scholarly journals ĐẶC ĐIỂM CẤU TRÚC VÀ SINH TRƯỞNG RỪNG TRỒNG KEO LƯỠI LIỀM (Acacia crassicarpa A.Cunn. ex Benth.) TẠI TỈNH BÌNH THUẬN

2020 ◽  
Vol 4 (2) ◽  
pp. 1940-1950
Author(s):  
Nguyễn Văn Việt ◽  
Phan Thị Thanh Thủy ◽  
Lê Châu Thành
Keyword(s):  
Growth Rate ◽  
Weibull Distribution ◽  
Tree Height ◽  
Water Source ◽  
Growth Function ◽  
Forest Plantation ◽  
Crown Diameter ◽  
Breast Height ◽  
Acacia Crassicarpa ◽  
Set Up

Trong những năm gần đây, Keo lưỡi liềm được đưa vào trồng trên các vùng cát ven biển tại Bình Thuận nhằm hạn chế tình trạng sa mạc hóa, duy trì nguồn nước ổn định, chặn đứng nạn cát bay, cát nhảy ở vùng này và thực tế cho thấy loài cây này đã sinh trưởng và phát triển tốt. Bài viết này công bố những kết quả nghiên cứu về cấu trúc và sinh trưởng của rừng trồng keo lưỡi liềm tại Bình Thuận. Nghiên cứu áp dụng phương pháp lập 60 ô tiêu chuẩn (otc) điển hình trên đối tượng rừng trồng keo lưỡi liềm tại Bình Thuận. Kết quả nghiên cứu cho thấy, phân bố số cây theo cỡ đường kính ngang ngực và đường kính tán có dạng một đỉnh lệch trái trong khi đó phân bố số cây theo chiều cao có dạng đỉnh lệch phải và được mô phỏng tốt bằng hàm Weibull. Quá trình sinh trưởng về đường kính thân (D1,3), chiều cao (Hvn), đường kính tán (Dt), thể tích (V) và trữ lượng (M) được mô tả rất tốt bằng hàm Schumacher. Các phương trình sinh trưởng như sau: ABSTRACT In recent years, Acacia crassicarpa A. Cunn.ex Benth. has been planted in the coastal sandy areas of Binh Thuan province to prevent desertification, maintain the water source, stop the flying sand, giving good results. The research results of the study presented the growth and the growth rate of the forest plantation of Acacia crassicarpa A. Cunn.ex Benth. We set up 60 particularly random sample plots on the Acacia crassicarpa plantation. The results showed that the distribution of diameter at breast height (N%/D1.3) and crown diameter (N%/Dt) were left skewed peak distributions while the distribution of tree height (N%/HVN) was a right skewed peak distribution and were well-simulated by Weibull distribution. The growth of Acacia crassicarpa plantation was modeled by Schumacher function, growth function as follows:

scholarly journals Contribution of some Acacia Species on Carbon Sequestration in Blue Nile State, Sudan

2021 ◽  
pp. 97-105
Keyword(s):  
Carbon Sequestration ◽  
Wood Density ◽  
Carbon Stock ◽  
Tree Height ◽  
Biomass Estimation ◽  
Expansion Factor ◽  
Wood Volume ◽  
Crown Diameter ◽  
Breast Height ◽  
Acacia Seyal

Background: The current challenge is to reduce the uncertainties in obtaining accurate and reliable data of carbon stock changes and emission factors essential for reporting national inventories. Improvements in above ground biomass estimation can also help account for changes in carbon stock in forest areas that may potentially participate in the Reducing emissions from deforestation and forest degradation and other initiatives. Current objectives for such estimates need a unified approach which can be measurable, reportable, and verifiable. This might result to a geographically referenced biomass density database for Sudanese forests that would reduce uncertainties in estimating forest aboveground biomass. The main objective: of this study is to assess potential of some selected forest variables for modeling carbon sequestration for Acacia seyal, vr. Seyal, Acacia seyal, vr. fistula, Acacia Senegal. The specific objectives include development of empirical allometric models for forest biomass estimation, estimation of carbon sequestration for these tree species, estimation of carbon sequestration per hectare and comparing the amount with that reported to the region. A total of 10 sample trees for biomass and carbon determination were selected for each of the three species from El Nour Natural Forest Reserve of the Blue Nile State, Sudan. Data of diameter at breast height, total tree height, tree crown diameter, crown height, and upper stem diameters were measured. Then sample trees were felled and sectioned to their components, and weighed. Subsamples were selected from each component for oven drying at 105 ˚C. Finally allometric models were developed and the aboveground dry weight (dwt) and carbon sequestered per hector were calculated. The results: presents biomass equations, biomass expansion factor and wood density that developed for the trees. In case of inventoried wood volume, corrections for biomass expansion factor and wood density value were done, and new values are suggested for use to convert wood volume to biomass estimates. The results also, indicate that diameter at breast height, crown diameter and tree height are good predictors for estimation of tree dwt and carbon stock. Conclusion: The developed allometric equations in this study gave better estimation of dwt than default value. The average carbon stock was found to be 22.57 t/ha.

