scholarly journals ESTIMATION OF PRODUCTIVITY AND PRIME COST OF LOGSET 5HP GT HARVESTER IN THINNING

2018 ◽  
Author(s):  
Guna PETAJA ◽  
Aldis BUTLERS ◽  
Modris OKMANIS ◽  
Agris ZIMELIS
Keyword(s):  
Production Cost ◽  
Stem Volume ◽  
Time Study ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Prime Cost ◽  
Commercial Thinning ◽  
Study Results ◽  
Work Hour ◽  
Increase Production Cost

Productivity of a harvester significantly affects costs of mechanized felling, which in turn determines, if commercial thinning will be profitable. The objective of this study is to estimate productivity and prime cost of Logset 5HP GT harvester with increased boom length (11 m), equipped with the TH45 felling head, in thinning. Trials are conducted in Latvia, eastern Vidzeme, in coniferous stands. To evaluate productivity of Logset 5HP GT, a time study was carried out. Influence of small trees (diameter at breast height < 8 cm) on productivity and harvesting cost was also determined. During the trials 2379 trees are harvested with the total stem volume of 400 m3. The diameter at breast height of an average harvested tree is 14 cm and volume of a stem – 0.171 m3. Duration of time study is 33.5 h. Obtained productivity rates of Logset 5HP GT are compared with those of John Deere 1070 D harvester. According to the study results average productivity of Logset 5HP GT harvester in thinning of coniferous stands is 13.85 m3 per productive work hour. Prime cost of harvesting of the Logset 5HP GT in thinning is 8.02 € m-3. Increased boom length allows to decrease the total time spent for driving in a stand by 71%. Harvesting of small trees reduces productivity by 6.9% and increase production cost by 2.1% in the experimental stands. Difference between productivity of Logset 5HP GT and John Deere 1070 D in similar conditions is statistically insignificant.

scholarly journals Estimation of Genetic Parameters and Wood Yield Selection Index in a Clonal Trial of Korean Pine (Pinus koraiensis) in Northeastern China

2021 ◽  
Vol 13 (8) ◽  
pp. 4167
Author(s):  
David Kombi Kaviriri ◽  
Huan-Zhen Liu ◽  
Xi-Yang Zhao
Keyword(s):  
Selection Index ◽  
Tree Height ◽  
Stem Volume ◽  
Korean Pine ◽  
Branch Number ◽  
Basal Diameter ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Stem Straightness ◽  
Clonal Trial

In order to determine suitable traits for selecting high-wood-yield Korean pine materials, eleven morphological characteristics (tree height, basal diameter, diameter at breast height, diameter at 3 meter height, stem straightness degree, crown breadth, crown height, branch angle, branch number per node, bark thickness, and stem volume) were investigated in a 38-year-old Korean pine clonal trial at Naozhi orchard. A statistical approach combining variance and regression analysis was used to extract appropriate traits for selecting elite clones. Results of variance analysis showed significant difference in variance sources in most of the traits, except for the stem straightness degree, which had a p-value of 0.94. Moderate to high coefficients of variation and clonal repeatability ranged from 10.73% to 35.45% and from 0.06% to 0.78%, respectively. Strong significant correlations on the phenotypic and genotypic levels were observed between the straightness traits and tree volume, but crown breadth was weakly correlated to the volume. Four principal components retaining up to 80% of the total variation were extracted, and stem volume, basal diameter, diameter at breast height, diameter at 3 meter height, tree height, and crown height displayed high correlation to these components (r ranged from 0.76 to 0.98). Based on the Type III sum of squares, tree height, diameter at breast height, and branch number showed significant information to explain the clonal variability based on stem volume. Using the extracted characteristics as the selection index, six clones (PK105, PK59, PK104, PK36, PK28, and K101) displayed the highest Qi values, with a selection rate of 5% corresponding to the genetic gain of 42.96% in stem volume. This study provides beneficial information for the selection of multiple traits for genetically improved genotypes of Korean pine.

scholarly journals Linear Regression Model to Identify the Factors Associated with Carbon Stock in Chure Forest of Nepal

Scientifica ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Ira Sharma ◽  
Sampurna Kakchapati
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Linear Regression Model ◽  
Carbon Stock ◽  
Multiple Linear Regression Model ◽  
Greenhouse Gas Mitigation ◽  
Stem Volume ◽  
Diameter At Breast Height ◽  
Factors Associated ◽  
Breast Height

