Patterns in height-diameter relationships for selected tree species and sites in eastern Texas

1999 ◽  
Vol 29 (9) ◽  
pp. 1445-1448 ◽  
Author(s):  
Mark R Fulton

Relationships between tree height and diameter at breast height were described for 15 species across a range of sites in eastern Texas using a two-parameter equation. Maximum height varied significantly from site to site within a species, but the ratio of initial slope to maximum height was generally constant. Sites favoring tall trees of one species tended to favor tall trees of all species, especially among species found in the overstory. The greatest rates of height growth for a given diameter at breast height increment were found among some midstory and understory species.

2021 ◽  
pp. 106-125

The paper evaluated the performance of the current functional tree taper and volume models. The models were applied to some selected economically important natural Terminalia tree species common to central Sudan, namely, Terminalia laxiflora and, Terminalia brownii. 22 two-variable models (Diameter at breast height and total tree height or bole height) and 10 three-variables models (Diameter at ground level, Diameter at breast height and total tree height or bole height) were evaluated. The tree variables measured were the diameter at breast height (DBH, cm), diameter at the base of the tree (d0, cm), upper stem diameters (di), total tree height (H), and height to the base of the crown (Hb). Data were extracted from a natural reserved forest in the Blue Nile state. The models goodness of fit were evaluated in terms of adjusted coefficient of determination (Ra2), standard error (SE), mean absolute residual (MAR), bias (BI) Akaike’s information criterion (AIC), homogeneity of the residuals and significance of the regression parameters. Taper-17 and Taper-19 were found to be among the best two models for the two species with R2 range of 0.94 – 0.93, but with different rankings for each species. Comparison of the range of data for the tow studied species suggested that representation of various diameter at breast height (DBH, cm), diameter at the base of the tree (d0, cm), upper stem diameters (di), total tree height (H), and height to the base of the crown (Hb), had significant influence on the accuracy of prediction outside the range of the fitted data. This implies that application of the selected models is only useful at local stand level or at best in similar biological and stand structure conditions. For volume models, The results indicated that individual equations act differently in each species as there were great variations in the values of the same parameter of a given model accross the species. Some regression parameters of a given model were found to be significant in some species and insignificant in others. Comparison between the two versions of each group reveals that the replacement of the total tree height by the bole height (merchantable height) improves both the level of parameter significance and the coefficient of determination. From the first, the regression parameters of only 5 models (VOL-1, VOL-5, VOL-8, VOL-17, and VOL-20) were found to be significant at 0.05 probability level for all the tow species. The results also reveal that inclusion of variable D0 to the original two variables (DBH, Ht) to the volume equations results in insignificant improvement of the Ra2 values, while the replacement of the original model Ht variable with the Hb results in quite significant improvement of the Ra2 values. However, substantial improvement of the Ra2 values were obtained when both D0 and Hb were added. For this group of models, VOL-23, VOL-25- VOL-29 VOL30- and VOL-31were found to be the best for almost all the tow species. In general, the study concluded that taper and volume models can provide precise and accurate tree growth variables for the studied species with reasonable cost and time, but care should be taken when dealing with same model for the same species across the varying growth and management condition.