scholarly journals Reproductive phenology of Uspí tree Couepia polyandra (Kunth) Rose (Chrysobalanaceae) in Campeche, Mexico

2020 ◽  
Vol 13 (10) ◽  
Author(s):  
Sol de Mayo A. Mejenes-López ◽  
Gustavo E. Mendoza-Arroyo ◽  
Manuel Marín-Quintero ◽  
Ricardo Antonio Chiquini-Medina
Keyword(s):  
Digital Camera ◽  
Tree Height ◽  
Reproductive Phenology ◽  
Ripe Fruit ◽  
Flower Buds ◽  
Phenological Stages ◽  
Diameter At Breast Height ◽  
Crown Diameter ◽  
Breast Height ◽  
Dependent Variables

Objective. To describe reproductive phenological stages, since the formation of flower buds, flowering, fruiting, up to the formation of the ripe fruit and foliation of 21 Couepia polyandra trees; and correlation of allometric data of tree height, diameter at breast height (DBH) and crown diameter, as well as the correlation of precipitation with reproductive phenology data. Methodology. The description of the reproductive phenology (foliage, formation of flower buds, flowers, fruits) was done by direct monthly observation with a digital camera (Canon SX60HS, 65). The correlation among precipitation, allometry, and types of soils where the trees grow was calculated by recording data from each tree by measuring height, diameter at breast height (DBH) and foliage. Results. The highest tree was 21.0 m; the widest DBH measured 68 cm; and the greater crown diameter was 34.45 m; the overall averages were 10.38 m, 33.17 cm and 9.37 m, respectively. A significant correlation was found between height and DBH (r=0.91, p<0.05); the correlations for the variables Height-Crown and DBH-Crown were not significant (p>0.05). Conclusions. Water as a factor is responsible for the formation of inflorescence and fruit; determining that these phenological events are dependent variables with precipitation, highlighting a mean positive relation with the growth of flowers.

scholarly journals Acacia melanoxylon in Argentina: heartwood content and its relationship with site, growth and age of the trees

2017 ◽  
Vol 26 (1) ◽  
pp. e007 ◽  
Author(s):  
Dora-Virginia Igartúa ◽  
Karen Moreno ◽  
Silvia-Estela Monteoliva
Keyword(s):  
Growth Rate ◽  
Linear Equations ◽  
Tree Height ◽  
Age And Growth ◽  
Absolute Amount ◽  
Basal Region ◽  
Total Height ◽  
Breast Height ◽  
Acacia Melanoxylon ◽  
Heartwood Diameter

Aims of study: To characterize the wood of Acacia melanoxylon in relation to its potential use in the construction and furniture industry, here we determined the heartwood and sapwood content and distribution within the stem and analyzed their relationship with the growing site, age and growth rate of the trees. Finally, we predicted heartwood content by two easy-to-measure variables.Area of study: Buenos Aires, Argentina.Methods: 20 trees aged between 9 and 32 years were sampled in four sites. Axial sampling was carried out at four heights of the stem (base, breast height, and 30% and 50% of the total height), and the heartwood content (percentage and volume) and sapwood content (cm) determined.Results: The trees analyzed presented conical-shaped heartwood following the outline of the stem along all its commercial height. Within the stem, the highest volume of heartwood was observed at the basal region (53%) and up to 30% of total height, a feature observed in all the sites studied. The sapwood content was constant along the entire stem (2.18 cm). The age of the trees did not influence the heartwood content, whereas the environmental conditions provided by each site (heartwood/volume and heartwood/diameter growth positive ratios) did affect this feature.Research highlights: The absolute amount of heartwood was driven by growth rate, due to the forest structure of non-uniform age. The heartwood volume can be estimated through fitting linear equations (R2 0.78 - 0.89) with two easily measurable variables such as diameter at breast height and tree height.

scholarly journals Contribution of some Savannah tree species in carbon sequestration

2021 ◽  
pp. 69-82
Keyword(s):  
Carbon Sequestration ◽  
Wood Density ◽  
Carbon Stock ◽  
Tree Height ◽  
Expansion Factor ◽  
Wood Volume ◽  
Biomass Expansion Factor ◽  
Diameter At Breast Height ◽  
Crown Diameter ◽  
Breast Height