Use of woody plants for greenhouse gas mitigation has led to the demand for rapid cost-effective estimation of forest carbon stock and related factors. This study aims to assess the factors associated with carbon stock in Chure forest of Nepal. The data were obtained from Department of Forest Research and Survey (DFRS) of Nepal. A multiple linear regression model and then sum contrasts were used to observe the association between variables such as stem volume, diameter at breast height, altitude, districts, number of trees per plot, and ownership of the forest. 95% confidence interval (CI) plots were drawn for comparing the adjusted carbon stocks with each of the factors and with the overall carbon stock. The linear regression showed a good fit of the model (adjusted R2 = 83.75%) with the results that the stem volume (sv), diameter at breast height (dbh), and the number of trees per plot showed statistically significant (p value ≤ 0.05) positive association with carbon stock. The highest carbon stock was associated with sv more than 199 m3/ha, average dbh more than 43.3 cm/plot, and number of trees more than 20/plot, whereas the altitude, geographical location, and ownership had no statistical associations at all. The results can be of use to the government for enhancing carbon stock in Chure that supports both natural resource conservation and United Nations-Reducing Emission from Deforestation and Forest Degradation program to mitigate carbon emission issues.

scholarly journals Comparison of Volumes Estimated from Breast Height and Stump Diameters: Application to Tectona grandis Data

2020 ◽  
Vol 66 (5) ◽  
pp. 551-555
Author(s):  
Onyekachi Chukwu ◽  
Friday N Ogana ◽  
Juliet U Nwatu
Keyword(s):  
Growth Model ◽  
Tectona Grandis ◽  
Information Criterion ◽  
Volume Estimation ◽  
Stem Volume ◽  
Model Assessment ◽  
Significance Level ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Stump Diameter

Abstract Models estimating tree volume from stump diameter are important forest-management tools when volume estimation is needed postharvest, and dbh values are unavailable, for example the incidence of timber trespass. However, the use of stump diameter as the only independent variable for predicting tree volume has been limited. Therefore, in this article, stump diameter was used to estimate stem volume of Tectona grandis Linn. f, and this was compared with volume estimated from diameter at breast height. Five functions were considered each for the two stem diameters: simple linear, semilogarithmic, zero-intercept, power, and growth. Model assessment was based on least values of the root mean square error and Akaike information criterion. The results showed that the growth model had the best overall performance for both sets of volume models. A paired-sample t-test was used to compare volume estimated by stump diameter and volume estimated by diameter at breast height at 5 percent significance level. The results showed that there were no significant differences (P = .087) between timber volumes estimated from both stem diameters. Therefore, both diameters can be used interchangeably for modeling tree volume.

scholarly journals An Evaluation of Selection for Volume Growth in Loblolly Pine

2008 ◽  
Vol 57 (1-6) ◽  
pp. 22-28 ◽  
Author(s):  
J. R. Sherrill ◽  
T. J. Mullin ◽  
B. P. Bullock ◽  
S. E. Mckeand ◽  
R. C. Purnell ◽  
...  
Keyword(s):  
Loblolly Pine ◽  
Selection Criterion ◽  
Direct Determination ◽  
Stem Volume ◽  
Bark Thickness ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Stem Taper ◽  
Selection For ◽  
Volume Estimates

Abstract Total inside-bark volume is the most important selection criterion for productivity in tree breeding programs in the Southeastern U.S. Tree breeders typically estimate total inside-bark volume based on outside-bark diameter at breast height and total height without accounting for stem taper or bark thickness. To make a direct determination of total inside- and outside-bark volume, a loblolly pine (Pinus taeda L.) open-pollinated family trial replicated with cultural treatments of weed control and fertilization was measured. This direct measurement was compared to typical volume estimates. In this trial, approximately 40 individuals from each of 25 open-pollinated first- and second-generation families were destructively sampled in the 13th growing season. Selection for volume using a combined-variable (diameter2 * height) equation was found to be highly effective for making volume gain. There was a high correlation between estimated and directly-measured total inside-bark volumes (0.99). Bark thickness and stem taper had low importance for stem volume selection. There was a positive genetic correlation between bark thickness and diameter at breast height (0.66). This indicates that selection for larger diameters may produce individuals with thicker bark, which may eventually affect total inside-bark volume estimates.

scholarly journals Wedge prism as a tool for diameter and distance measurement

2008 ◽  
Vol 54 (No. 3) ◽  
pp. 121-124 ◽  
Author(s):  
L. Šálek ◽  
D. Zahradník
Keyword(s):  
Basal Area ◽  
Distance Measurement ◽  
Stem Volume ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Standing Trees ◽  
Wedge Prism ◽  
Non Destructive

The wedge prism, which is generally used for the measurement of basal area in diameter at breast height, is also a tool for the measurement of distance as well as for the measurement of diameters at a certain height of the stem, in the upper stem. Measurements using the wedge prism are based on the same principle as measurements using Bitterlich mirror relascope. This method is appropriate for non-destructive determination of stem volume. Moreover, the wedge prism can be used for the sorting of logs in standing trees when the small end of expectant assortment has to be known. As the wedge prism is a common tool for foresters, its usage seems to be larger than only the measurement of basal area.

scholarly journals Allometric relations between biomass and diameter at breast height and height of tree in natural forests at Me Linh Station for Biodiversity, Vinh Phuc Province, Vietnam