2021 ◽  
pp. 50-70

This paper developed and evaluated the performance of the current functional tree taper and volume models. The models were applied to some selected economically important natural tree species common to central Sudan, namely, Combretum hartmannianum and, Lonchocarpus Laxiflorus. The tree variables measured were the diameter at breast height (DBH, cm), diameter at the base of the tree (d0, cm), upper stem diameters (di), total tree height (H), and height to the base of the crown (Hb). In total, 19 taper and 32 volume models were tested and evaluated (22 models were two-variable models (Diameter at breast height and total tree height or bole height) and 10 were three-variable models (Diameter at ground level, Diameter at breast height and total tree height or bole height). The model goodness of fit was evaluated in terms of adjusted coefficient of determination (Ra2), standard error (SE), mean absolute residual (MAR), bias (BI) Akaike’s information criterion (AIC), homogeneity of the residuals and significance of the regression parameters. As far as taper models is concerned, Models, some of the models were found to yield satisfactory results for the tow selected species with R2 range of 0.94 – 0.96. For the within species variation of models on the basis of the AIC values, the ranking of the models (smaller AIC first) were in consistant with the rankings due to SE and Ra2 values although AIC penalizes models in proportion to the number regression parameters. In general the results of the study indicated that higher residuals valuse are in most of the cases associated with the lower parts of the bole, the butress portion of the stem. This suggests that care should be taken during the application of such models for hardwood species, especially in open woodlands where butress is a common characteristic.The results for volume models revealed differences in the behaviour of different models for each species as the degree of significance of the regression parameters varies between tree species. However, the replacement of the total tree height by the bole height (merchantable height) improves both the level of parameter significance and the coefficient of determination. The results also reveal that inclusion of diameter at grown level to the original two variables (DBH, Ht) and the replacement of the original model total height with the bale height results in quite significant improvement of the Ra2 values. In general, the study concluded that taper and volume models can provide precise and accurate estimation of tree growth variables for the studied species with reasonable cost and time, but care should be taken when dealing with same model for the same species across varying growth and management condition, or when dealing with different species. country.


2021 ◽  
Vol 13 (8) ◽  
pp. 4167
Author(s):  
David Kombi Kaviriri ◽  
Huan-Zhen Liu ◽  
Xi-Yang Zhao

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.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 380
Author(s):  
Karol Bronisz ◽  
Szymon Bijak ◽  
Rafał Wojtan ◽  
Robert Tomusiak ◽  
Agnieszka Bronisz ◽  
...  

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.


2015 ◽  
Vol 39 (6) ◽  
pp. 985-994 ◽  
Author(s):  
Markus Gastauer ◽  
Marcos Eduardo Guerra Sobral ◽  
João Augusto Alves Meira-Neto

According to its owners, the Forest of Seu Nico (FSN) from the Viçosa municipality, Minas Gerais, Brazil, never has been logged and is therefore considered a primary forest. Nevertheless, the forest patch suffered impacts due to selective wood and non-timber extraction, fragmentation and isolation. Aim of this study was to test if the FSN, despite impacts, preserved characteristics of primary forests, which are elevated percentages of non-pioneer (>90%), animal-dispersed (>80 %), understory (>50%) and endemic species (~40%). For that, all trees with diameter at breast height equal or major than 3.2 cm within a plot of 100 x 100 m were identified. With 218 tree species found within this hectare, the FSN's species richness is outstanding for the region. The percentages of non-pioneer (92 %), animal-dispersed (85 %), understory (55 %) and endemic species (39.2 %) from the FSN fulfill the criteria proposed for primary forest. Therefore, we conclude that the FSN maintained its characteristics as a primary forest which highlights its importance for the conservation of biotic resources in the region, where similar fragments are lacking or not described yet.


2010 ◽  
Vol 59 (1-6) ◽  
pp. 1-7 ◽  
Author(s):  
G. P. S. Dhillon ◽  
Avtar Singh ◽  
Pritpal Singh ◽  
D. S. Sidhu

Abstract Results from clonal trials of Populus deltoides conducted in two distinct agroclimatic regions of Punjab in northwestern India are reported and discussed. Sixteen clones were evaluated at Hambran and Bathinda where commonly grown clone ‘G-48’ was considered as control. Significant differences among clones (P < 0.001) were observed for diameter at breast height (DBH), tree height and volume at the age of four and six years under both the site conditions. Clone ‘L-48’ ranked first for volume at six year age at both sites and was followed by clone ‘Ranikhet’. The respective superiority for volume of these clones over control was 44.8 and 23.2 per cent at Hambran and 72.5 and 30.7 per cent at Bathinda. All growth traits registered significantly higher values at Hambran in comparison to those at Bathinda. Clone x site interaction was also significant (P < 0.001). The clones ‘L-168’, ‘154/86’, ‘Solan-z’ and ‘170/88’ experienced huge fluctuation in ranking between sites for volume at 6-year age. The DBH and height showed significant and positive correlation with each other and with tree volume at all the age combinations. The clonal mean heritability was quite high both at Hambran (0.73-0.86) and Bathinda (0.80-0.95). The genetic advance were the highest for volume (33.34-64.26%) and the lowest (10.65-22.79%) in case of height.