Improvements in above ground biomass estimation can help account for changes in carbon stock in forest areas that may potentially participate in the clean development mechanism. The main objective of this study was to assess potential of some selected forest variables for modeling carbon sequestration for Combretum hartmannianum, Terminalia brownii, and Lanea fruitcosa. A total of 10 sample trees for Lanea fruitcosa and 8 sample trees for each of the other two species were selected for biomass and carbon determination were selected from El Nour Natural Forest Reserve of the Blue Nile State, Sudan. Data of diameter at breast height, total tree height, tree crown diameter, crown height, and upper stem diameters were measured. Then sample trees were felled and sectioned to their components and weighed. Subsamples were selected from each component for oven drying at 105 ˚C. Finally, allometric models were developed and the aboveground dry weight (dwt) and carbon sequestered per hector were calculated. The results presented biomass equations, biomass expansion factor and wood density that developed for the trees. In case of inventoried wood volume, corrections for biomass expansion factor and wood density value were done, and new values are suggested for use to convert wood volume to biomass estimates. The results also, indicate that diameter at breast height, crown diameter and tree height are good predictors for estimation of tree dwt and carbon stock. The developed allometric equations in this study gave better estimation of dwt than default value. The average carbon stock was found to be 22.57 t/ha.

scholarly journals Methods of Formation of Sustainable and Highly Productive Forest Plantations Created by Biogroups

2017 ◽  
Vol 7 (3) ◽  
pp. 58-65
Author(s):  
А. Вахтин ◽  
A. Vahtin ◽  
Владимир Вавин ◽  
Vladimir Vavin ◽  
Александр Ахтямов ◽  
...  
Keyword(s):  
Growth Rate ◽  
Tree Height ◽  
Forest Plantations ◽  
Crown Height ◽  
Trunk Diameter ◽  
Crown Diameter ◽  
Silvicultural Treatments ◽  
Group Methods ◽  
Significant Difference ◽  
Forest Belts

Protective forests created by nest and a diagonal-group methods in its development differ from ordinary forest stands created by planting of seedlings. In Stone Steppe from 1948 to 1954, 23.6 ha of the nesting forests were laid, and in the period 1955-1964 19 experimental and production diagonal and group belts with a total area of 27.8 ha was laid in the territory of the Institute and its experimental farms. Carrying out cleaning cuttings has a significant difference from silvicultural treatments in ordinary forest belts.The studies were conducted in forest belts, with test plots (TP) with the measurements of trees (trunk diameter, tree height, crown height, crown diameter in two directions). A comparative analysis was carried out according to the test plots on the areas with cleaning cuttings and without them. The results of research allowed to determine growth rate of tree species under the influenced of cleaning cuttings and it was used to develop methods of forest management treatments in forest belts, created by biogroups.Contemporary condition of experienced middle-aged forest belts was also studied with different methods of creation and allocation of seats on the silvicultural area.

The Research of Growth Model of the Pecan Tree Height, Trunk, Crown Diameter and DBH

2011 ◽  
Vol 250-253 ◽  
pp. 3858-3863
Author(s):  
Wen Bin Yao ◽  
Xiao Liang Li
Keyword(s):  
Growth Model ◽  
Tree Height ◽  
Regression Equation ◽  
Zhejiang Province ◽  
Diameter At Breast Height ◽  
Crown Diameter ◽  
Breast Height

500 pecans were measured in Henglu village of Linan city of Zhejiang province. Through measuring the tree height, trunk, crown diameter and DBH（diameter at breast height）and analyzing the correlation, the regression equation applicable to different range can be chosen.

Individual Tree Parameters Estimation from Terrestrial Laser Scanner Data

2017 ◽  
Author(s):  
Darius Popovas ◽  
Valentas Mikalauskas ◽  
Dominykas Šlikas ◽  
Simonas Valotka ◽  
Tautvydas Šorys
Keyword(s):  
Forest Management ◽  
Laser Scanner ◽  
Tree Height ◽  
Parameters Estimation ◽  
Carbon Accounting ◽  
Terrestrial Laser Scanner ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Crown Diameter ◽  
Breast Height

Tree models and information on the various characteristics of trees and forests are required for forest management, city models, carbon accounting and the management of assets. In order to get precise characteristics and information, tree modelling must be done at individual tree level as it represents the interaction process between trees. For sustainable forest management, more information is needed, however, the traditional methods of investigating forest parameters such as, tree height, diameter at breast height, crown diameter, stem curve and stem mapping or tree location are complex and labour-intensive. Light detection and ranging (LiDAR) has been proposed as a suitable technique for mapping of forest biomass. LiDAR can be operated in airborne configuration (Airborne laser scanning) or in a terrestrial setup. Terrestrial Laser Scanner measures forests from below canopy and offers a much more detailed description of the individual trees. The aim of this study is to derive the essential tree parameters for estimation of biomass from terrestrial LiDAR data. Tree height, diameter at breast height, crown diameter, stem curve and tree locations were extracted from Terrestrial Laser Scanner point clouds.

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.

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