2018 ◽  
Vol 9 (5) ◽  
pp. 264-271
Author(s):  
Thi Thu Huong Dang ◽  
Huu Thu Do ◽  
Minh Quang Trinh ◽  
Hung Manh Nguyen ◽  
Thi Tuyet Xuan Bui ◽  
...  
Keyword(s):  
Carbon Sequestration ◽  
Tree Species ◽  
Allometric Equation ◽  
Stem Diameter ◽  
Total Biomass ◽  
Regression Equations ◽  
Natural Forests ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Study Results

Stem diameter at breast height (D1.3m) and tree height (H) are commonly used measures of tree growth. Based on correlation analysis between biomass of stem, branches and leaves and stem diameter and height of tree we can identify allometric equation for predicting biomass and carbon sequestration of the vegetation. This study was carried out in the natural forests of Me Linh Station for biodiversity to develop allometric equation between biomass and diameter at breast height and height of tree. The study results indicated that twenty tree species dominate in natural forests in Me Linh Station for Biodiversity and they were selected for sampling. Through the 80 established linear equation models for above and below –ground biomass (AGB and BGB), we found that the biomass of tree species in Me Linh Station for Biodiversity were closely correlated with the diameter factor (R>0.902) and not clearly correlated with the height (correlation coefficient = 0.5498, R2< 0.549). Four regression equations were established, including: Pstem = 25.3051*(D1.3m)0.4627 (R2 : 9.661); Pbranch = 12.1043*(D1.3m)0.5416 (R2 : 9.8); Pleaves = 9.446*(D1.3m)0.5976 (R2 : 0.9363); P total biomass of forest = 25.882*D1.725 with R2: 0.8561) for estimating biomass and carbon sequestration of natural forest at the research site. Đường kính ngang ngực (D1.3m) và chiều cao (H) cây là hai nhân tố thường được dùng để đánh giá sự phát triển của cây gỗ. Việc xây dựng các phương trình tương quan giữa sinh khối (SK) thân, cành, lá, sinh khối tầng cây gỗ, sinh khối của quần xã thực vật với đường kính và chiều cao cây góp phần rất lớn trong dự báo sinh khối và khả năng hấp thụ khí carbon của thảm thực vật. Kết quả nghiên cứu cho thấy 20 loài cây gỗ chiếm ưu thế trong rừng tự nhiên và chúng được chọn để thu mẫu. Mối tương quan giữa sinh khối với 2 nhân tố điều tra rừng là đường kính ngang ngực và chiều cao cây đã đươc kiểm tra thông qua 80 phương trình tương quan. Nhìn chung, sinh khối có tương quan chặt chẽ với nhân tố đường kính (hệ số tương quan R > 0,902), và không tương quan rõ với nhân tố chiều cao (R < 0,5498). Bốn phương trình tính sinh khối cho thảm rừng tại khu vực nghiên cứu đã được thiết lập: SKthân = 25,3051*(D1,3m)0,4627 (R2: 9,661); SKcành: 12,1043*(D1,3m)0,5416 (R2: 9,8); SKlá: 9,446*(D1,3m)0,5976 (R2: 0,9363) và SKtổng = 25,882*D1,725 with R2: 0,8561).

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.

scholarly journals Seemingly Unrelated Mixed-Effects Biomass Models for Black Locust in West Poland

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 380
Author(s):  
Karol Bronisz ◽  
Szymon Bijak ◽  
Rafał Wojtan ◽  
Robert Tomusiak ◽  
Agnieszka Bronisz ◽  
...  
Keyword(s):  
Black Locust ◽  
Random Effect ◽  
Tree Height ◽  
Cross Model ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Dependent Variables ◽  
Dry Biomass ◽  
Biomass Components ◽  
Independent Variable

Information about tree biomass is important not only in the assessment of wood resources but also in the process of preparing forest management plans, as well as for estimating carbon stocks and their flow in forest ecosystems. The study aimed to develop empirical models for determining the dry mass of the aboveground parts of black locust trees and their components (stem, branches, and leaves). The research was carried out based on data collected in 13 stands (a total of 38 sample trees) of black locust located in western Poland. The model system was developed based on multivariate mixed-effect models using two approaches. In the first approach, biomass components and tree height were defined as dependent variables, while diameter at breast height was used as an independent variable. In the second approach, biomass components and diameter at breast height were dependent variables and tree height was defined as the independent variable. Both approaches enable the fixed-effect and cross-model random-effect prediction of aboveground dry biomass components of black locust. Cross-model random-effect prediction was obtained using additional measurements of two extreme trees, defined as trees characterized by the smallest and largest diameter at breast height in sample plot. This type of prediction is more precise (root mean square error for stem dry biomass for both approaches equals 77.603 and 188.139, respectively) than that of fixed-effects prediction (root mean square error for stem dry biomass for both approaches equals 238.716 and 206.933, respectively). The use of height as an independent variable increases the possibility of the practical application of the proposed solutions using remote data sources.

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