽  
Xing Hua Tong ◽  
Lin Sen Zhu ◽  
Yong Liu
Keyword(s):  
Basal Area ◽  
The Other ◽  
Mooring Line ◽  
Wave Power ◽  
Loading Conditions ◽  
Power Devices ◽  
Motion Response ◽  
Axis Direction ◽  
Floating System ◽  
The Mean

In the research of buoy wave power devices, earlier studies have indicated that the vertical cylindrical can absorb the most power from wave by comparing the loading conditions of several buoys (e.g.cuboid, vertical cylindrical, horizontal cylindrical, sphere, and so on) using the Froude-Krylov theory. However, it is not argued the motion response of buoys with the same basal area and the different basal shapes. In this paper, buoys with the same basal area and the different basal shapes are investigated by the mean of simulation. There are two modes for the floating system, one is with mooring line and the other is without. In both cases, the motions in horizontal (x axis) and vertical (z axis) direction will be studied.

scholarly journals Production impacts of forest tree breeding on an example of Norway spruce

2010 ◽  
Vol 56 (No. 8) ◽  
pp. 348-352
Author(s):  
J. Kobliha ◽  
M. Slávik ◽  
V. Hynek ◽  
J. Klápště ◽  
J. Stejskal
Keyword(s):  
Norway Spruce ◽  
Economic Efficiency ◽  
Growth Parameters ◽  
Tree Breeding ◽  
Forest Tree ◽  
Stem Volume ◽  
Forest Tree Breeding ◽  
The Mean

The present paper evaluates the height, diameter and stem volume of parental tree progenies. These Norway spruce progenies are compared with the control estimated from tables. The control was overperformed in all measured growth parameters. Heights of selected spruce progenies at the age of 26 years ranged from 9.2 m (K10) to 10.7 m (K2). The control height was 6.4 m. In the evaluation of diameters, progeny K4 showed the best mean dbh (13.7 cm) while the progeny K17 was rated as the thinnest (10.5 cm). We compared these data with the control diameter of 6.5 cm. The mean volumes of selected material varied from 0.097 m<sup>3 </sup>(K9) to 0.047 m<sup>3 </sup>(K17) while the kontrol presented 0.0172 m<sup>3</sup>. Keywords: economic efficiency; forest tree breeding; growth; Norway spruce; production

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