2012 ◽  
Vol 94 (4) ◽  
pp. 188-191 ◽  
Author(s):  
Megumi Ishida ◽  
Satoshi Naoi ◽  
Yasumasa Watanabe ◽  
Akinori Tsuzuku ◽  
Masaya Aoki

2016 ◽  
Vol 58 (1) ◽  
pp. 31-42 ◽  
Author(s):  
Katarzyna Kaźmierczak ◽  
Bogna Zawieja

AbstractThe paper presents an attempt to apply measurable traits of a tree – crown projection area, crown length, diameter at breast height and tree height for classification of 135-year-old oak (QuercusL.) trees into Kraft classes. Statistical multivariate analysis was applied to reach the aim. Empirical material was collected on sample plot area of 0.75 ha, located in 135-year-old oak stand. Analysis of dimensional traits of oaks from 135-year-old stand allows quite certain classification of trees into three groups: pre-dominant, dominant and co-dominant and dominated ones. This seems to be quite promising, providing a tool for the approximation of the biosocial position of tree with no need for assessment in forest. Applied analyses do not allow distinguishing trees belonging to II and III Kraft classes. Unless the eye-estimation-based classification is completed, principal component analysis (PCA) method provided simple, provisional solution for grouping trees from 135-year-old stand into three over-mentioned groups. Discriminant analysis gives more precise results compared with PCA. In the analysed stand, the most important traits for the evaluation of biosocial position were diameter at breast height, crown projection area and height.


2016 ◽  
Vol 32 (6) ◽  
pp. 498-509 ◽  
Author(s):  
Carlos L. O. Cordeiro ◽  
Dilce F. Rossetti ◽  
Rogério Gribel ◽  
Hanna Tuomisto ◽  
Hiran Zani ◽  
...  

Abstract:Amazonian white-sand vegetation has unique tree communities tolerant to nutrient-poor soils of interest for interpreting processes of adaptation in neotropical forests. Part of this phytophysionomy is confined to Late Quaternary megafan palaeo-landforms, thus we posit that sedimentary disturbance is the main ecological factor controlling tree distribution and structuring in this environment. In this study, we characterize the topographic trend of one megafan palaeo-landform using a digital elevation model and verify its relationship to the forest by modelling the canopy height with remote sensing data. We also compare the composition and structure (i.e. canopy height and diameter at breast height) of tree groups from the outer and inner megafan environments based on the integration of remote sensing and floristic data. The latter consist of field inventories of trees ≥ 10 cm dbh using six (500 × 20 m) plots in várzea, terra firme and igapó from the outer megafan and 20 (50 × 20 m) plots in woodlands and forests from the inner megafan. The unweighted pair group method with arithmetic mean (UPGMA) and the non-metric multidimensional scaling (NMDS) were applied for clustering and dissimilarity analyses, respectively. The megafan is a sand-dominated triangular wetland with a topographic gradient of < 15 cm km−1, being more elevated along its axis. The outer megafan has a higher number of tree species (367), taller canopy height (mean of 14.1 m) and higher diameter at breast height (mean of 18.2 cm) than the white-sand forest. The latter records 89 tree species, mean canopy height of 8.4 cm and mean diameter at breast height of 15.3 cm. Trees increase in frequency closer to channels and toward the megafan's axis. The flooded and nutrient-poor sandy megafan substrate favoured the establishment of white-sand vegetation according to the overall megafan topography and morphological heterogeneities inherent to megafan sub-environments.


Sign in / Sign up

Export Citation Format

Share Document